From 285bd723d169a593027380d137ded098866e7dfa Mon Sep 17 00:00:00 2001
From: softwarehsc <2316414389@qq.com>
Date: Sun, 16 Sep 2018 17:27:02 +0800
Subject: [PATCH] Last one

---
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 rename 031602408/{wordCount => }/.classpath (100%)
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 create mode 100644 031602408/bin/Main.class
 create mode 100644 031602408/bin/input.txt
 create mode 100644 031602408/bin/lib/Store$1.class
 rename 031602408/{wordCount/bin/lib/java => bin/lib}/Store.class (62%)
 create mode 100644 031602408/src/Main.class
 rename 031602408/{wordCount/src/main/java/WordCount.java => src/Main.java} (80%)
 create mode 100644 031602408/src/input.txt
 create mode 100644 031602408/src/lib/Store$1.class
 create mode 100644 031602408/src/lib/Store.class
 rename 031602408/{wordCount/src/lib/java => src/lib}/Store.java (90%)
 create mode 100644 031602408/src/result.txt
 delete mode 100644 031602408/wordCount/bin/input.txt
 delete mode 100644 031602408/wordCount/bin/lib/java/Store$1.class
 delete mode 100644 031602408/wordCount/bin/main/java/WordCount.class
 delete mode 100644 031602408/wordCount/src/input.txt
 delete mode 100644 031602408/wordCount/src/main/java/wordCount.txt
 delete mode 100644 031602408/wordCount/src/result.txt

diff --git a/031602408/wordCount/.classpath b/031602408/.classpath
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rename from 031602408/wordCount/.classpath
rename to 031602408/.classpath
diff --git a/031602408/wordCount/.project b/031602408/.project
similarity index 93%
rename from 031602408/wordCount/.project
rename to 031602408/.project
index 718cf4a..197a790 100644
--- a/031602408/wordCount/.project
+++ b/031602408/.project
@@ -1,6 +1,6 @@
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diff --git a/031602408/wordCount/.settings/org.eclipse.jdt.core.prefs b/031602408/.settings/org.eclipse.jdt.core.prefs
similarity index 100%
rename from 031602408/wordCount/.settings/org.eclipse.jdt.core.prefs
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diff --git a/031602408/bin/input.txt b/031602408/bin/input.txt
new file mode 100644
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+Cystic fibrosis affects 30,000 children and young adults in the US alone
+Inhaling the mists of salt water can reduce the pus and infection that fills the airways of cystic fibrosis sufferers, although side effects include a nasty coughing fit and a harsh taste. 
+That's the conclusion of two studies published in this week's issue of The New England Journal of Medicine.
+They found that inhaling a mist with a salt content of 7 or 9% improved lung function and, in some cases, produced less absenteeism from school or work. 
+Cystic fibrosis, a progressive and frequently fatal genetic disease that affects about 30,000 young adults and children in the US alone, is marked by a thickening of the mucus which makes it harder to clear the lungs of debris and bacteria. 
+The salt water solution "really opens up a new avenue for approaching patients with cystic fibrosis and how to treat them," says Dr Gail Weinmann, of the US National Heart, Lung, and Blood Institute, which sponsored one of the studies. 
+Mark Elkins of the Royal Prince Alfred Hospital in Sydney, Australia and colleagues authored one of the new published studies.
+The team found that the 83 volunteers who regularly inhaled a 7% mist of salty water had fewer breathing problems and less absenteeism from school or work than those who inhaled a solution with a salt content of under 1%. 
+"Adding salt [and water] to the airway surfaces of patients with cystic fibrosis is beneficial" for both children and adults, they conclude. 
+All of the patients first inhaled a chemical to try to open their lung passages as much as possible.
+In the second study, US-based Assistant Profsesor Scott Donaldson of the University of North Carolina at Chapel Hill and his colleagues found that a 7% salt mist "produced a sustained acceleration of mucus clearance and improved lung function" because it helped hydrate the lungs.
+In an accompanying editorial, Dr Felix Ratjen of the Hospital for Sick Children in Toronto, Canada, cited several unpleasant side effects of the salt mist treatment including a bad taste, coughing fits and the lengthy 30 minutes it can take to administer. 
+He added that in the study by Elkins and team, patients may not have received the best long-term antibiotic treatment. 
+That would make the inhaled salt water mist appear more effective than it would have been if people were getting a better drug, says Ratjen. 
+Weinmann says limitations inherent to the treatment mean a salt water mist "may be just a first step" in treating cystic fibrosis.
+
+Scientists have rescued a mouse immune system that was overwhelmed by a systemic blood infection. But will this work in humans?
+Scientists have discovered how infections that invade the whole body, like malaria, disable the immune system and prevent it from detecting and fighting other microorganisms.
+The Australian and German researchers say the discovery may help scientists to develop vaccines that restore immunity in people with systemic or 'whole body' infections. 
+They publish their research today online in the journal Nature Immunology.
+The immune response is alerted when specialised sentries of the immune system, dendritic cells, detect a virus or bacteria.
+They alert the immune system by capturing infected cells and displaying fragments or antigens of the pathogen on their surface in a process called cross-presentation.  
+Lead researcher Dr Jose Villadangos, an immunologist from the Walter and Eliza Institute of Medical Research in Melbourne, says systemic infections such as malaria or sepsis, a bacterial infection of the blood, overstimulate dendritic cells.
+This results in the immune system's critical alarm system shutting down.
+"This doesn't occur in local infections because only a few dendritic cells are involved," Villadangos says.
+"But in the case of malaria infections and sepsis, dendritic cells throughout the body are concentrated on alerting the immune system, which prevents them from detecting and responding to any new infections." 
+A new type of vaccine?
+Villadangos and colleagues managed to restore immunity in mice with an immune system compromised by sepsis.
+They injected them with a live vaccine made of dendritic cells that had been exposed to a secondary virus in the laboratory, and subsequently displayed antigens of that virus. 
+Villadangos says the findings show the missing link in the immunosupressed animal is the capacity of the dendritic cells to display the antigens of new viruses. 
+"We should be able to take dendritic cells from a patient with sepsis or malaria and expose them to antigens of the virus of a secondary infection and inject them back into the patient.
+"This strategy is already being used in the development of anti-cancer vaccines. We are yet to find out if will work against secondary infections in humans with a systemic infection," Villadangos says.
+
+Scientists will analyse the contents of this capsule for clues about how the solar system began
+A seven-year quest to return to Earth pristine samples from the solar system's formation ended in triumph in a dark and wet Utah desert at the weekend. 
+"It's hard to describe what it feels like to be at this point of the mission," University of Washington researcher and lead scientist of the Stardust mission Professor Don Brownlee said shortly after the probe's touchdown at 10:10 UTC (21:10 AEDT) on Sunday. 
+"We travelled almost 3 billion miles in space. We visited a comet, grabbed a piece of it and it landed here this morning," Brownlee said. "It's an incredible thrill." 
+Stardust released its precious cargo during a high-speed flyby of Earth, sending the tyre-sized canister soaring through space at a blazing speed of about 46,000 kilometres per hour when it smashed into the planet's atmosphere.
+This makes it the fastest human-made object, topping the record set in May 1969 by the returning Apollo 10 command module. 
+As its heat-shield fried away, a comet-like plume formed in its wake, looking like a torch that was visible in parts of the western US. 
+"We weren't quite sure how bright it was going to be and some people didn't think we would see anything," says Brownlee, who slipped outside the Utah base with some of his team members to try to spot the capsule's streak across the sky. 
+After scanning the sky for several minutes, Brownlee finally found an object that he said looked like Mars, but was clearly not where Mars was at the time. 
+"It was twinkling a little bit, getting a little brighter, and moving. I thought, maybe that's a helicopter. But it kept getting brighter and brighter and brighter," he says. 
+The object was reddish in colour and trailed a bright, glowing plume behind it, Brownlee says.
+"It's ironic, you have a comet mission that ends producing a comet." 
+Collecting spacedust
+During its time in space, Stardust passed by Comet Wild-2 (Vilt-2) and extended a gel-filled collecting device to trap some particles to take back to Earth. It also collected bits of interstellar dust. 
+Scientists believe comets contain unaltered material that was used to form the solar system. 
+"We did this mission to collect the most primitive materials we could in the solar system," Brownlee says.
+"We went to a comet that formed at the edge of the solar system, far from the Sun under very cold conditions. We're confident that it was made out of the initial building blocks of our solar system." 
+The capsule was retrieved by helicopter crews and taken to a clean room on the Utah Test and Training Range for inspection.
+The canister containing the samples is scheduled to be removed from the capsule and flown to the NASA Space Center in Houston on Tuesday. 
+There, scientists will catalogue the samples and begin distributing them to teams for analysis.
+
+Gotcha! A colourful, striking image can spark your interest
+Internet users can take just one-twentieth of a second to decide whether they like the look of a website, new research has found.
+"Visual appeal can be assessed within 50 milliseconds, suggesting that web designers have about 50 milliseconds to make a good impression," the Canadian researchers report in the March/April issue of the journal Behaviour & Information Technology.
+Dr Gitte Lindgaard and colleagues from Carleton University in Ottawa confirm that internet users are a fickle lot.
+The team did this by flashing up websites for 50 milliseconds and asking participants to rate them for visual appeal.
+When they repeated the exercise after a longer viewing period the ratings were consistent.
+The medium is the message
+The finding comes as bad news to anyone hoping to convey information, says Sue Burgess, an Australian researcher who evaluates website useability and senior lecturer in information management at the University of Technology Sydney.
+"There's no doubt that people do respond very quickly to websites and decide very quickly whether to stay on them," she says.
+The appeal of a website is usually tied to colour, movement and interactivity, she says, with the way the information is structured coming second.
+Burgess says it's unclear whether the internet is changing our ability to concentrate for long periods our if we are adapting to the medium.
+"There's so much information and ... there's always going to be a lot of clicking around just to see what's there," she says.
+The halo effect
+Australian associate professor of psychology Bill von Hippel, from the University of New South Wales, says it takes about 50 milliseconds to read one word, making this a "stunningly remarkable" timeframe in which to process the complex stimuli on a website.
+"It's quite remarkable that people do it that fast and that it holds up in their later judgement," he says.
+"This may be because we have an affective or emotional system that [works] independently of our cognitive system."
+In evolutionary terms, this ability helped us respond rapidly to dangerous situations, he says.
+The study also reflects the so-called halo effect, von Hippel says, where an initial bias towards something drives subsequent judgements.
+"This suggests that we make very quick judgements based on some sort of emotional reaction and our more considered judgements still reflect that first impression."
+
+Jewish people's history and migrations are reflected in their DNA, a new study shows
+Four Jewish mothers who lived 1000 years ago in Europe are the ancestors of 40% of all Ashkenazi Jews alive today, international researchers report.
+The DNA study paints a vivid picture of human evolution and survival, and correlates with the well-established written and oral histories of Jewish migrations, says Dr Doron Behar of the Technion-Israel Institute of Technology, who worked on the study. 
+The study, published in the American Journal of Human Genetics, suggests that some 3.5 million Jews alive today descended from four women. 
+For their study, Behar and scientists from Europe and the US sampled DNA from 11,452 people from 67 populations.
+"All subjects reported the birthplace of their mothers, grandmothers, and, in most cases, great-grandmothers," the scientists write. 
+They looked at mitochondrial DNA, which is found in cells, outside the nucleus and away from the DNA that carries most genetic instructions.
+Mitochondrial DNA is passed down virtually unchanged from mother to daughter, but it does occasionally mutate, at a known rate. 
+Researchers can use this molecular clock to track genetic changes through time.
+They used it, for instance, to compute when the "ancestral Eve" of all living humans lived: in Africa, about 180,000 years ago. 
+Now they have found four ancestral Jewish mothers. 
+"I think there was some kind of genetic pool that was in the Near East," Behar says.
+"Among this genetic pool there were four maternal lineages, four real women, that carried the exact specific mitochondrial DNA markers that we can find in mitochondrial DNA today." 
+Settling Europe
+They, or their direct descendants, moved into Europe. 
+"Then at a certain period, most probably in the 13th century, simply by demographic matters, they started to expand dramatically," Behar says. 
+"Maybe it was because of Jewish tradition, the structure of the family that might have been characterised by a high number of children."
+But these four families gave rise to much of the population of European Jews, which exploded from 30,000 people in the 13th century to "something like 9 million just prior to World War II", Behar says.
+The Nazis and their allies killed 6 million Jews during the war, but there are now an estimated 8 million Ashkenazi Jews, defined by their common northern and central European ancestry, cultural traditions and Yiddish language. 
+Behar says as they sampled people from Ashkenazi communities around the world, the same mitochondrial genetic markers kept popping up.
+They did not find the markers in most of the non-Jewish people they sampled, and only a very few were shared with Jews of other origin.
+Ancestry not genetic disease
+This particular study does not provide a direct explanation for some of the inherited diseases that disproportionately affect Jews of European descent, such as breast and colon cancer, because most diseases are caused by mutations in nuclear DNA, not the DNA studied by Behar's group. 
+These genes are believed to date from a 'bottleneck' phenomenon, when populations were squeezed down from large to small and then expanded again.
+Behar and Skorecki's team have found what is known as a 'founder effect', when one or a small number of people have a huge number of descendants.
+
+Scientists hope to gain an insight into the secret life of clouds with Australia's biggest climate experiment
+International storm chasers gathering in Australia this week will release more than 1000 weather balloons over the next month as part of the nation's largest meteorological study.
+The Tropical Warm Pool International Cloud Experiment, based in Darwin, will provide the world's most comprehensive set of data about the behaviour of thunderclouds, says Dr Peter May, a principal research scientist at the Australian Bureau of Meteorology in Melbourne.
+May says the study will give scientists better ways of modelling cloud behaviour, resulting in more accurate short-term weather forecasting and better predictions for long-term climate change.
+"The biggest uncertainty in climate forecasts and greenhouse calculations comes down to our understanding of thunderstorms," he says.
+"The underlying aim of this experiment is to increase our understanding of thunderstorms themselves, how they evolve and the large scale impact they have."
+Collaborators in the project include the bureau, the US Department of Energy Atmospheric Radiation Measurement Program, the CSIRO, NASA and universities from Australia, the US, Europe, Canada and Japan.
+Measuring ice crystals
+May says the tropical weather conditions in Darwin, which was devastated by Cyclone Tracy in 1974, provide a natural laboratory for storm watchers.
+And this is the time of year for tropical storms, when Darwin has its monsoon-like 'wet' season.
+The multi-million dollar study will have three prongs. 
+May says research planes will fly directly into the clouds to measure ice crystals while a ground-based network will use radars, laser and infrared systems to look at cloud characteristics and the movement of heat, moisture and light.
+And weather balloons will be released every three hours over 23 days from five sites around Darwin.
+"This data set is going to be a real resource for the whole meteorological community," May says.
+"It'll be the data set that people go to develop new model systems for the next 20 years. There will be dozens, if not hundreds of papers written about this experiment."
+May says the link between climate change and global storm patterns is unclear.
+But he says it's unlikely that climate change is directly responsible for isolated events, like Hurricane Katrina that struck New Orleans last year.
+"The question isn't is a particular storm due to climate change, the question is are we loading the dice so that we can expect more storms or will they be more intense," he says.
+
+Artists think Pluto looks like this. But we won't know for certain until NASA's New Horizons spacecraft, due to launch this week, reaches the distant planet in about a decade
+The US space agency is set to shed light on Pluto with the launch of the New Horizons spacecraft this week.
+The spacecraft, which is due to be launched at 05:24 AEDT on Wednesday (18:24 UTC, Tuesday) will also investigate a new class of planet-like objects, called ice dwarfs, that exist beyond the orbit of Neptune.
+Over the decades, NASA has launched probe after probe for close-up studies of Earth's sister planets. But distant Pluto has remained shrouded in mystery, with only a few fuzzy telescope pictures for scientists to ponder. 
+"What we know about Pluto today could fit on the back of postage stamp," says Dr Colleen Hartman, NASA's deputy associate administrator for science.
+And New Horizon's principal investigator Dr Alan Stern, with the Southwest Research Institute in Boulder, Colorado, agrees we have much to learn about the history of these distant objects.
+"These are objects that were growing to planethood, but something stopped that process of growth mid-gestation," he says. "It left us these fossil relics." 
+Pluto is the largest and best-known object in the Kuiper Belt region of the solar system.
+Like comets, the planetary bodies in the Kuiper Belt region are so far from the Sun that scientists believe they still contain some of the original material that was used to form the solar system. 
+How the universe formed
+New Horizons is a U$700 million (A$928 million) attempt to learn more about how the universe formed.
+The piano-sized spacecraft contains seven science instruments to map Pluto, its largest moon Charon, and two other recently discovered smaller moons, as well as other Kuiper Belt objects. 
+To shave as much time as possible from the journey to Pluto, which will take more than nine years, NASA is launching New Horizons aboard a massive rocket typically used for communications satellites five to 10 times heftier than the half-tonne science probe. 
+The launch vehicle, an Atlas 5 rocket with two upper-stage motors and an unprecedented five solid-rocket strap-on boosters for extra punch, has successfully flown six previous missions.
+The rocket was rolled out from its hangar to its Cape Canaveral launch pad earlier this week.
+Even with the 58,000 kilometre per hour boost into space, New Horizons will still need to bounce off Jupiter's massive gravity field and travel for nearly a decade to reach Pluto. 
+Hitching a ride
+If the probe cannot be launched by 2 Feburary it will miss the opportunity to slingshot off Jupiter and take an additional three to five years to reach Pluto, depending on the actual launch date. 
+Scientists, who already have waited decades for NASA to approve and fund a mission to Pluto, are happy to at last be on their way. 
+"This is a place where nature operates at vastly different temperatures and conditions than we're familiar with on Earth," says New Horizons co-investigator Professor Richard Binzel with the Massachusetts Institute of Technology. 
+"We're poised to begin the exploration of a new world," adds Dr Dale Cruikshank, with the NASA Ames Research Center in California.
+
+Backpackers form a highly mobile community, says a researcher who's developing a new communication device especially for them
+Backpackers may one day use a mobile travel assistant to ring home and network with other travellers while finding out the cost of a bus ticket to Bondi Beach, an Australian researcher says.
+The digital travel buddy would also act as a travel guide with information about the best places to go and how to get there, says Jeff Axup, a PhD student at the University of Queensland and former backpacker.
+Axup has been studying backpacker culture and communication as part of his research into the technology needs of so-called mobile communities.
+"A lot of research focuses too much on the technology and tries to find an application," he says.
+"We like to look at how people naturally act and try to come up with technology to fit their needs."
+In a recent study Axup shadowed a group of backpackers and documented their behaviour as they toured Brisbane, took a boat cruise and visited an animal park.
+The results of his study are published on the ePrintsUQ website and will be submitted for publication in coming weeks.
+Axup's latest research includes prototypes of the technology, which is being developed with the Australasian CRC for Interaction Design.
+The final product will probably be software-based so backpackers can download it onto their mobile phones, he says.
+And it will be likely to include instant messaging and discussion forums, or use wireless technology.
+Mobile communities
+Axup says backpackers are cultural symbols of an increasingly mobile world, a change brought about by improved transport and technology and the breakdown of the traditional neighbourhood.
+"One term to describe this is glocalisation, where you still have your local communities but they've gone global and they may be distributed," he says.
+Backpackers already use mobile phones, text messaging and the internet but Axup's research shows that they are driving changes in technology as much as the technology is changing the nature of travel.
+"Any time you introduce new technology it always enters an existing social and technological environment, so it will of course change the existing environment," he says.
+"But then people will take it and use it in ways that were never expected and maybe even change the technology."
+
+Watching a comedy is as good for the heart as aerobic exercise, new research suggests
+Watching a comedy film boosts the flow of blood to the heart, but watching a sad film makes the flow decline, a US study shows.
+University of Maryland researchers asked 20 young people to watch movie segments lasting 15 to 30 minutes, taken from comedy films and serious films, with at least 48 hours between the two sessions. 
+With the help of ultrasound, the researchers measured the study participants' blood flow through the brachial artery.
+This vessel runs between the shoulder to the elbow and its blood flow is thought to be a good indicator of blood flow around the body.
+Blood flow was reduced in 14 of the 20 volunteers when they watched extracts such as the distressful opening scenes to Saving Private Ryan.
+But blood flow rose in 19 out of 20 when they watched funny clips, such as scenes from Something About Mary. 
+The difference between the two flows was more than 50%, according to the study, which appears today in the journal Heart. 
+Watching a sad movie has about the same effect on heart flow as remembering an angry incident or doing mental arithmetic, it says. 
+But watching a comedy is equivalent to a bout of aerobic exercise or starting a course of cholesterol-busting statin drugs. 
+Depression, anxiety, hostility and anger are already known to impair nitric oxide pathways that help blood vessels to dilate. 
+The authors tentatively suggest that a chuckle may stimulate selected hormones to have the opposite effect. 
+"Positive emotions such as mirthful laughter [may] have a [beneficial] effect on the endothelium," the cells that line the walls of the blood circulation system, they speculate.
+
+Why did the turtle cross the road? Because it wanted lunch
+Scientists are studying the wandering ways of Australia's eastern long-necked turtle to see if can learn to cross the road.
+Professor Arthur Georges, director of the applied ecology research group at the University of Canberra, says it's the first time researchers have documented how roads affect the turtles.
+Georges says unlike other turtles, Chelodina longicollis has evolved the ability to take long overland hikes because it prefers ephemeral waters, such as temporary swamps and pools.
+"When a wetland dries, the nutrients are released from the sediment and when it refills there's a flush of production, so they're capitalising on all the insects and other foods that benefit from that flush," he says.
+The hardy creatures gravitate to permanent waters in a drought, where they can  'switch off' growth and reproduction, sometimes for as long as seven years. They then hit the road as soon as the rains come.
+Georges and his team are studying a population of turtles in Jervis Bay in southern New South Wales and hope to have some results ready for publication in the middle of the year.
+Look right, look left, look right again
+Georges says the long-necked turtle is familiar with its environment and may even have learnt to avoid roads.
+"What we have found is that they ... use the Sun and an internal clock to navigate and they know landscape really well so they tend to beeline to various places," he says.
+"We're going to take them from the wetlands and release them near a road and observe their behaviour as they approach the road. They may have an aversion to [it] and turn around."
+But if the road safety message hasn't sunk in it may be necessary to build tunnels under roads to provide them with safe passage, he says.
+While it appears that some aspects of development have got in the way of the turtle's natural behaviour, it hasn't been all bad for the long-necked turtle, Georges says.
+"When you fly over [surrounding farmland] you'll see there are lots of dams," he says.
+"Each one is full of about 20-30 turtles, and those sorts of water bodies weren't there before," he says.
+"But on the downside, when a road runs through a wetland you can increase the chance that over time the population will decline."
+
+Landslides like this one in Pakistan earlier this week may become more common if climate change increases rainfall, scientists say
+Heavier rainfall as a result of climate change could loosen soils making landslides more common, UN experts say.
+This may risk hillside slums in Latin America to antiquities in Egypt's Valley of the Kings, according to scientists meeting in Tokyo this week to discuss ways to prevent and ease damage from landslides.
+"If climate change predictions are accurate you will expect ... more intense and extreme rainfalls," says Professor Srikantha Herath, senior academic officer of the UN University. 
+A report released at the time of the meeting says some cultural sites are at risk from landslides, including the Valley of the Kings where Egypt's Pharaohs are buried, the Inca mountain fortress of Machu Picchu in Peru and China's Huaqing Palace dating from the Tang dynasty. 
+"Special attention should be given to cultural and natural heritage sites of universal and irreplaceable values," says Professor Kyoji Sassa, director of the Disaster Prevention Research Institute at Japan's Kyoto University.
+"In some places, particularly in developing countries, the natural threats are being exacerbated by rapid tourism development," he says.  
+Early warning
+Herath says the Tokyo talks are likely to call for better monitoring and early warning systems, special protection of cultural sites, better preparedness and quick aid for victims. 
+He says it is impossible to say if global warming is already causing more landslides. 
+Of natural disasters, landslides are the seventh biggest killer behind droughts, storms, floods, earthquakes, volcanoes and extreme temperatures, according to the report for the UN University, Kyoto University and UNESCO.
+Among severe landslides, about 2800 died in Cholima in Honduras in 1973 and almost 1200 in northern Italy in 1963.
+The Louvain University database on which the figures are based often excludes landslides triggered by earthquakes. 
+Unstable hillsides
+In many poor nations, many people were forced to live on unstable hillsides, away from flat plains exploited for farming. 
+"Late arrivals are always settling in the most dangerous land," says Professor Janos Bogardi, director of the UN University Institute for Environment and Human Security. 
+He says that better building codes and simply giving out information about the risks of mudslides could save lives.
+Asia suffered most with 220 landslides in the past century out of about 500 that caused human deaths, the scientists say. Many of the most deadly mudslides were in Latin America and the costliest in Europe. 
+About 800-1000 people died in landslides in each of the past 20 years, the UN University says.
+
+The wind may carry legionnaires bacteria from cooling towers much further than once thought, scientists say
+The bacteria responsible for causing legionnaires disease can spread through the air up to 6 kilometres from its source, French researchers report. 
+Legionella pneumophila likes to live in hot water, such as in industrial cooling towers or the water systems of large buildings where it can then cause pneumonia-like infections.
+Now a new study suggests that a wider area may be at risk. 
+Past studies found airborne legionella spread only a few hundred metres, says lead author Dr Tran Minh Nhu Nguyen, currently at the National Public Health Institute in Helsinki.
+If other investigators confirm the new findings, he says "a number of regulations and guidelines related to this environmental health risk should be revised accordingly".
+In the Journal of Infectious Diseases, Nguyen and his team report on their investigation of a 2004 outbreak of legionnaires disease that occurred in Pas-de-Calais in northern France. 
+They identify a contaminated cooling tower at a petrochemical plant as the source of the outbreak, which killed 21 of the 86 people with laboratory-confirmed infection.
+Most of the victims lived within 6 kilometres of the plant, although one lived 12 kilometres away. 
+The fatality rate is "striking" when compared with past community-acquired outbreaks, in which fatality rates were 1 to 11%, the researchers note.
+They think the strain of legionella involved could have been unusually virulent. 
+The outbreak occurred in two peaks, the first ending after the cooling tower had been shut down and the second beginning during cleaning of the tower and peaking once it had reopened. 
+The pattern suggests that high-pressure cleaning methods used to decontaminate the towers contributed to the bacteria's spread.
+"There are measures and guidelines for managing cooling towers contaminated with legionella," Nguyen says. "However, how well they have been adopted and implemented depends on the individual country and setting."
+
+Map collector Liu Gang speaks in Beijing in front of a slide of a map which is said to be an 18th century copy of the 1418 original and showing the Americas in unusual detail
+A Chinese map collector has found a copy of an ancient map he claims proves controversial theories that a famed Chinese mariner was the first to sail to the Americas and circumnavigate the world. 
+Liu Gang says the map supports recent theories that Chinese people sailed to America before Christopher Columbus and charted parts of the world such as Antartica and northern Canada long before Western explorers. 
+"The map shows us that Chinese discovered the world 70 years before Columbus," Liu said in a public unveiling of the chart. "The map tells us that [mariner] Zheng He discovered the world."
+The map is dated to 1763 but is also clearly marked that it is a copy of a map made in 1418. That date coincides with Zheng He's voyages, from 1405 to 1432. 
+Liu bought the map for about US$500 (A$666) from a map collector in Shanghai in 2001, but only realised its importance after he read Gavin Menzies' best-selling book 1421: The Year China Discovered The World. 
+In the book Menzies theorises that previously undiscovered world maps drawn up by Zheng He's admirals were copied by European map makers and were extensively used during the voyages of great Western explorers, including Columbus, Ferdinand Magellan, Vasco Da Gama and James Cook. 
+Much of Menzies' theories are supported by his knowledge of ocean currents, continental trade winds and star navigation that he learned during his life as a British naval commander. 
+Despite its prominence on best-seller lists, many historians have criticised Menzies' theories for the lack of accompanying evidence. 
+China's Ming Dynasty banned ocean-going exploration and trade on pain of death after Zheng He's final voyage, largely due to the death of Emperor Zhu Di, who sponsored the voyages. 
+The huge costs of Zheng's fleets, which often numbered hundreds of ships, were another factor. 
+The Chinese records of Zheng He's voyages have largely been lost, either purposely destroyed as part of the ban on ocean-going navigation or due to a fire that ravaged Beijing's imperial palace in the 1420s. 
+Liu believes a lot of the records still exist, but Chinese scholars have largely ignored them. 
+"I sincerely believe that other maps exist and books exist [that contain evidence of Zheng He's world travels] but no-one has been paying attention to them," Liu says. "It is my purpose to try to wake these [scholars] up."
+
+The new fridge magnets will be aware of others on the fridge and communicate with them
+Fridge magnets may one day be able to fix bad grammar and change the words to something they think is more appropriate.
+"The idea is that each magnet is aware of the other magnets on the fridge and they transmit information between each other," says Australian digital artist Pierre Proske.
+Proske is working with researchers at the Future Applications Lab of the Viktoria Institute in Sweden to develop the intelligent fridge magnets.
+Details will be presented at the  International Conference on Intelligent User Interfaces in Sydney later this month.
+Each fridge magnet consists of 16-character liquid crystal display, rather than a magnetic strip with a printed word, Proske says.
+The magnets can randomly generate a word, categorise that word (as a noun, verb, adjective or adverb) and transmit the category to any words they are placed next to.
+As you compose a poem, placing words in grammatical order, the magnets communicate with each other to learn the grammar rules you are using.
+Once they are 'trained', the magnets can change the words they are displaying to substitute words that don't fit the established grammar rules, like an autocorrect function.
+"So the actual word that's associated with each magnet can change depending on the way in which it's aligned," says Proske.
+Reshuffling gives you a new word
+Luckily if you don't like the word the magnet substitutes, you can always take the magnet off the fridge and shake it to reshuffle and get a new word.
+And the plan is for you to be able to reset the magnets completely so they forget all their grammar rules.
+Of course, the magnets rely on being taught good grammar in the first place.
+"Someone could instil bad grammar if they wanted to," says Proske.
+But he doesn't want to take all the fun for those kitchen-based party-goers that like making up crazy sentences on fridges.
+He says the system will only worry about which words can be immediately next to each other and won't be too strict about the grammar of the sentence as a whole.
+"This was deliberate to keep the sentences a little more poetic," says Proske.
+"The idea is it is still fridge poetry. We don't want to create sentences that make total sense." 
+Changing words to fit themes
+The team also hopes that the magnets will be able to substitute words in response to stimuli other than bad grammar.
+For example, someone might have a set of magnets on the home fridge and a set of magnets on the work fridge that can communicate via wireless internet, says Proske.
+If the magnets at home read, for example, "Crazy kangaroos dream wildly", those at work might change to "Drunk wallabies laze around the pool", in keeping with the Australian theme.
+The team also suggest it might be interesting to apply their ideas to Scrabble and crosswords but says further details on this are a subject for further investigation.
+Proske and colleagues have so far half developed a prototype intelligent fridge poetry magnet system and are hoping to get more ideas at the Sydney conference.
+And they're not just interested in generating another product for the consumer market.
+This is a "whimsical and accessible" way to contribute to the study of developing intelligent robots, says Proske.
+
+The findings could explain the traditional job of men as society's enforcers, say researchers
+Men are likely to take pleasure when they see someone punished for acting unfairly, while women are likely to feel badly for the culprit, say neuroscientists.
+Dr Tania Singer of University College London and team report their findings today online ahead of print publication in the journal Nature.
+In a two-phase experiment, the researchers recruited 32 male and female volunteers, as well as four others who were undercover actors hired to play the role of volunteers. 
+In the first part of the experiment, the group played a game of mutual investment in which they had to give money to one of their number.
+The recipient decided how much to give back from the profits. They could hand back up to triple the investment, at little reward to themselves, or hand back little or nothing, maximising their own gains at the investor's cost.
+One actor was cast in a generous role, always giving lots of money back to their partners, while another actor was cast as a meanie, giving back very little and sometimes nothing at all.
+Body language by the volunteers, confirmed later in questionnaires, confirmed that they did not like the actors who had cheated on them.
+"Fair" players, in contrast, were rated as more agreeable, more likeable and, remarkably, more attractive.
+Brain imaging reveals sex differences
+In the second phase, the same volunteers were each placed in a magnetic resonance imaging scanner, a device which shows blood flows within the brain. 
+The volunteer was then given a demonstration of a mild shock, the equivalent of short bee-sting, and then watched as the actors, standing next to the scanner, got the same painful treatment. 
+When a "fair" actor received a shock, the scanner showed empathy among all the volunteers. 
+In males and females alike, the images showed activation of the anterior insula/fronto-insular cortex (AI/FI) and anterior cingulate cortex (ACC). Previous research has showed that these parts of the brain cause the feeling of  distress when one sees someone else in pain.
+When an "unfair" actor got a shock, the AI/FI and ACC lit up again among most female volunteers. But amongst the men these empathic areas showed no increase in activity. 
+Reward centre activated in men
+Men who watched "unfair" actors suffering did show an activation of their nucleus accumbens, the part of the brain associated with the satisfaction of reward. This activation was not seen in most female volunteers.
+Singer says the results show that fairness in social situations "shapes the nature of the emotional link we have to other people. 
+"We empathise with others if they cooperate and act fairly. But in contrast, selfish and unfair behaviour compromises this empathic link," she says. 
+Singer believes these fundamental responses at the individual level have played a key role in social evolution. 
+They would explain for instance why communities everywhere draw up laws or codes to punish or sideline those who cheat and freeload on the majority, she says.
+As for the gender difference about punishing a social offender, Singer says she could not rule out the possibility that the experiment favoured men as there was a physical rather than psychological or financial threat involved.
+Despite this limitation, she says, the results could explain the traditional job of men as society's enforcers.
+"This investigation would seem to indicate there is a predominant role for men in maintaining justice and issuing punishment," she says.
+
+Remote peoples can describe and understand geometrical concepts related to circles, triangles and parallel lines, scientists show. So, is geometry hard-wired in the brain?
+Amazonian hunter-gatherers who lack written language and who have never seen a maths book do well on basic geometry tests, researchers say in a study that suggests geometry may be hard-wired into the brain.
+Adults and children alike showed a clear grasp of concepts such as where the centre of a circle is and the logical extension of a straight line.
+This was despite not having words for these concepts, the researchers report today in the journal Science. 
+Professor Stanislas Dehaene of the College de France in Paris and colleagues tested 14 children and 30 adults of an Amazonian group called the Munduruku, and compared their findings to tests of US adults and children. 
+"Munduruku children and adults spontaneously made use of basic geometric concepts such as points, lines, parallelism, or right angles to detect intruders in simple pictures, and they used distance, angle, and sense relationships in geometrical maps to locate hidden objects," they write. 
+"Our results provide evidence for geometrical intuitions in the absence of schooling, experience with graphic symbols or maps, or a rich language of geometrical terms." 
+Geometry is an ancient field and Dehaene's team postulated that it may spring from innate abilities. 
+"Many of its propositions -- that two points determine a line, or that three orthogonal axes localize a point -- are judged to be self-evident and yet have been questioned on the basis of logical argument, physical theory, or experiment," the researchers write. 
+There was no way the Munduruku could have learned these ideas, they add. 
+"Most of the children and adults who took part in our experiments inhabit scattered, isolated villages and have little or no schooling, rulers, compasses, or maps," they write. 
+"Furthermore, the Munduruku language has few words dedicated to arithmetical, geometrical, or spatial concepts, although a variety of metaphors are spontaneously used." 
+Playing by the rules
+They designed arrays of six images, each of which contained five conforming to a geometric concept and one that violated it.
+"The participants were asked, in their language, to point to the weird or ugly one," the researchers write. 
+"All participants, even those aged 6, performed well above the chance level of 16.6%."
+The average score was nearly 67% correct, identical to the score for US children. 
+"The spontaneous understanding of geometrical concepts and maps by this remote human community provides evidence that core geometrical knowledge, like basic arithmetic, is a universal constituent of the human mind," they conclude.
+
+Soil harbours bacteria that contain antibiotic resistance genes. So is this where hospital superbugs get their protective genes from?
+Bacteria in dirt may be 'born' with a resistance to antibiotics, which could help shed light on the problem of drug-defying superbugs, Canadian researchers say.
+They tested hundreds of different bacteria found in soil and discovered that every one had some resistance to antibiotics, meaning they had evolved a mechanism for evading the effects of the drugs. 
+The findings, published today in the journal Science, could help to explain why bacteria so quickly develop resistance to antibiotics, and why drug companies must constantly develop new ones. 
+"It explains where these things come from in the first place," says Dr Gerry Wright, of Ontario's McMaster University.
+"This work could prove to be extremely valuable to the drug development process." 
+Wright's team dug up 480 strains of streptomyces bacteria and tested them for resistance to various antibiotics. 
+"Without exception, every strain ... was found to be multi-drug resistant to seven or eight antibiotics on average, with two strains being resistant to 15 of 21 drugs," the scientists write. 
+A logical place to start
+These particular bacteria do not infect people, but Wright believes the findings almost certainly apply to other species of microbes. 
+"It turns out that streptomyces make lots of antibiotics," Wright says. "Anything that ends in 'mycin' comes from streptomycin: vancomycin, streptomycin." 
+That was why they chose this group of bacteria. 
+"We were curious to see where these things might come from in the first place, so it seemed that was a logical place to start. I expect lots of these [drug-resistant] genes are peppered all over the microbial community," Wright says. 
+The scientists exposed the bacteria to known antibiotics and then searched for genes that were activated when the microbes survived. 
+"We found old mechanisms and new mechanisms," Wright says. 
+"We found a brand-new resistance mechanism to an antibiotic called telithromycin," he says, referring to Aventis' drug Ketek, which has only recently been approved in some countries. 
+Ketek was designed to overcome resistance to antibiotics, but one of the bacteria Wright tested evolved a way to prevent it from working. 
+Developing resistance
+Almost as soon as penicillin was introduced in the 1940s, bacteria began to develop resistance to its effects, prompting researchers to develop many new generations of antibiotics. 
+But their overuse and misuse have helped fuel the rise of drug-resistant superbugs.
+The US Centers for Disease Control and Prevention says 70% of infections that people get while in the hospital are resistant to at least one antibiotic. 
+Wright says his findings do not get doctors off the hook. He says they still must prescribe antibiotics only when they are needed, and stress to patients the need to use them properly. 
+Soil bacteria live in a constant kind of arms race, making antibiotics to protect themselves against other bacteria, and then evolving antibiotic resistance to evade the antibiotics made by other bacteria. 
+"Their coping tactics may be able to give us a glimpse into the future of clinical resistance to antibiotics," Wright says.
+
+Nanoparticles may rescue us from the drudgery of cleaning the bathroom
+Cleaning bathrooms could become a chore of the past with new coatings on bench surfaces, tiles and glass that do the job for you, say Australian researchers.
+Professor Rose Amal of the ARC Centre for Functional Nanomaterials and team are developing new coatings they hope will be useful for self-cleaning surfaces in homes and hospitals. 
+"If you can have self-cleaning materials, you can do the job properly without having to use disinfectants and other chemicals," says Amal, based at the University of New South Wales in Sydney.
+Tiny particles of titanium dioxide up to 20 nanometres in diameter are currently used on outdoor surfaces, such as self-cleaning windows.
+These titanium dioxide nanoparticles absorb UVA light, ultraviolet light below 380 nanometres in wavelength.
+This excites electrons and gives the particles an oxidising ability more powerful than chlorine bleach. 
+The nanoparticles can then kill microbes and break down organic compounds from vehicle and industrial emissions into carbon dioxide and water.
+Surfaces coated with the titanium dioxide nanoparticles also have another property, called 'superhydrophilicity' that helps them self-clean. This is when water does not form droplets, but rather runs straight off the surface, washing as it goes.
+Changing the activating light
+But titanium dioxide can only be activated by UVA and this is only present in sunlight, not other sources of light, like indoor light. 
+This means that to date self-cleaning coatings have been limited to outdoor surfaces.
+Amal and team have been modifying titanium dioxide nanoparticles so they can absorb light at higher wavelengths, in the visible spectrum, over 400 nanometres in wavelength.
+They have been doping titanium dioxide nanoparticles with a small amounts of other elements such as iron or nitrogen, in place of titanium or oxygen.
+Lab trials show that glass coated with the new nanoparticles can be activated by visible light from a lamp to kill bacteria Escherichia coli, and degrade volatile organic compounds.
+"If you can coat it onto a shower room, you don't have to clean the shower room that often," says Amal. "Because of the oxidising properties, fungus will also not grow on the surface."
+Outdoor coatings could benefit too
+While Amal says the self-cleaning coatings would be useful on tiles, glass screens and benches in bathrooms and hospitals, she says the nanoparticles could also be used to improve outdoor self-cleaning surfaces.
+UVA only makes up 5% of sunlight, she says, whereas the ability to use visible light would significantly increase the amount of sunlight that could be used.
+"If you use this material outdoors you can utilise more of the sunlight wavelengths," she says.
+Funding so far has been through the Australian Research Council but Amal says her team will be looking for commercial support down the track.
+She expects it will be another year before the nanoparticles will be ready for large-scale production.
+Safety considerations
+Amal says recent concerns about the toxicity of nanoparticles should not apply to those in the self-cleaning coatings because they are chemically glued to surfaces with polyethylene glycol, and so are not free to float in the air.
+"For this particular application I don't think it should be a problem," she says.
+
+A long tailfin or 'sword' scares off competitors and impresses the ladies
+Colourful aquarium fish known as swordtails, size up competitors' tailfins before fighting, US scientists show.
+Often a male just has to show his big elongated tail, which looks like a pointy sword, to scare off challengers, according to a new study in the latest issue of the journal Animal Behaviour. 
+Yet another study in the same publication concludes that female swordtails prefer male swordtails with big, striped swords. 
+Researchers even think the female fixation on these bright appendages led to their emergence in the first place, since female fondness for novel traits and bright colours appears to have preceded the appearance of male swords. 
+The finding suggests the creation of some secondary sexual characteristics may be influenced, and even controlled, by the opposite sex. For male swordtails, this characteristic is an extension of the tail or caudal fin.
+"It is not terribly rigid and cannot be manipulated very efficiently," says Dr Kari Benson, who co-authored the first paper with Dr Alexandra Basolo. "It is not useful as a weapon. It is only used as a visual signal in a fight."
+Benson, a researcher at Lynchburg College, says, "The sword might signal many things: how strong and vigorous he is, how well he ate while growing up or simply by indicating that he is large." 
+The researchers staged duels between swordtails (Xiphophorus helleri), by putting two comparably sized males with different-sized swords in a tank and then observing their interactions, which usually involved aggressive behaviour, such as chasing and biting. 
+The researchers then artificially manipulated sword size by affixing fake plastic swords to the fish. 
+Repeatedly, the male with the bigger sword won. Often all he had to do was to show his sword and then the other male slunk away.
+Basolo, from the University of Nebraska, says the loser really looks the part. 
+"His body darkens, due to a stress response, he puts his head down and he then positions himself at the periphery of the tank," she says, adding that the loser even folds in his fins. 
+Dr Brian Trainor, a researcher in the College of Social and Behavioral Sciences at Ohio State University, says:
+"One part I was a bit amazed with was that in the sword manipulation experiment; somehow the fish were able to determine their own artificial sword sizes.
+"I think people usually think that fish are not too bright. Not only were these swordtails able to assess their competitors' apparent sword length, but also they were able to compare that with their own sword length. I thought that was a cool result." 
+He even believes there is a swordtail-human link, since both species seem to have evolved traits and behaviours that do not offer apparent survival benefits. 
+The sword, for example, appears to be useless, save for its visual impact. For humans, he says possible examples include artistic abilities and senses of humour. 
+Like male fish showing off their swords to females, he suggested that these human abilities might exist, in part, to impress members of the opposite sex.
+Like the fish swords, they can also weed out competitors who may not be as talented or humourous. 
+"Our studies in swordtails show that sexually selected traits can be complex and used in multiple behavioural contexts, much like many aspects of human behaviour," he says.
+
+This hourglass-shaped crater on Mars provides more evidence that glaciers once carved the planet's surface, glaciers made from fallen snow
+Mysterious debris fields found far from the poles on Mars were made by glaciers, possibly formed just like glaciers are on Earth, by the build-up of snow, researchers say.
+The glaciers would have resembled those found on Earth in places such as Mount Kilimanjaro in Africa or the Andean peaks in South America, the researchers report in the latest issue issue of the journal Science. 
+They probably formed when Mars was tilted on its side 5 million years ago, Brown University planetary geologist Professor James Head and colleagues say. 
+Researchers were intrigued when spacecraft data showed curious rock-strewn deposits at the foot of some Martian volcanoes and mountains close to the equator. 
+These scraped-up piles of rock and sand in certain valleys and along the western flanks of the three giant volcanoes look like what is left behind by a moving glacier on Earth. 
+It is now very cold and very dry on the Mars surface, and water cannot stand in any one place on the planet for long, even as ice. 
+Researchers have speculated whether the tropical glaciers came from snow or perhaps oozed up from underground. 
+An ancient climate
+The team of US and French researchers ran climate simulations that suggest glaciers could have formed when the Sun heated up the poles, sending snow there into the atmosphere and allowing it to fall elsewhere on the planet. 
+The models predict locations for these glaciers that match many of the glacier remnants seen today. 
+"What we found was that the glaciers were formed from snow brought from the polar regions," Head says. 
+They note that Mars often has changed its tilt so that the poles face the Sun and the equator gets only oblique sunlight. 
+"Actually, it last occurred only five-and-a-half million years ago," says Dr Francois Forget of the University of Paris, who led the team. 
+Sublime, say researchers
+The Sun's rays could vapourise the snow in a process known as sublimation, also seen here on Earth.
+Winds would carry the water vapour south, up and over the soaring slopes of the Tharsis Montes volcanoes and the giant Olympus Mons volcano. 
+The vapour would cool and condense into snow, which would eventually harden into an icy glacier. 
+"The findings are important because they tell us that Mars has experienced big climate changes in the past, the kinds of climate change that led to the Great Ice Age here on Earth," Head says. 
+"The findings are also interesting because this precipitation pattern may have left pockets of ice scattered across Mars. This is good information for NASA as officials plan future space missions, particularly with astronauts."
+
+And the AM goes to ... Dr Karl, for promoting greater understanding of the application of science to daily living
+Dr Karl Kruszelnicki, the man responsible for demystifying belly button lint, has been awarded an Australia Day Honour for his work as a science communicator.
+Dr Karl's appointment as a Member of the Order of Australia (AM) is the latest in a long list of accolades for the former scientist, engineer and paediatric emergency doctor, including a 2002 Ig Nobel Prize for his belly button lint research.
+Kruszelnicki, who describes himself as "very mediocre as a scientist but pretty good at talking about it" says his real achievements have been in making a difference to people's lives.
+He tells the story of a woman who told him at a book signing that her son, once a high school drop-out and surf bum, decided to become a geneticist after listening to him on Triple J radio.
+The boy got himself a PhD and is working as a geneticist at Harvard University today.
+"Under circumstances like that I feel that I have done my work," Kruszelnicki says.
+"I used to be a medical doctor and I didn't realise it at the time, but the reason I was doing it was to liberate people from what ails them or to help them get to the next stage, like a conduit.
+"So I think that's what [the AM] is for. Alternately it might be for my groundbreaking work on belly fluff."
+The secret history of Dr Karl
+Kruszelnicki was born in Sweden, across the river from Elsinore where Hamlet trod the corridors of his castle in Shakespeare's play.
+At school he was teased for having a weird surname and he grew up to work in a variety of jobs including physicist, labourer, roadie and TV weatherman.
+Today he's a popular media personality and a best-selling author.
+Ask about the least known fact about him besides his middle name (it's Sven), and he tells you that he test-drives four-wheel drives and is an avid autograph collector who has the signatures of three of the 12 moon walkers. 
+He also subscribes to A$10,000 (US$7500) worth of scientific literature.
+Kruszelnicki says the most important scientific discovery is that you can't mix sewage with drinking water, the most over-rated is the internet and the biggest unanswered question is why the Moon is larger on the horizon.
+The most way-out theory that may one day become reality?
+That one day genetic engineering will allow us to travel through space in the form of a giant magnetic vapour cloud.
+"And you'll still be able to have sex," he says.
+He's also learning to stand up on his Malibu surfboard. Obviously he'll be applying the most complex laws of physics to the task.
+"It's called not falling over," he says.
+Other Australia Day Honours recipients include:
+&bull; Professor Ian Hickie (AM), clinical advisor beyondblue, for service to medicine in the development of mental health initiatives
+&bull; Dr Jeanne Collison (AO), as a pioneer of cardiac bypass techniques through the development of the first Australian heart-lung machine
+&bull; Dr Ian Brooker (AM), for services to botany, including research leading to the identification and classification of the genus Eucalyptus; and
+&bull; Dr George Bennett (AM), for his work in celestial navigation and positional astronomy.
+
+The Fab Tree Hab weaves together branches to form living archways
+Growing a home from living trees instead of building a home from felled timber is the goal of an architect from the Massachusetts Institute of Technology. 
+Dr Mitchell Joachim, part of the MIT Media Lab's Smart Cities Group, along with ecological engineer Dr Lara Greden and architect Javier Arbona, propose a home that is actually an ecosystem. 
+The Fab Tree Hab goes beyond sustainable housing and so-called green design, building with materials that have a low impact on the environment and human health. 
+"Not only does it do zero damage, but it will hopefully clean the air," says Joachim. 
+The habitat is based on an ancient gardening method known as pleaching, which weaves together tree branches to form living archways, lattices or screens. 
+In Joachim's vision, the exterior of the living house is shaped over the course of several decades into a protective crisscross of vines, interspersed with soil pockets and growing plants. 
+A clay and straw composite fills in the gaps to insulate against the cold and heat and keep out moisture. 
+He proposes constructing windows manufactured from soy-based plastics that would flex with the home as it grows. 
+Gathering water
+Water would be gathered in a roof-top trough and circulate by gravity through the house, where it would be used by the inhabitants, filtered through a garden, and purified in a pond containing bacteria, fish, and plants that consume organic waste. A composting system would treat human refuse.
+Water would also serve to hydrate the plants and the tree itself, which would give off water vapour naturally during transpiration and cool the shelter. 
+The Fab Tree Hab would also rely on the Sun for heat. Large, south-facing windows would absorb warmth in the northern hemisphere's winter, while windows located on the shady side at ground floor would draw in cool breezes during hot months. 
+Grow your own furniture
+"The living house would be the Holy Grail of this art form," says Richard Reames, an Orgeon-based arborsculptor and author of the book How to Grow a Chair. 
+Reames uses grafting and pleaching techniques to grow living chairs, benches and tables. 
+Joachim's dream is to plan an entire community based on the living house design, but before that can happen, he will need to conduct a year or two's worth of sociology and feasibility studies. 
+In the meantime, he is designing a house in California that will be constructed from 50% recycled and reconstituted materials and 50% living elements. 
+The project is called MatScape and Joachim sees it as an experimental step toward the ultimate living house.
+
+Navigating bubble wrap: part of research that may one day help to design space exploration robots
+Crayfish don't just blunder around in the dark bouncing off rocks but use a sophisticated sense of touch to form detailed mental images of their surroundings, an Australian researcher says.
+Professor David Macmillan of the University of Melbourne has previously piqued the interest of NASA, which has applied his earlier work on the crayfish, or yabby (Cherax destructor), to developing tiny space exploration robots.
+Macmillan says just as humans looking for the bathroom in the middle of the night grope around with their hands, yabbies in dark or murky waters use their antennae to orientate themselves.
+They also use chemosensory receptors all over their bodies that allow them to detect chemicals in the water from food, mates or predators.
+"We're trying to find out how crustaceans work out what their world is like," he says.
+Yabbies are not renowned for having large brains, but Macmillan says his research, published in the current issue of the Journal of Experimental Biology, shows the crustaceans have an acute sense of touch that helps them to get around.
+"People have made lots of assumptions that they're not that smart and they don't know what's going on out there but increasingly [we're] finding that they actually put together some pretty sophisticated pictures," he says.
+Bubble wrap or sandpaper?
+In the study Macmillan and colleagues put the crayfish into arenas containing different types of surfaces and structures including bubble wrap and sandpaper.
+"Basically we asked the animals to tell us whether they could tell the difference," he says.
+"What we're seeing is that they change their behaviour according to the texture of surfaces."
+He says his team is the first to demonstrate that yabbies can discriminate between textures.
+Crayfish in space
+Macmillan's research feeds into the field of biomimetics, where designs found in nature are used in robotics.
+A few years ago, he travelled to the US where he met NASA scientists developing miniature, independently moving robots to discuss his work on how yabbies move their tails.
+Macmillan has just completed more work suggesting yabbies can analyse particular spaces before they enter them, and can even recognise places they've been before, and other crayfish.
+"We now think we've got evidence that they can do very sophisticated analyses on a space before they even get into it, they can detect vibrations and they can remember what they've experienced before," he says.
+
+Pericles probably died of typhoid fever, as did as many as one-third of his fellow Athenians
+Modern DNA analysis of ancient dental pulp suggests that typhoid fever caused the plague that helped to end the Golden Age in Athens, scientists say. 
+The DNA collected from teeth from an ancient Greek burial site is similar to a modern organism that causes typhoid fever, an infection spread by contaminated food or water. 
+"Studying the historical aspects of infectious disease can be a powerful tool for several disciplines to learn from," says Dr Manolis Papagrigorakis of University of Athens, a co-author of the study published in the International Journal of Infectious Diseases.
+"We believe this report to be of outstanding importance for many scientific fields, since it sheds light on one of the most debated enigmas in medical history." 
+Up to one-third of Athenians are thought to have died from the plague that spread to Greece from Ethiopia, Egypt and Libya in 430-426 BC. 
+Several diseases including smallpox, bubonic plague, anthrax and measles have been suggested as the cause of the plague, one of whose most prominent victims was the Athenian Golden Age leader Pericles. 
+The plague is thought to have changed the balance of power between Athens and Sparta, ending Athenian dominance.
+The scientists describe how they extracted DNA from a mass burial pit in a cemetery dating back to the time the plague struck Greece. 
+Papagrigorakis and his team say the DNA sequences resembled Salmonella enterica serovar Typhi, the organism that causes typhoid fever.
+
+How much old research is based on fraud? Details are emerging about the latest case, which involves papers in three medical journals
+A Norwegian mouth cancer specialist has admitted to fabricating research data published in several international scientific magazines, in the latest fraud case to rock the medical research world. 
+A doctor at the Institute for Cancer Research at the Norwegian Radium Hospital, Dr Jon Sudb&oslash;, has confessed to forging data used to document research published last October in The Lancet as well as in two other articles. 
+The revelation comes on the heels of the disclosure that South Korea's celebrated cloning pioneer Professor Hwang Woo-Suk had faked research papers claiming breakthroughs in stem cell research. 
+Suspicion that Sudb&oslash;, 44, had forged data in The Lancet article surfaced earlier this month and several investigations have been launched into his conduct. 
+"He has indicated that in addition to the article in The Lancet, two of his other articles contained information in which the conclusions have no basis," says Sudb&oslash;'s lawyer Erling Lyngtveit. 
+The two other articles appeared in the New England Journal of Medicine in April 2004 and the Journal of Clinical Oncology in March 2005. 
+"It appears that he started cheating a little bit, and then the deception got completely out of control in his last article in The Lancet," the lawyer adds. 
+Made-up study
+In The Lancet article, the doctor maintained that anti-inflammatory drugs like aspirin were efficient in preventing mouth cancer, but they also increased the risk of cardiovascular disease. 
+He based this conclusion on data from 908 fictitious patients, 205 of whom had been given the same date of birth. 
+"This had nothing to do with money," Lyngtveit insists. 
+"In different circumstances, his motives would be perceived as positive since they are what helps research to move forward: the desire to contribute to something, the yearning for fame and glory," he says, adding however that "this got completely out of hand". 
+In Sudb&oslash;'s article in the New England Journal of Medicine, he claimed that the resection of the first cancerous cells in the oral cavity did not have an impact on the mortality rate in patients. 
+According to his lawyer, he now admits he did not have the mortality statistics to back up that claim. 
+Sudb&oslash;'s article in the Journal of Clinical Oncology meanwhile discussed the possibility of calculating which heavy smokers would contract mouth cancer. 
+He has now admitted that he had only taken blood tests from some of the patients, and not all of them as previously claimed, to check if they had continued smoking, Lyngtveit says. 
+Over the past decade, Sudb&oslash; has published 38 articles in international scientific magazines, but his lawyer insists that "the forgery only occurred in three articles". 
+"Sudb&oslash; acted alone. His co-authors contributed to the articles in good faith," he adds. 
+The case has contributed to further weakening faith in research published in scientific reviews after the widely publicised Hwang scandal. 
+In 2005 Hwang claimed to have derived 11 stem cell lines tailored to specific patients, which are believed to have the potential to reduce the risk of rejection of new organs. In 2004, he said he had derived a stem cell from a human embryo. 
+But after a month-long probe, a panel of experts from Seoul National University found that Hwang had created no stem cells of any kind and that his research data was fabricated. 
+US research journal Science retracted Hwang's papers last week. 
+The Lancet meanwhile stated on its website earlier this week that "pending clarification, we now issue an expression of concern about the article by Sudb&oslash;".
+
+Alkaloids found in magic mushrooms act on the brain to produce changes in perception and hallucinations
+An Australian researcher has developed a new test for mushrooms that produces a glowing light if they contain the hallucinogenic ingredients that make them 'magic'. 
+Several species of magic mushroom grow in Australia, mainly in New South Wales, Victoria and South Australia. 
+Nicole Anastos, who did the research for her PhD at Deakin University, describes her work in the latest issue of the Journal of Forensic Sciences.
+She applied the method to three species of magic mushroom Psilocybe subaeruginosa, Hypholoma aurantiaca and Panaeolina foenisecii, provided by the Royal Botanic Gardens Melbourne.
+The technique uses chemiluminescence, a light reaction that occurs when two chemicals react, to detect psilocybin and its metabolite psilocin. These are the serotonin-like psychoactive ingredients in magic mushrooms.
+Magic happens
+Not all molecules exhibit chemiluminescence. But mix psilocin with acidic potassium permanganate and psilocybin with ruthenium and magic happens.
+Anastos says the technique can detect extremely low levels of psilocin, making it the most sensitive test there is and the first time chemiluminescence has been applied to magic mushrooms.
+"In the literature there's quite a few pieces published on the analysis of psilocin and psilocybin in magic mushrooms but the analysis time is quite long in some of them," she says.
+"We wanted a rapid method to detect these alkaloids. To date it's the most sensitive method published."
+Anastos soaked ground up samples of mushroom in methanol and separated the chemical components using high performance liquid chromatography (HPLC) before running the chemoluminescence test.
+A do-it-yourself test kit?
+Anastos says she hopes her research will be picked up and developed for use by the police.
+It could possibly also form the basis of a home magic-mushroom test kit or a urine test, she says.
+Associate Professor Michael Dawson, head of chemistry, materials and forensic sciences at the University of Technology Sydney says Anastos' work is interesting chemistry.
+But he says it doesn't offer any real advantage over existing tests.
+Mass spectrometry or ultra violet absorption produced equally good results when testing for psilocin and psilocybin in magic mushrooms, he says.
+"Once you've separated the mixture into its individual components ... there's a whole host of detection methods."
+
+Vikings are continuing to surprise us. They didn't have horned helmets, as this image suggests. And now it seems they filed their teeth, possibly as a status symbol
+Viking warriors filed deep grooves in their teeth, and they probably  had to smile broadly to show them off, according to new finds in four major Viking Age cemeteries in Sweden. 
+Caroline Arcini of Sweden's National Heritage Board and colleagues analysed 557 skeletons of men, women and children from 800 to 1050 AD. 
+She discovered that 22 of the men bore deep, horizontal grooves across the upper front teeth.
+"The marks are traces of deliberate dental modifications ... they are so well-made that most likely they were filed by a person of great skill," Arcini writes in the American Journal of Physical Anthropology, a journal of the American Association of Physical Anthropologists.
+Traces of teeth mutilation have been found in all parts of the world except Europe, with the practice reaching its peak from 700 to 1400 AD, during the height of the Viking Age.
+The Vikings were the first Europeans to have displayed this custom, perhaps because they picked it up during their travels.
+"This discovery is important as it shows that signs of cultural contact may happen between people over vast distances," Arcini says.
+However, the reason for and the importance of the furrows remain mysteries.
+"The only things that the people have in common are that they were men and that majority had died when they were quite young. The filed furrows were made in more or less the same area of the teeth in all individuals," Arcini says.
+The marks were cut deep into the enamel and occurred often in pairs or triplets.
+"To show their furrows, the individuals would have had to smile quite broadly," Arcini says.
+The researcher speculates that the marks could have been some sort of decoration or a badge to indicate class or military rank.
+"Maybe they were warriors, although no skeletal injuries have been detected," Arcini says.
+A status symbol? 
+Pia Bennike, at the University of Copenhagen's biological anthropology laboratory, agrees:
+"They did it on purpose, to mark that they belonged to a special group. Or maybe they were slaves. This is a very unique and interesting find."
+One hypothesis is that they could show an individual's ability to resist pain. They could have also represented some kind of achievement.
+"Maybe this is the explanation for multiple furrows or deeper ones," Arcini says.
+The tools that the Vikings used for handicrafts were made both of iron and stone. An experiment on a medieval tooth showed that with a lot of force and a file of steel, it takes about 20 minutes to cut a mark like the those of the Vikings in the enamel.
+"How long it took on a living person is really difficult to know. Even if the filing did not hurt, it most certainly must have been unpleasant," Arcini says.
+
+The new planet may look like this, a rocky-icy world circling a red dwarf star
+Astronomers have discovered the most Earth-like planet so far, close to the centre of our galaxy.
+The international team says the planet's relatively small size and large orbit imply a rocky-icy composition with a thin atmosphere.
+The discovery, involving a global network of telescopes and reported in today's issue of the journal Nature, is good news for astronomers searching for planets outside our solar system that may support life.
+"This discovery is a strong hint that these lower-mass objects are very common," says lead author Dr Jean-Philippe Beaulieu from the Institut d'Astrophysique de Paris.
+The discovery of OGLE-2005-BLG-390Lb also backs current theoretical models of planetary formation, the scientists say.
+These models predict finding planets the size of Earth to Neptune orbiting red dwarf stars, small cool stars, between one and 10 times the distance from the Earth to our Sun.
+The new planet has mass more than five times that of Earth and orbits a red dwarf at more than two-and-a-half times the distance between the Earth and the Sun.
+This makes it the first relatively small extrasolar planet discovered not huddled close to its parent star.
+The planet is about 28,000 light years away, near the centre of the Milky Way, and was discovered using a technique astronomers say is better at finding smaller planets.
+Hunting for extrasolar planets
+Most extrasolar planets discovered have been 'hot Jupiters' or gas giant planets in small orbits, detected by the gravitational 'wobble' they induce in the parent star.
+"That technique is sensitive to massive planets orbiting nearby stars. But the microlensing method ... can detect much smaller planets orbiting at larger distances around distant stars," says New Zealand's Dr Michael Albrow from the University of Canterbury.
+Albrow is a founding member of the PLANET collaboration, which found the planet, one of the three microlensing collaborations involved from 32 institutions in 12 countries.
+Dr Andrew Williams from Australia's Perth Observatory explains how microlensing works.
+"The gravity of a dim intervening star acts as a giant natural telescope, magnifying a more distant star, which brightens temporarily. A small 'defect' in the brightening reveals the existence of a planet around the lens star."
+Because the chances of exact alignment are very rare, astronomers continuously monitor dense star fields such as the galactic centre, which is best seen from the southern hemisphere.
+The Japanese-New Zealand Microlensing Observations in Astrophysics group supplied extra data.
+The group happened to be testing the world's largest dedicated microlensing telescope at the time, a 1.8 metre telescope at Mount John University Observatory in Tekapo, New Zealand.
+
+The adult female is just 7.9 millimetres long when sexually mature
+The smallest fish in the world has been found lurking in the peat wetlands of Southeast Asia, say scientists.
+Dr Maurice Kottelat of the National University of Singapore and team report their discovery online ahead of print publication in the Royal Society journal  Proceedings B.
+The record-busting newcomer, Paedocypris progenetica, is skinny and transparent, and a distant cousin of the carp, the researchers say.
+The elusive fish lives in highly acid peat swamps on the Indonesian island of Sumatra and in the Malaysian part of Borneo that are threatened by forestry and agriculture. 
+The scientists needed a special stereoscopic microscope to accurately measure the fish. 
+The smallest adult specimen they netted was a mature female, found in Sumatra, that came to just 7.9 millimetres from nose to tail.
+This makes her not only the world's smallest fish but also the world's smallest vertebrate.
+She nudged out the previous record holder, a marine fish of the western Pacific called the dwarf goby (Trimmatom nanus), which comes in at 8 millimetres at sexual maturity. 
+Kottelat says P. progenetica has "a very rudimentary skull", which leaves the brain exposed.
+
+Maybe he should have had sex
+Nervous public speakers should first have penetrative sex to ease the stress, according to a UK study.
+But masturbation is unlikely to have the same effect, the study published in the latest issue of the journal Biological Psychology suggests.
+Professor Stuart Brody, a psychologist at the University of Paisley, compared the impact of different sexual activities on blood pressure when a person later undergoes a stressful experience. 
+Brody asked 24 women and 22 men to keep a diary of their sexual activities for two weeks. 
+The volunteers then underwent a stressful ordeal that involved making a speech in public and doing mental arithmetic out loud. 
+Volunteers who had had penetrative sex during the previous week or so had the least stress, and their blood pressure returned to normal fastest after their test.
+Penetrative sex was far more effective in this regard than masturbation or oral sex.
+But those who had abstained completely from any sexual activity had the highest stress levels and blood pressure of all.
+Brody also did a psychological profile of the volunteers to see whether they had an anxious or neurotic character, and evaluated their work stress and satisfaction with their partners.
+Even when such factors were taken into account, sexual behaviour was clearly the best explanation for the stress responses.
+"The effects are not attributable to the short-term relief afforded by orgasm but, rather, endure for at least a week," Brody told New Scientist magazine.
+He believes that penetrative sex may release a special 'pair-bonding' hormone called oxytocin, which accounts for the calming effect.
+
+Adding another electrode to this ion engine improves fuel efficiency, tests show, promising faster space travel
+A new ion engine that promises to propel spacecraft faster and further is four times more fuel efficient than the best available, scientists say.
+They say the results of recent tests suggest the engine, the Dual Stage Four Grid Thruster (DS4G), would reduce the time for craft to reach Mars or Pluto and beyond.
+Dr Orson Sutherland and team at the Australian National University's Space Plasma Power and Propulsion Group designed and built the engine with the European Space Agency (ESA).
+Sutherland says laboratory tests show the DS4G it is four times more fuel efficient than the best ion engines available and 10 times more fuel efficient than used to propel ESA's SMART-1 Moon mission.
+"The underlying technology has been around for 40 years," he says. "All we did with the DS4G is to add some extra components which basically gave it a 10-fold improvement."
+Sutherland says missions to Pluto and the Kuiper Belt would be "quite easily" made, with trips out beyond the solar system also more feasible.
+"All of that within the working lifetime of a mission scientist," he says.
+Another option is the new engine could help take heavier missions to shorter distances such as the Moon or Mars.
+How it works
+A standard ion engine works by using electrodes to extract ions from plasma, in this case heated xenon gas.
+The ions are focused into beams that accelerate through tiny holes in the electrodes and thrust metres out into space, propelling the spacecraft in the opposite direction.
+
+Clusters of magnesium, zinc and copper atoms could be the key to strengthening lightweight metals
+An Australian PhD student has taken the first pictures of clusters of metal atoms, which could be the key to tailor-made alloys that are light, strong, durable and flexible.
+Peter Liddicoat of the  University of Sydney will present the digital images at a microscopy conference in Sydney next month. 
+Liddicoat analysed the atomic structure of a lightweight alloy used in the aerospace industry.
+The alloy is made of aluminium, zinc, magnesium and copper heated to 460°C before undergoing a rapid hardening process. 
+Hardening involves quenching the alloy in water and then reheating it to 150°C. After 60 seconds at this temperature, the alloy is twice as hard.
+Although this hardening process has been used for 50 years, Liddicoat says no one knows how it works.
+"Making metal is still a bit of a black art. It's like cooking," he says. "[This work is] just trying to get a bit of science back into it."
+Some time ago, his PhD supervisor, Professor Simon Ringer proposed a theory that small clusters of atoms in the alloy could be responsible for the hardening.
+And Liddicoat is the first to image them.
+First, decompose your alloy
+Liddicoat imaged the clusters using strong electromagnetic fields at very low temperatures to 'decompose' the alloy. 
+"When you decompose this material you actually rip the atoms off one by one," he says. "It's actually a very delicate process."
+A 3D digital image of the alloy and its atoms is then made by computer.
+Liddicoat says he is "pretty excited" to have imaged these clusters and the next step is to confirm that these clusters are responsible for the alloy's hardening.
+He hopes to work out how the atoms arrange themselves by taking snapshots of the alloy over time.
+And he wants to characterise the clusters: the precise combination of atoms that makes them up, the shape of the clusters and how many there are per unit volume of the alloy.
+Tailor-made alloys
+Liddicoat hopes this will one day make it possible to create materials with specific degrees of flexibility, durability and tensile strength.
+"If you understand what they are then ... you might be able to create the conditions to create these things," he says.
+
+An ancient ancestor of today's crocodiles looks like a cross between an ostrich and a dinosaur
+The discovery of a six-foot-long, bipedal and toothless fossil in a museum basement suggests crocodile ancestors looked like some bird-like dinosaurs that lived millions of years later, scientists say.
+The crocodile ancestor fossil, found in the basement of New York's American Museum of Natural History, is an example of how similar body types can evolve several times over.
+A museum team excavated the 210-million-year-old fossil in the 1940s from the Ghost Ranch Quarry in New Mexico.
+This site has produced numerous fossils of Coelophysis, small, carnivorous dinosaurs that lived in the Triassic period. 
+As scientists thought Coelophysis was the only vertebrate fossil in the quarry, the crocodile kin sat forgotten in storage and lodged in a slab of rock for nearly 60 years. 
+When graduate student Sterling Nesbitt opened the plaster jacket encasing the find in 2005, he saw an articulated fossil that closely resembled bird-like dinosaurs called ornithomimids, or ostrich dinosaurs, that lived 80 million years later. 
+Along with Dr Mark Norell, curator of the museum's palaeontology division, Nesbitt reported the finding in the Proceedings of the Royal Society B. 
+Part bird, part dinosaur
+The creature had large eyes, a beak, a long tail and no teeth. Walking on two feet with its tail erect, it lived at the end of the Triassic with some of the earliest dinosaurs. 
+"We don't know what the animal ate because it has a beak, and extant animals with beaks can eat almost anything," says Nesbitt. 
+While the skull and the skeleton were almost identical to those of ostrich dinosaurs, the ankle is typical of an ancient group of reptiles called crocodilians, which includes today's crocodiles and alligators. 
+The new animal was named Effigia okeeffeae, after the Latin word for ghost, referring to the fact that it was invisible to science for so long. Its name also honours the artist Georgia O'Keeffe, who lived near the quarry. 
+"This is one of the most specialised extinct relative of crocodilians yet known, and shows that the 'duck-billed' head that later evolved in ornithomimid dinosaurs first appeared, independently, in crocodilians relatives," says James Clark, associate professor of biology at the George Washington University in Washington DC. 
+"This exciting find tells us once again that crocodilians and their relatives were at one time much more diverse than they are today." 
+The fossil has also turned a keystone for identifying other close relatives to Effigia, says Norell.
+The researchers re-examined some isolated Triassic reptile specimens and noted that Effigia also resembles early theropods, two-legged carnivore dinosaurs. 
+They concluded that Effigia-like animals were common in most of the Triassic sediments of western North America. 
+This would suggest that creatures like the newly discovered fossil dominated what is now the Americas, and that dinosaur evolution only took off after Effigia went extinct. 
+Clark agrees. "The fossil record of the Triassic and Jurassic shows that dinosaur diversity did not take off until after the extinction event at the end of the Triassic, which included large-bodied crocodilian relatives such as aetosaurs, phytosaurs, and rauisuchians, as well as the smaller Effigia," he says.
+
+Cars run on ethanol would make us less dependent on fossil fuels. But does ethanol meet both energy and environmental goals?
+Ethanol fuel is more energy-efficient than some experts had realised and it is time to start developing it as an alternative to fossil fuels, researchers say.
+While some critics say the push for ethanol is based on faulty science and mostly benefits the farm lobby, several reviews and commentaries published in today's issue of the journal Science argue otherwise. 
+"We find that ethanol can, if it is made correctly, contribute significantly to both energy and environmental goals. However, the current way of producing ethanol with corn probably only meets energy goals," says Dr Alexander Farrell at the University of California, Berkeley. 
+Farrell and colleagues looked at six studies used to argue for and against the development of ethanol as an energy source.
+"One of the main purposes is to explain why the studies found in the literature have such divergent results," Farrell says.
+"Some of the studies use what appear to be obsolete data or data whose quality cannot be verified."
+Currently, ethanol is not a significant source of fuel, but is blended with petrol. Environmentalists hope it could be developed as a cleaner source of fuel than oil or gas. 
+"The 15.5 billion litres of ethanol blended into gasoline in 2004 amounted to about 2% of all gasoline sold by volume and 1.3% of its energy content," the researchers write. 
+Pollution and greenhouse gases?
+Farrell says it is possible to put ethanol in a car and run it, but making ethanol using current technology is expensive and contributes to pollution and greenhouse gases.
+"[The environmental cost] comes entirely from making fertiliser, running the tractors over the farm and operating the biorefinery," Farrell says. 
+Better methods now being investigated would use the woody parts of plants, using what is known as cellulosic technology to break down the tough fibres. 
+"Ethanol can be, if it's made the right way with cellulosic technology, a really good fuel," says Farrell, an assistant professor of energy and resources. 
+"At the moment, cellulosic technology is just too expensive. If that changes, and the technology is developing rapidly, then we might see cellulosic technology enter the commercial market within five years." 
+Fuel, food and chemical from biomass
+Writing in the same journal, scientists from Imperial College London, Georgia Tech and Oak Ridge National Laboratory in Tennessee say they have teamed up to find ways to make a facility to do that. 
+Their facility would make a range of fuels, foods, chemicals, animal feeds, materials, heat and power.
+It would use biomass, a collection of renewable plant matter and biological material such as trees, grasses and agricultural crops.
+"We're looking at a future for biomass where we use the entire plant and produce a range of different materials from it," says Dr Charlotte Williams of Imperial's chemistry department.
+"Before we freeze in the dark, we must prepare to make the transition from nonrenewable carbon resources to renewable bioresources," her team writes. 
+An oil industry expert says it is possible.
+"Credible studies show that with plausible technology developments, biofuels could supply some 30% of global demand in an environmentally responsible manner without affecting food production," says Professor Steven Koonin, chief scientist for BP in London, writes in a commentary. 
+"To realise that goal, so-called advanced biofuels must be developed from dedicated energy crops, separately and distinctly from food."
+
+The diet stresses lashings of meat and limits fruit and vegetables
+The high-protein Atkins diet has caused a "life-threatening complication" for a woman who strictly followed the diet, say US doctors.
+Dr Tsuh-Yin Chen of Lenox Hill Hospital in New York and team report the case in today's issue of The Lancet.
+The Atkins diet stresses lashings of meat, butter and other dairy products - high-fat foods typically limited in classic diets - but cuts potatoes, rice and pasta to negligible levels and greatly limits intake of fruit and vegetables.
+The diet's premise is that a carbohydrate-starved body will start to burn up stored fat cells, a process called ketosis. 
+Chen and team report seeing a 40-year-old obese woman a month after starting the Atkins diet.
+She reported losing 9 kilograms after eating only meat, cheese and salads, supplemented by minerals and vitamins sold by Atkins Nutritionals, the company founded by diet pioneer Robert Atkins in 1989. 
+The woman was admitted for emergency treatment, complaining of a shortness of breath, nausea and repeated vomiting that had lasted several days, as well as mild gastric pains.
+Urine and blood analysis showed she had severe ketoacidosis, a condition in which dangerously high levels of ketone acids build up in the liver as a result of a depletion of the hormone insulin. 
+Ketoacidosis, which is more usually seen among diabetics and victims of starvation, can lead to a coma. 
+The patient responded well to rehydration and glucose infusion and left hospital after four days. 
+"Our patient had an underlying ketosis caused by the Atkins diet and developed severe ketoacidosis," say the researchers, adding that mild pancreatitis or stomach infection may have contributed to the problem. 
+"This problem may become more recognised because this diet is becoming increasingly popular worldwide." 
+Diet "not nutritionally balanced"
+In a commentary also published in The Lancet, Dr Lyn Steffen and Jennifer Nettleton of the University of Minnesota's School of Public Health blast the Atkins diet as "clearly ... not nutritionally balanced". 
+"Low-carbohydrate diets for weight management are far from healthy, given their association with ketosis, constipation or diarrhoea, halitosis, headache and general fatigue to name a few," they say. 
+"These diets also increase the protein load to the kidneys and alter the acid balance of the body, which result in loss of minerals from bone stores, thus compromising bone integrity." 
+Steffen and Nettleton add: "Our most important criterion should be indisputable safety, and low-carbohydrate diets currently fall short of this benchmark." 
+The Atkins diet builds on a long history of low-carbohydrate diets that reaches into the 19th century. More than 45 million copies of Atkins diet books  have been sold, and the impact of the fad has been far-reaching, elevating meat and "low-carb dishes" over pasta, potatoes and rice. 
+Atkins Nutritionals emerged from bankruptcy protection earlier this year, specialising as a company that sells low-carb bars and shakes. 
+A US firm that handles the company's relations with the media says it cannot comment on the paper published in The Lancet.
+
+The findings suggest that drinking water might help decrease your sensitivity to pain
+Going without a drink can make you more sensitive to pain, a study has found.
+Australian pain expert Dr Michael Farrell of the Howard Florey Institute in Melbourne and team report their findings in today's issue of the Proceedings of the National Academy of Sciences.
+"This is another demonstration of the plasticity of pain responses," he says.
+"In this particular instance a mild perturbation of electrolyte levels, which is fundamentally what gives rise to thirst ... is enough to modify the pain response."
+Farrell and team studied the relationship between thirst and pain in 10 people.
+The study participants had pressure applied to their thumbs to induce mild pain and were given saline injections to stimulate thirst.
+The researchers used a PET or positron emission tomography scan to measure blood flow in the brains before and after.
+The results showed that people who were thirsty felt more pain.
+Two regions of the brain (the pregenual cingulate and ventral orbitofrontal cortex), which were not turned on by either input alone, lit up suggesting a location where the two sensations were being integrated.
+The researchers did not find that pain affected thirst levels, but Farrell says this could be because the participants were not made very thirsty in the first place and any decrease would have been hard to measure.
+The logic behind the findings
+Farrell says the team had speculated there might be circuits in the brain that allow one sensation to modulate another, which is important from the point of view of survival.
+Hunger, thirst, tiredness and pain, for example, don't conveniently happen at the same time, he says, so it's important for the body to prioritise.
+He says pain is accentuated because it is more important to survival than mild thirst.
+"The sensation with the most immediate implications for survival is pushed to the forefront of attention," says Farrell.
+Drinking to cut pain?
+Farrell says the findings suggest it could be wise for people who are about to go through a painful experience should drink more water beforehand. 
+He says evidence from different types of studies also support this relationship between drinking water and pain.
+But could people deliberately use dehydration to maximise pain, say via torture?
+Not necessarily, says Farrell.
+"We suspect if they got dehydrated enough that the overwhelming sense of thirst would probably make pain less rather than more."
+Previous studies in rats have shown that mild thirst makes the animals feel more pain but severe dehydration actually dulls pain, he says.
+And he says, this too makes sense from the point of view of survival.
+If you were very dehydrated it would pay to suppress pain because it might get in the way of your search for water, he says.
+Ethical limitations of the study
+Farrell says it would have been too hard on the study participants, who already spent up to three hours on the table, to test whether drinking decreased pain.
+"They've got this plastic mask holding their head perfectly still and they've got both arms spread out, one of them with a hypertonic solution going into one vein and the other one getting radioactive isotopes. It would have been intolerable," he says.
+And testing whether dehydration would have dulled pain would be similarly tricky ethically, he says.
+
+Relatives of this snail left an unusual evolutionary trail. They may have hitched a ride around the world on the back of migratory birds to form new species on distant islands
+The animal kingdom's least-likely island-hopping creatures - land snails - have managed to jump from Europe to the Azores, scientists say.
+They then jumped some 9000 kilometres of snail-dissolving ocean to the isolated Tristan da Cunha island group, deep in the South Atlantic.
+The remarkable and mysterious dispersal abilities of the land snails, belonging to the Balea genus, have resulted in the evolution of eight new Tristan island species.
+It was the snails' genes that gave away their ancestors' immigration patterns, according to a study in the latest issue of the journal Nature. 
+Researchers still don't know how the snails made the trip.
+One possibility is that a tiny juvenile member of the hermaphroditic snail became stuck in the feathers of a wading bird that was blown off course and ended up on the islands, says Dr Richard Preece, of the University of Cambridge, a co-author on the Nature paper.
+"The problem is that these are land snails and they don't like salt, as you well know," says the University of Hawaii's Dr Robert Cowie, a snail researcher who is working on a very similar, but far larger, study on the dispersal history of Pacific land snails.
+Salt water pretty much rules out one common way for animals and plants to reach islands: by raft.
+In fact, it was Charles Darwin who tested whether self-sealed land snails could survive on logs or other floating debris. In the end, he preferred the idea that birds brought them.
+But there is a third possibility, says Cowie. The snails might have flown without birds.
+There have been wind tunnel studies of how far juvenile snails from Greek islands can blow in the wind. It has been calculated that small snails can be blown more than 16 kilometres.
+"In the Pacific we have even tinier snails," says Cowie. What's more, most of them live in trees, where they could conceivably be caught on a freed leaf during a hurricane and carried for thousands of miles.
+"So there's that scenario, which makes it even more possible to imagine flying snails."
+To get the present numbers and diversity of snails on the Hawaiian islands, for instance, Cowie and his colleagues figure that they'd only need one snail-carrying, hurricane-driven leaf to reach the islands every 10,000 years.
+As for the Tristan da Cunha island snails, it could be birds or storms that brought them there, says Cowie. At present, there is no easy way to find out.
+
+The genetic code of marsupials has been documented for the first time with the sequencing of the opossum genome
+The sequencing of the first marsupial genome has allowed researchers to trace the immune system of mammals back to what they've dubbed an ancestral "immune supercomplex".
+And the research suggests that the human immune system in its present form is a surprisingly recent innovation, says Australian evolutionary biologist Dr Kathy Belov from the University of Sydney, who led the international team.
+The grey short-tailed opossum (Monodelphis domestica), found in South America, is the first marsupial to have its genome sequenced.
+The sequencing was done at the Broad Institute in the US and the current research represents the first gene cluster characterised.
+Belov and colleagues from Australia, Europe and the US report their research on the region, known as the major histocompatibility complex (MHC), in the journal Plos Biology today.
+"The research has helped form a picture of what that region would have looked like in ancestral mammals," Belov says.
+That picture shows a central complex of immune genes that have since dispersed and are now scattered around a variety of chromosomes.
+A supercomplex of immunity
+"We're finding that the opossum has a couple of genes in their MHC which aren't in the MHC of other species, and other species have genes in their MHC which aren't in other species," Belov says.
+"By tracing it back we can see that originally there was this big cluster of immune genes ... and over time those genes have moved out of this central complex.
+"It suggests there was one big immune gene supercomplex in a mammalian ancestor.
+"It's a bit like a dinosaur in that we only know that it's around from the fossil evidence."
+Belov will also examine the MHC in the platypus, the first monotreme, or egg-laying mammal, to have its genome sequenced.
+Understanding immune systems will help to conserve vulnerable species, Belov says.
+Mammal evolution
+It's believed that the first monotreme appeared about 210 million years ago and marsupial and placental mammalian lineages separated around 180 million years ago.
+South American and Australian marsupials split about 70 million years ago with the break up of the southern supercontinent Gondwana, and continued to evolve separately.
+Today the South American and Australian groups are about as different as humans and mice, Belov says.
+Belov says birds and other non-mammals have a relatively simple MHC whereas in placental mammals it is much more complex.
+"Marsupial MHC turns out be intermediate," she says.
+This suggests that "there's been some major changes [in the human immune system] that have gone on quite recently and they're probably more recent than a lot of people expected".
+Comparing marsupials
+A project to sequence the genome of Australia's tammar wallaby, being done jointly by the Australian Genome Research Facility and the Human Genome Sequencing Center in the US will complement work on the opossum, says Belov.
+Belov also has an Australian Research Council grant to study the MHC in the tammar wallaby.
+"If we have the tammar wallaby sequence and the opossum sequence we can pretty much predict the sequences of all the other marsupials", she says.
+
+This person of European descent is most likely to have wet, gooey earwax. Now scientists know why
+Geneticists say they know why people from some parts of the world have wet, gooey earwax and others have the dry, flaky stuff.
+They describe online today in the journal Nature Genetics how a single gene controls its consistency.
+Human earwax is a secretion that traps insects, cleans the ear and prevents the outer parts of the auditory canal from drying out.
+But cerumen, to give it its scientific name, has long puzzled researchers, who have debated why different populations have a different consistency.
+For example, dry earwax is more common in people from China and other countries in eastern Asia. And people of European or African descent are more likely to have the wet variety.
+Dr Koh-ichiro Yoshiura, from Nagasaki University and colleagues say mutations in a single gene hold the key.
+By looking at Japanese people with different types of earwax, they identified the gene ABCC11, which codes for a type of cell channel.
+This channel acts as a kind of gate to control the flow of molecules, which in turn determines wax type.
+A mutation in this gene alters the channel's structure and reduces its activity, affecting the wax consistency.
+People who inherit two copies of the mutant gene, one from each parent, have dry earwax. Any other combination gives you goo.
+The authors compared the gene with earwax genes from 33 different populations around the world, plotting a time-map of where and when the gene mutated.
+They conclude that the change in the channel type first occurred in northeast Asia, a change that then spread throughout Asia, and to Native American and Inuit populations with Asian origins.
+
+Facial tumour disease can leave the face of Australia's carnivorous marsupial looking "like pizza", researcher Anne-Maree Pearse says
+The mysterious facial tumour disease ripping through Australia's Tasmanian devil population may be an infectious cancer spread by biting, a researcher says.
+Anne-Maree Pearse of Tasmania's Department of Primary Industries, Water and Environment reports in the journal Nature today that the tumour cells are chromosomally identical despite being found in different animals, suggesting the existence of a "rogue cell line".
+"The thrust of my theory is that a cell line developed in a cancer in a devil somewhere, some time," she says.
+"This cell line became persistent and basically had an existence of its own ... and is just passing through the population like an epidemic."
+Pearse says during fights mutated tumour cells may break away from the ulcerated tumour of a diseased devil and become "transplanted" into a healthy devil, where they form the seed of a new tumour.
+"We propose that the disease is transmitted by allograft, whereby an infectious cell line is passed directly between the animals through bites they inflict on one another," she writes.
+Facial tumour disease, which first became apparent in the mid 1990s, is now present across more than half of the southern island state and has cut the Tasmanian devil (Sarcophilus harrisii) population in some parts by up to 80%, according to the Tasmanian government.
+Genetic bottlenecks
+Pearse says devils may be particularly susceptible to the disease because of genetic bottlenecks caused by past population crashes.
+The crashes resulted in a loss of genetic diversity, which may have caused a net weakening of the devil's immune defences, she says.
+Her colleague Dr Menna Jones, a conservation biologist from the University of Tasmania, says the cell line transmission theory is backed by her own research, done with Rodrigo Hamede, into devil fighting and biting behaviour.
+"Given what we know about the ecology and behaviour of devils, if you're going to pick any species that might transmit any pathogen or disease by biting, devils would be a very likely candidate," Jones says.
+The theory comes as good news for those involved in combating the disease, she says.
+"What's nice about the allograph theory is that it does make disease suppression or disease control simpler," she says.
+"If transmission is simply transfer of tumour cells from devil to devil  ... the most effective thing you can do is simply to take sick animals out of the population." 
+Jones says the research comes as the Tasmanian government prepares to launch a two-year disease suppression study in the state's southeast following a successful pilot last year.
+The study will monitor the impact of isolating an estimated 300-400 devils that live on Tasmania's Forestier and Tasman peninsulas, where the disease hasn't yet established a stronghold. They will be separated from the mainland with devil-proof grates.
+Can it spread to humans?
+Pearse, who also has a background in human cytogenetics, says studying devil facial tumour will advance understanding of cancer in humans.
+She says there's no human equivalent of a transmissible cancer but there have been cases where organ transplant patients have developed cancer if cells were hidden in the donor organ.
+She says it's highly unlikely devil facial tumour disease could spread to other species, including humans, but this will be the subject of future research.
+
+This old spacesuit will be tossed out of the International Space Station at the weekend to become a cheap, home-spun satellite. It'll transmit messages back to Earth until its batteries die out, then become space junk
+Three Russian spacesuits are being prepared for a spacewalk at the weekend from the International Space Station, but only two will be coming back inside when the planned six-hour excursion is over. 
+There's no mutiny in the works, though it would be easy to think so after watching what station commander Bill McArthur and flight engineer Valery Tokarev have in mind.
+They'll be tossing the third suit overboard. 
+No one will be inside the free-flying suit. Rather, it is stuffed with old clothes, batteries and a couple of electronics boxes. An antenna is fixed to the suit's helmet.
+Then it becomes a free-flying satellite in orbit around Earth until its batteries die and it becomes orbiting space junk.
+Because its orbit is relatively low, it will be pulled back into Earth's atmosphere within a few weeks or months and be incinerated.
+The being does have a name, SuitSat, and a message, though you will need an antenna and radio receiver to hear it.
+Run by amateurs
+SuitSat is an innovative, budget-free, volunteer effort of an international amateur radio organisation.
+It's equipped with a series of messages that last 30 seconds and a picture that will be continuously transmitted for as long as its batteries hold out. 
+"The idea was brought up at [an amateur radio] symposium in October 2004," says amateur radio operator Lou McFaden of Orlando.
+"At the time we had started figuring out [a project] that we could do that was low enough in power. A Russian representative brought up that [Russian space officials] had been trying to find something more useful for these old suits they had on the station." 
+Just in time
+The project quickly gained momentum, but time was short. With donated equipment and volunteer time, SuitSat was pulled together in a matter of weeks, delivered to NASA, transported to Russia and launched aboard a cargo ship that arrived in September 2005. 
+Its mission is set to begin at the weekend. Thousands of amateur radio buffs are expected to try to pick up SuitSat's transmission during its relatively short lifetime.
+The suit's batteries likely will last only a few days, says McFaden, who built the hardware. 
+SuitSat also contains a CD with hundreds of pictures, artwork, poems and signatures of students worldwide. 
+Project organisers already have their eyes on another Russian spacesuit expected to be decommissioned later this year or in 2007. 
+"We're hoping to be able to do it again," says McFadin. "We already decided some things we want to do on the next one if we get the chance." 
+Tuning in
+SuitSat's signal will be transmitted on 145.990 MHz FM. 
+"All you need is an antenna, the bigger the better, and a radio receiver that you can tune to 145.990 MHz FM," says Frank Bauer with NASA's Goddard Space Flight Center. "A police band scanner or a hand-talkie ham radio would work just fine." 
+A log of people who have made contact will be available on the SuitSat website.
+SuitSat is an outgrowth of the amateur radio project already operating aboard the space station, Amateur Radio on International Space Station, or ARISS.
+
+The latest computer virus, which arrives by email, is ready to delete your files this Friday
+A destructive worm posing as a pornographic email may already have infected hundreds of thousands of computers and could erase many everyday files on 3 February, security experts warn. 
+The Kama Sutra worm, which targets Microsoft, Adobe and ZIP files, is a threat because many users will not know the virus has infected their computers until it is too late, security experts say. 
+They also estimate that the worm, which spreads by emailing itself to addresses in an infected computer's mailbox, may already have slipped onto 275,000 to 500,000 machines and is now simply waiting to obliterate files on Friday.
+The virus, also known as Grew.A or MyWife, tricks users by appearing as an email attachment with subject lines such as Hot Movie, give me a kiss and Miss Lebanon 2006.
+Some variations refer to the ancient Kama Sutra guide to elaborate sexual positions to attract attention and convince victims to open the email. 
+"It claims to be a movie or picture with some sort of sexual content," says Johannes Ullrich, chief research officer at the nonprofit SANS Institute research group. "That is how it tricks you." 
+The virus causes a keyboard and mouse to freeze. It then disables anti-virus programs when the computer is restarted, leaving a machine vulnerable, says Ken Dunham, rapid response director at VeriSign Corp's  security unit iDefense. 
+The virus mainly has infected computers of vulnerable consumers and small businesses, which are far less likely to have up-to-date security software, he says. 
+The Kama Sutra worm also stands out because its primary purpose is to destroy files rather than to seek financial gain or to take control of a computer, security experts say. 
+Dunham says any users who suspect they may have triggered the worm should reinstall an anti-virus program and make sure the virus has been removed. 
+"It is already under way and will be activated unless people get removal tools," he says. "If you have opened an email and your computer froze up, you should be very concerned."
+
+Humans may have domesticated dogs much more recently than DNA studies suggest
+One of the most extensive surveys of the earliest known dog burials suggests humans domesticated canines much later than other studies show.
+The survey, which suggests domestication occurred between 13,000 and 17,000 years ago, counters some earlier theories based on gene changes that distinguish dogs from their wild wolf counterparts.
+A few of those theories held that domestication occurred anywhere between 40,000 and 135,000 years ago, much earlier than the new study suggests.
+The new study, published in the February issue of the Journal of Archaeological Science, suggests that the bond between humans and dogs coincides with canine burials. 
+The earliest known morphological evidence of what was probabably dog remains dates to around 17,000 years ago in central Russia.
+But the practice of burying dogs appears to have begun between 14,000 and 15,000 years ago. Burying dogs then became more common around 12,000 years ago.
+"[This] was a time of major population expansion, starting with, for our purposes, colonisation for the first time of eastern Eurasia and finally on into the New World," says author Darcy Morey, an assistant professor in archaeology from the University of Kansas.
+"This is just me being mushy and fuzzy, but it seems that folks were a little more willing to try things, like drift into previously unoccupied expanses, and maybe engage in human-animal associations that resulted in domestication." 
+Morey believes the canine genetic break from wolves may not be linked to domestication. 
+"Quite simply, if the dog and wolf genomes really did separate as long ago as some molecular studies have suggested, or even in that vicinity, the animals that were destined to become dogs must have made their living for some time essentially in the old-fashioned way, like wolves," he says. 
+An evolving relationship
+The burials reveal our evolving relationship with dogs. Often dog skeletons lay alongside human ones. 
+In one 7000-year-old Swedish grave, archaeologists found the remains of a dog stretched out on the legs of a deceased man, as though the man hoped to hold and pet his canine friend for eternity. 
+The dog's neck was broken, indicating that it had been killed when its owner died. 
+Dogs buried without humans in North and Central America still show a loving touch and possibly a ritualised internment.
+A grave found in what is now Rhode Island, for example, contains a prehistoric dog that was arranged to lie on its left side with its front paw under its head. 
+Sign of the times
+The age and condition of the dogs when they died also reveal domestication and the bond with humans, according to Morey.
+He describes a Middle Archaic burial dating from 6700 to 7180 years ago that was found in what is now Tennessee. The male dog discovered in the grave was "unusually old". 
+Its skeleton indicates the animal suffered from traumatic injuries, arthritis, a persistent infection, and broken bones, some of which had healed, and some that had not. 
+"The pathological condition of this individual suggests that the owner insured the safety and well-being of the individual throughout its life since it is doubtful that, given all the traumatic and age degenerative manifestations, the dog could have survived in the absence of care," Morey explains. 
+More evidence
+Christyann Darwent, an assistant professor of anthropology at the University of California at Davis, says she agrees with Morey's time window for dog domestication. 
+"Dogs and humans could have been hanging out together long before 17,000 years ago, but domestication means we were manipulating their breeding, and that probably didn't happen until more recently," she says.
+"The burials represent some of the best evidence we have for the strong social ties that exist between dogs and humans." 
+Darwent says domestication has benefited dogs and humans, but she suggests humans should take responsibility for their alteration of canines over the millennia. 
+"Some dogs, such as my own pet, are so reliant on humans that they could never fend for themselves in the wild," she says.
+"We must remember that we have manipulated them so much with domestication that they often must depend upon us now for their survival."
+
+Moroccan runner Hicham El Guerrouj's world record will be left in the dust one day, according to a mathematical analysis of times for the men's one mile race
+Athletes could run the mile 18 seconds faster than the current record, according to an Australian mathematician who's gone back over the past hundred years of records.
+Dr Michael Deakin of Melbourne's Monash University  first calculated the absolute limit for the distance 40 years ago when he declared it to be 3 minutes 32 seconds.
+He will tell a meeting of the Australian and New Zealand Industrial and Applied Mathematics group later today that he has since revised the data.
+He now says athletes could run the mile in 3 minutes 25 seconds, much faster than the existing record of 3 minutes 43 seconds set by Morocco's Hicham El Guerrouj in 1999.
+Deakin says more sophisticated computing technology and more records led him to revisit his earlier work.
+"The reason for revisiting [my original study] is twofold," he says.
+"There's a much bigger data set than there used to be and secondly you've got all sorts of computational tools you didn't back then.
+"So I thought I'd give it another run for its money."
+He didn't make any estimate of when, if ever, this new height in athletic performance would be scaled.
+Deakin arrived at the figure using non-linear trend analysis, a branch of statistics commonly used in economic forecasting. 
+"I plot the different records ... and then I drive a trend curve through it ...which cuts out all the ups and downs," he says.
+"The idea of the trend curve is to have a line at the top which more or less always will be achieved, and a line at the bottom which is never to be achieved."
+In the past he's also used the method to estimate calcium in the bodies of dialysis patients and the trajectory of arrows as described in a passage of Ancient Roman poetry.
+A three minute mile?
+The mile, the equivalent of 1609 metres, has been replaced by the 1500 metres but is still common in some countries.
+And although international athletics bodies now only recognise world records for metric distances, they have made an exception for the mile and still keep records today.
+The mile was once famed for the 4 minute barrier which, was thought to be impossible until Englishman Roger Bannister's time of a little over 3 minutes 59 seconds in 1954.
+Speculation has now shifted to the 3 minute barrier, although most experts agree that athletes are unlikely to meet this without some sort of assistance.
+Dr Shane Brun, a senior lecturer in medicine at James Cook University and vice-president of Sports Doctors Australia, says it's almost impossible to predict the bounds of athletic performance.
+But humans will reach a stage where they simply can't get any better without some form of modification, he says.
+"Whether that's through evolution or science or drugs we just don't know," he says.
+
+New measurements of planet 2003 UB313, dubbed Xena, show its diameter is about 700 kilometres larger than Pluto's. So will UB313 be named the solar system's 10th planet?
+Xena, the possible 10th planet in our solar system, is even larger then Pluto, research shows.
+Astronomers led by Professor Frank Bertoldi of Germany's University of Bonn publish their findings today in the journal Nature.
+They say they have measured reflected solar radiation from Xena, or 2003 UB313 to give it its official name, using a 30 metre telescope in Spain.
+The result: UB313 has a diameter of about 3000 kilometers, about 700 kilometres larger than Pluto's.
+This would make UB313 the largest solar system object to be spotted since the discovery of Neptune in 1846.
+Astronomers have been debating the status of UB313 ever since the announcement last year that it had been discovered 15 billion kilometres from Earth.
+Pluto's defenders blasted it, saying it was not a planet ... but a vulgar rock.
+Astronomers get abusive
+The polite term for such abuse is a KBO, Kuiper Belt Object, for the estimated 100,000 pieces of icy, primeval debris that slowly encircle the Sun on the outskirts of the solar system, far beyond the orbit of Neptune. 
+The UB313 supporters' club responded tartly, claiming that if anything deserved the moniker of KBO, it was Pluto. 
+For one thing, Pluto, discovered in 1930 by American Clyde Tombaugh, has a weird, unplanetary orbital plane. It is a whole 17&deg; off the horizontal plane taken by the eight other planets. 
+Its path around the Sun is also so egg-shaped that for 20 years of its 248-year orbit it's inside the track of Neptune itself. 
+Now, weighing powerfully in this group's favour, are the first detailed measurements of UB313's size. 
+If the data is accepted by a special 19-member panel set up by the International Astronomical Union to determine what constitutes a planet, Pluto faces being booted out of the solar system's elite club, and downgraded to a mere KBO. 
+Either that, or the planetary list will have to expand to include UB313 and possibly many others. 
+Time's running out
+For Bertoldi, time is running out for Pluto as the solar system's outermost planet.
+"Since UB313 is decidedly larger than Pluto, it is now increasingly hard to justify calling Pluto a planet if UB313 is not also given this status," he says.
+Pluto's humiliation is knowledge's gain, though.
+"The discovery of a solar system object larger than Pluto is very exciting," says Dr Wilhelm Altenhoff of the Max Planck Institute for Radio Astronomy, a veteran watcher of asteroids and comets.
+"It tells us that Pluto, which should properly also be counted to the Kuiper Belt, is not such an unusual object. Maybe we can find even other small planets out there, which could teach us more about how the solar system formed and evolved.
+"The Kuiper Belt objects are the debris from its formation, an archaeological site containing pristine remnants of the solar nebula from which the Sun and the planets formed." 
+UB313 has yet to be given an official name.
+Professor Michael Brown, the California Institute of Technology astronomer who led the team that discovered UB313, informally calls it Xena after the warrior princess of TV fame.
+But if the object is confirmed as a planet, he will be under pressure to name it, like the nine others, after a figure from Greek or Roman mythology.
+In a naming competition run by the magazine New Scientist, readers' suggestions included Persephone, Pax, Galileo and Cerberus, as well as Rupert and Bob.
+Last October, Brown and his team announced that Xena had a moon called Gabrielle, named after the on-screen warrior's travelling companion.
+
+Pigeons will soon be equipped with a mobile phone to text their air pollution reports back to us on the ground
+A flock of pigeons will monitor the sky for pollution then beam back their findings to a special pigeon blog, scientists say.
+The 20 pigeons will carry a GPS satellite tracking receiver, air pollution sensors and a basic mobile phone, according to a report in New Scientist magazine.
+The phone will allow text messages on air quality to be beamed back in real time to a website.
+Miniature cameras slung around the pigeons' necks will also post aerial pictures.
+The idea is the brainchild of researcher Beatriz da Costa, an assistant professor at the University of California at Irvine, and two of her students.
+They have built a prototype of the pigeons' equipment, containing a mobile phone circuit board with SIM card and communication chips, a GPS receiver, and sensors capable of detecting carbon monoxide and nitrogen dioxide. 
+"We are combining an air pollution sensor with a homemade [mobilephone]," da Costa told New Scientist.
+The team is planning to squeeze all the components onto a single board small enough for the birds to carry in a backpack, the report says. 
+The pigeons will take to the air at the Inter-Society for Electronic Arts annual symposium in San Jose in August. 
+The data they send back will be displayed on the blog in the form of an interactive map.
+
+Adding an immune system booster to diluted vaccines may mean a little vaccine goes a long way
+Much smaller doses of vaccines may be needed to combat outbreaks of bird flu, tuberculosis and SARS than once thought, Canadian research shows.
+The research by a team at the University of British Columbia could mean more shots will be available. 
+The team led by Professor Wilfred Jefferies says standard doses can be reduced 100-fold and still be safe by adding an immune system booster commonly found in the human body. 
+The study shows that when the immune system booster is added at low doses to vaccines and injected into mice exposed to rabies, measles and smallpox, an immune response kicks in to protect them from infection. 
+The so-called TAP molecules deliver peptides inside cells from the body's immune system or vaccines.
+If this transporter is switched off, as in cancerous cells, disease fighters cannot be moved where they need to go within the cell to do their job. 
+The results of the seven-year study were published in a recent issue of the journal PLoS Pathogens. 
+"This new paradigm is shown to be applicable to many viruses, including poxviruses, and could significantly advance the creation of new vaccines and improve those that already exist," the scientists say.
+This could prove especially important if the H5N1 bird flu, expected by many to be the next worldwide pandemic, begins to pass between humans. 
+What happens in a bird flu outbreak?
+Bird flu has killed some 85 people since emerging in Asia in 2003. Experts say it could kill millions if it mutates into a form easily passed between humans.
+It could take up to six months to develop a vaccine should human-to-human transmission occur. With smaller dose sizes, a hundred times more vaccine shots could be made within the same period of time. 
+"We're hoping it will be incorporated into a number of different vaccines," says Jefferies. "It's powerful because we think it can make general vaccines much better." 
+Smaller doses will also make some vaccines, including that for smallpox and anthrax, less toxic and therefore better tolerated by those with weaker immune systems, Jefferies says. 
+HIV patients, in particular, could benefit, as well as up to an estimated 20% of the population who react badly to vaccines.
+"Some pathogens don't currently have effective vaccines," says co-author Timothy Vitalis. "I hope the technology can be used to solve some of the needs in controlling infectious diseases." 
+How do you boost a vaccine?
+Jefferies first imagined the possibility of this application for vaccines after noticing that TAP is turned off in cancer cells, meaning that the body's natural immune defense does not recognise that it needs to attack these cells.
+He found that when TAP was added to the cancerous cells the immune system suddenly 'switched on' and fought back. 
+"TAP is a key molecule in the creation of immune responses," says Jefferies. "This molecule fought viruses when it was found in normal amounts in the cell. I thought, 'If a little bit is good, is a lot [of TAP] even better?" 
+Researchers say they are not sure why the TAP molecules are turned off in cancer cells, but hope further study may eventually lead to a new cancer treatment too. But that is still years away. 
+Jefferies says the team is currently trying the method out with prototype vaccines that could lead to clinical trials in the next two years, depending on funding. 
+The research was primarily funded by the Canadian Institutes of Health Research.
+
+This image shows the flash of light emitted when the Deep Impact probe smashed into the comet. The comet nucleus is in blue and maroon, and the impact flash is ringed in multiple colours
+Ice has been detected on the nucleus, or solid body, of a comet for the first time, researchers report.
+They say that Comet Tempel 1, the target of NASA's Deep Impact space probe, has three patches of ice on its surface.
+But most of the frozen water probably lurks deeper inside.
+Co-investigator Dr Jessica Sunshine and colleagues report their findings online today in the journal Science. 
+The surface ice was detected by instruments on board the probe before it crashed into the comet in July last year.
+Cameras spotted several patches bluer than surrounding areas. And infrared spectroscopy confirmed these patches were water ice.
+The scientists suspect the ice is in large grains, probably aggregates. And the deposits are impure, with only a small fraction being water ice, the rest consisting of dust.
+The surface deposits are also not enough to account for the water vapor in the cloud of gas and dust that surrounds the comet's nucleus, the scientists say.
+"These new findings are significant because they show that our technique is effective in finding ice when it is on the surface," says Professor Michael A'Hearn of the University of Maryland, the project's principal investigator. 
+"We can [also] therefore firmly conclude that most of the water vapor that escapes from comets is contained in ice particles found below the surface." 
+Into the heart of a comet
+Deep Impact slammed into the comet last year aiming to collect data about the comet's heart. 
+Comets are of particular interest because they are believed to be made up of the leftover debris from the gas, dust, rocks and ice that formed the outer planets in our solar system some 4.6 billion years ago. 
+Scientists have long known that comets contain substantial amounts of ice. But before Deep Impact, they did not know how ice was distributed throughout the comet's nucleus. 
+Some astronomers believe comets 'seeded' Earth with some of the water and carbon-based molecules that make up living things.
+
+Neanderthals used their knowledge of animal behaviour to hunt mountain goats like these Caucasian turs, just like early humans did
+Neanderthals did not disappear because modern humans were better hunters and thus out-competed them for resources, say US and Israeli anthropologists.
+On the contrary, they were top predators who knew how to hunt the biggest and fastest of the animals. 
+Neanderthals went extinct about 30,000 years ago, after having inhabited Europe and parts of Asia for roughly 200,000 years.
+The reason for their demise has been long debated and frequently attributed to modern humans' greater intelligence and consequently greater hunting skills. 
+But evidence from animal remains hunted by Neanderthals clearly indicates these hominids were as good as any early modern humans at hunting, report Daniel Adler, an assistant professor and palaeoanthropologist at the University of Connecticut, and colleagues in the February issue of the journal Current Anthropology. 
+The researchers examined abundant faunal remains, in particular thousands of bones belonging to a mountain goat species called the Caucasian tur that still exists today. 
+The trove was excavated at Ortvale Klde, a rock shelter in the southern Caucasus in the Republic of Georgia dated to between 60,000 and 20,000 years ago. 
+Evidence of killing
+There was no doubt that the animals were hunted and killed. Indeed, the bones featured cut marks from human butchering and fragmentations typical of marrow consumption, showing that meat processing behaviours were not significantly different between Neanderthals and modern humans. 
+"Given the abundance of animals, one might think that Neanderthals would kill as many animals as possible, regardless of age, and therefore nutritional returns," says Adler. 
+But analysis of tooth wear revealed that two-thirds of the animals were animals of prime age, the strongest, fastest, most nutritious and most difficult to capture members of the herd. 
+"Neanderthals, like the modern humans that followed them, were quite savvy, choosing instead to maximise their dietary intake per energy expended by hunting prime age adults. 
+"Given the species involved and the rough terrain, this would require sophisticated hunting tactics, [and] knowledge of animal behaviour, in particular migration routes and flight behaviour, and group cooperation," Adler says. 
+Expert timing
+Neanderthals timed their hunts for late autumn to early spring, during the Caucasian tur's seasonal migration to lower elevations, where the site of Ortvale Klde is located. 
+"They maintained an intimate relationship with their environment and were capable of understanding exactly where and when particular resources could be found in abundance," Adler says. 
+Archaeologist John Shea, an associate professor at Stony Brook University says:
+"The study is excellent, precisely what is needed: a comparison of how Neanderthals and modern humans used the same landscape close enough in time so that any differences discovered reflect behavioural differences and not environmental ones." 
+Still a mystery
+Shea believes that multiple factors, varying from region to region, may have played a role in the disappearance of Neanderthals. 
+"The simple answer to the question of why Neanderthals became extinct is 'nobody knows'. But studies like this one certainly move us a lot closer to being able to make more clearly testable hypotheses," he says.
+"Now the hypothesis that Neanderthals became extinct because they were ineffective hunters is in deep trouble."
+
+A book at bedtime doesn't guarantee children become better readers in the long run, researchers say. Their genes play a bigger role
+Genes, rather than reading to young children at home, have a greater influence on how they learn to read once they reach school, researchers say.
+The study, published in the latest issue of the Journal of Research in Reading, is the first to demonstrate the influence of genes on potential reading ability in children younger than six.
+The study of pre-school age twins from Australia, the US, Norway and Sweden followed into their early school years, found genetic variability accounted for most of the differences in skills that predicted later reading ability.
+These skills included understanding the sounds in words, familiarity with letters and verbal fluency.
+Australian researcher Brian Byrne, professor of psychology from the University of New England in Armidale, stresses that the amount of time carers spend reading to children at home is important.
+But the research shows the significance of supporting pre-school age children who are having difficulties with letters and words.
+"If a child is reading poorly in part because they are not as genetically well-endowed as other children, we know we will need to work harder and devote more resources to get them up to scratch," says Byrne.
+By the end of their second year at school, the Australian children in the study show almost no trace of the influence of their home environment on reading ability, he says.
+And the influence of genetic variability actually increases as children get older, he adds.
+"We don't know which genes are involved but some of the genes in question affect brain development, maybe even embryonically. My guess is that in about five years, we will have identified a suite of actual genes that are driving this."
+Identifying children with problems
+Byrne says the study highlights the importance of identifying children much earlier who might develop reading disorders, especially dyslexia.
+"There is evidence that early and focused intervention for potential reading disorders in children with family histories of dyslexia can lead to grade-level performance in the early school years," he says.
+"Our findings should act as a spur to continued research, to adoption of the best evidence-based teaching practices and to early identification of children at risk for reading disability."
+
+DNA evidence has questioned the quality of &#214;tzi's sperm, which may have affected his standing in Stone Age society
+A Stone Age man found frozen in the Alps some 5300 years after he was murdered under mysterious circumstances may have been a childless social outcast, a new study shows. 
+Italian anthropologist Dr Franco Rollo, from the University of Camerino, studied fragments of the DNA belonging to &#214;tzi, as the mummy has become known.
+Rollo and his colleagues describe in the American Journal of Physical Anthropology how he found two typical mutations common among men with reduced sperm mobility.
+A high percentage of men with such a condition are sterile, according to the museum that stores &#214;tzi the iceman.
+"Insofar as the 'iceman' was found to possess both mutations, the possibility that he was unable to father offspring cannot be eliminated," says the South Tyrol Museum of Archaeology in the Alpine town of Bolzano.
+"This not improbable hypothesis raises new questions concerning his social rank within his society," it adds, arguing that the new evidence supports a theory that views the man as a social outcast. 
+Hikers discovered &#214;tzi in the mountains between Italy and Austria in 1991. 
+In 2001, scientists found an arrowhead in the iceman's shoulder blade, and tests revealed blood from four different people on his clothes and a cut in his hand, possibly from a fight. 
+Medicine in the man's pockets and sophisticated weapons seemed to indicate that he was a shaman or a chieftain.
+One theory says &#214;tzi was the victim of a power struggle in his own tribe. A rival theory proposes the opposite, that he was a reject. 
+Rollo and his colleagues were also able to assign the mummy's DNA to one of the basic groups of human DNA historically occurring in Europe. 
+His basic DNA resembles that of the Ladines, an ethnic group still living in the region today, and that of residents of the &#214;tztal valley where he was found, the museum says.
+
+The discovery of plant viruses in human faeces raises questions about the safety of human waste as fertiliser
+Faeces from healthy humans contains live viruses, most of which are plant viruses that could sicken and deform plants, an international study shows.
+The finding, published in the current issue of the journal PloS Biology, could have implications for the use of human waste as fertiliser.
+Collected water, otherwise known as reclaimed or grey water, may also contain deadly plant viruses.
+But future studies are needed to determine if such water, which is sometimes used for irrigation, can infect plants. 
+The researchers say the viruses we pass probably do not harm us and airborne transmission is unlikely.
+Instead, the viruses probably hitch a ride through the human body via food, even when the food is cooked or dried. 
+"The fact that we could detect plant viruses in mixtures of foods consumed by the [study] donors suggests that the plant viruses found in human faeces originate from our food," says Mya Breitbart, one of the study's authors, a San Diego State University biologist. 
+"For example, PMMV [pepper mild mottle virus] was detected in processed chilli sauces and chilli powder, but not in fresh peppers. 
+PMMV survives processing of foods and passage through the human gut, and the viral particles are known to be extremely stable," she adds.
+"There is no evidence that people should try to avoid getting this virus. It most likely has no adverse effects on human health."
+Plants are not so lucky. Peppers infected with this virus can experience stunted growth and sunken brown spots that look like rot on the fruit.
+The researchers found the pepper virus in 14 of 20 human faeces samples collected from healthy individuals in California and Singapore.
+The virus might even multiply in the human gut, the researchers say, as the amount in the faeces was more than the virus load measured in food. 
+The scientists analysed in detail the faeces from two of the test subjects, who came from San Diego, and were able to identify 36,769 RNA virus sequences representing 35 known plant viruses, two animal viruses, one yeast virus and four bacteria. 
+One of the animal viruses is linked to diarrhoea, while the other, Moloney murine leukaemia virus, has been linked to cancer in humans and animals.
+Some 24 of the identified plant viruses are known to harm consumable crops, including fruits, vegetables, tobaccos and cereals. 
+"I am not aware of any cases where a plant virus has mutated into a virus that caused harm to humans. However, it is important to understand and characterise the viruses that are present in the guts of healthy humans in order to understand what is happening in the case of disease," Breitbart says.
+"For example, if we want to look at the viruses associated with gastrointestinal problems, we will need a baseline to compare against." 
+She even thinks humans might someday benefit from plant viruses, since scientists might be able to deliver medications for diarrhoea and other intestinal disorders using the viruses, now that it is known the viruses survive the acidic, arduous journey through our bodies. 
+Surprised
+David Relman, associate professor of microbiology, immunology and medicine at Stanford University, says is "surprised to see a plant virus dominate in terms of relative abundance to such an extent". 
+"One might then wonder whether this is simply a relatively unique finding to one or few individuals with a specific dietary proclivity. But these investigators show that the findings are relevant to a diverse group of humans." 
+He does not think the findings are worrisome. 
+"It is probably the case that these viruses have been with us for some time," Relman says.
+
+A waiting room questionnaire will make it easier for doctors to spot people anxious about their health, but with no physical symptoms, psychologists say
+One in 16 Australian patients suffers from imaginary ills, the country's first study into the prevalence of hypochondria reveals. 
+The research by psychologist Dr John Franklin of Macquarie University and colleagues, which will be submitted for publication, looked at 1381 patients who attended 13 family doctor surgeries across the state of New South Wales.
+It found 6.2% of the population presented with a primary diagnosis of hypochondriasis.
+"That's quite high," Franklin says.
+It is generally estimated that only a third of patients who visit a general practitioner have a condition that is purely physical.
+"At least a half, but variously estimated at about two-thirds, have a condition that's in some part the result of social or psychological factors," Franklin says.
+"Roughly a third of the total patients actually have what you might call a psychosomatic condition, which is something that has a physical manifestation but has really got an underlying psychological cause."
+Health anxiety
+Franklin and his team went further to specifically investigate hypochondriasis, a condition where a person believes they have a serious illness in the absence of confirming physical evidence.
+"This is more than just a psychosomatic condition. It's a condition where the patient actually believes that they have something seriously wrong with themselves," Franklin says.
+Patients with hypochondriasis, or health anxiety as psychologists prefer to describe it, usually complain of physical symptoms, but these tend to be vague and non-specific.
+The patients in the study were assessed using a questionnaire devised by Franklin and his colleagues called the Health Anxiety Interview Schedule.
+Franklin says the form was designed as an alternative to the current international standard, the Whiteley Index, which he says isn't specific enough and doesn't link into the Diagnostic and Statistical Manual of Mental Disorders criteria for hypochondriasis.
+A new test
+The new test is described in the current Journal of Psychosomatic Research.
+Franklin says it is more targeted, more streamlined and designed to be filled out by patients in the general practitioner's waiting room.
+"The score they get can alert the GP to the possibility that there are social or psychological issues that might be going on," he says.
+Questions relate to symptoms, physical signs, what the patient thinks is wrong, how long they've had concerns, whether they have found previous explanations reassuring and whether other doctors are seeing them.
+On average, patients who fell into the health anxiety category were seeing between three and four doctors, the research found.
+Franklin says it's important to identify patients with health anxiety because, along with children in the first year of life and people in their last, this group uses the lion's share of health resources.
+
+Mmm, definitely rage. Computers are learning to recognise your emotions and soothe your stress
+Wouldn't it be great if your computer could recognise when you're frustrated with it and adjust itself to calm you down? Emotion-sensing technology could someday allow a computer to do just that, researchers say. 
+Computer scientist Christian Peter of Germany's Fraunhofer Institute for Computer Graphics and his colleagues are working on a system that collects data about a person's emotional state using sight, sound and touch technology. 
+The system then interprets the information and reacts accordingly. 
+For example, if a computer senses that its user is agitated, it might tone down the background colour of the screen, turn down background music, enlarge or reduce graphics, adjust the flow of information being presented to the user or simply apologise. 
+"With humans, somebody who ignores the feelings of others is not liked as much as somebody who shows some sort of emotional feedback. Why should it be different with computers?" says Peter.
+But sensing emotions from a person is not always easy. 
+Current methods for collecting the data require researchers to wire users with electrodes and monitor their behaviour in a laboratory. 
+Less-obtrusive means, such as using a video to monitor gestures or a recorder to analyse voice, allow the user to behave more naturally. But the data can break down if the person moves too far away. 
+Tuning in to your emotions
+Peter and his team are working on technology that unobtrusively senses a person's emotions while they interact freely with a computer.
+Their latest prototype is a wireless electronic glove that measures heart rate, blood pressure and skin temperature. 
+Peter will be demonstrating the wireless glove at the CeBIT exhibition in Hanover, Germany, in March. 
+"Fraunhofer has been on the leading of edge of innovating," says computer scientist Professor Rosalind Picard of the Massachusetts Institute of Technology.
+Information gathered by the glove is transmitted wirelessly to a base unit, which stores it on a memory card or sends it to a computer database.
+Software written by Peter's team analyses the data and retrieves patterns that indicate certain emotions. 
+Is that anger I'm sensing?
+For example, if a person's heart rate increases quickly and their skin temperature falls below a certain threshold, it may indicate that they are angry.
+A different combination of other variables suggests the person is slightly surprised or very surprised. 
+The Fraunhofer team is also working on technology that will read facial features using an ordinary webcam.
+The goal is to collect all the emotion-indicating information in one database, analyse it in real time and program the computer to respond immediately.
+
+Stem cell lines derived from abnormal embryos can improve our knowledge of genetic diseases, researchers say
+Australian researchers are seeking the country's first licences to make stem cell lines from freshly created human embryos with genetic abnormalities.
+This is a shift from the current situation where all research in Australia on human embryos has been confined to frozen spare embryos created during previous in-vitro fertilisation (IVF) treatment.
+The medical director of Sydney IVF, Dr Robert Jansen, says the group has applied to the National Health and Medical Research Council's licensing committee for two licences for fresh embryos.
+One relates to embryos created during IVF, but having genetic diseases like Huntington's, cystic fibrosis and muscular dystrophy.
+The second licence is for IVF embryos that have failed to develop properly and contain chromosomal abnormalities or mutations.
+"Both the new licences are [to] intentionally produce abnormal stem cell lines so that they can be used for research into the relevant diseases," Jansen says.
+Dr David Cram of Monash IVF and his colleague, stem cell pioneer Professor Alan Trounson, are also seeking access to embryos with genetic diseases.
+"We are going through a process at the moment to gain approval for using embryos that are being found to be affected by genetic disease for creating stem cell lines," Cram says.
+"The whole idea is that we believe that these stem cell lines will be useful in ultimately identifying new treatments for patients ... to identify a potential drug to change the abnormality."
+Fresh or frozen?
+The use of fresh embryos was addressed by the stem cell and cloning Legislation Review Committee, which handed down its report last December about changes to current stem cell research laws.
+The Lockhart report recommends that "fresh ART [assisted reproductive technology] embryos that are diagnosed by pre-implantation genetic diagnosis ... as being unsuitable for implantation should be permitted to be used, under licence, for research, training and improvements in clinical practice".
+Cram says legislative changes will be required before researchers can have access to fresh, as opposed to frozen embryos.
+However, Jansen says the restrictions on using fresh embryos are not enshrined in law, but are only a "suggestion" of the Australian Health Ethics Committee, which stipulates a two-week waiting period before a couple commits an embryo to research.
+The timeframe effectively rules out the use of fresh embryos, which would be too old to use for stem cells after two weeks.
+Pre-implantation genetic diagnosis
+The abnormal embryos the researchers are seeking will be the products of pre-implantation genetic diagnosis (PIGD), which allows scientists to detect abnormalities in a blastocyst before it's implanted in the womb.
+In a paper published in the journal Endocrine Reviews, Trounson reviews the use of chromosomally abnormal or mutant human embryos from IVF clinics using PIGD.
+"These ... lines are an important resource for functional genomics, drug screening and, perhaps eventually, cell and gene therapy," he writes.
+Cram says it's also more efficient to use fresh embryos because freezing can damage them.
+He says the group will also apply to import stem cell lines created from abnormal embryos internationally to "cover all our bases" in case the application for a licence is unsuccessful.
+Ethical issues
+Associate Professor Sue Dodds, from the University of Wollongong specialises in feminist approaches to bioethics.
+She says the biggest ethical issues about using fresh embryos relate to the potential to put pressure on women to provide embryos on demand for research, rather than creating them as part of a legitimate IVF process.
+She says there are also perceptions about the so-called "slippery slope" towards production-line approaches to human life.
+"As a matter of public policy it's been decided that we cannot create embryos for the purpose of research ... [but can only] use ones that would otherwise be destroyed because they're not being used for IVF," she says.
+
+Ice crystals from cirrus storm clouds can regenerate, say scientists who have caught them on film
+Cirrus clouds don't just form and die, but can regenerate, detailed images of ice crystals show.
+The pictures are some of the first results to come out of the Tropical Warm Pool International Cloud Experiment being conducted from Darwin by the Australian Bureau of Meteorology and international researchers.
+The information will improve our understanding of the life cycle of these high-altitude clouds and help us to make better predictions about climate change, the scientists say.
+US researcher, Dr Jim Mather from the Pacific Northwest National Laboratory, says it's been speculated that cirrus clouds can regenerate.
+But the latest images have "caught them in the act".
+In older clouds, the ice crystals are small and pristine, which suggests they are newly formed.
+"In older cirrus the crystals are actually being regenerated," he says.
+"They're growing fresh crystals, so while the cloud appears to be a continuous sheet extending well out from the storm there's actually a life cycle within the cloud."
+Thin and wispy
+Cirrus clouds are the most common high-altitude cloud and can be found at altitudes of 8-17 kilometres from the surface of the Earth.
+They can form sheets of up to 1000 kilometres across at temperatures between -20&deg; and -70&deg;C.
+These thin and wispy clouds are made of tiny ice particles. They are a by-product of storms, lasting up to 12 hours afterwards.
+Mather says cirrus clouds are an important factor in climate change because of the role they play in the interchange of solar energy between space and the Earth.
+"If temperatures increase, what will be the effect on these clouds? Will they increase or decrease in area or extent? Because that can have an effect in either warming or cooling the climate," he says.
+The images confirm that at higher altitudes there are some very small, spherical particles, about 20 micrometres in diameter.
+More complex crystalline shapes were found at lower altitudes at the base of the cloud.
+Mather says scientist have been discussing what shape ice crystals you might find at very high altitudes and very low temperatures.
+"There's been an expectation that if you look at a freshly produced cloud from a thunderstorm it's going to be quite complex as the particles crash into each other and form large aggregate chains.
+"But as you get well away from the storm you expect to get more pristine crystals.
+"Actually seeing these images and confirming the ideas ... was really an epiphany."
+
+Australian women should be given the option of taking a pill to terminate a pregnancy, advocates of the RU-486 drug say. But not everyone agrees
+The abortion drug RU-486 is not like most drugs that chug through Australia's regulatory system.
+Rarely has the availability of a drug been tied to such charged emotions, including headlines that warn of backyard miscarriages for desperate women.
+Part of the debate, which is due to come to a head in a parliamentary vote later this week, relates to the drug's safety and efficacy.
+Does RU-486, otherwise known as Mifeprex or mifepristone, have side-effects? And how does it compare with surgical abortions?
+Under the current system, the conservative, Catholic, anti-abortion health minister Tony Abbott, has the final say on the drug.
+But advocates of RU-486 say that decision should rest solely with health experts at the Therapeutic Goods Administration, as it does for other drugs in Australia.
+Heated debate
+RU-486 was developed in France in the 1980s and is used for terminating a pregnancy at less than nine weeks.
+Sexual Health and Family Planning Australia says RU-486 has been used by more than 21 million women around the world and is available in 35 countries, including the UK, US, New Zealand, France, Sweden, Greece and Spain.
+The drug works by blocking the effects of the hormone progesterone, which a woman needs to start and maintain a pregnancy.
+It breaks down the lining of the uterus, which can no longer hold onto the fertilised egg.
+Usually, the woman has to return to her doctor two days later for a prostaglandin, a drug that causes her uterus to contact and expel the products of conception.
+How safe is it?
+Associate Professor Anne Tonkin, a clinical pharmacologist from the University of Adelaide and a drug adviser to the federal government, says:
+"Mifepristone ... is not a risky drug, and is not a particular threat to women's safety. It is not a poison or a toxin, and has very few side-effects.
+"It works by mimicking a common cause of natural miscarriage. The side-effects are the same as those of a spontaneous natural abortion, and include bleeding as part of the normal response."  
+She says that in 95% of cases, a miscarriage induced by mifepristone used in combination with a prostaglandin requires no further treatment. 
+"In about 5%, as is the case for natural miscarriage, a minor surgical procedure is required to complete the abortion. This means that 95% of women who would otherwise have required an operative procedure could avoid it with the use of mifepristone," she says.
+But a study that looked at all side-effects of the drug reported to the US Food and Drug Administration over a four-year period found there were serious effects.
+These included four otherwise healthy women who had died from bleeding or septic shock after taking the drug, the most common side-effects reported by all women.
+Of the 607 adverse events analysed in the February issue of the Annals of Pharmacotherapy, there were women who reported foetal abnormalities that appeared after failed abortion attempts, ruptured ectopic pregnancies and allergic reactions.
+Emergency access
+Chief medical officer Professor John Horvath has been concerned about the risks of later side-effects in some women who take the drug.
+In written advice to the health minister on the safety for women in remote areas, he says RU-486 "carries a significantly higher risk [than surgical abortion] of later adverse events".
+And he says that if doctors are not supported by services that could deal with emergency complications out of hours, this would "substantially increase the risks to women undergoing termination".
+Another recent study, published in the journal Contraception, concludes the "safety of mifepristone is high".
+When it analysed the results from more than 95,000 RU-486 abortions in the US, it found few serious medical complications in everyday use.
+Some 2.2 per 1000 women had a complication, most commonly heavy bleeding. And 1.1 per 100,000 women died after taking the drug.
+By comparison, the mortality rate from surgical abortion was 1 per 100,000 women.
+Others have argued that rather than debating which abortion method is best, the aim of the current debate is to offer women a choice.
+The Royal Australian and New Zealand College of Obstetricians and Gynaecologists, for instance, argues that RU-486 should be an option.
+Many politicians are yet to reveal whether they back availability of RU-486, so it is unclear which way parliament will vote.
+But debate on the drug is likely to continue regardless of the outcome.
+
+At least 23 companies have raced to register the domain name sex.eu
+Hundreds of thousands of businesses raced to snap up '.eu' internet domain names, with 'sex.eu' taking the prize for the most sought-after address on the first day companies could apply.
+Two months after the .eu domain name was launched for public institutions and trademark holders, the tag was opened up to companies other than those seeking a site for a brand, as well as for art works and literature. 
+Within the first hour, sex.eu domain had received 23 applications, followed by schumacher.eu with 15, realestate.eu with 12 and business.eu also with 12 applications, according to the European Registry of Internet Domain Names (Eurid). 
+In the first 15 minutes Eurid, a nonprofit organisation appointed by the European Commission to manage requests, received 27,949 applications overall and after one hour the number had risen to 71,235. 
+The .eu domain name is not supposed to replace national endings such as .fr and .de but rather offer the possibility of a pan-European identity in cyberspace. 
+Germans led the way by mid afternoon making up a little more than 30% of the total applications received to date followed by the Netherlands with 16% percent and France with just over 10%. 
+Individuals will have to wait until the second quarter of 2006 before trying to get access to their own veritable European piece of the internet. 
+For updates on who's applying for the .eu domain name, see the Eurid website.
+
+This kentia or thatch palm grows near its sister species, the curly palm. So how did the two species arise when there are no geographical barriers between them?
+One of the world's best examples of sympatric speciation, when two species from a single ancestor form in the absence of a geographical barrier, has been found among the swaying palm trees on Australia's Lord Howe Island.
+Researchers have found two sister species of palms living side by side on the tiny World Heritage listed island 580 kilometres off Australia's east coast.
+The two species, the kentia or thatch palm (Howea forsteriana) and curly palm (H. belmoreana), appear to have diverged after they began flowering at different times of year, probably as a result of differing soil preferences.
+The international team of researchers, including those from the UK's Royal Botanic Gardens, Kew, reports its findings online today in the journal Nature.
+It's generally accepted that evolution occurs by one species breaking into two by the process of allopatric speciation.
+This might occur when, say, a mountain range separates a species and the two populations change gradually until they become so different they can no longer interbreed.
+But there are also theoretical reasons to believe that a species can split into two within its own area, a phenomenon known as sympatric speciation.
+The researchers used a range of techniques to show that the palm species are sisters and indeed diverged much more recently than the island's creation by volcanic activity 6.4-6.9 million years ago.
+They calculate that the palms' common ancestor probably arrived from mainland Australia as long as 4.5-5.5 million years ago. And more recently, H. forsteriana diverged from its related species, an ancestor of H. belmoreana.
+Soil is the key
+They note that the flowering times of the palm trees differed on different soils, indicating the ancestors of the two species may have adapted to different soil types.
+They add that perhaps living on those different soil types modified the palm trees' flowering times, reducing their chance of interbreeding.
+"That's probably what kick-started the speciation process and resulted in them finally being two separate species," says Associate Professor David Rowell, from the Australian National University, Canberra.
+"This paper is very clever because it uses Lord Howe Island, which is very small, and where it is very unlikely that a species would be split into two, and so therefore it seems to be very strong evidence that sympatric speciation has occurred in this case.
+"That being the case, it lends strength to the models, hypotheses and theories that people have put up about how evolution works."
+Fishy clues to new species
+Meanwhile, German researchers have discovered another case of apparent sympatric speciation, this time in two species of fish in Lake Apoyo crater, in Nicaragua.
+A report in today's Nature says the lake is just 5 kilometres across and less than 23,000 years old. But DNA profiling shows that, during that time, it was colonised by the species Amphilophus citrinellus, which gave rise to A. zaliosus.
+
+This owlet nightjar is one of the species found in the 'lost world' of West Papua, a world where animals show no fear of humans
+The lost world largely untouched by humans that was recently unearthed on West Papua may be the last such find on Earth, an expedition scientist says.
+His comments follow the discovery of a world teeming with new species, giant flowers and rare wildlife showing no fear of humans.
+Australian, US and Indonesian scientists, led by Conservation International (CI), say they found the 300,000-hectare paradise in the Foja Mountains of the Indonesian-controlled province during an expedition late last year.
+The local Kwerba and Papasena people, who are customary landowners of the forest, acted as guides and naturalists.
+"The first bird I saw when I got out of the helicopter turned out to be a new species of honeyeater," says team member Kris Helgen.
+The bird was an orange-faced honeyeater, a bird with a bright orange face-patch.
+Helgen, who is completing a PhD under Dr Tim Flannery of the South Australian Museum, says the honeyeater is the first new species of bird found in New Guinea since 1940.
+"Seeing that as the first bird was the clue that we were onto something big," he says.
+The team also captured the first photos of the male Berlepsch's six-wired bird of paradise (Parotia berlepschi) in its natural habitat.
+This bird was one of a number first collected in the late 19th century by indigenous hunters and sent to Victorian England where it was described as being of "unknown location". Several subsequent expeditions failed to find the bird.
+"It's definitely an area of great biological novelty," says Helgen. "There are lots of things found in these mountains that are found nowhere else."
+The team took the first photos of the golden-fronted bowerbird (Amblyornis flavifrons) displaying at its bower, a tower of twigs and other forest materials it builds for the mating ritual.
+The bowerbird, like the bird of paradise, had been collected in Victorian times but no one knew where it came from.
+In 1979, University of California's, Professor Jared Diamond was the first to demonstrate that the Foja Mountains was the true homeland of the bowerbird.
+A lost world
+Helgen says while Diamond made observations of a number of birds in the Foja Mountains, he did not collect data or specimens.
+"We were the first to mount the true scientific expedition," he says.
+Helgen says, apart from the reports from Diamond, there is no evidence that humans have ever been to the mountain range. Even the locals who took part in this latest research had never been there. 
+The researchers say the area is probably a 15 or 20 day walk from the nearest village.
+"Not only are there no people but there are no things that people bring with them: rats, dogs, pigs," says Helgen, adding these animals affect native fauna.
+"It is a world that's been lost elsewhere," he says. "Much of the world would have looked like that at some point.
+"What's so interesting and unique is that it might be last time this is ever done: high adventure, true exploration of a place where no one has set foot hardly."
+Animals without fear for people
+The team also found mammals that show no fear of humans. For example they were able to pick two long-beaked echidnas, a primitive egg-laying mammal, that had been hunted to near extinction elsewhere.
+"The animals there just don't know people because people have never lived here. That's a very, very rare thing in this day and age," says Helgen.
+The team also found a golden-mantled tree kangaroo (Dendrolagus pulcherrimus), which had previously only been found on a single mountain in neighbouring Papua New Guinea.
+And they found new species of plants including the largest rhododendron flower on record, almost 15 centimetres across, more than 20 new frogs and four new butterflies.
+Pretty impressive
+Dr Ken Aplin, an evolutionary biologist who specialises in mammals of Australia and New Guinea, describes the find as  "pretty impressive" and agrees the remoteness of the Foja Mountains explains why it is in such pristine condition.
+"People will generally hunt within a days travel of the village," says Aplin of CSIRO Sustainable Ecosystems, currently based at the Kyoto University Museum in Japan.
+Aplin says mountain ranges such as Foja originally started life as a series of oceanic islands off to the north of New Guinea, which over time, came closer and closer to the main central range and connected up in the past million years.
+"So they were evolving their own faunas prior to becoming part of New Guinea," he says.
+Other ranges along the north coast the Foja range would have evolved unique species too, he says, but their biodiversity would have been affected by humans, feral pigs and dogs.
+"In a global context it may well be unique or very nearly so, in being one of the last places that is not showing any impact at all of human activities."
+The expedition was co-sponsored by the Indonesian Institute of Science (LIPI) and received funding from the Swift Foundation, the Gordon and Betty Moore Foundation, the National Geographic Society and the Global Environment Project Institute.
+
+This dinosaur, Guanlong wucaii, lived millions of years before T-Rex and is the oldest tyrannosaur ever found
+It had an odd-looking crest and long arms, but a fossil dug up in a remote Chinese desert is the earliest example yet found of a tyrannosaur, scientists report.
+The creature, named Guanlong wucaii, lived 160 million years ago, more than 90 million years before Tyrannosaurus rex.
+It shows the tyrannosaur family had an extensive history, the researchers report in today's issue of the journal Nature. 
+"Guanlong is the oldest and most primitive tyrannosaur," says Professor James Clark of George Washington University, who helped to lead the study.
+T. rex, the best-known tyrannosaur, lived 65 million to 70 million years ago, during the Cretaceous period. This latest find is 90 million years older. 
+"It is really pushing the record of tyrannosaurs back into the Jurassic," Clark says. 
+Clark's team found two examples of the early tyrannosaur in the Junggar Basin in northwestern China, a largely unexplored cold desert.
+Back in the Jurassic, the area would have been a large wetland bounded by mountains, says geologist Dr David Eberth of the Royal Tyrell Museum in Alberta, Canada.
+It would have been warm, with sporadic volcanic explosions, he says. 
+"These animals were found in mud rock," says Eberth, adding the deposits were made of sand, clay and volcanic material that secured the fossilised bones for millennia.
+The wind has now eroded the dried deposits of tens of millions of years. "It is very easy to see what is in the rocks, what is coming out of the rocks," Clark says. 
+The researchers camp out in the desolate region in the summers, working between sandstorms. They hire local people to walk across the rocks, systematically searching for protruding fossils. 
+Sharp teeth
+It was one such employee who spotted a bit of Guanlong sticking out and eventually the palaeontologists dug up two nearly complete skeletons, one on top of another. 
+"We knew right away that this was a theropod dinosaur," Clark says. It had sharp teeth and clearly was a two-legged animal. 
+But one of the two specimens had an unusual, thin crest on its head, and there was a place on the second skull where one appeared to have been broken off. 
+"It's a very unusual skull with this crest coming off it," Clark says. "It doesn't immediately shout tyrannosaur when you first see it."
+But other identifiers marked it as a tyrannosaur, including distinctive structures in the pelvis. 
+The thin crest probably was used for display, Clark says. It has been coloured red in the reconstruction, although scientists have no idea what colour it would have been. 
+They have also given the animal bright purple feathers.
+"We have no evidence of feathers in this species," Clark says. "But there is evidence of feathers in another primitive tyrannosaur. We are fairly confident that it did have feathers." 
+Dr Gregory Erickson of Florida State University studied the 'growth rings' in the animals' shin bones and determined that one specimen would have been about seven years old and thus a juvenile, and the other a 12-year-old adult. 
+The creatures were about 3 metres long, compared to T. rex, which reached lengths of 14 metres. They do not have T. rex's shortened forelimbs.
+The researchers, led by Dr Xu Xing of the Institute of Vertebrate Palaeontology and Palaeoanthropology at the Chinese Academy of Sciences in Beijing, named the new dinosaur Guanlong wucaii.
+The genus name is derived from the Mandarin word for 'crowned dragon' and species name refers to the region where it was found.
+
+Be careful what you wish for this Valentine's Day
+French kissing puts teens at greater risk of contracting meningococcal disease than their lip-pecking counterparts, UK research shows.
+While intimate kissing with multiple partners appears to increase the risk of contracting the disease, the UK study found that recently attending a religious event was associated with a low risk.
+The study, published this week in the British Medical Journal, involved about 300 teenagers aged 15 to 19 who had been admitted to hospital with a meningococcal infection.
+Lead researcher, Professor Robert Booy, co-director of Australia's National Centre for Immunisation Research and Surveillance at the Children's Hospital at Westmead says that the microbes that we normally carry in our throats are readily transmitted to another person through intimate kissing.
+For meningococcal disease, this is the bacteria Neisseria meningitidis. Infection can lead to blood poisoning (meningococcal septicaemia), inflammation of the outer lining around the brain and spinal cord (meningococcal meningitis), or a combination of the two.
+"When microbes that cause meningitis are transferred from one person to another, the body's immune system is normally able to repel them and they don't do any harm," he says.
+"But if by chance you have a sore throat because of a smoky atmosphere or an existing virus, the inflammation in your throat disrupts the protective epithelial membrane.
+"This makes it easy for the meningococcal microbes to pass through the lining of the throat into the blood stream and travel up to the brain where they cause meningitis."
+But teens who avoid smoky parties and don't kiss with a sore throat may still be at high risk, the study suggests.
+University students are a high-risk group, the study shows, as are teens who were born pre-term or who had glandular fever. Substance misuse was another high-risk behaviour.
+"Our research suggests that vaccination is still the most effective way to reduce the risk of meningococcal disease. But behavioural changes remain important because the vaccines available don't protect against all causes of meningococcal diseases," Booy says.
+He speculates that teens with a religious lifestyle may have fewer opportunities to exchange saliva, thus putting them at low risk of the disease.
+"Believers might prefer to account for this particular finding as the power of prayer. Or it could be that the non-church goers lied about their kissing activities," he says.
+
+The nearby supernova 1987A in its dying moments
+Milliseconds before a giant star dies in a spectacular explosion, it hums a note around 'middle C', astronomers say.
+In the April issue of The Astrophysical Journal, Professor Adam Burrows of the University of Arizona and team will report the song that immediately precedes the explosion of a supernova.
+"We were quite sure when we started seeing this phenomenon that we were seeing sound waves, but it was so unexpected that we kept re-checking and re-testing our results," says Burrows.
+Astronomers have long been trying to understand what happens when a supernova, a massive star, collapses and explodes.
+Once it reaches death's door, a supernova's core is so dense that it does not allow energy to escape, and the star collapses inwards towards the core.
+Until now scientists had assumed that the spectacular explosion in a star's dying moments was due to the star's outer shell bouncing back off the core.
+But, says Australian supernova expert Dr Stuart Ryder of the Anglo-Australian Observatory in Sydney, none of the models of exploding supernovae to date have supported this theory.
+Basically the models don't show enough energy coming from the core bounce to overcome the collapsing outer layers.
+"The stuff trying to expand would keep running into the stuff that is still collapsing and it would literally stall the explosion," says Ryder. 
+There have been various attempts to tweak the models, including taking account of  neutrinos, which are emitted from supernovae.
+But scientists found that these subatomic particles also do not provide enough energy to make the models work. The models still stalled before the explosion.
+Sound waves provide missing link
+Burrows and team have now developed computer models to simulate the events of a dying star, from the collapse of the core through to the supernova explosion.
+"Our simulations show that the inner core starts to execute pulsations," says Burrows.
+"They show that after about 500 milliseconds [after the core collapses] the inner core begins to vibrate wildly. And after 600, 700 or 800 milliseconds, this oscillation becomes so vigorous that it sends out sound waves.
+"In these computer runs, these sound waves actually cause the star to explode, not the neutrinos."
+The researchers say typical sound frequencies in the inner core are about 200 to 400 hertz, in the audible range around middle C.
+A million steps
+The new models involve a million steps and simulate the full second between core collapse and explosion. 
+Previous models, which did not take into account sound waves, had only one fifth the number of steps and simulate only the first few hundred milliseconds after core collapse.
+Ryder says Burrows and team could have found the "missing link" in understanding what makes stars explode.
+"It seems that we haven't properly allowed for these sound phenomena in the core of the star when it collapses," he says.
+"This might be like the death knell or the last alarm bell that something bad is about to happen."
+
+Disabling a memory molecule in the brain lifts depression in mice as effectively as using antidepressants, researchers say
+New fossils found in Australia tell us that enormous snakes evolved from predatory lizards like goannas, scientists say.
+Palaeontologist Dr John Scanlon describes the well-preserved 25 to 20 million-year old snake skulls from the Riversleigh World Heritage site, in today's issue of the journal Nature.
+"There's been quite a bit of controversy about what sort of lizards snakes evolved from," says Scanlon, of the Riversleigh Fossils Centre in Mount Isa.
+He says one idea is that snakes evolved from small burrowing insect-eating lizards that lost their legs and developed an elongated body. 
+Another idea is that snakes evolved from relatively large predatory lizards such as goannas.
+Scanlon says he hopes the skulls, from a now extinct snake known as Yurlunggur, will settle the debate on the evolution of snakes.
+The structure of the jaws and face prove that Yurlunggur, an Arnhem Land Aboriginal term for 'rainbow serpent', is a very primitive snake, says Scanlon.
+"It has so many features in common with lizards rather than other modern snakes."
+For example, Yurlunggur has a clear jugal bone, similar to a cheekbone, not present in modern snakes.
+And, in particular, the skulls show the snake is more closely related to large predatory lizards than to smaller insectivorous ones, says Scanlon.
+"It basically shows a relationship between the most primitive snakes and the varanoid lizards such as goannas and mosasaurs," he says, referring to the giant acquatic goannas that lived during the Cretaceous period.
+
+The galaxy cluster Abell 2029 is composed of thousands of galaxies, shown in this xray image, and an amount of dark matter equivalent to more than a hundred trillion Suns
+Dark matter particles are zooming around the universe a million times faster than anyone predicted, UK astronomers say.
+They've calculated that this mysterious substance, which governs how stars and galaxies move, is moving at a speedy 9 kilometres per second.
+The University of Cambridge researchers have also worked out how dark matter likes to clump together and surprising details of how hot it is, data essential in modelling how galaxies form.
+A preliminary report is available on arXiv, the online website operated by Cornell University. 
+Dark matter is mysterious because it doesn't emit radiation, making it difficult to spot. Indeed, no-one has detected it and not all scientists are convinced it exists.
+"The best evidence for dark matter is that there are stars in our sky," says Professor Gilmore, director of the Institute of Astronomy at Cambridge, which made the latest calculations.
+"Without it they'd be flying off into space."
+Dark matter is the mass needed to hold stars in their given places as they move around galaxies; the faster they move the more mass is needed.
+"Kepler and Newton were able to weigh the Sun just by knowing where Earth was and how fast it was moving," says Gilmore. 
+"We did the same thing, only in three dimensions, finding the 'weight' of dark matter by measuring the place and speed of a very large number stars in several dwarf galaxies orbiting the Milky Way."
+Hanging out in clumps
+The results were surprising. Aside from their speed, the researchers calculated the smallest clump of dark matter that could exist, 1000 light-years across.
+These results imply that dark matter is hotter than predicted, meaning that what astronomers call 'cold' dark matter may not be so cold after all.
+At 10,000&deg;C it's still cool by astronomical standards. But it's warm enough to solve two problems that have plagued standard models of how galaxies form: that there are too few dwarf galaxies and why dark matter has not concentrated in the centre of galaxies.
+Gilmore says he was initially wary of the results, which together seemed too simple to be plausible.
+The discovery of a super-dim galaxy by Dr Beth Willman from New York University, gave the team an opportunity to successfully test its predictions.
+
+Friendship may be just as important to some primates as it is for humans, new research suggests
+Female baboons that suffer the loss of a close friend or relative turn to other baboons for comfort and support, according to a new study.
+The study encompasses 14 years of observing over 80 free-ranging baboons in Botswana's Okavango Delta.
+It provides the first direct evidence that certain animals mourn the loss of individuals, even when the rest of their social group remains intact.
+The findings also suggest that friendship may be just as important to some primates as it is for humans. 
+Researchers were particularly struck by the behaviour of one female chacma baboon (Papio hamadryas ursinus) named Sylvia.
+She was described as "the queen of mean" and disdainful of other baboons until she lost her daughter, Sierra, to a lion kill. 
+"In the week after Sierra died, Sylvia was withdrawn," says Dr Anne Engh, who led the project.
+"When the other females were grooming and socialising, she tended to sit alone and rarely interacted even with her other relatives." 
+Engh, a postdoctoral researcher in the Department of Biology at the University of Pennsylvania, adds:
+"After a week or two of moping around, Sylvia suddenly initiated grooming with several low-ranking females. I think that they were as surprised as I was; they seemed awfully nervous at first. Eventually, Sylvia settled into close relationships with a very low-ranking female and with Sierra's daughter, Margaret." 
+Relieving stress
+Engh says that grooming is a friendly behaviour similar to two human friends chatting over a drink.
+The activity seems to relax the participants to the point where it can lower stress hormone levels. Those levels rise in humans and baboons after a close friend or relative dies. 
+The researchers measured a group of such hormones, called glucocorticoids, in Sylvia and 20 other females. Baboons that experienced losses had elevated levels of the hormones after the deaths. 
+In humans, this is associated with bereavement, so it is likely that baboons also grieve their dead. 
+The mourning animals then widened their social circles by approaching and grooming other females, even those that were beneath them in rank.
+This appeared to help them cope with losses, since stress hormone levels significantly dropped afterwards.
+The discovery, outlined in a recent Proceedings of the National Academy of Sciences paper, underscores the importance of friendship.
+"Humans and baboons who are more socially integrated have lower glucocorticoid levels," says Engh.
+"Both the human research and our results highlight the importance of friendly social relationships in reducing stress.
+"Female [baboons] usually have one or two close female friends that usually devote a large proportion of their grooming to each other, and they seem to enjoy spending time close together."
+Engh also mentions that friendships form between male and female baboons. For those relationships, the female often grooms the male, while the male protects the female, and any infants that she might have, from predation and bullying baboons. 
+No surprise there
+Brian Craft, lead keeper at the Oakland Zooin California, says that he was not surprised by the findings. 
+"Advanced relationships are seen in chimpanzees, bonobos, as well as baboons and other multi-social troops," Craft explains.
+"Friendships, which may help to ease stress after deaths, can be beneficial to the troop as a whole, as they keep it cohesive. It also appears that friend selection among baboons and other primates is somewhat of a choice, as for humans, and is not just instinctive behaviour."
+
+Simulation of small satellite galaxies orbiting and falling into a larger one 
+Astronomers have released new evidence to show that a region of stars in our galaxy known as the Arcturus stream is the digested remains of what was once a neighbouring galaxy.
+The evidence is among the first to come from the largest star study to date, with data from 25,000 stars just released at a US astrophysics workshop.
+Dr Quentin Parker of Sydney's Macquarie University and the Anglo-Australian Observatory is head of data management at the international Radial Velocity Experiment, or RAVE, which uses Australia's UK Schmidt telescope.
+Parker says the latest results provide a smoking gun for the argument that the Milky Way is a voracious cannibal that devours its neighbours.
+"We've confirmed the Arcturus moving group as being a star stream, which indicates a disruptive galaxy spiralled into our own," he says.
+"Ours is a large galaxy and it has been eating other galaxies; it's been hungry. We can see what it's eaten by the crumbs that are left over from its meal."
+It's another bit of evidence for the now widely accepted cannibal, or accretion, theory of galactic evolution, Parker says.
+According to this theory, the gravitational pull of large galaxies sucks in smaller ones, making large galaxies like our own a sort of cosmic melting pot.
+Parker says the RAVE measurements show stars in the Arcturus group are travelling at a similar velocity and in a similar direction through space, indicating they were once part of a coherent system.
+"Using ... star velocities it's possible for the first time begin to unravel the way our galaxy is constructed," he says.
+The RAVE study is measuring the speed of a million stars in the Milky Way using radial velocity, or the motion of a star along the line of sight between the telescope and the star.
+The huge scope of the survey has been made possible by the six degree field (6dF) spectrograph on the 1.2 metre UK Schmidt Telescope at the Anglo-Australian Observatory, which can obtain spectroscopic information for up to 150 stars at once.
+The telescope splits light from the stars into a wide spectrum of colours and by looking at specific colours produced by calcium atoms astronomers can work out whether the colours have 'shifted' in the spectrum.
+This enables them to work out aspects of the star's movement.
+"We're looking at the stars in our galaxy and measuring their velocity by measuring how their lines have shifted," Parker says.
+The survey has so far collected information about 90,000 stars and will release data on the remaining 65,000 as it's analysed.
+
+The cane toad front is moving across Australia five times faster than it was in the 1940s
+The invasion of the dreaded cane toad across Australia has taken a new turn with research showing the toxic toads are evolving longer legs that allow them to move faster.
+This means they can encroach even faster on new territory, biologists say in today's issue of the journal Nature.
+Cane toads (Bufo marinus) were introduced to Australia more than 70 years ago to control insect pests in cane fields. And their toxic nature and invasiveness have made them a major ecological menace.
+The toads have expanded to cover more than a million square kilometres of the continent and are now progressing at a rate five times higher than in the 1940s to 1960s.
+Professor Richard Shine from the University of Sydney and team stationed themselves at the invasion front 60 kilometres east of Darwin.
+They then waited for the toads, which can travel almost two kilometres a night, to arrive. 
+Measurements revealed that the 'super athletes' at the front of the pack had longer legs than those at the back.
+Why are their legs longer?
+Shine says there are two "possible" and "probable" explanations as to why toads at the front have longer legs.
+The first is the conventional evolutionary reason, that there are advantages to being at the front.
+Toads with longer legs have the first access to virgin territory full of juicy grubs, so the evolving species is favouring this characteristic.
+The second explanation is more immediate and practical.
+"These guys sort themselves out spatially because the only ones that can be at the front are the fast ones," says Shine.
+Put simply, if the faster ones with the longest legs were at the back, they would trample the shorter slower ones ahead.
+"So even if there is no evolutionary advantage to being at the front you are still going to end up with the front guys being the fast movers," he says.
+Understanding the enemy
+Shine says understanding the enemy is the first step in combating the toads in the future.
+"People tend to take a very straightforward view that cane toads are bad and we just have to work out ways to kill lots of them. But history is telling us that that doesn't work that well," he says.
+"What we need to do is find what kind of animal toads really are, what bits of the landscape they use, how they use it and what they depend on."
+
+A new type of pulsar that spits out radio waves intermittently, rather than regularly, has been discovered
+Scientists have discovered a strange new type of pulsar that emits intermittent bursts of radio waves. 
+And there are lots of them out there. 
+In a paper in the journal Nature today, an international team of astronomers estimates there could be up to half a million of these weird flashing 'dead' stars.
+The scientists are calling them RRATs, or rotating radio transients.
+Unlike ordinary pulsars, which can emit regular pulses of radio waves, RRATs emit short millisecond bursts of radio waves in between dark spells that may last several hours. 
+This makes them very difficult to find, says co-author Dr Dick Manchester, from CSIRO's Australia Telescope National Facility, who has been hunting pulsars with the Parkes Radio Telescope for the past seven years.
+"These things are so sporadic that most searches, like the survey we conducted, would have missed them. We only looked at each patch of the sky for 35 minutes so we were lucky to find any," he says.
+"This means there must be a huge population out there, many more than ordinary pulsars." 
+While there are about 100,000 ordinary pulsars in the Milky Way, astronomers estimate there are at least 400,000 RRATs.
+This latest research could mean that scientists will have to come up with new ideas for the way so many RRATs have formed. 
+Birth of a pulsar
+Pulsars are believed to be formed in supernovae, the cataclysmic explosion that signals the end of the life of a massive star.
+As the core collapses to a superdense neutron star it spins very rapidly, sending a beam of radiation that sweeps out like a searchlight.
+If the beam is pointing towards Earth each 'pulse' can be detected, hence the name pulsar.
+"We knew that RRATs were pulsars, even though the pulses were isolated, just a single burst and then they might shut up for an hour or two," says Manchester.
+"But it was only by timing them over a four year period that it was realised that they had much longer periods than normal and that they were slowing down."
+Magnetic, reborn or just plain weird?
+The paper suggests that RRATs are young super magnetic pulsars barely 100,000 years old.
+But Manchester is not ruling out the possibility that they may be 'zombies', old pulsars suddenly brought back to life by growing magnetic fields or ordinary pulsars radiating in an unusual way.
+"That's what makes it exciting," he says. "There are so many possibilities."
+
+Women value a good sense of humour in a potential male partner, even if his jokes are crass. But men don't rate humour so highly in women, new research shows
+It's a trait often requested in lonely hearts ads and scientists have now shown that a good sense of humour is important for women, but not men, in choosing a romantic partner. 
+A woman is even willing to overlook other shortcomings in a man if he can make her laugh, North American researchers say in the journal Evolution and Human Behavior. 
+"Our results suggest that humour can positively affect desirability as a relationship partner but this effect is most likely to occur when men use humour and are evaluated by women," says Dr Eric Bressler, an assistant professor at Westfield State College in Massachusetts. 
+Bressler and Canadian researcher Dr Sigal Balshine, an assistant professor at McMaster University in Ontario, demonstrated in an experiment that a good sense of humour, or GSOH as it appears in personal ads, does make a difference. 
+They showed groups of women pictures of two equally attractive men and presented autobiographical statements that were either funny or serious. 
+After reversing the experiment and showing groups of men photographs of two women, they asked both sexes to select who they would choose as a romantic partner.
+The humorous people were seen as more socially adept but less trustworthy, honest and intelligent. Men did not select the funny person but women did. 
+"Women chose funny men as relationship partners despite often rating them as less honest and intelligent," the researchers say.
+Funny men were preferred even if their humour was unsophisticated, the researchers add.
+
+Can censoring scientists be justified? No, according to the CSIRO scientists who say they've been banned from talking to the public about aspects of climate change
+Allegations the Australian government has pressured some of its top scientists to keep quiet about the implications of climate change are just the tip of the iceberg of scientific censorship, commentators say.
+According to the claims, aired on ABC TV's Four Corners program last night, senior CSIRO scientists Drs Graeme Pearman, Barney Foran and Barrie Pittock were regularly gagged from commenting on so-called policy issues, such as greenhouse gas emission targets and environmental refugees.
+But at least one expert says there are times where government censorship of scientific research is justified and may be necessary.
+Dr Michael Selgelid, who lecturers in bioethics at the University of Sydney, questions whether scientists should be able to publish research that could endanger the public.
+For example, information that could be used to make nuclear weapons is censored and "we've been living with that for the last 60 years", he says.
+He says governments should similarly be able to block publication of research that provides information about making biological weapons.
+"If someone discovers an easy way of making something that's just as dangerous and contagious as smallpox  ... there would be really good grounds for censoring it despite the fact that free speech is important and that scientific openness is important."
+He disagrees with suggestions that it should be a matter for journals to censor what they publish or for scientists to censor themselves.
+"Scientists just don't have that kind of expertise and ... sometimes it's only the government that's going to have the information that's needed to do the risk assessment," he says.
+Vested interests
+Censorship is a different matter when it comes to the influence of vested interests, says Brian Martin, an associate professor in science, technology and society at the  University of Wollongong, who has published articles on the suppression of dissent in science.
+He says this form of censorship is alive and well in Australia.
+"In all my studies the thing that stands out is that a few cases that have become prominent. But for every one of those these's at least 10, maybe as many as 100 other cases which never receive any publicity," he says. 
+Dr Mark Diesendorf is a former CSIRO chief scientist and is now a senior lecturer in environment studies at the University of New South Wales.
+He accuses CSIRO of gagging him during the 1970s and 80s when he was involved in renewable energy research.
+He says history is repeating itself with the latest allegations and with CSIRO's recent decision to move away from renewable energy research.
+"Everyone at [CSIRO is] terrified the federal government will cut their budget unless they do exactly as they're told ... that and suppression of the [atmospheric research scientists] is well know to us who work in the energy policy field," he says.
+A spokeswoman for CSIRO declined to comment, saying "I don't think we can possibly comment on something that happened 20 years ago."
+She also describes Diesendorf's comments on a fear of budget cuts as "absolute rubbish".
+Withholding funding
+Diesendorf says withholding funding is another form of censorship, with many research grants now subject to ministerial approval and what he describes as unequal funding for Cooperative Reserch Centres (CRCs).
+"There are three [CRCs] for fossil fuels [and] zero for renewable energy," he says.
+"Research development for solar energy has shrunk, and there is no funding for windpower."
+Diesendorf says he's particularly worried about what he describes as the "blatant muzzling" of scientists.
+He says this means we risk policy decisions being made by vested interests such as big business, the military and powerful professions.
+"Scientists are people who have expert knowledge so it means that policy decisions are made without expert knowledge or by the expert knowledge of vested interests only," he says.
+"The very least we can expect in a democracy is that all sides have a right to present evidence that's relevant to policy."
+Martin says we should be very worried about scientific censorship because it can affect human life.
+"With climate change we're talking about risk to future generations. It's something that society should be paying attention to, it should be put on the agenda without fear or favour."
+But censorship doesn't appear to be a universal experience for scientists.
+"I have never been gagged about what I say to the media," says Monash University's Professor Patricia Vickers-Rich in a response to a poll by the Australian Science Media Centre.
+"This is not a problem for this scientist. And that relates not only to issues on climate change, but also on issues relating to intelligent design, population, AIDS ... and I am frequently vocal on these issues."
+
+Babies have an innate ability to do simple maths. While counting toes is beyond them, then can match voices to the number of people in a room
+Even before babies learn to talk they have a bit of a grasp of maths, according to new research concluding that infants may have an abstract sense of numerical concepts. 
+The US research, published in the latest issue of Proceedings of the National Academy of Sciences, says seven-month-old babies demonstrate an ability to match the number of voices they hear to the number of faces they expect to see. 
+The study of 20 infants by researchers at Duke University was similar to a previous experiment to demonstrate that monkeys show numerical perception across senses. 
+In the new study, babies listened either to two or three women simultaneously saying the word 'look'. 
+At the same time, the infants could choose between video images of two or three women saying the word. 
+As they had found with the monkeys, the researchers say the babies spent significantly more time looking at the video image that matched the number of women talking. 
+"As a result of our experiments, we conclude that the babies are showing an internal representation of 'two-ness' or three-ness' that is separate from sensory modalities and thus reflects an abstract internal process," writes researcher Dr Elizabeth Brannon, an assistant professor in psychological and brain sciences. 
+"These results support the idea that there is a shared system between preverbal infants and nonverbal animals for representing numbers," she says. 
+"What we do know is that somehow, very quickly, [the babies] acquire this ability to perceive number and divorce it from the sensory information." 
+Understanding the research could be useful in devising methods for teaching basic maths skills to the very young, Brannon says.
+
+The hormonal changes that teenage girls go through when they start their periods may explain why they have trouble sleeping
+Adolescent girls appear to be at greater risk of insomnia after they begin menstruation, a study has found.
+This suggests that hormonal changes play a role in developing the sleep disorder, the researchers say in the journal Pediatrics. 
+Researchers found that among more than 1000 13- to 16-year-olds in the study, nearly 11% had suffered insomnia at some point.
+Insomnia, based on formal clinical criteria, was defined as problems falling asleep or staying asleep at least four times a week for a month or longer. 
+Typically, the study found, the teens started having sleep disturbances around the age of 11.
+Before menstruation, girls were about as likely as boys to have insomnia.
+But after they began their menstrual periods girls had more than twice the risk of insomnia as boys.
+The findings suggest that the hormonal changes that come with menstruation contribute to girls' insomnia risk, according to the authors. 
+Such a physiological reason is one of two broad explanations for why menstruation would be related to insomnia, says lead author Dr Eric Johnson. 
+The other possibility is that the physical changes that come with puberty, like breast development, create "social pressures" that contribute to sleep problems, says Johnson, a researcher with RTI International.
+But he says menstruation is related specifically to problems with staying asleep and getting enough deep sleep. 
+These forms of insomnia are more likely to have physiological causes, whereas problems with falling asleep in the first place can often be stress-related. 
+In addition, girls' higher risk of insomnia was not explained by higher rates of depression, which is often marked by sleep disturbances. 
+A long lasting problem
+Another key finding, Johnson says, is that of all teens who ever suffered insomnia, 88% also had symptoms at the time of the study. 
+This, he says, signals that the problem is lasting for many teenagers. 
+"Insomnia seems to be common and chronic among adolescents," Johnson and his colleagues conclude. 
+Given the consequences of sleep deprivation among teenagers, including blunted mental acuity, poorer school performance, and even poorer physical and emotional health, prevention and treatment may need to become "important priorities", the researchers say. 
+Therapies for insomnia include lifestyle changes to promote sleep, like getting to bed and rising at regular times each day, cognitive behavioral therapy and sleep medications.
+
+A voodoo follower at an international celebration of voodoo spirituality in the West African country of Benin earlier this year
+Priests who tear out the throats of live chickens in ritual sacrifices to voodoo gods may risk contracting bird flu now the deadly virus has reached Africa. 
+Voodoo priests in Benin, which borders Nigeria where an outbreak of the deadly H5N1 virus was found in poultry last week, sacrifice animals to invoke blessings or favours from the gods. 
+Officials in the tiny West African country, which is the home of the ancient religion, say spreading the word about bird flu may help to save the lives of voodoo devotees. 
+"We have identified the groups at risk, including fetishists and followers of the voodoo cult who sometimes kill animals with their teeth," says Guillaume Hounsou-ve, director of livestock at Benin's agriculture ministry.
+Sheep, goats and other animals are sometimes sacrificed, but the favourite offering is a chicken.
+Priests commonly kill birds by ripping their throats out with their teeth or using a knife to cut their heads off.
+Both methods would bring them into contact with chicken blood, one of the ways bird flu is thought to be spread to humans. 
+The disease has killed more than 90 people in Asia and Turkey since 2003. 
+Hounsou-ve and other senior officials in Benin have spent the past few days drafting an action plan to counter bird flu. 
+"We will target our messages, above all in regions where there are 'convents'," says Hounsou-ve, referring to the houses used for voodoo rituals. 
+A common practice
+An estimated 60% of Benin's 7 million people practise voodoo, although many also follow other religions like Christianity or Islam. 
+Voodoo convents are found across Benin but more commonly in southern areas near the Atlantic seaboard. 
+Once known as the Slave Coast, many thousands of Africans were shipped from here by European traders during more than three centuries of slave trading.
+Many took their voodoo beliefs with them to the New World, notably Haiti, where rites and traditions from different parts of Africa met and evolved. 
+Voodoo in West Africa and the Caribbean encompasses a wide range of rituals, from sacrificing animals to dancing, in which devotees fall into trances said to be a form of possession by gods.
+
+Is the court making different rules for copyright protection in the online world?
+Record companies are being given the power to veto the design of new digital communication technologies, say advocates of online civil liberties.
+The claim, by Electronic Frontiers Australia (EFA), comes on the eve of an appeal against a landmark ruling last year against providers of the internet file-sharing software Kazaa.
+Kazaa is one of a number of free software packages that allow people to swap files over the internet.
+Record companies complain that such peer-to-peer file-sharing software leads to people illegally downloading their copyrighted music.
+And last year they took the providers of Kazaa software to the Federal Court of Australia.
+The court found the providers guilty of "authorising" copyright infringement by encouraging millions of users to download music from artists ranging from Powderfinger and Radiohead to Christine Anu and Robbie Williams.
+The court also ordered the providers of Kazaa to modify the software to contain filters that would make it difficult for users to search for copyrighted works specified by the record companies.
+On Monday 20 February, the providers of Kazaa will appeal against this decision. And the EFA, with the New South Wales Council for Civil Liberties and the Australian Consumers' Association, is applying to take part in the appeal.
+EFA is also worried that this Kazaa ruling could one day lead to email providers inappropriately monitoring, filtering or blocking messages.
+Concerns
+Record companies focus on the illegal uses of peer-to-peer file-sharing software. But EFA is worried last year's Kazaa ruling, and the order to modify the software, will hinder people who want to use it legally.
+It says filtering may catch files that are not infringing copyright, for example music already in the public domain or music deliberately distributed free by independent music groups.
+And EFA also doesn't think record companies should be able to control the design of new digital communication technologies.
+"If this type of precedent is allowed to stand," says EFA vice-chair, Dale Clapperton, "it's essentially going to give the record labels a veto power over the development of new technology."
+The Australian Recording Industry Association (ARIA) disagrees.
+"No-one who read the judgement could form this view," an ARIA spokesperson says. "The operators of Kazaa did not even suggest this."
+ARIA also rejects claims that filters will stop legitimate downloads.
+"A well-constructed filter that targets infringing files will have no effect on legitimate files on the Kazaa system," the ARIA spokesperson says.
+A new precedent
+Clapperton says last year's Kazaa ruling shows the court is treating online copyright infringement in a different way to past infringements.
+He says when a court first found an Australian university library guilty of authorising copyright infringement by allowing students to photocopy books, it ruled that libraries should put up warning signs.
+"The court didn't ban the photocopiers, it didn't order that the photocopiers should be modified to reduce the potential that they be used for infringing purposes," says Clapperton.
+Similarly, he says, video recorder were not banned when movie studios complained that they could be used to infringe copyright when taping television programs.
+"If they'd succeeded, we wouldn't have [video] machines today and we would almost certainly not have things like iPods."
+Stifling innovation?
+EFA says it's early days for digital communication software, and if providers are made responsible for how their product is used this could reduce competition.
+"You could end up with a situation where the only people who produce products are the ones already tied in with the music labels," says Clapperton.
+"It really is going to stifle the development of new technologies."
+ARIA rejects these claims.
+"There is no evidence that there is any reduction in competition or innovation following the decision," says the spokesperson. "The opposite has happened with the launch of many more digital download services including iTunes."
+Other possible impacts?
+EFA chair Matt Black is adamant the Kazaa case should be overturned because the precedent could affect email providers, instant messaging and even Google.
+Black says software like Gmail has the capacity for large files to be transferred via the internet and if the principle of the Kazaa ruling is applied here, you may see Google, which runs Gmail, filtering email.
+"Then you're looking at a situation where very important communications are being monitored, filtered and potentially blocked inappropriately by your email provider."
+
+There's more to the flow of water down terraces like these than meets the mathematician's eye
+A mathematical equation that attempts to model the distribution of water in rice terraces has convinced one researcher that the Western notion of maths has a lot to learn from other cultures.
+Mathematician Willy Alangui of the University of the Philippines Baguio spoke about his attempt to model rice terrace irrigation this week at the Third International Conference on Ethnomathematics in Auckland, New Zealand.
+Alangui has been studying irrigation in a network of rice paddy terraces built by the indigenous Kankanaey people of the Northern Philippines.
+"I'm trying to understand how water is efficiently distributed in all the paddies," says Alangui.
+The paddies are contained by stone walls and farmers ensure everyone gets enough water by opening and closing inlets and outlets as the water flows from the top terraces to the bottom.
+Alangui developed an equation to model the dynamics of water distribution.
+The model took account of variables such as the amount of water flowing into the system, the rate of evaporation and the size and elevation of the paddies.
+"For me as a mathematician it explained nicely the dynamics that goes on in the distribution of water in the whole network of paddies," he says.
+But when he went back to validate the variables he had used with the Kankanaey people he found his model was seriously flawed.
+It failed to account for one major factor that governs the Kankanaey rice irrigation system: the ethic of co-operation.
+The social responsibility factor
+Alangui found out the system depended on a notion of "social responsibility". 
+Even when water was scarce, people upstream shared water equally with those downstream because they had helped to build the irrigation system in the first place.
+This told him the system would fail if the paddy owner at the top of the hill took more water than was fair.
+Alangui says the failure of his model to capture the ethical dimension of the irrigation system told him that he needed to broaden his perspective as a mathematician.
+In the PhD thesis, Alangui will try and modify the model to include this ethic although, he says, it may not be possible.
+"My mathematics may be deficient," he says. "It's not the be all and end all of everything. It's just one way of looking at the world."
+Ethnomathematics
+Alangui thinks Western mathematics has a lot to learn from other cultures, hence his interest in ethnomathematics, the connections between mathematics and culture.
+He says Western mathematics has become "powerful" and "arrogant" as a field and marginalised other perspectives.
+Maori culture, for example, has a different concept of numbers, says Alangui. While western culture uses the number 'three' as an adjective, in for example the phrase 'three glasses', Maori talk of glasses interacting with each other, and as being in the act of 'three-ing'.
+In Kankanaey culture, he says, there is no concept of a circle as a static object, defined by a centre and a radius. Rather, there is the concept of 'encircling', in which a circle is defined as point moving around a circumference.
+Alangui says mathematicians should ask why the static version of numbers or circles has come to dominate. Interrogating long-held assumptions like this could lead to different and useful concepts in maths, he says.
+He says hyperbolic and elliptic geometry were developed when mathematicians questioned the assumption of Euclidian geometry that two parallel lines never meet.
+Alangui is a member of the Kankanaey people and has a masters degree in pure maths.
+
+Light from Saturn's rings illuminates the storm, where lightning strikes are 1000 more powerful than ones on Earth
+For nearly a month, a huge storm with massive lightning has been raging on Saturn under the watchful eye of the Cassini spacecraft. 
+It was a Cassini ear, a radio receiver, that first detected the storm on 23 January. And this week, scientists finally coaxed an image from Cassini's camera. 
+Sunlight reflecting off the planet's rings provided enough light during the Saturn night for Cassini's camera to pick out the storm and cloud features.
+Researchers now are working hard to identify spots within the storm that could be lightning. 
+The only other place in the solar system besides Earth where lightning has been positively identified is on Jupiter. 
+"Cassini's radio detector is on all the time," says planetary meteorologist Professor Andrew Ingersoll, with the California Institute of Technology and a member of the Cassini science team.
+"Months go by and there is no radio noise from Saturn. Then all of a sudden, in the space of a day, they get it. That's what happened on 23 January." 
+The radio emissions are similar to the popping and crackling that you might hear if you were driving through a thunderstorm with an AM radio on.
+What is generally thought of as radio interference is actually radio waves generated by lightning. 
+Behind the storm
+Scientists are not sure what causes the lighting on Saturn, but they believe it is triggered by the same process that creates lightning on Earth. 
+"On Earth, we think the convection in thunderstorms is important in the process of separating positive charges from negative charges. And if you separate enough charges, you build up a very large potential field between those separated charges," says University of Iowa's Dr Bill Kurth, the deputy principal investigator of Cassini's radio and plasma wave science instrument. 
+"Nature doesn't like that, and it tries to correct the situation by running a current between the two separated charges. That forms a very large spark, there's an awful lot of energy that's released, and it's meant to basically allow the negative charges and the positive charges to get back together again," Kurth says. 
+On Saturn, the phenomena manifests itself on a gigantic scale, with lighting bolts more than 1000 times stronger than strikes on Earth, the radio data reveals. The storm itself spans an area larger than continental US. 
+Why Saturn should have such massive storms is a mystery. The planet gets only about 1% of the sunlight that reaches Earth, so there is much less energy to drive storms, Ingersoll says.
+"Given that, there are two possibilities: one is that you have the same number of storms that you have on Earth, but they are weaker; or two, they are just as strong but there are fewer." 
+While more studies are needed, Ingersoll favours the second explanation.
+"This storm certainly looks more vigorous and the radio emissions are more powerful deep down, [so] there may be more water in the atmosphere than on Earth," Ingersoll says. 
+Amateurs beat the professionals
+The first images of the storm actually came from two ground-based amateur astronomers, not the Cassini spacecraft. 
+From its present orbital perch, Cassini has been unable to image the sunlit side of Saturn.
+The team studying the radio emissions, however, decided to ask the amateur astronomy community if anyone had any pictures of Saturn that corresponded to where radio emissions were coming from. 
+Within hours, two astronomers near Paris submitted the first visual confirmation of the storm. 
+Their findings were confirmed by the Cassini images shot in darkness with illumination from the planet's rings.
+
+Buying a house? New research shows it's best for our unconscious to work on big decisions
+When faced with a major decision, such as buying a car or a house, it's best to do your homework, then forget about it for a while and let your unconscious churn through the options.
+According to the results of a novel study published today in the journal Science, unconscious deliberation may lead to a more satisfying choice than mere conscious deliberation alone, at least for major decisions. 
+Conscious deliberation is fine for the less important, more mundane everyday choices like deciding which shampoo or towels to buy, but not for bigger decisions, the report indicates. 
+Four investigators in the department of psychology at the University of Amsterdam, confirm the value of what they call the "deliberation-without-attention" hypothesis in a series of studies on consumer choice.
+The did the experiments in the laboratory and in real life among shoppers in department stores. 
+Decisions, decisions
+For example, in a car-shopping experiment, participants read a complex series of facts about cars they were thinking of buying. Immediately afterwards, they were given puzzles to keep their conscious selves busy. 
+After working on the puzzles, this group of shoppers reported greater satisfaction with their car choice than the people who were given no puzzles and had to decide which car to buy immediately after consciously pondering the facts. 
+But for making simple decisions, such as choosing between different sets of towels, conscious deliberations were all that was needed to make satisfying choices. 
+There are several possible reasons why conscious thought sometimes leads to poor judgment, the researchers say. Consciousness has a "low capacity" causing individuals to consider only a subset of relevant information and they may inappropriately weight the importance or relevance of this information. 
+In contrast, the human subconscious has a higher capacity to integrate more information, which can lead to better choices. 
+First, gather all the information
+"The take-home message is that when you have to make a decision, the first step should be to get all the information necessary for the decision," says author Dr Ap Dijksterhuis.
+"Once you have the information, you have to decide, and this is best done with conscious thought for simple decisions, but left to unconscious thought, to 'sleep on it', when the decision is complex." 
+The novel finding from these studies is the "idea that we can think unconsciously and that unconscious thought is actually superior to conscious thought for complex decisions", the researcher adds.
+
+Poultry farmers burn chicken carcasses in Nigeria, a country that has just started investigating suspected human cases of the H5N1 bird flu virus. Now scientists are preparing for a worst-case scenario: a human bird flu pandemic
+A human vaccine against the deadly H5N1 strain of bird flu virus has successfully passed the first stages in testing its safety and effectiveness, reports the manufacturer.
+The trial, carried out at the Murdoch Childrens Research Institute with the University of Melbourne and the Royal Adelaide Hospital, recently tested a vaccine made by CSL Ltd of Melbourne.
+CSL today announced that the vaccine triggered an immune response it predicts will equate with "a good level of protection" in "about half" of the 400 healthy adult volunteers tested. 
+And, says Dr Andrew Cuthbertson, CSL's chief scientific officer, the participants got little more than the odd sore arm.
+"It was very reassuring in a safety sense."
+The vaccine was based on a deactivated virus originally taken from a Vietnamese patient. 
+It was then grown up in fertilised chicken eggs, killed and mixed with an aluminium phosphate adjuvant before being given to volunteers.
+Cuthbertson says the trial found immune stimulation occurred at two antigen doses of 7.5 microgram and two of 15 micrograms, although greater stimulation occurred at the double 15 microgram dose, which is the dose used in normal flu shots.
+While it is generally assumed the higher the immune stimulation, the greater the protection, Cuthbertson says no one knows yet precisely what immune level will protect. 
+Further safety and efficacy studies
+CSL says it now plans to organise a second trial to study the safety and effectiveness of the vaccine in 800 other healthy volunteers, in particular children and older people who respond differently to vaccines.
+It also plans to test the impact of higher doses of vaccine to clarify the dose that gives the best immune response.
+He hopes the vaccine could be registered some time in the first half of 2007.
+But, says Cuthbertson, if the vaccine is eventually registered, it will be a matter for governments and regulatory agencies to decide the lowest dose that can protect the most number of people.
+How ready are we?
+CSL says if a bird flu pandemic arrived now, and it was directed by the government to do so, they would be able to produce the vaccine as it is in six weeks.
+But, if the pandemic strain mutated from the H5N1 to a strain more readily transmitted to humans, he says the time frame could be stretched.
+"If [the virus] was not too different we would proceed to crank out as much vaccine as possible of the one that we made already," says Cuthbertson.
+If it was very different CSL would have to switch to making a new vaccine and this would take another six weeks.
+Cuthbertson says registering a vaccine against the H5N1 strain will still save time even if the eventual pandemic strain is different because the Therapeutic Goods Administration has told CSL it would not have to repeat clinical trials.
+"It's making the assumption that the safety profile and so forth will be similar," he says.
+Other trials?
+While there have been many attempts to make a vaccine around the world, there have been few results of clinical trials announced, says Professor Aileen Plant, chief executive officer of the Australian Biosecurity Cooperative Research Centre at Curtin University and a consultant to the World Health Organization.
+"It is exciting, really ... I don't think there's been anywhere else that's been able to get that sort of immunological response with two doses of 15 micrograms," says Plant, who also sits on the federal government's National Influenza Pandemic Action Committee.
+She says a US trial last year that did not use an adjuvant had to give substantially more antigen to get an immune response, which means fewer people could be vaccinated.
+Plant agrees that the vaccine could be used in an emergency, despite the missing data on children and elderly people.
+"If the pandemic came tomorrow, the risks would be so high that we would say that it was worth going with it even if we didn't have the data."
+
+Researchers have put insulin producing cells like this into tiny capsules as a treatment for type 1 diabetes
+Encapsulating insulin producing cells in tiny seaweed bubbles and injecting them into people with type 1 diabetes could one day remove the need for daily insulin injections, an Australian researcher says.
+Professor Bernie Tuch of the University of New South Wales launched a trial of the technology this week, using capsules made from the seaweed derivative alginate and measuring just 300 micrometres across.
+Tuch says if the trial works, it will mean that insulin producing cells, or islets, can be transplanted, effectively reversing type 1 diabetes, without the need for immunosuppressive drugs.
+This is because the capsules protect the transplanted cells from being sought out and destroyed by the body's immune system.
+The capsules also contain tiny holes that let the insulin flow out while allowing oxygen and nutrients in.
+"The concept of the seaweed is that it forms a coating around the islets ... with holes that are small enough to prevent immune cells entering," Tuch says.
+The trial, involving a 51-year woman who was diagnosed with type 1 diabetes 40 years ago, is the first of its kind in Australia.
+Tuch's team at the Diabetes Transplant Unit at Sydney's Prince of Wales Hospital has previously tested the method in animals.
+An Italian group began a similar human trial two years ago but is using capsules made from a different material.
+About 75,000 capsules
+During Monday's half-hour procedure the woman was injected with 75,000 capsules containing a total of around 200,000 islet cells.
+The islets had been isolated from a cadaver and put into the capsules in a procedure Tuch compares to blowing soap bubbles.
+"There's the alginate, there's your cells and there's air," he says.
+"You blow the air and the alginate and the cells together and it's like blowing soap bubbles; they come out with the cells inside the capsules."
+The capsules were injected into the patient's abdomen where it's hoped they will start producing insulin within 24 hours, allowing her to slowly begin reducing her insulin injections. 
+Tuch says one injection could potentially last a lifetime although it's not yet known whether the current patient will need extra injections.
+What could go wrong?
+Immunologist Dr Bronwyn O'Brien, who is working with a team from the University of Technology Sydney to genetically engineer liver cells so they produce insulin, says Tuch's method is promising but may have complications.
+"In practice one of the big problems is that ... often islets that are in the centre of the capsule become hypoxic, they're not getting oxygen, and they die," she says.
+"The implications would be the cells would break up into possibly small enough pieces that could leave the capsule."
+There's also a chance that immune cells could grow around the outside of the capsules, blocking the flow of insulin, she says.
+And while the pores in the capsules are big enough to keep T cells and antibodies out, there's still a chance that cytokines, the so-called messengers of the immune system, will slip through and produce an inflammatory response.
+Tuch acknowledges this risk and says the patient received anti-inflammatory drugs as a precaution.
+"We don't anticipate there is going to be a major inflammatory response but if they do get in then the islets may be destroyed," he says.
+Not just for diabetes
+The concept of microencapsulation as a means of avoiding rejection drugs could apply to any transplant involving cells, Tuch says, and in particular stem cell therapies.
+"The concept of using capsules is certainly something that is reaching its clinical testing and time will tell what it has to offer," he says.
+
+The search for life on other planets is homing in on a handful of solar systems that resemble our own. But not everyone agrees this is the best approach
+Astronomers looking for extraterrestrial life now have a short list of places to point their telescopes. 
+They include nearby stars of the right size, age and composition to have Earth-like planets circling them, scientists say.
+But cuts in US federal funding mean that private philanthropists, who pay for the bulk of their work, may find out first when and if extraterrestrial life is discovered, the astronomers told a meeting of the American Association for the Advancement of Science. 
+Dr Margaret Turnbull of the Carnegie Institution of Washington released her top 10 list of potential stars to the meeting.
+They will be the first targets of NASA's Terrestrial Planet Finder, a system of two orbiting observatories scheduled for launch by 2020.
+"There are 400 billion stars in the galaxy, and obviously we're not going to point the Terrestrial Planet Finder ... at every one of them," says Turnbull. 
+So, on behalf of NASA and the now independently funded Search for Extraterrestrial Intelligence, or SETI, she narrowed down the list to stars that could have planets with liquid water orbiting them. 
+"We want to see these habitable planets with our own eyes," she adds. So the star cannot be too bright, or it will obscure the planet. 
+Variable stars, which grow hotter and cooler, probably would not be conducive to life, so they are thrown out, as are stars that are too young or too old. 
+Some are too gassy to have spawned planets like Earth, which contains a lot of metal. Others have massive companions whose gravity could interfere with the steady conditions needed for life to evolve. 
+Top 10 list
+Turnbull's top 10 list includes 51 Pegasus, where in 1995 Swiss astronomers spotted the first planet outside our solar system, a Jupiter-like giant. 
+Others include 18 Sco in the Scorpio constellation, which is very similar to the Sun; epsilon Indi A, a star one-tenth as bright as the Sun; and alpha Centauri B, part of the closest solar system to our own. 
+"The truth is when looking at these so-called 'habstars', habitable solar systems, it is hard to really rank them. I don't know enough about every star to say which one is the absolute best one," Turnbull says. 
+But Dr Carol Cleland of the University of Colorado argues that astronomers are limiting themselves by looking for planets that closely resemble Earth. 
+"I actually think we ought to be looking for life as we don't know it," Cleland says.
+She says life on Earth is all so similar, based on DNA made up of specific building blocks, that it is likely to have had a single origin.
+Life elsewhere may be built from different ingredients, or structured very differently, she says.
+Feeling the pinch
+Dr Jill Tarter of the SETI Institute, set up after US government funding for the program was cut, says the current budget threatens other astronomical programs.
+She says research and analysis budgets were cut by 15% in the fiscal year 2007 budget proposed this year by US President George W Bush. 
+"In the case of astrobiology, the cut is to 50% of what it was in 2005," Tarter says. "We are facing what we consider an extraordinarily difficult financial threat." 
+She says NASA once had a policy of what to do, who to call, and how to announce the news if someone detected a signal of intelligent life from space. 
+"Today it is in fact a group of very generous philanthropists who will get the call before we get a press conference," Tarter says.
+They include Microsoft co-founder Paul Allen and Microsoft chief technology officer Nathan Myhrvold.
+
+Some children with autism really can empathise with others, researchers say
+People with autism are more intelligent and able to function better than previously believed, experts say.
+But mistrust of doctors, biased tests and the internet have bred myths about the condition.
+At a meeting of the American Association for the Advancement of Science, researchers presented reports showing that even people with autism who do not speak can have above-average intelligence.
+They also offered additional studies disputing claims that vaccines can cause autism. 
+"The current figures are that 75% of autistic people are mentally retarded, with the mute the most ... impaired," says Canadian researcher Dr Laurent Mottron, an autism researcher at Montreal's H&ocirc;pital Rivi&egrave;re-des-Prairies. 
+But Mottron believes the wrong intelligence tests are used to assess autistic children.
+Many are tested using the Wechsler scale, a common IQ test that includes questions about words and concepts learned in school. 
+The Raven's Progressive Matrices test measures abstract reasoning and consistently gives autistic children higher scores, Mottron says. 
+The average boost in score is 30 points, Mottron says, enough to put someone previously considered mentally retarded into the normal range and the average to gifted status. 
+Mottron was so impressed by the abilities of one autistic student, Michelle Dawson, that he made her a co-author of some of his papers. 
+Autism is a term used to describe a broad range of symptoms, from an inability to use language normally, to exhibiting deeply disturbed and repetitive behaviours. 
+Professor Morton Gernsbacher at the University of Wisconsin-Madison questioned a common idea among autism researchers that autistic people lack a 'theory of mind'. This, among other things, gives an ability to empathise with others.
+Again, she says, the wrong tests are used to assess this ability. 
+Is there an autism epidemic
+Dr Judith Grether, a California epidemiologist, says she questions the idea that there is a new autism epidemic. 
+She says it is impossible to find out how many cases of autism there were in the past, because many people with autism were often diagnosed as retarded, or never diagnosed.
+Without that information, it is impossible to say if the number of cases has grown, she says. 
+"We have to do the studies to find the answers," she says. 
+Grether says US researchers have begun taking prenatal blood samples from pregnant women and will look for clues when and if some of their children are diagnosed with autism.
+They are examining hormones, heavy metals, immune system proteins and other factors. 
+The studies found no link with vaccines, says Dr Irving Gottesman, a psychiatrist at the University of Minnesota, but says the US Centers for Disease Control and Prevention has initiated four studies "to tie up the loose ends". 
+New studies are focusing on genetic susceptibilities. 
+Link with vaccines
+Gottesman says the studies may help to ease the fears of parents that a vaccine-autism link has been covered up. 
+But he says scientists are battling a plethora of websites devoted to the idea that mercury causes autism like http://www.safeminds.org. 
+Gernsbacher, the mother of a child with autism, says some parents may join these lobbying groups over the advice of doctors because they get "pat answers" to initial concerns about their children.
+Many may have been told that boys develop later than girls, for instance. 
+"The mistrust [of government-funded studies and of their paediatricians] may have arisen from those kind of experiences," she says.
+
+Leaves with jagged edges like these maple leaves allow better uptake of nutrients at the start of the growing season, when temperatures are cooler
+Leaves with 'toothed' edges help trees, shrubs and other plants cope with the cold, US researchers say.
+And studying leaves from ancient and existing plants could help to reveal past and present climates, they say in the current isssue of the International Journal of Plant Sciences.
+They say these climates are critical for determining periods of global warming and other profound temperature changes. 
+Dr Dana Royer, who authored the study with Dr Peter Wilf at Pennsylvania State University, says that the jagged, pointy edges on leaves are packed with xylem, a tissue that transports water and nutrients in sap.
+Most of the liquid evaporates by leaving the teeth through minuscule pores. 
+"In the springtime when leaves are just starting to leaf out, leaves with teeth are, on average, losing more water than leaves without teeth," says Royer, now an assistant professor of earth and environmental sciences at Wesleyan University. 
+"This loss of water helps pull more sap up from the roots. Thus trees with toothed leaves probably have a higher rate of sap flow early in the spring than toothless leaves.
+"This is important because it delivers nutrients to the developing leaves, helping to 'jumpstart' their photosynthetic season. As you move to colder and colder climates with shorter and shorter growing seasons, it becomes increasingly beneficial to have teeth," he adds. 
+What transpires?
+The researchers measured such moisture evaporation, or transpiration, and photosynthesis activity for leaves on 60 woody species from two regions with differing climates: Pennsylvania and North Carolina. 
+They determined that both energy-gathering activity and transpiration increased at jagged leaf edges by up to 45% during the first 30 days of the spring growing season. Leaves without teeth did not exhibit such a marked increase. 
+The scientists also found that plants native to colder climates, like those in Pennsylvania's south central York County, had toothy edges that were especially active. 
+But possessing teeth may not always be advantageous for leaves since the teeth also promote more water loss. Plants in drier regions seem to be better off if they have fewer teeth or are toothless. 
+Not everyone agrees
+Another theory, proposed by Taylor Field at Taylor University, holds that leaf teeth serve as a sort of 'release valve' that prevents too much sap from collecting in the leaf. 
+Professor Judith Totman Parrish, dean of the College of Science at the University of Idaho, says she thinks the jury is still out on why plants have leaf teeth. 
+"I think the authors have identified a very interesting problem and have made progress toward trying to answer it. As to whether this is the ultimate answer, that remains to be seen with further studies, but the authors have kicked off a promising line of research," Parrish says.
+Royer says the research is important because "we on Earth today are experiencing rapid climate change. A problem with trying to understand our current climate change is that it is an unreplicated experiment".
+
+Physicians in the Middle Ages inspected urine by holding it up to the light
+The colour of your urine can tell a lot about your health, says a researcher who's concerned that modern medicine is overlooking this time honoured diagnostic tool.
+The Australian researcher says the ancient practice of examining patients' urine could help doctors to monitor medication, pinpoint disease and in some cases avoid costly and invasive tests.
+Dr Carole Foot, an intensive care specialist at Queensland's Prince Charles Hospital, publishes a paper on what she calls the 'uroscopic rainbow' in the Postgraduate Medical Journal.
+The ancient Greeks first diagnosed the rare blood disorder porphyria by observing colourful urine and even named the illness after the Greek word for purple.
+Then in the Middle Ages, when urine analysis enjoyed its heyday, specimens were routinely examined in a matula, or urine glass, held up to the light.
+Foot says urine analysis could help today.
+She says the idea for the paper hit her after being on a ward round and discovering a number of patients had discoloured urine.
+"Here we were with these highly sophisticated monitoring devices that tell us all sorts of things about our critically ill patients and here we are doing something as old fashioned as looking at urine," she says.
+Urine in the hospital
+Foot says urine can provide information about whether patients are taking certain medications or are being over-administered.
+For example, propofol, a common sedative in critical care wards, turns urine pink if given in the right dose but green if patients are getting too much.
+"That's a signal for us to think about reducing the amount of propofol we're giving," she says.
+And the antibiotic rifampicin, used as an adjunct to other antibiotics and sometimes as a treatment for tuberculosis, turns urine and other secretions including tears, orange. This means it's being properly absorbed. 
+"If you take a sample of urine and it's orange you know the patient's taking their tablets," Foot says.
+"It certainly can be used as an agent to monitor compliance."
+ Using urine to diagnose disease
+Dark brown or tea coloured urine can indicate infection in patients who have undergone heart or valve operations because it suggests the patient is haemolysing, or breaking down red cells.
+Urine that turns black when exposed to air can also be a sign of alkaptonuria, a rare enzyme disorder that causes abnormalities of the skin and cartilages. And gout can produce pink urine.
+Foot says there are other ways of diagnosing these conditions today.
+"But what's interesting is that the way a lot of these conditions came to be diagnosed was based on ... people back in the Middle Ages noticing abnormalities in the urine."
+Using urine to rule out problems
+Looking at urine can also help to rule out serious complications.
+Foot says a GP who sees a patient with red urine may jump to conclusions about something sinister.
+This is because red urine points to bleeding and blood in the urine almost always means something abnormal.
+But a simple question could make it clear that the urine is red because a patient is menstruating.
+Eating beetroot, blackberry and rhubarb can also turn some people's urine red while blue-green urine can also be a sign a patient is drinking too much mouthwash.
+"I've seen people worked up about complex problems when they just didn't ask the patient something simple," Foot says.
+What should your urine look like?
+In a healthy person, urine ranges in colour from almost clear to bright yellow because of a pigment known as urochrome.
+But once the urochrome becomes concentrated, urine can go dark yellow or brownish, which suggests it's time for a drink.
+"It's a marker of hydration [which can] be used as a marker of whether you're drinking enough fluid, particularly in summer," Foot says.
+But urine inspection isn't always fail-proof, she says, because individual urine pH levels and genetic factors can influence whether or not certain substances discolour it.
+
+Circuit boards of the future could house smaller, more powerful chips made with existing technology
+Current chip-making technology could make computer processors even tinier and cheaper than first thought, researchers have discovered.
+Researchers at US technology firm IBM, who released their findings at a Silicon Valley technology conference, says the industry now has a reprieve from switching to more costly, unproven chip-making methods. 
+The commonly-used process of optical lithography has the potential to make chip circuitry more than a third as narrow as is standard in electronics today, according to IBM.
+This would mean a higher-density memory or higher memory capacity in a small package, the company says.
+It will be up to chip producers to invest in developing the technology, according to the company. 
+"Our goal is to push optical lithography as far as we can so the industry does not have to move to any expensive alternatives until absolutely necessary," says Robert Allen, a manager at IBM's Almaden Research Center in San  Jose. 
+"This result is the strongest evidence to date that the industry may have at least seven years of breathing room before any radical changes in chip-making techniques would be needed." 
+What's behind the push?
+The discovery that computer components can be smaller, cheaper, and higher capacity than once thought came amid a worldwide technology push toward more versatile and compact handheld devices. 
+IBM scientists have created the tiniest, high-quality line patterns ever made using deep-ultraviolet optical lithography, a technology currently used to  'print' circuits on chips. 
+The distinct and uniformly spaced ridges are just under 30 nanometres wide, IBM says.
+This is about one-third the size of the 90 nanometre features now in mass production and below the 32 nanometres that industry consensus held as the limit for optical lithography techniques, according to the researchers. 
+What's Moore's law?
+For decades, the semiconductor industry has relied on continually shrinking circuits to drive increases in the performance and function of chips and the products that use them, according to industry experts. 
+As chip features now approach the fundamental scale limits of individual atoms and molecules, the future of this trend of relentless improvement, referred to as Moore's law, is in jeopardy, IBM scientists say. 
+IBMs new result indicates that a 'high-index immersion' variant of lithography may provide a path for extending Moores law, buying the industry time.
+
+Cyclones will affect more people as coastal populations boom, according to the latest scientific statement
+Climate change can't be blamed for any of the events that made the past tropical cyclone season the worst in recent times, a report by a group of international experts says.
+"No single high impact tropical cyclone event of 2004 and 2005 can be directly attributed to global warming," it says in a report submitted to the World Meteorological Organization's (WMO) Commission for Atmospheric Sciences, which is meeting in South Africa .
+Dr John McBride is a principal research scientist at Australia's Bureau of Meteorology and reports to the WMO on the effects of climate change on tropical weather.
+He is also chair of the international WMO committee that produced the report.
+McBride says the report came as an attempt to separate fact from fiction in relation to recent controversy about the role of climate change in producing tropical cyclones.
+McBride says there's no doubt that the latest season was the most ferocious in recent times, with a series of vicious cyclones including Hurricane Katrina that devastated New Orleans.
+"These last two years were probably the most severe ... since the satellite era began [about 40 years ago]," he says.
+But he says evidence linking this to climate change is inconclusive or lacking.
+The case against climate change
+A current argument suggests that as climate change causes the seas to warm the oceans store more energy that can be harnessed by the wind to form tropical cyclones.
+But this is too simplistic, McBride says.
+"There are other conditions that are necessary to be able to tap that energy source, such as the structure of the wind systems," he says.
+McBride says there's no proof that cyclones have become more common or will become more frequent in the future, or that they'll take place in more parts of the world.
+"Worldwide, there's really no evidence for any change," he says.
+He says the report also questions claims that tropical cyclones have become more intense over the past 50 years, saying data used in the past may be inaccurate or incomplete because of limitations with the technology of the day.
+The rising damage toll
+McBride says it's true that the cost of cyclones, in terms of life and property, appears to be rising.
+But he says this is because more people are living on the coast, not because cyclones are becoming more severe.
+"There's a public perception that we're getting disasters everywhere and part of this is due to the fact that there are so many people living in vulnerable areas," he says.
+"Given no change in tropical cyclone behaviour at all you will still get an increase in insurance damage and the financial scale of damage because of increasing coastal infrastructure."
+Sea levels
+What is of concern, McBride says, is strong evidence that sea levels are rising. 
+In this way climate change may have an indirect effect on the potential for tropical cyclones to cause damage because of increasing storm surges from the sea.
+This means that even if there is no change in tropical cyclones their potential to cause death and damage will increase if sea levels rise, he says.
+
+Frogs produce a range of chemicals in their skins, including ones that smell like cashew nuts. Now scientists say some of these chemicals repel insects 
+Some Australian frogs create their own insect repellent, some resembling rotten meat and others roasted cashew nuts or thyme leaves, researchers find.
+The research team, which includes Associate Professor Mike Tyler of the University of Adelaide and entomologist Dr Craig Williams from James Cook University, publishes its findings online in the journal Biology Letters. 
+Frogs produce a number of chemicals in their skin, including hallucinogens, glues and antimicrobials, to ward off infection and stop other animals from trying to eat them.
+"We wanted to test Professor Tyler's [belief] that they should also produce an insect repellent," says Williams.
+The research team studied five species of Australian frogs, including the Australian green tree frog.
+Using massage and acupuncture techniques, they stimulated the muscles beneath the frogs' skins to produce secretions.
+"What we found was that frogs produce a variety of chemicals in their skin and these ooze out of the pores of their skin when they are stressed," says Williams. 
+The secretions, some of which repel mosquitos, have different smells depending on a number of factors such as what the frog eats.
+"The frogs produce hundreds of chemicals and one frog's smell might be made up of six or seven different chemicals, so they all smell quite different," Williams says.
+"The chemicals evaporate very quickly from the skin and it's the volatile smell that repels [the mosquitos]."
+A new mosquito repellent?
+The team found that skin secretions from an Australian green tree frog, for example, protected a mouse from mosquitos when the secretion was applied.
+The researchers say this is the first time a vertebrate has been found to have its own in-built mosquito repellent.
+But the frog secretion was not as repellent as DEET, diethyl-m-toluamide, the ingredient in most commercial mosquito sprays.
+Williams doesn't believe that a new brand of natural insect repellent will result from the research. 
+"The smell is just not very good ... some smell of rotting flesh, some of nuts, some of thyme leaves."
+Last year the frog-sniffing research team won an Ig Nobel prize for its work on skin secretions.
+The prizes honour "achievements that first make people laugh, and then make them think".
+At the time, the researchers talked about frog smells that reminded them of Bombay curry and cut grass.
+
+Most of the world's sharks live at depths that commercial trawlers can access, a new study shows
+Ocean depths beyond 2000 metres are almost devoid of sharks, a finding that is grim news for these threatened fish, a study finds. 
+An international team of researchers publishes its findings in the journal Proceedings of the Royal Society B.
+The researchers used deep-sea trawls, baited hooks and baited cameras to see where sharks live, testing depths in the Atlantic, Pacific and Indian oceans and Mediterranean Sea from 471 to 5900 metres.
+They generally saw or caught sharks at up to 2000 metres, but there were few sharks beyond this depth.
+The deepest specimen was the leafscale gulper shark, caught at 3280 metres.
+This means that there are no reserves of sharks living in the abysses, rarely-explored depths that are beyond 3000 metres that comprise 70% of the oceans' volume.
+As a result, almost all sharks are within reach of modern deep-sea trawlers, which can net fish to a depth of up to 2300 metres. 
+"Sharks are apparently confined to about 30% of the total ocean, and distribution of many species is fragmented around sea mounts, ocean ridges and ocean margins," says the paper, which mentions other chondrichthyes, a category that also includes skates and rays.
+"All populations are therefore within reach of human fisheries, and there is no hidden reserve of chondrichthyan biomass or biodiversity in the deep sea.  Sharks may be more vulnerable to over-exploitation than previously thought."
+Endangered or facing extinction
+Of the 490 species of shark, 25 are endangered or facing extinction, according to the Red List of threatened biodiversity compiled by the World Conservation Union (IUCN). 
+But this number is set to grow, in the light of new data assessed by the IUCN's group of shark experts, the Swiss-based agency says. 
+Many shark species are very slow-growing, which means that a sudden drop in numbers can threaten their survival. 
+Shark species have been ravaged by commercial trawling. They are scooped up accidentally as bycatch by trawlers hunting more lucrative fish, and are also being increasingly targeted for their fins, which are used for the Chinese  shark-fin soup, and for their liver, which is rich in oil. 
+Some species of chondrichthyan fish have adapted to the extreme pressures and poor light of the deep ocean. 
+The shark, though, seems to be excluded from life in the abysses because of a lack of food down there and the relatively high buoyancy of its liver, says the paper, by Professor Imants Priede of Scotland's University of Aberdeen.
+
+Genes that govern aspects of social communication, human bonding and spirituality help to determine whether you'll make a good dancer, research suggests
+Professional dancers are born with at least two special genes that give them a leg up on the rest of us, according to a new study.
+Recent research also has suggested that intelligence, athletic ability and musical talent are linked to our genes and brain hard-wiring. 
+With dancing added to the list, the evidence indicates that certain individuals are born with a predisposition to specific behaviours and talents, and that at least some of these qualities may represent evolved attributes. 
+"I think that dancing is an evolved trait," says Professor Richard Ebstein, who led the study, published in a recent issue of the PLoS Genetics journal.
+"Animals have courtship dances and I think that human dancing represents the further development of a very ancient animal trait," says Ebstein, a psychology professor at Hebrew University's Scheinfeld Center for Genetic Studies.
+"Also the fact that dancing is universal and existed in all human societies, even those communities of man separated geographically by tens of thousands of years [Aboriginal Australians, native Americans, Africans, Eurasians] attests to the very early origin of dance in our evolution as a species."
+First, find your dancers
+Ebstein, doctoral student Rachel Bachner-Melman and their colleagues examined the DNA of 85 currently performing dancers and their parents.
+They then did the same thing for 91 competitive athletes and 872 people who neither regularly dance nor often participate in sports. 
+The scientists discovered that dancers tend to possess variants of two genes that are involved in the transmission of information between nerve cells. 
+One of the identified genes is a transporter of serotonin, a brain transmitter that contributes to spiritual experience.
+The second is a receptor of the hormone vasopressin, which many studies suggest modulates social communication and human bonding. 
+"People are born to dance," says Ebstein. "They have [other] genes that partially contribute to musical talent, such as coordination, sense of rhythm. However, the genes we studied are more related to the emotional side of dancing - the need and ability to communicate with other people and a spiritual side to their natures that not only enable them to feel the music, but to communicate that feeling to others via dance." 
+Ebstein believes some adults may possess the special gene variants, but they perhaps never nurtured the related skills or recognised their hidden talent. 
+"Many of us surely have the ability, but for a hundred reasons never exploited that particular talent," he says.
+Ebstein explained that the identified genes seem to be linked to every form of dancing, from tap to hula, since all usually involve social communication and connecting to music or rhythms.
+Other factors to consider
+Professor Irving Gottesman, a senior fellow in psychology at the University of Minnesota and an emeritus professor from the University of Virginia, is one of the world's leading experts on genes as they relate to human behaviour and psychology. 
+Gottesman emphasises previous research has shown that genes are only one part of "complex causality" systems that make us who we are.
+For example, he confirms that intelligence can be in our genes, but that socioeconomic considerations, such as a quality education, can have a greater influence on a person's intellect. 
+Ebstein agrees that genes are not the whole story. He says those of us without a twinkle-toed predisposition can still become good dancers, since "it's not only a question of having the right genes, but also training and motivation, that make professional dancers".
+
+Scientists have been inspired by the path of a free-falling ball to work out a crucial step in quantum computing
+What can a quantum computer do? The answer is as simple as watching a ball free-falling under gravity, say Australian physicists.
+They say the maths that describes a falling ball can be used to identify algorithms for quantum computers to work on.
+Mark Dowling and colleagues at the University of Queensland report their argument in today's issue of the journal Science.
+Some problems, like finding the factors of very large numbers, are beyond the capability of normal computers, says Dowling.
+"A simple example would be 15. The factors are 3 and 5," he says. "But if I give you 256 billion nine hundred and whatever and ask you what numbers multiply to give that, that's a hard problem."
+In general, a standard computer will require 10^n steps to find the factors of a number with 'n' digits.
+This means that as a number gets bigger, the number of steps in the algorithm used to solve the problem increases exponentially and it becomes unfeasible to calculate.
+But it is expected that quantum computers will be able to solve such problems more easily, using algorithms that do not have an exponential increase in steps as the number increases.
+Quantum computers are only in their infancy right now, which is why internet commerce can rely on encryption codes based on factoring very large numbers to secure credit card details.
+But as quantum computers mature, not only will this present a challenge for those involved in internet security, researchers will also want to put these powerful computers to more useful work than cracking codes.
+Scientists have been looking for problems, like factoring, which would be suitable for a quantum computer to solve. But so far it's been a difficult task.
+Now the Queensland researchers have found a surprising way of identifying quantum computer algorithms.
+Geometric inspiration
+Dowling and colleagues were inspired by the field of mathematics called Riemannian geometry, which helps to find the shortest path between two points in a curved space.
+Picture a ball at the top of a hill in a hilly landscape about to travel from A to B.
+The quickest path would be for the ball to fall freely from A under gravity, working its way down the hill to B.
+Now imagine the hills are like steps in an algorithm. The bigger the hill, the more steps.
+There may be many possible algorithms that solve a problem, or paths to get from A to B. But the ones with the least number of steps are equivalent to the path taken by the free-falling ball.
+The researchers have found that the maths that describes the path of the free-falling ball can be used to identify algorithms suitable for quantum computer problems.
+"It's a new route to finding problems that a quantum computer can do easily," says Dowling.
+He says there are many problems that standard computers cannot solve and that may be candidates for quantum computing.
+One such problem is the 'travelling salesman problem', which identifies the shortest route for someone visiting a large number of locations.
+
+Pluto is in the centre and Charon is just below it. The new moons, P1 and P2, are to the right of Pluto and Charon
+The tiny, distant and frozen planet Pluto, for 30 years believed to have just one moon, has two more satellites, US astronomers confirm.
+They tentatively announced the discovery of the two moons last November.
+Now they've confirmed their find, after spending six months analysing images from the Hubble Space Telescope and publishing their work in today's issue of the journal Nature.
+Pluto's first known satellite Charon was not discovered until 1978. With a diameter of 1200 kilometres, it is half that of Pluto, abnormally large for a moon in relation to its planet.
+Some scientists suspected Pluto had other, tiny moons. But at such a great distance from Earth, they have been hard to spot.
+The two additional orbiting satellites, P1 and P2, are travelling outside the orbit of Charon and are tiny by comparison, say scientists led by Dr Hal Weaver of Johns Hopkins University.
+P1, the more distant of the two from Pluto, has a diameter of between 60 and 165 kilometres while P2 is 20% smaller. 
+"Although definitive orbits cannot be derived, both new satellites appear to be moving in circular orbits in the same orbital plane as Charon with orbital periods of about 38 days for P1 and 25 days for P2," they write. 
+Charon's density is also very similar to that of Pluto's, which appears to back theories that the planet whacked into a large space object, causing a large chunk to break off and eventually be enslaved as a satellite. 
+P1 and P2 may have resulted from the same collision, says Dr Alan Stern of the Southwest Research Institute in the same issue of Nature.
+First with multiple satellites
+The discovery of the two new members of Pluto's family make it the only object in the Kuiper belt, a vast region of rock and ice beyond Neptune that contains debris from the formation of the solar system, known to have multiple satellites, the scientists say.
+The scientists also expect Pluto's small moons to generate debris rings of their own, from surface impacts.
+"[This] would open up a whole new class of study because it would constitute the first ring system seen around a solid body rather than a gas giant planet," says Stern's colleague and co-author Dr Bill Merline.
+Pluto was only discovered in 1930 and because of its vast distance from Earth has remained largely enigmatic ever since. 
+It's some three billion miles from the Sun and the only planet not yet to have been visited by a spacecraft.
+NASA's New Horizons mission, which was launched earlier this year, will be the first to take a detailed look at Pluto, in 2015, and the Kuiper belt by 2020.
+
+Japanese people traditionally eat eel on the hottest days of summer to combat the heat. Seen here, restaurant owners inspecting their stock ahead of national Eel Day
+An ancient mystery surrounding the Japanese eel, a species as prized by fishermen for its high price as it is by chefs for its delicate flesh, has been explained at last. 
+Like its Atlantic cousins, the Japanese eel (Anguilla japonica) matures in freshwater but then migrates out to sea to spawn.
+But where this act is carried out has, until now, been an enigma.
+The answer, says a Japanese ocean researcher today in the journal Nature, lies in a tiny triangle of the Pacific Ocean about 2000 kilometres east of the Philippines, near underwater mountains west of the Mariana Islands.
+There male and female eels gather in the waning moonlight in the middle of the year, luxuriating in the balmy tropical waters. 
+University of Tokyo scientist Professor Katsumi Tsukamoto collected newly-hatched eels during a research trip aboard an oceanographic vessel, the Hakuho Maru, last year. 
+The creatures were still in a microscopic larval state and could only be identified with a DNA test.
+The scientist pinpointed their spawning site as 14&deg; north, 142&deg; east, to the west of the Suruga seamount in the southern part of the West Mariana Ridge.
+The eels had hatched about four days before the new moon of June 2005. 
+Just the spot
+The site is cleverly chosen, because it enables the hatchlings to be carried northwestward on the Kuroshio Current, which flows towards the coastline of China and Japan where the eels mature in rivers and lakes. 
+If the spawning were to occur only a little bit further south, the infant eels could get swept up in the Mindanao Current, which runs southwards down the eastern side of the Philippine archipelago. 
+The love grounds of the Japanese eel are tiny when compared to those of its two Atlantic relatives, the European and American eels (A. anguilla) and (A. rostrata), which reproduce in the Sargasso Sea in the eastern Caribbean.
+Grilled, steamed, grilled or baked, the eel is a delicacy in Japan, where it is known as unagi. 
+Most eels sold for food come from aquaculture. But these eels come from wild eels that are caught and put in fish farms to mature in captivity. 
+A surge in demand
+As a result of surging demand and disruption to its reproductive cycle, catches of this species have fallen by three-quarters in the past 30 years, according to the UN Food and Agriculture Organization. 
+The price of Japanese eel has soared over the past decade, prompting importers to turn to cheaper European eels to meet demand. 
+In turn, this has encouraged dangerously unsustainable catches of European elvers, known as 'glass eels' because they are transparent for the first few years of their life.
+
+Racalibration of the Earth's radiocarbon clock is changing what we know about when early humans colonised Europe
+The ancestors of modern humans moved into and across Europe, ousting the Neanderthals, faster than once thought, a new analysis of radiocarbon data shows. 
+Rather than taking some 7000 years to colonise Europe from Africa, the reinterpreted data shows the process may only have taken 5000 years.
+Professor Paul Mellars from the University of Cambridge publishes his results today in the journal Nature. 
+"The same chronological pattern points to a substantially shorter period of chronological and demographic overlap between the earliest ... modern humans and the last survivors of the preceding Neanderthal populations," the professor of prehistory and human evolution writes. 
+The reassessment is based on advances in eliminating modern carbon contamination from ancient bone fragments and recalibration of fluctuations in the pattern of the Earth's original carbon 14 content.
+University researchers have, for example, found better ways of preparing bone collagen for analysis. This involves a process of ultrafiltration, which removes contaminants with a lower molecular weight, such as organic salts and humic acids.
+And taking into account the carbon signature of deep-sea sediments and ice cores, has allowed researchers to recalibrate radiocarbon ages.
+Taking over the world
+Populations of anatomically and behaviourally modern humans first appeared in the Middle East some 45,000 years ago and slowly expanded into southeastern Europe. 
+Previously it was thought that this spread took place between 43,000 and 36,000 years ago.
+But the re-evaluated data suggests that it actually happened between 46,000 and 41,000 years ago, starting earlier and moving faster. 
+"Evidently the native Neanderthal populations of Europe succumbed much more rapidly to competition from the expanding biologically and behaviourally modern populations than previous estimates have generally assumed," Mellars writes. 
+He says the invasion could have been helped by a major change in the climate that modern man would have been technologically and culturally better equipped to deal with than the more primitive Neanderthals. 
+"There are increasing indications that over many areas of Europe, the final demise of the Neanderthal populations may have coincided with the sudden onset of very much colder and drier climatic conditions," Mellars writes. 
+"This could have delivered the coup de grace to the Neanderthals in many parts of western and central Europe in their economic and demographic competition with the incoming modern groups," he adds.
+
+Scientists have pinned down the genes responsible for the type of starch found in wheat
+Researchers are making high-fibre wheat using gene silencing technology, but hope to use old-fashioned plant breeding methods to bring it to market.
+They have used a genetic modification (GM) method known as RNA interference, or RNAi, to identify the genes responsible for high fibre.
+But rather than marketing such a GM wheat, they plan to select for plants with the right genetic make up and breed them the conventional way.
+Scientists from Australia's CSIRO and the French-based agricultural biotechnology company Biogemma UK report their findings today in the Proceedings of the National Academy of Science.
+RNAi is a way of changing the expression of particular genes in plants, says author Dr Matthew Morell, a geneticist from CSIRO's Food Futures National Research Flagship.
+The technology involves inserting a fragment of DNA into the wheat, a fragment similar to one of the plant's own DNA sequences.
+This triggers the plant's defence system to search out and destroy the resulting RNA used to make a particular enzyme.
+Usually, this enzyme would convert the starch molecule amylose to amylopectin. But if the gene that produces that enzyme is 'silenced', the wheat is higher in amylose.
+Wheat higher in amylose is harder to digest, which makes it healthier, the scientists say.
+It lowers the rate of blood sugar uptake and increases the passage of fibre into the large bowel, potentially reducing the risk of developing obesity, diabetes and bowel disease.
+There are a number of enzymes that convert amylose to amylopectin and one of the important parts of the research was to identify the critical enzyme that needed to be silenced to give wheat with high-amylose starch.
+The scientists did this by silencing a number of different enzymes in wheat, then testing the resultant starch. 
+Rat tests
+The team then fed the GM wheat to rats and compared its impact to that of standard wholemeal wheat. 
+They report that the rats fed the GM wheat had more bowel contents and a lower bowel pH, indicating better gastrointestinal health.
+The rats' faeces also had increased levels of short-chain fatty acids, which have been associated with a lower risk of colorectal cancer, the researchers say.
+And, says Morell, the high amylose content of the wheat means it is potentially another tool for managing our diet's glycaemic index or GI.
+The old-fashioned way
+The team is not developing high-amylose GM wheat. Rather, it is using the information gained in this experiment to develop an equivalent non-GM variety.
+"People, particularly in our major export markets, are still not accepting GM technology," says Morell. 
+"So the major international wheat producers - countries like Australia, the US and Canada - are not willing to risk those markets at the moment by having GM crops."
+The research so far has told the team the genes that are important in creating a high-amylose wheat. 
+This will give them a shortcut to breeding a new variety using conventional breeding methods.
+A technological shortcut
+He says the new breeding program is already well under way but the details of when the new variety will be ready are commercial-in-confidence.
+The technological shortcut, which cost several million dollars to research, will save decades in developing a high-amylose wheat variety, says Morell.
+Without RNAi, which CSIRO developed about five years ago, scientists would have had to find and combine nine different very rare mutant wheat varieties, he says.
+
+Ecstasy use has risen 70% between 1995 and 2000, says the UN
+Ecstasy, the drug that some doctors blame for depression and anxiety, may often only enhance these symptoms rather than cause them, according to a study published today. 
+Dutch researchers found that children who suffered from depression were more likely to go on to use the illegal drug when they grew up to make them feel better. 
+The appearance later in life of mental health problems in these people might not therefore be primarily due to their use of ecstasy, but could reflect pre-existing conditions. 
+"Using ecstasy may increase a risk that is already there," says Anja Huizink, assistant professor at the Erasmus Medical Center in Rotterdam, author of the study that appears in the British Medical Journal today.
+"Other studies claim that ecstasy leads to depression," Huizink says. "Sometimes that is the case. But perhaps it is more the case that individuals who already have an increased risk for depression are more likely to use ecstasy." 
+Clubbers
+Ecstasy, methylenedioxymethamphetamine or MDMA, was used in the 1970s to treat depression.
+It helps the body to relax, reduces inhibitions, increases energy and brings feelings of euphoria.
+The drug is now used by millions of young people around the world, especially clubbers who say it can help them dance all night. 
+United Nations data suggests the use of ecstasy surged by 70% between 1995 and 2000. 
+But ecstasy has increasingly been linked with health problems such as depression, especially where individuals have used the drug heavily over a long time.
+The Dutch study of 1580 individuals over 14 years left open the possibility that ecstasy might cause depression in some cases.
+"Perhaps for individuals who did not display symptoms of depression and anxiety in childhood, using a lot of ecstasy may also cause depression. We are not saying that is not the case, but we need more studies," says Huizink. 
+More than a decade later
+She and her colleagues first looked at their sample in 1983, before ecstasy appeared as a recreational drug in the Netherlands. Use of the drug was then assessed 14 years later. 
+Individuals with signs of anxiety and depression in 1983 showed an increased risk of starting to use ecstasy. 
+The researchers say other factors not tested in their study could account for some people to be more likely to use ecstasy. These included the social environment, novelty seeking and the substance use of parents. 
+"Focusing on these vulnerable individuals in future studies will increase our insight into the potential harmful effects of MDMA," they conclude. 
+For more information about ecstasy and other drugs, side-effects, and where to go for support or referral, see the DrugInfo Clearinghouse website, run by the Australian Drug Foundation.
+
+Could the explosion be a new type of gamma-ray burst?
+A new kind of cosmic explosion has been spotted in Earth's celestial neighbourhood, scientists report. 
+The blast seems like a gamma-ray burst, one of the most distant and powerful type of explosion known to astronomers. 
+But when scientists first detected it with NASA's Swift satellite on 18 February, the explosion was about 25 times closer and lasted 100 times longer than a typical gamma-ray burst. 
+"This is totally new, totally unexpected," says Dr Neil Gehrels, Swift's principal investigator.
+"This is the type of unscripted event in our nearby universe that we hoped Swift could catch." 
+The explosion originated in a star-forming galaxy about 440 million light-years away towards the constellation Aries.
+A light-year is about 10 trillion kilometres, the distance light travels in a year. 
+This would be the second-closest gamma-ray burst ever detected, if indeed it is one. 
+The burst lasted for nearly 2000 seconds, or about 33 minutes, astronomers say. Most bursts last a few milliseconds to tens of seconds.
+The burst was also surprisingly dim. 
+Scientists at Italy's National Institute for Astrophysics found hints of a budding supernova, an exploding star, when they saw the afterglow from the original explosion grow brighter in optical light. 
+If it is a supernova, scientists will have an unprecedented view of one from start to finish. 
+Scientists will attempt observations with the Hubble Space Telescope and Chandra X-ray Observatory.
+
+Nicotine, suspected to come from cigarette butts, are among many chemicals vacuumed up in dust from Sydney's roads
+Chemicals from car exhausts, asphalt and cigarette butts are covering our roads, an Australian study suggests.
+And accumulated run-off may need to be treated as toxic waste, says researcher Associate Professor James Ball of the University of Technology, Sydney.
+As well as raising environmental concerns, this finding may mean authorities will face increased clean-up costs, Ball says.
+The researchers went out onto Sydney roads with a modified vacuum cleaner to suck up samples, the first study to look at polycyclic aromatic hydrocarbons (PAHs) and nicotine in road dust.
+They found dirt blown in from many kilometres. And when the researchers analysed particles smaller than 200 micrometres in size, they identified 20 chemicals, including nicotine, plasticisers and PAHs.
+"Nobody's gone looking for these before," says Ball, who has been studying pollution on road surfaces for the past 15 years.
+Roads make up about one-fifth of the urban land area, he says, and about half the impervious surfaces.
+He says any pollutants that fall on roads can easily wash off into the stormwater system with the slightest rain. 
+Even small storms yielding 10 millimetres of rainfall can mobilise the dust, says Ball. The dust then enters the waterways, silting up creeks, ponds and wetlands.
+In the dust
+Nicotine, most likely from tossed away cigarette butts, is an alkaloid with a half-life in the environment of 30 days and can be toxic to aquatic organisms.
+PAHs come from a range of sources including vehicle exhausts, asphalt roads and fires.
+PAHs can accummulate in living tissue and some are carcinogens, says Professor Des Connell of Griffith University in Brisbane.
+"[PAHs] will be taken up by fish and accumulate in fish," he says.
+Ball also found many other previously reported pollutants in the dust, like phosphorous that leads to algal blooms.
+And he found trace amounts of heavy metals such as lead and zinc from tyres, petrol and bearings; chromium from wear and tear on car bodies, and copper from brake linings.
+"All of these are potentially hazardous," he says.
+Cleaning up
+Ball says the discovery of new pollutants on roads like PAHs has implications for authorities, which already have their hands full treating stormwater pollution.
+"It expands the number of contaminants that we have to manage," he says.
+And, he says, authorities may have to pay more attention to run-off from roads.
+Currently, says Ball, authorities are focused on the immediate risk to humans from sewage contaminating stormwater systems, and the immediate risk to waterways from nutrients.
+But, he says, the discovery of environmentally persistent chemicals in road run-off may mean areas receiving the run-off may eventually have to be treated like toxic waste.
+Ball says he received funding from the New South Wales Environment Protection Authority (now the Department of Environment and Conservation ) and the Roads and Traffic Authority for his study, which is yet to be published.
+
+This beaver-like mammal, Castorocauda lutrasimilis, would have taken a dip about 164 million years ago
+Mammals took to water 100 million years earlier than anyone thought, say scientists after the discovery of a curious beaver-like fossil in China.
+The animal lived 164 million years ago alongside dinosaurs, report US and Chinese researchers in the latest issue of the journal Science.
+It had a flat paddle-like tail and webbed feet, resembling a beaver. And it had fur and even the inner ear structure of a mammal, the scientists say.
+But it might have not gnawed trees as modern beavers do; its teeth suggest it ate fish.
+Professor Thomas Martin of the Forschungsinstitut Senckenberg in Frankfurt, Germany, says the finding shows the diversity of early mammals.
+"This exciting fossil is a further jigsaw-puzzle piece in a series of recent discoveries, demonstrating that the diversity and early evolutionary history of mammals were much more complex than perceived less than a decade ago," he writes in a commentary. 
+The fossil was found in the Middle Jurassic Jiulongshan Formation in China, a deposit rich in the fossils of dinosaurs, early insects and other creatures that dates to 164 million years ago. 
+Dr Qiang Ji and colleagues at Nanjing University in China and the Carnegie Museum of Natural History in Pittsburgh say the animal, which they named Castorocauda lutrasimilis, would have weighed just 500 grams. 
+"It is the most primitive taxon in the mammalian lineage known to have fur and has a broad, flattened, partly scaly tail analogous to that of modern beavers," they write. 
+They found remnants of fur, scales on the tail and, in between the back toes, webbing.
+
+An acidic burp can give you heartburn symptoms
+Reflux doesn't have to be extremely acidic to give you that burning feeling, a new study shows.
+In fact, burping can result in heartburn even when no liquid accompanies the gas up the oesophagus, Dutch researchers report. 
+Dr AJ Bredenoord and colleagues from St Antonius Hospital in Nieuwegein, the Netherlands, report their findings in the latest issue of the journal Gut. 
+The researchers monitored 32 patients with gastroesophageal reflux disease, or GERD, who had stopped taking their acid-suppressing medication.
+They were monitored for 24 hours using traditional pH testing as well as a technique called impedance. 
+Impedance allows researchers to evaluate how far reflux extends up from the stomach, measure the volume of reflux, and evaluate acidity with greater precision.
+"It's a completely new way of looking at reflux," Bredenoord says. 
+The acid test
+There were 1807 episodes of reflux, 203 of them causing symptoms. 
+Episodes that caused symptoms showed a larger increase in acidity within the oesophagus, more acidity, and extended further up the oesophagus. 
+The volume of reflux in heartburn-causing episodes was larger than for those that caused no symptoms, while the liquid also took longer to clear from the oesophagus. 
+Nearly 15% of reflux episodes were caused by more weakly acidic reflux material. 
+Just gas
+The researchers also identified 426 gas-only reflux episodes, 12 of which caused symptoms.
+Symptoms were more likely with gas reflux if they were accompanied by a rise in acidity. 
+"[The findings show that] if you only focus on looking at whether these symptoms are related to acid, you will certainly miss a few patients who symptoms are also related to weakly acid reflux," Bredenoord says.
+And volume of reflux, as well as its acidity, plays a role in whether it causes symptoms, he adds.
+New drugs
+He points out that some drug companies are developing medications designed to reduce the number of reflux episodes, rather than targeting acidity, as all currently available GERD drugs do.
+This could be helpful for the minority of patients whose symptoms are due to more weakly acid reflux, he says. 
+For more information on heartburn and reflux, see the consumer information section of the Gastroenterological Society of Australia website.
+
+A watchdog would monitor research to make sure it wasn't used by bioterrorists, yet would allow legitimate research to continue. But not everyone agrees this balance is possible
+A global watchdog is needed to prevent science being misused to produce biological weapons, say Canadian academics.
+"Bioterrorists require darkness to succeed," says Professor Peter Singer, director of the Joint Centre for Bioethics at the University of Toronto, which has published a report calling for global network of experts to help spot any misuses of science for biological warfare. 
+"In effect, we're calling for an IAEA of biotechnology," he adds, referring to the International Atomic Energy Authority, the global nuclear watchdog. 
+"Not with a team of IAEA-type inspectors, though, but an expanding global network of scientists." 
+The rationale behind the report, entitled DNA for peace: reconciling biodevelopment and biosecurity, is fear that there will be a crackdown on genuine scientific research in the name of biosecurity, an attempt to prevent biological warfare or deliberately created epidemics.
+"The question is how do you create a system where people are talking in such a way that you can enhance the positive use of biotechnology and protect against the misuse of them in such areas as bioterrorism," says Elizabeth Dowdeswell, co-author of the report and the former head of the UN Environment Program. 
+The scientists want the Group of Eight industrialised nations to help create the new watchdog, and they want investment in "positive applications" of biological sciences in developing countries. 
+That would include efforts to cure or prevent disease, and to alleviate poverty, they say. 
+But Dr Eike-Henner Kluge, an expert on bioethics and a professor at the University of Victoria in British Columbia, says a surveillance network is "pragmatically unrealistic".
+He questioned who would monitor and pay for the proposed body. 
+"How do you balance a possible negative threat on the one hand with a possible good on the other?" says Kluge. "This is the two-edged sword that accompanies any research."
+
+Marmoset fathers gain weight while their partners are pregnant to prepare for their role as a new dad
+Fathers of at least two primate species gradually gain weight during their mate's pregnancy, a new study has found.
+Researchers observed this classic female pregnancy symptom in common marmoset (Callithrix jacchus) and cotton-top tamarin (Saguinus oedipus) male primates.
+They published their results in a recent issue of the journal Biology Letters.
+The scientists suspect that males in most monogamous primates, including gibbons, some lemurs species and humans, also show signs of pregnancy when their mates are expecting.
+While the new study represents the first evidence for gradual weight gain in non-human primate expectant fathers, earlier research found that 11-65% of all human fathers have experienced some symptoms of pregnancy.
+The symptoms include weight gain, nausea, headaches, irritability, restlessness, backaches, colds, nervousness and hormonal changes, such as higher levels of the stress-fighting hormone cortisol and the strength-boosting hormone testosterone.
+Previously it was thought that these were just psychosomatic symptoms. But for many such dads it is likely that the changes help them to cope with the rigours of fatherhood once the baby is born.
+This is particularly important for the doting, yet squirrel-sized, marmoset and tamarin dads, whose job includes toting around their often hefty babies.
+"Males do most of the carrying of infants - usually two - once they are born," says Dr Toni Ziegler, lead author of the study.
+"The males invest highly in infant care, even losing weight while carrying these heavy, multiple infants through the trees," says Ziegler, a senior scientist at the University of Wisconsin, Madison.
+Ziegler and her team obtained monthly weight measurements for 29 male marmosets and 29 male cotton-top tamarins. Of these monkeys, nine marmosets and 11 tamarins had pregnant mates.
+The researchers determined that the expectant fathers experienced roughly a 10% increase in weight gain during their mate's pregnancy.
+The extra weight, which was not associated with copied eating habits, occurred gradually over the gestation periods, which are five months for marmosets and about six months for tamarins.
+The extra padding is not the only pregnancy symptom that scientists have identified in the monkey dads. The males apparently are so in tune with their mates that they undergo other physiological changes.
+"We have found for cotton-top tamarins, that males show hormonal changes around mid-pregnancy and these changes may help prepare them for their role in infant care," Ziegler says.
+"They also detect when their mate is going to ovulate and have an increase in testosterone a few days before she ovulates, so I think they are getting signals for the female at important reproductive events."
+Hardly surprising
+Brian Craft, lead keeper at Oakland Zoo in California, is not surprised by the findings.
+Craft says most monogamous non-human primate dads have the following daily schedule: "feed, travel, rest and then more of the same, with just a little time in between for play."
+"The weight gain could serve as a decoy for predation, but it more likely fortifies males, who have less time for foraging once the offspring are born. The changes, therefore, may benefit the entire family," he adds.
+
+The length of a particular gene controls your risk of developing depression after divorce, unemployment or illness
+More than a fifth of the population has a genetic predisposition to major depression triggered by a string of stressful life events, Australian researchers announce. 
+These events include: the loss of a parent or other significant relative; a relationship breakdown; or employment, financial, housing and health crises. 
+The study, published in the latest issue of the British Journal of Psychiatry, found a gene that controls the neurotransmitter serotonin is crucial.
+The researchers found that people with a 'short' version of the serotonin transporter gene have an 80% chance of developing clinical depression if they have three or more negative life events in a year.
+People with a 'long', or more protective, version of the gene only have a 30% risk of becoming depressed under similar circumstances.
+The study, by researchers from the University of New South Wales with affiliated research institutes and teaching hospitals, evaluated the relationship between genes and life experience from young adulthood into middle age in 127 teachers across 25 years.
+It is the first study to account for the timing of the first onset of depression across the lifespan.
+The long and the short of it
+'Short' and 'long' versions of the serotonin transporter gene 5-HTTLPR, located on chromosome 17, are created by a slight variation in the sequence of DNA.
+One version of the gene is inherited from each parent in certain combinations. According to the research, those who inherit two short versions are the most susceptible to depression.
+The study showed 21% of us have two short versions of the gene, 26% two long versions and the rest have one long and one short variant. 
+Professor Philip Mitchell, head of the university's School of Psychiatry and convenor of Brain Sciences UNSW, emphasises that this is a susceptibility or risk gene not a disease gene.
+"Having two short versions of the gene doesn't make you depressed per se; it increases the likelihood of becoming depressed if you experience stressful life events," he says.
+Identifying who's at risk
+Mitchell says the findings could help identify people at increased risk of depression and help direct resources into preventative interventions for people with the susceptible genetic make up.
+"I think this will spark off important clinical debate about when tests like this should become clinically available," he says.
+"The ethical question is not only whether this test should be made available publicly, but also who should have access to the results. We err on the side of privacy but private insurance bodies, for example, could demand the information as part of their risk assessment."
+For information about depression, including support and referral options, see Australia's national depression initiative beyondblue, or depressioNet.
+
+When Mount Tambora erupted in 1815, it killed 10,000 people instantly and buried the nearby village in volcanic debris
+Scientists are unearthing the 'Pompeii of the East', an Indonesian village buried nearly two centuries ago by the largest volcanic eruption in recorded history.
+Two years ago, a team of scientists including those from the University of Rhode Island and the Indonesian  Directorate of Volcanology and Geological Hazard Mitigation, began digging up the village of Tambora, which was buried by a volcanic eruption in 1815. 
+The excavation shows how Tambora's 10,000 residents were killed in moments by an avalanche of hot volcanic ash, rock and volcanic gas known as a pyroclastic flow. 
+The village was buried in 3 metres of volcanic debris. And in all, 117,000 people were killed.
+The eruption was the largest in recorded history, says Haraldur Sigurdsson, a University of Rhode Island professor who has studied Tambora since 1986.
+"Events of this type will occur in the future, and we should be aware of what could happen," he says. 
+The eruption of Mount Tambora on Sumbawa island blew 200 times more magma and pulverised rock into the air than Mount St Helen's in the US state of Washington in 1980, according to Sigurdsson. 
+Tambora's blast also sent sulfur dioxide 43 kilometres into the air, creating a chemical chain reaction in the atmosphere that caused a year of global cooling that made 1816 "the year without a summer". 
+Scientists located Tambora with help from a local guide, who told them that pottery fragments and human bones had been found in a gully. In the mid-2004 dig, scientists discovered an entombed house with two people inside. 
+One woman was found in the kitchen, her hand next to glass bottles that had been melted by the ash flow.
+The house, on wooden stilts with bamboo siding and a thatched roof, had been incinerated into charcoal by the fiery ash that Sigurdsson believes was at least 538&deg;C. 
+The finding is significant, Sigurdsson says, because "it means that we know that in an eruption such as that in 1815, that pyroclastic flows extend from the volcano in all directions to a distance of at least 40 kilometres radially and within that zone ... there is an extinction of all life." 
+Scientists also studied the deposits of volcanic ash and documented the size of the particles and their distance from the volcano, says Steven Carey, a University of Rhode Island professor with a background in physical volcanology. 
+The data can be plugged into computer models that will simulate volcano blasts and their potential fallout, he adds. 
+The deposits are one factor used to determine Tambora's eruption rate, or how much content was spewed out of the volcano and how quickly. That, says Sigurdsson, will determine when relatively harmless fallout turns into deadly ash flow.
+
+The Pinwheel galaxy contains one trillion stars
+The largest and most detailed image of a spiral galaxy has been released, including surprising views of its star-forming regions.
+The image is of the gigantic Pinwheel galaxy, or Messier 101, and was compiled from 51 images from the Hubble Space Telescope, with extra data from ground-based telescopes.
+The image reveals a giant spiral disc of stars, dust and gas, some 170,000 light-years across, about twice the diameter of the Milky Way.
+A high-resolution version of the image, which shows individual stars, is available on the Space Telescope Science Institute website.
+The galaxy contains about one trillion stars, about 100 billion thought to be about the same age and temperature as our Sun.
+Its spiral arms have large star-forming nubulae, star nurseries in hydrogen clouds. And bright young clusters of newborn blue stars trace out the spiral arms.
+The disc of the galaxy is so thin, the researchers say, that Hubble easily sees many more distant galaxies through it.
+The Pinwheel galaxy lies in the northern constellation the Great Bear and is about 25 million light-years from Earth.
+The light we see from the galaxy today is as it was at the beginning of the Miocene period on Earth, when mammals flourished and the mastodon first appeared, the researchers say.
+The composite image was compiled from images originally taken to study the expansion rate of the universe, star cluster formation, x-ray emissions and blue supergiant stars.
+
+Inflammation after infection with the Epstein-Barr virus might trigger temporary brain damage
+Chronic fatigue syndrome (CFS) might be caused by a temporary 'brain injury' during the early, inflammatory stages of glandular fever, according to Australian scientists.
+"We believe that parts of the brain which control perception of fatigue and pain are damaged during the acute infection phase of glandular fever," says lead researcher, Professor Andrew Lloyd from the University of New South Wales.
+The researchers, who publish their study this week in the Journal of Infectious Diseases, believe the Epstein-Barr virus, which causes glandular fever, might trigger CFS in some people. 
+While most people with glandular fever recover in several weeks, disabling symptoms including prolonged fatigue can last for at least six months, known as CFS.
+The scientists found the virus itself does not cause this ongoing fatigue but they hypothesise that a 'hit and run' brain injury does. 
+"If you're still sick several weeks after infection, it seems the symptoms aren't being driven by the activity of the virus in the body, it's happening in the brain," Lloyd says.
+The study is the first to follow patients within a few weeks of acute glandular fever infection for a year.
+It tracked 39 people including eight who were sick for at least six months, and 31 who recovered quickly.
+Levels of virus in the blood were no different in patients who recovered quickly from those whose fatigue lasted more than six months.
+"It's not the virus or an ongoing inflammatory response directed at the virus causing ongoing symptoms. But an inflammatory process in the acute illness might disturb brain function and make it stay symptomatic," Lloyd says.
+The mystery of CFS
+Lloyd says CFS affects one in 100 Australians and millions worldwide.
+It is a group of symptoms for which there is no medical or psychiatric explanation including unrefreshing sleep, muscle and joint pain, concentration and memory difficulties and prolonged fatigue.
+People with CFS are often unable to work or attend school.
+Theories about causes range from muscle and immune system to psychiatric problems, hormonal changes and the growing body of data linking infectious diseases, including glandular fever, as a trigger.
+The scientists will test their hypothesis by doing brain scans on study participants.
+For more information on CFS, see the ME/Chronic Fatigue Syndrome Association of Australia's website.
+
+Australia's new chief scientist is a long-term advocate of GM crops
+The position has been vacant for nine months. But Australia now has a new chief scientist whose appointment has been met with a spectrum of responses from unqualified support to downright disappointment.
+Dr Jim Peacock, the 68-year old former chief of CSIRO Plant Industry and head of the Australian Academy of Science, was yesterday appointed as the Prime Minister's new part-time adviser on science and technology.
+Peacock is still finalising his contract under which he will continue his role as a senior researcher at CSIRO.
+He takes up the reins from the previous chief scientist, Dr Robin Batterham, who resigned amidst claims that his advice to government was influenced by the interests of resource and energy giant Rio Tinto, a company he worked for part time.
+Peacock says he does not anticipate his dual role will result in any conflicts of interest, but some commentators say his impartiality may be questioned nevertheless.
+GM advocate?
+One issue is his ongoing support for genetic modification (GM) technology.
+"It think the integration of these [GM] technologies into our agribusiness will be essential for the future," Peacock told ABC Radio today.
+He acknowledges there are many concerns in the community about GM food and crops but hopes this will change as people understand the benefits of the technology.
+Professor Ian Lowe, head of the Australian Conservation Foundation and emeritus professor at Griffith University, says it is appropriate that a distinguished scientist has taken up the role of chief scientist but foresees problems.
+"He's been a long-standing advocate of genetic technology so he's not going to be seen as neutral in the discussions about that issue," says Lowe.
+While Labor welcomes the appointment the Greens say they are "extremely disappointed" and see Peacock's advocacy of GM as "highly divisive".
+
+In their lifetime, Western women will have four times as many periods as women from some traditional societies
+Regularly skipping menstrual periods using methods including the contraceptive pill might help reduce the risk of some gynaecological cancers, a conference will hear next week.
+Professor Ian Fraser, a professor of reproductive medicine at Australia's University of Sydney, says the fewer periods a woman has, the better.
+The modern consequences of too much menstruation include breast, ovarian and endometrial cancers, endometriosis, uterine fibroids, polycystic ovary syndrome and severe cyclical menstrual symptoms, he will tell the Human Reproductive Health Through the Ages conference in Adelaide.
+"The belief is regular menses means 'a good clean out' but having lots of periods is not a healthy process," Fraser says.
+"In our society women have many more periods than in primitive societies and each menstrual cycle leads to big swings in the ovarian hormones oestrogen and progesterone."
+Fraser says this overstimulates reproductive organs and the breasts.
+"The uterus, lining of the uterus and breasts were not designed to cope with this and it causes some cells to grow and regress each month, which means a greater chance of error in the proliferation process of abnormal cells," he says.
+"Breast cancer in our society is 100-fold greater than in primitive societies and having lots of menstrual cycles probably plays a role in that."
+He says substantial increases in the risk of endometrial cancer occurs as the uterus lining grows and regresses each month and in ovarian cancer as ovaries grow and regress during egg release.
+"My view is we probably have sufficient, strong, supportive anecdotal and suggestive evidence, although no solid long-term evidence, that for many women taking the pill or an intra-uterine device ... for extra years than they might have done for contraception may help later protect against a number of conditions."
+Fraser says present day Kalahari bushwomen have about 100 periods in a lifetime compared with Western women's 450.
+In our society, girls menstruate earlier and women have more periods before giving birth than women like the Kalahari.
+Women from traditional societies breastfeed for extended times, often conceive soon after menses return, average five to six pregnancies and have an earlier menopause, all factors that reduce the number of periods they have in a lifetime.
+
+Brain implants may turn sharks into underwater spies, says the US military
+The Pentagon is funding research into neural implants with the ultimate hope of turning sharks into 'stealth spies' capable of gliding undetected through the ocean, a report says.
+The research, outlined in this week's issue of New Scientist builds on experimental work to control animals by implanting tiny electrodes in their brain, which are then stimulated to induce a behavioural response. 
+"The Pentagon hopes to exploit sharks' natural ability to glide quietly through the water, sense delicate electrical gradients and follow chemical trails," says the report.
+"By remotely guiding the sharks' movements they hope to transform the animals into stealth spies, perhaps capable of following vessels without being spotted." 
+The project is being funded by the Pentagon Defense Advanced Research Projects Agency (DARPA).
+Scientists involved in the scheme presented their work last week at a meeting on Ocean Sciences in Honolulu, Hawaii, the report says.
+A team at Boston University has implanted electrodes into the brain of a spiny dogfish in a shallow tank. 
+The implants, controlled by a small radio transmitter, stimulate either the right or left side of a brain area dedicated to smell, causing the fish to flick around in that direction in response to the signal. 
+The next step will be to take this device outside the laboratory. Blue sharks implanted with the gadget are to be released off the coast of Florida. 
+As radio signals will not penetrate the sea, communications with the fish will be made through US Navy acoustic towers capable of sending sonar signals to a shark up to 300 kilometres away. 
+Other DARPA-funded researchers are working on using implants to record brain activity in sharks to understand which neurons are fired by scents, electrical or magnetic fields. 
+These signals help the fish to navigate and offer the reward of food, and could thus in theory be manipulated for surveillance work. 
+New Scientist says the DARPA work is controversial, but also points out that work with animal implants also has a potential benefit for medicine. 
+Understanding more about the brain's electrical signals could one day result in implants to control a prosthetic limb to overcome paralysis, the report says.
+
+Experts disagree about which of Shakespeare's portraits are real or fake and what we can tell about his health by studying them
+William Shakespeare died in pain of a rare form of cancer that deformed his left eye, according to a German academic who says she has discovered the disease in four genuine portraits of the world's most famous playwright.
+As London's National Portrait Gallery prepares to reveal in a show that only one out of six portraits of the Bard may be his exact likeness, Professor Hildegard Hammerschmidt-Hummel, from the University of Mainz, provides forensic evidence of at least four contemporary portraits of Shakespeare.
+Hammerschmidt-Hummel, who will publish in April the results of her 10-year research in the book The True Face of William Shakespeare, used forensic imaging technologies to examine nine images believed to portray the playwright.
+These technologies included the trick image differentiation technique, photogrammetry, computer montages and laser scanning.
+Four of these portraits shared 17 identical features.
+"The Chandos and Flower portrait, the Davenant bust and the Darmstadt death mask, all showed one and the same man: William Shakespeare. They depict his features in such precise detail and so true to life that they could only have been produced by an artist for whom the poet sat personally," says Hammerschmidt-Hummel.
+The portraits show a growth on the upper left eyelid and a protuberance in the nasal corner, which seems to represent three different stages of a disease.
+"At Shakespeare's time, the artists depicted their sitters realistically and accurately, absolutely true to life, including all visible signs of disease," Hammerschmidt-Hummel says.
+A team of doctors analysed the paintings and concluded that Shakespeare, who died aged 52 in 1616, most likely suffered from a rare form of cancer.
+According to ophthalmologist Dr Walter Lerche, the playwright suffered from a cancer of the tear duct known as Mikulicz's syndrome.
+A protuberance in the nasal corner of the left eye was interpreted as a small caruncular tumour.
+Dermatologist Dr Jost Metz diagnosed "a chronic, annular skin sarcoidosis", while the yellowish spots on the lower lip of the Flower portrait were interpreted as an inflammation of the oral mucous membrane indicating a debilitating systemic illness.
+"Shakespeare must have been in quite considerable pain. The deformation of the left eye was no doubt particularly distressing. It can also be assumed that the trilobate protuberance in the nasal corner of the left eye, causing a marked deviation of the eyelid margin, was experienced as a large and painful obstruction," Hammerschmidt-Hummel says.
+Her findings have stirred a controversy in England.
+The National Portrait Gallery, which conducted a four-year study of possible surviving portraits for the exhibition Searching for Shakespeare, stresses that "today we have no certain lifetime portrait of England's most famous poet and playwright".
+Hammerschmidt-Hummel's conclusion is based on a "fundamental misunderstanding" since "portraits are not, and can never be forensic evidence of likeness", the gallery says.
+Most experts, including those at the National Portrait Gallery, agree that only the Chandos painting may be a likely Shakespeare portrait.
+The terracotta Davenant bust, which has been standing for 150 years in the London gentleman's Garrick Club, has long believed to be work of the 18th century French sculptor Roubiliac.
+Hammerschmidt-Hummel traced it back to the times of Shakespeare through the diary of William Clift, curator of the Royal College of Surgeons' Hunterian Museum in London.
+She learned that Clift found the bust in 1834 near a theatre that was previously owned by Sir William Davenant, Shakespeare's godson. Davenant owned many Shakespeare mementos, including the Chandos painting.
+It's a fake
+The most controversial seems to be the Flower portrait, which the National Portrait Gallery dismissed as a fake as it featured a pigment not in use until around 1818.
+Hammerschmidt-Hummel contends that the painting is nothing more than a copy of the portrait she examined 10 years ago. The original Flowers had evidence of swelling around the eye and forehead, while the one about to go on display at the gallery does not have these features, she says.
+The Darmstadt death mask, so-called because it resides in Darmstadt Castle in Germany, has been long dismissed as a 19th century fake.
+But according to Hammerschmidt-Hummel, the features, and most of all the impression of a swelling above the left-eye, make it certain that it was taken shortly after Shakespeare's death.
+"A 3D technique of photogrammetry made visible craters of the swelling. This was really stunning evidence," Hammerschmidt-Hummel says.
+
+Bounty Bay on Pitcairn Island shows the island's typical steep rocky shoreline
+The original Polynesian community on the Pitcairn Islands died out because it lost touch with its neighbours who provided crucial resources, an Australian archaeologist says.
+Dr Marshall Weisler of the University of Queensland will discuss his research on the reliance of Pitcairn islanders on the neighbouring Mangareva or Gambier islanders at a conference in Mexico later this year.
+"[Pitcairn is] the kind of island that can only have people on it in the long run if it's being resourced from outside periodically," says Weisler, who has been studying Pitcairn since 1990.
+"It wasn't sustainable in the long run because the trading connections between the Pitcairn group and Mangareva stopped."
+The UK-governed Pitcairn Islands, are a group of four small rugged and relatively barren islands in a remote part of the western Pacific.
+Today, they are home to a handful of descendants of Fletcher Christian who led the mutiny on the Bounty in 1789.
+The two main islands in the group are Pitcairn and Henderson, which were originally settled in around 800 to 900 AD, he says, by "a couple of dozen" Polynesians from the neighbouring island of Mangareva.
+But by the time the Spanish explorer Ferdinand Queros sailed by in 1606, the islands had been abandoned.
+Surviving on Pitcairn
+Weisler spent several months at Pitcairn to work out why.
+He says archaeological evidence collected suggests early Pitcairn inhabitants ate seafood and seabirds such as the booby, and used earth ovens to cook.
+He says they put a fair bit of pressure on the islands' resources. For example, some species of land birds went extinct during the occupation.
+
+The near-Earth object known as 2004 VD17 may give Earth its closest shave, but not until 2102 when the risk of hitting the planet is one in 1000
+A space rock capable of sub-continent scale devastation has about a one in 1000 risk of colliding with Earth early next century, the highest of any known asteroid, watchers say.
+The rock, 2004 VD17, is about 500 metres long and has a mass of nearly a billion tonnes.
+If it were to hit Earth, it would deliver 10,000 megatonnes of energy, equivalent to all the world's nuclear weapons. 
+VD17 was spotted in late November 2004 and was swiftly identified as a rock that potentially crosses Earth's orbit. At the time watchers gave it one in 3000 risk of collision on 4 May 2102. 
+Further observations and calculations have prompted the risk on that day to be upgraded to "a bit less than 1 in 1000", says NASA near-Earth object (NEO) expert Dr David Morrison.
+"The risk of an impact within the next century [is] higher than that of any other known asteroid," he says, stressing however that the likelihood of a hit is small. 
+"Fortunately, it is nearly a century before the close pass from VD17. This should provide ample time to refine the orbit and, most probably, determine that the asteroid will miss the Earth." 
+VD17 was previously categorised as a grade green, which means merits careful watching, on the Torino scale of NEO hazards. But it has been upgraded to grade yellow, meaning meriting attention. 
+There are two more grades beyond this, orange or close encounter, and red or collision is certain, involving objects capable of inflicting regional or global devastation. 
+The asteroid's closest proximity to Earth on the 2102 flyby was not given by Morrison or the hazard list maintained by NASA and the US Jet Propulsion Laboratory. 
+Biggest threat?
+VD17's place at the top of the list was briefly snatched in December 2004 by a rock called 99942 Apophis. 
+Further observations, however, downgraded Apophis' risk to a one in 5000 chance of collision, making it a grade green risk. 
+Apophis, measuring 300 metres across and with a mass of less than 100 million tonnes, will fly by at a distance of 36,350 kilometres from the Earth's surface on 13 April 2029.
+This is slightly higher than the altitude of geosynchronous satellites, according to the website of the International Astronomical Union's Minor Planet Center.
+
+A floating iceberg off the Antarctic Peninsula
+Antarctica's mammoth ice sheet is in "significant decline", scientists say, probably due to climate change. 
+US researchers at the University of Colorado  at Boulder say online in the journal Science today the Antarctic ice sheet is losing up to 152 cubic kilometres of ice a year.
+"This is the first study to indicate the total mass balance of the Antarctic ice sheet is in significant decline," says Dr Isabella Velicogna, of the university's Cooperative Institute for Research in Environmental Sciences. 
+The team calculated that the ice sheet lost 152 cubic kilometres a year from April 2002 to August 2005, give or take 80 cubic kilometres.
+This is equivalent to global seas rising 0.4 millimetres a year, with a margin of error of 0.2 millimetres, the researchers say.
+The bulk of the loss is occurring in the West Antarctic ice sheet, according to Velicogna, whose team used two satellites orbiting Earth in tandem to gather data.
+These satellites estimate Earth's global gravity field. And variations in the gravity field over time were used to determine changes in Earth's mass distribution, necessary for estimating changes in mass of the Antarctic ice sheet.
+"The changes we are seeing are probably a good indicator of the changing climatic conditions there," Velicogna says. 
+The study seems to contradict the 2001 assessment by the Intergovernmental Panel on Climate Change which forecast that the Antarctic ice shelf would actually gain mass in the 21st century due to higher precipitation in a warming climate. 
+The US researchers say the IPCC estimate was based on sparse coverage of coastal areas, which would have affected the results.
+Twice the size of Australia
+As Earth's fifth largest continent, Antarctica is twice the size of Australia and contains 70% percent of Earth's fresh water resources. 
+The ice sheet is an average 1981 metres thick. 
+Research from the British Antarctic Survey suggests melting of the West Antarctic ice sheet alone would raise global sea levels by more than 6 metres.
+
+Up to 25% of a car's fuel goes on running the air-conditioning
+The average family car may one day have fans built into the seats to cool you down as you drive, suggests US government research.
+The cooled seats could also cut your fuel bill by more than 7%, say the researchers, fuel that would otherwise be used to run the car's air-conditioning.
+"Ventilated seats keep drivers and passengers cooler, so they need less air-conditioning to be comfortable," says the research team, led by John Rugh at the US Department of Energy's National Renewable Energy Laboratory.
+The researchers have been trying to reduce fuel consumption for air-conditioning in cars and trucks.
+Using a mannequin that breathes and sweats, the researchers tested the effect of a specially constructed seat, containing two fans that pull air from the seat surface and out from underneath the seat.
+Their mannequin, called ADAM (ADvanced Automotive Mannequin), together with physiological and psychological models, enabled the researchers to measure how the cool seats increases "thermal comfort" and reduces the need for air-conditioning.
+"If all passenger vehicles had ventilated seats, we estimate that there could be a 7.5% reduction in national air-conditioning fuel use," the researchers say.
+Real-world savings?
+Australian engineer, Associate Professor Eric Hu of Deakin University in Melbourne, welcomes the research.
+"Up to 25% of the engine power is used for air-conditioning purposes," says Hu, who works on reducing fuel use associated with vehicle air-conditioning.
+While the cool seats might make people feel more comfortable, he doesn't think the researchers' estimate of a 7.5% reduction in fuel consumption will make much difference in the real world.
+"Certainly savings are a good thing, but I'm not too sure you can say it's significant," he says.
+Hu says it would be easy to achieve the 7.5% savings with good seals, which would prevent the loss of cool air from windows and doors.
+And if people don't close their windows tightly, he says the 7.5% savings could easily be blown away.
+But Hu says research like this is going in the right direction.
+The amount of engine power used by air-conditioning translates to at least 25% of fuel use and 25% of emissions, Hu says. And until recently, he says, this problem has not been taken seriously.
+For example, he says air-conditioning is not considered when the fuel economy of new cars is tested in Australia.
+Driving uphill
+Hu's current research, funded by the Australian Research Council and air-conditioning company Air International, is looking at how air-conditioning affects fuel use under different driving conditions.
+For example, he has a theory that when a car full of passengers is driving uphill the engine can become overloaded and burn fuel inefficiently.
+This means air-conditioning would use even more fuel and worsen pollution.
+Hu is hoping to develop a smart energy management system for cars that could cut off air-conditioning when the car is going uphill and let it kick in when the car is going downhill.
+"We want to co-ordinate the engine load and the air-conditioning load," he says. "Currently these two systems are not talking to each other."
+
+The La Niña weather event, which brings higher rainfall to Australia, may be on its way. But the experts don't know how long it will last, or what its effects will be
+La Ni&ntilde;a may be on its way, says the UN's weather agency, an event that tends to bring above-average rainfall to Australia and parts of Southeast Asia.
+The World Meteorological Organization (WMO) says it has seen unprecedented signs pointing to La Ni&ntilde;a, which originates off the western coast of South America but can disrupt weather patterns around the globe.
+The Geneva-based agency says temperatures in the central and eastern equatorial Pacific have been between 0.5 and 1.0&deg;C below normal since the start of 2006.
+"Combined with broader tropical Pacific Ocean and atmosphere conditions, this is consistent with the early stages of a basin-wide La Ni&ntilde;a event," it says.
+"It is unprecedented in the historical record for a La Ni&ntilde;a of substantial intensity or duration to develop so early in the year." 
+La Ni&ntilde;a, which has the opposite effects to the more notorious El Ni&ntilde;o, last occurred from mid-1998 to early 2001. 
+Under La Ni&ntilde;a, the sea-surface temperature in the central and eastern tropical Pacific falls below normal.
+This typically brings far dryer weather to the southwestern US, Florida and western Latin America and above-average rainfall to Australia, Indonesia, Malaysia and the Philippines.
+But there can also be a knock-on effect much further afield, with an increase to monsoon rainfall in South Asia, unusual coolness in tropical West Africa, Southeast Africa, Japan and the Korean peninsula.
+La Ni&ntilde;a usually lasts nine to 12 months, although "some episodes may persist for as long as two years", according to the US National Oceanic and Atmospheric Administration.
+Hang on a minute
+But the WMO sounds a note of caution. 
+The build-up of this La Ni&ntilde;a is so exceptionally swift and intense that it is impossible at the moment to infer what the impact would be, and how long the phenomenon would last, it warns.
+"Most models and expert interpretations favour the event dissipating quite rapidly over the next three to six months," it says.
+"Nonetheless, neither a continuation of La Ni&ntilde;a beyond mid-year, nor the development of El Ni&ntilde;o in the second half of 2006, can be ruled out as possible outcomes from the current prevailing situation." 
+El Ni&ntilde;o, which last ran from 2002 to 2003, occurs when warm water builds up in the western tropical Pacific and creeps eastwards, again causing huge disruption to classic patterns of rainfall and wind. 
+Both El Ni&ntilde;o and La Ni&ntilde;a are naturally occurring cycles, although there is much speculation among climate scientists that human induced global warming may make them more frequent and more vicious and that this trend may have already started. 
+El Ni&ntilde;o means 'the little boy' in Spanish. Its name is attributed to fishermen off the coast of South America who noted the appearance of warmer water, often around Christmas. La Ni&ntilde;a means 'the little girl'.
+
+Golf is hard enough to play well on Earth. So how is a Russian cosmonaut going to hit a ball into the right orbit in space?
+A Russian cosmonaut plans to whack a golf ball into orbit from the International Space Station, a publicity stunt that critics say would add to the growing problem of space junk.
+Pavel Vinogradov is to take on the role of a celestial Tiger Woods under a deal between a Canadian golf club manufacturer and the cash-strapped Russian Space Agency.
+In one of three space walks planned from the International Space Station over the next six months, Vinogradov will climb aboard a special platform and swing a special gold-plated six iron and seek to enter the record books for the longest-ever golf drive. 
+If all goes well, and NASA, the prime agency in building and running the space station, approves, his ball will orbit the Earth for about four years.
+It would travel up to 3.36 billion kilometres before eventually burning up upon friction with the atmosphere. 
+"Every single record for distance in the golf industry will be shattered," says Element 21 Golf Co, the Toronto firm behind the scheme. 
+The ball will be fitted with a small radio transmitter allowing golf fans to track the ball on their home computer, says the company, which says it will give the club to charity. 
+Scientists, though, are less than gleeful. They say, in theory, it should be easy to hit the ball a huge distance.
+After all, US astronaut Alan Shepard exulted that his two historic 1971 golf shots on the Moon, where gravity is a sixth of the Earth's, went "miles and miles and miles". 
+On the space station, orbiting the Earth at a height of some 350 kilometres, gravity is negligible and friction is zero, which should make it a golfer's dream. 
+Taking a shot
+But, as experienced golfers will tell you, driving that little white ball with the right force and in the right direction is a lot harder than it seems, even on a terrestrial course. 
+The task is that much harder in a thick spacesuit, which leaves little room for a decent swing or flexing the joints. 
+The ball thus could quite easily be mis-hit and travel only a couple of metres, or be hooked or sliced and sent in entirely the wrong direction.
+As a result, it could accidentally land in the same orbital plane as the space station. Station and ball would both whizz around the planet on the same track, one after the other. 
+And what that means is a remote risk of a collision, capable of damaging or even destroying the space station, depending on the angle, velocity and site of impact.
+"There's a lot of room in space, but orbital mechanics is a wonderful thing, and things tend to come back to where you launched them from," says Dr Heiner Klinkrad, acting head of space debris at the European Space Agency. 
+"For the [space station], the most probable collision velocity in the worst-case scenario is somewhere at 10 to 11 kilometres per second," he says. 
+"This thing is certainly larger than a centimetre, which means it would certainly penetrate the shields of the space station if it hits at this speed." 
+The perfect swing
+Dr Jean-Michel Contant, secretary general of the International Academy of Astronautics, a Paris-based forum on space research, suggests that Vinogradov's boots be strapped to the platform and that he make a few practice swings on a tethered ball before doing the big drive. 
+"If safety criteria are respected, this exercise could be useful as a teaching tool for children and students and be fun for the broad public," he says. 
+"But it holds out no scientific benefits ... and if the worst-case scenario happens, it won't be fun at all." 
+Another problem is that of space junk, especially from exploded satellites and boosters, which is becoming a threat to satellites and travellers. 
+"The international recommendations are that you should not throw out unnecessary objects, and I wouldn't qualify a golf ball as a mission-related object," Klinkrad says. 
+Junk in space
+The junk region of most concern is between 900 and 1000 kilometres above Earth, where there are many navigation, communication and  weather satellites. The golf ball would be far below this height. 
+Dr Bill Ailor, a director of the Center for Orbital and Reentry Debris Studies at The Aerospace Corporation in El Segundo, California, told New Scientist magazine there are about 300 operational satellites in this low-orbit zone. 
+These could in theory be at risk from the ball as it slowly spirals towards Earth.
+"But the chance of something like that happening is probably very low," says Ailor.
+A NASA spokesperson says its engineers are vetting the planned golf drive for safety but was unable to say when this review would be completed.
+
+New Zealand fruits, like fruits of the swamp maire shown here, are rich in antioxidants, scientists are finding. This may help to explain low levels of infectious disease in pre-European Maori people
+Plants traditionally eaten by Maori people are the world's richest source of antioxidants, New Zealand scientists show.
+"Until now blueberries have been regarded as the 'king of the antioxidants', the best source of antioxidants in a Western diet and the standard by which they're measured," says Associate Professor Kevin Gould of the University of Otago.
+"But almost half the plants we tested had concentrations many times higher," says Gould, who measured levels in both native and introduced plants.
+Puha, a plant similar to watercress and still commonly eaten by Maori people, has over three times the concentration of antioxidants of blueberries, and New Zealand honeysuckle 10 times.
+But the fruit of the Syzygium maire or swamp maire tops the lot, with 18 times the concentration.
+The study, published in the New Zealand Journal of Botany, opens up several exciting avenues for further research, Gould says.
+"It may account for the low incidence of non-infectious disease in pre-European Maori. Even now Maori are less at risk from colon and rectal cancers than New Zealanders of European descent," he says.
+"But it may also reflect the way New Zealand plants are responding to global warming and other environmental stresses."
+Plants are particularly susceptible to stress from too much ultraviolet (UV) radiation; because of the hole in the ozone layer above Antarctica, New Zealand has one of the highest levels of UV radiation in the world.  
+Under stress
+All organisms produce free radicals when they are stressed. Normally the organism can deal with them by producing its own antioxidants to mop up them up. But too many antioxidants can cause damage.
+"A free radical is an unstable molecule that behaves irrationally," says Gould.
+"It's a bit like a jilted lover, bent on revenge, wanting to attack the first thing it sees. It's unstable because it's lacking an electron, or it's got too many, so it just wants to grab one from anywhere, including the tissue from your lung or your bowels."
+Finding plants with such high concentrations of antioxidants may prove doubly beneficial, the researchers say.
+They are potentially rich sources of dietary antioxidants and could provide a better understanding of how plants respond to environmental stress.
+
+The Sun's next active period could by twice as energetic as the last one
+Sun-spawned cosmic storms that can play havoc with earthly power grids and orbiting satellites could be 50% stronger in the next 11-year solar cycle than in the last one, scientists say.
+Using a new model that takes into account what happens under the Sun's surface and data about previous solar cycles, astronomers say the next cycle could start as soon as this year or as late as 2008.
+They offer no specific predictions of solar storms, but they hope to formulate early warnings that will give power companies, satellite operators and others on and around Earth a few days to prepare. 
+"This prediction of an active solar cycle suggests we're potentially looking at more communications disruptions, more satellite failures, possible disruptions of electrical grids and blackouts, more dangerous conditions for astronauts," says Dr Richard Behnke of the Upper Atmosphere Research Section at the National Science Foundation. 
+"Predicting and understanding space weather will soon be even more vital than ever before," Behnke says. 
+The prediction, roughly analogous to the early prediction of a severe hurricane season on Earth, involves the number of sunspots on the solar surface, phenomena that have been monitored for more than a century. 
+Twisted magnetic fields
+Every 11 years or so, the Sun goes through an active period, with lots of sunspots. This is important as solar storms, linked to twisted magnetic fields that can hurl out energetic particles, tend to occur near sunspots. 
+The Sun is in a relatively quiet period now, but is expected to get more active soon, scientists say.
+But scientists do not agree whether the active period will start within months, late 2006 or early 2007, or years, with the first signs in late 2007 or early 2008.
+Whenever it begins, the new forecasting method shows sunspot activity is likely to be 30-50% stronger than the last active period.
+The peak of the last cycle was in 2001, the researchers say, but the period of activity can span much of a decade.
+The strongest solar cycle in recent memory occurred in the late 1950s, when there were few satellites aloft, no astronauts in orbit and less reliance on electrical power grids than now. 
+What would happen on Earth?
+If a similarly active period occurred now, the impact would be hard to predict, according to Joseph Kunches of the National Oceanic and Atmospheric Administration's Space Environment Center in Colorado. 
+"It's pretty uncertain what would happen, which makes this work more relevant," Kunches says. 
+"What we have here is a prediction that the cycle is going to be very active, and what we need and what we're of course working on is to be able to predict individual storms with a couple days or hours in advance so the grids can take the action," Behnke says.
+
+Feeling ticklish?
+Most humans cannot tickle themselves because they anticipate their own actions, which alters their sense of perception, according to a new study.
+Since it is now believed that a breakdown in this anticipation process may underlie the delusions in schizophrenia, the finding may also lead to a better understanding of this mental disorder.
+"It's well known that you can't tickle yourself," says Associate Professor Randy Flanagan, one of the authors of the study published in the latest issue of the journal PLoS Biology.
+"One explanation is that since all the sensations are completely predictable, we do 'sensory attenuation', which reduces our touch perception," says Flanagan, a Canadian psychologist at Queen's University in Ontario.
+"If we try to deal with all the sensory information directed at us at any given time, it's overwhelming. We can't focus attention on crucial changes in our environment that aren't a function of our own motions." 
+Scientists previously speculated that we either filter out unnecessary information after the motion or sensation occurs, or that we predict our own actions.
+This would allow us to mostly ignore unnecessary sensations, such as the feel of our vocal chords while we speak, or the constant tapping of our fingers while typing at a keyboard. 
+Tap, tap
+To determine which of the two mechanisms is at work, the researchers asked 20 right-handed people to tap with one index finger on a force sensor that was sandwiched between the tapping finger and the other hand's passive index finger.
+With each finger tap, the sensor would deliver a tapping sensation to the passive finger. 
+Similar to self-tickling, the test subjects reported that the tap received by the passive finger was weak because they had anticipated the sensation.
+This occurred even when part of the force sensor was removed during surprise trials where the active finger just wound up tapping the air, while the passive finger still received the expected tap. 
+"We are constantly predicting the consequences of our actions," Flanagan says. "When we act on ourselves and on the world around us we predict in real time as we move."
+Hearing voices
+Flanagan also explains that a breakdown in this prediction process could be why people with delusional schizophrenia "hear voices" and mumble to themselves. 
+"If a healthy person murmurs to himself, he knows that he is hearing his own voice," Flanagan says.
+"Now imagine that the person has a deficit in the predictive mechanism. He murmurs and then suddenly hears murmuring but cannot label it as himself. As he tries to make sense of the alien voice, the explanation for it could be quite bizarre, such as thinking it is coming from a wall or the pavement." 
+He is not certain whether some people with schizophrenia can tickle themselves, but since their falsely alien sensations are often accompanied by feelings of fear and paranoia, it is likely that the experience would not be pleasurable. 
+Impressed
+Chris Frith, a professor of neuropsychology and deputy director of the Leopold M&uuml;ller Functional Imaging Laboratory at University College London, says he is "very impressed" by the new study. 
+Both Frith and Flanagan hope that the findings will help people with schizophrenia, which the US National Institute of Mental Health says affects around 51 million people worldwide. 
+"[We need] robust techniques for measuring the magnitude of the [prediction] breakdown. If techniques like the one described in the PLoS Biology paper can be used with patients, then this will have a major impact on diagnosis and the monitoring of the effects of treatment," Frith says.
+
+Footprints from people running away from Mount Vesuvius when it erupted nearly 4000 years ago, possibly part of a mass exodus
+Mount Vesuvius, the volcano that buried Pompeii and nearby towns in 79AD, could erupt far more violently, US and Italian volcanologists have discovered.
+Based on evidence from a powerful earlier eruption, the scientists say such an event could destroy villages and kill people as far as 25 kilometres from its summit.
+Dr Giuseppe Mastrolorenzo of the Vesuvius Observatory in Italy, Professor Michael Sheridan, of the University of Buffalo in New York, and colleagues have found compelling evidence that nearly 4000 years ago, Vesuvius produced a most devastating eruption. 
+The event, called the Avellino catastrophe, destroyed the area of present-day Naples, making Bronze Age farmers flee for their lives.
+The researchers first examined the well-preserved remains of Nola, a village about 15 kilometres northeast of the volcano.
+Digging the ash layer left by the eruption, they found evidence for "a sudden, en masse evacuation". 
+"Scenes of everyday life, frozen by the volcanic deposits, testify that people suddenly left the village: the moulds of four huts, with pottery and other objects left inside; skeletons of a dog and nine pregnant goat victims found in a cage; and footprints of adults, children, and cows filled by the first fallout pumice," the researchers write in the current issue of the Proceedings of the National Academy of Sciences. 
+One kilometre east of Nola, Mastrolorenzo's team found skeletons of a man and a woman buried under a metre of volcanic debris, a dramatic evidence of "their unlucky escape attempt and their death due to suffocation". 
+The eruption was probably preceded by a warning blast. A 36 kilometre column of ash and gas would have spewed high up into the atmosphere and then rained down, covering about 20 kilometres.
+The scientists believe that most of the 10,000 or so inhabitants of the area probably survived the eruption. Indeed, they found thousands of footprints made in the ash, all leading away from the volcano. 
+Archaeological evidence indicates that some people returned and tried to set up settlements again. 
+It was a vain attempt, as the deposit of millions of cubic metres of ash and small pumice fragments made the area uninhabitable for hundreds of years. 
+"We have got to know Vesuvius much better. Now we know that Pompeii doesn't represent the worst-case scenario anymore," says Mastrolorenzo.
+"We need to incorporate the data of this prehistoric eruption into the hazard plan. This is the most extreme scenario that could impact the city of Naples and its surroundings." 
+An eruption similar to the Avellino catastrophe today would affect an area much larger than the actual danger 'red zone', which comprises a population of about 600,000 and 18 towns squashed within about a 6 kilometre radius between the volcano and the sea.
+Indeed, at least 3 million people live within the area destroyed by the Avellino eruption.
+"[Computer modelling shows that] within a radius of at least 12 kilometres from the volcano, the impact force and sedimentation rate of the pyroclastic surge would cause total devastation and mortality, because the inferred dynamic overpressure of surge clouds would exceed even the building strength," say the researchers. 
+Some 15 kilometres away from the volcano most people would survive, though there would still be risk of suffocating from the fine dust cloud. 
+"Because a volcanic crisis can start quickly, leaving only a few weeks to months for planning, it is important to use all available data to forecast the scale of potential events," Mastrolorenzo says.
+"Catastrophes are often caused by the most extreme events." 
+A cycle of eruptions
+Vesuvius is the only active volcano on the European mainland and erupts dramatically in cycles.
+According to Sheridan, while there may not be a high probability that events like the Avellino eruption or the Pompeii eruption will occur in the near future, Italian authorities must still consider those possibilities.
+"There was this Bronze Age eruption about 4000 years ago, and then 2000 years ago there was the 79AD event. It seems that just about every 2000 years, there's been a major eruption of this scale at Vesuvius," says Sheridan. 
+"Using a standard statistical test, there is more than a 50% chance that a violent eruption will happen at Vesuvius next year. With each year that goes by, the statistical probability increases," he says.
+
+Do you metabolise caffeine quickly or slowly? The answer could tell you about your risk of having a heart attack
+A gene that controls how fast your body breaks down caffeine might explain why some people can get away with drinking lots of coffee and others can't, new research suggests.
+People with a genetic variation linked with slow caffeine metabolism are more likely to have a nonfatal heart attack, the researchers write today in the Journal of the American Medical Association. 
+The researchers looked at 4024 people who lived in coffee-rich Costa Rica between 1994 and 2004. Half had had a nonfatal heart attack, and half had not. 
+They found that slightly more than half had the slow version of the gene while the others had the fast form.
+"We found in individuals who had the slow version of this gene, as little as two cups of coffee a day is associated with an increased risk of heart disease," says study author Dr Ahmed El-Sohemy of the University of Toronto. 
+For those with the slow-acting gene, two to three cups of coffee a day increased their odds of a heart attack by 36%, and four or more cups a day increased the risk by 64%, the study says.
+"For those who had the fast version of the gene, there was no increased risk, even with four or more cups a day," he says.
+"Surprisingly, what we found was that in individuals under 50 years of age who were fast metabolisers ... consumption of as little as one to three cups a day was associated with a lower risk of heart disease." 
+Those with the fast-acting gene who drank two to three cups of coffee a day had 22% reduced odds of having a heart attack, but drinking four or more cups a day lessened the risk by 1%, the study found. 
+"Initially we thought that individuals who had the slow version of this gene might drink less caffeine because it stays in their system longer," El-Sohemy says.
+"But what we found is that regardless of the version of the gene that the person had, it did not affect how much caffeine they consumed." 
+Breaking down caffeine in the liver
+The enzyme cytochrome P450 1A2 is responsible for metabolising caffeine in the liver. And variations of the gene for this enzyme can slow down or speed up caffeine metabolism.
+"An individual cannot predict whether or not they have the slow or fast version of the gene, because although they can feel the effects of caffeine on the nervous system, they cannot feel the effects on their blood vessels," El-Sohemy says. 
+Since tests to determine which form of the gene you carry are not readily available and you cannot feel how fast your body is getting rid of caffeine, the study's authors recommended reining in coffee consumption to no more than four cups a day.
+Previous studies have offered conflicting findings about the health effects of coffee, and El-Sohemy notes other chemicals in coffee may play a role. 
+ "Of all the studies that have been conducted to date that looked at the effects of either coffee or caffeine on heart disease, none of them have taken into account genetic differences in the ability to break down caffeine," El-Sohemy says.
+"We are approaching the era of personalised dietary advice."
+
+Are you looking at me?
+More Australian racehorses have vision-threatening eye disease than expected, a new study shows.
+About one in 13 thoroughbred horses examined may be in danger of losing their sight.
+Cataracts, corneal scarring and lesions are among the serious conditions that two veterinarians report in the latest issue of the journal Veterinary Ophthalmology.
+Dr Simon Hurn and colleague Dr Andrew Turner say there is a perception in the racing industry that eye disease in horses is not very common.
+But they had noticed a higher than acceptable level of eye disease in performance horses and were concerned.
+When they couldn't find data to compare what they had found, they decided to carry out their own research.
+They conducted ophthalmic examinations on 204 flat-racing and jump-racing horses at four metropolitan and two country racing stable complexes in Victoria.
+They found potential vision-threatening eye disease in 7.4% of the horses and non-vision threatening disease in 57.4%.
+Generally horses' eyesight is on par with that of humans, the researchers say.
+"They probably don't have the same colour spectral type vision that we have but they do see colour and they do see movement. And because they move at speed, we can also assume they have good visual acuity [sharpness] as well," says Hurn.
+He adds that many of the eye findings were 'incidental' and wouldn't affect horses' vision.
+"Horses don't have to read newspapers or drive cars. Most of their time is spent eating or watching out for what they think are predators," he says.
+"They can do that just fine with that vision that they have and the reason they don't have the same type of colour vision that we have is that they just don't need it. Their eyesight is [good] for their environment."
+Hurn says while there may well be a genetic component to the eye diseases in general, he also believes vets are getting better at diagnosing eye disease.
+"We noticed a higher than normal incidence of cataracts in the population of horses, [however] and this could certainly have a genetic component," he says.
+
+Existing remote telecommunication networks are struggling to cope with today's internet traffic, according to one expert. So how about a new de-centralised network?
+Remote communities could access cheaper wireless broadband services than their city cousins via new-generation mobile phones and computers, say Australian researchers.
+The devices could also be part of local community telecommunication networks independent of major centralised networks, the researchers add.
+Dr Mehran Abolhasan of the University of Wollongong is heading a team that will trial the new technology in a remote Western Australian community later this year.
+"Remote communities still rely on outdated technologies and very low-capacity networks that are not really able to provide today's internet traffic," says Abolhasan, a telecommunications and computer engineering expert.
+One of the main reasons for this is the enormous cost of rolling out links to the latest communications hubs in the cities.
+And the low population in remote areas means the return on investment is quite low.
+So despite government subsidies, in Australia for example, remote communities have to pay more to get access to telecommunications than people in the city and they are often the least likely to be able to afford it.
+Ad hoc networks
+Abolhasan hopes he has a low-cost alternative to providing up-to-date telecommunications to remote communities.
+His team is developing new software and hardware that can run what are called ad hoc networks.
+The key components of the networks are small portable computer devices, such as PCs or mobile phones that can transmit as well as receive microwave signals.
+Their ability to transmit means that, as well as being a PC or mobile phone, the devices can act as nodes in a communication network.
+And if they are put on top of towers they can transmit messages over long distances, especially when a number of them are linked in a chain.
+Ad hoc networking is cheap because of the low cost of the technology that enables wireless communication between different units, says Abolhasan, and because much of the open source software is already freely available.
+"[Remote] communities would have access to a broadband-type service for a very low price," he says, "cheaper than current broadband services in the city."  
+He says ad hoc networks have another advantage because they are not centralised and if devices break down they can communicate with other units and re-route messages.
+Extending existing networks
+Abolhasan says ad hoc networking can extend the range of existing infrastructure.
+For example, if a remote community has a central building with access to a satellite network, it can extend the satellite network to individual homes.
+The technology could also be used to enable communications within a community. For example people could run their own broadband television station from the local community centre.
+"You can have a community private network without going through any infrastructure," says Abolhasan.
+The main research challenge is to increase the capacity of the technology, which at the moment is unable to service large numbers of people at the same time, he says.
+The team plans to trial ad hoc networking in an Indigenous community in Western Australia in the second half of this year.
+"If it works in outback Australia, it should work just about anywhere," says Abolhasan.
+He says ad hoc networks don't need much power and could run on solar power. He expects the technology to be available in the next three to five years.
+The project is funded by the Desert Knowledge Co-operative Research Centre in Alice Springs.
+
+Carbon dating is shedding new light on ancient scrolls and what they tell us about the history of Buddhism
+Rare manuscripts dubbed the 'Dead Sea Scrolls of Buddhism' are indeed from the 1st and 5th centuries AD, carbon dating shows.
+The manuscripts, which were written on fragile birch bark, provide an important insight into the development of Buddhist literature and help fill the gaps in some areas of Buddhist history.
+Buddhism was traditionally a spoken tradition and until now, little has been known about how it developed from the spoken to the written word.
+While Buddhism flourished throughout Asia, it disappeared from India, Central Asia and the Indonesian archipelago, taking with it many literary traditions.
+"When we first learnt about these manuscripts we looked at the scripts and the language and made a rough estimate of their approximate age," says Dr Mark Allon, from the University of Sydney, an Australian researcher who is translating the text.
+Carbon dating, conducted by researchers from the Australian Nuclear Science and Technology Organisation, confirmed the assessment.
+The scientists used the process of accelerator mass spectrometry to radiocarbon date the bark on which the manuscipts were written.
+This process counts the rare carbon-14 isotopes in a sample and uses this to calculate the sample's approximate age based on the radioactive decay over time.
+Two manuscripts from the Senior collection, which is named after the scrolls' British owner, date to between 130 and 250AD 
+And three manuscripts from the Sch&oslash;yen text, named after the scrolls' Norwegian owner, date to between the 1st and 5th century AD.
+Allon says the Senior collection dating is particularly important because it makes a major contribution to Indian Buddhism chronology.
+"One of the manuscripts we studied was found in a pot with an inscription on it indicating that it was donated in the year 12. While it didn't say what era that was, the characteristics of the inscription tell us that it must refer to the Kanishka era."
+Kanishka was a very important king in northern India in about the 1st or 2nd century AD, but the dates he lived and ruled have been debated for a century or more. 
+"What the carbon dates told us was that the earlier date favoured by some scholars, namely 78AD, is no longer tenable because the carbon dates tell us that the manuscripts actually dated from 130AD to 250AD." 
+The manuscripts are believed to have originated from Afghanistan and are among many archaeological artefacts that were sold on the international market in times of war.
+
+Gamma-ray bursts like this are among the few things energetic enough to be seen from such a distance
+The discovery of the most distance and ancient stellar explosion has now been confirmed and pushed back another 100 million light-years to 12.8 billion light-years away. 
+The explosion, known as GRB 050904, took place when the universe was a relatively youthful 900 million years old. 
+The fatal stellar scream, beamed from a giant star as it collapsed to make a black hole, contains direct clues to what the universe was like so long ago. 
+A gamma-ray burst, or GRB, is one of the few things in the universe bright enough to be seen so long and far away. 
+Three separate international teams of astronomers, including observations from Australia's Mount Stromlo and Siding Spring Observatories, describe the GRB in the journal Nature today. 
+Among them is Assistant Professor Daniel Reichart of the University of North Carolina at Chapel Hill.
+He began to suspect his team was seeing something unusual when the researchers detected the afterglow of the blast in infrared light, but could not see it in visible light, as is normally the case.
+The gamma rays were initially detected from the space-borne Swift telescope and burst detector. The rest of the observations were made from earthbound telescopes. 
+"At that point we either had found the most distant burst in the universe, or there was dust in the way," Reichart says. 
+Could it be dust?
+A careful analysis of just which wavelengths of light were missing from GRB 050904 made it clear dust was not the culprit, he explains. 
+"Dust scatters blue light out, but it's much more gradual," says Reichart. 
+GRB 050904's bluer light drops off very suddenly. That's the signature of the light having been stretched out, essentially making it redder (called redshift), over billions of years of travel through an expanding universe. 
+In a way, it's the wavelengths of light that didn't make it across time and space that pegged GRB 050904 as the oldest and furthest star ever seen.
+But the light that did survive the journey has a lot to offer as well.
+"Its attraction lies in what it can reveal about star formation early in the history of the universe," says astrophysicist Dr Enrico Ramirez-Ruiz of the Institute for Advanced Study in Princeton, who writes about the importance of the discovery in the same issue of Nature.
+Because all light, when broken into a spectrum, carries essentially a bar code of the elements that created or influenced it, the light from GRB 050904 could reveal a lot about where and when heavy elements become more common in the early universe. 
+"Distant galaxies are themselves difficult to study because they appear faint and small," Ramirez-Ruiz explains.
+"GRBs will serve not only as signposts to such galaxies, but could be used to study the gradual build-up of heavy elements in them to determine the conversion history of primordial gas into stars." 
+The first generation of stars in the universe was made of hydrogen and helium alone. Heavier elements are made by the most massive stars when they die.
+Even at the colossal distance of 12.8 billion light-years, GRB 050904 is not quite old enough to be among the first generation of stars, say astronomers. 
+That's because large stars that can create GRBs have relatively short lifespans.
+Our Sun, in contrast, is a medium-sized star which, at about 4.5 billion years old, is only middle-aged for its kind.
+
+Snuppy, on the right, with the three-year-old male Afghan hound whose somatic skin cells were used to clone him
+Two DNA tests have backed claims by disgraced South Korean scientist Professor Hwang Woo-Suk that he made the world's first cloned dog, Snuppy.
+The investigations are published today by the journal Nature, which printed the original research last August, five months before Hwang was exposed as a fraud for his work in stem cells. 
+Snuppy, short for Seoul National University puppy, initially stirred admiration among scientists as dogs are among the trickiest of animals to clone.
+But this feeling quickly ceded to suspicion when the stem cell scandal broke. 
+One of the inquiries was conducted by a panel at the university, where Hwang carried out the work at the College of Veterinary Medicine, Nature says.
+The panel had already announced in January that Snuppy is believed to be a genuine clone.
+This investigation was then double-checked by genome specialists led by Dr Elaine Ostrander at the US National Institutes of Health, using samples provided  by the Seoul team.
+The two investigations entailed making a DNA fingerprint of Snuppy, looking notably for microsatellites, telltale markers on the genome.
+They then compared microsatellites between the puppy and his genetic donor, a three-year-old Afghan hound named Tai; the surrogate mother, a yellow Labrador retriever; the unidentified donor of the egg; and other pedigree dogs. 
+Perfect match
+The tests showed a perfect match between Snuppy and Tai, confirming that Snuppy was created by placing Tai's DNA in the empty donated egg, the scientists say. 
+"It is highly unlikely that Snuppy came either from extreme inbreeding or from ... twinning," says the Seoul panel. "It is virtually certain that Snuppy was generated from somatic-cell nuclear transfer, as claimed." 
+Somatic-cell nuclear transfer entails taking an egg and removing the nucleus, which is then replaced by the nucleus of an adult cell taken from the animal to be cloned.
+The reconstructed egg is then given a jolt of electricity or treated to a chemical cocktail to make it divide, and placed in a bath of nurturing chemicals to continue growing.
+The embryo is then placed in the uterus of a surrogate mother, which if all goes well brings it to term. 
+This technique was used for the first cloned mammal, Dolly the sheep, in 1997, and has been used on a dozen other species since then. 
+Dogs, though, have been a big challenge because it is hard to acquire mature canine eggs. 
+In contrast to other mammals, dogs ovulate when their eggs are immature. The eggs then go to a special duct to mature for two or three days. 
+Hwang's team cracked this problem by gently flushing out the oviduct to recover the mature eggs. The technique could be useful for conservationists who want to preserve rare species whose eggs are difficult to harvest, scientists say. 
+In trouble with stem cells
+Hwang, 52, astonished gene scientists last May when he claimed to have created 11 lines of stem cells that were identical to the DNA of their donors. 
+But Hwang plunged into disgrace when it was discovered that this research, published in the journal Science, was fabricated.
+Similar accusations surround a 2004 Science paper in which he claimed to have produced a stem cell from a cloned human embryo.
+
+Professor Rusi Taleyarkhan with his tabletop device that he says delivers cold fusion with bubbles
+A scientist who says he has achieved 'cold fusion' using sound waves to make bubbles is being investigated by his current university after complaints from colleagues.
+Nuclear engineer Professor Rusi Taleyarkhan's work has been controversial since he published a study in 2002 claiming to have achieved the Holy Grail of energy production, nuclear fusion at room temperature. 
+If scientists can duplicate the results and harness the technology, which is based on the process that powers the Sun, tabletop fusion has the potential to provide an almost limitless source of cheap energy. 
+Many labs are working frantically to try to do so, but their efforts are difficult to substantiate and especially susceptible to being labelled as fraud. 
+Taleyarkhan, whose study was published while he was at the US Department of Energy's Oak Ridge National Laboratory in Tennessee, now works at Purdue University in Indiana and has also been trying to replicate his earlier findings. 
+He says he did this in 2004. 
+Purdue provost Sally Mason says her office is checking complaints from some of Taleyarkhan's co-workers. 
+"Purdue last week initiated a review of this research and these allegations," Mason says. 
+"The research claims involved are very significant and the concerns expressed are extremely serious. Purdue will explore all aspects of the situation thoroughly and announce the results at the appropriate time," she adds. 
+"To ensure objectivity, the review is being conducted by Purdue's Office of the Vice President for Research, which is separate from the College of Engineering." 
+Something amiss?
+The journal Nature reports today it has interviewed several of Taleyarkhan's colleagues who suspect something is amiss. 
+"Faculty members Lefteri Tsoukalas and Tatjana Jevremovic, along with several others who do not wish to be named, say that since Taleyarkhan began working at Purdue, he has removed the equipment with which they were trying to replicate his work, claimed as 'positive' experimental runs for which they never saw the raw data, and opposed the publication of their own negative results," according to Nature. 
+"In addition, Brian Naranjo at the University of California, Los Angeles, is submitting to Physical Review Letters an analysis of Taleyarkhan's recently published data that strongly suggests he has detected not fusion, but a standard lab source of radioactivity." 
+Naranjo's lab reported in April 2005 that it had achieved cold fusion by heating a lithium crystal soaked in deuterium gas. 
+Engineers and physicists have been cautious about Taleyarkhan's technique but say in theory it could work. 
+In the original report
+In his original report, published in the journal Science in 2002, Talayarkhan and colleagues say they created nuclear fusion in a beaker of chemically altered acetone by bombarding it with neutrons and then sound waves to make bubbles. 
+When the bubbles burst, the researchers say they detected fusion energy. 
+The 2004 experiment used uranyl nitrate, a salt of natural uranium. 
+Experts have been especially sceptical about cold fusion claims since Britons Professor Martin Fleischmann and Stanley Pons of the University of Southampton held a news conference in 1989 to claim they had achieved it. 
+Fleischmann and Pons were ridiculed when no-one could duplicate their efforts.
+
+A new type of tourism is taking off
+People with diabetes are flying to a clinic in Mexico for an injection of pig cells, hoping this xenotransplant will cure them.
+But experts are worried about the risks involved with this so-called xenotourism or xenotravel, both to the patient and to the rest of the community.
+Peta Cook, a PhD student at Queensland University of Technology's Centre for Social Change Research will present her research on xenotourism at a meeting of the Transplantation Society of Australia and New Zealand in Canberra later this month.
+Xenotourism is where someone specifically goes to another country for a xenotransplant, the transplant of animal tissue or organs to treat conditions like diabetes.
+Australia currently bans xenotransplantation, mainly because it could transfer infectious diseases from animals to humans.
+In other countries, such as the US, clinical trials are being carried out under strict regulation.
+But xenotransplants are available today to the general public for over US$35,000 (A$47,000).
+The Laboratorio de Xenotransplantes in Mexico has been offering pig cell transplants to the world since 2004 to treat diabetes.
+Cook says her correspondence with the clinic confirms patients from a country in the northern hemisphere were admitted in 2005.
+"They confirmed with me that there were two people who had already received the therapy in January and February last year and since returned to their home country and they had two more people who were coming across to have a consultation," Cook says.
+"They were looking at doing about one a month as an international patient but of course that could be stepped up."
+Experts urge caution
+The International Xenotransplantation Association (IXA) says xenotransplantation might introduce new infections from animals, so requires "extreme caution".
+The clinic in Mexico states on its website that its pigs are raised in "pathogen free farms" and the "isolated cells are examined to establish the levels of purity, viability, functionality, sterility and then cultured before being transplanted".
+The risk of infection is "extremely low", it states, adding it has been authorised by a range of Mexican government institutions.
+But the international expert community is concerned there's no way of checking what Mexico is doing.
+"They claim that they have approval from local and government authorities for this activity but there is no formal regulatory authority," says Professor Anthony d'Apice of St Vincent's Hospital in Melbourne, who is IXA's immediate past president.
+IXA and WHO are calling for the establishment of international standards on which animals can be used for xenotransplants and which tests should be carried out to ensure infection doesn't occur.
+They also say patients given xenotransplants need to be monitored closely to see if they get sick afterwards.
+While the clinic in Mexico requires patients to visit their GP and endocrinologists in their home country, other experts say this is not enough.
+D'Apice says infectious diseases experts should be involved in the monitoring.
+Under the quarantine radar
+Normally if you bring live animal material into Australia it has to go through quarantine. But when the animal material is inside someone, it's not exactly obvious.
+"There is no quarantine status that says you must declare that you've had a porcine transplant," says d'Apice, whose research involves genetically modifying pigs to stop rejection of their pancreas and kidney cells when they are transplanted into non-human primates.
+"If you go from the United States, down to Mexico, have a transplant, and fly back into the United States you don't tick on your immigration, quarantine or any other form that you've been potentially exposed to this type of risk.
+"I think we place ourself at some risk from xenotourism."
+While he is short on recommendations on what Australia should do about this, he says Australia should help lobby at the international level for uniform standards.
+But Cook says we can't wait for international standards because xenotourism is already happening. 
+She says Australia should address the issue now, despite its moratorium, which d'Apice predicts will be lifted in just two or three years.
+The problem is, though few people, even in the expert community, are even aware that xenotourism is happening, says Cook, least of all GPs who would be on the frontline of any fallout from xenotourism.
+"If I get a xenotransplant I could walk in to my doctor and have a sore throat and just be diagnosed with a sore throat and be told to suck on some lozenges when if fact I could have something a lot more serious going on," she says. 
+D'Apice agrees this could be a problem.
+"A GP would have absolutely no idea about this," he says.
+The Royal Australian College of General Practitioners was unavailable for comment.
+
+Sitting in cramped conditions on a long-haul flight isn't the main risk factor for DVT, researchers say. The cabin air quality may be to blame
+Low cabin air pressure and poor oxygenation enhance the risk of deep-vein thrombosis (DVT) in susceptible passengers, a study suggests.
+Until now, DVT has been most widely associated with remaining inactive for long periods, like in the cramped conditions of an aircraft cabin.
+But a study in today's issue of The Lancet journal suggests there may be additional risk factors.
+DVT occurs when a clot forms in leg veins during periods of sedentary activity. The clot can then migrate to the heart, lung or brain, sometimes days or weeks later, and inflict a heart attack or stroke. 
+Even though the phenomenon has been known since World War II, it has in recent years become a major issue for the airline industry, through lawsuits in which people who have had DVT place the blame on cramped economy seating in long flights.
+The airlines retort that DVT can occur long after a flight, which thus makes it impossible to establish a link, and point out that clotting can occur in other forms of sedentary activity, even from sitting and reading a book. 
+The latest research puts the ball back into the airlines' court, pointing the finger at cabin air quality as a potential risk factor. 
+A team led by Professor Frits Rosendaal of Leiden University Medical Center in the Netherlands, monitored levels of a key clotting protein called thrombin-antithrombin (TAT) complex among 71 healthy men and women aged 20-39. 
+A total of 40% of the people in the study were selected as they took the contraceptive pill, had a gene variation called factor V Leiden, or both, conditions which greatly increase the risk of blood clotting. 
+Up, up and away
+The volunteers were taken onboard a specially-chartered Boeing 757 for a non-stop eight-hour flight.
+It cruised at around 11,000 metres with a cabin pressure that corresponds to an altitude of 1800-2100 metres. 
+Blood samples were taken before, during and after the flight. 
+A couple of weeks later, the same group underwent the same tests, but this time at a movie marathon, watching comedy and action films for eight hours. 
+They were not allowed to drink alcohol, take aspirin or wear elastic stockings during the flight or the movies, and were asked to remain seated as much as possible. 
+The group was monitored for the final time during eight hours of regular daily activity. 
+After the flight, the concentration of TAT complex rose by about 30% on average across the group. It fell by about 2% after the cinema, and by almost 8% after the 'daily life' experiment. 
+The post-flight rise was overwhelmingly concentrated in just 11 of the 71 individuals, especially those who took oral contraceptives and also had factor V Leiden. 
+The findings suggest that "flight-associated factors" are the cause behind increased clot formation after a long trip, say the team, which conducted the study for the WHO.
+The researchers put the ring of suspicion around hypobaric hypoxia, a combination of low cabin pressure and a low oxygen level compared with terrestrial air conditions. 
+Who's most at risk?
+The data also provides a useful pointer for medical help to those most at risk. 
+There already exists an array of simple techniques or over-the-counter drugs for combatting DVT. 
+These include cutting out alcohol on a flight, stretching one's legs, taking an aspirin and wearing compressive stockings that improve blood circulation. 
+There is also a powerful anti-clotting prescription drug called heparin. 
+This medication has side-effects, which means it should be targeted at those most at risk, such as women on the pill and with factor V Leiden, cancer patients and recent surgery patients, says Dr Hans Stricker, a doctor at the Charity Hospital in Locarno, Switzerland, in a commentary. 
+Previous studies have found a two-to-fourfold risk of DVT after air travel, while a study in 2003 estimated that DVT may occur among one in every 100 frequent long-haul air travellers, in business class as well as economy.
+
+Plumes of icy material shoot out from the moon's south pole
+One of Saturn's moons, Enceladus, is spewing out a giant plume of water vapour that is probably feeding one of the planet's rings, scientists say.
+The findings, published in the journal Science, suggest that tiny Enceladus could have a liquid ocean under its icy surface which in theory could sustain primitive life, similar to Jupiter's moon Europa.
+The plume was spotted by Cassini, a joint US-European spacecraft that is visiting Saturn.
+"We realise that this is a radical conclusion, that we may have evidence for liquid water within a body so small and so cold," says Dr Carolyn Porco, Cassini imaging team leader at the Space Science Institute in Boulder, Colorado. 
+"However, if we are right, we have significantly broadened the diversity of solar system environments where we might possibly have conditions suitable for living organisms."
+Scientists have long known that many of Saturn's moons have water. They took an especially close look at Enceladus because it seemed to have a smooth surface, suggesting recent geological activity that, in turn, could mean liquid water. 
+Liquid water is a key requirement for life. Several moons have been found to have evidence of liquid water and the chemical elements needed to make life, including Europa. 
+Gigantic geyser
+But scientists are far more intrigued by the plume itself, a gigantic geyser of water vapour and tiny ice particles. 
+"It's basically this giant plume of gas coming out of the south pole of Enceladus," says Dr Candy Hansen of NASA's Jet Propulsion Laboratory in California.
+"The plume is half the size of the moon. It's huge," says Hansen, a planetary scientist.
+"Water is being spewed out of this moon. It solves some real mysteries that we have been struggling with over the years." 
+Indirect observations have shown the moon, discovered in 1789 by William Herschel, is rich in oxygen and hydrogen. But whether this is because of water is not clear. 
+Both water vapour and water particles were observed, as well as a smattering of other compounds such as methane and carbon dioxide, the international team of scientists reports in a series of papers in Science. 
+It is possible the plume comes directly from ice, but more likely there is a liquid source, the researchers say. It would have to be under the moon's surface, which is covered with ice. 
+"If a wet domain exists at the bottom of Enceladus' icy crust, like a miniature Europan ocean, Cassini may help to confirm it," Dr Jeffrey Kargel of the University of Arizona at Tucson writes in a commentary.
+"Might it be a habitat? Cassini cannot answer this question," Kargel adds. 
+"Any life that existed could not be luxuriant and would have to deal with low temperatures, feeble metabolic energy, and perhaps a severe chemical environment. Nevertheless, we cannot discount the possibility that Enceladus might be life's distant outpost." 
+Hansen is cautious. 
+"I think the best you can say is there is biological potential. We have liquid water probably, and it is in contact with rocks so there are minerals," she says.
+"And there is energy. But we haven't detected life." 
+The findings help to confirm theories that Enceladus was the source of Saturn's outer E-ring, the researchers say. 
+Saturn has at least 47 known moons. Enceladus is named after a Titan in Greek mythology who was defeated in battle and buried under Mount Etna by the goddess Athena.
+
+The new technology allows online gamers to talk and listen to others in a crowd
+Online gaming characters will one-day have more realistic voices, say researchers who are working on a system that makes nearby characters sound louder than distant ones.
+The Australian researchers say their technology will also make other forms of communication in the virtual world - whether for work, study or play - more like real life.
+Dr Paul Boustead from the University of Wollongong says this technology will be useful in the gaming world, where players generally communicate by typing text to each other.
+Typing is quite demanding, says Boustead, especially for those involved in some games that can have millions of active players.
+Boustead says the main problem with current 'voice over internet' technology is that it is one-dimensional; there is no relationship between how someone's voice sounds and the position they are at in the virtual landscape.
+But in the new system, a person's voice 'moves' around with their online character.
+This makes it possible to have multiple online conversations going on at the same time. People can get closer to those they want to hear and move away from those they are less interested in hearing.
+"The idea is that you can walk into a virtual crowd," says Boustead.
+"You can talk to people just like in normal life, in real life. And it's quite a comfortable way of communicating with people. People are actually very used to it."
+Immersed in a virtual world
+For games and other virtual reality devices, this means people can become even more immersed in their virtual world.
+"With our system you see through the eyes of your character, you see these other characters which other people are controlling, and you hear them from where they look like they are in the game," says Boustead.
+"So if someone is way up in front you'll hear them just slightly off in the distance in the front," he says. "If they're right up close they'll be loud."
+He says being able to talk to others in a crowd is important for players in computer games where co-operation with a small group within a crowd is crucial to winning. 
+It also means you can focus on the task at hand, rather than typing to communicate in text, says Boustead.
+He says the new technology could also be useful for virtual classrooms where students want to listen to the teacher and then form small discussion groups.
+The technology could be useful for corporate meetings, interactive online conferences or other events, says Boustead.
+"You could have a cocktail party online," says Boustead. "It could be kind of cool."
+Delivering the service
+The main restrictions on voice over internet has been a lack of bandwidth because having numerous voices and information that identifies their location in space involves a lot of data.
+But Boustead says his team has been developing technology that will allow such information to be sent via normal consumer broadband internet.
+The system involves an audio server, which creates 'audio scenes', connected to devices on PCs.
+Telstra has been running a trial using the voice technology with several online computer games over the last few months with a small group of broadband users.
+The research is funded by the Smart Internet Technology CRC.
+
+Laonastes is the only living representative of the otherwise extinct Distomydae, a family of rodents that lived in south Asia and Japan
+A squirrel-like rodent found last year in Laos has been identified as belonging to a family of rodents thought to have died out 11 million years ago, scientists says.
+A team of US, French and Chinese researchers compared the live animal's skeleton to the fossils of a family of rodents that lived in Asia in the early Oligocene to late Miocene eras.
+They confirm, in the latest issue of the journal Science, that it belonged to the same mammalian family.
+When the animal was discovered, it made the headlines as biologists thought it belonged to a new family of animals, rather than just a new species of an existing family. 
+They named it Laonastes aenigmamus, or Laotian rock rat. 
+In fact it belongs to the family Diatomyidae and resembles a small squirrel but is not a rat, says palaeontologist Dr Mary Dawson, of the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania. 
+Diatomyidae lived during the middle Tertiary period, 34 to 11 million years ago, in southern Asia, central China and Japan.
+They were medium sized rodents and had characteristic molar teeth and jaw structure.
+The researchers say the rodent is an example of the 'Lazarus effect', when an organism suddenly reappears after a long gap in the fossil record.
+Finding an animal thought to be extinct is even more exciting than discovering a new species, says Dr George Schaller, the Wildlife Conservation Society biologist who stumbled across the new animal last year.
+The rodent is a nocturnal mammal that inhabits a remote Laotian jungle, and is known to local ethnic groups who call it kha-nyou. 
+Scientist have been unable so far to see a live specimen. The only one found had been killed by hunters and was put on sale at a local market where it was spotted by conservation society researchers.
+
+The rainbow serpent, a key Aboriginal Dreamtime creation symbol, is closely connected with Indigenous knowledge of groundwater systems
+Indigenous Australians dug underground water reservoirs that helped them live on one of the world's driest continents for tens of thousands of years, new research shows.
+The study, which is the first of its kind, indicates Aboriginal people had extensive knowledge of the groundwater system, says hydrogeologist Brad Moggridge, knowledge that is still held today.
+Some 70% of the continent is covered by desert or semi-arid land, which meant its original inhabitants needed to know how to find and manage this resource if they were to survive.
+"Aboriginal people survived on one of the driest continents for thousands and thousands of years," says Brad Moggridge, who is from Kamilaroi country in northern New South Wales.
+"Without water you die. They managed that water sustainably."
+Moggridge, currently a principal policy officer in the New South Wales Department of Environment and Conservation, did his research as part of a Masters degree at the University of Technology, Sydney.
+He based his work on oral histories, Dreamtime stories, rock art, artefacts and ceremonial body painting as well as written accounts by white missionaries, surveyors, settlers, anthropologists and explorers.
+Managing scant resources
+Moggridge says Indigenous Australians channelled and filtered their water, covering it to avoid contamination and evaporation. They also created wells and tunnel reservoirs.
+"Groundwater was accessed through natural springs or people used to dig tunnels to access it," he says.
+"Sometimes they'd dig till they found the water and then they'd build a system so they could access the water. Sometimes they've go fairly deep and people would slither down there and get their water."
+Aboriginal people also used terrain, birdlife, vegetation and animals as markers for water, Moggridge says.
+For example, they followed dingos to rock pools and waterholes while ants led them to subterranean reservoirs.
+"They used the landscape," he says. "For example, you're in a dry area and all of a sudden there's a large number of ghost gums, so you'd think there must be some groundwater."
+The Dreamtime
+Aboriginal people's understanding of their groundwater system permeates Dreamtime stories, Moggridge says.
+For example, the rainbow serpent is a key symbol of creation but its journey from underground to the surface also represents groundwater rising to the top via springs.
+Moggridge says European settlers owed their subsequent knowledge of groundwater to local tribes and trackers, and even much of Australia's modern road system is based on water sources identified by the original inhabitants.
+"A lot of the old roads in New South Wales are based on Aboriginal walking tracks ... and their water supply would have been along the way," he says.
+The Desert Knowledge CRC is also trying to link traditional knowledge with science in terms of water management in central Australia, home to numerous remote Indigenous communities.
+Current projects include looking at the cultural values of water, a spokesperson says.
+
+Letting worrying or persistent thoughts into your head before you go to sleep is the best way to avoid having dreams or nightmares about them
+Advice to forget about your worries before bedtime can backfire, according to new research.
+An Australian study has found that trying to banish unwanted thoughts, like money problems or relationship dramas, actually leads to having more dreams or nightmares.
+The study, published online in the journal Behaviour Research and Therapy, found the phenomenon more pronounced in people who tend to shut out their worries.
+Lead researcher Professor Richard Bryant, a psychologist from the University of New South Wales and colleagues evaluated the effect of thought suppression on dreams in 100 psychology students at the university. 
+The students were asked to nominate an unwanted thought that regularly intrudes their minds.
+The group that actively suppressed the nominated thought just before dropping off to sleep reported more dreams featuring the unwanted thought compared to the group that did not suppress it.
+Bryant says that when the mind tries to block out unwanted thoughts it searches for alternative thoughts that prevent the unwanted thought from coming to mind (distraction), and monitors for any sign of the unwanted thought (detection). 
+"People who are highly anxious, or have a lot of things on their mind, the distraction process suffers, allowing the detection process to predominate, and they are going to think more about the unwanted thoughts," he says.
+Theories suggest the tendency to suppress certain thoughts leads to a higher susceptibility to psychiatric difficulties that involve intrusive thoughts, including depression, anxiety and obsessional thinking. 
+In the extreme, Bryant says, trying to suppress unwanted thoughts can lead to insomnia, psychological distress and fear of going to sleep.  
+Let the thoughts flow 
+"Most modern therapies for anxiety disorders, where thought intrusions are a core feature, now concentrate on getting the person to focus on their intrusive thoughts rather than suppress them," says Bryant.
+Bryant points out that intrusive thoughts are not always negative. Teenagers not wishing to keep thinking about a girlfriend or boyfriend when they are meant to be concentrating on other things can find themselves dealing with the same paradox, Bryant says.
+"The research will help us to shed light on how to manage unwanted thoughts more effectively. If you want to stop a thought bothering you, the best thing you can do is let the subject pop into your mind rather than try to suppress it."
+
+Stem cells harvested from young women's menstrual blood have a longer lifespan than those from older women
+Japanese researchers have harvested stem cells from human menstrual blood, a medical conference has heard.
+The researchers say these stem cells could be coaxed into forming specialised heart cells, which might one-day be used to treat failing or damaged hearts.
+At the meeting of the American College of Cardiology, Dr Shunichiro Miyoshi reported that he and his colleagues at Keio University in Tokyo collected menstrual blood from six women and harvested stem cells that originated in the lining of the uterus.
+They were able to obtain about 30 times more stem cells from menstrual blood than from bone marrow, Miyoshi says. 
+The stem cells were then cultured in a way to induce them to become heart cells.
+After five days about half of the cells contracted "spontaneously, rhythmical and synchronously, suggesting the presence of electrical communication" between the cells, Miyoshi says.
+That is to say, they behaved like heart cells. 
+The researcher explains that already stem cells derived from bone marrow have improved heart function, mainly by producing new blood vessels rather than new heart-muscle tissue.
+He emphasises that it is important that these cells be obtained from younger patients, because they would have a longer lifespan than cells harvested from older donors.
+
+This exoplanet is 13 times the mass of Earth and is shown here with a hypothetical moon
+A cold, heavy 'super-Earth' has been found orbiting a distant star, using a method that holds promise for detecting faraway planets that closely resemble our own, astronomers say. 
+The planet weighs 13 times as much as Earth and is orbiting a star about 9000 light-years away.
+But instead of circling close to its star, as Earth does, this super-Earth is about as distant from its star as Jupiter and Saturn are from the Sun. 
+An international team of scientists says the new planet probably has a temperature of minus 201&deg;C, making it one of the coldest planets detected outside our solar system. 
+The discovery is billed as a super-Earth because it is thought to be a rocky, terrestrial planet like Earth, even though it is much more massive.
+The planet was detected by astronomers using a project called OGLE, short for Optical Gravitational Lensing Experiment, which looks for changes in light coming from distant stars.
+If another star passes between the faraway star and a telescope on Earth, the gravity of the intervening star acts like a lens and magnifies the incoming light. 
+When a planet is orbiting the closer star, the planet's gravity can add its own distinctive signature to the light. 
+This phenomenon is known as gravitational microlensing, and it has the potential to detect less massive planets than other methods of searching for planets around other stars. 
+Lots of super-Earths
+The OGLE project detected the microlensing event in April; a total of 36 astronomers working with OGLE found the signs of a planet, 9000 light-years away in the direction of the Milky Way's central galactic bulge. 
+A light-year is about 10 trillion kilometres, the distance light travels in a year. 
+Professor Andrew Gould of Ohio State University who heads the planet-hunting group MicroFUN, short for Microlensing Follow-Up Network, says this discovery has two implications. 
+"First, this icy super-Earth dominates the region around its star that in our solar system is populated by the gas-giant planets, Jupiter and Saturn," Gould says.
+"We've never seen a system like this before, because we've never had the means to find them. 
+"And second these icy super-Earths are pretty common. Roughly 35% of all stars have them."
+The researchers report their find on arXiv, a website run by Cornell University.
+In the past decade, scientists have detected some 170 so-called extrasolar planets, using a variety of techniques. The vast majority are gas giant planets like Jupiter that are hostile to life as it is known on Earth. 
+In January, a planet about five-and-a-half times Earth's mass circling a star near the center of the Milky Way was detected using gravitational microlensing.
+
+A circular shape protects certain proteins from being chewed up by enzymes. So could these super-tough proteins be used to deliver drugs?
+Humans appear to have lost what may have been a natural resistance to HIV some 7 million years when our bodies stopped producing particular kinds of protein, an Australian scientist says.
+These circular proteins, called cyclotides, were discovered by Professor David Craik from the University of Queensland and colleagues, about 10 years ago.
+Craik reports new insights into these molecules in the current issue of the journal Science.
+The first cyclotide discovered in mammals, RTD1, was found in rhesus monkeys and when chemically synthesised acts against HIV.
+Craik says humans have the genetic material to produce RTD1 but we don't make it because during evolution we apparently developed a mutation, which put a "stop code" on its production.
+"It seems that somewhere between 7 and 10 million years ago some primates retained this mutation," Craik says.
+"It's an ironic twist of fate because if it wasn't for that mutation you and I would have a gene that would produce a potent anti-HIV agent."
+The discovery could also explain why some people have apparent immunity to HIV, Craik says.
+"There may be some populations that don't have the stop code," he says.
+Help during childbirth
+Craick reported his discovery of the first cyclotide in 1995 after analysing a small circular protein from a medicinal tea given to Congo tribeswoman during childbirth.
+"We discovered that this molecule had a circular backbone and a knotted arrangement ... that made it virtually indestructible," he says. It was completely resistant to enzymes and boiling.
+"We thought it was unusual that a protein could be so stable and that's why we tried to find out the structure."
+Almost all of the 100 or so cyclotides discovered so far have come from plants, animals and bacteria.
+Cyclotides
+His investigations show that while normal proteins are a linear chain of amino acids, cyclotides have "stitched up ends" that protect them from degradation.
+"There are a lot of enzymes around whose job it is to degrade proteins," he says.
+"They target the ends of proteins, and chop away at the ends. 
+"Cyclotides are therefore resistant to degradation because they are joined from head to tail to form a circle."
+Cyclotides are also naturally occurring, compared to other small circular proteins, or cyclic peptides, which have either been physically manipulated in the lab or "arranged" by a chemical interaction in the body.
+Craik says some of these peptides have been identified as promising drug leads but they fall down as medicines because they basically get chewed up by enzymes once they're swallowed. 
+"As far as your body's concerned a protein drug is the same as a piece of steak, all it wants to do is chew it up," he says.
+But natural cyclotides can be toxic.
+Delivering drugs
+Craik says the solution is to chemically engineer cyclotides to remove their toxicity, then graft active peptides onto them, using the construct to deliver drugs.
+"We're engineering out the toxic effects and engineering in the biological activity," he says.
+Craik is working on this principle using plant cyclotides and is currently commercialising a drug for multiple sclerosis.
+
+Tiny speck of comet dust, less than 500 micrometres long, and its track embedded in low-density glass
+Scientists studying comet samples returned by the Stardust spacecraft have uncovered a cosmic conundrum. How did minerals that form in extremely hot temperatures end up inside an icy comet? 
+"When they formed, they were either red-hot or white-hot and we found them in the Siberia of the solar system," says Stardust lead scientist Professor Donald Brownlee, with the University of Washington. 
+The Stardust spacecraft was launched in February 1999 and flew by Comet Wild 2 (pronounced 'vilt 2') five years later.
+The comet formed in the frigid Kuiper Belt region located beyond Neptune's orbit and was a relatively new traveller to the inner solar system when it encountered the NASA probe. 
+Samples from the comet were collected by the spacecraft in trays of exposed gel and returned to Earth in January. 
+The discovery of exotic, high-temperature minerals rich in calcium, aluminum and titanium complicate generally accepted theories about how comets form. 
+Far from simple icy bodies with clouds of gas and dust, comets, or at least Comet Wild 2, now appear to be a blend of materials formed at all temperature ranges. 
+Forging metals
+Brownlee and other Stardust researchers expect to learn whether the high-temperature metals were forged near the center of the nebular cloud that eventually became our solar system or whether they come from another star. 
+"If it was formed in our solar system, then it had to be transported from the hottest regions to the coolest," says Brownlee. 
+The samples also show a rich supply of olivine, an iron-magnesium blend of minerals, which on Earth can be found in peridot gemstones and in the green sand on some Hawaiian beaches. 
+Though it is one of the most common minerals in the universe, scientists did not expect to find it in a comet. 
+Olivine forms in temperatures of about 1100&deg;C, which means the mineral would have had to form closer to the Sun than Mercury and then somehow be flung out more than 45 times the distance of the Sun to Earth. 
+Researchers plan extensive studies to determine the chemical histories of the sample particles, which will eventually reveal whether the grains came from our solar system or another star. 
+"We will know soon," Brownlee said at the annual Lunar and Planetary Institute's science conference, which opened this week.
+Between 150 and 200 samples from the comet are currently circulating among scientists and research labs across the world. 
+Next month, work begins on another set of samples collected during the mission: interstellar dust grains. 
+Unlike the comet samples, the bits of interstellar dust picked up during Stardust's travels are tiny. 
+Scientists plan an internet-based detection program of volunteers who will use their home computers to scrutinise images and try to identify any particles. The project, called Stardust@Home, begins in April.
+
+This false-colour image of Earth shows heat escaping to space. Greenhouse gases trap such heat to warm the planet
+Greenhouse gases in 2004 reached their highest ever levels in the atmosphere, says the UN's meteorological agency.
+A bulletin from the World Meteorological Organization (WMO) says the gases carbon dioxide (CO2), methane and nitrous oxide "all reached new highs in 2004". 
+Officials also indicate that a near record year-on-year rise in CO2 levels for 2005 recorded by US monitors, well above the average for the past 10 years, would not come as a major surprise. 
+"Global observations coordinated by WMO show that levels of CO2, the most abundant greenhouse gas in the atmosphere, continue to increase steadily and show no signs of levelling off," says WMO secretary-general Michel Jarraud.
+In its first Greenhouse Gas Bulletin, to be an annual publication, the WMO says that in 2004 atmospheric CO2 levels stood at 377.1 parts per million, 35% higher than in the pre-industrial age, before about 1750.
+Methane has risen 155% in the modern age, the WMO says, but its growth is slowing.
+And nitrous oxide is rising consistently, with levels increasing 18% in modern times.
+The WMO says these three gases alone contribute to about 88% of warming over the same period.
+The average annual increase in absolute amounts of CO2 in the atmosphere over the past decade has been 1.9 parts per million, slightly higher than the 1.8 parts per million of 2004, says WMO environment division chief Dr Leonard Barrie.
+Barrie says reports by National Oceanic and Atmospheric Administration that CO2 had grown last year by 2.6 parts per million had to be viewed in perspective.
+"It is important to take the long view. There can be fluctuations," he says. "The 2.6 parts per million figure is within past experience. If it were to persist over several years, then we would have to start talking about what it means."
+
+Recurrent miscarriages could be prevented if women prone to thrombophilia are given the correct treatment, new research finds
+Women who have had recurrent miscarriages should be checked for a tendency to develop blood clots as treating the condition halves their risk of further pregnancy loss, a new study has found.
+Australian researchers followed 220 couples who had had at least three miscarriages.
+They found that screening the women for thrombophilia, a tendency to develop blood clots, and giving them prophylactic anti-thrombotic therapy halved their future chances of losing a pregnancy.
+Professor of obstetrics and gynaecology at the University of Adelaide, Gus Dekker, says the women were screened for thrombophilia, insulin resistance and elevated homocysteine levels. 
+"We found that if you do nothing, these women can expect a 30% to 35% chance of a further miscarriage," he says. 
+"But if you treat them, the pregnancy loss rate is halved to 15%. There is light on the horizon for women who have recurrent miscarriages as proper analysis and treatment can increase the chance of having a healthy baby from 70% to 85%."
+Anti-thrombotic therapy includes aspirin plus low molecular weight heparin. Treatment for elevated levels of homocysteine, which is another risk factor for clotting, is vitamins including folate and vitamin B12.
+Professor Dekker presented findings at the recent Human Reproductive Health Through the Ages conference in Adelaide.
+He says the data, literature and the researchers' own experience indicate that screening identified major risk factors in 50-60% of recurrent miscarriage cases.
+"We can modify most of these risk factors such as insulin resistance and thrombophilias," he says.
+He advises these women should be referred to an obstetrician with a special interest in the area.
+Dekker says women who had had three miscarriages or women in their mid-30s who had had two, and did not have a condition known as a blighted ovum, could be referred.
+Women with a personal or family history of thrombophilia could also be referred, as could women with a history of pre-eclampsia or unexplained preterm birth.
+"Most thrombophilias affect the early development of the placental circulation so treatment to prevent thrombosis and possibly provide an anti-inflammatory effect, can stop the process," he says.
+
+The same mathematical used to schedule trains are being used to prioritise the allocation of scarce conservation dollars
+Scientists are using mathematical formulae normally used by economists and engineers to work out which of the world's biodiversity hotspots to save first.
+Ecologist and mathematician Professor Hugh Possingham and team at the University of Queensland report their research in today's issue of the journal Nature.
+Since the 1980s, global conservation agencies have identified particular areas around the world that are rich in species but under threat from habitat destruction.
+But there are many such 'biodiversity hotspots' that need attention, and a limited budget to save them.
+Until now, says Possingham, there hasn't been a rational way of prioritising where to act first.
+"Do you act in them all simultaneously? Do you try and pick out three of them? And how long do you spend acting in one before you move to another?"
+Possingham's team has applied mathematical tools regularly used by economists and engineers to find the optimum way to answer these questions.
+"[The tools] run our entire economy, they schedule all the airlines, they schedule all the trains," says Possingham.
+"Any transportation organisation is using optimisation methods to work out which trucks should go where at what times."
+He says in this case the tools are applied to saving as many species as possible.
+"In a sense it's not that much more than third year or fourth year applied maths or economics at university," says Possingham.
+"But the kind of people working in these [conservation] fields often don't have these skills so they often thought about formulating the problem properly."
+Prioritising hotspots
+Possingham's team has developed a method of prioritising hotspots that take into consideration a range of features apart from how many species an area has.
+High priority is given to areas where habitat is fast disappearing, little of the area has already disappeared, and where the cost of conserving habitat is low.
+Another factor that influences the priority given to an area is how likely it is to conserved in the future.
+"If you are going to invest in a place where you're not sure that you'll get the investment, you're not sure the national park will stay a national park, you'd want to get a lot more benefit out of that investment," says Possingham.
+"You're willing to pay higher prices for places that are secure."
+He says this is exactly the same as trade-offs made in the share market, where you expect a higher outcome for high-risk investments and a lower outcome for low-risk ones.
+The team is currently working with Conservation International and The Nature Conservancy to help establish conservation priorities across the globe.
+So far Possingham and team have tested their method on five areas in South East Asia and found that Sulawesi would be a higher priority than Sumatra, Borneo, Java and Malaysia.
+
+Supermarket databases could be vulnerable to virus attacks, causing chaos at the checkout
+Cheap radio chips that are replacing the ubiquitous barcode are a threat to privacy and susceptible to computer viruses, scientists say.
+And a deliberate virus attack could potentially cause chaos at airports and supermarkets.
+Researchers at Amsterdam's Free University created a radio frequency identity (RFID) chip infected with a virus to prove that RFID systems are vulnerable despite their extremely low memory capacity. 
+The problem is that an infected RFID tag, which is read wirelessly when it passes through a scanning gate, can upset the database that processes the information on the chip, say the study authors.
+"Everyone working on RFID technology has tacitly assumed that the mere act of scanning an RFID tag cannot modify back-end software and certainly not in a malicious way. Unfortunately, they are wrong," they say.
+"An RFID tag can be infected with a virus and this virus can infect the back-end database used by the RFID software. From there it can be easily spread to other RFID tags."
+As a result, they say, it is possible that criminals or militants could use an infected RFID tag to upset airline baggage handling systems with potentially devastating consequences.
+The same technology could also be used to wreak havoc with the databases used by supermarkets. 
+"This is intended as a wake-up call. We ask the RFID industry to design systems that are secure," says author Professor Andrew Tanenbaum.
+With RFID, anything from shampoo bottles to marathon runners can be tracked using radio tags. 
+Civil liberty groups say RFID could lead to an unacceptable invasion of privacy and argue that airline ticket information could be used by law enforcement agencies and divorce lawyers. 
+Industries in which tracking goods is crucial such as pharmaceuticals, governments, logistics, airlines and manufacturing already use RFID technology.
+
+The concave-eared torrent frog needs to 'shout' to be heard over the sound of rushing water. It uses a form of communication before now only seen in mammals
+A rare frog uses ultrasound to communicate, a clever tool that helps it overcome the noise of the waterfalls it lives in, researchers say.
+The concave-eared torrent frog (Amolops tormotus) is the first non-mammalian species known to use the ultra-high frequencies that humans cannot hear.
+It joins bats, dolphins and whales, and a small number of rodents, in the elite club of creatures that can communicate this way. 
+A US and Chinese team reports its find today in the journal Nature. 
+Professor Albert Feng of the University of Illinois and team found that male frogs of the species make high-pitched melodic bird-like calls.
+The calls sometimes exceeded their recorder's maximum range of 128 kilohertz, more than six times the limit of human hearing. 
+The frogs inhabit Huangshan Hot Springs, a popular mountainous area west of Shanghai, where there are loud waterfalls and streams. 
+The high frequencies provide a channel of communication that cannot be disrupted by the lower-frequency rumble of the water, says Feng. 
+"Nature has a way of evolving mechanisms to facilitate communication in very adverse situations," he says. 
+"One of the ways is to shift the frequencies beyond the spectrum of the background noise. Mammals such as bats, whales and dolphins do this, and use ultrasound for their sonar system and communication. Frogs were never taken into consideration for being able to do this." 
+The discovery also answers a puzzle as to why the frogs do not have external eardrums. 
+"Thin eardrums are needed for detection of ultrasound," says Feng. "Recessed ears shorten the path between the eardrums and the ear, enabling the transmission of ultrasound to the ear." 
+Ultrasounds are high-pitched sounds with a frequency of more than 20 kilohertz, much higher than the frequency most birds, reptiles and amphibians can hear.
+
+Long, single strands of DNA, plus strengthening shorter strands, were used to make this image
+A nanotechnologist has created the world's smallest and most plentiful smiley, a tiny face measuring a few billionths of a metre across assembled from strands of DNA.
+Dr Paul Rothemund at the California Institute of Technology can make 50 billion smileys, each a thousand times smaller than the diameter of a human hair, with his technique.
+DNA has long been known for its versatility as a microscopic building block. 
+The molecule can be 'cut' using enzymes and reassembled using matching rungs in its double-helix structure.
+This theoretically opens the way to making DNA quantum computers and nano-level devices including injectable robots that can monitor the body's tissues for good health. 
+But, until now, nano-assembly has been a complex atom-by-atom procedure that is also costly, because it is carried out in a vacuum or at extremely coldly temperatures. 
+Rothemund, writing in today's issue of the journal Nature, describes a far simpler and much cheaper process in which long, single strands of DNA can be folded back and forth to form a basic scaffold. 
+The basic structure is then supplemented by around 200 shorter strands, which both strengthen it and act rather like pixels in a computer or TV image, thus providing a shape that can bear a complex pattern. 
+In a potent demonstration of his so-called DNA origami technique, Rothemund has created half a dozen shapes, including a five-pointed star, a snowflake, a picture of the double helix and a map of the Americas in which one nanometre represents 120 kilometres. 
+Rothemund has been working on flat, two-dimensional shapes but says that 3D structures in DNA should be quite feasible with this technique.
+One application would be a nano-scale 'cage' in which pharmaceutical researchers, working on novel drugs, could sequester enzymes until they were ready for use in turning other proteins on and off.
+
+Whether your brain triggers you to act violently or not is determined by a complex mix of genes and environment
+People who are genetically predisposed to violence have a different brain structure to others, a new study suggests.
+Dr Daniel Weinberger, of the US National Institute of Mental Health and team report their findings in today's issue of the Proceedings of the National Academy of Science.
+"[Our] data identify neural mechanisms associated with one specific gene epidemiologically associated with risk for violent and impulsive behaviour," they say.
+The gene, which is carried on the X chromosome, produces an enzyme that mops up stress hormones in the brain.
+Some researchers suggest that a certain form of this monoamine oxidase A (MAOA) gene is linked to violent behaviour.
+According to Australian neurogeneticist Professor Peter Schofield the most profound demonstration of the link was a study more than 10 years ago of a rare family in the Netherlands that had a catastrophic mutation in that gene.
+"All the males in that family with that mutation were arsonists and rapists," says Schofield, who heads the Prince of Wales Medical Research Institute in Sydney.
+In addition, he says, animal studies have shown that mice without an MAOA gene have aggressive tendencies.
+These drastic exceptions aside, the MAOA gene occurs naturally in all of us in one of two forms, one that expresses the enzyme at very low levels, and one that expresses it at high levels.
+Some researchers think that there might be a correlation between the low-expressing form and violent behaviour.
+But a study done a few years ago, of 1000 men born in the New Zealand city of Dunedin, found no direct link between the gene form and violent behaviour.
+What they did find was an indirect link: those men who had the low-expressing version of the MAOA gene and had been abused as children were far more prone to violent behaviour.
+Now, Weinberger and team have tried to find out more about how this complex interaction of genes and environment works.
+The study
+Weinberger and team studied the genes and brains of 142 healthy men and women, who had no history of violence.
+The researchers showed the study participants pictures of angry and fearful faces and monitored the structure and function of their brains using magnetic resonance imaging.
+They found those with the low-expressing version of MAOA were more impulsive.
+Parts of their brain associated with emotion differed in size and activity to those with the high-expressing version.
+The study also found that activity of those parts of the brain in males with low-expression MAOA differed more greatly than their female counterparts.
+Weinberger and team say their work sheds light on the neural mechanisms involved in genetic predisposition to violence and it could help in finding ways to combat violence using biological approaches.
+But they emphasise the genetic contribution to violence is small.
+Nature and nature
+Schofield welcomes the new research saying it builds on the previous Dunedin study by exploring how genes and environment can interact.
+"It's neither nurture nor nature, it is a complex mixture of both," he says.
+Schofield says the main weakness of the study is that it studied normal people and extrapolated what this might mean for violent people.
+He says the obvious next step would be to see if the results held true for a group of people who had a history of violent crime.
+But he says, if the emotional seat of the brain is involved, it suggests that cognitive behavioural therapy may be a useful tool to counter violent behaviour.
+Neuroscientist Professor Lesley Rogers of the University of New England in Armidale also welcomes the study.
+"This expression of MAOA form is really important in terms of how a brain will deal with a social situation, whether [a person will] go over the top or not," says Rogers, who has written extensively on the relationship between genes and environment.
+
+The deep sea is rich in unusual creatures that biotech companies are keen to exploit. This hydrothermal vent, for example, is home to riftia tubeworms mussels and scavenging crabs
+Biotechnology companies are profiting from living resources found in the deep ocean without laws to ensure their actions are sustainable and fair, says an Australian environmental lawyer.
+Dr David Leary of Macquarie University in Sydney says his research has revealed there are six companies selling products derived from the deep ocean and another eight developing them.
+"They are the main players in the biotech industry; they're North American and European companies," he says.
+Leary says while international laws cover mining in the deep sea, no-one is mining there yet.
+"[But] we have bioprospecting and exploitation of the genetic resources of the deep sea, beyond national jurisidiction," says Leary, who describes the deep sea as one of the world's last remaining commons.
+"People are making a profit now," he says.
+Leary says national scientific research organisations in Japan, France, US, Russia, Australia, Canada and New Zealand are also involved in bioprospecting in the deep sea.
+He says biotech companies rely on these public organisations for access to deep-sea resources because the companies don't own the specialised equipment needed to explore the deep sea.
+"What is difficult, because of commercial confidentiality, is getting a handle on how close industry is to government science," says Leary.
+Cosmetics, drugs, industrial enzymes
+He says there are 37 patents, filed in Europe and the US, on derivatives of deep-sea organisms.
+There are cosmetics on sale derived from microbes that survive in extreme environments found deep below the surface of the ocean, says Leary, and enzymes from the same source are used in industrial processes and research.
+A French government agency is currently testing a bone-healing drug also made from these extremophiles, he says.
+And there is research into developing artificial blood from the haemoglobin of tubeworms found around deep-sea hydrothermal vents.
+There is also research on chemicals from corals on deep-sea mounts, says Leary.
+
+Part of the Maldives island chain from space: Nearly 100 people were killed here following the 2004 tsunami, and over 20,000 were displaced
+Some of the low-lying islands of the Maldives grew taller as a result of the deadly 2004 Indian Ocean tsunami, a new study has found.
+Dr Paul Kench, of the University of Auckland in New Zealand, and team report their findings in the March issue of the journal Geology. 
+Despite the disastrous effects of the tsunami on humans and man-made structures in the Maldives, less than 5% of the land area was significantly changed by the tsunami, say the researchers. 
+A before-and-after study of 13 small islands suggests that the low-lying coral atolls are tougher than they look. 
+"We looked for any evidence of change," says Kench. 
+He and his team had already surveyed 13 small islands in the Maldives, before the tsunami in 2002 and 2003, so they were in a perfect position to assess the effects of the tsunami. 
+The first thing Kench and his team discovered was that the tsunami was not nearly as high at the Maldives as along other coasts. That's because there is no continental shelf along which the waves could build up and break. 
+Instead, says Kench, the highest in the series of waves from the Great Sumatra-Andaman Earthquake were only about 3 metres, which washed over the 1.5 to 2 metre-high islands and then kept racing toward Africa. 
+"There weren't these thundering walls of water crashing across the islands," says Kench. "Nevertheless, they all went underwater." 
+The islands were also spared any backwash, which doubled the scouring effect elsewhere, Kench says. 
+On the contrary, the tsunami scoured only the eastern sides of the islands, where it struck and carried the coral beach sand over the islands. As much as 30 centimetres of sand was deposited on top of one island, with the others gaining 5 to 10 centimetres. 
+"It just added freeboard," says Kench. 
+The bottom line, he says, is that geologically speaking, the tsunami was anything but a destructive event for the island landmass of the Maldives. 
+"I think it's a quite useful paper," says marine geologist Dr Chris Perry at Manchester Metropolitan University in the UK. "The [island] response is fairly minimal." 
+But it's not clear whether it offers any clues to how the Maldives or other atolls will withstand rapid rises in sea level due to the melting of glaciers by global warming. 
+"We don't know the rates of [reef] growth," says Perry. 
+And there's also the fact that many atolls are now suffering from coral bleaching, which stops growth altogether.
+
+Just like her screen depiction by movie star Elizabeth Taylor, Cleopatra knew all about power hair
+Egyptian queen Cleopatra used her hairstyles to enhance her power and fame, says a professor of art history and classics.
+Statues, coins and other existing depictions of the queen suggest Cleopatra (69-30 BC) wore at least three hairstyles, Professor Diana Kleiner of Yale University says in a new book.
+The first, a "travelling" do that mimicked the hair of a Macedonian Greek queen, involved sectioning the hair into curls, which were then often pulled away from the face and gathered into a bun at the back.
+The next was a coiffure resembling a melon, and the third was the regal Cleopatra in her royal Egyptian headdress, complete with a rearing cobra made of precious metal.
+Cleopatra did not invent any of these styles, but she used them to her advantage, Kleiner indicates in her book Cleopatra and Rome.
+Ptolemaic trendsetters
+From the time of Egyptian King Ptolemy I, the Ptolemaic queens wore the 'melon hairstyle' with its segmented sections resembling a melon or gourd," Kleiner says.
+"When Cleopatra followed suit, she was more traditionalist than trendsetter.
+"These same Ptolemaic queens were also depicted in art with the usual Egyptian wigged headdress that had its origins in Pharaonic times.
+"Cleopatra did as well, so again she followed tradition and did not innovate when it came to hair."
+"But," Kleiner says, "Cleopatra appears to have worn different coiffures in different circumstances, playing to her audience, so to speak, in life and in art."
+Kleiner says when the queen was in her homeland, her likely objective was to look like a traditional Egyptian ruler, although she was in fact Greek, and to legitimise the Ptolemaic dynasty by linking it to the time of the Pharaohs.
+A group of Egyptian statues recently has been linked to Cleopatra, although the identification can't be proved since there are no accompanying inscriptions.
+"These show her with the customary Egyptian wig and the triple uraeus (rearing cobra)," she says.
+"This Egyptian coiffure is the one we most often associate with Cleopatra today. Think Elizabeth Taylor!" 
+Divine ornaments
+The uraeus was associated with a cobra goddess Wadjyt, the sun god Ra and the goddess Hathor, so wearing it signified that the individual had taken on the attributes of a divinity.
+Cleopatra also probably often wore the melon hairstyle in Egypt, where she had many slaves to attend to her appearance, including some that were responsible for maintaining the royal wigs.
+The Egyptian queen extensively travelled, and did so in style. Not unlike film depictions, Cleopatra would arrive via elegant barge with her attendants catering to her every need.
+In Rome, Kleiner believes Cleopatra wore her "Hellenistic travelling coiffure" in places where it would be seen and "gossiped about at cocktail parties."
+At about the same time, Kleiner notes the melon hairstyle turns up in Roman portraiture, which suggests Roman women admired Cleopatra and attempted to copy her.
+Nodus operandi
+Roman leaders Octavian, Antony and Julius Caesar seduced the Egyptian queen.
+Kleiner suggests that Octavia, Antony's wife, invented a hairstyle called "the nodus" to compete with Cleopatra.
+ The nodus featured a roll over the forehead that Kleiner says may have mimicked Cleopatra's well-known rearing cobra.
+The nodus was the height of Roman fashion in the 30s BC, just before Cleopatra's death by suicide at the age of 39.
+Karl Galinsky, distinguished professor of classics at the University of Texas at Austin, says he agrees that Cleopatra wore different looks, including calculated hairstyles.
+He says they were designed to convey a message and Cleopatra may have had different hair days in different countries.
+
+Drug research company Parexel carried out a drug trial that went horribly wrong. Could it happen in Australia
+As doctors scramble to understand what caused the catastrophic reaction to a drug given in a UK trial, researchers say the possibility of something similar happening in Australia can't be ruled out.
+British experts are baffled about why six healthy volunteers suffered a massive reaction shortly after being given the antibody drug TGN1412 last week.
+Two remain critically ill and four are seriously ill. Two others who received a placebo escaped harm.
+It's believed differences between a cell-signalling protein in humans and animals may explain the unexpectedly severe reaction in the previously healthy young men, who were paid for their participation.
+They were the first humans to receive the drug, designed to treat leukaemia and chronic inflammation disorders. 
+Australian clinical trials experts say we should learn a lesson from the UK experience and consider more sophisticated ways of trialling potentially dangerous new drugs.
+Dr Chris Karapetis, a principal investigator in several clinical trials in oncology at Flinders Medical Centre in Adelaide, says Australian trials are subject to rigorous ethical and scientific scrutiny but risks remain.
+"Obviously you cannot rule out the possibility of there being an adverse reaction in a trial of this nature," he says.
+"One of the things that is crucial ... is that all potential risks are explained to patients, and when it's a new drug, the risk that there could be a side effect that develops that's unknown."
+What went wrong?
+Doctors say they have never before seen a reaction such as occurred during the trial of TGN1412, made by privately owned German company TeGenero AG.
+US drug research company Parexel was running the trial on behalf of TeGenero.
+Dr Thomas Hanke, chief scientific officer at TeGenero, says previous tests on animals hadn't produced drug related adverse events or drug-related deaths.
+TGN1412 belongs to a class of drugs known as monoclonal antibodies, which specifically bind to target molecules. TGN1412 targets an immune system protein called CD28.
+CD28 is a protein on the surface of some white blood cells that plays a part in activating them for an immune response.
+Hanke says TGN1412 was designed to activate its target protein - rather than blocking it as many antibody drugs do.
+Dr David Glover, a UK drug industry consultant with extensive experience of antibody treatments, says the protein the drug targets may not be the same in all species. 
+"I suspect the antibody was designed to work against human CD28 and because it was designed to work best in humans its performance in different animals may fall short of what you might have expected in humans," he says. 
+"That is why the animal testing may have falsely provided reassuring results. It could be one of the explanations."
+What can Australia do?
+Australian clinical pharmacologist Professor Paul Rolan of the University of Adelaide has introduced 70 new molecules into humans during 20 years of clinical trials.
+He says TGN1412 is different to many other drugs because it has a very specific target in the body.
+"Such 'magic bullet' drugs can be very specific to humans and may not cause adverse reactions in animals used in preclinical trials," he says.
+Rolan says the way we do trials may need to become more sophisticated as we search for more specific and powerful drugs.
+Rather than testing these sorts of drugs in animals we may have to use animals that have been genetically modified to make them more like humans.
+He believes Australia has the expertise to do these sort of trials.
+The Garvan Institute of Medical Research in Sydney says it is already using these methods.
+In a statement, the Garvan says Australian clinical trials have "a fantastic record".
+"It is absolutely vital that both volunteers and patients continue to agree to participate in clinical trials for new medicines," it says.
+What's the future for antibody treatments?
+Glover says no one should lose sight of the benefits of antibody drugs.
+He says the focus shouldn't be on antibody treatments in general, or stopping clinical trials. 
+The breast cancer drug Herceptin, made by the Swiss pharmaceutical Roche, is an antibody treatment.
+It attaches itself to the HER2 receptor on the cancer cells and blocks them from receiving growth signal. 
+Eighteen antibody products have been approved for sale and their combined worldwide sales reached $US14 billion (A$19.3 billion) last year.
+But Glover says trials of drugs targeting the protein CD28 should be reviewed.
+"Should we stop doing trials that are directed against the target CD28? I think the answer is yes, until more is known about what it going on," he says. 
+The UK's Medicines and Healthcare Products Regulatory Agency is conducting an enquiry into what went wrong and results are expected in the coming weeks.
+
+Will bird flu vaccines be out of date by the time they are ready for use?
+The H5N1 bird flu in humans has evolved into two separate strains, a development that will complicate the search for a vaccine and the prevention of a pandemic, US researchers report. 
+The genetic diversification of the pool of H5N1 avian influenza viruses with the potential to cause a human influenza pandemic heightens the need for careful surveillance, researchers said at the International Conference on Emerging Infectious Diseases in Atlanta. 
+"Back in 2003 we only had one genetically distinct population of H5N1 with the potential to cause a human pandemic. Now we have two," says Dr Rebecca Garten of the US Centers for Disease Control (CDC), who helped to conduct the study. 
+One of the two strains, or clades, made people sick in Vietnam, Cambodia and Thailand in 2003 and 2004 and the second, a cousin of the first, caused the disease in people in Indonesia in 2005. 
+Two clades may share the same ancestor but are genetically distinct, as are different clades, or strains, of HIV, the team from the CDC found. 
+"This does complicate vaccine development. But we are moving very swiftly to develop vaccines against this new group of viruses," says Dr Nancy Cox, chief of the CDC's influenza branch.
+The H5N1 strain of bird flu has spread across Europe, Africa and parts of Asia and killed nearly 100 people worldwide and infected about 180 since it reemerged in 2003. 
+Although it is difficult to catch bird flu, people can become infected if they come into close contact with infected birds.
+Scientists fear the virus could mutate into a form that could pass easily between humans, triggering a pandemic in which millions could die.
+Transmission from human to human?
+All influenza viruses mutate easily, and H5N1 appears to be no exception. 
+But Cox says the evolution of a second clade does not move the virus closer to human-to-human transmission. 
+"Like the group one or clade one viruses, the group two or clade two viruses are not easily transmitted from person to person," she says.
+"It really doesn't take us closer to a pandemic. It simply makes preparing for the pandemic a bit more difficult." 
+The US Department of Health and Human Services has already recognised the two strains and approved the development of a second H5N1 vaccine based on the second clade. 
+Several companies are working on H5N1 vaccines experimentally, although current formulations are not expected to protect very well, if at all, against any pandemic strain. 
+A vaccine against a pandemic flu strain would have to be formulated using the actual virus passing from person to person.
+Partial protection
+Researchers say while vaccines were needed against different strains of the virus, a vaccination against one clade could provide partial protection against another. 
+"We would expect the priming [of a patient] with a clade one [vaccine] could potentially reduce the severity of disease," Cox says.
+For their study, Garten and colleagues analysed more than 300 H5N1 virus samples taken from both infected birds and people from 2003 through the northern hemisphere summer of 2005.
+Garten says the bird flu strains being detected in Europe are generally clade two strains.
+
+The northern Queensland town of Innisfail copped the full force of Cyclone Larry
+When tropical Cyclone Larry lashed the Queensland coast at the weekend it raised questions of whether it was a sign of a changing climate.
+Could it be the harbinger of a new drought-busting La Ni&ntilde;a weather cycle? Could it be a product of human-induced climate change?
+Or is it just too soon to tell?
+Larry slammed into Australia's northeast coast on Sunday morning, local time.
+Initial reports said it was the most powerful cyclone to hit the continent in decades, moving at unusual speed and packing winds of up to 290 kilometres an hour.
+Dr Geoff Love, director of meteorology at the Bureau of Meteorology (BOM) says Larry was on a par with Cyclone Tracey, which devastated Darwin in 1974.
+The BOM categorises cyclones from 1 to 5, with 5 being the most severe.
+Love says Larry was probably "high category 4, probably not quite 5" and neither unusual nor unexpected.
+"Larry was no different from any other tropical cyclone," he says.
+But Love says more cyclones hit tropical Queensland in La Ni&ntilde;a conditions, a possible sign that Australia is headed for a change after emerging from El Ni&ntilde;o three years ago.
+"With an El Ni&ntilde;o, cyclones tend to form out closer to the dateline and probably occur before they reach Australian longitude, in La Ni&ntilde;a they form closer to the Australian coast," he says 
+Pacific oscillations
+Records going back to the 1880's show a clear La Ni&ntilde;a-El Ni&ntilde;o cycle, Love says.
+The La Ni&ntilde;a  and El Ni&ntilde;o effects are two extremes of an atmospheric and oceanic oscillation in the Pacific Ocean.
+They have a direct and significant impact on climate in some parts of the world, including Australia.
+El Ni&ntilde;o occurs when the surface of the ocean warms and leads to drier conditions in Australia, which mean more droughts and fires.
+Cooling surface waters cause La Ni&ntilde;a , which causes wetter conditions and more flooding.
+The two phases switch every few years. But they don't always neatly alternate, making it difficult to make predictions.
+Love says there have been about 20 El Ni&ntilde;os and 20 La Ni&ntilde;a s in the past 120 years. 
+This amounts to about 20 six year cycles made up of roughly four neutral years and two years of El Ni&ntilde;o or La Ni&ntilde;a, or one year of each.
+Australia is currently in what Love calls a "neutral, weak, wishy-washy" period, although there are signs we're trending towards La Ni&ntilde;a.
+"I think we have been sort of just on the borderline," he says.
+"The Americans have a lower threshold, they're calling it a weak La Ni&ntilde;a. We're saying it's just short of being a La Ni&ntilde;a."
+ What about climate change?
+The latest global tropical cyclone season, which is just coming to an end, has been described as one of the worst in recent times, making it tempting to view Cyclone Larry as a product of human-related climate change.
+Grant Beard, a climatologist with the BOM's National Climate Centre, says the recent increase in intense tropical cyclones may be linked to warming. 
+"Looking at the globe ... it seems that the number of intense tropical cyclones has increased over the last 30 years," he says.
+"That's linked probably to the rising ocean temperatures and this is one sign of the enhanced greenhouse effect."
+Dr Kevin Walsh is associate professor of meteorology at the University of Melbourne and previously worked on the effect of climate change on tropical cyclones at CSIRO.
+He says climate change is likely to have some impact on cyclones, although this is yet to be proved.
+"All the projections say sea temperatures are warming and there are well known theoretical relationships between the warmth of the ocean and tropical cyclones," he says.
+"But it's controversial whether those effects have yet been detected."
+Love says only time will tell whether Larry is the product of climate change.
+"The jury's out," he says. "Any one event by itself doesn't prove or disprove anything."
+
+The artificial muscles work just like real ones, converting chemical energy into mechanical energy
+Artificial muscles have been made in the lab that are 100 times stronger than the real thing, a recent study shows.
+Two kinds of these super-strong artificial muscles can convert chemical energy into mechanical energy, making them function like natural muscles, the scientists say.
+Dr Von Howard Ebron and colleagues, from the NanoTech Institute at University of Texas at Dallas report their progress in the current issue of the journal Science.
+The artificial muscles could help usher in an entirely new breed of so-called fuel-cell muscles, the scientists say.
+These receive chemical fuel, such as hydrogen or methanol, through a circulatory system, convert it to mechanical energy, and store any unused energy for later. 
+Such muscles could be used to move robots and robotic exoskeletons, or as part of structures on air and marine vehicles that morph into different shapes. 
+"In the future, the humanoid robot sitting next to you at the bar may be drinking alcohol in order to work the next day," says Professor Ray Baughman, the research team leader and director of the NanoTech Institute. 
+One of the most successful kinds of artificial muscle consists of a stretchy material, which does not conduct electricity, sandwiched between two layers of material that do. 
+When an electric current is applied, the plus and minus charges accumulate on opposite layers of the sandwich. They are attracted to each other and squeeze down on the rubbery centre, giving the muscle its flexing ability. 
+A cord or batteries normally supply the power. But Baughman's team created two kinds of artificial muscles charged by a chemical reaction, eliminating the need for range-limiting power cords and bulky, short-lived batteries. 
+"The approach is not without challenges, but it could transform the way complex mechanical systems are built," writes Dr John Madden, an assistant professor at the University of British Columbia, in the same issue of the journal.
+Carbon nanotubes
+In the first approach, the scientists coated a sheet made of pure carbon nanotubes with platinum nanoparticles. They immersed the sheet into a solution of sulfuric acid. 
+A chemical reaction accelerated by the platinum catalyst converts each molecule of the hydrogen fuel to two protons and two electrons. 
+Repulsion between the electrons causes the nanotubes to expand. 
+In the second approach, the scientists used a special filament known as shape-memory wire, which can be trained to contract into a particular shape when heat is applied to it. 
+The team coated a straight memory wire with platinum nanoparticles and then exposed it to vapours from methanol mixed with air. 
+A chemical reaction occurred between the the alcohol and the oxygen in the air, which produced heat and caused the wire to contract. 
+Both types of muscles could be used in autonomous robots or as robotic armor worn by soldiers or astronauts to give them super-human strength, the scientists say. 
+Baughman imagines that the technology could eventually use sugars in the human body as fuel and enzymes instead of platinum to work one important artificial muscle: a heart.
+
+Female eastern whipbirds sing with a regional accent, which biologists say may be related to coordinating reproductive activities
+Female whipbirds in Australia sing the same basic songs, but with regional accents, researchers show.
+Female birds in general rarely sing, so this latest find itself is unusual.
+But the find is doubly noteworthy because the scientists observed that the males of this species, Psophodes olivaceus, sing with no accent whatsoever. 
+"It is so intriguing to see both of these opposite patterns occurring within the same species," says lead researcher Daniel Mennill, a professor of behavioural ecology at the University of Windsor in Canada. 
+"You wouldn't be shocked to visit one town and hear people speak with a twang, and then visit another town and hear a drawl," he says.
+"But can you imagine if, in your travels, you found that females sounded different in each town, but males had the same brogue? These whipbirds demonstrate such a pattern." 
+Mennill and his colleague Amy Rogers, from the University of Melbourne, measured eastern whipbird recordings from 16 different populations along the east coast of Australia.
+For each of the 112 birds they recorded, they measured the song's number of syllables, the length of the first syllable, the highest and lowest frequency of the last syllable, the time between these frequency extremes and other characteristics. 
+The vast majority of female recordings showed variations on each of these criteria, but male songs were all virtually identical. 
+The researchers publish their findings in a recent issue of the Journal of Avian Biology and post samples of the birdsong on their website.
+Cracking the whip
+In the wild, the males and females sing duets. Males initiate the duet with a long whistle and an ear-splitting 'whip crack'. Females then respond with a sharp 'chew chew'. 
+"In my opinion, the 'whip crack' sound might be the most extraordinary note produced by any beast in the animal kingdom," Mennill says.
+"It involves a pure tone that ascends or descends extremely rapidly across a very broad frequency spectrum. It is possible that this note is difficult to perform, and that females may favour males who are capable of executing this difficult note effectively." 
+While males must sing their hearts out for females, both males and females engage in their own same-sex singing contests.
+For these contests, usually each bird will perch itself near its territory boundaries. Birds then sing back and forth, trying to match the song sung by the opponent. Often the songs wind up overlapping.
+Interesting findings
+Peter Slater, a professor of natural history at the University of St Andrews in Scotland, agrees with the findings.
+"The real surprise here is the stereotypy [repetitive sameness] of the males ... In some other birds, females appear to choose mates on the basis that they perform a song that is quite hard to produce. I like the idea that the whip crack may be such a phenomenon and this might explain its very unusual stereotypy," Slater says.
+In terms of accents, he says that geographical variations, or dialects, are found in other songbirds, whales, seals and primates. 
+Mennill suggests that females may benefit by sharing songs that are similar to those of nearby females. While these benefits remain unclear, it is possible that the singing helps to somehow coordinate reproductive activities. 
+Male eastern whipbirds perhaps might have evolved accents too, if it were not for their impressive 'whip crack' song with its stunning finale.
+
+The technique may one-day be used to search earthquake rubble for survivors, the researchers say
+A laser-like beam of light shone at a unique solid makes the material appear to disappear, according to a new study. 
+The effect, reported in a recent issue of the journal Nature Materials, occurs at infrared light wavelengths, so it can't be seen with the human eye. 
+"[But] if it worked in the visible light with molecules that make up your hand, when the laser hit your hand, your hand would go transparent," says team member Professor Chris Phillips, a physicist at Imperial College London.
+"And then if you turned the laser up a little more, the scene you'd see through your hand would become brighter," as the effect amplifies light in the beam, he says. 
+Phillips and his colleagues from the University of Neuch&acirc;tel, Switzerland, think the method could one day work in visible light and lead to new technologies that help see through rubble to search for victims at a disaster site or observe internal body parts obscured by bone. 
+The scientists accomplished their feat with materials used to make semiconductor chips.
+Normally, electrons that make up atoms in these materials interact with light beams in a benign way. 
+But Phillips and his team re-engineered the material to contain artificial atoms, specially patterned crystals a few billionths of a metre long. 
+Because the atoms are artificial, the scientists could adjust the activity of the electrons, which have wavelike characteristics. 
+When the light beam was shone onto the material, it influenced the wavelike patterns of the electrons inside the artificial atoms so that they cancelled each other out and created a new, transparent material that was half matter and half light. 
+The scientists went on to amplify the light beam, even though 80% of the artificial atoms stayed in a state of so-called low excitation. 
+This contradicts a theory posed by Albert Einstein that says in order to amplify the light in a laser beam, the majority of the atoms must be in state of high excitation. 
+"They have shown this can now be implemented in a solid-state medium, which could be very important for more practical applications," says Lene Vestergaard Hau, professor of applied physics at Harvard University. 
+In the future, the researchers aim to become better at controlling and amplifying the light beam so that they may not need a specially patterned structure to make the see-through effect work.
+
+The 2002 launch: scramjet technology could one-day be used in planes that fly from London to Sydney in two hours, say the researchers
+A new scramjet engine, shaped like a bullet, will be tested in the Australian desert tomorrow by an international team of scientists that hopes it will be more efficient than previous designs.
+Australian researchers from the HyShot Flight Program at the University of Queensland, will test the new scramjet, developed by a British defence technology company, QinetiQ.
+The experiment is to be carried out on Australian defence property at Woomera in South Australia this Friday local time and is also sponsored by the US Air Force and the Canadian Air Force.
+A scramjet (supersonic combustion ramjet) operates at speeds greater than Mach 5, or five times the speed of sound. 
+It is able to deliver a sustained thrust at hypersonic speed by rapidly sucking in oxygen and burning hydrogen fuel, releasing steam as exhaust.
+The HyShot team carried out the world's first successful scramjet test flight at Woomera in 2002 with a University of Queensland-designed engine.
+That original design had a two-dimensional wedge-shaped air intake and a rectangular-shaped combustor, says Associate Professor Michael Smart, who designs scramjets with the HyShot team.
+He says the new scramjet has a three-dimensional bullet-shaped intake with an elliptical shaped combustor.
+And the shape of the engine affects how efficiently air is scooped up.
+"It's a ram effect and there are lots of different shapes you can use to try to push that air down through the engine, so we're just trying out different ones," he told ABC Science Online by phone from the Woomera test site.
+
+The H5N1 bird flu virus doesn't lock onto the right receptors in humans, says new research
+Virologists say they understand why bird flu in its present form does not spread among humans.
+The finding suggests the world may have a precious breathing space to prepare for any flu pandemic. 
+The reason lies in minute differences to cells located in the top and bottom of the airways, the team reports in today's issue of the journal Nature.
+To penetrate a cell, the spikes that stud an influenza virus have to be able to bind to the cellular surface. 
+The virus spike is like a key and the cell's docking point, called a receptor, is like a lock. They both have to be the right shape for the connection to happen. 
+Scientists in the US and Japan, led by Professor Yoshihiro Kawaoka of the University of Wisconsin at Madison, found that avian influenza viruses and human influenza viruses home in on slightly different receptors.
+The receptor preferred by human flu is more prevalent in cells in the mucous lining of the nose and sinus as well as the throat, trachea and bronchi.
+But the receptor preferred by bird flu tends to be found among cells deep in the lung, in ball-like structures called the alveoli. 
+It means H5N1 is likely to hole up in a part of the airways that does not cause coughing and sneezing, the means by which the flu virus is classically transmitted among humans.
+Birds infecting humans
+Bird flu is lethal to poultry and dangerous for humans in close proximity to infected fowl. It has claimed more than 100 lives, according to the World Health Organization. 
+But, apart from a few anecdotal cases, the mortality has occurred exclusively by direct transmission from birds to humans and not among humans themselves. To acquire that contagiousness would open the way to a pandemic. 
+"Our findings indicate that H5N1 virus ... can replicate efficiently only in cells in the lower region of the respiratory tract, where the avian virus receptor is prevalent," the paper says. 
+"This restriction may contribute to the inefficient human-to-human transmission of H5N1 viruses seen to date." 
+So what would turn H5N1 into a pandemic virus?
+First and foremost, it would need mutations in the spike, the haemagglutinin molecule, to enable the virus to bind to cells in the upper respiratory tract. 
+This would enable the virus to spread via coughs and sneezes and nasal mucus, which are caused by irritation to the upper airways. 
+To boost its pandemic potential, the virus also needs changes in its PB2 gene, which controls an enzyme essential for efficient reproduction. 
+"Nobody knows whether the virus will evolve into a pandemic strain, but flu viruses constantly change," says Kawaoka. 
+"Certainly, multiple mutations need to be accumulated for the H5N1 to become a pandemic strain." 
+The findings suggest scientists and public health agencies may have more time to prepare for an eventual pandemic of avian influenza, the team believes. 
+Kawaoka's team exposed various tissues from the human respiratory tract to a range of viruses in lab dishes. 
+The viruses were the human strains H1N1 and H3N2 and the bird strains H3N2 and H4N6. In addition, there were two H5N1 samples, one taken from a human victim in Hong Kong and one from a duck in Vietnam. 
+Flu viruses reproduce sloppily, which induces slight changes in their genetic code. This movement is called antigenic drift, and explains why seasonal flu viruses keep changing and new updated vaccines are needed. 
+But they can also make big changes, called antigenic shift, in which new genes are brought in, thus creating a new pathogen against which no one has immunity. A novel flu virus that emerged after World War I killed as many as 50 million people. 
+By closely monitoring viruses from people infected with avian flu, scientists can get a early warning as to whether these strains are mutating into forms that will make it easier to fit into human receptors, Kawaoka says.
+
+The headaches, colds and sniffles associated with 'sick building syndrome' are more likely a sign of poor work satisfaction, a new study shows
+So-called sick building syndrome does not exist, according to a UK study that suggests its cold-like symptoms can be mainly pinned to job stress, dissatisfaction and poor office relationships.
+Dr Mai Stafford, of University College London, and colleagues publish their findings today in the journal Occupational and Environmental Medicine.
+The research is part of the prestigious Whitehall study, a wider body of work looking at the health of public servants.
+Sick building syndrome is a popular yet vague term to describe headaches, coughs, tired or itchy eyes, runny noses or inexplicable tiredness that are usually blamed on poor air quality in the office.
+More than 4000 UK public servants, aged 42-62 and working in 44 different buildings across London, were questioned about their health. 
+They were asked to list any symptoms of sick building syndrome, the physical properties of their offices and the demands of their job, including levels of support at work. 
+Separately, the buildings were also assessed by independent field workers. 
+They checked temperature, lighting intensity, levels of airborne bacteria, fungi and dust, humidity, ventilation flow, noise level and concentrations of CO2 and airborne organic chemicals. 
+One in seven of the men and nearly one in five of the women respondents reported five or more symptoms of the syndrome. 
+Hot, dry and dusty
+There was some evidence, but minor, that those who reported high levels of the symptoms worked in offices that were too hot and dry and had relatively high levels of airborne germs and dust. 
+But those with only low levels of the symptoms worked in buildings where there was poor air circulation and unacceptably high levels of CO2, noise, fungus and airborne chemicals. 
+In fact, the biggest factors linked with the symptoms were job stress and lack of support in the workplace.
+"'Sick building syndrome' may be wrongly named," say the authors. 
+"Raised symptom reporting appears to be due less to poor physical conditions than to a working environment characterised by poor psychosocial conditions." 
+A long line of research
+Previously research has highlighted a link between ill health and control over work, job demands, work overload and job category. 
+If sick building syndrome may not exist, its symptoms do, and they cost companies dearly in lost production, the paper says.
+It says the lesson for bosses is that when such symptoms come to light, they should consider causes that go beyond the office's physical design and operation and delve into more complex areas, such as job roles and the autonomy of the workforce.
+
+Dissolving CO2 deep in the oceans needs to be considered, says a German expert who is calling for more research
+Pumping carbon dioxide into the oceans may be one way to help save us from global warming, says a chemical engineer who admits the subject is "taboo".
+Professor Wolfgang Arlt, who has been visiting Australia's Swinburne University of Technology in Melbourne, says governments see this so-called ocean sequestration as too politically risky, compared to geosequestration, when CO2 emissions are buried underground.
+Since ocean sequestration was first proposed 20 years ago, Arlt says it has been the subject of relatively little research, and he is calling for more.
+"I want to have every option equally researched," he says, emphasising that reduction of CO2 emissions is the first priority before any form of sequestration.
+Alrt, who is based at the University of Erlangen-Nuremburg in Germany, stresses he is not supporting ocean sequestration, only its investigation as an option to help stop global warming.
+Arlt's speciality includes the science of separating different chemicals such as CO2 and air and he calls ocean sequestration "the natural option".
+"Nature does it already," he says. "If you look at our total emissions of carbon dioxide, one part is stored in the air, and the other part is dissolved in the ocean."
+The oceans are Earth's main buffer system, he says.
+He says increased concentration of CO2 in the atmosphere has led to increased amounts of the gas dissolved in the surface of the ocean and this in turn has led to an increase in ocean acidity that is harmful to marine life.
+Going deeper
+But, says Arlt, his initial calculations suggest ocean sequestration does not have to significantly increase the acidity of the oceans as long as the CO2 is injected deep into the ocean and is mixed across the whole planet.
+Arlt says CO2 can be injected into "down-welling" areas of the ocean and, in its dissolved form, will tend to stay at the bottom of the ocean where it can then be mixed by deep ocean currents across the planet.
+He says one modelling exercise suggests CO2 injected near Europe will be distributed as far as Australia in 100 years time.
+Arlt says he predicts that the effect on ocean acidity using this method would be so small it would be unmeasurable, and would not affect sea life on the ocean bottom. But he thinks this should be investigated further.
+He says another option is to neutralise the CO2 before sequestering it in the oceans by mixing it with alkaline minerals such as limestone.
+IPCC warns on ocean acidification
+A recent report on CO2 capture and storage from the Intergovernmental Panel on Climate Change (IPCC) canvasses options for ocean sequestration but does not include Arlt's argument.
+The report says ocean sequestration could help lock up CO2 for hundreds of years, with deeper injection being more effective than shallower injection.
+But it warns increased acidity at the ocean surface can harm marine organisms.
+The report does not mention Arlt's point about down-welling waters and deep ocean currents.
+Alrt says the IPCC had wanted him to co-author the report, but because of time problems he did not contribute. 
+"So my ideas are not inside the report," he says.
+The IPCC report notes that the effect of increased CO2 in the deep ocean has yet to be studied.
+Whole range of options
+An Australian co-author of the IPCC report, Dr Peter Cook, chief executive of the Co-operative Research Centre for Greenhouse Gas Technologies, agrees little is known about ocean sequestration and more research is always good.
+"We're going to need the whole range of options for decreasing CO2 emissions," he says.
+But he says the IPCC took a "very cautious view" about the future of ocean sequestration.
+"We have to be very careful about doing it before we have a great deal more information," Cook says.
+
+Drainage from the southernmost dome of Greenland
+Polar ice sheets are melting faster than expected and could push sea levels up as much as 6 metres by 2100, scientists warn in two studies released today.
+Based on current warming trends, they say, average temperatures could jump at least 2.5&deg;C by the end of the century, resembling the last great global warming surge 129,000 years ago when seas rose as much. 
+Professor Jonathan Overpeck of the University of Arizona and Dr Bette Otto-Bliesner of the National Center for Atmospheric Research, co-wrote both studies, which appear in the latest issue of the journal Science.
+They used a computer model for future climate predictions and ice sheet simulations to create a picture of the Earth's climate 129,000 years ago. 
+They also used climate-indicative data from sediments, fossils and ice cores. 
+They conclude that the melting of ice sheets in Greenland and in the Antarctic today resembles what happened back then, and that the risk of a comparable rise in sea level is high. 
+"Although the focus of our work is polar, the implications are global. These ice sheets melted before and sea levels rose. The warmth needed isn't that much above present conditions," Otto-Bliesner says. 
+Dynamic maps of the projected results of the rise in sea levels are available on Overpeck's website.
+Call for action
+Overpeck says we need to act soon.
+"We need to start serious measures to reduce greenhouse gases within the next decade. If we don't do something soon, we're committed to 4-6 metres of sea level rise in the future," he says. 
+A conservative estimate would call for sea level rises of 1 metre per century, he says.
+He cautioned, however, that this estimate assumes the Earth will get only as hot as it did 129,000 years ago when the ice sheets melted. 
+The earlier ice melt was concentrated in the Northern Hemisphere in the summer months, and was due largely to changes in Earth's orbit, he says. 
+"The climate warming we're in now is global and it's year-round and it's due to human influences on the climate system," he says.
+"That will be more damaging to the ice sheets than the that warming we had 130,000 years ago." 
+The ice sheets are already melting, accelerated by relatively warm water that eats away at them, says NASA glacier expert Dr Bob Bindschadler.
+"It's not really a debate any more about whether sea level is rising or not. I think the debate has shifted to, how rapidly is sea level rising," he says.
+
+The research behind the 2006 Abel Prize for maths explains how violin strings vibrate
+The world's most prestigious maths prize has been awarded to a Swedish researcher for his work on wave patterns.
+Professor Lennart Carleson of the Royal Institute of Technology in Sweden was awarded the Abel Prize for maths for his work on the Fourier series.
+This says that everything from the vibration of violin strings to the spread of heat through a metal bar can be viewed as sums of simple wave patterns, oscillating sine and cosine waves.
+This led to the branch of maths known as harmonic analysis.
+He also solved the so-called corona problem, which looks at structures that show up around a disc when the disc itself is hidden.
+An example might be the corona of the Sun seen during an eclipse, when it's hidden by the Moon.
+The prize, which is awarded by the Norwegian Academy of Science and Letters, is often described as the 'Nobel' prize for maths.
+The prize rules say it should aim to spur interest in mathematics among children and young people. So far, all winners of the prize have been in their 70s.
+
+This pattern of spirals was made using a computer that analysed someone's voice
+An Australian digital artist is using his voice to design textiles.
+Pierre Proske has developed computer software that translates different frequencies in someone's voice into spiral patterns, producing what he calls 'voiceprints'.
+Proske developed the software while doing his masters in art and technology at Sweden's IT University of Göteborg.
+He's used the software to design a pattern inspired by elements of Japanese textiles, a design that appeals to him because of its simple repeated elements.
+"Computer code is very simple and minimalistic, you have these ones and zeros, so I thought it would be good to choose a very minimalistic textile as well."
+The textile is made up of repeated spirals of more or less the same size in a particular dense and fairly regular arrangement (see image below). 
+Proske then scanned one of the spirals into his computer as the basic element in his voiceprint design.
+Next he used the software to analyse the frequency profile of a short sample of a voice.
+"You might get a bunch of low frequencies and some high frequencies depending on what you say and how you say it," he says.
+The software translates the relative amounts of different frequencies of a particular sound into a particular layout of spirals of different sizes.
+Different voice sounds can create different layouts of the spirals, says Proske.
+He says the software could be used to generate patterns for textile and graphic design.
+"The idea is that it is actually meant to be quite accessible. Anybody could use their voice to generate these patterns."
+Proske sees his research as a modern take on old technologies.
+"I'm kind of inspired by the connection of textiles and computers because they have a historical link that goes back to the automation of the loom in the 1800s," he says. 
+Proske says the same punched cardboard cards used to code for textile patterns were later used to program the first computers.
+
+Chocolate may give you short-term pleasure if you crave it. But it's not an antidepressant, as many people think
+Chocoholics can happily eat chocolate for pleasure, but for those who are stressed and clinically depressed, the high is short-lived and chocolate may even deepen the downer, a review shows.
+The findings, which will be published in the Journal of Affective Disorders, fly in the face of the myth that chocolate is an antidepressant.
+The analysis, which is the most comprehensive literature review on how chocolate affects mood, shows that the motivation behind eating chocolate determines which neurotransmitters are activated, and hence your mood.
+The review's Australian authors, from the Black Dog Institute at the Prince of Wales Hospital in Sydney, identified two groups of chocolate eaters based on motivation.
+They identified the cravers, who eat chocolate as an indulgent pleasure, and the emotional eaters, who use chocolate in a bid to alleviate depression.
+Professor Gordon Parker, executive director of the Black Dog Institute and lead author, says cravers see chocolate like a good glass of wine, and anticipating and eating the treat releases 'feel good' neurotransmitters. 
+"Chocolate craving as an indulgent pleasure seems to stimulate the dopamine system in the brain, and provides an enjoyable experience," he says.
+"But the emotional eaters, people who eat chocolate to relieve boredom, stress or clinical depression, are looking for an opioid effect to improve their mood."
+For them, at best chocolate only provides temporary relief, he says. But this is quickly followed by a return to or a worsening of their earlier negative state.
+Consuming sweet foods is thought to release the neurotransmitter beta-endorphin in the hypothalamus, which is said to have an opiate effect on the body. 
+But why the chocolate high is so transient and insufficient to sustain mood in those who eat it for emotional reasons remains unknown. 
+Busting the myth
+The theory that chocolate acts as an antidepressant comes from the common belief that a serotonin deficiency causes chocolate cravings, but the review found no support for this hypothesis.
+"It is true that chocolate acts on the same neurological system as serotonin. But you'd have to eat a truck load of chocolate before you have had the equivalent of one antidepressant tablet," Parker says.
+"Our review rejects any possibility that chocolate desired as a way of relieving stress or when feeling down has any antidepressant benefit."  
+Stimulants such as caffeine, theobromine, tyramine and phenylethylamine, are also present in concentrations too low to have any significant psychoactive effect, the review says.
+For more information about depression, including fact sheets, support and referrals, see the websites for beyondblue, Australia's national depression initiative, and depressioNet.
+
+If this research applies to humans, scientists might have another source of stem cells
+Scientists have isolated sperm-producing stem cells from adult mice that have similar properties to embryonic stem cells.
+If the same type of cells in humans show similar qualities the German researchers believe the cells could be used in stem cell research.
+This would remove the ethical dilemma associated with stem cells derived from human embryos. 
+"These isolated spermatogonial stem cells respond to culture conditions and acquire embryonic stem cell properties," say Professor Gerd Hasenfuss and his colleagues from the Georg-August-University of G&ouml;ttingen online in the journal Nature. 
+Stem cells are master cells that have the potential to develop into any cell type in the body.
+And some scientists believe they could act as a type of repair system to provide new therapies for illnesses ranging from diabetes to Parkinson's. 
+But their use is controversial because some scientits say the most promising stem cells for treating human disease are derived from very early human embryos left over from fertility treatments.
+In the report Hasenfuss and his team describe how they isolated the sperm-producing stem cells from mice testes.
+The cells, which they call multipotent adult germline stem cells, under certain conditions, act like embryonic stem cells. 
+When the researchers injected the cells into early embryos they found the cells contributed to the development of different organs. 
+Intruiging, but more work needed
+Professor Chris Higgins, the director of the UK's Medical Research Council Clinical Sciences Centre, says the possibility of using the cells as an alternative to embryonic stem cells for therapy is intriguing.
+"However, much more research is required before the similarities and differences between these testes cells and embryonic stem cells are understood, and before their potential for use in therapy can be properly assessed," he says.
+Dr Stephen Minger, a stem cell biologist at Kings College London, describes the findings as "pretty amazing" but says more research is needed. 
+"We would need to replicate this in humans, just because it works in a mouse doesn't necessarily mean it will also work in people," he says.
+
+Chatting on a mobile phone before sleep affects the electrical activity of your brain
+Radiation from mobile phones stimulates brain activity in the early stages of sleep even after you've finished using the phone, an Australian study shows.
+Associate Professor Andrew Wood from the Brain Sciences Institute at Melbourne's Swinburne University says his study also found that exposure to electromagnetic radiation from mobile phones can reduce levels of the hormone melatonin, which is connected to the body's sleep-wake cycle.
+But the study, reported in the International Journal of Radiation Biology, says it's premature to conclude that talking on your mobile phone before bed will get in the way of a good night's sleep.
+Alpha waves
+The study's 55 participants received 30 minutes of mobile phone radiation, or 30 minutes of 'sham' radiation, on successive Sunday nights before being tucked into bed.
+Wood found that exposure to mobile phone radiation resulted in heightened alpha-wave activity in the brain. Alpha waves are associated with relaxation and daydreaming but normally disappear with sleep.
+"We found that in the first hour or so after getting to sleep that there was a significant change in one of the parameters of brain activity, that is the amount of alpha waves in the brain wave patterns," he says.
+The increase occurred in the first non-REM period of the night, when subjects had drifted off but before they were in deep sleep.
+Australian sleep specialist Professor Leon Lack, from Flinders University in Adelaide, says this could be a sign that the first non-REM period of sleep isn't as efficient as it could be, leaving people feeling tired when they wake up.
+"Alpha waves are really only present when you're lying awake with your eyes closed trying to fall asleep," he says.
+"If they are occurring during what would normally be sleep stages [it could be] the intrusion of some sort of wakeful brain activity at a time when it shouldn't be there."
+Melatonin 
+Researchers also tested participants' urine for markers of the hormone melatonin, which is produced in the evening and is associated with individual sleeping and waking rhythms.
+Wood says some participants had an increased amount of melatonin after exposure, although there was no overall increase.
+"Some people had significantly less of this melatonin marker in their urine before they went to bed but overall the amount of melatonin didn't change," he says.
+He says the difference was quite marked in some people, indicating there may be "a special subgroup of the population that are susceptible to the effects of mobile phone radiation".
+Lack says melatonin's role in sleep is unclear and it's uncertain whether having more or less affects your sleep.
+Wood says that at this stage mobile phones don't seem to influence how well you sleep, unless the phones ring at all hours or you've had a particularly exciting conversation.
+"If people are finding they can't sleep after using mobile phones often it's the content of what they've been talking about that's the reason they can't sleep," he says.
+
+Humpback whales have structured songs, with phrases and themes. But no-one knows what they mean
+Humpback whales sing songs that contain elements of human language, according to a detailed new analysis of whale songs recorded in Hawaii.
+While researchers do not yet believe that whales have their own language per se, they discovered striking similarities between human language and the songs of humpback whales (Megaptera novaeangliae). 
+Lead researcher Ryuji Suzuki says that both humans and whales communicate by using discrete sound units that are arranged within a hierarchical structure. 
+"For example, a text consists of paragraphs, a paragraph consists of sentences, a sentence consists of clauses etc," says Suzuki, at the Massachusetts Institute of Technology.
+"They are at different levels of hierarchy, or layers.
+"In terms of humpback songs, a song session consists of songs, a song consists of themes, a theme consists of phrases, a phrase consists of units." 
+Put together, all of these elements indicate that whales have something akin to their own syntax, which normally refers to the grammatical arrangement of words within sentences. 
+The findings are published in this month's Journal of the Acoustical Society of America. 
+Suzuki and colleagues designed a computer program that converted tiny sections of whale songs into mathematical symbols. 
+They then analysed the average amount of information that was conveyed for each symbol with a technique called information theory, which quantifies complexity and structure. 
+"Information in the context of information theory does not include 'meaning', but it focuses on how rare, surprising, predictable or complex a message is," Suzuki explains. 
+Listening to whale song
+Human observers who had no previous knowledge about whale song structure grouped humpback whale recordings into complexity, redundancy and predictability. 
+The computer analysis and the human observers all found that whale songs are not only hierarchical, they convey around one bit of information per second. 
+By comparison, humans generate 10 bits of information, or variance, for every word that is spoken. 
+Each spoken vowel or syllable, for example, contains at least a few bits of data that correspond to different sounds produced by the speaker. 
+One versus 10 may not sound very impressive, but whales communicate in water, often over long distances. Water helps to transmit songs because it carries sound four times faster than air. 
+Using information theory
+Jennifer Miksis-Olds, a research associate at the University of Massachusetts at Dartmouth's School for Marine Science and Technology, is one of the few people in the world who is also using information theory to study whale songs. 
+"I do agree with the new findings. I am currently using information theory to analyse humpback whale communication, and I have come to similar conclusions," Miksis-Olds says.
+She agrees that marine mammal songs and sounds cannot be classified at present as language, but both she and Suzuki admit that they do not yet understand the meaning of whale songs and that more research is needed. 
+"This is what we know [so] little about," Suzuki says. "[Humpback whale] singers are always male, and song is believed to be a mating display. The song type evolves over the mating season, and all animals in the same population seem to share the same song type, that is, humpback whales somehow copy each other's song.
+"However, the details of this are unknown. What the songs mean is, again, unknown."
+
+Combining alcohol with an energy drink makes you feel sober enough to drive even though you're over the limit, new research shows
+People who combine energy drinks with alcohol can feel more sober than they truly are, a new study suggests. 
+Brazilian researchers found that young men were no less impaired when they drank a mix of alcohol and a popular energy drink than when they downed a standard mixed drink. 
+But drinkers seemed to think they were less drunk. 
+According to research in the April issue of the journal Alcoholism: Clinical & Experimental Research, the drinkers reported less fatigue, fewer headache symptoms and better coordination.
+This is concerning because people who mistakenly think they are less impaired can be a danger to themselves and others, according to study co-author Dr Maria Lucia Souza-Formigoni. 
+"I think people should be aware of this effect of the combination. They feel better but they are not 'good enough' to drive, for instance," says Souza-Formigoni, an associate professor at the Federal University of Sao Paulo.
+Energy drinks typically consist of carbohydrates, B vitamins, caffeine and taurine, a derivative of an amino acid found in animal tissue. 
+Some studies have shown that the beverages, or their main ingredients, may improve mood and physical performance.
+And there's a popular, though unproven, belief that mixing energy drinks with alcohol can counter some of the effects of drinking. 
+This new study suggests that while energy drinks may help drinkers feel less tipsy, they are still in fact drunk.
+Mixing your drinks
+The study included 26 young men who each took part in three separate experiments: one in which they drank vodka mixed with an energy drink, another in which they had vodka mixed with fruit juice, and a third where they drank only the energy drink. 
+In general, the researchers found that the men reported fewer headache symptoms and less weakness with the energy drink-alcohol mixture compared with the standard mixed drink. They also thought their hand-eye coordination was sharper. 
+But the men performed no better on objective tests of hand-eye coordination and reaction time to visual cues. 
+One of the dangers of this effect, according to Souza-Formigoni and her colleagues, is that drinkers, especially young ones, may feel free to drink more than they might otherwise have. 
+Depressive effects on the brain
+It's not clear, Souza-Formigoni says, why study participants feel less drunk when they had the energy drink even though they were still objectively impaired.
+But in animal research, she and her colleagues have found that some energy drinks ingredients, mostly caffeine and taurine, may counter some of the depressive effects alcohol has on the brain. 
+The findings in humans, however, suggest that's not enough to avoid becoming drunk.
+
+Astronomy, physics, biology, architecture and inventing. Dr Robert Hooke tried them all. Seen here, a page from his Micrographia, a study of biological specimens viewed through a microscope he made himself
+A manuscript charting the birth of modern science, lost for more than 200 years, goes on sale this week.
+The journal of Dr Robert Hooke has been hailed as 'science's missing link' and has a price tag equivalent to about A$2.4 million (US$1.7 million).
+It contains details of experiments Hooke conducted as curator at the UK's Royal Society from 1662 and his correspondence as its secretary from 1677. 
+The notes include a celebrated row between Hooke and Sir Isaac Newton over planetary motion and gravity, and the lost record confirming the first observation of microbes by Antoni van Leeuwenhoek.
+Hooke was a keen observer of nature with a fascination for things mechanical but, because of ill health as a child, he was initially left largely to educate himself. 
+A talented artist, he was sent to London when his father died to study under leading portrait painter Peter Lely.
+He went on to study first at Westminster School and then Christ College, Oxford where he won a place as a chorister. 
+There he studied astronomy, tried his hand at mechanical flight and rubbed shoulders with top scientists of the day.
+A meeting of these scientists in November 1660 founded the Society for the Promoting of Physico-Mathematical Experimental Learning, which in mid-1662 received a royal charter and became the Royal Society of London.
+Biologist, astronomer, physicist
+In 1665 Hooke finally found fame with publication of his Micrographia containing pictures of objects he had studied through a microscope he had made himself, and a number of biological discoveries. 
+Diarist Samuel Pepys said of the book that it was the most ingenious he had ever read. 
+But his talents did not stop there. 
+Hooke discovered that Jupiter revolved on its own axis, suggested that gravity could be measured using a pendulum.
+Architect, inventor
+He was also a talented architect and was chief assistant to Sir Christopher Wren in rebuilding London after the Great Fire of 1666. 
+He also suggested the presence of gravitational 'vortices' pulling comets from their orbit, and invented the reflecting telescope, the sextant, the punched-paper record-keeper, the wind gauge, the worm gear and the wheel barometer.
+But he fell out with Newton when he accused him of stealing from his original ideas when he produced his theory of light and colour in 1672, and Newton removed all reference to Hooke from his famed Principia.
+Hooke's law
+Despite Hooke's huge contribution to science and understanding, the only innovation to bear his name is Hooke's law, which says that the extension of a spring is proportional to the force applied. 
+Hooke died in London in March 1703 aged 67.
+Experts from an auction house found his journal by chance in a cupboard at a private house in Hampshire during a routine valuation.
+
+Researchers have developed a working interface between living tissue and silicon chips
+European researchers have 'glued' live nerve cells onto a silicon chip and managed to get the neurones and chip to talk to each other.
+The technology, which used networks of rat neurones grown in culture, could lead to the creation of 'neural prostheses' or the creation of 'organic computers' powered by living neurones, the team says.
+The Italian, German and Swiss team says it took a lot of effort to develop a working interface between the living cells and the chip's inorganic compounds.
+"We attacked the problems using two major strategies, through the semiconductor technology and the biology," says molecular biologist Professor Stefano Vassanelli from the University of Padua.
+The team, which is being funded by the European Commission's Information Society Technologies program, put 12,384 transistors and hundreds of capacitors on a 1 millimetre square chip.
+Then the reserearchers used proteins found in the brain to 'glue' the neurones to the chip, Vassanelli says.
+The proteins also act as a link between the ion channels of the neurones and the semiconductors, allowing neural signals to be passed to the chip.
+In the opposite direction, the chip's capacitors stimulated the neurones, causing them to 'fire'.
+Vassanelli says the team's next project is to work out how chips could communicate with genes and vice versa.
+"Genes are where memory comes from and without them you have no memory or computation," he says.
+"We want to explore a way to use genes to control the neurochip."
+Keeping neurones alive
+Professor Ashley Craig, an Australian neuroscientist with the University of Technology, Sydney, says linking computer circuits with brain cells can kill neurones by interfering with the brain's fragile chemical and electrical balance.
+And linking chips with genes may be an option.
+Commenting on the European proposal, he says targeting genes instead would enable the chip to communicate with a network of cells.
+"Genes contain the memory and knowledge of building things, growth and regrowth," he says.
+"They would target a particular gene, maybe heart disease or addiction, and link it to a computer chip tucked away under your skin, and try and influence [gene communication]."
+
+Scientists have thought of using soil microbes to break down styrofoam into a useful byproduct
+Bacteria that break down styrofoam into 'green' byproducts could be used to make a new kind of biodegradable plastic, new research suggests.
+The method could help reduce the tonnes of petroleum-based plastic waste that makes its way into landfills each year, says Irish research leader Dr Kevin O'Connor, who heads the bioplastic research group at University College Dublin.
+O'Connor and his team's research results will appear in the 1 April issue of the journal Environmental Science and Technology. 
+Scientists have already used microorganisms to break down the kinds of chemical products found in styrofoam.
+But no-one has created a useful plastic byproduct, says Dr Manfred Zinn, a research group leader at EMPA, the materials science and technology lab of the Swiss Federal Institute of Technology. 
+To convert the plastics, O'Connor's team used a strain of soil bacteria known as Pseudomonas putida. 
+In nature, this microorganism lives in the ground, where it feeds on the carbon, nitrogen, hydrogen, and oxygen found in organic matter such as dead plants. 
+Styrofoam, a material made from polystyrene, contains hydrogen and carbon, but not in a form that the bacteria can readily digest. 
+To make the plastic edible, the scientists had to heat it under the process of pyrolysis, which melted the polystyrene at very high temperatures in an oxygen-free environment to break the chemical bonds. 
+No oxygen means no burning and so no emissions. During the process, the polystyrene became liquid styrene, a carbon-based compound that the bacteria can eat. 
+In the lab, the scientists created a growing environment for the bacteria, feeding them all their favourite foods, including nitrogen and oxygen. 
+A steady flow of styrene oil supplied to the bacteria in a fermentor allowed the bacteria to proliferate. 
+After the colony grew to a healthy size, the scientists stopped feeding the bacteria nitrogen. That stimulated the bacteria to begin storing the carbon for use later. 
+Storing carbon is the key
+It turns out that when the bacteria store the carbon, they convert it into a plastic known as polyhydroxyalkanoate, or PHA. 
+PHA is made up of fatty acids that are easily attacked by the bacterial enzymes.
+"PHA is a 100% biodegradable plastic that can be thrown on your compost heap. Bacteria in the compost heap use the plastic as food to grow, so there is no damage to the environment. You can't get greener than that for a plastic," says O'Connor. 
+The compound can also be harvested from the bacteria to make biodegradable plastic goods such as shampoo bottles, credit cards, and medical implants and devices, all of which will fully degrade in the garbage, says O'Connor. 
+"This is a great opportunity to make something better from a recycled material," says Zinn. 
+O'Connor and team know that worldwide, more than 14 million tonnes of polystyrene are produced annually, but are unsure how much investment it would take to build a plant capable of converting the material into PHA. 
+But he says the process works on any petrochemical plastic waste and that fact could open up new areas of exploration for the petrochemical industry.
+
+Total solar eclipse, as seen in 2002
+It has been called the Sun-eating dragon, the spirit of the dead and the eye of God. 
+It has been a harbinger of great events, good and evil - famines, bumper harvests, wars, and the birth and death of kings.
+Later today, we'll know it as the total eclipse of the Sun, when the Moon will be perfectly aligned with our star, and the lunar shadow will alight on the tip of eastern Brazil.
+Racing eastwards across the Atlantic, the umbra will reach the coast of Ghana, then head across Togo, Benin, Nigeria, Niger, Chad, Libya, where the eclipse will be at its longest, lasting 4 minutes, 7 seconds, and then northwestern Egypt.
+It will then zip across the Mediterranean, passing between Crete and Cyprus before making landfall in Turkey, traversing Georgia, southern Russia and then in Kazakhstan. 
+The shadow briefly crosses Russia again before expiring at sunset in Mongolia after a marathon of 3 hours, 12 minutes and 14,500 kilometres.
+Around 2500 kilometres either side of this path of totality, observers will get a partial eclipse. For instance, about a fifth of the Sun will be obscured in the UK, southern Sweden and the southern Gulf. 
+Australia is among countries unable to see the eclipse. But ABC Science Online brings you photos, videos and commentary of the event as seen from Turkey.
+See Chasing the Sun in Turkey for more information.
+Far back in time
+Eclipses are infrequent events, and their rarity is enhanced by the fact that most take place over the ocean, which covers two-thirds of the world's surface, and so they go unwitnessed except by seafarers and remote islanders.
+But writings dating back to the dawn of civilisation testify to thrill and dread as the Sun, the bringer of life, was gradually blotted out, the stars appeared in an indigo sky, the terrified birds stopped singing and bats left their roost. 
+"Nothing can be surprising any more, or impossible or miraculous, now that Zeus, father of the Olympians, has made night out of noonday, hiding the bright  sunlight, and ... fear has come upon mankind," wrote the Greek poet Archilochus after an eclipse in 648 BC. 
+"After this, men can believe anything, expect anything. 
+"Don't any of you be surprised in future if land beasts change places with dolphins and go to live in their salty pastures, and get to like the sounding waves of the sea more than the land, while the dolphins prefer the mountains." 
+For the ancient Chinese, the eclipse was a Sun-eating dragon, which had to be scared away by the banging of cymbals and pans.
+For the Vikings, it was caused by two chasing wolves, Skoll and Hati. Hindu mythology blames a demon called Rahu who spitefully takes a bite out of the Sun from time to time. 
+Even today, in some cultures, eclipses are believed to bring poisonous vapours and so food and water containers are turned upside-down in protection. 
+Watching and waiting
+The most-observed solar eclipse took place in 1999, when the path of totality crossed major population centres in Europe, the Middle East and Asia. 
+This year, no big city lies directly on the 185 kilometre-wide path, although several, including Ankara, Lagos and Tbilisi, lie very close to it and will get a near-total eclipse. 
+The luckiest of all are people who inhabit the mountains of central Turkey, says NASA's veteran eclipse specialist, Dr Fred Espenak. 
+"A quarter million people in Sivas have the opportunity of witnessing a second total eclipse from their homes in less than seven years," he says.
+
+In clever kids, the brain's cortex or outer mantle thickens rapidly during adolescence
+Intelligence may have more to do with how the brain develops during adolescence than its overall size, researchers say.
+US scientists at the National Institutes of Health show that the brains of children with high IQs show a distinct pattern of development. 
+The cortex, or outer mantle of the brain, starts out thinner and thickens more rapidly in very intelligent children. It peaks around 11 or 12 years old before thinning rapidly in the late teens.
+"We found that the cortex showed a different pattern of development," says Dr Philip Shaw, lead author of the research published today in the journal Nature.
+Youngsters with average IQs have a thicker cortex to start with and peak earlier before gradual thinning begins. 
+Shaw adds that the changes are subtle and what is driving them is a mystery. Why children have a thicker or thinner cortex initially is also not known. 
+"Brainy children are not cleverer solely by virtue of having more or less grey matter at any one age," says Dr Judith Rapoport, a co-author of the study. 
+"Rather IQ is related to the dynamics of cortex maturation."
+The scientists took magnetic resonance imaging scans of 307 healthy children and teenagers, aged 5-19, every two years as they grew up. 
+They compared the scans to see how they related to the children's IQ. Very intelligent youngsters had scores of 121-145 while high IQs were between 109-120 and average between 83-108. 
+The smartest youngsters showed the highest rate of change in the scans. The scientists believe the longer thickening time in the very brainy children might indicate a longer period for the development of high-level cognitive circuits in the brain. 
+The researchers add that the thinning phase could involve a "use it or lose it" pruning, or killing off, of brain cells and their connections as the brain matures and becomes more efficient. 
+"That might be happening more efficiently in the most intelligent children," says Shaw. "People with very agile minds tend to have a very agile cortex."
+
+Astronomers have found mid-sized moonlets embedded in Saturn's rings. But that doesn't fit with current models of how the rings formed
+Minute moons just a hundred metres or so across orbit Saturn within its rings, astronomers report, a finding that questions how the planet's majestic ring system came into being.
+Researchers report their findings today in the journal Nature. 
+The prevailing theory is that Saturn's rings, reflected by the distant Sun, comprise the remnants of an icy moon that long ago was smashed open by an asteroid or comet. 
+But a collision of this kind normally gives rise to debris in a wide range of sizes, from big lumps a kilometre wide to pebbles a few centimetres across. 
+Photographs and radar sensing by scout probes, though, have until now shown Saturn's ring particles to be remarkably small, between a few centimetres to a few metres across. 
+The only big exceptions were a pair of kilometre-wide moons called Pan and Daphnis that lurk within the ring system. There seemed to be nothing in the intermediate size. 
+The missing rocks
+Astronomers led by Dr Matthew Tiscareno of Cornell University, New York, believe they have found some of the missing medium-sized rocks. 
+Their evidence comes from data sent back by the orbiting US spacecraft Cassini, which shows gaps, shaped rather like a propeller blade or an elongated teardrop, in some of the rings. 
+Tiscareno's team deduct that the gaps are caused by what they call embedded moonlets.
+These are rocks about 100 metres across that were too small to be seen in the Cassini pictures but which must have briefly scattered the particles as they orbited, rather like a ship forms a bow wave and trails a wake that then closes  behind it. 
+Four of the teardrop gaps have been spotted so far, and more may emerge later this year when Cassini returns to the ring system to view it from a different angle. 
+The finding is the latest evidence to suggest that Saturn's seven rings, first spotted by Galileo in 1610 according to legend, are a dynamic, continuous evolving structure. 
+The debris becomes clustered, gets torn apart by collision and is then reassembled by Saturn's gravitational forces and the particles' own gravitational attraction. 
+Research presented last year found that the outermost A ring has many empty spaces.
+And part of the innermost D ring has become dimmer and moved closer to Saturn by about 200 kilometres since it was observed by the US probe Voyager in 1980 and 1981.
+
+Much is at stake under the new research funding plan, both for the older established universities and the new ones
+A proposed plan requiring Australian universities to prove their impact on business and the community before they get government research funding has met with a mixed response.
+And curiously, universities that focus on applied research are worried they could lose out under the proposed plan.
+Federal science and education minister, Julie Bishop, this week released a report that recommends an overhaul of the way university research funding is allocated.
+The final advice to government on the Research Quality Framework (RQF) comes after two years of deliberation.
+Under the current "metrics-based" system, the government allocates block funding to universities based on a formula.
+The formula values such things as success in gaining competitive grants, the number of students completing PhDs and the number of publications produced.
+The new system would use expert panels to allocate funds based on a more detailed assessment of research quality, and, for the first time, an assessment of the impact of the research on "end-users of research".
+Go8 response
+The Group of 8 (Go8) universities, welcome the idea of measuring impact but have some concerns.
+"While impact is very important and research should always be done with some outcomes in mind, we shouldn't expect that every bit of research that's being done in our universities is able to predict the sorts of outcomes [it will have]," says Go8 executive director, Virginia Walsh.
+The large "sandstone" universities that make up the Go8 have the largest output of high-profile international research collaboration and publications, and receive the lion's share of research funding under the current system.
+The Go8 says the new plan is modelled on a 20-year old UK system that is about to be disbanded and replaced by a metrics-based system.
+"It's ironic," says Walsh, "that we are looking at the possibility of emulating something that has now been replaced by something much closer to what we've currently got."
+Other universities nervous too
+Outside the Go8 are newer and generally smaller universities that tend to focus more on applied research.
+While you might think a system that values impact might work in their favour, such universities are nervous they could lose out under the new plan to the larger universities.
+Professor Greg Baxter of the New Generation Universities group, for example, says it will depend on how research "impact" is measured and weighted against research "quality".
+"I think the potential for significant disadvantage for universities like us is clearly there because you can set up the rules and the metrics to advantage the Group of 8 should it be so desired," says Baxter who is pro vice-chancellor of research at Victoria University.
+Professor Andris Stelbovics, of the Innovative Research Universities Australia group of universities is also worried about the relative weight that will be given to impact and quality.
+"We do pure basic research or research based purely on scholarship," says Stelbovics, who is pro vice-chancellor of research of Murdoch University. "But we also have quite a few research teams that work in applied areas."
+He says he is concerned about how a university research consultancy with local government to solve waste management problems would be valued under the new system.
+His group also wants funding for agricultural problems such as wheat rust disease, which is only of relevance to a small group of countries including Australia, to be valued equally in terms of impact with research of global significance.
+Timetable questions
+Minister Bishop has set up a new group headed by chief scientist Dr Jim Peacock to advise on the implementation of the new plan once it's finalised and accepted by the government.
+But universities are concerned about the proposed timetable for implementation.
+Walsh thinks it will take at least another year to work out the details of the plan, including a cost-benefit analysis.
+And the universities also want to make sure they are given money to implement the new system so their researchers are researching rather than filling out audit forms.
+"If they were to do it extremely well, it's probably too expensive," says Baxter. "And if they do it on the cheap it may not be any better than the system we've currently got."
+
+Dr Jeffrey Stilwell in the background with PhD student Chris Consoli holding the theropod toe bone fossil they found on the Chatham Islands
+The first proof that land-dwelling dinosaurs lived on remote islands in the South Pacific has been unveiled by an Australian-based researcher.
+Dr Jeffrey Stilwell, a palaeontologist from Melbourne's Monash University, says he discovered the fossilised foot, finger and spinal bones of carnivorous dinosaurs on the Chatham Islands, about 850 kilometres east of New Zealand. 
+The discovery confirms the Chathams were once connected to New Zealand by a finger-like extension, Stilwell says.
+"Prior to our discoveries, only a few isolated examples of dinosaur fossils had been found in the northern part of New Zealand," he says. 
+"Now we've found dinosaur remains almost 1000 kilometres east out in the middle of the South Pacific."
+He adds that his team has already uncovered more dinosaur fossils in the Chathams than had been unearthed in New Zealand over the past 25 years. 
+While some dinosaur remains had been found along the Antarctic peninsula and in South America, this is the first such discovery in the southwest Pacific and is possibly unique in the southern hemisphere, he says. 
+"[The dinosaurs] were on their own evolutionary path for probably 15 million years since the separation of the Chathams-New Zealand region some 85-80 million years ago," he says. 
+Stilwell found the first fossils by accident when he visited the Chatham Islands in 2003. 
+"No one had even hypothesised that there were any fossils out that far," he says. 
+With a grant from the National Geographic Society, Stilwell and associates returned to the archipelago to continue their research, the first findings of which were published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology. 
+But he says a subsequent trip to the islands in February yielded a "huge collection" of new fossils, which are still being analysed. 
+"The story's going to get better," he says.
+
+New guidelines recommend 30 chest compressions to every two breaths to improve blood flow to the heart and brain
+New advice on how best to perform cardiopulmonary resuscitation (CPR) suggests doubling the number of chest compressions, Australian emergency medicine experts say.
+This should mean more sustained blood flow, especially to the heart and brain.
+The move, which was announced recently by the Australian Resuscitation Council, is now in line with international consensus and best evidence, say the experts.
+The new protocol recommends 30 chest compressions to every two breaths when resuscitating infants, children or adults.
+The pattern of two ventilations then 30 compressions should continue, to achieve a rate of 100 compressions a minute, says council chair and University of Western Australia lecturer in emergency medicine, Associate Professor Ian Jacobs.
+He hopes the one conversion rate for all basic life support rescue attempts and patients would be easier to remember and increase the likelihood people will at least try CPR. 
+The new protocol also recommends compressions be delivered faster and harder, people should visualise the centre of the chest and compress there, interruptions should be minimised, a defibrillator attached urgently, other ventilation avoided and says any attempt at resuscitation is better than no attempt.
+Kelli Mitchener from the Australian College of Critical Care Nurses and a nurse at Melbourne's Austin Hospital, says the new ratio means better blood flow.
+"By increasing the number of compressions it means there will be fewer pauses where blood circulation is not occurring, hopefully improving the patient's outcome," she says.
+The changes are based on a review of published evidence which found giving more compressions may help save more lives and a consensus developed by the International Liaison Committee on Resuscitation published in the journals Resuscitation and Circulation.
+"There are 30,000-35,000 cardiac arrests annually in Australia - due to a heart attack, drowning or drug overdose for example - but less than half receive CPR before an ambulance arrives and most [who don't] will die," says Jacobs.
+The guidelines, which are available online, are for the public but include sections for doctors, hospitals and ambulance officers.
+St John Ambulance begins teaching the new techniques in its first aid classes from April.
+
+A new lubricant that forms polymers to protect engine wear also saves oil, according to new research
+A new smart lubricant that forms a protective film when it meets two surfaces rubbing together means engines need less oil, a chemical conference has heard this week.
+Using about 4.5 grams of the lubricant saves more than 450 grams of oil, according to a presentation at the American Chemical Society's meeting this week in Atlanta.
+While its inventors do not believe the lubricant can replace standard motor oil in vehicles, they say it may someday replace the oil used to test engines and mechanical systems. 
+Additives developed from the same technology could also stave off wear, improve engine performance and reduce pollutants, its developers say.
+The technology behind the new compounds is called tribopolymerisation. 
+"By tribopolymerisation, we mean the use of small molecules in a fluid, such as an oil, to reduce wear and damage of the sliding surfaces by forming thin polymer films, which offer protection," says US researcher Professor Michael Furey, from Virginia Tech, who developed the process with Czeslaw Kajdas and colleagues at the Radom Technical University in Poland. 
+"It is a process of molecular design. We do not add any polymers to the system, nor do we coat surfaces with polymers. Instead, our monomers are designed to form thin polymer films directly on the rubbing surfaces continuously and only where needed," Furey says. 
+The international team of scientists has been working on the project since 1981, but recent developments include a precise way of measuring what happens as the films form; the discovery of new classes of compounds, such as the engine lubricant; and agreements with three organisations who hope to further develop and market the technology. 
+Furey says that 16 engines recently were treated with about 4.5 grams of the smart composition. 
+"All passed the run-in tests successfully with no signs of damage," he says. "In a subsequent series of tests in a different factory location, 24 engines were pre-treated the same way. All 24 engines were in perfect condition after the run-in tests. The results were quite amazing." 
+Smelly fumes
+He and his colleagues also say the technology could reduce the "emission of smelly fumes" from the use of diesel in trucks, cars, buses and equipment. 
+Currently, many countries, such as Sweden, and US states, like California, have imposed limits on the sulfur content of diesel fuels, since sulfur oxide is one of the stinkiest pollutants. 
+The catch is that the substitute low-sulfur fuels increase wear and tear on the fuel injector and fuel pump, according to the researchers, who say they have invented diesel fuel "lubricity additives" that work with low-sulfur fuels to reduce their damage on the engine. 
+Dr Jorn Larsen-Basse, former director of the Surface Engineering and Tribology Program at the US National Science Foundation, says the technology is "innovative". 
+"It works well with metal surfaces, especially steel, because molecules stick onto it easily. The engine pretreatment application might very well be possible," Larsen-Basse says.
+The inventors hope to conduct further studies on how high surface temperatures and other engine factors affect the performance of the new compounds.
+
+Power poles damaged by Cyclone Larry, which hit northern Australia last month. But cyclones can be a lot worse, says one expert
+Cyclones like Larry are not as intense as we think, says a cyclone risk engineer.
+And if we don't get our forecasts right, he says Australia could be left unprepared for the worst.
+Dr Bruce Harper, a Queensland-based consultant who has a long association with the Bureau of Meteorology, says Cyclone Larry, which hit the northern town of Innisfail recently, was not as powerful as people think.
+He says while the bureau predicted the cyclone would hit land as a category 5 cyclone, with winds of around 290 kilometres per hour, the closest weather stations showed it was a lot weaker.
+Harper says a station at South Johnstone, 7 kilometres from Innisfail, showed wind speeds of 180 kilometres per hour.
+And the maximum speeds recorded at the nearest offshore station were at Flinders Reef, which measured 240 kilometres per hour.
+Both these measurements fall within the definition of a category 4 cyclone.
+"My estimation is that it was a low category 4," says Harper, who also advises local and state governments on cyclone risk and insurers on estimated losses from cyclones.
+"It wasn't 290 kilometres [per hour] and if it was there would be barely a house standing in parts of Innisfail," he says.
+"The community needs to know that cyclones can be a lot worse than this."
+Inaccuracy not significant
+Gary Foley of the Bureau of Meteorology in Melbourne acknowledges the cyclone was weaker than predicted.
+But, he says when all the data is in, the actual wind speed will probably be calculated to be just 40 or 50 kilometres per hour less than what was predicted.
+"So how does that translate to a person making a response before the storm hits. Do you put in a couple more nails in the roof or something?"
+While Harper acknowledges the bureau helped people prepare for a severe cyclone and is keen to emphasise the agency does the best with the technology and resources it has, he says a difference of 50 kilometres per hour could have a huge impact on damage.
+And he also thinks that even after final estimates are made the bureau will still be overestimating the strength of Larry and he says such overestimates present broader problems.
+Higher and lower estimates
+Harper says most predictions of cyclone intensities can't be accurately verified because there aren't enough weather stations collecting data on how strong the winds really are when they hit land.
+But, he says, cyclone risk engineers like himself use the closest weather station measurements, along with the actual damage caused by cyclones, to make their own estimates of the strengths of cyclones once they hit land.
+This information is used to build models that help develop building authorities to specify standards for cyclone-proof houses.
+And the models help insurance companies work out how much money they need to keep aside for cyclone damage payouts.
+Harper says estimates by cyclone risk engineers are almost always lower than those provided by meteorological predictions.
+And he is concerned that the more widely publicised overestimates from the bureau might lead to public complacency.
+It could give people a false impression of cyclone impacts and downplay the importance of building cyclone-resistant buildings, he says.
+Uncertainties
+Harper says one of the reasons why the bureau is overestimating the strength of cyclones is because there are huge uncertainties in their measurements.
+He says the satellite technology they use to measure cloud temperature as a proxy for wind speed is out-dated.
+It doesn't take into consideration the fact that cyclones can change rapidly or the fact that the size of a cyclone can affect its intensity, he says.
+Harper says the bureau should have more radar to measure actual wind speed, and possibly fly aircraft through cyclones to collect data, as occurs in the US.
+And there should be many more weather stations around the country so predictions can be more easily verified and models adjusted accordingly.
+The bureau's Foley agrees that, given the funds, better technology and more weather stations would give more accurate predictions but doubts it would be worth the cost.
+He appreciates engineers like Harper would like more weather stations but says the bureau can't be expected to be all things to all people and given the uncertainty that exists they would rather err on the side of caution.
+
+The chemical composition of the Sun appears very different to what we assumed, analysis of Moon soil has revealed
+Analysis of the first sample of lunar soil collected by Neil Armstrong has thrown into disarray what researchers believe about the Sun, an international team of scientists says.
+Dr Trevor Ireland from the Australian National University and colleagues report in the journal Nature today the results of a study of oxygen isotopes on the surface of soil grains returned to Earth by the 1969 Apollo 11 mission.
+It was hoped the study would provide clues about the chemical make-up of the Sun and the proto-planetary soup that gave birth to our solar system.
+In particular, researchers hoped to find evidence for either of the two reigning theories about the Sun's composition.
+According to one theory, the Sun has a similar oxygen composition to the planets.
+The other theory suggests it has enriched levels of the isotope oxygen-16.
+Instead, the study indicates that while the Sun is dissimilar to bodies like the Earth and meteorites, it has lower levels of oxygen-16 than expected.
+"This was a completely unexpected result for us," Ireland says. "Our Sun is not the Sun that we thought it was."
+The finding also suggests the Sun somehow ended up with a different composition from the cloud of dust and gas that preceded it, Ireland says.
+He says this is based on other small rocky bodies, known as carbonate chondrites, which are the oldest known things in the solar system and have up to 500 times more oxygen-16 than other oxygen isotopes.
+Solar winds
+Ireland says while we can't get samples directly from the Sun, we can infer its composition by looking at lunar samples, which are believed to reflect its composition.
+This is because lunar soil contains oxygen isotopes "implanted" by solar winds carrying elements blown out from the Sun.
+But after using a caesium beam to erode the surface of the soil grains and measure the isotopes oxygen-16, oxygen-17 and oxygen-18, the researchers discovered unexpectedly low levels of oxygen-16.
+"We found that the oxygen ... did not agree with either a planetary composition or the oxygen-16 rich composition," Ireland says.
+"The oxygen isotopes are telling us that the mix of components in the Sun is different to that in the planets, particularly in regard to the amount of dust versus gas that comprises the Sun versus the planets."
+Ireland says an analysis of oxygen from Jupiter's atmosphere, comets and other bodies in the solar system could shed more light on the mystery.
+
+Vietnam's fight against bird flu
+Humans infected with bird flu appear to have more of the virus in their throat and nose than people with standard human influenza strains, a conference is due to hear today.
+The findings may help explain why avian influenza A (H5N1) has such a high death rate in humans, more than 50% mortality.
+Dr Menno de Jong, head of the virology department at the University of Oxford's clinical research unit at the Hospital for Tropical Diseases in Ho Chi Minh City, studied 17 patients with bird flu.
+He found the virus is often associated with disseminated infection in blood and faeces, and with higher levels of viral replication in the nasopharynx compared with contemporary Vietnamese influenza cases.
+High viral levels, disseminated infection and an intense inflammatory response also seem associated with poor outcomes, he is due to tell the Australasian Society for Infectious Diseases annual scientific meeting in Wellington, New Zealand today. 
+"Our main findings are that influenza H5N1 seems to be characterised by high virus levels in the respiratory tract, evidence suggesting disseminated infection [virus detection in blood and rectum] and [likely as a result of this] an intense inflammatory response," de Jong says.
+High levels of viral replication are likely to play a role in determining a patient's outcome by direct effects of the virus or by the inflammatory response to the virus, he says.
+"The reason for the high mortality probably is not high replication rates per se, but high replication rates of an extremely virulent virus," he says.
+Antiviral drugs should be started early to prevent as much inflammatory response as possible, he says.
+Two of the people in his study developed resistance to the antiviral drug oseltamivir and died, as reported in the New England Journal of Medicine last December.
+Resistance implies suboptimal suppression of replication and strategies to minimise it include ensuring adequate levels of the drug in the body by increasing the dose or giving it intravenously, or combining it with other antiviral drugs, he says.
+De Jong says avian-type cell receptors being mostly in the lower respiratory tract could explain why bird flu does not spread among humans, as reported in the journal Nature recently.
+This may explain why viral load seems higher in the throat than nose, and why all infected developed pneumonia, he says.
+
+Cockroaches make decisions as a group, new research shows
+Cockroaches govern themselves in a very simple democracy where each insect has equal standing and group consultations precede decisions that affect the entire group, indicates a new study. 
+The research determines that cockroach decision-making follows a predictable pattern that could explain group dynamics of other insects and animals, such as ants, spiders, fish and even cows. 
+Cockroaches are silent creatures, save perhaps for the sound of them scurrying over a countertop. They must therefore communicate without vocalising. 
+"Cockroaches use chemical and tactile communication with each other," says Dr Jos&eacute; Halloy, who co-authored the research in the current Proceedings of the National Academy of Sciences. 
+"They can also use vision," says Halloy, a scientist in the Department of Social Ecology at the Free University of Brussels in Belgium.
+"When they encounter each other they recognise if they belong to the same colony thanks to their antennae that are 'nooses', that is, sophisticated olfactory organs that are very sensitive," he says.
+Give me shelter
+Halloy tested cockroach group behaviour by placing the insects in a dish that contained three shelters. The test was to see how the cockroaches would divide themselves into the shelters. 
+After much "consultation", through antenna probing, touching and more, the cockroaches divided themselves up perfectly.
+For example, if 50 insects were placed in a dish with three shelters, each with a capacity for 40 bugs, 25 roaches huddled together in the first shelter, 25 gathered in the second shelter, and the third was left vacant. 
+When the researchers altered this set-up so that it had three shelters with a capacity for more than 50 insects, all the cockroaches moved into the first "house". 
+A delicate balance
+Halloy and his colleagues found that a balance existed between cooperation and competition for resources. 
+"Cockroaches are gregarious insects [that] benefit from living in groups. It increases their reproductive opportunities, [promotes] sharing of resources like shelter or food, prevents desiccation by aggregating more in dry environments, etc," he says.
+"So what we show is that these behavioural models allow them to optimise group size."
+The models are so predictable that they could explain other insect and animal group behaviours, such as how some fish and bugs divide themselves up so neatly into subgroups, and how certain herding animals make simple decisions that do not involve leadership. 
+Important research
+Dr David Sumpter, a University of Oxford zoologist, says the new study "is an excellent paper" and "important". 
+"It looks both at the mechanisms underlying decision-making by animals and how those mechanisms produce a distribution of animals amongst resource sites that optimises their individual fitness," he says.
+"Much previous research has concentrated on either mechanisms or optimality at the expense of the other." 
+For cockroaches, it seems, cooperation comes naturally.
+
+Professor Frederick Short retrieving marked plants from Australia's Great Barrier Reef
+Seagrasses around the world are in decline, according to a global study that says human impact is largely to blame.
+But Australia's 'underwater forests' in Queensland have bucked the trend and are generally in good shape, the researchers find.
+Seagrass beds are shallow water ecosystems, like a forest on the ocean floor.
+Not only do they serve as protective nurseries for juvenile fish and shellfish, and a habitat and feeding ground for many marine species, they protect the coastline from currents and weather-related erosion. 
+Since 2001, the University of New Hampshire's Professor Frederick Short and colleagues have been running the global monitoring program SeagrassNet.
+This has involved monitoring seagrass health at 45 sites in 17 countries worldwide, including Australia.
+In general, the researchers found a decline in seagrass around the world.
+While they have not ruled out globate climate change as a factor, they believe human impact is mainly to blame.
+For example, at a state park in Malaysia researchers discovered that seagrass decline was due to on-shore logging.
+This had increased the level of water-borne sediments, thus decreasing light reaching the bottom where seagrasses grow. 
+When seagrass beds disappear, the impact is major. For example, a disease outbreak in the 1930s wiped out 90% of eelgrass in the North Atlantic.
+As a result, the scallop fishery in the mid-Atlantic disappeared and never really recovered.
+The scientists are also monitoring seagrass beds in Thailand, home to shellfish, to see the effects of the 2004 tsunami.
+Healthy pockets
+Rob Coles, principal scientist with Queensland's Department of Primary Industries and Fisheries, based at the Northern Fisheries Centre, Cairns, led the Australian arm of the research.
+He says the good news is that seagrass beds off Green Island, 25 kilometres east of Cairns, are very healthy.
+And so are seagrasses he and his colleague monitor in 50 sites across Queensland as part of the Seagrass Watch initiative.
+He puts that down to low population density, good light, clean water and comprehensive water management and conservation programs.
+"In fact, there is no real loss of seagrass in the Great Barrier Reef World Heritage Area that we really know about. There have been temporary losses due to storm damage and we've had a big loss in Hervey Bay due to cyclone damage, [and declines in some areas of the Whitsundays], but generally [it's good]," he says.
+"But that's not to say there is no cause for concern because increasingly people are moving to the coast and that will eventually impact on shallow water seagrasses. So we must [remain vigilant]."
+
+All writing systems contain key shapes like T and X that are based on nature, researchers say
+When you pick up a pen and write you're not simply scratching down a set of abstract marks, but representing the trees, mountains and horizons that surrounded your forebears, according to new research.
+The research, which will be published in next month's issue of The American Naturalist, looked at more than 100 writing systems throughout history.
+It concludes that all letters, and symbols like trademarks, share universal shapes and forms based on patterns found in nature.
+"These classes of human visual signs ... possess a similar signature in their configuration ... suggesting that there are underlying principles governing the shapes of human visual signs," the team from the California Institute of Technology writes.
+The researchers say their work provides evidence that we select our visual signs to match the contours of natural scenes.
+This is because we have evolved to be good at visually processing these forms, the researchers say, and the shapes we use in writing are chosen for visual recognition at the cost of manual efficiency.
+In other words, we use the letters we do because they are easy to read, although they mightn't be the most efficient shapes to write.
+This is in contrast to shorthand, where forms are selected for speed and efficiency of writing at the cost of speedy reading.
+L, T or X
+Dr Mia Stephens from the University of South Australia, a lecturer in linguistics, text, language and society, says the researchers reduced written languages to a set of basic shapes, including T, L and X.
+"They've organised and categorised all the different shapes and looked at the frequency and distribution of the shapes and there's a pattern," she says.
+"[They say] you can detect similarities of human writing systems and [the shapes are] topographical, so you can stretch them, and squeeze them and muck around with them but they've still got basically the same number of links and junctions," she says.
+The researchers also provide three sets of natural scenes from tribal, rural and urban surroundings to show how these forms are present in our surroundings.
+But Stephens says the premise of the article is too simplistic.
+She questions the primary evolutionary impulse of looking at scenery and imagines what our forebears would have thought at the time.
+"We have to eat, we have to run away from predators, and we've evolved to do those things, not just look at scenery as scenery."
+Stephens also says the nature of written language is likely to change in future, leaving the theory obsolete.
+"This argument is about the past, and the future of writing is going to be completely different because we've now got keyboards," she says.
+
+Researchers have grown artificial bladders from patients' own cells that seem to work when transplanted into the body. But no-one knows how safe the procedure is in the long term, says one commentator
+Custom-made bladders grown from patients' own cells have been successfully transplanted and work, in some cases for years, scientists report. 
+Writing in The Lancet journal, they describe the cases of seven patients who had new bladders engineered from a plug of tissue grown from their own dysfunctional bladders. 
+"We have shown that regenerative medicine techniques can be used to generate functional bladders that are durable," says Dr Anthony Atala of Wake Forest University in North Carolina, who led the research. 
+"This suggests that regenerative medicine may one day be a solution to the shortage of donor organs ... for those needing transplants." 
+Patients given transplants of bladders made from their own cells would not need to take drugs to prevent organ rejection, as do patients given transplants from either living or dead donors. 
+Atala's team worked with immature cells known as progenitor cells from the patients' bladders.
+The researchers have been working for 16 years to find ways to first identify and separate these cells, then to coax them into growing on a scaffold into the two main cell types found in bladders. 
+The patients were children and teens aged 4 to 19 who had poor bladder function because of a congenital birth defect that causes incomplete closure of the spine. 
+Their bladders are too stiff and can cause pressure on the kidneys that eventually damages them. Such patients often get bladders reconstructed from the intestines, but the procedure is imperfect. 
+Atala, a urinary surgeon and an expert in regenerative and stem cell science, wanted to try to grow replacement bladders for the patients. 
+Measuring for a match
+"We do a three-dimensional CT scan, a computerised imaging analysis, and we figure out what the bladder shape should look like," Atala says.
+"We then take a small biopsy of their bladder, about half the size of a postage stamp." 
+The researchers then separate the muscle cells on the outside of the bladder, and the specialised cells that line the bag-like organ. 
+Then they create an artificial scaffold on which to layer the cells. The cells are grown in special compounds that nurture the progenitor cells and allow unwanted cells to die out. 
+The resulting cells are then layered onto the scaffold and incubated until they grow and spread. 
+"It is very much like baking a layer cake," Atala says. "You are placing these cells on one layer at a time." 
+Atala works with stem cells, the body's master cells, but in this case, his team made use of progenitor cells, which are slightly further along the pathway from a 'blank slate' master cell. 
+Organ factory
+His team is also working to create blood vessels, kidneys, pancreases, hearts, livers and nerves. 
+The technology has been licensed from Atala's former employer, the Children's Hospital in Boston, to a new company called Tengion created to take advantage of Atala's work. 
+The new bladder technology has not yet been approved by the US Food and Drug Administration for widespread use.
+In a commentary, Dr Steve Chung, from the Advanced Urology Institute of Illinois, describes the work as a "milestone" that could especially help people  with cancer of the bladder, which is overwhelmingly caused by smoking. 
+But he recommends putting the celebrations on hold until the technique has been tested by other teams, and over longer periods, to see whether it is safe as well as effective.
+
+Are your hormone levels going up?
+Just anticipating a good laugh is enough to increase the level of feelgood hormones in your blood, a conference has heard.
+Previous work has shown that laughter triggers a cascade of beneficial physiological changes.
+But researchers presenting a new study at the Experimental Biology 2006 conference in the US recently say they've now shown that merely anticipating "mirthful laughter" before watching a funny video has significant neuroendocrine effects. 
+Professor Lee Berk of Loma Linda University in California says people who were just about to watch their favourite funny video had 27% more beta endorphins and 87% more human growth hormone (HGH) than those who were told they'd be reading magazines for an hour.
+"We believe that results suggest that the anticipation of a ... laughter ... event initiates changes in neuroendocrine response prior to the onset of the event itself," he says.
+Beta endorphins provide natural pain relief and low levels are associated with depression.
+HGH is involved in growth, development and cell maintenance and some research suggests it plays a role in maintaining a healthy immune system.
+Gags or mags?
+Berk describes these effects as "the biology of hope", and says they are linked to the anticipation of a positive mood state.
+In the study 16 people where asked to choose their favourite funny video. 
+They were told three days before the experiment whether they would get to watch their video or sit in a "neutral room" and thumb through a pile of magazines.
+Their blood hormone levels were tested just before the video was turned on, four times during an hour of video watching or magazine reading and three times afterwards.
+Berk says the hormone levels stayed high throughout the video and afterwards.
+Anticipation can be powerful
+Professor Nicholas Keks of Monash University, an Australian researcher whose expertise includes hormones in psychiatry, says anticipation is a powerful emotion in terms of triggering physiological and emotional responses.
+"Anticipation is a huge issue in areas that affect our psychology, whether it be anticipation of pleasurable activities or a bit of pain," he says.
+"You just have to look at the classic example of salivation before food, or expectation of sexual activity ... I think laughter belongs in that group."
+He says the physiological changes shown in the study are probably linked to the so-called "flight or fight" response of nervous system arousal.
+"Part of laughter is a general arousal and what that will do is stimulate various hormonal and autonomic systems which go along with arousal," he says.
+Berk says he next wants to study cytokine and inflammatory immune responses to the anticipation of laughter.
+
+Astronomers found the methanol cloud in the W3(OH) region of the Milky Way, where stars form
+Astronomers say they have spotted a cloud of alcohol in space that measures 463 billion kilometres across, a finding that could shed light on how giant stars are formed from primordial gas.
+The vast bridge-shaped cloud of methanol has been spotted in a region of the Milky Way called W3(OH), where stars form by the gravitational collapse of concentrations of gas and dust. 
+Researchers led by Dr Lisa Harvey-Smith spotted the cloud from the UK's Jodrell Bank Observatory.
+They present their findings today at a meeting of the UK's Royal Astronomical Society in Leicester. 
+The researchers have revealed giant filaments of gas by detecting masers.
+These are like lasers. But rather than emitting beams of light, masers emit beams of microwave radiation, which the molecules in the gas cloud amplify millions of times.
+The largest of the maser filaments, which were detected using the Merlin radio telescope, was 463 billion kilometres long.
+The researchers say the entire gas cloud seems to be rotating as a disc around a central star, just like accretion discs in which planets form around young stars.
+Harvey-Smith says the discovery is surprising as until now researchers had thought of masers as point-like objects or very small bright hotspots surrounded by fainter halos.
+In 2004, astronomers spotted methanol for the first time in one of the disc-like clusters that form around nascent stars. 
+That discovery opened up a new area of debate in astrophysics, challenging the conventional view that interstellar chemistry could not provide the conditions for creating complex molecules.
+Until then researchers thought the molecules would be ripped apart by ultraviolet radiation from stars and other tough conditions. 
+Around 130 organic molecules have also been identified so far in space, fuelling speculation that these complex molecules may have helped to sow the seeds for life on the fledgling Earth.
+
+The 2004 Boxing Day tsunami destroyed the forest that once grew along this Indian coastline
+Mangroves and coastal forests offer little or no protection against tsunamis, says new research that debunks earlier findings.
+Last year researchers studied 17 coastal villages in the Tamil Nadu region of India in the months after the 2004 Boxing Day tsunami.
+They concluded that death rates were lower in villages fronted by mangroves.
+But when researchers including those from the Australian Research Council's Centre of Excellence for Coral Reef Studies analysed the data they found a very different story.
+"The most important determinants of the number of people that died [in the Tamil Nadu region] were the distance of the village from the coast and its height above sea level," says co-author and Australian marine ecologist Dr Andrew Baird.
+"In effect, there was no protective function of these coastal forests."
+Baird says while the hypothesis of the original research was reasonable, it was not borne out by their findings, published in the April issue of the journal Estuarine and Coastal Shelf Science.
+Their analysis revealed that the distance of a village from the coast and the height of the village above sea level explained 87% of the variation in mortality among villages.
+Once these two variables were taken into account, vegetation area seemed to account for less than 1% of the variation.
+"Mangroves and intact coastal ecosystems are wonderful and necessary things ... but they won't protect you from tsunamis," Baird says.
+"We're concerned that by telling people that mangroves and coastal forest will protect them from a tsunami will give [people] a false sense of security.
+"When the next wave comes people may be misled into thinking that they are safe because their village is fronted by a mangrove forest.
+"The other concern is that the concept of 'green belts' and buffer zones is being used as an excuse by the tourism industry and other interests such as plantation owners to move people away from their homes and livelihoods and take this land from them."
+Baird says people would be better to concentrate on early-warning systems and effective evaluation strategies in the event of another tsunami.
+"That's the way you're going to save lives," he says.
+Researchers from the University of Guam and the Wildlife Conservation Society-Indonesia Program were also involved in the new analysis.
+
+Will the Venus Express mission yield new insights into what awaits Earth?
+A space probe that arrives at Venus today will yield new insights into what caused the runaway greenhouse effect there and could bring a salutary warning for our own planet, scientists say.
+The European Space Agency's Venus Express will spend three years peering through a shroud of toxic sulfur clouds to glean information about the climate, atmosphere and curious 'backwards' rotation of the so-called pressure cooker planet.
+It's also hoped the mission will help answer questions about what caused its mysterious 'resurfacing' some 500 million years ago and whether it is being shaken by seismic activity and volcanoes.
+It may also provide clues about whether the Earth and Venus were once similar, and when and why they took such radically different paths, says Dr Frank Mills of the Australian National University, an expert in the chemistry of the Venusian atmosphere who has been working with scientists directly involved in the mission.
+"There are many uncertainties in trying to reconstruct Venus' evolution," he says.
+"Some of these may be resolvable by making appropriate observations."
+The greenhouse effect
+The UK's Royal Astronomical Society says "any astronaut unlucky enough to land [on Venus] would be simultaneously crushed, roasted, choked and dissolved".
+Venus' atmosphere is 90 times denser than Earth's and 96% is made up of the greenhouse gas CO2.
+Scientists say this causes a strong warming effect and heats the surface of the planet to around 500&deg;C.
+There are no signs of water on Venus and its surface is apparently more arid that the driest desert on Earth.
+Associate director of the Australian Centre for Astrobiology at Macquarie University Dr Jeremy Bailey says isotope ratios in the atmosphere suggest that Venus once had oceans that have since evaporated.
+Dr John Lattanzio, from Australia's Centre for Stellar and Planetary Astrophysics at Monash University, says that unlike Earth, Venus lacks a CO2 cycle.
+On Earth, this cycle means the CO2 gets locked into water and rock and comes back out through volcanic activity, he says.
+"So at any given time [on Earth] there's a lot of CO2 that's out of the atmosphere ... and it self-regulates," he says.
+"Venus doesn't have a CO2 cycle because there aren't any oceans."
+Mills says the probe may also help explain whether the CO2 on Venus is produced by a catalytic reaction.
+He says the probe will also shed more light on the general processes by which atmospheric "greenhouses" work.
+"Venus' atmospheric greenhouse has both similarities to and differences from Earth's," he says, and data from this mission will allow scientists to compare the two.
+A mirror to our own future?
+Bailey says learning more about Venus will help us understand where our own planet is headed.
+But he doesn't believe "anything like Venus will result from the amount of CO2 we're currently putting into the atmosphere".
+Rather, the Earth may end up like Venus over billions of years because of the increasing brightness of the Sun.
+"In about a million years it will have increased by about 10% and it's estimated that will be enough to trigger the sorts of changes that have happened in Venus," he says.
+Mills says that Venus teaches us not to take for granted that the climate on Earth will always be benign and support life.
+"Research on how Venus may have evolved, what its carbon cycle is like and how volcanic activity may influence climate helps in understanding what is possible for a planet," he says.
+NASA's Deep Space Network, including the Canberra Deep Space Communication Complex, has been tracking Venus Express.
+Venus Express is due to end its 400 million kilometre, five month journey around 5.30 pm AEST (07:30 UTC) today.
+For more information including updates and podcasts go to the ESA Venus Express website.
+
+Unique conditions at the Sea of Galilee, or Lake Kinneret as it's also known, may have caused a patch of ice to form near its western shore, says an oceanographer
+The New Testament says that Jesus walked on water, but a US professor says there could be a less miraculous explanation - he walked on a floating piece of ice.
+Professor Doron Nof, a professor of oceanography at Florida State University, says his study found an unusual combination of water and atmospheric conditions could have led to ice formation on the Sea of Galilee.
+He and his co-authors describe the local freezing phenomenon as "springs ice".
+Nof used palaeoceanographic records of the Mediterranean Sea's surface temperatures and statistical models to examine the dynamics of the Sea of Galilee, which Israelis know now as Lake Kinneret. 
+The study, published in the April issue of the Journal of Paleolimnology, found that a period of cooler temperatures in the area between 1500 and 2600 years ago could have included the decades in which Jesus lived.
+A drop in temperature below freezing could have caused ice thick enough to support a human form on the surface of the freshwater lake near the western shore, Nof says.
+This is an area where the researchers say many archaeological findings relating to Jesus have been found.
+It might have been nearly impossible for distant observers to see a piece of floating ice surrounded by water. 
+Nof says he offers his study as a "possible explanation" for Jesus' walk on water.
+"If you ask me if I believe someone walked on water, no, I don't," Nof says.
+"Maybe somebody walked on the ice, I don't know. I believe that something natural was there that explains it.
+"We leave to others the question of whether or not our research explains the biblical account." 
+Nof says the chance of similar icy conditions in northern Israel today is "effectively zero, or about once in more than 10,000 years".
+When Nof offered his theory 14 years ago that wind and sea conditions could explain the parting of the Red Sea, Nof says he received some hate mail, even though he noted that the idea could support the biblical description of the event. 
+And as his theory of Jesus' walk on ice began to circulate, he had more hate mail in his email inbox. 
+"They asked me if I'm going to try next to explain the resurrection," he says.
+
+If you catch bird flu then shop at your local market, the stallholder might need antiviral drugs as well as you
+Giving antiviral drugs both as treatment to infected people and as prophylaxis to their close contacts provides the best chance of minimising the impact of a bird flu pandemic, new research suggests.
+The Australian study found targeted prophylaxis would delay the onset of a pandemic, buying time to hopefully develop and distribute a vaccine.
+But a treatment-based strategy would not significantly delay the onset of the disease or reduce the attack rate, the federal government-funded study found.
+The study, by Dr James McCaw and Dr Jodie McVernon from the University of Melbourne, may be considered by health authorities if avian influenza A (H5N1) reaches Australia.
+McCaw, a theoretical physicist, and McVernon, a paediatrician and research fellow, used a mathematical model to determine the optimal use of Australia's stockpile of 4 million doses of antiviral drugs during a pandemic.
+The model examines differences between using antivirals as treatment once a person has bird flu to reduce their chance of dying and of transmission, and using drugs as post-exposure prophylaxis for those who have come into contact with an infectious person.
+"The model says every time a new person becomes ill, 20 contacts need to be tracked down and given antivirals," McCaw told the Australasian Society of Infectious Diseases annual scientific meeting in New Zealand this week.
+"Research indicates that on average the typical person will have 20 close contacts with people over a few days, 85% being relatives, friends and work colleagues and 15% being others such as shopkeepers and the bus driver."
+The researchers defined a close contact as someone who had a two-way conversation within a metre of an infected person.
+Mild or catastrophic?
+Authorities won't know whether a pandemic will be mild or catastrophic until it hits, McCaw says.
+The model indicates that if mild, treatment of those infected will reduce the number of people who become ill and slow transmission, and prophylaxis will delay the pandemic by several months, buying time to develop a vaccine.
+"For a severe pandemic, the model shows that treatment fails to reduce the overall number of people becoming sick. It has benefits on an individual level by presumably reducing an individual's mortality but not at a population level," McCaw says.
+"But prophylaxis continues to work by delaying exposure."
+The federal Department of Health and Ageing and the National Health and Medical Research Council have contributed to this research as part of pandemic preparedness planning.
+
+Many chickens have been culled to stop the spread of bird flu but experts say the next human flu pandemic is just as likely to come from elsewhere
+Birds are not the only source of viruses that could become the next flu pandemic, say two Australian virus experts, who argue the 1918 Spanish flu virus came from mammals, not birds, as recently suggested.
+And the researchers call for greater surveillance of flu viruses already in people or in other mammals such as pigs or cats.
+Dr Mark Gibbs of the Australian National University and retired virologist Professor Adrian Gibbs report their argument today in the journal Nature.
+"There's a huge focus on birds and that is good but we need to extend the surveillance," says Mark Gibbs.
+In October last year, a team led by Dr Jeffrey Taubenberger of the Armed Forces Institute of Pathology in the US, reported in Nature that the Spanish flu virus, which killed millions around the world in 1918-1919, was a bird virus that leapt the species barrier into humans.
+The researchers said RNA material from the 1918 virus, obtained from preserved tissue of victims of the pandemic, showed it was similar to bird viruses, including the deadly H5N1 strain, that is of such concern today.
+Taubenberger and team also said their argument was supported by family trees constructed by comparing particular 1918 virus genes with equivalent genes from a broad range of viruses that have been found in other animals.
+But Gibbs disagrees with Taubenberger's interpretation of his own virus family trees.
+He says while it is true that the 1918 H1N1 strain originated in birds in the distant past, the question is when?
+Recombination in mammals?
+Taubenberger argues the 1918 virus came directly from birds without combining with viruses in other animals first.
+But Gibbs says the family trees show the 1918 virus evolved from a virus that had already been in mammals for some time.
+He says the fact that you get a different family tree depending on the virus gene used to construct it supports the idea that the 1918 virus was a result of virus recombination in animals like pigs, horses or cats.
+Gibbs also says the virus may have been in humans 50 or 60 years before the pandemic, as suggested by studies showing some elderly people had immunity to the 1918 flu. 
+He suspects it is a coincidence that the 1918 and bird flu viruses Taubenberger studied were so similar, citing a phenomenon known as parallel evolution.
+"Wings have evolved in insects, birds, mammals and reptiles," he says. "But they haven't evolved from a common ancestor with wings. They've evolved wings independently.
+"This happens in flu as well. In fact it's probably very common in flu but not well understood."
+Focus on birds
+Gibbs says Taubenberger's linking of bird flu and the 1918 pandemic increased alarm about bird flu.
+"[But] the notion that the threat from influenzas only comes from birds is actually quite wrong," he says.
+"There is a reasonable chance that the next pandemic may come from an influenza virus which is already in people or in pigs or in some other mammal," he says.
+Gibbs says it is important to know what really happened in the 1918 pandemic because it was one of the most serious disease outbreaks in history.
+
+This fishy creature, which was up to 3 metres long, walked on land with fins that have arm-like bones
+Fossils of a 375 million year old species of ancient fish fill an evolutionary gap in the transition between water and land animals, scientists say. 
+Remains of the new species named Tiktaalik roseae were found encased in frozen rock north of the Arctic Circle.
+It has the fins and scales of a fish but its crocodile-like skull, neck and ribs resemble those of a land animal. 
+"It is a fish that shows a surprising combination of characteristics of land-living animals," says Professor Neil Shubin, of the University of Chicago who's team publishes its discovery in today's issue of the journal Nature.
+"This animal represents the transition from water to land - the part that includes ourselves," he says.
+The nearly complete and very well-preserved specimens show the creature had sharp teeth, a jaw from 25 to 51 centimetres across and a flattened body that could reach 3 metres in length. 
+"It shows us the stages by which land-living animals were constructed," Shubin says.
+Blizzards and bears
+The scientists battled freezing temperatures and blustery storms to get to the site on the remote Ellesmere Island more than 966 kilometres north of the Arctic Circle in Canada.
+They also faced the threat of polar bears during their search for so-called elpistostegid fish, which are thought to be most closely related to tetrapods, land animals with limbs such as amphibians, reptiles, birds and humans. 
+"Previous fossils representing this evolutionary event have really been fish with a few land characteristics, or land vertebrates with a few residual fish characteristics," says Dr Andrew Milner, of the Natural History Museum in London.
+"These fossils show an animal that sits bang in the middle between the fish and land animals." 
+What is generating the most excitement are joints in the fish's pectoral fins, which have bones that compare to the upper arm, forearm and primitive parts of the hand of land-living animals.
+"Most of the major joints of the fin are functional in this fish," says Shubin.
+"The shoulder, elbow and even parts of the wrist are already there and working in ways similar to the earliest land-living animals." 
+The fossils also indicate that the transition from water to land occurred gradually in fish living in shallow water. They gradually developed features to live on land over time. 
+Once was balmy
+The sediment in which Tiktaalik was found has been dated to around 375 million years ago, in the swampy primeval era known as the Devonian. 
+At that time, what is now frigid Arctic Canada had a balmy, sub-tropical climate, for it was part of a mega-continent that straddled the equator. 
+Shubin believes that Tiktaalik's size and shape indicates that it was fitted for living in small streams in a delta system, an environment that probably encouraged the fish to venture into shallow water or even make forays onto land in search of food or shelter from predators. 
+"The skeleton of Tiktaalik indicates that it could support its body under the force of gravity, whether in very shallow water or on land," says co-author Professor Farish Jenkins of Harvard University. 
+"This represents a critical early phase in the evolution of all limbed animals, including humans - albeit a very ancient step." 
+In a commentary in Nature, evolutionary biologists Professor Per Erik Ahlberg of Sweden's Uppsala University and Dr Jennifer Clack of the University of Cambridge hail the find as being quite literally ground-breaking.
+The newly-discovered species owes its name to the Elders Council of Nunavut, which was invited by the scientists to propose a formal name. 
+Tiktaalik, pronounced tic-TA-lick, is the word in the Inuktikuk language for "a large, shallow-water fish".
+
+The test drug triggered a powerful immune response, leaving six trial participants seriously ill. But experts are still puzzled about what exactly happened and why animal studies gave no clue to this possible side-effect
+An investigation into a UK drug trial that left six men seriously ill has found no evidence to suggest there was anything wrong with the drug or the way the tests were run, a regulatory body says.
+In an interim report, the Medicines Healthcare Products Regulatory Agency says the problem appears to be due to an unprecedented biological reaction to the drug in humans that had not been seen previously in animal tests.
+"Our main conclusion is that there was a powerful pharmacological action of this drug in man which was not detectable in the pre-clinical studies done in the non-human primate species, even in far higher doses," says the agency's chief executive Professor Kent Woods. 
+The drug had previously been tested on rabbits and monkeys. 
+As a consequence, the agency will not authorise any trials for similar drugs without taking external, expert advice. 
+"This does not mean a standstill on such research but we feel that we need additional expert advice in certain areas relating to the authorisation of those studies," Woods says.
+UK health secretary Patricia Hewitt also agreed to set up a group of international experts to examine the issue further. 
+Trial by trial
+Six men were left seriously ill at a hospital in north London on 13 March after taking part in the clinical study to test the drug TGN 1412, designed to treat chronic inflammatory conditions and leukaemia. 
+Of the six, five have left hospital and one is making a good recovery. In the days after the trial, two of the men were described as critically ill with organ failure. 
+The trial was run by US drug research company Parexel International Corp on behalf of German company TeGenero AG. 
+At the time, Parexel said it had operated within regulatory guidelines and TeGenero said the response did not reflect the results obtained from initial laboratory studies.
+Monoclonal antibodies 
+TGN 1412 belongs to a class of drugs known as monoclonal antibodies, which specifically bind to target molecules. TGN 1412 targets and activates an immune system protein called CD28. 
+"This is a complex scientific issue which raises important scientific and medical questions about the potential risks associated with this type of drug and how to make the transition from pre-clinical testing to trials in humans," the report says. 
+The regulatory agency will now seek expert, external advice for any future phase one trials, when drugs are first tested on humans, involving monoclonal antibodies or other novel molecules targeting the immune system. 
+Woods says it is vital that they learn lessons from the trial, which he describes as a "wholly exceptional occurrence". 
+David Webb, professor of clinical pharmacology at the University of Edinburgh, says the report's findings could result in a change to the design of first phase trials for monoclonal antibodies. 
+"One obvious difference might be to dose subjects sequentially rather than at the same time, which at the very least would minimise the number of subjects put at risk," he says.
+
+A new form of silicon is said to be easier and cheaper to make than traditional silicon, yet works just as well. But will it be good enough for future generations of computer chips?
+Japanese researchers have made a liquid form of silicon they say might one day be sprayed onto chips with an inkjet printer.
+A team led by Masahiro Furusawa of Japan's Seiko Epson Corporation, says the new form of silicon is easier and cheaper to make than conventional silicon, yet works just as well.
+The researchers report their work today in the journal Nature. 
+The new form of silicon comprises cyclopentasiline, a silicon-based polymer that comprises five silicon atoms joined in a ring and is liquid at room temperature. 
+Ultraviolet light is used to break open the bonds of some of the rings and let the molecules reform into long, placid chains that behave like viscous oil. 
+The mixture is then diluted with a solvent like toluene, and is so fluid that it can be coated onto a surface by spinning, or even sprayed by an inkjet printer. 
+The resultant liquid film is then baked at around 500&deg;C to turn it into a hard mosaic of flat silicon crystals whose semiconductor qualities are as good as the ultrapure slabs made by conventional refining, the researchers say.
+In a review of the work in Nature, Associate Professor Lisa Rosenberg, a Canadian chemist at the University of Victoria in British Columbia, says the new  process has some drawbacks, as it still has to rigorously exclude air and water.
+But she says the ability to make silicon film by inkjet is a clear breakthrough. 
+"[It] will not provide the resolution necessary to pattern a high-density integrated circuit and therefore make a computer chip," she says. 
+"But what it will certainly allow is the remarkably straightforward generation of simple, cheap and flexible circuits for displays, as well as a range of other applications - solar cells, x-ray detections and multi-analyte chemical sensor included."
+Has silicon had its chips?
+Analysts have long predicted the demise of silicon as a chip component due to the costs of purifying and processing it.
+This usually entails taking highly purified natural silicon, which occurs in the mineral silica, and heating it in a vacuum to create a mist of free silicon atoms that then condenses onto a surface. 
+This refining requires conditions to be ultra-clean, as an intruding speck of dust or thimbleful of unwanted gas molecules can ruin the outcome.
+The complexity and cost have led to research into alternatives to silicon.
+The Japanese team's method doesn't need high vacuums, high temperatures or ultra-clean environments.
+
+It's possible to create order by introducing disorder, say researchers who have been working with computer models of swinging pendulums
+Physicists have surprised their colleagues by turning chaos into order.
+US physicists report how a network of interconnected pendulums can be made to swing in sync by being pushed at random times.
+Sebastian Brandt and team at the Washington University in St Louis report their findings in the journal Physical Review Letters.
+The researchers constructed a computer model of an interconnected network of pendulums that swing out of sync when they are pushed at the same time.
+But when the pendulums are pushed at random, they swing in an ordered and synchronised way, the researchers report.
+"The thing that is counterintuitive is that when you introduce disorder into the system - when the [forces on the pendulums] act at random - the chaos that was present before disappears and there is order," says Brandt.
+The researchers say there is much to learn about the role of disorder in complex systems and suggest their work might be relevant to understanding synchronisation of neural activity in the central nervous system.
+Their model system and neurones are both nonlinear, which means that there is no linear relationship between the amount of force applied and the response.
+"When you hear your favourite music twice as loud you don't double the pleasure," says Brandt, explaining how one aspect of the brain, hearing, is nonlinear.
+"This is of course basic research," he says. "But what you can learn from this is that complex systems ... sometimes behave in a very unexpected way, completely opposite to your intuition or expectation."
+Surprising
+Australian physicist Professor Joe Wolfe of the University of New South Wales says the findings are a surprise although not "counterintuitive".
+"It's not really counterintuitive because one's intuition doesn't really work for such systems because they're complicated," he says. "Our intuition is good for dealing with simple things rather than complicated things."
+Wolfe also says the research only has limited applications because the researchers used calculations with specific numbers rather than solving equations made up of symbols such as x and y.
+This means they do not have a solution that can be used to understand every possible case, he says.
+Inspiring a new theory?
+Wolfe says ideally the findings would inspire someone to come up with a general theory to understand what was going on, but he says it is very hard to find mathematical solutions to complicated nonlinear systems.
+And he thinks the idea that the research could help understand neurones is "drawing a long bow".
+"A system of neurones is also a system of nonlinear things that interact in a way that you don't understand and produce sometimes surprising results," says Wolfe.
+"I wouldn't say it's terribly relevant. It's just an interesting observation."
+
+Penguins 60 million years old are closely related to today's yellow-eyed penguin, new DNA analysis suggests
+New analysis of the world's oldest fossil penguins confirms some birds survived the mass extinction that killed the dinosaurs 65 million years ago, researchers say.
+The penguins once lived in shallow seas off New Zealand's east coast 60 million years ago.
+Now a molecular study, published in the journal Molecular Biology and Evolution, links them closely to modern penguins.
+Co-author Associate Professor Ewan Fordyce from the University of Otago says penguins are specialised birds that evolved much later than other species.
+"The fact that they have been found within a few million years of the dinosaurs' extinction is compelling evidence that modern birds must have evolved earlier and diversified during the time of the dinosaurs," he says.
+"It also suggests that many of those bird lineages survived the catastrophe that wiped out the dinosaurs, so it's unlikely that there was a big turnover, with modern birds only emerging after the mass extinction."  
+The study incorporates genetic evidence of the evolutionary relationships between penguins' distant cousins like shearwaters, albatrosses, ducks and moas.
+The researchers used DNA from these birds to provide a broad framework of family relationships which, together with the fossil evidence, is used to predict when those birds must have arisen.
+"We're really confident we have ancient birds and really confident about the date," says Fordyce.
+"It's enabled us to establish an earlier timeframe for when groups of modern birds branched out."
+Most of the New Zealand fossils, officially recognised as the Waimanu penguin genus, were discovered by amateur palaeontologist Al Mannering in the Waipara region just north of Christchurch.
+Some 60 million years ago New Zealand had already separate from Australia and Antarctica and was a low-lying land mass much closer to the South Pole. 
+Waimanu manneringi would have developed in a polar habitat similar to today's yellow-eyed penguin, which it closely resembles.
+Its long bill and condensed wing bones indicate that it would be quite at home eating and swimming in today's Antarctica, the researchers say.
+
+Ant from the genus Ectatomma foraging at the Project Amazonas field station in Peru
+Ants evolved far earlier than previously believed, as far back as 140 million to 168 million years ago, US researchers report.
+And these insects have plants to thank for their diversity, the Harvard University team reports today in the journal Science. 
+The researchers used a genetic clock to reconstruct the history of ants and found the ant family first arose more than 40 million years earlier than previously thought.
+But ants did not diversify into different genera and species until flowering plants came onto the scene, the researchers conclude.
+The study sheds light on one of the most important and numerous animals, which includes hundreds of different species. 
+"We estimate that ant diversification took off approximately 100 million years ago, along with the rise of flowering plants, the angiosperms," says team leader Professor Naomi Pierce.
+"These plants provided ants with new habitats both in the forest canopy and in the more complex leaf litter on the forest floor, and the herbivorous insects that evolved alongside flowering plants provided food for ants." 
+The researchers reconstructed the ant family tree using DNA sequencing of six genes from 139 ant genera, encompassing 19 of 20 ant subfamilies around the world. 
+Such molecular clocks are widely used, alongside fossil and other evidence, to determine how old species are. They work on the basis that DNA mutates at a steady and calculable rate. 
+The researchers found that the poorly known ant subfamily Leptanillinae is the most ancient, followed by two broad groups known as the poneroids, or predatory hunting ants, and the formicoids, the more familiar species such as pavement ants and carpenter ants.
+
+The outer rings of Saturn (top) and Uranus (bottom), in which each system has been scaled to a common planetary radius
+The newly discovered outer ring of Uranus is bright blue, for the same reason the Earth's sky is blue, astronomers say.
+It's made up of tiny particles.
+The ring is "strikingly similar" to Saturn's outer ring, which astronomers last month confirmed was probably generated by one of the planet's moons, Enceladus.
+Like Saturn's ring, the Uranus ring also has a small moon in it, called Mab. But Mab is too small and too cold to be spewing a geyser of ice that contributes to the ring as Enceladus is now believed to be doing. 
+"The outer ring of Saturn is blue and has Enceladus right smack at its brightest spot, and Uranus is strikingly similar, with its blue ring right on top of Mab's orbit," says Imke de Pater, a professor of astronomy at the University of California Berkeley, who helped lead the study. 
+"I think there is no chance that the blue ring is caused by geyser activity," adds de Pater, whose report is published today in the journal Science. 
+"We don't know what the composition of the particles is." 
+Mab is probably covered with water ice, like the other moons of Uranus, but that has nothing to do with the ring's colour, says de Pater. 
+"They are blue because they are tiny particles," she says.
+"That is same reason why the sky is blue. You have little particles that scatter light as blue light." 
+Most other rings around planets in the solar system are red, because of the size of their particles. 
+This is why astronomers missed Uranus's outer ring for so long; scientists were looking for it in the infrared light spectrum.
+Throwing up debris
+The scientists believe that meteoroids hitting Mab's surface throw up debris. The larger pieces remain in the moon's orbit and eventually are swept up, but smaller ones drift around more and eventually make up the ring. 
+The blue ring was only seen after researchers compared notes from near-infrared observations by the Keck Telescope in Hawaii and visible-light photos taken by the orbiting Hubble Space Telescope. 
+Now they are looking for rings around other planets, including Mars.
+Rings are always easier to see when they are edge-on, de Pater says.
+"The interesting thing with Uranus is that in 2007 the rings will appear edge-on," she says. "In 2007 the rings will be 100 times brighter." 
+Saturn's rings
+A second paper, published in Geophysical Research Letters, shows that Saturn's prominent A ring contains more debris than once thought. 
+The Cassini-Huygens spacecraft now orbiting the planet has sent back ultraviolet images that show the ring is 35 times thicker than originally thought. 
+A team at the University of Colorado at Boulder says the particles making up the ring range in size from dust grains to chunks as big as buses, and orbit in long stringy clumps. 
+The same spacecraft helped planetary scientists discover the geyser on Enceladus, leading to speculation that the moon has a liquid water source under its frozen surface.
+
+A new study shows we can only tolerate freeloaders for a short time. After that societies prefer to punish them
+The idea of a happy, cooperative society in which no one gets punished falls apart as soon as a few freeloaders show up, a new study shows.
+Although most volunteers in the study first chose to join a group that did not use punishment, most eventually left for a group that fined transgressors.
+Researchers from the University of Erfurt in Germany and the London School of Economics report their findings today in the journal Science.
+The study can help us understand how to make society work more smoothly and can help in designing policies aimed at ensuring cooperation, writes Assistant Professor Joseph Henrich, a US anthropologist at Emory University in Georgia, in a commentary.
+"Even if nearly everyone is initially cooperative and contributes, free-riders can profit and proliferate, leading to the eventual collapse of cooperation," he writes.
+For example, if most people in society are brave or conserve petrol, he explains, others benefit by evading military service or driving petrol-guzzling cars.
+Playing games
+In the study, researchers asked 84 students to join one of two groups to play a game with tokens. One group of players punished members who did not share freely, while the other group did not. 
+The students could choose which group to join. 
+"Each player is endowed with 20 money [tokens] and may contribute between 0 and 20 [tokens] to a public good," the researchers write.
+"Each group member equally profits from the public good, independent of his or her own contribution." 
+In the punishment group, members could choose to fine other members three tokens, but it cost them one of their own tokens to do so. 
+Two-thirds of the students initially chose the group in which members could not punish others, but many abandoned that group when they saw those in the punishment group were prospering more. 
+And former freeloaders were some of the most enthusiastic converts to the punishment mode, the researchers found. 
+"You can't explain this dramatic change in behaviour by saying that people are just looking for the best pay-off. People gave up pay-off to follow the cooperative norm," says Erfurt researcher Dr Bettina Rockenbach. 
+Punishing the freeloaders
+Dr Bernd Irlenbusch of the London School of Economics adds he was surprised with the extent of punishment.
+"I was surprised so many of the freeloaders exerted punishment on others when they entered the sanctioning institution," he says. 
+When the game ended after 30 rounds, the people in the punishment group had donated an average 18 tokens per round.
+Meanwhile the live-and-let-live group had almost no members and those who remained donated three tokens to the public good on average per round. 
+Little actual punishment was applied during the later rounds of the game, apparently because the threat of punishment was enough to ensure cooperation, the researchers say.
+
+A female Australian redback spider eating a male spider
+Australian redback spiders sniff out how much competition they have for females as they're growing up, and tailor their adult size accordingly, say Canadian researchers.
+Michael Kasumovic and Dr Maydianne Andrade of the University of Toronto report their findings in the latest issue of the journal Current Biology.
+"Males are really tracking the selection pressures that they're facing in an environment. They're aware of male density and the amount of competition they're going to be facing," says Kasumovic.
+Like most spiders, male redback spiders are much smaller than the females but they vary in size.
+Kasumovic and Andrade have found that an individual spider's development is determined by a trade-off between traits that benefit a spider's sexual success versus their longer term survival.
+"A trait that's good for sex is often not good for surviving and a trait that's very good for surviving may not be good for sex," says Australian spider expert, Dr Marie Herberstein, of Macquarie University in Sydney.
+The classic example is the male peacock's tail, she says, which is good for attracting females but weighs him down and affects his chances of survival when being pursued by a predator.
+She says Kasumovic and Andrade have found that when it comes to the redbacks, maturing early is good for their sexual success but maturing later is better for survival.
+The study
+Kasumovic and Andrade studied how immature male redbacks develop in the presence and absence of females. 
+They found that when females are not around, the males develop into sexually mature adults slowly, growing into relatively large adults with lots of energy stores.
+This gives the male spiders a higher chance of survival when they set out on their search for female mates, the researchers say.
+But when male spiders are surrounded by females, they focus their energy on maturing quickly, ending up both smaller and leaner because they have spent less time foraging.
+Kasumovic and Andrade say growing up fast gives the spiders the best chance of being first to mate with the nearby females, something that is important considering the sex life of redbacks.
+Males redbacks only have one or two chances to mate before they are killed by the female, and mating is most successful when the female is a virgin.
+"Everybody always states that the small males are a by-product of them not being able to get enough resources, but we're showing that they're intentionally developing that way," says Kasumovic.
+Small and fat
+The researchers found that when both females and males are around, male redbacks also grow up fast and small. But they have more fat stores on their body than when other males were not around.
+The researchers suspect that this extra fat gives the males the endurance to compete with other males for the extended courtship rituals that females prefer.
+Males are supposed to pluck and vibrate a female's web strings for up to eight hours in the hope of gaining their favour.
+In the experiment, the males could not see or touch the females or males around them. This means the spiders were responding to pheromones, literally sniffing out their mates and potential competition.
+A choice of strategy
+Herberstein says the new research shows that male spiders choose which strategy to pursue depending on how they assess their environment as they're maturing.
+"Through this developmental plasticity, the males can tailor their development depending on the situation they find themselves in," she says.
+
+Playing violent video games can change the way you think, a study says
+Playing violent video games can make you think other people are out to get you, research shows.
+Dr Sonya Brady of the University of California, San Francisco, and Professor Karen Matthews at the University of Pittsburgh say their study shows that young men are more likely to see others' attitudes toward them as hostile if they've just played a violent game. 
+"You're kind of on the lookout for other people being rude to you," Brady says. 
+Brady and Matthews had a group of 100 male undergraduates aged 18 to 21 play one of two popular video games.
+One game involved car theft and bashings and the second one pitted the player in a race to get homework to school on time.
+In the non-violent game, players took the role of a parent and their task was to deliver their child's science project to school before it could be marked late.
+In the violent game, players took the role of a criminal, and were instructed by the mafia to beat up a drug dealer with a baseball bat. 
+Are you accusing me?
+After playing the games, study participants watched a scenario in which a teacher tells a class he suspects some students have cheated in a test.
+The teacher says he is very disappointed in those who have cheated but proud of those who did well. 
+The teacher then asks to see "Billy" after class. 
+The study participants were told to imagine themselves as Billy, and were asked how likely it was that the teacher was going to accuse them of cheating.
+Students who'd played the violent game were more likely to think they'd be accused of cheating, the researchers report in the Archives of Pediatrics and Adolescent Medicine. 
+More likely to approve of marijuana
+Brady says the study also shows young men are more likely to think it's acceptable to smoke marijuana and drink alcohol after playing a violent game.
+She says this suggests that violent video games make players more likely to throw caution to the wind, whether it's with regard to their own health or any other type of risky behaviour.
+"Parents have been told the message that violent video games and violent media in general can influence the likelihood that their kids will be aggressive," Brady says.
+"What this study suggests is that they might increase any type of risk-taking behaviour."
+Playing the violent game boosted young men's blood pressure, and appeared to have more of an effect on those who came from more violent homes or communities, the study says.
+But regardless of whether they grew up in a violent environment, the young men who had played the violent game were less cooperative and more competitive in completing an assigned task with another person, compared to those who played the non-violent game.
+The results show the potential for video games to change the way we think, Brady says.
+
+A pump that extracts heat from sewage is being used to warm homes
+Norwegians can now heat their homes and offices by flushing the toilet.
+The sewage heat pump plant, which began operating last week, uses fridge technology to tap heat from raw sewage and direct it back to the country's capital Oslo.
+Machines at the end of a 300 metre long tunnel in a hillside in central Oslo suck heat from the sewer and transfer it to a network of hot water pipes feeding thousands of radiators and taps in the city.
+Similar systems have been used in other parts of the world but the Norwegians say theirs is the biggest.
+"We believe this is the biggest heating system in the world using raw sewage," says Lars-Anders Loervik, managing director of Oslo energy company Viken Fjernvarme, which runs the plant. 
+The pump uses a system of compressors and condensers and generates 18 megawatts, enough heat to warm 9000 flats or save 6000 tonnes of oil a year, he says. 
+ Exploiting sewage
+Untreated sewage from toilets, bathtubs, sinks and rainwater from the streets flows into the system at 9.6&deg;C and comes out at 5.7&deg;C after heat is extracted with a refrigerant. 
+The energy goes to warming to about 90&deg;C the water in a 400 kilometre pipe system fed to offices and homes, from a temperature of 52&deg;C when it reaches the sewerage plant.
+Industrial waste burning plants also heat the water.  
+About a third of the heat energy comes from electricity driving the system and the other two-thirds is the heat from the sewer. 
+Dr Monica Axell, head of the International Energy Agency's heat pump centre, says the concept could be a feasible solution for many cities as long as they have the necessary infrastructure.
+The only problem with the system is that flow in the sewers tends to be irregular.
+Monday mornings between 4am and 6am are especially dry in Oslo because residents go to bed early on Sunday.
+But on weekends the flow is good, says project manager for the Oslo plant Oyvind Nilsen.
+"When people have been out to parties there's a lot of beer going into the sewer," he says. 
+Among other sewage energy projects worldwide, US scientists are looking to generate electricity from sewage-eating bacteria.
+"The microbial fuel cell work is going well, but we still are not out of the lab on this technology," says Professor Bruce Logan of Pennsylvania State University.
+
+More search results aren't the answer. We need targeted results, experts say
+Google's new search engine technology won't solve all the problems of finding what you need but it's a small step in the right direction, information retrieval experts say.
+The company has paid an undisclosed amount to license a new type of search algorithm, recently designed in Australia by University of New South Wales PhD student Ori Allon.
+The search tool, Orion, has been touted as the biggest thing in searching the web since the development of the Google page rank algorithm by two Stanford University researchers in the early 1980s.
+Little has been disclosed about the software because of commercial confidentiality.
+But the man who worked with Allon to market his research says the system will make searching the net faster and easier.
+"When you put in a query it comes up with a list of associated keywords that specify your search to a greater depth," says Andrew Stead, business development manager of the NewSouth Innovations, the commercial arm of the University of New South Wales.
+"It actually goes into sites and extracts ... text so you can just scroll down a single page and derive the information you were looking for.
+"Traditionally you've have to click through to the site, but this means you don't have to click through and find that the site's incorrect."
+Luxury cars or football?
+For example, a search for a particular model of luxury car comes up with where to buy one, a review of the car itself and an overview of the car manufacturer.
+Stead says the search is best suited to information-based queries, such as the rules of Australian Rules football, rather than finding the home page of the Australian Football League.
+But even Stead says it's not the end step in perfecting internet searches, which some research suggests cover as little as just 5% of the web.
+ "Search has got a long way to go before it's going to give us what we want and this is one step in that path," he says.
+Ranking pages
+Dr Peter Bailey is project leader of the CSIRO's information retrieval project and has been involved in designing a search engine designed for use within organisations.
+Like Stead, he says it appears that Allon's model has gone some way to addressing one of the biggest problems of searching the internet, which is how information is ranked.
+Bailey says search engines work by trawling the net for documents on public websites.
+The documents are then copied to form a sort of reverse index where words are linked to massive indexes of documents.
+This is why the key to successful searching is ranking the material to reflect the needs of the searcher, he says.
+Bailey we're still far from the perfect search engine, and current systems only address about 5% of the problems involved in trawling the web for information.
+The Holy Grail of internet searching includes tailoring searches to individuals, accessing the whole internet and providing the perfect answer, something he says may be as elusive as it is desirable.
+
+Graffiti is the modern equivalent of cave art, an expert says. Both are produced by young men with adrenaline and sex on their minds
+Testosterone-fuelled boys created most prehistoric cave art, according to a book by one of the world's authorities on this type of art.
+The theory contradicts the idea that adult, tribal shaman spiritual leaders and healers produced virtually all of it. 
+It also explains why many of the images drawn in caves during the Pleistocene, between 10,000 and 35,000 years ago, somewhat mirror today's artwork and graffiti, largely produced by adolescent males. 
+"Today, boys draw the testosterone subjects of a hot automobile, fighter jet, Jedi armour, sports, direct missile hit, etc - all of the things they associate with the adrenaline of success," says Professor R Dale Guthrie, author of The Nature of Paleolithic Art. 
+"I think the full larder [of] success of the excitement and danger of killing a giant bison or auroch in the Pleistocene was the equivalent of the testosterone art today," says Guthrie, who is an emeritus professor in the Institute of Arctic Biology at the University of Alaska Fairbanks.
+He says that many of the cave art images of animals are rather graphic, showing, for example, speared animals with blood pouring out of their mouths and noses. 
+But hunting and animals were not the only things on the cave artists' minds.
+Guthrie has also noticed that males were drawn with no defined sexual parts save for a simple line designating the penis. Few men were even represented, but the images of women in caves tell a different story. 
+"Female images dominate and are nude, almost every one full-figured above and below," says Guthrie.
+"Unlike the other animals, the sculpted, engraved and painted human females and female parts are sometimes done schematically, distilling and inflating the primary and secondary sex characters." 
+Learning to draw
+Guthrie also determines that several cave art images are incomplete, overlapping, brief and rudimentary, as though the people who created them were still learning to draw. 
+This type of sketching dominates cave walls, which also display a handful of works that appear to have been drawn by well-practiced artists, who were probably adults. 
+Perhaps the most convincing piece of evidence for the new theory consists of 200 handprints that were left in the caves next to the art.
+These prints were produced by people who chewed ochre, held up a hand, and then spit the colorful orange-yellow spew all over the hand, leaving a wall imprint. 
+Guthrie analysed the handprints and then compared the results with earlier research on male and female hands.
+The hand lengths, palm widths and the finger widths and lengths mostly match hands that would have belonged to boys aged nine to 17. 
+Some teen female handprints were identified in the caves, but young male prints were more common. 
+Other handprints resulting unintentionally from people leaning against muddy cave walls, as well as footprints, also suggest that young boys were creating the cave art, according to Guthrie. 
+Paul Martin, professor of quaternary biogeography at the University of Arizona, says he is inclined to agree with the new theory and findings.
+"[Guthrie] has an extraordinary knowledge of wild animal ecology globally, and especially in the northern hemisphere," Martin says.
+"In addition, he brings detailed knowledge of late Pleistocene fossils to his study of cave art. Finally, like many zoologists, especially those with children of their own, he is an astute observer of human behaviour.
+"If he finds that much cave art reflects teenage or preteen preoccupations, I am prepared to believe him," he says.
+
+This pampered pooch walks the same way as a greyhound or a labrador. But why is the US military interested?
+Labradors and dachshunds appear to waddle, while greyhounds seem to march by with a fast clip.
+But new research shows the basic mechanics behind dog walking is the same for all canines. 
+The discovery could lead to a better understanding of health issues related to the way dogs walk, like hip problems, the researchers say.
+And it could also result in improvements to four-legged, dog-like robots, which the US military is already investigating.
+"The big benefit would be to show how robot dogs should walk more efficiently," says lead scientist Dr Jim Usherwood, a researcher from the Structure and Motion Laboratory at the University of London's Royal Veterinary College.
+"Almost all robots require a large amount of power - much higher than an animal would use - partly because they tend to use bent legs. I show what would happen with stiff legs," Usherwood adds.
+Inspired by stiff-legged mechanical toys that can walk down hills, Usherwood and his team designed several different computer models for dog walking. The researchers then compared these models with observations of actual dogs on a treadmill. 
+Their simple, passive, stiff-limbed computer model best matched and explained the principles underlying dog walking. 
+The findings were recently presented at the annual meeting of the  Society for Experimental Biology in the UK. 
+Like controlled falling
+Walking for both bipeds and quadrupeds is like controlled falling because, with each step, the individual leans forward and is 'caught' by an outstretched limb.
+As a result, there is a stage when the body is high and slow, and a stage when the body is lower and faster, Usherwood explains. 
+"With a four-legged animal, this has broadly been observed before, but it had not been clear why and when these motions should happen," he says.
+"My passive model makes it much easier to understand when and why the body moves up and down and changes in speed." 
+The model also found that walking happens on relatively stiff limbs, unlike trotting, where a dog's legs function like springs and tend to bend more. 
+This is true for bipeds such as humans. But he says people put more energy into extending their legs, while dogs appear to power themselves with torque around their hips, similar to how weight is distributed on a bicycle. 
+Dogs, particularly older, arthritic ones, often suffer hip problems because if any two bones within the hip region lose their normal position, the abnormal areas can grind against each other with each step. 
+Over time, abnormally shaped bone can grow and inflammation sets in. Since one condition fuels the other, it becomes a vicious cycle.
+Usherwood hopes his model could help to clarify how this deadly cycle begins and worsens, which eventually may lead to improved diagnosis and treatment. 
+Harvard University scientists have come to similar conclusions regarding the mechanics behind dog walking.
+Russell Main, a Concord Field Station researcher, believes that dog legs work like two inverted pendulums, where mechanical energy is usually recovered with each stride. 
+Dr David Lee and Professor Andy Biewener, also at Harvard, have already built a robot resembling a headless dog, called BigDog, that uses similar principles. 
+According to Boston Dynamics, a research group involved in the project, BigDog so far has trotted at about 5 kilometres per hour, climbed a 35&deg; slope and carried about 54 kilograms.
+In the future, the US military, which is helping to fund the research, hopes to use BigDog for rescue operations and other possible fieldwork.
+
+If your sex life isn't all smiles and fireworks, are you sick or just going through a rough patch? And what's a normal sex life anyway?
+Consumers are being marketed drugs for premature ejaculation without good evidence there is a medical problem to be treated, an Australian conference heard this week.
+US-based psychologist and sex therapist Dr Leonore Tiefer, of the New York University School of Medicine, told the Inaugural Conference on Disease-Mongering in Newcastle this week, that premature ejaculation is "the next sexual dysfunction" to be marketed by the pharmaceutical industry.
+This concerns Tiefer because she says sexual difficulties are generally not biological problems that need medical treatment.
+"There's no sickness, there's no pathology, nothing is broken," she says. 
+She says when men and women are counselled about what is distressing them sexually, rapid ejaculation is of low importance.
+Tiefer says the way premature ejaculation is being marketed as a condition in need of treatment has "all the hallmarks of disease mongering". 
+First, she says, drug company-sponsored messages in the media have led to growing public awareness that premature ejaculation is regarded as a problem by experts who are measuring it, defining it and finding cures for it.
+These messages include "help-seeking" advertisements that urge people to "ask your doctor" about solutions to the problem. 
+"The disease-awareness campaign is in full force at this point," says Tiefer.
+What's normal?
+She says as a result people are now asking doctors what the normal speed of ejaculation is, and wondering whether they meet the normal standard.
+"The answer is there is no such thing as normal," she says. "There's a range. Some people are quick, some people are slow. Most people are in the middle."
+She says although there are no drugs yet specifically approved to treat premature ejaculation, doctors are treating the condition with available drugs that are known to slow down the speed of ejaculation.
+"Doctors are getting a lot of medical education about the off-label uses of these drugs," she says. "There are articles published, there are conferences organised around this and there are drug company-paid people going out there and saying you can use this for this."
+Tiefer says health and science journalists are also writing about premature ejaculation and the help available for it.
+Poorly defined
+Australian sociologist Dr Ross Morrow of the University of Sydney, who also spoke at the conference, agrees premature ejaculation is a "suspicious condition".
+"To me this is a condition that is a very questionable medical category," he says, adding that the condition is "poorly defined". 
+He says over the years there has been an attempt to define premature ejaculation according to the amount of time that lapsed, or the number of thrusts that occurred, before ejaculation occurred, but no agreement has ever been reached.
+Morrow says the American Psychiatric Association defines it as persistent and recurrent ejaculation either before a man has intercourse, during attempts at penetration or very shortly after intercourse begins, in a way that is distressing to him or his partner.
+And he says the definition relies on a clinician's judgement about whether the ejaculation is occurring too soon or not.
+Norms changing over time
+Morrow also says norms about when men should ejaculate during coitus are constantly changing.
+For example, he says, a study in 1948 by Alfred Kinsey discovered three-quarters of men ejaculated within two minutes of coitus and regarded this as acceptable.
+"He didn't think that was a dysfunction," says Morrow. "He actually thought that was a sign of men being sexually responsive."
+But Morrow says during the 1960s the period of time to ejaculation considered normal by experts was extended.
+He says this coincided with a belief that women's lack of sexual satisfaction during intercourse could be addressed if her male partner could take longer to ejaculate.
+Morrow also says different cultures have different norms about how long men should take to ejaculate, citing the case of one Melanesian culture that considers ejaculation after 15 to 30 seconds normal.
+Morrow says in Australia premature ejaculation is often mentioned in the same advertisements discussing erectile dysfunction, and is sometimes referred to under the banner of "ejaculatory problems".
+He says antidepressant drugs used to delay or inhibit ejaculation are being currently used in impotency clinics in Australia and sex therapists are also treating the condition using cognitive behavioural therapy.
+Female premature ejaculation?
+Both Tiefer and Morrow are also concerned about the notion of "rapid orgasm", the female equivalent of premature ejaculation.
+"I think it's part of a transformation of sex from a subjective experience into a concrete performance, almost like a sport with rules and goals and achievement standards," says Tiefer. 
+"So you can define very clearly whether your performance is up to part and in that way products can be provided for you to achieve performance ore even exceed those expectations."
+
+Caulobacter crescentus uses its stalk to stick to solid objects
+Harmless bacteria that live in rivers produce a biological superglue stronger than any ever measured, scientists say.
+Researchers reporting recently in the Proceedings of the National Academy of Sciences, say the microorganism Caulobacter crescentus sticks to surfaces three to four times more strongly than synthetic superglue.
+The bacteria holds the secret for understanding how to prevent harmful bacteria from sticking to human tissue and causing disease, the researchers say.
+It also may help to produce a nontoxic superglue that could be used for anything from a dental adhesive, to an industrial glue that works underwater, to a surgical glue. 
+"The advantage here is that these bacteria live in water and so they bind to all sorts of surfaces in water," says team member Yves Brun, professor of biology at Indiana University. "This means that this glue is very versatile." 
+Biologists including Brun regularly study C. crescentus as a biological model for understanding how other bacteria function.
+Over the course of other experiments, Brun realised the holding power of the tiny critters, which attach themselves to surfaces with a stalk-like appendage.
+Genes for stickiness
+To zero in on how they do it, Brun and his team began genetically manipulating the bacteria to remove specific genes needed to produce the adhesive. 
+Eventually, the scientists realised that variations of C. crescentus lacking the genes required to produce chains of sugar molecules at the ends of the stalks could not hold fast to surfaces. 
+The scientists determined that the polysaccharide is a critical component of the adhesive.
+They think that the sugar molecules are attached to super-sticky proteins, but they have yet to confirm which ones. 
+They also have indirect evidence that either there are other adhesive molecules involved or that the polysaccharide is somehow modified to make it stickier, says Brun.
+How strong is the glue?
+The researchers did, however, confirm just how tenacious the bacteria are.
+Jay Tang, an assistant professor of physics at Brown University and his team stepped in to help measure the force required to pull the bacteria off a flexible glass pipette. 
+The researchers found that a single bacterium could withstand a stress of 0.11 to 2.26 micronewtons.
+In other words, the amount of bacteria that fit onto an Australian 20 cent piece (or a US quarter) could withstand being pulled by a force of four to five tonnes, about the mass of an adult elephant.
+The team also found enzymes that work to unglue the bacteria from a surface.
+"The work by the group at Brown is exciting in its implications for better understanding natural adhesives and also in possible translation to new synthetic adhesives," says Professor Dennis Discher of the Biophysics and Polymers Lab at the University of Pennsylvania. 
+According to Brun, ultimately the bacteria would not be used as a glue itself, but to produce the adhesive.
+Before that can happen, the scientists have to pinpoint the genes required and devise a method for getting the bacteria to produce the glue in large quantities.
+
+Australopithecus anamensis fossils include teeth, upper jaws, hand and foot bones, vertebral fragments, a thigh bone and fragments of skull and jaw
+An international team of scientists has discovered 4.1 million year old fossils in eastern Ethiopia that fill a missing gap in human evolution. 
+The teeth and bones belong to a primitive species of Australopithecus known as Australopithecus anamensis, an ape-man creature that walked on two legs. 
+The Australopithecus genus is thought to be an ancestor of modern humans. Seven separate species have been named and Au. anamensis is the most primitive. 
+"This new discovery closes the gap between the fully blown Australopithecines and earlier forms we call Ardipithecus," says Professor Tim White, from the University of California, Berkeley, who's team reports its find today in the journal Nature. 
+"We now know where Australopithecus came from before 4 million years ago." 
+The fossils were unearthed in the Middle Awash area in the Afar desert of eastern Ethiopia. 
+The area, about 230 kilometres northeast of Addis Ababa, has the most continuous record of human evolution, the researchers say. 
+The remains of the hominid that had a small brain, big teeth and walked on two legs, fits into the one million-year gap between the earlier Ardipithecus and Au. afarensis.
+The famous fossil skeleton Lucy, which lived between 3.6 and 3.3 million years ago and was found in 1974, is an example of Au. afarensis.
+"It is fair to say that some species of Ardipithecus gave rise to Australopithecus," says White.
+Fossil find
+The fossils from about eight individuals include the largest hominid canine found so far, the earliest known thigh bone of the species and hand and foot bones. 
+The finding also extends the range of Au. anamensis in Ethiopia. Previous remains of the species were found in Kenya. 
+White says the large teeth suggest the hominid could eat fibrous foods and roots, compared to earlier species of Ardipithecus that had smaller teeth, which restricted their diet.
+Along with the hominid fossils, the scientists discovered hundreds of remains of pigs, birds, rodents and monkeys as well as hyenas and big cats which gave them an idea of the habitat in which they existed. 
+"Here, in a single Ethiopian valley, we have nearly a mile-thick stack of superimposed sediments and 12 horizons yielding hominid fossils. These discoveries confirm the Middle Awash study area as the world's best window on human evolution," White adds.
+
+The Mona Lisa has inspired many imitations, like this poster advertising contact lenses
+Hidden behind the Mona Lisa's enigmatic smile are millions of invisible dots, research shows.
+According to research presented recently at Italy's Uffizi Gallery in Florence, the Mona Lisa consists of countless of dot layers applied with a technique of microdivided brushstrokes. 
+The dot research was revealed at the exhibition "The mind of Leonardo - the universal genius at work", which runs at the gallery until January 2007.
+Jacques Franck, a consultant at the Armand Hammer Center for Leonardo Studies at the University of California, Los Angeles, says the technique is somewhat similar to pointillism used by the French neo-impressionists in the late 19th century. 
+"Examples of this microdivision of tones exist since the ancient Romans. Leonardo took an existing techniques, but used it to the extreme, like nobody else," says Franck.
+The painting technique is called 'sfumato', from the Italian word 'fumo', meaning smoke. And it produces an almost 3D effect, the result of the delicate brushwork that blends light, shadow, and contours.
+Da Vinci never really explained how he was able to blend shadow and light in such an imperceptible way. 
+The only reference to the sfumato technique appears in his notes on the painting.
+"Light and shade should blend without lines or borders, in the manner of smoke," he wrote.
+Applying science
+Franck examined Leonardo's works using what he calls an "archaeological approach".
+He took a close look at another da Vinci work, 'Drapery study for a seated figure', which hangs in The Louvre, and noticed that Leonardo used minute brushstrokes to produce the 3D effect of the draperies. 
+"The technique is visible, as he used tempera [a type of emulsion of oil and water, often using egg]. On the contrary, in oil painting traces would have been masked by a delicate velatura or glaze," Franck says. 
+Franck, an artist himself, has been copying Leonardo's works since he was eight.
+And Franck backed up his microdivision theory by reconstructing the Mona Lisa's eye through six steps, represented by panels on display at the Uffizi exhibition. 
+He started with a poplar panel, similar to the one Leonardo used to paint the Mona Lisa in 1503-1506. 
+Franck treated the panel with gypsum and animal glue, then painted an eye with a brush, but using black chalk.
+Then he applied a semi-opaque, diluted oil-based wash to soften the chalk lines and then retouched the details with microscopic brushstrokes.
+He had to apply many layers until they blended together. 
+According to Franck, details such as the smile and eyes contain between 30 and 40 brush strokes per millimetre. Essentially, Leonardo was working as a miniaturist would.
+"He may have made one square millimetre a day. This means it might have taken Leonardo about 10 years to complete the Mona Lisa," Franck says.
+Enigmatic smile
+Lisa di Antonio Maria Gherardini, the Mona Lisa, has been fascinating art lovers since her portrait was completed toward the end of the life of Leonardo, who lived from 1452-1519. 
+Attempts to solve the enigma around her smile, described by the 16th century artist and writer Giorgio Vasari as "more divine than human", have included theories that the noblewoman was happily pregnant, suffering from asthma, had facial paralysis or that the smile was the result of a compulsive gnashing of teeth.
+Franck's theory is raising a debate among art historians.
+"I find it absolutely untrue. Leonardo did use the sfumato, but his painting technique is also very firm. I have seen the Mona Lisa under a magnifying glass and really, I could not see any dot," says da Vinci scholar and UK professor of art history Martin Kemp, from the University of Oxford.
+Franck argues that it is scientifically impossible to distinguish the dots with a magnifying glass. 
+"Light penetrates each dot, producing reflection, diffraction, and diffusion. Thus, when you look at the painting, the surface appears homogeneous. No dot can be seen. Moreover, in my works the dots completely disappeared within three years. The same might have happened with the Mona Lisa," Franck says.
+How about x-ray evidence? 
+Indeed, x-ray images of Franck's copies are very similar to x-ray pictures of the master's works: they all show something similar to smoke. 
+"The layers of paint are so thin that x-ray simply goes through," Franck says. 
+According to the curators of the exhibition, Franck's hypothesis is "convincing". 
+"It is compatible with the material evidence of the Mona Lisa as analysed by the Louvre's laboratory," they write in the exhibition catalogue.
+
+Venus' south pole, by day and night. The left hand image is the view by day, showing sunlight reflected from the tops of clouds. The right hand image, taken using infrared sensors, shows a dynamic spiral cloud, with the darker regions corresponding to thicker cloud cover
+The newly arrived Venus Express spacecraft has relayed the first view of the planet's south pole, revealing a dark vortex and an odd cloud-type structure. 
+"We're already experiencing the hot, dynamic environment of Venus," says project scientist Dr Hakan Svedhem. 
+Venus Express captured its first images of its host planet the day on Wednesday, the day after it slipped into orbit following a five month journey.
+The European-built craft is expected to spend two Venusian days - which is more than a year on Earth - studying the planet's dense and turbulent atmosphere.
+The mission will attempt to learn why a planet so similar in size and composition to Earth ended up so vastly different. 
+Venus has an extremely thick and toxic atmosphere that traps heat more effectively than any other planet in the solar system. 
+Its surface temperature is hotter than Mercury, which orbits closer to the Sun, and its atmospheric pressure is similar to Earth's pressure about a kilometre beneath the ocean. 
+Although the new images are relatively low-quality - when the probe reaches its final orbit scientists expect more than 100 times better resolution - researchers are intrigued by the clear structures and unexpected details seen in the planet's atmosphere. 
+The Sun-lit images primarily show reflected light from Venus' cloud tops, down to a height of about 65 kilometres above the planet's surface. 
+The night view, which was taken using infrared sensors, shows a dynamic spiral of clouds in the lower atmosphere, similar to a structure previously seen at the planet's north pole. 
+The pictures were taken from a distance of about 200,000 kilometres. 
+Zooming in on Venus
+Venus Express is in the process of tightening its orbit, which will eventually reach as close as 250 kilometres above the planet's surface. 
+Venus Express is the first spacecraft to visit Venus since NASA's Magellan radar mapping mission of the 1990s.
+The probe is equipped with seven instruments, many of which are spares from Europe's ongoing Mars Express mission and the Rosetta comet probe. 
+Researchers hope to unlock the history and mechanisms of Venus' dense and toxic atmosphere. 
+They want to understand how the presence of carbon dioxide, water vapour and sulfuric gases trap heat in the planet's atmosphere, similar to how a glass greenhouse warms plants on Earth.
+
+Chernobyl surrounded by a crumbling concrete outer layer, which the international community hopes will by replaced by a sturdier steel jacket by 2012
+Twenty years ago, explosions at the Chernobyl power plant sent a huge radioactive cloud into the air in the world's worst civilian nuclear accident that still affects millions of people today. 
+On 26 April 1986, at 1.23 am local time, a series of explosions ripped through reactor four at the plant in the north of what is today Ukraine, near its border with Belarus.
+Radiation fell across much of Europe. 
+For days, the Soviet leadership refused to admit, either to its own people or to the world, what had happened less than 100 kilometres north of a major city, Kiev, and near the huge Dniepr River that crisscrossed Ukraine and provided much of its water supply. 
+Only after the news blackout ended were 135,000 people evacuated from the most affected areas around the plant. 
+To this day, Chernobyl fuels controversies over the use of nuclear power, attracts tourists and researchers, feeds fears of another release, continues to claim victims, and gobbles huge amounts of international funds. 
+An army of some 600,000 'liquidators' - firemen, soldiers and civilians - helped to construct a concrete sarcophagus meant to contain the reactor for 20 to 30 years before a more permanent structure could be built. 
+The fate awaiting these people and others exposed to radiation from the blast is one of the main controversies still surrounding the plant. 
+In its latest report on the disaster released in September, the UN estimates that fewer people will eventually perish than was initially predicted. 
+The report, the work of some 100 scientists from eight UN agencies, says up to 4000 will eventually die as a result of the accident, in addition to the nearly 60 people who have already died. 
+Environmental groups like Greenpeace reject the findings as "whitewash", collusion "with the nuclear lobby" and "insulting for the victims". They estimate that the death toll will be in the tens of thousands. 
+Psychological problems
+In addition to health effects like thyroid cancer, survivors also deal with psychological problems. 
+A study of more than 2000 liquidators by the Serbsky Psychiatric Institute in Moscow found that two thirds of them suffered from psychological illnesses. 
+"Considering their young age at the time of the accident, all of the negative effects have not appeared yet," says Galina Rumyantseva, who led the study. 
+Regions affected by the accident remain today both socially and economically devastated. 
+Some 350,000 people have been evacuated from the surrounding areas in all. Some 784,320 hectares of prime agricultural land remain ruined, as do 700,000 hectares of forest. 
+The UN estimates that the eventual price tag of the disaster will run to hundreds of billions of US dollars. 
+Today, the sarcophagus over reactor four is cracked and crumbling, raising fears that more radiation can be released. 
+Some 28 countries have pledged to chip in more than US$750 million toward the construction of a new 20,000 tonne steel case.
+The cover is expected  to cost between US$1 and $2 billion dollars and is hoped to be finished by 2012. 
+But it will take at least 100 years to safely get rid of dangerous fuel and debris inside the plant, says spokesperson Yulia Marusich. 
+The plant, whose last reactor was shut down for good only in 2000, continues to attract attention.
+Tourists come to gawk, while researchers come to observe the remarkable flourishing of flora and fauna. 
+Hundreds of mostly elderly people who lived in villages around the plant have ignored government restrictions and warnings of radiation to resettle in the 30 kilometre exclusion zone around the plant, raising animals and eating fruits and berries from the radiation-soaked land. 
+The final effects from the series of explosions that occurred in the early hours at a Soviet nuclear power plant in 1986 may not be known for years, scientists say. 
+"We may not see anything today, but genetic modifications can appear in 20, 50 years," says Rudolf Alexakhin, director of the Agricultural Radiology Institute in Moscow.
+
+Workers set up the dig at Visocica Hill to look for evidence of an ancient pyramid, the so-called Bosnian Pyramid of the Sun
+Excavation work has started north of Sarajevo on what a Bosnian explorer says are Europe's first pyramids. 
+A group of experts explored the narrow entrance of a 3.8 kilometre tunnel believed to lead to one of the two hills resembling pyramids, about 30 kilometres from the Bosnian capital. 
+As residents of the nearby town of Visoko eagerly watched, digging began on one of 10 sites, 20-by-50 metres, on slopes of a hill covered by vegetation. 
+"Initial observations showed that the tunnel was man-made," says geologist Nadjia Nukic after examining the initial unblocked section of the tunnel. 
+Last year Semir Osmanagic, a self-styled Bosnian explorer, started initial investigations in the area, convinced the 'constructions' on Visocica and Pljesivica hills were the work of builders from an unknown civilisation. 
+He says further research using satellite pictures has provided more evidence for his case.
+The images show the hills cooled a lot faster than their surroundings, he says, proving the substance of the structures was less dense and therefore probably made by humans. 
+"With the paucity of contrary evidence, the hills are presumed to be anthropogenic structures of potentially colossal proportions," says Bosnian geophysicist Dr Amer Smailbegovic.
+The explorers, who are expected to be joined by an Egyptian archaeologist and a geologist later in the year, hope to find stone blocks, or the steps of the 'pyramids'. 
+Osmanagic, who wears an Indiana Jones-like hat and clothing and says he sharpened his eye for archaeology on numerous trips around the world, says the two structures are precisely aligned with the four points of the compass. 
+On the outskirts of the town, Visocica Hill, which Osmanagic refers to as the Bosnian Pyramid of the Sun, stands some 220 metres high, with a square base of more than 400 by 400 metres. 
+Osmanagic says he sees astonishing similarities between the structures and Mexican pyramids dating back to about 200 AD, which also come in pairs, one believed to represent the Sun and the other the Moon. 
+The excavation work, led by a recently established foundation of local archaeologists and volunteers, will last for 200 days.
+The first results would be known in three weeks, Osmanagic says. 
+The director of the Visoko Historic Heritage museum, Senad Hodovic, says he is no sceptic.
+"The pyramids are obviously the work of man. But we need proper and serious analysis to show who built them and when." 
+Hodovic says he has spent years urging authorities to support archaeological research on the plateau of the hill, which is recorded in historic annals as the site of a medieval Bosnian town. 
+He says the shape and monumental size of the structures is not typical for Bosnian constructions of the Middle Ages. 
+Visoko, a small town that has been slowly dying from economic decline since Bosnia's 1992-95 war, is hoping what has been dubbed the "the new wonder of the world" will offer it a brighter future.
+Pyramid-mania seems to have caught everyone. 
+Local souvenir shops selling oriental style coffee pots and plates now offer slippers, ceramic coin-boxes, t-shirts and brandy with pyramid logos.
+
+Seb the German shepherd smells sheep poo for a living
+A sniffer dog has been trained to tell which sheep have parasitic worms, Australian researchers show.
+The dog's skills will be used to develop an electronic handheld 'sniffer' device to detect gastrointestinal nematodes in sheep.
+The parasite detection initiative has the potential to save the Australian sheep industry millions of dollars a year, say agricultural scientists at Melbourne's La Trobe University.
+Internal parasites are a constant headache for sheep farmers because they cause serious production losses.
+They can interfere with a sheep's wool and meat growth, and make the animal weak and susceptible to other diseases. They can even kill.
+Anti-parasitic drugs have been the weapon of choice for a number of years, however many parasites have become resistant to the drugs.
+So the researchers tried something different.
+"Scents, and the use of sniffer dogs to detect them, are used to determine the presence of a number of substances," says chief investigator Associate Professor Mark Sandeman. 
+"So we set out to ascertain whether the presence of intestinal parasites in sheep could be detected by their scent."
+It seems they can, with Seb the female German shepherd being trained to detect parasite-infected sheep droppings by its odour with 80-90% accuracy.
+"We used [Seb] in a classic training sense; just as dogs are trained to detect drugs at airports, we trained [Seb] to detect parasites," he says.
+Bags of infested poo were placed among bags of non-infested poo and Seb was trained to pick out the infested sample.
+The whiff of parasites
+Sandeman says it is too early to say exactly which chemicals, or groups of chemicals Seb is sniffing out.
+"We don't know exactly what the dog is sniffing but we're picking up some differences in terms of chemical signatures that would suggest there are a number of different compounds that are changed between infected and uninfected sheep," he says.
+The researchers are now working on developing an electronic handheld 'sniffer' device similar to those used in the food manufacturing industry. 
+They are confident they will have a prototype within five years.
+"We thought about training dogs to use on farms, but [there were many] technical difficulties. So instead we thought it would be better to have some small device that farmers could use," Sandeman says.
+He envisages a farmer holding the sniffer device near the rear end of sheep or near poo.
+Eventually, the detector might be refined using biosensor technology and sheep may be checked automatically for parasites, he says.
+The Australian Sheep Industry CRC is funding the work.
+
+Hello Mr Personality! Researchers are learning that squid have distinct character traits
+Squid have personalities that appear to be passed down from parent to offspring, says an Australian researcher.
+But those traits can be modified by environment, says Dr David Sinn, who will present his research at the Australasian Association for the Study of Animal Behaviour conference in Sydney this week.
+Sinn, a research fellow at the University of Tasmania, observed behaviour in the southern dumpling squid (Euprymna tasmanica), which is found in waters around South Australia, Victoria and Tasmania.
+In general, these squid tend to be solitary, unromantic animals with a propensity to cannibalise their neighbours and take sexual favours by force, he says.
+Within that profile Sinn found some squid are shy, retiring, cautious types while others are bold, assertive and adventurous.
+"It turns out some squid are bolder than others," he says.
+"For example, when presented by a threatening stimulus they attack the stimulus or are ambivalent to it.
+"Others are shyer, they don't inspect a threat, they back up, they flee."
+Assertiveness training for squid
+Previous research suggests these character traits in squid are up to 30% hereditary, he says.
+But there's evidence that some squid can adapt to their environment by learning to either temper their overconfidence or shake off their shyness.
+Sinn says squid and other cephalopods like octopuses and cuttlefish are relatively intelligent and, relative to body size, have brains the size of cats.
+This is probably to compensate for the loss of their protective shells during evolution, he says, with more brain capacity needed to protect their vulnerable bodies from predators.
+Population dynamics
+Sinn says understanding the ecology and evolution of personality provides a key to understanding what drives animal populations.
+He says it's unclear which personality traits confer an evolutionary edge, although it appears that having a mix of personalities is essential for a population to survive a disturbance.
+"Individual behaviour is going to determine how far [an animal population] disperses, its growth rate, how well it survives and potentially how it reproduces, so all these things are driving population dynamics," he says.
+"If you want to know how to predict population abundance maybe we need to know more about individual behaviours and how they're going to react to environmental change."
+Squid lovers
+Sinn's next project is to investigate the role of personality in the sex life of squid.
+He says mating in the squid world is forceful on the part of the male but females play a role in choosing to associate with prospective mates or in attempting to rebuff unwanted advances.
+He says early evidence suggests bolder females prefer bolder males while shy females are less choosy.
+Sinn also intends to look at personality in lizards.
+
+Web developers and doctors running clinical websites need to be aware of possible misuse of their online images, US doctors warn
+Porn seekers are finding a new source of online images, doctors have discovered.
+They're downloading images of diseased genitalia from dermatology websites, sites that were originally set up to educate doctors.
+Dr Christoph Lehmann and colleagues, from Johns Hopkins University in Baltimore, noticed a marked jump in queries for images of genital areas from their searchable archive of clinical photographs.
+They investigated and published their results in the latest issue of the Journal of the American Academy of Dermatology.
+The researchers assessed request patterns received by the site over 6 months, in terms of diagnosis, age group and anatomical site. 
+Of the more than 7800 dermatological images available on the site, 5.5% involve genital regions. But 12% of queries for a specific diagnosis involved a genital area.
+Also 37% of the requests for an anatomical site involved a genital region, and 12% of the 10,000 free text queries were for images of genitalia. 
+In searches that specified both an age group and an anatomical site, images involving children were 48% more likely to be requested than those involving an adult. 
+An analysis of the top 43 referring sites to the dermatology service revealed that 21% were pornographic or fetish sites. But these sites only accounted for 14.3% of all 141,285 referrals. 
+"Developers of online clinical image libraries containing potentially sensitive health information on topics such as sexuality and anatomy must be aware of issues beyond technical and domain knowledge," the authors say.
+"Anonymous misuse of collaborative archives must be anticipated, addressed and prevented to preserve their integrity and the integrity of the learning communities they support."
+
+Neurologists say people whose dreaming spills over into wakefulness may be prone to near-death experiences
+The brain's tendency to occasionally blur the line between sleep and wakefulness may help explain the phenomenon of near-death experience, preliminary research suggests. 
+It's been an open question as to why some people see bright light, feel detached from their bodies or have other extraordinary sensations when they are close to dying or believe they might die. 
+Some people view these so-called near-death experiences as evidence of life after death, and many neurologists have considered the phenomenon too complex for scientific study. 
+But the new research, published in the journal Neurology, implicates the blending of sleep and wake states as a biological cause. 
+Researchers found that adults who say they've had such an experience are also likely to have a history of what's called REM intrusion, where aspects of the dream state of sleep spill over into wakefulness. 
+People may, for example, feel paralysed when they first wake up, or have visual or auditory hallucinations as they fall asleep or awaken. 
+Of the 55 study participants who've had a near-death experience, 60% have also experienced REM intrusion at some point in their lives. That compares with 24% of 55 adults in a comparison group. 
+Arousing the body
+The findings suggest that the brain's arousal system predisposes some people to both REM intrusion and near-death experience, according to the study authors, led by Dr Kevin Nelson, a neurologist at the University of Kentucky in Lexington. 
+This arousal system, Nelson says, regulates not only REM sleep, but also attention and alertness during waking hours, including during dangerous situations. 
+And many of the features of REM intrusions, he says, parallel those of near-death experience. 
+During REM sleep, visual centres in the brain are highly active, while the limb muscles are temporarily paralysed.
+So REM intrusion during peril could promote the visions of light and sensation of "being dead" that people often have during a near-death experience, according to Nelson. 
+Not the whole story
+Other evidence supports a role for REM intrusion in near-death experiences, he says.
+One important fact, Nelson notes, is that stimulation of the vagus nerve, which connects the brain stem to the heart, lungs and intestines, triggers REM intrusion. And heightened activity in this nerve is sure to be part of the body's "fight-or-flight" response to danger. 
+Still, Nelson says he doesn't think REM intrusion will turn out to be the "whole explanation" for near-death experience, and the findings shouldn't detract from the meaning people have taken from their experiences. 
+"My work is spiritually neutral," Nelson says, noting the research can only look at how the brain contributes to near-death experience, and not why the phenomenon occurs. 
+"The 'why' can't be addressed by scientific inquiry," he says.
+
+Grooming is important to cattle but would they use a hairbrush if they had hands?
+Beef cattle use tools to keep their coats healthy, says an Australian researcher, suggesting they are more than all brawn and no brains.
+Animal behaviour scientist Bob Kilgour, who works for the New South Wales Department of Primary Industries, observed the grooming behaviour of various breeds of beef cattle at pasture on a number of properties over several days.
+He found they spend about 3% of their day grooming and preening themselves, even in the absence of parasites.
+They mainly use their tongues and hind hooves to groom the rear end of their bodies, Kilgour says.
+But they also use inanimate objects like trees, branches, fence posts and stumps to get at areas they can't reach, he says.
+"They'll walk up to fallen tree limbs which have protruding branches and groom around their eyes," he says.
+"So they're making very finely controlled motor movements to groom around sensitive parts of their body."
+Kilgour will tell the Australasian Association for the Study of Animal Behaviour conference in Sydney this week that this deliberate choice of different kinds of objects suggests they are being used as tools.
+He says this is a bold suggestion because the definition of tool use conventionally relies on an ability to hold and manipulate objects.
+"These are animals that can't pick things up and manipulate them, but nonetheless they are making decisions about what they are going to use to groom their bodies," he says.
+"I'm postulating this could redefine our idea of tool use.
+"It's difficult to relate this to intelligence but I'd just like to say there's a lot more going on up there than we really know about."
+Comparisons with similar species
+Kilgour compared grooming behaviour of beef cattle with undomesticated, but related, species including bison, water buffalo, banteng and eland.
+He found similar grooming patterns.
+This suggests an evolutionary purpose for grooming, Kilgour says. For example, maintaining the integrity of their coat may protect against invasion by parasites, bacteria or grass seeds.
+"If you find this behaviour occurs in closely related species you can say this confers some survival advantage on animals, therefore it's a necessary behaviour," he says.
+"So in production systems, like feedlots, where we try to stop animals grooming because we don't want to push the fence posts over, we may be thwarting what is a valuable natural behaviour."
+He says attempts to prevent grooming may therefore be misguided and a denial of the animal's right to express normal behaviour, one of the central elements of animal welfare.
+
+This new type of brain-machine interface could replace joysticks in online gaming or be used as a communication tool for pople who cannot speak or sign
+A computerised keyboard that translates electrical impulses from brainwave signals into letters and words could be available in the next five years, German researchers say.
+In the short term, the technology will allow its developers, from the Fraunhofer Institute and the Charit&eacute; University Hospital in Berlin to watch a brain function in real time. 
+But in the long term, such a brain-machine interface could replace the joystick in electronic gaming or serve as a communication tool for people unable to speak or sign. 
+"We are dreaming of something like a baseball cap with electrodes in the cap that can measure the brainwaves," says one of the scientists behind the project Professor Klaus-Robert M&uuml;ller of the Fraunhofer Institute. 
+"People could just put on the cap and have a wireless connection from these electrodes to a computer and they can play video games." 
+Measuring brainwaves
+That vision, says M&uuml;ller, will require advances in electrode technology that allow the tiny, metal sensors to pick up electric signals from brainwave activity without making contact with the skin. 
+For now, M&uuml;ller and his colleagues are still somewhat constrained by the conventional electrode cap, which looks like a swimmer's cap embedded with 64 or 128 contact points and a web of wires leading to a computer. 
+Each electrode embedded in the cap must be smeared with a conductive gel before the cap is fitted properly to a person's head, a process that can take 30 minutes to an hour. 
+M&uuml;ller and his team's technology involves special software. 
+Once the electrode cap is in place, the person must calibrate the computer to their individual brainwaves. 
+Whereas other research projects may require a person to spend 100 hours practising with the machine before calibration is finalised, the Fraunhofer system takes only 5 minutes. 
+"The Berlin group is very strong and focused on the computer learning the pattern," says Robert Leeb, a brain-computer interface researcher at Graz University of Technology in Austria. 
+Leeb works in a team developing a machine that propels a person through a virtual environment based on brain signals. 
+Imagine moving your hand
+During calibration with the Berlin group's technology, the person imagines moving his left or right hand.
+The signals picked up by the electrodes are processed in a specially written computer program that filters out signals from thoughts not related to moving the object and homes in on the brain activity responsible for the imagination of movements. 
+Once the person is in sync with the computer, he can imagine moving his hands or feet or rotating an object to trigger an action on the screen. 
+"In the brain, there is one specific area on the cortex that is active during left hand motor imagery and another one that is active during right hand motor imagery," says team member Dr Benjamin Blankertz. 
+"These mental tasks are discriminated by their brain activity patterns and can thus be used for brain-computer interface control."
+Additional computer screens present various data indicating brain activity, which the team monitors closely. 
+The researchers' goal is to capture and display many more psychological measures, such as those that reveal cognitive workload, attention, stress and vigilance. 
+The work could open the door on a wealth of information about how the brain functions, not to mention improve how it controls images on-screen with just a thought, the researchers say.
+
+Banning the fluoroquinolone class of antibiotics in animal feed means humans are more likely to respond to these powerful antibiotics if they need them
+Reducing the use of antibiotics in food-producing animals leads to less drug resistance in humans, an Australian study confirms for the first time.
+Researchers examined samples from 585 people with gastroenteritis due to the nation's most common bacterial cause of foodborne disease, Campylobacter jejuni.
+Tests identified a low level of resistance to the fluoroquinolone group of antibiotics, which Australia has banned in food-producing animals like poultry.
+One investigator, senior lecturer in epidemiology at the Australia National University in Canberrra, Dr Mahomed Patel, says flouroquinolones are powerful, newer generation antibiotics that should be reserved for "pretty severe infections in humans".
+The study found that only 2% of the Australian-acquired campylobacter infections were resistant to ciprofloxacin, a type of flouroquinolone. 
+In countries that allow fluoroquinolones to be used in animals, ciprofloxacin resistant strains are up to 15 times more common in humans, studies show.
+Drug resistance could make these infections hard to treat, lengthen bouts of diarrhoea and increase risk of serious or fatal illness.
+"The very low level of ciprofloxacin resistance in C. jejuni isolates likely reflects the success of Australia's policy of restricting use of fluoroquinolones in food-producing animals," researchers say in a paper to be published in the journal Clinical Infectious Diseases.
+Those tested were from Queensland, South Australia, Victoria, Tasmania and Western Australia, states that require reporting of patients infected with the bacteria, and were hospitalised with gastroenteritis or remained in the community.
+Patel says it is unknown why ciprofloxacin resistance ranged from 0% among Tasmanian patients to 8% in infected Victorians.
+But as expected, there were much higher rates of resistance to other antibiotics among Australian-acquired infections, especially those more commonly used by people in the community.
+International evidence
+He says this is the first Australian study to support evidence seen in countries such as Sweden and Norway that banning use in animals means low rates of fluoroquinolone-resistant campylobacter infections in humans. 
+"It confirms Australia has remained relatively free of problems because we've never used these antibiotics in animals; avoiding animal use has prevented resistance in humans," Patel says.
+Those infected outside Australia were more likely to have a resistant strain, especially if they had travelled to Asia. 
+Reasons could include contact with an infected person or eating meat from an animal with the resistant bacteria, Patel says.
+In Australia causes could include medical treatment with the antibiotics, eating imported contaminated food or acquiring resistance in hospital.
+
+The newly discovered dinosaur looked like T-rex, pictured here, but had a longer, narrower skull and shorter, blade-like teeth
+Remains of an enormous species of carnivorous dinosaur, longer than all other previously identified meat-eating dinos, have been found in Argentina, scientists say.
+Researchers announced that the newly discovered meat muncher Mapusaurus roseae belongs to a group of gigantic carnivorous dinosaurs called carcharodontosaurids.
+This group includes Giganotosaurus, the largest meat-eating dinosaur to ever walk the Earth. 
+The discovery of the new dinosaur in western Patagoniais is published in the latest issue of the journal Geodiversitas. 
+Palaeontologists say Mapusaurus was more than 12 metres long and had a shinbone that was longer than that of Giganotosaurus.
+But the current record-holder retains its "largest" title because Giganotosaurus would have been wider and heavier than Mapusaurus. 
+Nevertheless, the new dinosaur would have been an intimidating creature, especially when it was part of a group.
+Hundreds of bones
+Researchers found hundreds of Mapusaurus bones dating to 100 million years together in a pack that would have included 5 metre long juveniles and adults which were more than 12 metres long. 
+"This is arguably the nastiest thing ever found, as it is the first pack found for giant meat-eating dinosaurs," says 'Dino' Don Lessem, who participated in the dig and helped to fund it.
+Lessem, a dinosaur expert who was a consultant on the film Jurassic Park, says that Mapusaurus would have lived at the same time as the largest animal that ever lived, Argentinosaurus, which was a 38 metre long plant-eating dinosaur. 
+"In a pack, [Mapusaurus] could take down this herbivore despite its weight - 10 times [more than] even this largest of meat eaters," he says. 
+Like T-rex
+Philip Currie, who also worked on the excavation and is a professor of biological sciences at the University of Alberta, says the new dinosaur somewhat resembled Tyrannosaurus rex. 
+"Mapusaurus looked something like T. rex but had a longer, narrower skull," Currie explains.
+"Its teeth were shorter and more blade-like. The teeth and long skull were better adapted to biting big chunks of meat out of sauropod dinosaurs. T. rex, on the other hand, had longer, thicker teeth for biting through the bones of its prey." 
+The palaeontologists therefore think the newly discovered carnivore both scavenged and hunted for meat. 
+Hunting in packs
+Dr Rodolfo Coria, who also worked on the excavation and is a palaeontologist at the Carmen Funes Museum in Argentina, says that Mapusaurus may have been unique among carnivores in that it seemed to live a more social life as it was found in a pack.
+T. rex and virtually all other carnivorous dinosaurs usually are solitary specimens, suggesting they mostly lived and hunted alone. 
+Coria says it is possible the big meat eaters evolved different habits for each species, and Mapusaurus simply may have been more social. The pack even appears to have passed away together in a mass die-off. 
+Dr Michael Ryan, curator and head of vertebrate palaeontology at the Cleveland Museum of Natural History, examined the dinosaur bones on a recent trip to Patagonia. He agrees with the other palaeontologists. 
+"This new discovery helps us better understand the diversity of giant carnivorous dinosaurs," says Ryan.
+"Even more interesting is the fact that the find contains the remains of multiple individuals of different sizes and ages."
+
+The new ground-based telescope will give images 10 times crisper than the Hubble Space Telescope
+Australian astronomers have joined a consortium building the world's largest telescope, which from 2015 will help scientists understand the evolution of the universe.
+The Australian National University has become equal partners with eight US institutions to design the US$500 million (A$671 million) optical and infrared Giant Magellan Telescope.
+The new telescope is to be built in Chile and will consist of six mirrors surrounding a central mirror, with each mirror 8.4 metres across.
+At an overall diameter of 21 metres, the new telescope will be the first of a generation of so-called Extremely Large Telescopes designed to probe the depths of the universe.
+"The largest telescopes that astronomers have access to right now have diameters between 8 and 10 metres," says Professor Penny Sackett, director of the university's Research School of Astronomy and Astrophysics, based at Mount Stromlo in Canberra. 
+"Extremely Large Telescopes have diameters of 20 to 30 to 50 metres."
+Sackett says the light-gathering power increases with the square of the diameter of a telescope.
+"When you go from an 8 metre to a 24 metre [telescope] you've actually increased your light-gathering power by a factor of nine not by a factor of three."
+Light from distant stars
+She says the telescope's enormous diameter will allow it to detect light from the most distant stars in the universe.
+The light has taken so long to reach Earth it is almost the age of the universe which means it gives astronomers a picture of the universe right after it was born, says Sackett.
+She says the Giant Magellan Telescope will be the first telescope to directly detect light from planets that are just forming around other stars.
+The telescope will also allow astronomers to study dark matter and dark energy, which influence the geometry of the universe.
+"Dark matter and dark energy are the forces that tug and pull on the fabric of space-time. They determine how the universe evolves over time," she says.
+Clear focus
+Sackett says the telescope will have "adaptive optics", new technology that undoes the blurring effects of the Earth's atmosphere. 
+"The mirrors move very quickly to put the light rays back in the right place by bouncing them at slightly different angles," she says.
+"The Giant Magellan Telescope should be able to take pictures that are 10 times crisper, 10 times sharper, 10 times more detailed that the Hubble Space Telescope."
+Partnership in the new telescope will give Australian astronomers access to an Extremely Large Telescope, which, according to the decadal plan for astronomy, is one of the two items Australian astronomers say are the most important to their future a decade from now.
+Sackett says that Australian industries and academic institutions could also benefit from contracts to design and build instruments for the new telescope.
+Other members of the consortium are the Carnegie Institution of Washington, Harvard University, Massachusetts Institute of Technology, University of Arizona, University of Michigan, Smithsonian Institution , University of Texas at Austin and Texas A&M University.
+
+When black holes collide, they spiral towards each other then shed vast amounts of energy as space-ripping gravity waves
+Powerful ripples that rend the fabric of space as black holes collide have been simulated for the first time by a supercomputer, finally giving astronomers something specific to watch for with new gravity wave telescopes. 
+Black holes, collapsed stars tens to billions of times more massive than the Sun, are believed to merge fairly often in the cosmos, as they get trapped by each other's gravity. 
+When it happens, they spiral towards each other and shed up to 40% of their energy in the form of powerful, space-torturing gravity waves, according to the new simulation. 
+These waves propagate through the universe and researchers say the waves ought to be detectable with the right equipment.
+"For years we didn't know what to expect," says Dr Joan Centrella, chief of the Gravitational Astrophysics Laboratory at NASA's Goddard Space Flight Center in Maryland. 
+The researchers used the world's fourth-fastest computer, NASA's Columbia supercomputer, to crunch the numbers in some of Einstein's toughest equations regarding black holes.
+They've come up with a basic gravity wave signature of a black hole merging process from start to finish. 
+"Now we have Einstein's prediction," she says. "This is a conceptualisation that we didn't have until now." 
+Computer power
+The new gravity wave simulation is the culmination of three decades of research that, until recently, required more computer power than was available.
+The results are being published in the journals Physical Review Letters and Physical Review D. 
+"For a long time they'd just crash and burn," she says of earlier computerised attempts to run Einstein's equations on the theory of general relativity. 
+In the end, it took a fifth of Columbia's parallel computer processors about 80 hours to crunch the complex 90-year-old equations.
+Added up processor-by-processor, the calculations took more than 18 years of processor time, Centrella says. 
+The researchers were pleased to discover one of their results.
+Regardless of the different possible orbits and speeds two black holes have when they begin to merge, they end up producing the same signature wave patterns as they near the end of their collision, Centrella says.
+That should make them pretty easy to identify. 
+The next step will be to detect some actual gravity waves and see if they match the simulation. That will be, in effect, one tremendous test of Einstein's work on black hole theory, says Centrella. It will also mark the genuine birth of a whole new field of astronomy.
+"Black holes play a key role in gravitational wave astronomy," says astronomer Professor Peter Saulson of Syracuse University in New York. "They will be the primary source of gravity waves." 
+Searching for gravity waves
+Saulson works on the Laser Interferometer Gravitational Wave Observatory (LIGO) in Hanford, Washington, which started searching the skies for gravity waves late last year. 
+LIGO, with its 4 kilometre-wide antenna, ought to be able to detect gravity waves from the collisions of smaller black holes, says Saulson. 
+As for the far larger supermassive black holes found at the centres of galaxies, their gravity waves will require a space-borne observatory that can detect much lower frequency gravity waves, he says. 
+That's the goal of NASA's Laser Interferometer Space Antenna, which will have three spacecraft 3 million miles apart and linked by lasers, due to be launched in 2015.
+
+Huge underground Antarctic lakes, like Lake Vostok pictured here, are connected by fast-flowing underground rivers that stretch for hundreds of kilometres
+Scientists have found huge, powerful rivers that may connect subglacial lakes deep under the Antarctic ice.
+UK researchers who discovered the plumbing system that moves water hundreds of kilometres say it challenges the notion that the lakes under the Antarctic ice evolved independently and could support ancient life. 
+"Previously, it was thought water moves underneath the ice by very slow seepage," says Professor Duncan Wingham of University College London (UCL) who headed the research team. 
+"But this new data shows that, every so often, the lakes beneath the ice pop off like champagne corks, releasing floods that travel very long distances." 
+Scientists had plans to drill through the ice to take samples from the lakes but were worried about contaminating them with new microbes. 
+"We had thought of these lakes as isolated biological laboratories. Now we are going to have to think again," Wingham says.
+The research, reported today in the journal Nature, also means that water from the Antarctic lakes, which were first discovered in the 1960s, could have flowed into the ocean in the past and could do so again. 
+About 150 subglacial lakes have been discovered in Antarctica but researchers believe there could be thousands. 
+Lake Vostok, at 15-20 million years old, is thought to be the oldest.
+Looking at satellite images
+Scientists from UCL and the UK's Natural Environment Research Council Centre for Polar Observation and Modelling found the rivers by examining changes in measurements taken by the European Space Agency ERS-2 satellite of a region in East Antarctica known as the Dome Concordia. 
+They noticed that the ice surface was 3 metres lower over one subglacial lake but it bulged by 1 metre at two other subglacial lakes about 290 kilometres away.
+They suspect these changes show a flow of water from one subglacial lake to the others and calculate 1.8 cubic kilometres of water would have moved over 16 months.
+"The lakes are like a set of beads on a string, where the lakes are the beads connected by a string or river of water," says Wingham. 
+The scientists believe when the pressure in one of the lakes increases, a flood fills the next bead down the string.
+But they do not know whether the flow of water that melts ice causes a chain reaction down the string.
+A mere drop
+Iceland has underground lakes that fill quickly and flush out, says Canadian researcher Professor Garry Clarke, from the University of British Columbia.
+But Clarke says, in the same issue of Nature, they discharge water 100 times faster than in Antarctica. 
+"The actual discharge [in Antarctica] was hardly catastrophic," he writes.
+And the Antarctic outflow is "miniscule" compared with the megafloods of the last Ice Age.
+Clarke writes how outflows from glacial Lake Missoula in what is now North America was 200,000 times more powerful than the UK researchers found in Antarctica.
+
+Young children are being medicated for an illness that some psychiatrists say doesn't exist
+Children as young as two years old are being inappropriately diagnosed and medicated for bipolar disorder, says a UK psychiatrist.
+Professor David Healy of Cardiff University told the Inaugural Conference on Disease-Mongering recently in Newcastle, Australia, that increasing numbers of children are being treated for the condition with drugs that carry serious side-effects, without evidence the condition exists in that age group.
+Healy says bipolar disorder is a condition in which someone's mood swings between highs and lows and in its most serious form this can lead to acts of suicide.
+He says until recently most people believed the illness only affects older teenagers or adults but the diagnosis is now being applied to young children, particularly in the US.
+He says children as young as two who are "tricky to handle, overactive or difficult in some way" are being diagnosed with bipolar disorder.
+And he says they are increasingly prescribed drugs known as mood stabilisers, which are used to treat the condition in adults and have serious side-effects.
+He says American Psychiatric Association (APA) diagnostic guidelines specify that periods of highs and lows should last for weeks at a time at least.
+But he says children being diagnosed as having bipolar disorder have moods that go up and down during the course of a day.
+"Every kid's mood goes up and down during the course of the day," he says.
+Healy says advocates of using the diagnosis on children say the APA guidelines should be changed.
+"The response from most of the rest of the world is that the Americans have gone hysterical."
+Expanding treatment
+Healy believes that the diagnosis of children with bipolar disorder is part of a general trend towards increasing the number of people treated with mood stabilisers, which he says have risks that are downplayed and benefits that are overplayed.
+He says while a very small percentage of people have the serious form of bipolar disorder that might warrant medication, recently people with relatively mild mood swings have been treated, and this is now including children.
+Healy says this spread of diagnosis is reflected in the increasing number of books on bipolar disorder aimed at clinicians, parents and children.
+What he describes as a "watershed" book called The Bipolar Child: The Definitive and Reassuring Guide to Childhood's Most Misunderstood Disorder sold 70,000 hardback copies in its first six months, indicating huge support for the diagnosis, he says.
+"[And books for children] look for all the world like versions Little Red Riding Hood or Cinderella or whatever," he says.
+"They come in the same pastel colours, they show scenes of a kid who was getting into trouble and then being helped out by a kindly doctor who explains they've got a chemical imbalance and that medication will help."
+Healy is paid by the pharmaceutical company AstraZeneca to give talks on mental illness.
+Australian psychiatrists also concerned
+Chairperson of the Royal Australian and New Zealand College of Psychiatrists' Faculty of Child and Adolescent Psychiatry, Dr Phill Brock, is also concerned about children being inappropriately diagnosed with bipolar.
+"We do not endorse that diagnosis in children," he says.
+Brock runs the inpatient service of the Women's and Children's Hospital in Adelaide and says he is aware the diagnosis is being made, both by GPs and psychiatrists.
+"We would contend that because of the developmental context we're not able to say categorically that this is an illness that can be applied to children."
+He says he is aware of advocates for diagnosing bipolar in children and found it alarming when a US organisation approached the faculty he represents 18 months ago to set up a support group for infants and children with bipolar disorder.
+Healy says while a child might be hard to handle because they've moved house or school, because they've been bullied at day-care or because their parents aren't getting on it is "easier to locate to the problem in the child".
+Brock is similarly concerned.
+"We know that children and teenagers frequently have changes in mood. That's part of growing up," he says.
+For more information on bipolar disorder, including fact sheets and referrals, see beyondblue, Australia's national depression initiative.
+
+More than half of the authors of the DSM, the manual used to diagnose mental health problems, have had ties with the pharmaceutical industry. But not everyone agrees this is a bad thing
+Most of the experts who wrote the manual widely used to diagnose mental illness have had financial ties to drug makers such as research funding or stock holdings, US researchers report.
+They call for full disclosure of the relationships between companies and the medical experts on panels that craft future editions of the Diagnostic and Statistical Manual of Mental Disorders, known as the DSM. 
+"Transparency is especially important when there are multiple and continuous financial relationships between panel members and the pharmaceutical industry, because of the greater likelihood that the drug industry may be exerting an undue influence," the researchers write in a study to be published in the journal Psychotherapy and Psychosomatics.
+The American Psychiatric Association, which publishes the DSM, says it will require financial disclosures for the next version, due out in 2011.
+The study found 56% of 170 psychiatric experts who worked on the most recent edition, published in 1994, had at least one financial link to a drug maker at some point from 1989 through 2004. 
+The relationships included speaking or consulting fees, ownership of company stock, payment for gifts and travel and funding for research. 
+All the experts who developed sections defining mood disorders, schizophrenia and other psychotic disorders had such links, the study says. 
+"The connections are especially strong in those diagnostic areas where drugs are the first line of treatment for mental disorders," the study says. 
+Critics say psychiatric drugs are overprescribed. 
+Drug company links fruitful, say some
+Dr Darrel Regier, director of the American Psychiatric Association's research division, says the study is "an attempt to develop probably some guilt by association with the pharmaceutical industry". 
+He says he does not believe financial connections to companies influenced development of the manual.
+If none of the experts were involved with the industry, "that would mean they were really out of step with the major advances in the treatment of mental illness", he says. 
+The authors of the new study, researchers from the University of Massachusetts and Tufts University, say they based their findings on searches of various databases, financial disclosures in medical journals and other records. 
+They say they could not determine if the experts had ties to the companies while they were working on the manual.
+After the update
+But Dr Lisa Cosgrove, one of the study's authors, says the associations could raise questions even if they occurred after the experts update the DSM. 
+"They can certainly leverage their participation on the DSM, which is very prestigious, into lucrative consulting contracts," says Cosgrove, a clinical psychologist at the University of Massachusetts in Boston. 
+A spokesperson for the Pharmaceutical Research and Manufacturers of America, says the industry group has not yet reviewed the study.
+"But it is important to note that the physicians and other health care professionals who sit on expert medical advisory panels have impeccable integrity and base their decisions on independent judgments and research," he says.
+
+The weight of a saddle and rider can cause a horse's back to extend and in extreme cases cause vertebrae to grow together
+When a horse bears the weight of a rider it adjusts the position of its back and alters its limb movements, which could contribute to back pain and injury, researchers say.
+The finding adds to a growing body of evidence that horses used for recreation or sport are at risk of health problems.
+Many scientists, such as Patricia de Cocq, who led the recent study, hope the findings will improve future conditions for horses. 
+"The goal of this study is to advise horse trainers and saddle fitters on how to prevent injuries," says de Cocq, a researcher in the Experimental Zoology Group at Wageningen University in the Netherlands. 
+For the study, de Cocq placed special infrared light reflective markers on horses that were on treadmills.
+Infrared cameras used the reflected light to generate 3D images that focused on horse back vertebrae, joints and limbs as the animals walked with and without loads.
+The maximum total weight was about 75 kilograms. 
+She found that while all weight caused a horse to adjust its back position, the saddle with a rider led to the greatest adjustment. 
+"During walk, trot and canter, the position of the [horse's] back is more extended in the situation with a saddle and weight," de Cocq says.
+"Although the back is more extended during the complete stride cycle, total movement, expressed as range of motion, stays the same."
+The findings were presented at the Society for Experimental Biology's annual meeting in England earlier this month. 
+Kissing spines, and other ailments
+The back extension, according to de Cocq, is consistent with probable causes for the condition of 'kissing spines', when loads and repeated undulations push parts of the horse's back close together. 
+This usually happens between the withers and the loin, or in the region that involves the 10th -18th vertebrae. In advanced cases, sometimes parts of the spine grow together.
+"It is thought that the process is only painful in [this] acute phase," she says. 
+Horses with longer backs are more likely to suffer from back problems associated with riding, probably because of uneven weight distribution, de Cocq says.
+It is possible that horses bred to bear heavy loads, such as Icelandic horses, may be less vulnerable, but she says she has not studied these horses yet. 
+On the racetrack
+Back problems are not the only risk to horses that carry human riders. 
+A recent Journal of the American Veterinary Medical Association study found that some racehorses experience haemorrhaging from the pulmonary artery into the bronchial tubes and windpipe during intense exercise. 
+The disorder is most commonly found in horses that lost races and trailed the winner by an average of about 4 metres. 
+Half of all thoroughbreds experience this problem, called exercise-induced pulmonary haemorrhage, according to lead author Kenneth Hinchcliff, a professor of veterinary clinical sciences at Ohio State University.
+He says a number of treatments, including drugs and herbal products, are often administered before racing, but it is not clear if they always work. 
+For horse riders, de Cocq offered this advice: "Riders should pay attention to the signals a horse can give. For example, 'cold back' [when a horse stiffens its back or negatively reacts after bearing weight], problems with saddling, girthing and mounting the horse may be an indication that there are problems with the saddle or the riding technique."
+
+Electromagnetic radiation from mobile phones may affect how fast you brake or turn while driving
+Electromagnetic radiation from your mobile phone may impair your ability to make snap decisions, say when driving a car, an Australian study shows.
+The study, which will be published in the journal Neuropsychologia, found evidence of slowed reactions, on both simple reactions and more complex reactions, such as choosing a response when there is more than one alternative.
+The researchers found these effects after people were exposed to electromagnetic radiation equivalent to spending 30 minutes on the phone.
+Lead researcher Professor Con Stough, director of the Brain Sciences Institute at Swinburne University of Technology in Melbourne, says the reactions tested experimentally have real-life equivalents, such as making braking decisions when driving a car. 
+"If you are driving a car and somebody runs out in front you, your simple reaction time is the time it takes to brake, while your choice reaction time could be the time it takes to decide between braking, turning left, turning right or hooting the horn to avoid the collision," he says. 
+The study's 120 volunteers received either active or 'sham' radiation emissions for 30 minutes before swapping for a further 30 minutes. This meant a total active exposure of 30 minutes, equivalent to a long phone call.
+The researchers then tested the study participant's reaction times and memory using a battery of neuropsychological tests.
+As well as the effect on reactions times, the study found that radiation from mobile phones seems to improve working memory, used for example when remembering a phone number long enough to dial it.
+But Stough says this memory finding should be interpreted with caution because the underlying biological mechanism is not known.
+A small effect
+Stough emphasises that while the study raises the possibility that short-term exposure of mobile phone emissions affect brain activity, the effect is small. 
+"Further investigations such as functional magnetic resonance imaging are needed to confirm the neuropsychological changes associated with mobile phone emissions," he says.
+"Whether the results will affect the way in which people make decisions about using mobile phones I don't know. Mobile phones are such a part of how we operate these days that it is unlikely." 
+Researchers are still debating about whether mobile phones have a carcinogenic effect. But the World Health Organization says there is insufficient evidence to support this argument and studies are ongoing.
+Sleep studies, however, lend support that mobile phone emissions alter brain activity.
+Recent findings show that that electromagnetic radiation received after making a mobile phone call stimulates the brain during the early stages of sleep.
+
+Erosion can affect the rate at which mountains in New Zealand grow, says a researcher
+Mountains eroded by the wind and rain can actually grow larger, according to a Canadian geophysicist.
+Associate Professor Russell Pysklywec of the University of Toronto says he is the first to predict that events on the Earth's surface can affect geological processes hundreds of kilometres below.
+Pysklywec publishes his research on how erosion affects the way tectonic plates collide to form mountains in the current issue of the journal Geology.
+Mountains form in a number of ways, including subduction, when two plates collide and the edge of one plate slides under the other, pushing up the crust in the process.
+Eventually these mountains "clog up" the subduction zone, Pysklywec says, and change the way the plates collide so the subduction zone shifts elsewhere.
+Over time, the original mountains start to erode as new mountains form elsewhere in the new subduction zone.
+But when wind and rain wash away the material pushed up at the subduction zone, Pysklywec says the subduction zone does not get clogged up and this makes it easier for the mountains to keep growing there.
+He says this is a paradox. After all, you'd expect erosion to wear down mountains, not build them up. 
+He says the rate of erosion is critical.
+"Erosion doesn't really lower mountains very much because typically the erosion occurs at the same rate or less than the rate of plate convergence," says Pysklywec, who has developed a computer model to simulate what happens.
+Natural laboratory
+Pysklywec studied the Southern Alps of New Zealand, which have been forming with the collision of the Pacific and Australian plates, a process that began 5 million years ago.
+He says these mountains are the perfect "natural laboratory" for studying mountain-building because they are relatively young, which makes it easier to decipher the geological processes that are going on.
+But, Pysklywec says, his findings apply to any area of the world where plates  collide and mountains form.
+He says the effect of erosion on deep earth processes has been ignored because it is hard to imagine how erosion, which typically removes 1 centimetre of surface soil per year can affect 100-kilometre-thick tectonic plates.
+"But you have to multiply that by 5 million years," he says. "And all of a sudden it's not 1 centimetre of material, it's tens of kilometres of material that you're taking away."
+A hot topic in tectonics
+Australian geophysicist, Dr Wouter Schellart of the Australian National University in Canberra says researchers have been studying the effect of erosion on tectonic processes. But geologists are debating what effect it has.
+Previous research has focused on the first 30 kilometres of the Earth's crust, he says. But Pysklywec's research shows erosion can impact processes deep down as far as a few hundred kilometres.
+Yet Schellart wonders whether this latest research applies to mountains other than those in New Zealand.
+And he says the model doesn't account for where eroded sediment is deposited.
+"In real life it's normally deposited right in front of the mountain belt," he says, adding that this will push both plates downwards.
+He also says the rocks making up the Earth's crust in Pysklywec's model are weaker than they should be, which potentially overestimates the effect of erosion.
+
+GM cotton fights back against the Helicoverpa armigera caterpillar. But this transgenic cotton has its drawbacks, say some scientists (see Related Stories below)
+Research that led to genetically modified cotton, Australia's first transgenic broadacre crop, has been awarded a prestigious award.
+Three CSIRO scientists were last night presented with an ATSE Clunies Ross Award for their work on Bt cotton.
+They were among researchers in the fields of environmental science, metallurgy, information technology and physics to be presented with an award, in recognition of their "outstanding achievements in the application of science and technology for the social and economic benefit of Australia".
+CSIRO's plant molecular biologist Dr Danny Llewellyn, plant breeder and agronomist Dr Greg Constable and entomologist Dr Gary Fitt were awarded jointly for their work in combating the moth Helicoverpa armigera, the most destructive pest to broadacre crops.
+CSIRO licensed a gene from US biotechnology company Monsanto that produced a toxin from the bacteria Bacillus thuringiensis or Bt. The researchers then introduced the gene into Australian cotton plants.
+When the H. armigera caterpillar eats the transgenic cotton plant, the toxin attaches to its gut and poisons it.
+This alternative approach to pest management has reduced the use of chemical pesticides by 90%, saving farmers about A$180 million a year on spraying, the researcher say.
+"It used to cost A$200 million annually to spray cotton crops with pesticide to control the moth but now they only use about 10% of the insecticide they used to use," says Constable, the team leader.
+"The main issue was insecticide could contaminate land, air and water so this is safer for the environment and everyone as it only kills the moth, without harming other helpful insects, creatures or humans."
+Other award winners were:
+* Environmental scientist Dean Cameron from Biolytix Technologies in Brisbane for developing a waste treatment system that uses worms, beetles and microscopic organisms to recycle sewage and household waste into safe irrigation water and compost.
+* Professor Ron Sacks-Davis from Melbourne information technology company InQuirion, which creates information retrieval and text database management programs that searches tens of millions of pages per second. The programs have been used by US and Australian intelligence agencies for antiterrorism purposes and for drafting legislation
+* Perth metallurgist Dr Gerald Roach from Alcoa World Alumna for reducing the cost of alumina production, environmental impacts and energy use and improving product quality. His research improving ore extraction efficiency has reduced bauxite waste by hundreds of thousands of tonnes annually.
+* A lifetime achievement award was presented to Perth physicist Emeritus Professor Dr John de Laeter, AO, whose career began as a high school teacher. He was instrumental in developing five research centres in Western Australia, and in raising A$28 million for the scientific community and research.
+Former Clunies Ross award winner, joint winner of the 2005 Nobel Prize in Physiology or Medicine Professor Barry Marshall, who discovered that the bacteria Helicobacter pylori, rather than stress, causes stomach ulcers, was guest speaker at the awards ceremony.
+
+Choosing the racy red shoes over the sensible loafers relates to how your brain assigns values to items or goods
+Can't choose between the racy red shoes and the sensible loafers? 
+Scientists say this indecisiveness relates to how your brain cells assign values to different items.
+Researchers at Harvard Medical School in Boston have identified neurones that seem to play a role in how a person selects different items or goods.
+Scientists have known that cells in different parts of the brain react to attributes such as colour, taste or quantity.
+Now Dr Camillo Padaoa-Schioppa and Associate Professor John Assad describe in the journal Nature how neurones involved in assigning values help people to make choices.
+"The neurones we have identified encode the value individuals assign to the available items when they make choices based on subjective preferences, a behaviour called economic choice," Padoa-Schioppa says. 
+The scientists say this research is part of the emerging field of neuroeconomics.
+The scientists located the neurones in an area of the brain known as the orbitofrontal cortex (OFC) while studying macaque monkeys that had to choose between different flavours and quantities of juices. 
+They correlated the animals' choices with the activity of neurones in the OFC with the valued assigned to the different types of juices. 
+Some neurones would be highly active when the monkeys selected three drops of grape juice, for example, or 10 drops of apple juice. 
+Other neurones encoded the value of only the orange juice or grape juice. 
+"The monkey's choice may be based on the activity of these neurones," says Padoa-Schioppa. 
+Earlier research involving the OFC showed that lesions in the area seem to have an association with eating disorders, compulsive gambling and unusual social behaviour. 
+The new findings show an association between the activity of the OFC and the mental valuation process underlying choice behaviour, according to the scientists.
+"A concrete possibility is that various choice deficits may result from an impaired or dysfunctional activity of this population [of neurones], though this hypothesis remains to be tested," says Padoa-Schioppa.
+
+They're in here somewhere
+Researchers have made a new kind of fabric bag that can detect its contents and alert the owner when something is missing.
+The Ladybag, aimed at young professional women, could put an end to leaving the house without the mobile phone, house keys or wallet.
+"We are a group of six women on the team. We came up with the bag idea because we thought that all of us would use it," says team member Ginny Mesina, a student from Canada's Simon Fraser University. 
+Mesina and the team developed the idea as part of a course project, which placed students from the university's interactive arts degree and the information technology degree together. 
+To design the bag, the students used off-the-shelf technology.
+They embedded a radio frequency identification (RFID) reader, which is powered by a 9 volt  battery, into the bottom of the bag.
+They then wired the reader to a screen-like panel in the front of the bag, which contains three patterns of light-emitting diodes. 
+Each pattern is an icon representing an essential item that the owner does not want to leave home without. In the prototype, these items are a set of keys, a wallet, and a mobile phone. 
+They then attached an RFID sensor to each of those items. 
+As long as each item is missing from the Ladybag, its corresponding icon lights up. As the keys, phone, and wallet are each placed into the bag, the icon blinks off. 
+"I always forget my phone, but always remember my handbag. This is a great solution," says industrial designer Rosanna Kilfedder, a master's degree candidate at Scotlands Heriot-Watt University in Edinburgh. 
+Kilfedder designed the Suntrap Handbag, a solar-powered bag that absorbs sunlight by day and then lights up when it's dark to help search for items inside. 
+"I believe because people have seen how technology can make their everyday lives easier, they now want more traditional products updated to offer the same benefits," says Kilfedder. 
+And for their younger sisters
+The Ladybag team aims their product at 20-something women, but another version is designed to appeal to the preteen and teenager. 
+That Ladybag is equipped with a light-emitting diode screen that contains seven different expressive face patterns. 
+Five sensors located in different areas on the bag pick up various force and motion generated by the bag's owner and then translate that into one of the seven different light patterns. 
+For example, if the person fiddles frantically with the bag, the face with a worried look will light up. If the owner hugs the bag, a happy face emoticon will light up. 
+According to Mesina, the team has had a wave of unexpected attention and will be talking with the university's technology transfer department about patenting the Ladybag.
+
+Andy Roddick has the world's fastest serve at 240 kilometres an hour but the sky's the limit. Researchers say physics doesn't set an upper limit for service speed
+You can reduce the number of stupid mistakes you make on the tennis court by applying the laws of physics, a US researcher says.
+Professor Howard Brody of the University of Pennsylvania shows knowledge of the laws of matter and motion can lift your game in one of three main ways.
+It can cut errors of latitude (hitting the ball wide), depth (hitting the net) and force (hitting the ball too hard), says Brody in the current issue of the British Journal of Sports Medicine.
+Ball angle
+Brody says you can reduce the risk of the ball going wide by not changing the angle when returning a shot.
+"Changing the ball angle by attempting to return a cross-court shot down the line, or returning a down-the-line shot cross court is asking for lateral problems," he says.
+But this doesn't mean you have to return the ball where it came from every time, he says.
+If a player chooses to change the ball angle, the margin for error can be reduced by hitting the ball harder.
+Graphs charting ball angle relative to force show the ball leaves the racquet at a larger angle if the swing is slow, Brody says.
+"The ... statement that the angle of reflection equals the angle of incidence holds for light reflecting from a plane mirror, but not for tennis balls rebounding from a racquet," he says.
+Clearing the net
+A good groundstroke needs to clear the net while landing in the right place on the other side.
+And there is a maximum and minimal ball angle that allows this to happen.
+Using the laws of physics, a good stroke will therefore have an optimum vertical angular acceptance, which is maximum angle versus minimum angle, Brody says.
+Computer analysis shows that the harder you hit the ball, the smaller the angular window of acceptance.
+As ball speed increases from 80 to 96 kilometres an hour the acceptance window shrinks by 43%. The window increases as ball speed decreases.
+In other words, don't hit the ball too hard if you want to get it over the net.
+But this leaves players in a bind. Should they go for a fast shot, which is harder to hit but more prone to error, or a slower shot, which is likely to be more accurate but easier to return?
+"The player is fighting against both geometry and Sir Isaac Newton, as well as the opponent!" Brody says.
+Brody says adding spin to a fast shot can open the angular window of acceptance, because the spin acts like a downward, or Magnus force, helping gravity pull the ball onto the court.
+He says physics can also be applied to improving your serve and in identifying so-called sweet spots on the racquet that will achieve minimum vibration, minimum shock and maximum ball rebound speed.
+Putting it into practice
+Australian Associate Professor of physics Rod Cross of the University of Sydney has written a book on the science of tennis with Brody.
+He says physics can more accurately describe what happens when a player hits a ball than the player is aware of.
+"The idea is that a physicist can tell a coach what the player's supposed to be doing and why, and the coach can translate that to a player," he says.
+"I tried it myself. I phoned up [professional tennis player] Jelena Dokic and told her she wasn't serving properly.
+"She didn't hang up straight away."
+
+This composite image shows a vast cloud of hot gas (red), surrounding high-energy bubbles 10,000 light years across (blue) on either side of the bright white area around the supermassive black hole
+Black holes, the monstrous matter-sucking drains in space, are the most fuel-efficient engines in the universe, researchers say.
+Just how efficient? If a car could use this kind of engine, it could theoretically go about 1.6 billion kilometres on 4.5 litres of petrol, says Dr Steve Allen, an assistant professor at Stanford University.
+Unfortunately, no earthly car could do this, as black holes are fuelled by matter lured by the holes' vast gravity. Their pull is so strong that nothing, not even light, can escape. 
+Most of the energy released by this matter as it gets close to the black hole's point of no return, or event horizon, shows up in the form of high-energy jets, which spew forth from magnetised discs of gas. 
+These jets speed away from the black hole at speeds up to 95% of the speed of light, which is 300,000 kilometres per second, and create huge bubbles in the hot cosmic gas of the galaxies.
+These bubbles can measure hundreds or even thousands of light-years across. A light-year is about 10 trillion kilometres, the distance light travels in a year.
+To come up with their fuel-efficiency estimate, Allen and his colleagues used NASA's orbiting Chandra X-Ray Observatory to peer into the inner regions of nine giant elliptical galaxies.
+This view gave the scientists an idea of how much matter, the black holes' fuel, was available. 
+Other Chandra observations were used to figure out how much power would be required for the jets to produce the big bubbles.
+The scientists calculated that the energy in the jets is equivalent to about trillion trillion trillion watts. 
+The fuel reservoirs for these high-efficiency black hole engines are so big, the scientists say, they could keep things going for hundreds of billions of years.
+This is many times the current estimated age of the universe, which is 13.7 billion years. 
+How about other galaxies?
+This fuel-efficient phenomenon may be common to giant galaxies like the ones the researchers observed, which are about 10 times as massive as ours. 
+But they are probably not common to the Milky Way, the scientists say.
+Dr Kim Weaver of NASA's Goddard Space Flight Center says these supermassive black holes also appear to limit star formation and galactic sprawl.
+The heat coming from the black hole jets is believed to heat up the gas around the galactic centre. Without this source of heat, the gas would cool down and form new stars, Weaver says.
+"This is one way to keep the stars from forming and letting the galaxies grow bigger," she says.
+
+The UK's mainstream power providers have caught onto wind power, technology they once dismissed
+Environmental activists are driving commercial innovation and seeding new mainstream industries, a UK study says.
+University of Sussex researchers carried out the study for the UK's Economic and Social Research Council.
+The study says rather than putting up hurdles to economic progress, radical activist groups and proponents of a greener lifestyle are driving developments in mainstream businesses like wind energy, organic food and eco-housing.
+"Activists often struggle to keep projects going and fail to produce the radical transformations they originally envisaged," says author Dr Adrian Smith.
+"This lack of breakthrough inclines them (and others) to underestimate the effect of their ideas.
+"But we found that although their influence is more subtle and beyond their control, it is still hugely significant in many cases."
+Australian sustainability pioneer and engineering lecturer at the University of Technology Sydney, Michael Mobbs, says the report rings true for him.
+The environmental lawyer was renovating his Sydney home in 1996 when he decided to put in sustainable features, including a water tank, a reused sewage system and solar panels.
+At the time people thought he was "frothing at the mouth or somehow abnormal", he says.
+Ten years later, 17,000 people have toured his home and he advises policy makers, developers, builders, architects, engineers and "mainstream, middle class Australians".
+"There are now laws requiring rain tanks and many of the things I did that were regarded as weird and stupid are now in red tape," he says.
+"The engineers who were once critical of me are now describing themselves as sustainability experts."
+Mobbs is currently helping Western Australia's Department for Planning and Infrastructure design a sustainable village at Gracetown.
+Tamra Lysaght is the managing director of Australia's National Invention Centre, which helps innovators commercialise their ideas.
+Australia may be lagging behind Europe in taking up the ideas of fringe groups because she says Australia's environmental problems aren't as pressing and there's less government support for sustainable projects.
+She says while the centre doesn't usually deal directly with activists, aspiring inventors often put an environmental spin their product as a "selling point".
+Lysaght says no one single group can be credited with driving change and a move to more sustainable industries is a response to a network of social and economic factors.
+She also says environmental activist groups can sometimes be an impediment to the development of potentially beneficial technologies, such as nuclear power.
+"The environmental movement has certainly been a key player in curtailing the nuclear power industry in Australia and globally," she says.
+"But whether you view that as good or bad depends on which side of the fence you're sitting on."
+The report Supporting and Harnessing Diversity? Experiments in Appropriate Technology can be downloaded from the research council's website.
+
+Leo the Lion and his 11 other signs of the zodiac don't define your personality, a new study shows
+One of the largest studies of the possible link between human traits and astrology has found little, if any, connection between the traditional Sun signs of the zodiac and people's characteristics. 
+The study adds to the growing body of evidence that there is no scientific basis for star signs, like Aries and Taurus, signs that are based on the place of the Sun in relation to someone's date of birth. 
+But the researchers leave open the question as to whether other, more detailed and personal forms of astrology hold any validity.
+"When considering the current scientific standing with respect to Sun signs, it becomes clear that there is little or no truth in [them]," says Dr Peter Hartmann, who led the study in the May issue of the journal Personality and Individual Differences.
+"This does not necessarily mean that all astrology is without truth, but only that the independent effect of Sun signs is most likely to be irrelevant," says Hartmann, a researcher in the Department of Psychology at Denmark's University of Aarhus.
+"As for the weekly horoscope based on mere Sun signs, then according to the current scientific standing, there is probably more truth in the comic strips." 
+Hartmann and his colleagues used computer analysis and statistical methods to study possible astrological connections between over 15,000 individuals. Their test subjects came from two sources. 
+The first was the Vietnam Experience Study, which gathered information about intelligence, personality and date of birth for male military veterans.
+The second was the 1979 National Longitudinal Study of Youth, which included intelligence and date of birth information for males and females aged between 15 and 24 years. 
+If connections existed over a rate of 5%, they were considered valid and not the result of random links. 
+No link in Vietnam
+The scientists could find no relationship between the time and date of a person's birth and their personality traits, which the Vietnam study categorised using terms such as psychoticism, extraversion, neuroticism and social desirability. 
+The researchers, however, did determine that individuals from the Vietnam test who were born between the months of July and December were slightly more intelligent, by less than one IQ point, than those who were born between January to June. 
+That finding was reversed for the 1979 youth study. In that case, people who were born January to June had the minute intellectual edge. 
+And in the real world?
+Hartmann says that although the information about intelligence passed the non-random restriction, he views the connection as irrelevant. 
+"Assuming that you could buy a pill that would increase your IQ with one point, but it would cost you $10,000, would you do it? Probably not, but if you could buy a pill that would increase your IQ by 15 points that would be something else, simply because you get more value for your money," he says. 
+"The essence here is that there is a difference in determining whether a result is significant, hence whether it is a true effect, or just random occurrence, and then whether this significant effect is relevant and of any interest." 
+The Australian connection
+Geoffrey Dean, a former astrologist based in Australia who researches the possible scientific validity of astrology, tracked over 2000 people who were born within minutes of each other. 
+The study, which spanned several decades, covered over 100 different characteristics, like marital status, IQ, anxiety and temperament was published in 2003 in the Journal of Consciousness Studies.
+Dean came to a similar conclusion as Hartmann and his team, that date of birth does not affect an individual's personality.
+
+There's no motivation to put up Arabic content on the web as there's no dedicated search engine to find it, commentators say. But that may be about to change with the launch of a new search engine later this year
+Plans for a dedicated Arabic language search engine could boost the number of Arabic webpages, its developers say.
+The Saudi-German search engine, called Sawafi, is planned to be launched in the last quarter of 2006.
+And it could set a tough challenge for international search giants such as Google, MSN and Yahoo, which currently offer a basic Arabic search. 
+"There is no [full] Arabic internet search engine on the market. You find so-called search engines, but they involve a directory search, not a local search," says Hermann Havermann, managing director of German internet tech firm Seekport.
+Sawafi, working with Saudi partner Integrated Technical Solutions, is hoping to copy the success of local Chinese language search engine Baidu, which has made huge strides in a market with over 100 million users.
+Everything is to play for in the Arabic speaking world of 280 million people, where internet penetration is low. There are also large communities Arabic speakers internationally.
+"There are only 100 million webpages right now in Arabic, and that's nothing. It's only 0.2% of the total worldwide," Havermann says. 
+Research commissioned from Dubai-based Internet researcher Madar shows the number of Arabic speaking internet users could jump to 43 million in 2008 from 16 million in 2004, Havermann says.
+According to Madar, 65% of Arabic internet users in 2005 could not read English, which accounts for 70% of the material on the internet. 
+Better search engines are key to a turnaround. 
+"There is not enough Arabic content available on the internet. But there's no motivation to put more Arabic content on the internet as long as you don't have a system to find the content," Havermann says. 
+Saudi Arabia, with an affluent population of 24 million, and Dubai in the United Arab Emirates would be key places for winning online advertising to fuel Arabic search engines. 
+"Search engines are dependent on income from advertising, and for this you need partners and marketing agencies. They are in Dubai," Havermann says. "On the other side, the Arabic user market is in Saudi Arabia."
+
+Microbiologists have found the bacteria resonsible for preparing fart-free beans
+Beans cooked with a pinch of bacteria means diners can tuck in without the explosive results, scientists say.
+Researchers from Venezuela say two strains of bacteria are the key to producing fart-free beans.
+They show how Lactobacillus casei and Lactobacillus plantarum can be added to beans so they cause minimal distress to those who eat them, and to those around them.
+Marisela Granito of Simon Bolivar University in Caracas and colleagues report their results in the Journal of the Science of Food and Agriculture.
+Flatulence is caused by bacteria that live in the large intestine that break down food not already digested higher in the gut. The gas the bacteria produce is emitted from the body as a fart.
+Granito and colleagues found that adding these two gut bacteria to black beans, or Phaseolus vulgaris, before cooking makes them even less likely to cause flatulence.
+"Legumes, and particularly Phaseolus vulgaris, are an important source of nutrients, especially in developing countries," Granito's team writes.
+"In spite of being part of the staple diets of these populations, their consumption is limited by the flatulence they produce." 
+Smart cooks know they can ferment beans, and make them less gas-inducing, by cooking them in the juices from a previous batch.
+But Granito's team wanted to find out just which bacteria were responsible.
+Cooking up a storm
+When the researchers fermented black beans with the two bacteria, they found it decreased the soluble fibre content by more than 60% and lowered levels of raffinose, a compound known to cause gas, by 88%. 
+They fed the beans to rats and then analysed the rats' droppings to ensure that the beans were digested and kept their nutritional value. 
+When pre-soaked in L. casei, the beans stayed nutritious and produced few gas-causing compounds, the researchers report. 
+"Therefore, the lactic acid bacteria involved in the bean fermentation, which include L. casei as a probiotic, could be used as functional starter cultures in the food industry," the researchers write. 
+"Likewise, the cooking applied after induced fermentation produced an additional diminution of the compounds related to flatulence."
+
+Space explorers have been urged to consider the implications of exploring the cosmos before taking another leap for mankind
+We will need an intergalactic police force to keep order in space and protect the interests of the vulnerable, says a US ethicist.
+Dr Patrick Lin, of the The Nanoethics Group in Santa Barbara, California, says we should be thinking about the ethical implications of future space exploration. And some kind of government or police force should be considered.
+He will tell the International Space Development Conference in Los Angeles next week that it is not clear that an Earth-based government would be the most effective.
+"Space has been long called 'the final frontier', but have we taken the time to consider what our responsibilities are as 'frontiersmen'?" says Lin.
+Lin's recommendations are part of a call for space explorers to look before taking another leap for mankind.
+Commercial space travel is becoming a reality, he says, and the public needs confidence that governments, scientists and astronauts are considering the consequences of exploring space.
+For instance, Lin says we need a fair process for commercialising or claiming property in space to avoid what he calls the kind of "chaotic land-grab" that occurred with internet domain names.
+"We would not rush to develop the south pole without a well-thought plan, so the same reasonable precaution would seem to apply to colonising space," he says.
+There he says there are legal disputes already.
+Despite UN treaties declaring space as commonly-owned, he says lawsuits have been filed to lay claim to asteroids.
+Why are we doing it anyway?
+Lin says it is important to have a justifiable reason for exploring space.
+"Are reasons such as for adventure, wanderlust or 'backing up the biosphere' good enough to justify our exploration of space?"
+He says we should question the idea that space may provide an escape for us if our world becomes overpopulated and uninhabitable.
+"Does having a safety net, such as a back-up planet, make it more likely that we take more chances and treat our current planet less carefully?"
+Lin says issues such as polluting space, the proliferation of military technologies in space and the safety of space travellers should also be considered.
+"We have already littered our outer atmosphere with floating space debris that rockets and satellites need to track and navigate around, not to mention abandoned equipment on the Moon and other planets," he says.
+"Have we learned enough about ourselves and our history to avoid the same mistakes as we have made on Earth?"
+Finally, says Lin, some critics suggest it may be better to spend money on alleviating poverty and hunger, providing access to clean and affordable water and energy, and addressing other issues including human rights violations.
+Plenty of real estate in space
+Australian cosmologist and space exploration advocate, Professor Paul Davies, agrees space exploration is a "free for all" but doesn't think regulation is needed.
+He says he supports the views of US physicist and futurologist Emeritus Professor Freeman Dyson, of the Institute of Advanced Studies in Princeton, who sees space as "an escape from the straightjacket of an over-regulated Earth".
+"We could find whole new ways of organising society," says Davies of the Australian Centre for Astrobiology at Macquarie University in Sydney.
+Davies says space is not finite in the same way Earth is, which means there is less need to control development there.
+"In a sense, space is unlimited," he says. "There's a lot of real estate out there and no possibility I think within a thousand years of any sort of territorial conflict."
+But Davies believes we should be regulating exploration of Mars, if we find life there, to ensure scientists can study it.
+He also says we need to take the issues of space junk and militarisation of space seriously.
+But he does not think it's fair to say money spent on space exploration should be spent on solving problems on Earth.
+"Let's stop sport and spend that money on alleviating poverty in Africa," he says. "You never hear that argument."
+
+Gravity and not colliding space rocks made Neptune and the other giant planets tilt, according to a new hypothesis
+An early gravitational dance made the giant planets tilt, an astronomer suggests.
+The shift probably happened billions of years ago when the bigger planets in our solar system were closer together than they are now, and the gravity of each one pulled on the others, writes Argentinian researcher Dr Adrian Brunini today in the journal Nature.
+This "neutral gravitational interaction" caused Jupiter, Saturn, Uranus and Neptune to have tilted axes that were determined as they moved through the solar system to take their current positions far from the Sun, says Brunini, from the Facultad de Ciencias Astronomicas y Geofisicas in Buenos Aires.
+This is a departure from an earlier theory that holds that the massive planets' tilts, or obliquities, were caused by collisions with Earth-sized space rocks during the early period of the solar system. 
+"This model has some problems that were not clear how to solve," Brunini says. "For example, we believe that such a big object never existed in the outer solar system." 
+Gravity on gravity
+Brunini used numerical models to show that the outer planets' obliquities could have been created by gravitational interactions. 
+All the planets in our solar system have tilted axes but the bigger ones have axes that lean at a constant angle, while the smaller ones like Earth have obliquities that can change. 
+Despite the potential for change, Earth's axis has been leaning at about 23&deg; for millions of years and is almost completely stabilised by the Moon's gravitational pull, Brunini says.
+But Mars' axis might change over tens of millions of years. 
+Earth's tilt stable but crucial
+For humans, the reliability of Earth's tilted axis is important as it is responsible for the change of seasons. At the point in its annual orbit where Earth's northern hemisphere leans away from the Sun, it's winter; when the southern hemisphere tilts away, it's winter south of the equator.
+While the more massive planets have stable obliquities, they range in size from a nearly perpendicular 3&deg; for Jupiter to about 97&deg; for Uranus, Brunini says.
+
+It took an average of 3 to 4 months for men to regain their fertility after stopping the 'pill'. But some men had to wait as long as 2 years
+Worries that the male contraceptive 'pill' may wreck a man's chance of fathering a child are unfounded, says a new study.
+Men given a hormone-based contraceptive can regain their fertility about four months after stopping the treatment, researchers report today in The Lancet journal.
+Drug companies have been working on a male pill or injection to inhibit sperm production and give couples a greater choice of family planning methods. 
+The three main male contraceptive methods - the condom, withdrawal and vasectomy - are regarded by many as insufficiently reliable or difficult to reverse. 
+The male pill uses the hormone androgen, or a mixture of androgen and progestogen, to suppress sperm production to zero or negligible levels. 
+US and Australian scientists analysed studies involving men who had been given the contraceptives in trials and found the treatments were highly effective but reversible. 
+"Hormonal male contraceptive methods could soon become widely available," says Dr Peter Liu currently at the ANZAC Research Institute at the University of Sydney. 
+"These findings thereby increase the promise of new contraceptive drugs allowing men to share more fairly the satisfaction and burden of family planning."
+Large-scale trials of male hormone-based contraceptives are being conducted in China and Europe, the scientists say.
+Liu and his team analysed data on 1500 men who had taken part in 30 trials that had been published between 1990 and 2005. 
+All participants recovered fertility after they stopped taking the hormones. On average, it took 3.4 months to achieve this, defined as a threshold of 20 million sperm per millilitre.
+But some men took as long as two years to regain their fertility.
+The researchers say various factors, including age, original sperm count, duration of treatment and ethnic origin, could influence the recovery rate.    
+Two of the study authors are employed by pharmaceutical companies.
+
+The researchers compared the DNA from different types of banksia and other woody plants around the world
+Tropical plants evolve twice as quickly as their cousins from more temperate regions, researchers say. 
+That could provide the answer to one of the most puzzling questions about evolution - why there are so many more species in tropical regions than there are in temperate zones.
+A New Zealand study, published online today in the Proceedings of the National Academy of Sciences, measured the rate of change that had occurred over millions of years in the DNA of 45 closely paired species of woody plants.
+"For each pair we used two closely related species, one from the tropics and one from a temperate zone," says co-author Dr Len Gillman from Auckland University of Technology. 
+The study compared plants included conifers, kauri pine, grevilleas and wattle from tropical areas of Australia, Papua New Guinea and the Amazon with their counterparts in temperate zones in countries including New Zealand, the US and Australia's island state of Tasmania.
+By sequencing a particular region of DNA in each pair and comparing it to the same region in an equivalent common ancestor, the team were able to measure the rate of evolutionary change.
+"We found that there was double the molecular change in the tropical species," says Gillman.
+"If you've got twice the rate of evolution occurring you've got twice the opportunity for species to be generated and accumulate over time."
+The study suggests that the faster rate of evolutionary change in tropical plants is due to higher metabolic and productivity rates. A higher metabolic rate leads to more cell division and increases the opportunities for mutation. 
+Although it was suspected that more energy was responsible for the greater species diversity towards the equator, the New Zealand team is the first to demonstrate a mechanism - a faster rate of evolution.  
+The researchers say that this is unlikely to be caused by rapid genetic drift in the generally smaller populations of plants in the species-rich tropics, though it warrants further investigation.
+They suggest that the greater rate of speciation seen in the tropics is a consequence rather than a cause of the faster rate of molecular evolution.
+
+People have until 1 May to have their say in Australia's national nanotechnology strategy
+The Australian public is being left out of crucial decisions on nanotechnology that will affect their future health, environmental, social and economic wellbeing, says an environmental group.
+The Friends of the Earth (FOE) says the government taskforce charged with developing a national nanotechnology plan is treating public input as a "tokenistic add-on" rather than something that should help shape Australia's response to the technology.
+The government has given the public the month of April to make submissions to its nanotechnology strategy. But FOE says this is not enough.
+"Public awareness of nanotechnology is so low that this is a really inappropriate way for [the taskforce] to be seeking public involvement," says  Georgia Miller of FOE's nanotechnology project.
+FOE wants a public education campaign on nanotechnology, public meetings and consensus conferences or other processes to involve a broader range of the public.
+Miller says the process should be independently funded and run by a steering group of representatives from all parts of society likely to be affected by nanotechnology.
+"This isn't a radical suggestion," she says. "This is something along the lines of what the UK government has already set up to oversee its public engagement process on nanotechnology."
+Miller says unions, environmental, public health, farming, disability rights, consumer and civil liberties groups should be involved in developing the strategy. But she says the taskforce has had only "ad hoc" contact with groups other than those from science and industry.
+Discussion paper lacking
+The National Nanotechnology Strategy Taskforce, the body within the federal industry department charged with developing Australia's nanotechnology plan, issued a discussion paper for public comment.  
+But Miller says this discussion paper "trivialises" the potential risks of nanotechnology, which she says is already widely used unlabelled and untested in commercial products.
+She says bodies like the UK Royal Society have recommended nanomaterials be assessed as new products but the paper makes no mention of legislation to manage any risks.
+Miller also says the paper should have mentioned efforts by researchers to enhance humans, by combining nanotechnology with biotechnology, information technology and cognitive science.
+And she says it should have recognised the economic impact of nanomaterials.
+"Carbon nanofibres may displace cotton but this isn't even mentioned and this would have huge impacts for Australia," she says.
+Extensive consultation
+David Gallagher, general manager of the National Nanotechnology Strategy Taskforce, says surveys show there is a low level of public knowledge about nanotechnology but that is not surprising.
+He agrees the discussion document is limited, for example on health and safety issues, but says it was only designed to be a starting point for public comment.
+"The point of the public process is to determine if people believe health and safety is an issue, and if it is why," he says.
+A spokesperson for industry minister Ian Macfarlane says the taskforce is undertaking "extensive consultation" with industry, science and community groups to develop the strategy.
+"The government recognises that public engagement is not a 'one off' process," the spokesperson says. 
+"It is likely that options for a national nanotechnology strategy will place priority on the need for ongoing effective public engagement, awareness and debate - much in the same way as has been done with biotechnology."
+Balancing act
+Nanomaterials researcher Professor Chennupati Jagadish, who convenes of the Australian Research Council Nanotechnology Network and has also advised the taskforce, says public engagement is "absolutely essential".
+But he says it's a "balancing act" because Australia needs the national strategy so it can be competitive internationally.
+"Time is also of the essence," says Jagadish, who is based at the Australian National University in Canberra.
+Australian Council of Trade Unions occupational health and safety officer Steve Mullins says he sees the strategy discussion paper as the beginning of the process to raise public awareness about nanotechnology, not the end.
+"There is a very real risk that environmental and health and safety concerns will be sidelined by government and business in their enthusiasm to develop the industry in Australia," he says.
+The taskforce is due to report to the minister in June.
+
+Controversy over GM crops continue but a new report recommends no changes to the law
+Calls for changes to the laws governing gene technology in Australia have been largely rejected in a new report, despite ongoing controversy over genetically modified crops.
+A review of the Gene Technology Act 2000, by a government-appointed review panel, found there should only be minor changes to the Act, which it outlines in a report released this week.
+The review also calls for states to end their moratoria on genetically modified (GM) crops.
+"It was the issue that was raised at every forum - it was the hot issue," says review panel chair, environmental lawyer Susan Timbs.
+The review rejects calls for the Act to be changed so that economic, social and marketing impacts of GM crops could be considered.
+And it agrees with GM researchers and industry that GM and non-GM crops can co-exist.
+The review also disagrees with some farming and consumer groups, that people releasing GM organisms (GMOs) be made strictly liable for any detrimental effects of their products.
+More time to assess risky applications
+But the review recommends some changes in the way the Office of the Gene Technology Regulator (OGTR) assesses applications for the release of GMOs.
+The review recommends the regulator be given more time to assess applications for the commercial release of organisms deemed to be of "significant risk".
+Timbs says under the proposal this would provide more time for public consultation.
+But the time limit for assessing field trials would be reduced and industry and researchers conducting low risk work with GMOs would have less requirement to report their activities, Timbs says.
+The review also recommends the Gene Technology Technical Advisory Committee (GTTAC), which advises the OGTR on risks, should include people with specific expertise in public health and environmental risk assessment.
+Responses
+Senator Natasha Stott Despoja, Australian Democrats' spokesperson on science and biotechnology, says the review makes few recommendations to improve the system.
+"The report found a 'high level of transparency in relation to the regulatory system', which appears to be contradicted by the lack of information made available to the public on GM trials by the Office of the Gene Technology Regulator," she says.
+"The report also found the states' moratoria on GM crops to have 'detrimental rather than beneficial impacts (on markets)'. Given the evidence of GM contamination of non-GM crops, and the lack of research into the impact of human consumption of GM products, the states are showing an appropriate level of caution in regard to this technology."
+Professor Sue Serjeantson of the Australian Academy of Science says the Act has provided a climate of community confidence about GMO assessment.
+But she says the moratoria are a disincentive for research and means the Act has failed to "capture the benefits of biotechnology for the Australian community, industry and the environment".
+She says the moratoria may not be in place if the community had "access to quality information about biotechnology, the potential risks and benefits of its application".  
+"This highlights the necessity for the OGTR to be involved in increasing public awareness of GM technology, to assist the regulator applying the Act."
+
+NASA engineers have made minor tweaks to the design of Discovery's external fuel tank. But they are waiting until after the next launch to redesign small foam wedges of insulation
+The US space agency says it will not make any more changes to the design of the shuttle's fuel tank until after the next flight, despite ongoing concerns about foam insulation breaking off and damaging the shuttle during launch.
+NASA's shuttle program manager Wayne Hale acknowledged a slight risk that a small chunk of foam could break off from a newly exposed part of the external fuel tank and critically damage Discovery's heat shield during its proposed July launch. 
+The insulation prevents ice from building up and breaking off during launch. 
+Shuttle Columbia and its crew of seven astronauts were lost during atmospheric re-entry in February 2003, due to wing damage from a piece of foam insulation that fell off and hit the shuttle during launch. 
+The tank was redesigned, but foam from another part of the tank was lost during the first post-Columbia launch of Discovery last July. 
+Engineers then removed two aerodynamic ramps of foam that had protected a box of cables and two pressurisation lines from the tremendous winds and turbulence created by the shuttle's supersonic climb to orbit. 
+Hale says the ramps' removal was "the largest aerodynamic change that we have made since the shuttle first flew". 
+Tests to determine if the new design is safe to fly remain under way.
+After much debate, Hale decided making more than a major change in the tank's design was riskier than the slight chance of a critical impact by the small foam wedges. Those chunks cover metal brackets that attach the cable tray and pressurisation lines to the outside of the tank. 
+"We had to ask whether it's appropriate to make more than one change to the outer shell of the vehicle," Hale says. "If we go fly and have another accident that will be the end of the program." 
+Upon Discovery's safe return, engineers will redesign the small foam wedges, Hale adds. 
+NASA wants to fly the shuttle another 16 or 17 more times to complete construction of the International Space Station and possibly service the Hubble Space Telescope before the fleet is retired in 2010. 
+Managers expect to make a decision about whether the shuttle's redesigned tank is safe to fly at a review scheduled for mid-June. 
+NASA's next opportunity to fly a shuttle to the space station under its post-Columbia safety protocols, which include a daylight launch, is 1-19 July.
+
+You're more open to suggestion with a cup of coffee in your hand, research shows
+If you want to bring someone around to your way of thinking you should make sure they've got a cup of coffee in their hand, according to research showing that caffeine makes us more open to persuasion.
+The Australian researchers say a caffeine hit improves our ability to process information and increases the extent to which we listen to and take on board a persuasive message.
+They tested this by quizzing people about their attitudes to voluntary euthanasia and abortion before and after either the equivalent of about two cups of coffee or a placebo.
+They were also given a persuasive argument to read after having the caffeine.
+The experiments showed that "caffeine increases persuasion through instigating systematic processing of the message".
+But caffeine also puts people in a better mood, which makes them more likely to agree with a message, the researchers say.
+The research is posted on the Queensland University of Technology website and is submitted for publication in the European Journal of Social Psychology.
+What does this mean for advertising?
+Co-author Dr Blake McKimmie says the research suggests that caffeine increases our ability to scrutinise the content of a message.
+The study has implications for advertisers, he says, because it suggests that they should schedule adverts for times when people are likely to be consuming caffeine, such as breakfast time.
+Drinking too much coffee, however, means we're more likely to be distracted by peripheral factors, rather than the strength of the argument.
+"So if you're looking at an advertisement you may be more distracted by the attractiveness of the person selling it than the actual product," he says.
+Caffeine on the brain
+Associate Professor Pradeep Nathan of Monash University, an expert in behavioural neuroscience who was not involved in the research, says caffeine stimulates the central nervous system including the brain, where it affects several neurotransmitters.
+The Melbourne-based researcher says it improves memory and makes us pay closer attention to tasks at hand.
+"It does improve attention and it can improve memory so by being more attentive and remembering your attitude to a particular thing may change," he says.
+"If you're more attentive, yes [it does have implications for advertising]. Advertising works on the principle of getting people's attention, you want to get as many people interested in your ads as possible."
+But will it last?
+Geoff Kelly is the chief executive officer of an Australian consultancy that advises governments and corporations on how to get people to buy a particular message.
+He says there are different levels of persuasion and the key to success lies in whether the persuasion is long term.
+"Many things can be instrumental in persuasion but will they last in the long term?" he says.
+"If I have the magical technique to take you out to dinner it might work, but it doesn't mean I can get you to go out with me."
+
+Resting your forearms on a soft support as you type seems to reduce your chance of pain in the neck, shoulders, arm, wrist or hand
+Office workers who use a simple forearm support might avoid the pain that can come with long days at the computer, new research suggests.
+In a year-long study of 182 workers at a call centre, researchers found that those who received forearm supports for their desks were less likely to suffer pain in the neck, shoulders, arm, wrist or hand.
+They were also less likely to be diagnosed with a musculoskeletal injury in the neck or shoulders, according to findings published in the latest issue of the journal Occupational and Environmental Medicine. 
+The forearm support used in the study was a padded board that attaches to the front edge of workers' desks.
+The support is placed right under the "meaty part" of the forearm, positioning computer users' arms in a way that releases tension in the shoulder muscles, says lead author Professor David Rempel from the University of California, San Francisco.
+Based on these findings, employers should consider providing forearm supports to workers who spend substantial time in front of a computer, Rempel says.
+The results were less positive, though, for a trackball, a large ball installed next to the computer keyboard that takes the place of the mouse.
+While it did ease some workers' discomfort, others found it hard to use, Rempel says. 
+The study included employees at a large insurer's call centre, all of whom spend their workday at a computer.
+Some workers received a forearm support for their desks, while others received a trackball. 
+All employees were also given ergonomics training so they could learn how to make their entire workstation more comfortable. 
+Over the next year, Rempel's team found workers who used a forearm support were half as likely as those who received only ergonomics training to be diagnosed with a neck or shoulder injury.
+They also reported less pain in the neck, shoulders and right arm. 
+The cost of forearm supports is not negligible, Rempel says. But in a cost analysis, he and his colleagues found that the supports could be a worthwhile investment, considering the potential savings in medical and workers' compensation expenses. 
+"They would pay for themselves in about 10 months," Rempel says. 
+But forearm supports alone are not sufficient, according to the researchers.
+Rempel says all employees should receive proper safety and ergonomics training to reduce their chances of on-the-job injuries.
+
+Be careful what you write in your blog. The boss could be watching
+Bosses are considering putting specific provisions in employment contracts that could regulate what you put in your private blog or even prevent you from blogging at all, according to a new book.
+A chapter on blogging and the law, written by two Australian experts, says such clauses could stop employees from referring to their workplace even when they are writing personal blogs from their own home.
+"Employers are now considering including specific blogging provisions in employment contracts," the authors write in Uses of Blogs, a book to be published later this year.
+"Some employers have even taken the steps to ensure that employment contracts disallow employees from blogging at all."
+Co-author Damien O'Brien from the Queensland University of Technology law faculty says some workplaces have specific policies against blogging in the office but "it can get a bit blurred whether [it's] in the workplace or at home".
+"Certainly some of the provisions that would be put in contracts would cover when people are blogging outside their work," he says.
+The trend comes after a recent spate of cases in which employees have run into trouble over personal blogs, including a US flight attendant who was sacked for allegedly posting images of herself in uniform.
+The practice of sacking people because of their blog has even got a name, doocing, after a US woman who was allegedly dismissed for writing satirical accounts of her workplace in her private blog at dooce.com.
+Changing technology?
+Stephen Price is the workplace relations practice leader at the Australian law firm Corrs Chambers and Westgarth and advises a number of large corporations on workplace issues.
+He says concerns about blogging are related to issues like disclosure of confidential information or defamation of bosses, clients or colleagues, which originally focused on email.
+"As technology has moved on that concern has highlighted new areas and one of those new areas is blogging," he says. 
+Price says none of his clients has attempted to restrict employees blogging and he isn't aware of a blog-related case coming before an Australian court.
+"But in the future it wouldn't surprise me," he says.
+"It's pretty hard to draw up a contract that says you can't blog at home privately and have that upheld unless the person was distributing confidential information or defaming or harassing somebody, which would be covered by other provisions of the contract."
+Making policy clear
+Professor Brian Fitzgerald, head of law at Queensland University of Technology and a co-author of the chapter on blogging and the law, says as a so-called "disruptive technology", all parties may have to adapt to the fact that blogging is here to stay.
+"Yes the law will need to adapt, yes bloggers will need to adapt but also the big players will have to adapt," he says. 
+"The blogging issue is a bit like accessing websites, every workplace needs a protocol."
+Uses of Blogs, to be published by the Peter Lang Publishing Group in New York, is due for international release this year.
+
+Imaginary playmates are a sign of a rich fantasy life, but can also hint at problems, researchers say
+Children with imaginary friends have more vivid daydreams than other children, a new study shows for the first time.
+Australian researcher Dr Paula Bouldin of Deakin University shows that children with imaginary friends also tend to have more "mythical content" in their dreams.
+They spend more time daydreaming and have an ability to "almost ... see and hear the contents of their daydream in front of them".
+It may appear obvious that children with imaginary friends have a richer fantasy life than those without, but to date there has been little specific research into the area.
+Bouldin says her work, reported in the Journal of Genetic Psychology, finally provides evidence of this.
+She questioned 74 children aged between three and eight, half with a current or past imaginary friend.
+The group with imaginary friends reported more mythical content in their dreams, had more frequent and more vivid daydreams and were more likely to play games with a mythical content.
+When imaginary friends turn nasty
+Dr Louise Newman, a child psychiatrist and the director of the New South Wales Institute of Psychiatry, says the study confirms what has long been suspected.
+But she says further research needs to look at the psychological and emotional function of imaginary friends.
+Newman says while some imaginary friends function as sort of "super peers" or the "perfect playmate" they can also be a sign of emotional disturbance.
+"There are some cases in which children have those companions because they might be lonely, distressed or unable to put into words things that are concerning them," she says.
+"Some friends ... can be quite persecutory or frightening, they might torment the child, or express doubts, tell them they're stupid or bad."
+Newman says while imaginary friends are quite common in younger ages, they are more likely to be associated with emotional or family problems in children over the age of about seven.
+Adults with imaginary friends
+Most children grow out of imaginary friends, Newman says. But in some cases an imaginary friend can emerge in adulthood, usually in response to trauma, inability to cope with stress and sometimes psychotic illness.
+ In rare cases some adults develop what's known as Doppelganger syndrome, which occurs when they believe a twin or invisible friend accompanies them.
+"Other people believe in angels and guardian angels, and they don't think there's anything out of the ordinary about that," she says.
+Bouldin says her study suggests children with imaginary friends can readily access fantasy themes and may develop sophisticated information processing skills.
+But she says it could also be that children with imaginary friends are simply more willing to discuss their fantasies than those without.
+
+Genetically modified viruses that line up and conduct electricity could be the basis of a new generation of batteries
+Genetically manipulated viruses could replace standard lithium-ion batteries, packing two to three times more energy than other batteries, researchers say.
+The virus batteries could be thin, transparent, and lightweight, according to a US study published online recently in the journal Science by Professor Angela Belcher of the Massachusetts Institute of Technology and team.
+Because less material is devoted to packaging, more of the battery is used just for generating power. 
+"What we're trying to do is have all of the mass and volume be used for the purpose it is to be used for, which is to power the device," says Belcher.
+The researchers say such a battery should last as long as conventional batteries. And it could power anything from microelectronics, including chemical and biological sensors, 'lab on chip' devices, and security tags to larger items such as mobile phones, computer displays and even electric cars. 
+Building batteries, like building anything, requires assembly. The smaller the battery, the more challenging that is. 
+Current manufacturing techniques involve arranging nanoparticles, nanotubes, or nanowires on surfaces using expensive, high-temperature methods. 
+Belcher and her team decided to capitalise on biology's inherent knack for organising microscopic structures and apply it to battery technology. 
+Viruses acting like wires?
+To make the viruses work like conducting wires, the scientists genetically altered the organisms so that proteins on their surfaces would be attracted to metal particles, including cobalt and gold. 
+Four different solutions went into the battery component: a negatively charged polymer, a positively charged polymer, negatively charged viruses, and charged particles, or ions, of cobalt. 
+The scientists spread the negatively and positively charged polymer solutions onto a glass slide in alternating layers. Next, they dipped the slide into a solution containing millions of the altered viruses. 
+The wire-like viruses automatically spread themselves evenly across the slide, as they have a natural tendency to slightly repel each other. 
+When the slide was dipped into the ion solution, proteins on the surface of the viruses attracted the metal ions, causing the organisms to become, essentially, conducting wires. 
+And because viruses naturally replicate, scientists say that growing more to make many batteries shouldn't be hard. 
+"All you do is grow them in a bigger fermenter and you're done. Once you do, there's no roadblock to scale up to industrial level production," says Brent Iverson, professor of chemistry and biochemistry at the University of Texas at Austin.
+Building anodes and cathodes
+When the polymer solution dries, it becomes a transparent anode, the battery's positively charged terminal.
+A piece of film about 10 centimetres by 10 centimetres contains about a billion conducting viruses.
+Belcher and her team are working next to produce the negatively charged cathode with the viruses and believe they will have a working prototype in about two years.
+
+Melting ice is depriving polar bears of their habitat, says a new report, making them a vulnerable species
+Polar bears and hippos have joined the ranks of species threatened with extinction from climate change, unregulated hunting and other human-made dangers, says a leading environmental agency. 
+The World Conservation Union, or IUCN, says more than 16,000 species of animals and plants are at risk of disappearing, including one in four mammals and one in eight birds. 
+It added 530 species to its 'Red List' of endangered species since the last version released two years ago. 
+Australia, China, Brazil and Mexico are home to large numbers of threatened species, says the IUCN.
+Its members include 81 governments, more than 850 non-governmental groups and some 10,000 scientists from around the world.
+The agency says countries worldwide need to boost efforts to preserve biodiversity through reduced emissions, tighter fishing and hunting controls and other measures. 
+Without a reversal of global warming trends, it predicts polar bear populations would drop more than 30% in the next 45 years as melted ice caps deprive the animals of their habitat. 
+It classifies the polar bear as a 'vulnerable' species, one step down from 'endangered' in its ranking of extinction risk. The polar bear was previously called a less-severe 'conservation dependent' species. 
+The common hippo was also ranked as vulnerable, "primarily because of a catastrophic decline in the Democratic Republic of Congo", the IUCN says. 
+Unrestricted hunting has caused a 95% decline in the central African country's hippo population since 1994, it says. The animal has never before been listed as threatened.
+Critically endangered
+Dama gazelles, once the most populous species of gazelle in the Sahara desert, are now 'critically endangered' as a result of poaching, the report finds.
+More than half of the Mediterranean's 25 endemic species of freshwater fish are deemed to be at risk of extinction, along with one in four of East Africa's freshwater fish. 
+In Malawi, where freshwater fish account for 70% of the animal protein that humans eat, the numbers of lake trout in Lake Malawi have halved in the past decade. 
+"This could have major commercial and dietary consequences for the region," the IUCN says. 
+Ocean life is also cited as vulnerable. Of 547 species of sharks and rays assessed in the report, 20% are found to be at risk of extinction. Bottom-dwelling species also logged huge declines as fisheries have reached into ever-deeper waters. 
+"Populations are destined to decline in the absence of international catch limits," the report says, adding regulations on mesh size and non-fishing areas could help restore stocks. 
+Conservation can work
+World Conservation Union director general Achim Steiner says resurgent populations of white-tailed eagles in Europe shows that protective measures can protect vulnerable species.
+"Conservation measures are making a difference," Steiner says.
+For example, on Australia's Christmas Island, the seabird Abbott's booby was declining due to habitat clearance and was listed as 'critically endangered' in 2004.
+But the booby is recovering thanks to conservation measures and has now moved down a category to 'endangered', the IUCN says.
+
+Scientists say that terrestrial gamma-ray flashes could spark cloud-to-cloud lightning
+The ongoing hunt for the sources of exotic gamma rays inside Earth's atmosphere has taken two strange turns. 
+One is that the powerful radiation flashes are being triggered far closer to the ground than ever suspected.
+The other is that in at least one case a burst of gamma rays appears to have happened before a burst of cloud-to-cloud lightning, like a lightning trigger. 
+Terrestrial gamma-ray flashes are thought to occur when electrons that have been somehow sped to near light-speed slam into air molecules.
+The great burst of energy the collision releases is enough to create gamma rays, one of the most powerful form of electromagnetic radiation. 
+Researchers have thought they were in some way associated with sprites, the enigmatic vertical bolts of lighting that zap upward from very high cloud tops towards space.
+But new US research with an array of ground-based and space-borne instruments has located the gamma-ray sources much deeper in the Earth's atmosphere, in thunderstorms. 
+The finding, reported recently in the journal Geophysical Research Letters, is puzzling because the thicker air of the lower atmosphere gobbles up gamma rays pretty quickly. 
+"Sprites were the logical choice [for a link with gamma-ray flashes]," says lead author Dr Mark Stanley of the Los Alamos National Laboratory. 
+Not only are they flashy and energetic, they are also close to the edge of space, which would easily allow the gamma rays to escape the atmosphere and reach orbiting detectors. 
+"But there's nothing there and that's quite a shock," says Stanley.
+High flashes and low ones
+The researchers took new measurements using the ground-based Los Alamos Sferic Array, which detects electrical changes in the atmosphere, and the gamma-ray detector onboard the orbiting Ramaty High Energy Solar Spectroscopic Imager.
+Their results indicate the terrestrial gamma-ray flashes are coming from much lower down, and come from cloud-to-cloud lighting in much thicker, gamma-ray absorbing air. 
+That means the exact source of the gamma rays has to be putting out a lot more gamma rays so a few can make it up into space and be detected. 
+"If you detect this at any distance that means whatever causes this is incredibly violent," says Stanley.
+Stanley and his colleagues have found terrestrial gamma-ray flashes that appear to come from less than 15,000 metres up, within the range of jet aircraft.
+"I'm getting some even lower than that," Stanley says.
+Perhaps terrestrial gamma ray flashes are created at various elevations, says lightning researcher Assistant Professor Steven Cummer of Duke University.
+Those that are higher can be only detected by the orbiting imager and those that are lower can be detected only on the ground.
+Which came first? The gamma rays or the lightning?
+Stanley and his colleagues also refined the timing of the events and in one case found that the gamma rays detected by the orbiting imager might have preceded the lightning, which was a complete surprise, he says. 
+"In every way this was unusual," says Stanley. 
+Until now it had been assumed that the terrestrial gamma-ray flashes were a product of the lightning initiation process. Now it also appears possible that they could also play a role in triggering lightning. How? 
+"It's really not at all that well understood," says Cummer.
+Despite centuries of research to unlock the secrets of lighting, including Benjamin Franklin's discovery of its electrical nature,  Cummer says "nobody really knows what starts a lightning strike".
+
+Male praying mantises have one of two types of genitalia, say researchers, the first time anyone has seen this type of dimorphism in insects
+Some praying mantises have genitalia that hang to the left and others to the right, says a behavioural ecologist.
+But Greg Holwell, an Australian post-doctoral researcher at Macquarie University, says he doesn't know why.
+Holwell reported this unusual trait at the recent Australasian Association for the Study of Animal Behaviour conference in Sydney.
+Holwell travelled to Queensland hoping to study sexual cannibalism in praying mantises, or mantids. But he got more than he bargained for.
+Rather than finding examples of females eating males, he found a unique case of dimorphism, where there are two distinct forms of a particular species.
+He found the males of the species Ciulfina are identical except they have genitalia that are the mirror image of each another.
+"Their genitalia point in one direction or the other, which is a very unusual phenomenon," says Howell.
+He knows they are both the same species because he's mated left and right-handed males with females and they've produced offspring that have survived. DNA studies also show they are the same species.
+"This is really a big thing," he says.
+A rare find
+Dimorphism is quite common, for example, males and females of the same species. But it is extremely rare within a particular sex, says Holwell.
+"What's even rarer is dimorphism in genitalia," he says.
+This is why so many species distinctions, particularly in insects, normally rely on differences in genitalia.
+Holwell says there are only two other known cases of dimorphism in genitalia, one involving female spiders and other involving male thrips.
+But the mantids are the first to show mirror-image genitalia.
+"It may just be a genetic mutation that's occurred at some point and because left and right-handed males don't have any particular advantage over another, both forms have survived in the population," he says.
+The male mantid's genitals consist of a number of components that enable the male to stimulate the female, attach to her and transfer packets of sperm called spermatophores.
+The females are perfectly symmetrical, says Holwell, which means asymmetrical males must twist their abdomen to mate with the females. 
+The direction of the twist depends on which way they hang.
+More strange behaviour
+Holwell's colleagues have also found that when males transfer a sperm packet to females, some of it is inserted into the female and some is left hanging out.
+"Some time after mating the female does a kind of a yoga twist, pulls her abdomen up to her face, pulls the spermatophore out and eats it," says Holwell.
+The researchers want to find out whether the female eats empty sperm packets, which means she is just 'tidying up'.
+But Holwell says if she removes packets still containing sperm, this might be her way of controlling which male gets to fertilise her.
+
+Comatose patients lose their muscle tone, have feeding tubes and often open their eyes, hardly the stuff of movies
+Portraying coma patients in movies as 'sleeping beauties' misrepresents reality and could skew the way we think and deal with coma in real life, researchers report.
+They say showing people suddenly awakening after years in a coma with no physical or mental problems, or depicting long-term comatose patients peacefully 'sleeping' with perfect grooming and a healthy tan, minus any feeding tubes or loss of muscle tone, is unrealistic.
+The concern is that these images become 'real' for everyday people and may well influence the decisions they would make if faced with a similar situation, researchers report in the journal Neurology.
+Dr Eelco Wijdicks, a fellow of the American Academy of Neurology, reviewed 30 movies from around the world that depict prolonged coma and found that only two characters showed a reasonably accurate representation.
+Wijdicks and colleague then showed clips of scenes from some of the movies to 72 people with no medical training.
+More than a third couldn't identify important inaccuracies in the scenes.
+For example, 31% shown a comedy scene where a comatose person tapped out a message with his finger in morse code believe it could happen in real life. 
+And 39% of those surveyed say they would allow the scenes to influence decisions they make if a family member is in the same situation.
+Australian consultant neurologist Associate Professor Richard Burns, who is based at Flinders University and Repatriation General Hospital in Adelaide, says he takes movie scenes of comatose patients with a pinch of salt.
+"There is this rare instance where someone does recover from prolonged coma and does seem to be all right. But that would be one in 10,000 or even more. But it does make it difficult when you are explaining to relatives that there is no hope," he says.
+Burns says he can't remember a person in a prolonged coma "just suddenly waking up". 
+He believes movie makers have a responsibility to depict coma accurately.
+[But] it's unrealistic to expect them to do it because they like to show the exceptional."
+
+Eggplants and other ingredients of ratatouille become more acidic if you roast them in the oven
+Cooked vegetables can be as acidic as tooth-eroding fizzy drinks, scientists warn. 
+Eggplants, green capsicum and zucchini become more acidic when roasted in the oven, while red capsicum becomes heavily acidic when stewed, according to a study at Scotland's University of Dundee.
+But the acidity of onions or tomatoes does not change with the cooking method.
+Dr Graham Chadwick publishes his findings in the current issue of the European Journal of Prosthodontics and Restorative Dentistry.
+The researchers study was prompted by reports that people on a vegetarian diet may be at risk of dental erosion. This is because the large quantity of foods that they eat, such as fruit and vegetables, tend to be quite acidic.
+So the researchers studied how different methods of cooking a vegetarian dish like ratatouille could affect its acidity. 
+Ratatouille was acidic no matter how it was cooked, but oven-roasting significantly increased the acidity of the dish, compared with stewing. 
+"The acidity of ratatouille prepared by oven-roasting is the same as that of some carbonated drinks that, when consumed in excess, are believed to contribute to the development of dental erosion," says Chadwick. 
+Acid can etch into the thin layer of enamel that protects the teeth and can also affect the underlying dentin.
+Earlier this year, researchers presented research into the corrosive potential of acidic drinks at the American Association for Dental Research annual meeting in Florida.
+The University of Iowa researchers found that drinks including fizzy drinks and apple juice can erode exposed root surfaces.
+
+Saturn's gassy nature makes its difficult for scientists to 'see' the length of a day
+Saturn is spinning slower than expected, scientists report. 
+An international team of researchers has calculated the rotation period is 10 hours and 47 minutes.
+That's 8 minutes longer than estimates from the NASA Voyager results in the early 1980s. 
+It may not sound like a lot but the researchers say it could affect how we calculate the size of the planet's rock and ice core, and provide more insights into how it formed. 
+The team publishes its results today in the journal Nature. 
+"Making this measurement has been one of the team's most important scientific goals," says Professor Michele Dougherty, of Imperial College London. 
+Astronomers have long tried to calculate the length of a Saturn day. William Herschel back in the late 18th century for example, suggested it lasted about 10 hours.
+But the nature of Saturn itself makes measurements difficult.
+Unlike Earth which has a rocky surface, Saturn is made up mostly of hydrogen and helium gases, which complicates how scientists measure the length of a day.
+So rather than take direct measurements, scientists use proxies, or markers, of the planet's rotational period.
+In the 1980s, scientists analysed radio signals from Saturn picked up by Voyager to calculate the length of day.
+Now, Dougherty and US scientists used an instrument called a magnetometer on the Cassini spacecraft, which measures the planet's magnetic field.
+By analysing data collected by Cassini they found a clear period in the planet's magnetic field that they suggest indicates a day lasts 10 hours, 47 minutes and 6 seconds, give or take 40 seconds. 
+"The period we found from the magnetic field measurements has remained constant since Cassini entered orbit almost two years ago, while radio measurements since the Voyager era have shown large variability," says Dr Giacomo Giampieri, the lead author of the study from NASA's Jet Propulsion Laboratory. 
+"By measuring the magnetic field over the rest of the mission, we will be able to solve this puzzle."
+
+Australia can expect a drier east and north if a crucial Pacific current continues to weaken, scientists say
+The vast looping system of air currents that fuels Pacific trade winds and climate from South America to Southeast Asia may be another victim of climate change, scientists say.
+This could mean more El Ni&ntilde;o-like weather patterns in the US, more rain in the western Pacific and less nourishment for marine life along the Equator and off the South American coast.
+And Australia's north and east would probably be drier than normal.
+Known as the Walker circulation, this system of currents functions as a huge belt stretching across the tropical Pacific, with dry air moving eastward at high altitude from Asia to South America and moist air flowing westward along the ocean's surface, pushing the prevailing trade winds. 
+When the moist air gets to Asia, it triggers massive rains in Indonesia. Then it dries out, rises and starts the cycle again, heading east. 
+This important system has weakened by 3.5% over the past 140 years, and the culprit is probably human-induced climate change, scientists report in today's issue of the journal Nature. 
+"This is the impact of humans through burning coal, burning benzene, gasoline, everything," says author Dr Gabriel Vecchi of the US National Oceanic and Atmospheric Administration and an author of the study. 
+"It's principally the greenhouse gases from fossil-fuel burning." 
+The observed slowdown has been more pronounced in the past 50 years, Vecchi says, noting this fits with what theorists and computer models predict should happen as a result of human-induced global warming. 
+It is not consistent with any natural fluctuation in the system, Vecchi says. 
+Even this relatively small weakening in the Walker circulation means a much larger slowing of wind-forced ocean currents, the scientists say.
+This could spur El Ni&ntilde;o-like effects, Vecchi says, and these in turn could have an impact as far as the US, South America and Australia. 
+While these potential effects are being studied, Vecchi says it could mean more rain in the southern US, droughts elsewhere in North America, and more rain in Pacific islands like Kiribati. 
+The slowdown in ocean currents is also expected to cut down on bottom-to-top ocean circulation that brings nutrients up to the surface where marine life can feed on them, the scientists say.
+This could affect fishing in the equatorial Pacific. 
+The weakening of the Walker circulation is projected to continue, and could weaken another 10% by 2100, the scientists report.
+This could mean ocean flow could decrease by close to 20%.
+According to Australia's Bureau of Meteorology, as the Walker circulation weakens, say during an El Ni&ntilde;o event, seas around Australia cool and slackened trade winds feed less moisture into the Australia-Asia region. 
+This means that eastern and northern Australia will probably be drier than normal.
+
+China reportedly has up to 36.8 million blog sites
+China's internet minders have vowed to step up controls of internet content, especially in the most active areas of blogs, bulletin boards and search engines, state media said this week. 
+"As more and more illegal and unhealthy information spread through blogs and search engines, we will take effective measures to put the BBS [bulletin board service], blogs and search engines under control," Xinhua news agency quoted Cai Wu, a government spokesman as saying.
+China was taking steps to make registration mandatory on millions of blog sites and BBSs, or sites where internet users can converse online, Cai said. 
+According to a report by Tsinghua University, quoted by Xinhua, China currently has up to 36.8 million blog sites, a figure that could grow to 60 million by the end of the year.
+The number of search engine users had reached 97 million, or about 87% of all internet users, the report said. 
+"We will speed up the technology development to safeguard the network management and do more research on the internet security issues triggered by the new technologies in blogs and search engines," the report quoted Wang Xudong, Minister of Information Industry, as saying.
+China has for years been waging an online battle to censor the internet of pornographic and violent content, while also stifling political and religious material that it believes could spark social unrest.
+Two years ago all Chinese web portals were required to register with the government, while they also signed on to government issued regulations to self-police their sites for "unhealthy content".
+Rules at the time also required all Chinese internet cafes to register web surfers and not allow them to download or upload any content onto or from personal devices. 
+Human and media rights groups say China's leaders are tightening their control over the internet and traditional press amid increasing social unrest and regularly jail journalists and internet commentators who post anti-government material on the web.
+
+A new domestic windmill could help bring wind power closer to home, and be safer for birds
+People could soon generate their own wind energy with a new type of domestic windmill that plugs straight into the grid.
+The windmill, which is still at the prototype stage, differs from others already available as it needs fewer components to operate and is said to be cheaper.
+Its Australian developer, The SolarShop, in Adelaide says it's also safer for birds compared to larger windmills.
+The company this week received a Commercialising Emerging Technologies grant from the Australian government to develop the product further.
+Current domestic-scale wind turbines produce around 24 to 48 volts and rely on costly inverters to convert this to 240 volts, says Adrian Ferraretto, managing director of The SolarShop.
+The new generator will eliminate the need for an inverter, the company says, and will be cheaper than alternatives on the market.
+Feeding electricity back into the grid enables a householder to turn their electricity meter backwards and get credit on their electricity bill.
+Ferraretto says that over a year, with an annual average wind speed of 6 metres per second, the generator would produce around A$2000 worth of electricity.
+Wind farms typically require an annual average wind speed of 8 metres per second, he says.
+Not quite roof-top
+The windmill needs a windy area, free of nearby trees and buildings, to work.
+"It's really site-specific," says Ferraretto. "You don't want to put it in the wrong spot or you'll be throwing your money away." 
+"We think the main market will be coastal acreages around Australia and the world." 
+He says people will probably prefer to mount the generator on a free-standing tower away from the house.
+"People with beautiful homes wouldn't want one of these on their roof," says Ferraretto.
+
+King Tutenkhamen's penis was there all along, scientists say. It wasn't stolen and sold, as rumours suggested
+King Tutankhamen's rediscovered penis could make the pharaoh stand out in the shrunken world of male mummies, scientists say.
+They've taken a close look at old pictures of the 3300-year-old mummified king. 
+His sexual organ has been just another puzzle in the story of the best-known pharaoh of ancient Egypt.
+Harry Burton (1879-1940) photographed the royal penis intact during Howard Carter's excavation of King Tut's tomb in 1922.
+But it was reported missing in 1968, when UK scientist Professor Ronald Harrison took a series of x-rays of the mummy. 
+There was speculation that the penis had been stolen and sold. 
+"Instead, it has always been there. I found it during the CT scan last year, when the mummy was lifted. It lay loose in the sand around the king's body. It was mummified," says Professor Zahi Hawass, chief of Egypt's Supreme Council of Antiquities.
+At first look, Burton's pictures may seem to indicate that King Tut could have been a little better endowed. 
+But according to mummy expert Dr Eduard Egarter Vigl, the pharaoh was built normally.
+Egarter is caretaker of &Ouml;tzi the Iceman, the world's oldest and best-preserved mummy, and was also a member of the Egyptian-led research team that examined King Tut's CT scan images. 
+"The pharaoh's sex organ is clearly visible in Burton's pictures. All was normal in King Tut. The penis is a highly vascularised organ and shrinks when it is mummified. Actually, King Tut has been flattered by the embalmers' work. There is no comparison with &Ouml;tzi's penis," says Egarter. 
+Mummifying the penis
+&Ouml;tzi's natural mummification and dehydration in an Alpine glacier produced a "collapse of the genitalia", which left the Iceman with an almost invisible member. 
+"He would not make a bella figura today," Egarter says.
+According to the mummy expert, it is not possible to see if King Tut was circumcised.
+Eugene Cruz-Uribe, professor of history at Northern Arizona University and an expert on Tutankhamen, says that some earlier documents mention circumcision at King Tut's time. 
+"It was probably done for hygienic reasons, but some ritual issues may have occurred as well," Cruz-Uribe says. 
+Boy as king
+Tut.ankh.Amun, "the living image of Amun", ascended the throne in 1333 BC at the age of nine, and reigned until his death in 1325 BC, aged 19. 
+He married 13-year-old Ankhesenpaaten, who was probably his stepsister, on his accession to the throne.
+During their marriage, Ankhesenpaaten, who had changed her name to Ankhesenamun, gave birth to two stillborn girls.
+
+This gelatinous zooplankton Athorybia was among the many species scientists found deep in the ocean
+Scientists have found 10 to 20 new species of tiny creatures in the depths of the Atlantic, says an international report.
+The survey, of tropical waters between the eastern US and the mid-Atlantic ridge, used special nets to catch thousands of species of fragile zooplankton.
+New finds included six types of ostracods, a shrimp-like creature, and other species of zooplankton such as swimming snails and worms. 
+Zooplankton are mostly millimeters long but range up to jellyfish trailing long tails.
+They live at lightless depths of 1 to 5 kilometres and are swept by ocean currents.
+"This was a voyage of exploration ... the deepest parts of the oceans are hardly ever sampled," says Dr Peter Wiebe, the cruise's scientific leader and senior scientist at the Woods Hole Oceanographic Institution in the US. 
+"We found perhaps 10-20 new species of zooplankton," he says of the voyage by 28 scientists from 14 nations, including Australia, in April.
+The scientists also found new fish.
+Among 120 types of fish caught, the scientists found what may be a new type of black dragonfish, with fang-like teeth, growing up to about 40 centimetres, and a 20-centimetre-long great swallower, with wide jaws and a light-producing organ to attract prey. 
+Most life, including commercial fish stocks, is in the top 1 kilometre of water, but the scientists say the survey shows a surprising abundance even in the depths.
+The survey will provide a benchmark to judge future changes to the oceans, the scientists say.
+"By 2010, the research ... will provide a baseline against which future generations can measure changes to the zooplankton and their provinces, caused by pollution, over-fishing, climate change, and other shifting environmental conditions," says Professor Ann Bucklin, lead scientist for the zooplankton census project at the University of Connecticut.  
+The expedition was funded by the National Oceanic and Atmospheric Administration.
+The findings are also part of a wider Census of Marine Life trying to map the oceans.
+
+Sitting in silence might be better for your heart
+Turning off relaxing music and sitting in silence is better for your health, say Italian and UK researchers.
+They found while slow meditative music induces a relaxing effect, it's the gap between the music that has greater benefits for your circulation system.
+Dr Luciano Bernardi of the University of Pavia and colleagues report their study in a recent issue of the journal Heart.
+The research was part of a wider look at how heart rate, blood pressure and breathing rate fluctuate in response to music.
+Bernardi and his team asked 24 men, half practising musicians, to listen to a random series of six 2 minute musical tracks.
+The tracks included raga, a type of Indian music; slow and fast classical music; techno; rap; and dodecaphonic, or 12-tone music that lacks a traditional rhythmic, harmonic and melodic structure.
+The researchers then measured their heart rate, breathing, blood pressure and other indicators of arousal or relaxation.
+They repeated the experiment inserting 2 minute periods of silence.
+The researchers found that most of the music increased blood pressure and heart rate, with a stronger effect seen with faster music.
+This effect did not appear to depend on the style of music. So, fast classical music and techno had the same effect.
+Relaxing with music
+Slow music produced a more relaxed affect, especially during the pauses.
+But during the silent interval, study participants' heart and breathing rates and blood pressures fell further.
+"[Therefore] music may give pleasure (and perhaps a health benefit) as a result of this controlled alternation between arousal and relaxation," Bernardi says.
+In musicians, the silent interval also reduced activity of the sympathetic nervous system, which triggers the 'fight or flight' response. 
+The musicians also had more pronounced shifts in heart rate and breathing when they heard the music, which the researcher says is probably associated with their ability to synchronise their breathing with the music phrase.
+Listening to music may have effects similar to that of relaxation techniques, Bernardi and his colleagues note.
+Focus then release
+This generally requires a person to focus his or her attention on something and then release it.
+"Appropriate selection of music, by alternating fast and slower rhythms and pauses, can be used to induce relaxation and reduce sympathetic activity and thus may be potentially useful in the management of cardiovascular disease," the researchers conclude.
+
+A UK government says UFOs may be just glowing clouds of plasma
+British defence authorities have come up with an explanation for UFOs that is bound to disappoint those who are convinced they've seen a flying saucer.
+A Ministry of Defence report, which will be made public later this month, says what UFO watchers may be seeing unusual atmospheric effects like glowing plasma clouds.
+"Considerable evidence exists to support the thesis that the events are almost certainly attributable to physical, electrical and magnetic phenomena in the atmosphere," the report concludes.
+Plasma is an ionised gas described by Sir William Crookes in 1879 as 'radiant matter' because of its tendency to glow.
+A plasma effect is also responsible for spectacular auroras like the northern lights (aurora borealis) and southern lights (aurora australis), says astronomer Dr Paul Francis of the Australian National University.
+Francis says he sometimes investigates reported UFO sightings at the Mount Stromlo Observatory, where he is a fellow, and plasma clouds provide a plausible explanation.
+"It's quite clear that there are lights in the sky that people really do see and it's quite clear they're not aliens," he says.
+Radiant matter
+Plasma clouds are electrically conductive collections of charged particles.
+They form when there's an equal distribution of positive and negative charges, making the overall charge neutral.
+"A plasma cloud is going to be by nature composed of electrons and ions," says Professor Iver Cairns, a space physicist from the University of Sydney.
+"When they recombine to form atoms they're going to release light and therefore they will glow."
+He says plasma clouds tend to stick together but they can be shaped by magnetic forces and factors like winds in the normal atmosphere.
+Lightning can also cause plasma clouds, Francis says.
+"Whenever you get a lot of energy such as a lightning bolt, or an aurora caused by the winds of the Sun, this generates plasma," he says. 
+"Gas has to be pretty hot to turn into plasma."
+Ball lightning
+Professor Bob Vincent from the school of chemistry and physics at the University of Adelaide says UFO observers may also be seeing ball lightning, mysterious orbs of glowing light also attributed to plasma.
+"The cause of ball lightening is still not well known and there's some discussion of whether that's plasma clouds induced by lightning," he says.
+Other explanations for UFOs have included upside-down mirages caused by light over the horizon, meteors and weather balloons, particularly at sunset, Francis says.
+Venus is commonly mistaken for a UFO and a British battleship even fired at it during World War II.
+Does plasma affect your brain?
+Plasmas can also cause "extended memory retention and repeat experiences" of UFO sightings because they generate strong electromagnetic fields which affect the temporal lobes of the brain, one newspaper report quotes the UK defence scientists as saying.
+But Francis says this is unlikely.
+"Electromagnetic fields do have an effect on people but this is a very small effect," he says.
+"If there was a plasma ball sitting three inches in front of your nose it might have some effect ... but these [clouds] are many kilometres away."
+Dr David Clarke and Gary Anthony of Sheffield Hallam University, will present findings from the report Unidentified Aerial Phenomena in the UK Air Defence Region later this week.
+The report, which they obtained under a Freedom of Information request, will also appear on the UK Ministry of Defence's website next week.
+
+Flaws in a digital image, caused by dust on the optics or natural variation between pixels, can be used to say whether a particular camera took a particular image
+A new technique matches a digital image to the camera that snapped it, scientists say, just like matching a bullet to the gun that fired it.
+The method could help bolster investigations that need reliable evidence to tie a suspect's illegal digital photos to their camera, such as in child pornography cases.
+"When a suspect is caught with images on the computer and the suspect has a digital camera in possession, the standard defence is that the images are computer-generated or downloaded from the internet," says Dr Jessica Fridrich, an associate professor of electrical and computer engineering at the State University of New York in Binghamton.
+"Imagine now that you can tie them unmistakably to the camera that is in possession of the suspect."
+Fridich and her colleagues report their method in the June issue of IEEE Transactions on Information Security and Forensics.
+In the past, forensic scientists could link print photographs to analog cameras. For example, they could match unique scratches on the negative film to the mechanical part of the camera that advances the film.
+But until now, scientists have been unable to find a cheap, reliable and robust method for locating subtle flaws in digital images and video created unintentionally by a specific camera.
+It turns out that those flaws - created by such things as dust specks on the optics, interference in optical elements and natural variations between pixels - are captured on the camera's image sensor as a unique pattern of noise.
+Capturing noise
+To isolate the 'pattern noise' created by an individual camera, Fridrich and her team took 320 images with each of nine different cameras.
+They uploaded the images to a computer and, using software they developed, analysed the images pixel by pixel.
+By assigning values to the variations found between pixels, the pattern noise, they came up with a numerical fingerprint unique to each camera.
+Once they had the numerical fingerprint, they used the mathematical process of correlation to compare the numerical fingerprints to the pattern noise from thousands of other images taken with the cameras.
+The higher the correlation number, the more likely an image came from a particular camera.
+In the forensics lab
+When using this method in a real-life situation, forensic scientists would take a bunch of digital images with the camera in question to come up with a numerical fingerprint.
+Next, they would isolate the digital fingerprint extracted from the illegal images and correlate that number with the one from the camera.
+The higher the number, the more likely a conviction.
+In laboratory experiments, Fridrich and her team matched several thousand different images to the correct camera without a single misclassification, even when images were compressed or resized.
+Dr Hany Farid, associate professor of computer science at Dartmouth College in the US, is an expert in digital image forensics.
+"This is one of the first papers out there to have what I think is a realisable, robust and effect technique for doing it," he says. 
+But Farid questions whether the method will work to distinguish a few images from the millions of potential cameras on the market.
+For now, Fridrich's technique works with digital still images, but she is hoping to soon move to scanners and digital video.
+
+Australian backswimmmers have their very own underwater oxygen supply
+Tiny aquatic bugs hitch a ride on air-filled buoyancy bubbles for minutes at a time while they fossick for food, Australian scientists show.
+This means the insects, which are about the size of a grain of rice, can stay still and out of harm's way.
+Details of how the Australian backswimmer Anisops deanei controls its depth are published today in the journal Nature.
+Backswimmers are diving insects that use their broad, oar-like legs to swim on their backs.
+While many air-breathing aquatic insects dive with air bubbles, it appears the backswimmers use haemoglobin to help keep them stationary below the surface while waiting for prey.
+The trick allows them to dive for food in the safer mid-water zone, rather than scavenge at the surface or cling to submerged objects like most other air-breathing aquatic insects, say the researchers.
+This is the ideal hunting zone for tiny aquatic bugs because at a metre below sea level, it's out of the reach of larger predators that hang around the water's surface and those that wait in deeper waters.
+Looking at bubbles
+Researchers from the University of Adelaide used a sensitive electronic balance and fibre-optic oxygen sensors to measure the gas pressure inside the bubble the backswimmer carries.
+They found that the insect uses a strategy much like a diver with a buoyancy vest to control the depth at which he or she hovers in the water.
+Backswimmers breath in a bubble of oxygen they take with them on their dive. 
+And they maintain buoyancy by releasing oxygen from the haemoglobin in their bodies, explains PhD candidate Philip Matthews from the Department of Environmental Biology.
+"The haemoglobin [acts as an] oxygen tank, so the backswimmer can carry oxygen down from the surface in this tank and then breath into their bubble as they need it before resurfacing again," he says.
+Backswimmers, found the world over, are the only insects to inhabit the mid-water zone as adults, and the only ones to possess haemoglobin throughout their entire life, a link that may be explained by the new findings.
+
+Learning a musical instrument can change the way we remember
+Musicians use unique mental processes when it comes to recognising a tune but this trait is learnt rather than inherent, a researcher says.
+PhD student David Brennan from the University of Western Sydney has shown that people with musical training appear to have different memory pathways compared to others.
+He will present his findings at a symposium on memory and the performing arts at the International Conference on Memory in Sydney in July.
+Brennan tested the ability of 72 people, including musicians and non-musicians, to recognise musical themes from popular TV shows, such as Friends, Law and Order and M*A*S*H.
+They were required to differentiate between the original theme and a transposed version where pitch, tempo, or both pitch and tempo had been changed.
+Differences between musicians and non-musicians
+Brennan found both musicians and non-musicians could identify the original theme when it was compared with a version where just the pitch or tempo was changed.
+But musicians did much better at identifying the original theme compared to a version where both pitch and tempo had been changed proportionally, or had been moved up and down by exactly the same degree.
+This suggests that non-musicians remember music as an integrated piece of information. But musicians compartmentalise elements of the music and store them as discreet blocks, Brennan says.
+"I found that non-musicians ... store the sound as a more of a composite picture, they take the entire piece of information and store it relationally between all the different aspects," he says.
+"Musicians store it as individual parameters ... for example, tempo, key and timbre."
+He says storing relational information is more efficient than storing it as separate elements but the compartmentalised approach is more accurate.
+This reflects the fact that remembering musical sequences has a lower priority for non-musicians than for those who make music their craft.
+Are musicians born or made?
+Brennan says the research suggests that learning a musical instrument can change your mental pathways.
+"It suggests that over time musicians' training leads them down particular paths of how to store information," he says.
+"I don't think it indicates any pre-wiring of brains but it certainly suggests that over a period of many years of training they allocate their perceptual resources a little differently than other people."
+The research also sheds more light on the mechanisms that govern how we remember things, Brennan says.
+"This probably represents the fact that ... as you allocate more time and training to dealing with the fine details of information you tend to store it in more separate categories.
+"Conversely, it suggests that for the many things we have to deal with that aren't focal points, we have a very elegantly efficient way of joining them into one single relationship construct."
+
+You called?
+Bottlenose dolphins can call each other by name when they whistle, making them the only animals to do this besides humans, scientists report.
+Scientists have long known that dolphins' whistling calls include repeated information thought to be their names.
+But a new study, published online today in the Proceedings of the National Academy of Sciences,  indicates dolphins recognise these names even when voice cues are removed from the sound.
+For example, a dolphin might be expected to recognise its name if called by its mother. But the new study found most dolphins recognise names, their signature whistles, even when emitted without inflection or other vocal cues. 
+More than that, two dolphins may refer to a third by the third animal's name, says study author Dr Laela Sayigh from the University of North Carolina Wilmington.
+"They are known to produce these individually distinctive signature whistles, like names," Sayigh says.
+The scientists already knew that dolphins responded to whistles, but wondered if something in the actual voice of the whistling dolphin is making the identity clear, or if the name itself is enough for recognition. 
+To find out, they studied bottlenose dolphins in Sarasota Bay, Florida. Instead of playing recordings of actual dolphins making signature whistles, the researchers synthesised signature whistles with the caller's voice features removed and played them to dolphins through an underwater speaker. 
+In nine out of 14 cases, the dolphin would turn more often toward the speaker if it heard a whistle that sounded like a close relative's. 
+"It's a very interesting finding that encourages further research, because they are using whistles as referential signals. That's what words are," says Sayigh.
+"Dolphins appear to be using these arbitrary signals to identify another dolphin." 
+She stopped short of saying dolphins might have a human-like language. 
+"I tend to shy away from using the word 'language' myself, because it's such a loaded term," Sayigh says.
+"I still really feel strongly that there is no evidence for something like our language. [Dolphins] have got the cognitive skills at least to have referential signals."
+
+Bored with khaki? Scientits say new fibres could one-day be used to make camouflage clothing change colour
+A new conductive plastic that changes colour in response to an electric field could be used in products from hue-switching camouflage gear to flexible computer displays, researchers say.
+The electrochromic polymers, developed by Dr Greg Sotzing, an associate professor at the University of Connecticut, are said to be longer and more flexible than other conductive polymers, which are short and brittle.
+"You want them to be long in length to twist them together to make thread or yarn," says Sotzing.
+But it's the rigidity of the chemical structure that helps conductive polymers carry a charge in the first place.
+Until now, that stiff structure has limited how such polymers can be processed into fibres and other useful materials.
+Sotzing and his team devised a two-step method to convert flexible, non-conductive "precursor polymers" into long, conductive fibres.
+Lots of goo
+The first step is to melt or dissolve the precursor polymer into a gooey solution. 
+The researchers then apply a voltage to a special syringe and squeeze the solution through it. This process doesn't charge the polymer, but helps to evaporate solvents.
+As a result, the polymers harden and become tangled together like the strands of a rope.
+Polymers extruded by the new method can be lengthened up to about a metre and potentially much longer, the researchers say.
+At first, the fibres appear white. If the researchers dip them into a chemical solution that removes electrons, the fibres become conductive and darken to a deep blue. If the researchers apply an electric charge to add electrons, the colour changes to bright orange.
+Dr Shawn Williams is vice-president of technology at Pittsburgh-based Plextronics, a company that develops conductive polymer technology for electronic devices.
+"For a long time, people have known about electrochromic polymers, but they haven't figured out how to put them into formats that are useable and practical," he says. 
+What Sotzing has done, says Williams, is create a conductive polymer with the versatile properties of a regular polymer.
+Fabric that changes colour
+The trick for making the fibres useful for colour-changing fabrics, according to Williams, is to control the fibres on the scale of a single pixel.
+Threads with different charges could be woven together with thin metal wires designed to deliver various voltages, with the intersection between a thread and a wire serving as a pixel.
+Changing the voltage with an embedded battery would result in different colours.
+A fabric woven with the polymer fibres could be used, for example, in t-shirts bearing video advertisements or jackets that double as computers. The material could also be used by soldiers to blend into both forested and urban environments.
+Sotzing says he is speaking to both a US and international company about commercialisation.
+
+Some of us are 'extreme dreaders' whose brains register more than simple fear
+Anyone who has ever waited in dread for the dentist may find some comfort in the findings of a new brain study.
+For some people, researchers say, the waiting is indeed the hardest part, and finding a distraction might help.
+Their study, published in the journal Science, used the brain-imaging technique of functional MRI to investigate the neural mechanisms underlying dread.
+The researchers looked specifically at the agony of waiting to have a painful procedure among 32 volunteers who agreed to have a series of electric shocks to the foot.
+Some of them dreaded each shock so much that they repeatedly opted to have a higher-voltage jolt just so they could get it over with more quickly.
+These individuals, dubbed 'extreme dreaders', showed greater activity in a brain region related to both pain and attention.
+The findings, say the researchers, indicate that dread arises not from simple fear, but from the brain's attention to the unpleasant event.
+"The dread is often worse than the event itself," says lead study author Dr Gregory Berns, a professor of psychiatry and behavioural sciences at Emory University School of Medicine in Atlanta.
+He says the brain-imaging results are good news because they indicate that extreme dreaders can do something to alleviate the problem.
+They can find a distraction - such as meditation, exercise or some other activity - to take the focus off the anticipated event.
+Shocking results
+For the study, Berns and his colleagues took brain images of volunteers who agreed to endure electrical shocks to their feet.
+First, each jolt was preceded by a cue that told participants how intense it would be, for instance 60% of their maximum pain tolerance, and how long they would have to wait for it.
+In a second go, participants were presented with choices on how each shock should be delivered, with the voltage and timing of the jolt as the variables.
+For example, they could choose between having a shock at 90% of their maximum pain tolerance delivered in the next 3 seconds, or one at 60% intensity in 27 seconds.
+Extreme dreaders
+Of the 32 volunteers, nine (the extreme dreaders) consistently opted for the stronger shock to avoid the longer wait.
+This may seem illogical to many people, Berns says, but for extreme dreaders avoiding the anguished wait makes sense.
+And it was the extreme dreaders who showed particularly high activity in the brain's so-called pain matrix during the build-up to their electrical shocks.
+Activity was specifically high in areas related to attention, but not in those associated with fear and anxiety.
+In other words, extreme dreaders were giving more attention to their foot than 'mild dreaders' were.
+
+Wheatgrass contains high levels of phytonutrients, which are believed to have antioxidant qualities
+Wheatgrass juice may not be quite the tonic that many people think, according to a review that finds little evidence for many of its health claims.
+The review, published in the Australian Consumers' Association Choice magazine, concludes that while wheatgrass has some nutritional value, it's no miracle drink.
+The review found only "limited supporting evidence" for claims of the anti-inflammatory and wound-healing properties of wheatgrass and little confirmation for claims it builds red blood cells and improves circulation and tissue oxygenation.
+Wheatgrass juice is made of the pulped shoots of grasses from the genus Agropyron, is a relative of wheat and has become a staple of juice bars.
+Marketers and enthusiasts say the benefits of this dark green juice range from purifying blood to preventing cancer and making your faeces less smelly.
+"It's certainly not bad for you, but the claims that are made are perhaps a lot of hype without any real evidence," says Viola Korczak, health policy officer at the Australian Consumers' Association.
+She says larger, controlled clinical trials are needed.
+What the research says
+Choice reviewed the available scientific research on wheatgrass juice, including botanical studies, animal studies and a dozen small human trials.
+It found there are more vitamins and minerals, including calcium, vitamin C and folic acid, in 30 grams of cooked spinach, broccoli or a garden salad than in a shot of wheatgrass juice.
+Some reports link wheatgrass to improvements in eczema, fractures, burns, osteoarthritis and skin cancer, but it is unclear whether wheatgrass is directly responsible, the review says. 
+Other studies report that the green pigment chlorophyll, which makes up 70% of wheatgrass juice, shares molecular similarities with haemoglobin. But this doesn't mean it enhances red blood cell production.
+"As far as evidence goes, there's little to be found," the report concludes.
+A study of 16 patients with the blood disorder beta thalassaemia found wheatgrass juice reduced transfusions in half but not the other half.
+Meanwhile, experiments in labs and on animals showed wheatgrass may work against genetic mutations, Choice says, largely because of the antioxidant activity of some of its compounds, such as flavonoids.
+But there's no evidence for humans and "there's nothing to substantiate claims that wheatgrass can help dissolve tumours", the report says.
+Too early to write off wheatgrass juice
+Professor Marc Cohen, president of the Australasian Integrative Medicine Association and head of complementary medicine at RMIT University, says it's too early to write off wheatgrass juice
+He says it's a minimally processed wholefood with high levels of phytochemicals, which play a role in growth signalling in plants and are associated with reduced blood pressure, reduced cholesterol and cancer prevention in humans.
+"You want to be eating wholefoods so you get as many phytonutrients as possible," he says.
+Dr Peter Clifton, head of CSIRO's nutrition clinic, says wheatgrass is "very trendy ... but it probably isn't any different from any other type of grass".
+He says it may have more polyphenolics, a type of phytochemical, because it is an actively growing plant.
+This may account for one studying showing 100 millilitres of wheatgrass a day over a month reduced symptoms of ulcerative colitis, he says.
+He says claims about the health benefits of wheatgrass have been around for decades but the evidence is still lacking.
+"I guess the wheatgrass juice industry should put its money where its mouth is and test the level of polyphenolics," he says.
+
+Women can just look at a man and tell if he likes children, a new study shows
+Don't bother with months of email courtship, pay only polite attention to the advice of your friends. And as for those Jane Austen-style books on how to select Mr Right, leave them to gather dust on the shop shelves. 
+A more reliable way for a woman to judge whether a man will be a suitable mate is to look at him in the face and to trust her instincts, US scientists say.
+In a study published in Proceedings of the Royal Society B, a journal of the UK's Royal Society, psychologists test a key hypothesis about male attractiveness. 
+In a nutshell, this theory says that women are, frankly, ambivalent. They might fancy men who are hunky and macho but they also like the kind, caring types. 
+These preferences may seem contradictory, but there is a solid genetic cause for it.
+A strong, beefy, square-jawed man represents the best potential for producing a healthy baby, whereas a caring, friendly, sensitive man represents the best potential for protecting and nurturing the offspring. 
+Indeed, studies into female hormones and sex drive say a woman will find a 'masculine' face more attractive when she ovulates but switch to a more 'feminine' preference during the other phases of her menstrual cycle. 
+A team led by Assistant Professor James Roney of the University of California at Santa Barbara, has now put the theory to the test in an experiment combining psychology and hormones. 
+Looking at faces
+They recruited 39 male students aged 18 to 33, who were photographed, with their faces framed in an oval to obscure information about hairstyles, and with a neutral facial expression. 
+The men also gave saliva samples, which were assessed for levels of the key male hormone testosterone, and were asked to look at pictures of babies and to rate how much they liked children. 
+The photos were then individually assessed by 29 undergraduate women students aged 18 to 20. 
+They were asked to rate each man one a one-to-seven scale for 'likes children', 'masculine', 'physically attractive' and 'kind'. 
+They were then asked to rate the men's attractiveness as 'a short-term romantic partner (eg for a brief affair)' and as 'long-term romantic partner (eg for a committed relationship such as marriage)'. 
+The man with the child in this eyes
+The researchers found the women were uncannily accurate in guessing which men liked children and which men were less interested or indifferent to kids. 
+The men who the women considered to be more masculine and a choice for a brief fling also had higher testosterone levels than their counterparts. 
+But the men whom the women preferred for a long-term relationship had a strong affinity for children. 
+Roney says these findings provide the first direct evidence that women track men's hormone concentrations and liking for children when they formulate a judgement about attractiveness. 
+Indeed, "men's interest in children may be a relatively underappreciated influence on men's long-term mate attractiveness", he says. 
+More stereotypes?
+Men may despair about this pigeon-holing, just as women have long despaired about men who stereotype females by placing them into such categories as Mother or Sex Bomb. 
+But they may also find a crumb of comfort. 
+The team saw no correlation between testosterone and liking for children. 
+In other words, Mr Macho may like children and Mr Sensitive may not. But the risk is that a woman may write them off respectively, as a long-term or a short-term mating prospect. 
+"There [may] exist somewhat independent indices of men's genetic and paternal quality rather than a single dimension in which the two aspects of mate quality trade off against one another," says the study.
+
+Flying robots, like this fictional robotic dragonfly, could bypass radar to deliver explosives or bioweapons, experts say
+It may sound like science fiction, but flying robots could make suicide bombers and hijackers redundant, experts say.
+The technology for remote-controlled light aircraft is now highly advanced, widely available, and experts say virtually unstoppable.
+Models with a wingspan of 5 metres, capable of carrying up to 50 kilograms, remain undetectable by radar.
+And thanks to satellite positioning systems, they can now be programmed to hit targets some distance away within a few metres of their target.
+Security services the world over have been considering the problem for several years, but no one has yet come up with a solution. 
+"We are observing an increasing threat from such things as remote-controlled aircraft used as small flying bombs against soft targets," the head of the Canadian secret services, Michel Gauthier, said at a conference in Calgary recently. 
+According to Gauthier, "ultra-light aircraft, powered hang gliders or powered paragliders have also been purchased by terrorist groups to circumvent ground-based countermeasures". 
+Defence on alert
+On 1 May the US website Defensetech published an article by military technology specialist David Hambling, entitled "Terrorists' unmanned air force".
+"While billions have been spent on ballistic missile defense, little attention has been given to the more imminent threat posed by unmanned air vehicles in the hands of terrorists or rogue states," writes Hambling. 
+Armed militant groups have already tried to use unmanned aircraft, according to a number of studies by institutions including the Center for Nonproliferation Studies in Monterey, California, and the Center for Arms Control, Energy and Environmental Studies in Moscow. 
+In August 2002, for example, the Colombian military reported finding nine small remote-controlled planes at a base it had taken from the Revolutionary Armed Forces of Colombia. 
+On 11 April 2005 the Lebanese Shiite militia group, Hezbollah, flew a pilotless drone over Israeli territory, on what it called a surveillance mission. 
+The Israeli military confirmed this and responded by flying warplanes over southern Lebanon. 
+Easy to buy or make
+Remote-control planes are not hard to get hold of, according to Jean-Christian Delessert, who runs a specialist model aeroplane shop near Geneva. 
+"Putting together a large-scale model is not difficult. All you need is a few materials and a decent electronics technician," he says. 
+In his view, "if terrorists get hold of that, it will be impossible to do anything about it. We did some tests with a friend who works at a military radar base: they never detected us ... If the radar picks anything up, it thinks it is a flock of birds and automatically wipes it." 
+Japanese company Yamaha, meanwhile, has produced a 95 kilogram robot helicopter that is 3.6 metres long and has a 256 cc engine. 
+It flies close to the ground at about 20 kilometres per hour and is already on the market.
+Bruce Simpson, an engineer from New Zealand, managed to produce an even more dangerous contraption in his own garage: a mini-cruise missile.
+He made it out of readily available materials at a cost of less than US$5000 (about A$6500).
+According to Simpson's website, the New Zealand authorities forced him to shut down the project, though only once he had already finished making the missile, under pressure from the US. 
+Take them seriously
+Dr Eugene Miasnikov, of the Center for Arms Control, Energy and Environmental Studies in Moscow, says these kinds of threats must be taken more seriously. 
+"To many people UAVs [unmanned aerial vehicles] may seem too exotic, demanding substantial efforts and cost compared with the methods terrorists frequently use," he says.
+"But science and technology is developing so fast that we often fail to recognise how much the world has changed."
+
+A good budget for medical research in the short term, says one expert
+The Australian government should have spent more of its budget surplus on building the nation's future r&d capacity rather than tax breaks, say commentators in the science community.
+The 2006-07 federal budget  has delivered A$5.97 billion for science and innovation and $559.6 million to universities, primarily for capital developments.
+While the government describes the spending on science and innovation as being at record level, and points to a big boost given to medical research, many say the government's spending priorities are leaving Australia behind in terms of future capacity.
+Professor Snow Barlow of the University of Melbourne says the amount spent on science and innovation may be a record in absolute terms, but as a percentage of gross national product it is decreasing.
+"It's actually lower than it's been in 20 years," says Barlow, who is a former member of the Prime Minister's Science, Engineering and Innovation Council.
+He says Australia is still investing less than competitors, including China, India and OECD countries.
+And while he welcomes increased spending on health and aged care he says investment in that area will not spawn new industries.
+"I just don't see any investment in things that might drive the future prosperity of Australia," says Barlow.
+He says there should have been more funding for the Australian Research Council, especially the council's  linkage grants, which have contributions from industry. 
+Innovative capability not addressed
+Bradley Smith, executive director of Federation of Australian Scientific and Technological Societies, agrees medical research is the big winner from the budget.
+"The budget has quite a number of welcome one-off initiatives which support infrastructure at a handful of universities and medical research institutes," he says.
+And he says there is a modest increase in research infrastructure for universities
+But he says there is a lack of commitment to education and skills development.
+"The overwhelming sense is there is still not a concerted effort by government to underpin the serious development of our innovative capability," says Smith.
+Medical research gets 'A minus'
+The budget committed an additional A$500 million over four years to the National Health and Medical Research Council, provided A$170 million for new health and medical research fellowships, A$22 million for stem cell research and over A$200 million in additional funding for medical research institutes.
+"It's a start in the right direction," says Professor Kurt Lambeck, the new president of the Australian Academy of Science.
+"As far as the medical research part is concerned I'd probably give it an 'A minus'," he says. "But other than medical there's really nothing in it that I can find."
+"In particular what I find disappointing is that there is no long-term investment in people."
+Lambeck says the new health and medical research fellowships may help stop the brain drain at the elite level, there is still a major problem for most research scientists once they finish their PhD and post-doctoral training.
+Expenditure on infrastructure is one thing, says Lambeck: "But is it going to provide the intellect to drive that infrastructure?"
+He says there should have been increased funding specifically for mid-career researchers, to provide the transition from the post-doctoral fellowships to long-term commitments.
+Short term
+And even medical researchers have reservations about the budget.
+"Overall, this is a good budget for medical research in the short term," says Professor Bob Williamson of the University of Melbourne and Chair of the National Committee for Medicine of the Australian Academy of Science.
+"The main concern that researchers will have is that, compared to Canada or European countries, we still do not use much of our wealth to create a strategic infrastructure in science, technology and education," he says.
+"The right allocation of resources for the long term should be a high priority not only for the present generation, but to ensure health and wealth for Australia in the future."
+Other allocations in the budget include:
+&bull; A$500 million to restore the health of the Murray-Darling Basin
+&bull; A$98.3 million over four years to deal with illegal foreign fishing
+&bull; A$44.2 million over three years to strengthen defences against bird flu
+&bull; A$16 million over four years to boost pest and disease preparedness
+&bull; A$15.3 million over the next four years to upgrade Questacon national science and technology centre
+&bull; A$3 million to help develop a Research Quality Framework for research funding and
+&bull; A$1.5 million per year funding increase for Australian scientists collaborating on research projects with China.
+
+New research suggests the habitat changed from dry, arid and cold to warm and wet, which led to new types of vegetion mammoths couldn't eat
+The mammoth and other species probably became extinct more than 10,000 years ago because of climate shifts, not over-hunting by humans, new research suggests.
+Radiocarbon dating of 600 bones of bison, moose and humans that survived the mass extinction and remains of the mammoth and wild horse that did not, suggests humans were not responsible. 
+"That is what this new data points out," says Emeritus Professor Dale Guthrie of the University of Alaska in Fairbanks, author of the paper in today's issue of the journal Nature. 
+"It is not that people weren't hunting these creatures. But climate would have reduced the numbers considerably," he adds. 
+Scientists have put forward various theories to explain the disappearance of the mammoth and the wild horse, Equus ferus, which coincided with the arrival of humans from central Asia in North America more than 12,000 years ago.
+One hypothesis suggests a virulent disease was responsible for the extinctions. Another theory was that by killing grazing animals, humans triggered changes in vegetation that resulted in the mass deaths. 
+The Blitzkrieg, or overkill theory, says human hunters devastated most large mammal species and drove some to extinction. 
+"But contrary to that theory, my dates show numbers of bison and [elk] were expanding both before and during human colonisation," Guthrie explains.
+His radiocarbon research shows there was a 1000-year difference between the demise of the wild horse and the woolly mammoth which Guthrie says is inconsistent with other theories.
+Instead, he suggests climate shifts transformed the dry, arid and cold region. The wetter, warmer summers led to changes in vegetation to which mammoths and wild horses could not adapt. 
+"The new patterns of dates indicate a radical ecological sorting during a uniquely forage-rich transitional period, affecting all large mammals, including humans," Guthrie adds.
+
+Triton, pictured here in the foreground, might have once belonged to a pair of passing planets
+Neptune might have nabbed its giant moon Triton from a pair of passing sister planets back when the solar system was young and when planets and their growing brood of satellites were angling for clear orbital slots around the Sun, a new study says.
+Dual systems like Pluto and its large moon Charon are not uncommon among objects in the Kuiper Belt region, located beyond Neptune's orbit, astronomers say. About 10% of the known objects in this region have partners. 
+Dr Craig Agnor, with the University of California at Santa Cruz, was sitting in a lecture about binary Kuiper Belt objects when he had the idea that Neptune may have kidnapped its main moon Triton from such a pair. 
+Triton stands out among all the large moons in the solar system because it orbits Neptune in a direction opposite to the planet's rotation, a so-called retrograde orbit. 
+Most scientists explain the moon's odd orbit and inclination by some variation of a capture scenario, a collision between objects, for example. But Agnor had long been troubled by details that did not fit with any of the interpretations. 
+"It's been this old problem to work on," Agnor says. "The existing answers, there was something just a little unsettling about them." 
+Thinking in twos
+Agnor and University of Maryland astronomer Dr Douglas Hamilton report in today's issue of the journal Nature that they used a binary system rather than a solitary object to generate a computer model of how the relationship started. And they say this solved many of the theories' flaws.
+The most troubling conundrum was accounting for the tremendous amount of speed Triton must have shed to leave itself vulnerable to Neptune's gravitational embrace.
+The collision theory, for example, would have required an impact so powerful that Triton itself should have been destroyed. 
+Scientists also have suggested that Neptune once had an extended gaseous atmosphere, which could have gradually slowed Triton until it fell into orbit around Neptune. 
+But Neptune seemed to have evolved slowly and probably never had much more atmosphere than it has today, says French astronomer Dr Alessandro Morbidelli from the C&ocirc;te d'Azur Observatory in a related Nature article. 
+Ripping off a moon
+Agnor and Hamilton show that if Neptune chanced upon a pair of mini-planets, similar to the Pluto-Charon system, the encounter could have ripped one from its partner. 
+Computer models show that the object closer to Neptune, which in this case would have been Triton, would have lost enough velocity in the process to fall into orbit around its abductor. 
+The partner object would have probably been buffeted by Neptune's gravity, passed along to Uranus and then Saturn until it finally reached giant Jupiter and was booted out of the solar system altogether, Agnor says. 
+The researchers are now curious to see if other eccentric moons in the solar system have similar life stories.
+
+Humans cause the vast majority of the 30,000 to 40,000 fires that occur across Australia each year
+Most people who deliberately light bushfires want some sort of change in their life and don't mean to cause harm, say Australian researchers.
+Dr Colleen Bryant of the Australian Institute of Criminology will present research on deliberately lit fires at the Australasian Bushfire Conference 2006 in Brisbane next month.
+"There are many reasons why people light fires," says Bryant. "People are complex and of course the motives are complex."
+While the community often views arsonists as pyromaniacs, Bryant and colleague Matthew Willis say very few deliberately lit fires are due to pyromania.
+Willis says in the majority of cases people who deliberately light bushfires do not intend to cause harm.
+They don't tend to turn their mind to consequences of lighting a fire, rather are focused on creating some change in their life.
+While some want to relieve boredom by creating havoc and excitement, other arsonists crave recognition or attention, the researchers say.
+Some light fires out of anger or protest while others believe they are being altruistic by clearing what they see as dangerous fuel-loads.
+Sometimes there are multiple motives.
+Targeting fire prevention campaigns
+Understanding the motives of people who deliberately light fires can be useful in designing fire prevention campaigns and treatment programs for arsonists, the researchers say.
+For example, Willis says people who light fires for excitement will often stay around after the fire to view their handiwork.
+He says this suggests fire crews should look around and talk to the people who are there watching.
+Knowing that some people light fires just so they can treated as a hero if they report the fire or put it out is also useful, especially for fire services screening new members, says Willis.
+"Unfortunately some of those people who light those fires do become members of fire services," he says. "So [the fire services] can use that [knowledge] as part of their recruitment exercises."
+Bryant says knowing that a certain proportion of people get a thrill out of lighting fires on extreme bushfire days also helps fire services to look out for such people on those days.
+Different types of bushfires
+As well as deliberately lit fires, there are a small number of human-caused fires that are lit without motive. These include fires due to accidents, people with mental disabilities who lack control over their actions and fires lit by children. 
+Naturally-caused bushfires, such as those that ravaged Canberra in January 2003, are usually larger and more devastating than those lit by humans. But the researchers say these account for less than 5% of all bushfires.
+They say the vast majority of the 30,000 to 40,000 fires that occur across Australia each year are caused by humans, with somewhere around 50% of these being deliberately lit.
+Willis, formerly of the Australian Institute of Criminology, analysed decades of studies including psychiatric assessments of arsonists who had lit building fires in towns and cities.
+He then adapted the findings to the bush and came up with a motive-based classification system for people who deliberately light bushfires.
+
+Rungwecebus kipunji in the wild
+A new species of monkey identified in Tanzania's highlands last year is an even more remarkable find than scientists once thought.
+It belongs to a new genus of animal, the first new living primate genus to be found in Africa for 83 years, scientists report in the journal Science.
+The new monkey, at first called the highland mangabey but now known as kipunji, is more closely related to baboons than to mangabey monkeys, but in fact deserves its own genus and species classification, the researchers report. 
+So they have re-named it Rungwecebus kipunji.
+"This is exciting news because it shows that the age of discovery is by no means over," says William Stanley, mammal collection manager at the Field Museum in Chicago, which has a dead specimen of the greyish-brown monkey. 
+"Finding a new genus of the best-studied group of living mammals is a sobering reminder of how much we have to learn about our planet's biodiversity," adds Assistant Professor Link Olson of the University of Alaska Museum, who worked with Stanley and others on the report. 
+The new African monkey, whose discovery was reported in Science almost precisely a year ago, was originally placed in the genus Lophocebus, commonly known as mangabeys. Rare and shy, it was identified only by photographs. 
+But then a farmer trapped one and it died and scientists could get a close look, including doing some DNA testing. 
+Olson's genetic analysis showed the monkey is most closely related to baboons in the genus Papio, and not to mangabeys. 
+"Had we gotten these surprising results based on a single gene, we'd have been pretty skeptical, but each of the genes we analysed either firmly supported the grouping of kipunji with baboons or failed to support a close relationship between kipunji and other mangabeys," Olson says.
+Almost a metre tall
+An adult kipunji is about 90 centimetres tall with a long tail, long greyish-brown fur, a black face, hands and feet. 
+Adults make a distinctive, loud, low-pitched 'honk-bark' call. They live in mountainside trees at elevations of up to 2400 metres and eat leaves, shoots, flowers, bark, fruit, lichen, moss and invertebrates. 
+The last new genus of African monkey to be named was Allen's swamp monkey, discovered in 1907 but not recognised as a new genus until 1923. 
+"To find, in the 21st century, an entirely new species of large monkey living in the wild is surprising enough. To find one that can be placed in a new genus, and that sheds new light on the evolutionary history of the monkeys of Africa and Eurasia as a whole is truly remarkable," says Professor John Oates, a professor of anthropology at Hunter College in New York. 
+"This discovery also reinforces the view that mountains in southern Tanzania have played an important, and until recently unexpected, role as a refuge for many species long extinct elsewhere."
+
+More than 200,000 cases of Clostridium difficile, seen here, and its cousin C. sordellii occur in the US each year, including a handful in women who have taken the RU486 abortion pill
+The cause of increasing rare but deadly bacterial infections, including a handful of cases in women who have taken the controversial RU486 abortion pill, is still unclear and needs further study, US health experts say.
+Two sometimes fatal bugs - Clostridium sordellii and C. difficile - are a particular worry as antibiotic resistance grows and infections occur in people usually not at risk, doctors and researchers say. 
+While infections have been reported in drug users, surgical patients and accident victims, including men, cases in women who took RU486 drew the most scrutiny at the Centers for Disease Control (CDC) this week.
+Officials from the CDC, Food and Drug Administration (FDA) and National Institutes of Health sought input from outside experts on what research and tracking systems are needed. 
+Dr Paul Seligman, FDA associate director for safety policy, says it is not clear what is causing the spike.
+"What we do know is that in this country we are seeing the simultaneous emergence of two virulent, often fatal illnesses affecting otherwise healthy people," he says. 
+More difficult to treat
+More than 200,000 C. difficile cases occur each year in the US, experts say. The diarrhoea-causing disease is usually manageable but has recently become more difficult to treat.
+C. sordellii is far more rare and previously was not known to be toxic. "Over the past few years the picture has changed," Seligman says.
+Drawing the most scrutiny are cases involving RU486, a drug that is taken with another called misoprostol early in pregnancy to trigger an abortion.
+Six women who took RU486, also known as Mifeprex or mifepristone, have died since 2000. Four died from clostridium infection, one was ruled unrelated, and the other is still being investigated. Officials have not directly linked the deaths to the drug. 
+The CDC says it is investigating another fatal case involving a woman who took misoprostol as part of an abortion procedure. Another fatal infection following medical abortion has yet to be confirmed. 
+Ten other deadly infections have been reported in women who had given birth or who had miscarriages. 
+More study needed
+Several women's groups and others RU486 supporters say the infections need more study, while abortion opponents say the data shows the pill is too risky to stay on the market.
+Two experts also questioned the pill. Dr James McGregor, a gynaecologist from the University of Colorado Health Sciences Center, urged officials to "reduce or eliminate" Mifeprex use. 
+Overall, panelists encouraged further study, especially on women. 
+"We clearly need controlled trials," says Dr Dale Gerding of Hines Veterans Affairs Hospital in Illinois.
+Most also say limited government data make tracking infections tough and urge better reporting systems. 
+Antiobiotics the answer?
+It is not immediately clear what action the FDA might take regarding RU486 or if officials would suggest use of antibiotics to prevent infection. 
+FDA's deputy director of the Office of New Drugs Sandra Kweder says the meeting shows "the picture is much more complicated" than the cases involving the abortion pill. 
+"This is a far more complex medical and epidemiological situation than originally might have appeared to be the case, and we'll be trying to factor that into any actions that we take," she says.
+
+Fragment B of Comet 73P/ Schwassmann-Wachmann 3 and some of the mini-comets that have broken off
+Giant telescopes around the world are capturing more spectacular views of the near-Earth disintegration of Comet 73P/Schwassman-Wachmann 3.
+The comet is now comprised of scores of fragments and zillions of tinier pieces.
+A new infrared image from the Spitzer Space Telescope of the unfolding destruction captures what looks like a line of steam engines following a common cosmic track. 
+Each 'engine' is a comet fragment boiling away plumes of dust and gas as they are blasted by the solar wind.
+The track the fragments are following is a line of Sun-warmed comet debris, dust and fine sand, that the comet left in space on its previous 5.4-year cycles around the Sun. 
+"We hadn't seen that with this comet," says astronomer Michael Kelley, a doctoral student at the University of Minnesota, Twin Cities, and member of the team that made the Spitzer telescope observations.
+"It's been suspected because it's associated with a meteor shower." 
+Comet debris streams linked to specific comets, like that seen in the Spitzer image, are the cause of many regular, predictable meteor showers.
+When Earth ploughs through the debris at the same point of its orbit each year, the debris burns up in our atmosphere, creating a meteor shower. 
+Following the debris trail
+The astronomers are hoping that by measuring the brightness of the extent of the debris trail, which can't be see in visible light, they can find out whether most of the comet vaporises from evaporating ice, the house-sized chunks seen in recent Hubble Space Telescope images, or by way of meteor-sized debris seen in the Spitzer images. 
+"We suspect that every comet goes through an episode like this," says Kelley of those comets that don't die by plunging into the Sun or into a planet. 
+It's the details that have been elusive, and why Comet 73P/Schwassman-Wachmann 3's break-up so conveniently near Earth is getting so much attention. 
+Yesterday, for instance, some brand new visible light images of the comet from 3 May were released by astronomers who caught the disintegration drama with the 8.2-metre Subaru Telescope in Hawaii. 
+"Compared to observations five days before by VLT [the Very Large Telescope, in Chile], we see some more parts coming off," says Dr Catherine Ishida of the National Astronomical Observatory of Japan, which operates the Subaru Telescope on Mauna Kea.
+One Subaru close-up of the wake of the comet's 'Fragment B' shows distinct miniature comets dropping away in the wake. Subaru astronomers have counted 13 such mini-comets.
+Big telescopes will continue to take turns looking at the comet when there is time and until the comet is too close to the Sun for the telescopes to look without damaging their instruments.
+Ishida says each new view tells another part of the story.
+"The key thing is that the comet is changing rapidly," she says.
+
+
+Scientists are using star vibrations to tell them what stars are made of
+Juggling multiple roles seems to be good for women's health, new research shows
+Juggling a career with family life may help to keep women healthy, a new study shows.
+Women who have multiple roles are less likely than homemakers, single mothers or childless women to report poor health or to be obese in middle age.
+The UK researchers report their results in the latest issue of the Journal of Epidemiology and Community Health.
+"Women who occupied multiple roles over the long term reported relatively good health at age 54," says lead author Dr Anne McMunn, of University College London. 
+"It looks like women are relatively healthy as a result of combining work and family life." 
+McMunn and her team analysed self-reported health records of more than 2000 women born in 1946.
+The scientists then tracked the women in their mid-20s and mid-50s, measuring their body mass index. 
+Information on their marital status, work history and whether they had children was also included. 
+The researchers found that women who had been homemakers most of their lives were most likely to report poor health, followed by single mothers and childless women. 
+Homemakers tended to gain weight more quickly and had the highest rate of obesity at 38% while women who were employees, wives and mothers had the lowest. 
+McMunn says it has been known for some time that women who combine employment with motherhood and partnership have better health.
+But it was not clear whether they were working and having children because they were healthy, or whether they were healthy because they were combining the two. 
+"This study is the first to show which way that direction runs," she adds. 
+"There may be potential long-term health benefits of being able to participate in all areas of society."
+
+It may look like farmyard junk but new research says it paints a unique picture of our agricultural heritage, so has great cultural value
+Farm 'graveyards', those piles of abandoned vehicles and rusty machinery that dot rural landscapes, are like cherished living photo albums and family heirlooms.
+That's the conclusion of Di Smith, a PhD candidate at Flinders University of South Australia, after studying the archaeology of farm graveyards.
+Her study, believed to be the first of its type in Australia and possibly the world, found these graveyards, are part of our cultural heritage and of great archaeological value.
+"I was looking for the answer to my questions of why do farmers keep all these abandoned vehicles and machinery on their property, why do they keep them for so long, and what do they do with them?" Smith says.
+Smith sent out questionnaires to 800 farmers - including woolgrowers, crocodile farmers, grain croppers, pig and avocado farmers - across Australia.
+Of the nearly 150 farmers who responded, 60% said they had farm graveyards, many of them inherited.
+Of those that didn't have sites, many said they used to have one and regretted getting rid of it to the scrap dealer.
+"To farmers [these sites] were very special and had a very useful purpose in recycling. It became very clear to me that they were not just rubbish dumps where [farmers] disposed of stuff and never looked at it again," Smith says. 
+She followed up her questionnaire by conducting detailed artefact surveys and inventories, mapping the sites and recording the histories of 16 farm graveyard sites across South Australia and Victoria. She then looked at sites in Alberta, Canada.
+Sites in Australia and Canada share many similarities, Smith says.
+"[But] Canadian farmers were very neat in their approach, often lining [their equipment] up in neat rows along fences, so that they are very accessible."
+Both countries' farmers are inventive when it comes to recycling, for instance, using old machinery for spare parts.
+Smith says her research gives important insight into the deeper meaning these sites hold for farmers and their families.
+"They have an important meaning as an agricultural heritage. It tells farmers who they are, where they've been and where they might be going to as far as a place that encapsulates their cultural heritage," she says.
+"To them, [the graveyards are as valuable as] a museum collection or a photo album. Because they can walk through it, and visit all these old friends along the way."
+Smith's research, which is being showcased during National Archaeology Week next week, is being considered for publication.
+
+Research into digital signal processing chips didn't live up to one researcher's promises
+The scandal of a Chinese scientist who lied about his inventions is just the tip of the iceberg in an academic environment where, analysts say, incentives to cheat are great and the risk of being found out is small. 
+Professor Chen Jin, dean of the microelectronics school at the prestigious Shanghai Jiaotong University, was fired after a government investigation found he had faked research on his Hanxin series of digital signal processing chips, authorities announce.
+The research was seen as an important step in helping China wean itself off reliance on foreign technology. 
+But a two-month investigation found Chen's chips could not perform the functions he claimed, according to the Xinhua news agency. And he used another company's research and claimed it as his own. 
+The case was discovered only after a colleague blew the whistle and after Chen, 37, had received large grants from the government and was praised as one of the country's top young scientists.
+Analysts say the case shows there are many pitfalls as the government strives to encourage its top schools and industries to come up with their own technological inventions to help the country catch up with the West. 
+Pressure on scientists and academics is also intense, leading some to take shortcuts, analysts say. 
+"In the past, academics were evaluated through a long process of monitoring their work. Nowadays ... there is pressure to show results quickly," says Dr Fan Peilei, a Chinese postdoctoral fellow at the UN University in Yokohama, Japan, who specialises in China's high-tech industries. 
+"The salary now is based on how many papers you issue, what new inventions you come up with." 
+But there is no domestic or overseas system to scrutinise Chinese researchers' work, Fan says. 
+"In Western countries, it's very open. With Chinese research, partly due to the language problem and lack of recognition that China can invent anything good, there is no one properly checking the work," she says. 
+"If there's some claim that some scientist invented something, there's no proper international review system ... The domestic supervision system is also not mature." 
+Looking to the West
+An unnamed internet commentator says online that the root of the problem is China is too anxious to catch up with technologically advanced countries. 
+"Few people ... recognise reaching the level of the West is a long-term process," he says. 
+There are fears the case could bring Chinese inventions into disrepute. 
+"This will have a negative impact on the whole chip industry," says Zhang Ming, of Hangzhou Guoxin, a company that develops computer chips for satellites and cable TV.
+The government's current five-year plan for the 2006-2010 period places special emphasis on developing an innovation-driven economy to rely less on simply being the world's factory for low-cost goods. 
+At the same time, complaints about academic corruption have been more vocal and there are signs that the government is waking up to the problem. 
+In February the education ministry urged people to report academic fraud, saying it was very concerned about the problem. 
+This year two other academics were publicly disciplined. 
+A professor at the medical school of China's Ivy League-type Tsinghua University was demoted in March after being accused of lying about his accomplishments on his CV. 
+And a Tianjin Foreign Language Institute professor accused of plagiarism in winning a professorship was dismissed after losing a lawsuit in January. 
+Granted there is a lot of good scientific research in China that is genuine, the case should serve as a warning to everyone, Fan says. 
+Fan, however, praises authorities for announcing the microchip case.
+"That's an improvement. This is very different from 20 years ago," she says. 
+Greg Shea, president of the US Information Technology Office, an industry lobby group, in Beijing agrees.
+"I think it is encouraging to see unfortunate incidents like this are coming to the attention of government officials," Shea says. 
+"The role of the education system, r&d system and government funding ... all of this is being examined and looked at with fresh eyes in light of the high level of focus on creating an innovation society ... That's good for domestic industry and foreign industry." 
+The government has banned Chen from conducting further state research and ordered him to give back investment money.
+
+Will new copyright laws protect online artists?
+The federal government's proposed changes to Australian copyright law fail to address issues facing digital artists, experts say.
+Attorney general Philip Ruddock announced the reforms this week, saying they would make the law fairer for consumers and tougher on copyright pirates.
+But Damien O'Brien of the Queensland University of Technology law school, says the revised laws profess, but essentially fail, to keep track with developing technologies and emerging markets.
+"It doesn't look like they're very radical at all," he says. "They seem fairly conservative."
+He says the new laws will let people tape their favourite TV show or download music onto their MP3 players.
+But he says they won't make life any easier for the creators of so-called internet and video mashups, which combine content from a number of different sources to produce something new.
+O'Brien, who has co-authored a paper called Mashups, Remixes and Copyright Law published on the university website, says most mashups made by unauthorised use of copyright material will remain illegal under the proposed laws.
+Mashups are an example of remix culture, which has roots in the postmodern tendency to cannibalise texts from various sources and is being driven by technology that makes this easier to do than ever before.
+For example a website could combine music from one source with images from another source and a search function from somewhere else.
+Mashups are common in music videos and websites. For example, pop star Kylie Minogue has used legal mashups in her music videos while the website ChicagoCrime mixes police data with Google maps.
+Meanwhile, the iSpecies search links data from GenBank, academic literature from Google Scholar and images from Yahoo image search.
+"The challenge ... is the extent to which mashup and remix artists should be allowed to borrow, in a seamless manner, from the past to create the future," O'Brien writes in his paper. 
+"For the first time in history creativity ... is subject to regulation."
+Professor Matthew Rimmer, an expert in copyright law at the Australian National University, agrees the proposed laws don't do much to address issues in the latest technologies.
+He says the changes go some way to recognising the use of copyright works for critique and humour.
+"But it's not a carte blanche," he says.
+O'Brien says it's disappointing that the reforms didn't include an open-ended "fair use" clause, which would be one way of mashup artists and others using copyright material legally.
+Creative commons and mashup guilds
+One way to address restrictions placed on mashup artists is through the concept of a creative common, says Jessica Coates of the creative commons project run from Queensland University of Technology.
+Under the concept, artists can license their work for use in certain ways, including a mashup.
+"The idea is that [licences] can be used by owners to make their work more widely available," Coates says.
+"If you're trying to do innovation in a digital realm it can be very hard because you're using reproductions all the time ... so the idea with a creative common licence is to try to get material out into the common realm as long as it isn't used for commercial purposes."
+Mashup guilds are another solution, says O'Brien.
+"Mashup artists can form guilds to protect themselves against copyright holders who threaten to sue them," he says.
+"It's the idea that if they form a group they can try and counterbalance the threat of litigation."
+Testing the bounds
+Rimmer says mashup artists may enjoy operating on the fringes of the law.
+"One reason that mashups have attracted such interest and popular acclaim is that they partly depend on the illegality, they depend on breaching the normal controls," he says.
+"There are always going to be people who don't seek permission and there's always going to be an innovative culture going on beyond the limits of the law."
+A draft bill including the reforms will be released shortly, the government says.
+
+The ability to plan for the future has been around for at least 14 million years, scientists say, when the apes shared a common ancestor
+Apes plan for the future, according to new research that questions whether humans are the only animals to think ahead.
+German research published today in the journal Science says apes can choose an appropriate tool to reach a treat and save the tool for the future instead of using it immediately.
+The researchers, from the Max Planck Institute for Evolutionary Anthropology, say that planning for future, not just current, needs is one of the most formidable human cognitive achievements.
+This is because it imposes a long delay between performing an action and being rewarded for it.
+The researchers let bonobo chimpanzees and orangutans select tools to reach grapes and juice bottles. 
+They chose appropriate tools half of the time, took them to their sleeping rooms then used them up to 14 hours later when retrieving the treats. 
+Both species show the skill, the researchers say, suggesting it evolved at least 14 million years ago, when all great ape species shared a common ancestor.
+"Our results suggest that future planning is not a uniquely human ability, contradicting the notion that it emerged in hominids only within the past 2.5 to 1.6 million years," they write.
+First evidence of its kind
+Associate Professor Thomas Suddendorf, a psychologist from Australia's University of Queensland, says this is the first published evidence that apes save tools for future use.
+Suddendorf, who comments on the study in the same issue of Science, says the findings also give a glimpse of our evolutionary past and provide a starting point from which researchers can begin to reconstruct the evolution of the human mind.
+"The fact that such simple performance of great apes is exciting reminds us how special and precious our foresight really is. It is so common that we take it for granted," he says.
+But he says there is no evidence yet that apes can anticipate a future mental state. For example, there is no evidence they can anticipate being thirsty when they're not currently thirsty.
+How about other animals?
+Scrub jays, birds found in the Americas, are animals that also plan for the future, the scientists say. These birds move their food around to decrease the chance of it being stolen.
+Suddendorp says some species that appear to be planning for the futures, say by building nests or hoarding food, are actually using instinctive behaviour or associative learning.
+
+Two miners walk free from a Tasmanian goldmine after being trapped a kilometre underground, highlighting the dangers of mine work
+Australian researchers are developing a computerised system that monitors the performance of miners and tells management if workers are getting tired.
+The system, designed to improve safety for haul truck operators, will be discussed at the national conference of the Cooperative Research Centres Association this week, shortly after the Beaconsfield mining disaster in northern Tasmania, in which one miner was killed and two others were trapped for two weeks.
+University of Sydney PhD student Stewart Worrell, who is being funded by CRCMining, says the sensing device wouldn't have made a difference in the Beaconsfield rockfall because fatigue wasn't an issue.
+But he says the goldmine accident, which took the life of miner Larry Knight and trapped his workmates Brant Webb and Todd Russell, highlights the danger of working in mines.
+Worrell says the technology is all about fatigue management.
+He says fatigue statistics are under-reported, but US figures for 2001-2003 show there are eight fatigue-related fatalities in mines each year.
+He says the system uses sensors fitted to the trucks and analyses data collected during haul operations, like the ability of the driver to keep to a straight line and driver speed.
+"We have sensors attached to trucks which can monitor the truck's position on the road and detect when other trucks and vehicles are nearby," he says.
+"The software analyses how a driver's performance changes over the duration of the shift and from there we can determine when there are threats and alert the driver.
+"We can detect if the truck's driving off the road or if there's a potential collision.
+"We might say 'this guy's driven over the centre of the road a couple of times so it's time to have a break'."
+Data stored on each truck is also automatically downloaded to a central database when the haul truck returns to the drop-off area.
+There, it's filtered and refined and the statistics are reported to mining management, which can then use the information to upgrade safety or predict the impact of any planned changes.
+The system is already in place in two West Australian mines and other operations in Australia and internationally are considering taking it up, Worrell says.
+He says the technology is particularly suited to a mining environment, which tends to be in an enclosed area, but it's also being considered for train drivers.
+
+Maritime enthusiasts tried to relive Captain Cook's voyage to the Pacific in a replica of his ship Endeavour. But the replica ran aground in Botany Bay in April 2005, the day before it was due to sail into Sydney Harbour. The ship is pictured here, sitting at the Garden Island naval dock, awaiting repairs
+Captain James Cook's Endeavour, the 18th century ship he sailed on his epic voyage to Australia, may be one of the four shipwrecks found off the coast of the US, archaeologists say.
+The ship is among four from a British fleet used during the US Revolutionary War found off Rhode Island.
+Researchers with the Rhode Island Marine Archaeology Project say they believe the ships, and two others previously discovered, are part of a 13-vessel transport fleet intentionally sunk by the British in Newport Harbor in 1778 to keep French ships from landing to aid the Americans' drive for independence. 
+The archaeologists says one of the 13 ships in the sunken British fleet was the Lord Sandwich, which records show was once the Endeavour, the vessel Cook used to sail the Pacific Ocean, map New Zealand and survey the eastern coast of Australia in 1768-1771. 
+Cook, acknowledged by historians as one of the greatest navigators of all time, is credited with surveying Australia's east coast on the Endeavour expedition.
+Archaeologists say it is unclear which ship could be the Endeavour. Seven of the ships in the British fleet have not been found. But they say the latest find raises the chances that one of the discovered ships is the Endeavour. 
+"There is a 47% chance that we have our hands on the Endeavour," says DK Abbass, executive director of the Rhode Island Marine Archaeology Project, a nonprofit organisation devoted to studying the state's maritime history. 
+She adds it is unlikely anything on the ships would provide a direct link to Cook.
+"Quite frankly, we could be working on her right now and never be able to prove it," Abbass says.
+It may take years to fully investigate the shipwrecks found so far, Abbass says. 
+Using historical materials and sonar, the archaeologists discovered the ships in Narragansett Bay, about about a kilometre off Newport. 
+Divers found ballast piles about 9 to 11 metres underwater, with the ship's keel and other parts embedded in the sea floor.
+They also found at least one cannon, an anchor with a 5 metre shank and a cream-coloured fragment of an 18th century British ceramic teapot. 
+Historically, the finding is significant because it helps tell the story of the siege of Newport, marking France's first attempt to aid the American insurrection against the British. 
+Though the effort failed, leaders from each side, George Washington representing the Americans and Comte de Rochambeau for America's French allies, met in Newport two years later, to formalise their cooperation for subsequent battles.
+The French ultimately helped the Americans entrap British forces on a peninsula at Yorktown, Virginia.
+"So, what you have here is the British are geared up for the colonial rebellion and now they're looking at an international conflict," says Rod Mather, an associate professor of maritime history and underwater archaeology at the University of Rhode Island.
+The shipwrecks are Rhode Island property, Abbass says. There are no plans to raise them.
+Officials estimate more than two dozen ships from the Revolutionary War period lie beneath Rhode Island's waters. They include British Royal Navy frigates, vessels from the Continental Navy and a French ship.
+
+Benzene forms when vitamin C and a preservative combine in the can
+Reports of benzene in soft drinks have been confirmed in Australia by government authorities who say the levels pose no health risk.
+A spokesperson for Food Standards Australia and New Zealand (FSANZ) says a recent study has found levels of benzene in Australian soft drinks are under 10 parts per billion.
+"These levels are very, very low," the spokesperson says. "Five years ago we wouldn't even have been able to detect it."
+FSANZ says the main source of benzene exposure for the general population is traffic pollution, air round petrol stations, and active and passive smoking.
+The spokesperson says someone would need to drink more than 20 litres of a drink to consume an amount of benzene equal to the amount breathed from city air in a day.
+"It's an exceedingly small amount," he says. "We don't believe it poses a health hazard."
+But he says any amount of benzene in food is undesirable and FSANZ is working with soft-drink manufacturers to find ways of reducing levels to a minimum.
+Vitamin C + preservative = benzene
+Benzene, a carcinogen, is found in the environment from natural and man-made sources. 
+FSANZ says soft drinks containing ascorbic acid and the preservative sodium benzoate (identified as 211) have traces of benzene.
+Ascorbic acid reacts with copper and iron found in water to from hydroxyl radicals and these radicals can react with benzoic acid to form low levels of benzene, says FSANZ.
+The World Health Organization guideline for benzene in drinking water is 10 parts per billion and the US Environmental Protection Agency has established a guidelines level in drinking water of 5 parts per billion.
+FSANZ plans to release a fact sheet on benzene in soft drinks on its website within a week to 10 days.
+Chemical mixtures 
+Dr Kate Hughes, a Sydney-based consultant on toxics to government and other organisations, says the response from FSANZ is "disappointing".
+"It doesn't really matter whether it's 10 parts per billion or whatever," says Hughes, a former toxics campaigner. "The point is it's there and it's not meant to be there in a food."
+She says studies by US scientists have shown that a mixture of small amounts of chemicals in the food chain affect the development of children.
+Hughes says that it s also significant that the presence of benzene is an unanticipated reaction between a food additive and vitamin C.
+She says it points to the creation of something that can be more toxic than the original two chemicals.
+Hughes says although there are now thousands of published examples of such synergistic reactions, health authorities do not generally consider them.
+"In the real world hazardous chemicals usually don't come by themselves, they usually come in mixtures," says Hughes.
+
+Given a choice, goats like the taste of truffles, onions, apples and garlic. But when faced with oranges, like these ones on the Greek island of Crete, they just can't refuse
+Goats and sheep prefer the taste of truffles, according to a new study that shows these ruminants have a wide palate with some suprising favourite flavours.
+The study, published in the May issue of the journal Small Ruminant Research, found that while sheep and goats have similar tastes, sheep have a more discriminating palate.
+"Flavour does appear to be more important to sheep than to goats," says Australian co-author and CSIRO Sustainable Ecosystems researcher Professor Iain Gordon.
+"We didn't test why this is the case, but it may be because goats generally have a more catholic [varied] diet than do sheep in the natural world, and so will eat a range of things with different flavours."
+In order of preference, sheep enjoy truffle, garlic, onion, apple, caramel, maple and orange flavours, according to the new research. Goats prefer truffle, onion, apple and garlic.
+Gordon and his colleagues recruited 10 male Scottish blackface sheep (Ovis aries) and 10 male feral hybrid goats (Capra hircus) as taste testers.
+The researchers treated nutritionally-enhanced food pellets with a range of synthetic, human-grade flavourings, avoiding the bitter flavours goats and sheep tend to dislike.
+After the animals fasted for an hour, the researchers presented basins containing the flavoured feeds for 30 minutes.
+By weighing each basin at the end of the taste test, the researchers determined how much food of each flavour the ruminants ate. 
+Taking the taste test
+Both sheep and goats chowed down on the more pungent, earthy flavoured feeds, shunning strawberries.
+"My view regarding these flavours is that they are highly attractive, even though rare, because of health affects associated with consumption, for example anti-parasitic [action on] worms for garlic and onion," says Gordon.
+He also explains that the researchers did not give real truffles, onions and other foods associated with the flavours to the animals because they wanted to study the animals' preferences for flavours alone, independent of nutritional content.
+Dr Alan Duncan, a nutritional ecologist at The Macaulay Institute in Aberdeen, Scotland, says the flavour rankings "make sense".
+"Both species tended to prefer flavours they might naturally encounter, such as the fungi-type truffle flavour and the onion and garlic flavours, which are found in the wild representatives of both cultivated vegetables," he says.
+"The fruity flavours tended to be avoided, and this is unsurprising since fruits do not generally feature in the repertoire of natural foods encountered by ruminant herbivores.
+"I was slightly surprised that sheep showed stronger preferences than goats. Sheep are predominantly a grazing animal, whereas goats readily consume shrubs and woody vegetation."
+Now that these preferences are known, Gordon and Duncan suggest, the flavours might be added to feed to encourage livestock to eat, particularly when new foods are introduced.
+
+We had sex with you? No!
+Our early ancestors interbred with chimpanzees after the two species drew apart millions of years ago, a new paper suggests. 
+The provocative idea is sketched by US genome experts, who have discovered that hominids and chimps diverged far more recently, and over a much longer timescale, than anyone had thought.
+During this time, the authors theorise, the two primates were rather more than kissing cousins: they had sex, swapping genes before making a final separation. 
+"The ... analysis revealed big surprises, with major implications for human evolution," says Professor Eric Lander, director of the Broad Institute of Harvard University  and the Massachusetts Institute of Technology, and co-author of the paper in today's issue of the journal Nature. 
+Until now, the belief was that humans and chimpanzees shared a common ancestor but went their separate ways around 6.5-7.4 million years ago. 
+The basis for this is a carbon-dated fossil called Toumai, whose supporters say is the oldest known human. Its critics, though, dismiss Toumai as an ape. 
+The estimate is also backed by the molecular clock, a method of calculating evolution on the basis of the speed at which genes mutate. 
+Previous molecular-clock studies have focused on the average genetic difference between human and chimp. 
+But the new paper takes a different approach. 
+Looking at DNA
+Exploiting the mountain of data that has come from the human and chimpanzee genome projects, the researchers compared the genetic codes of the two species as they are today.
+They then estimated the various age of key sequences, rather than the overall average. 
+They believe that the two species made their split no later than 6.3 million years ago and probably less than 5.4 million years ago. In other words, around 1 to 2 million years earlier than the Toumai estimate.
+Moreover, speciation of chimp and hominid, the process by which they emerged as separate species, took an extraordinary long time: around four million years in all.
+The youngest chromosome in the human genome is the X, which helps determine gender. On average, X is around 1.2 million years more recent than the 22 non-sex chromosomes, the scientists found. 
+Lander describes X's tender age as "an evolutionary 'smoking gun'". 
+Sex chromososmes
+Previous studies suggest that sex chromosomes are among the most vulnerable of chromosomes when it comes to interbreeding. This is because co-mingling places its genes under swift selective pressure. 
+Thus something unusual must have happened on the way to speciation: an initial split between human and chimp, followed by interbreeding, whose results show up in progressive younger genes, and then a final separation. 
+Lead author Dr Nick Patterson, also at the Broad Institute, says that Toumai's claimed status as humans' ancestor has been somewhat clouded. 
+"It is possible that the Toumai fossil is more recent than previously thought. But if the dating is correct, [it] would precede the human-chimp split," he says. 
+"The fact that it has human-like features suggest that human-chimp speciation may have occurred over a long period with episodes of hybridisation [inter-breeding] between the emerging species." 
+A gradual divergence of species through hybridisation, rather than a quick break, may be far more common than we suspect. 
+"That such evolutionary events have not been seen more often in animal species may simply be due to the fact that we have not been looking for them," says the team's senior author, Assistant Professor David Reich, also of the Broad Institute.
+
+The last human chromosome to be sequenced, chromosome 1, is the biggest and contains the most genes
+Scientists have reached a landmark point in one of the world's most important scientific projects by sequencing the last chromosome in the human genome.
+Chromosome 1 contains nearly twice as many genes as the average chromosome and makes up 8% of the human genetic code.
+It is packed with 3141 genes and linked to 350 illnesses including cancer, Alzheimer's and Parkinson's disease, according to a report today in the journal Nature. 
+"This achievement effectively closes the book on an important volume of the Human Genome Project," says Dr Simon Gregory who headed the sequencing project at the UK's Sanger Institute.
+The project started in 1990 to identify the genes and DNA sequences that provide a blueprint for human beings.
+Chromosome 1 is the biggest and contains, per chromosome, the greatest number of genes. 
+"Therefore it is the region of the genome to which the greatest number of diseases have been localised," adds Gregory.
+The sequence of chromosome 1 took an international team of 150 scientists 10 years to complete.
+Researchers around the world will be able to mine the data to improve diagnostics and treatments for cancers, autism, mental disorders and other illnesses.  
+Final chapter
+The human genome has about 20,000 to 25,000 genes and the sequencing of chromosome 1 has led to the identification of more than 1000 new ones. 
+ "We are moving into the next phase which will be working out what the genes do and how they interact," says Gregory.
+The genetic map of chromosome 1 has already been used to identify a gene for a common form of cleft lip and palate. It will also improve understanding of what processes lead to genetic diversity in populations, Gregory says.
+The scientists also identified 4500 new SNPs, single nucleotide polymorphisms, variations in human DNA that make people unique.
+SNPs contain clues about why some people are susceptible to diseases like cancer or malaria, the best way to diagnose and treat them and how they will respond to drugs.
+
+Could the hobbit really be one of us after all? 
+Scientists who argue the hobbit is really just a modern human with a small brain have published evidence for the first time in a major scientific journal.
+Today's issue of the journal Science carries a paper led by primate evolution expert, Dr Bob Martin of The Field Museum in Chicago, which says Homo floresiensis is likely to have been a modern human who suffered from microcephaly, a condition that causes a small brain.
+This reignites the debate about whether the remains of the small hominid from the Indonesian island of Flores is really H. sapiens or a dwarf version of H. erectus that evolved after becoming isolated on the island, as was originally suggested.
+Martin's team says that based on standard models of dwarfing, the hobbit's brain size is way too small to be that of a dwarf.
+It also argues the tools found alongside the hobbit are far too advanced to have been made by anyone but H. sapiens.
+"If you look at the history of stone tools around the world Homo erectus never made tools like that," says Martin.
+"I've been in this business for 30 years and I really smell a rat in this," he says. "I don't think the standard story can be right and people are eventually going to see this."
+His team also rejects findings of a study published last year that found the brain of H. floresiensis was unlike that of a microcephalic human.
+Martin says the study, led by brain evolution expert Professor Dean Falk of Florida State University, compared the hobbit with only one microcephalic, which he now says is a child, when the researchers should have been comparing it with a microcephalic adult.
+Martin's team describes the brains of two adult microcephalic specimens, a male from India and a female from Lesotho, it says are similar to the hobbit's.
+
+Planetary system around the star HD 69830, with its three Neptune-sized planets and an asteroid belt
+Scientists looking for planets around stars beyond the Sun have found a system that contains an asteroid belt and three Neptune-sized worlds, one of which orbits in a zone where liquid surface water could exist.
+Although the planet's location could theoretically support life, researchers believe it is wrapped in an extensive hydrogen atmosphere and probably not suitable for life as we know it.
+Nevertheless the finding, which is reported in the latest issue of the issue Nature, is considered a key development in the continuing push to find Earth-like worlds elsewhere in the universe.
+The trio of planets circle HD 69830, a pale Sun-like star about 41 light-years away in the constellation Puppis. 
+Astronomers using the infrared Spitzer Space Telescope previously discovered that HD 69830 probably has an asteroid belt in orbit. If true, the star would be the first similar in mass and age to the Sun to have one.
+The researchers also predicted that a planet's gravitational tug was helping to keep the belt in order. 
+With that hint and a sophisticated light-splitting spectrograph on the European Space Agency's 3.6-metre telescope in La Silla in Chile, astronomers spent two years studying miniscule wobbles in the star's orbit.
+Through the telescope
+They found three planets orbiting within the same distance that Earth orbits the Sun.
+Surprisingly, the hunt turned up no sign of a large Jupiter-class planet, making HD 69830 the first extrasolar planetary system without a massive planet.
+"The planetary system around HD 69830 clearly represents a Rosetta stone in our understanding of how planets form," says co-author Professor Michel Mayor, a Swiss astronomer from the Observatory of Geneva.
+"No doubt it will help us better understand the huge diversity we have observed since the first extra-solar planet was found 11 years ago."
+Hunting for more planets
+Although HD 69830's planets are still 10 to 18 times bigger than Earth, the discovery is encouraging to researchers who are refining their planet-hunting techniques to find smaller, more Earth-like worlds.
+"It implies that further low-mass planets will be spotted orbiting other stars," writes Harvard University astronomer Professor David Charbonneau in a related article in Nature.
+Computer simulations indicate the innermost planet is probably rocky, like Earth.
+The middle one is a combination of rock and gas and the outer planet, which is the one predicted to lie in the zone of habitability, is estimated to have a rocky-ice core and a massive envelope of gas.
+Researchers believe the system is stable.
+
+Blowflies have an inbuilt natural resistance to some organophosphate insecticides, scientists show
+Scientists have used crushed fly legs that are 70 years old to solve the riddle of why insects evolve rapid resistance to pesticides.
+DNA extracted from the fly legs shows that Australian sheep blowflies have an existing, advantageous genetic characteristic that allows them to resist certain insecticides.
+The research features online today in the Proceedings of the National Academy of Sciences.
+Blowflies have long created headaches for Australian sheep farmers because they lay their eggs in faecal matter around the sheep's tail, causing blowfly 'strike'.
+The pesticide diazinon was introduced into Australia in the 1950s as a sheep 'dip' to combat the problem. But within six years blowflies developed a high level of resistance to it.
+Researchers from CSIRO Entomology in Canberra and collaborators from New Zealand and the UK wanted to see if the blowflies had a pre-adaptation resistance to the insecticide.
+This would explain why they developed resistance so rapidly.
+To do this CSIRO's Dr Carol Hartley and colleagues gathered 150 samples, kept at the Australian National Insect Collection, of 70-year-old blowfly legs from two Australian sheep blowflies Lucilia cuprina and its close relative L. sericata.
+They then crushed them and extracted their DNA.
+The researchers compared the state of blowflies' resistance genes before and after the introduction of the pesticide.
+"We didn't find any diazinon resistance in the old fly legs, whereas it occurs in the present day species. That tells us that in the case of the diazinon pesticide there was no pre-adaptation."
+But when the researchers conducted the same experiment with another pesticide malathion, they found resistance genes both in the old blowflies and the modern blowflies, showing there was pre-existing resistance.
+"This is evidence for pre-adaptation as a mechanism of evolution of insecticide resistance," says Hartley.
+She says it is this pre-existing resistance that let resistance to organophosphate insecticides take off so rapidly. The specific diazinon resistance gene developed later.
+"We used the DNA from the very old flies to show that one form of the alteration already existed in the flies from 70 years ago, long before they had ever been exposed to the organophosphate chemicals," Hartley says.
+"It was this that allowed the flies to rapidly develop resistance to the organophosphate chemicals in general, after which the better version of the mutation took over in the flies."
+She says while the research mainly tells us about the mechanism of evolution  and how it occurred in these particular blowfly species, it also gives a clue to why rapid evolution of resistance can occur.
+This might help researchers predict potential insecticide resistance in the future, she says.
+
+Shampoos, sunscreens, toothpastes, anti-aging creams and other personal care products contain nanomaterials, a new report says
+Consumers are using cosmetics and toiletries that contain unregulated and untested nanomaterials, says a new report.
+The report released this week by Friends of the Earth (FOE), documents 116 products it says contain nanoparticles, a large number of which are available to Australians either in stores or online.
+"We believe this represents a small fraction of the number of products that are actually on the market," says Georgia Miller of the FOE nanotechnology project.
+Products listed in the report include well-known brands such as L'Or&eacute;al, Revlon, Clinique, Chanel and Estée Lauder, says Miller.
+The Nanomaterials, sunscreens and cosmetics: small ingredients, big risks report is based on publicly available information from manufacturers of the products or ingredients, or retailers, says Miller.
+Nanoparticles are generally those under 100 nanometres across and manufacturers are not required to label products containing them. 
+There is some concern among scientists that such tiny particles may have toxic characteristics, yet there is limited scientific information available on their safety.
+Among their concerns are whether creams and lotions containing nanoparticles can penetrate deep into the skin.
+Skin deep?
+The Therapeutic Goods Administration (TGA), which regulates sunscreens in Australia, says the weight of current evidence is that nanoparticles used in sunscreens stay on the surface or in the outer dead layer of the skin.
+But Miller points to the UK's Royal Society, which says the ability of nanoparticles to penetrate into the skin is still unclear.
+Existing studies are inadequate, says Miller, which is why there are numerous studies on skin penetration being carried out in the US and Europe.
+"We think the TGA's conclusion is very premature and irresponsible," says Miller.
+Some manufacturers promote deeper skin penetration as a feature of their nanoparticle-enhanced products, she says, pointing to anti-ageing wrinkle creams that contain fullerenes, nanoscale carbon spheres.
+"They are promoting their use of fullerenes as a positive attribute because they claim that fullerenes enable much deeper penetration into the skin of the anti-ageing ingredients," she says.
+"In a lot of instances it's the very properties that are attractive to cosmetics manufacturers, for example the ability to penetrate deeper in the skin, that are of concern to us."
+She says a 2004 US scientific study found fullerenes can cause brain damage in fish, kill water fleas, and are toxic to human liver cells even in low doses.
+Cosmetics regulator welcomes report
+Deborah Willcocks of the National Industrial Chemicals Notification and Assessment (NICNAS), which regulates cosmetics in Australia, says her organisation is "particularly pleased" to see the FOE report. 
+She says NICNAS called on industry in February this year to provide data on what nanomaterials were being used and in what volume. 
+"The Friends of the Earth report is the first time we've actually seen some published information on what products might be on the market out there," she says. "It's a good help to us."
+Willcocks says more data is required before NICNAS can determine if nanomaterials have unique toxicological properties compared ito materials with a larger particle size.
+She says NICNAS is meeting with its industry committee today and is proposing to set up a working group with industry and the community to develop a strategy on how to deal with nanomaterials.
+"We are concerned, that's why we're actually working on this very actively," Willcocks says.
+The body representing Australia's cosmetics industry, ACCORD Australasia, says it has only just become aware of the FOE report.
+Executive director Bronywn Capanna says ACCORD and its member companies would co-operate with the regulatory agencies should the report raise any relevant significant issues.
+She says examples of nanotechnology used in cosmetics and personal care products include nanoemulsions, nano-pigments and sunblocks, and nanocapsules.
+Calls for a moratorium
+The UK's Royal Society recommends nanoparticles be tested and assessed as new chemicals.
+But regulators say it is too early to say whether specific safety tests are required.
+Meanwhile, FOE is seeking a moratorium on the production and sale of products containing nanomaterials.
+"Our call is for a halt to the further release of products that contain nanomaterials until such time as we have done the safety assessment and we've got regulations in place to manage the risks," Miller says.
+The Public Health Association of Australia supports FOE's call for a moratorium.
+"[There is also no] surveillance going on to see if anything does arise out of the use of nanotechnology in things like cosmetics and sunscreens," says executive director Pieta Laut.
+
+Fossil tracks left by medium-sized wading birds. The depth and condition of the tracks indicate that the substrate was still very wet when these birds walked on the surface
+Scientists have found what they say is the first evidence of prehistoric wading birds probing for food.
+The depressions and footprints were found at Alaska's Denali National Park and Preserve in rocks scientists say were formed from freshwater sediments 65 million to 70 million years ago. 
+Such evidence of prehistoric birds' feeding behaviour is difficult to find because the marks made in the mud disappear easily and the fossilised evidence often erodes, says Phil Brease, a geologist at the park.
+Geologists discovered the tracks and marks last year. At first, they thought they were impressions left by raindrops.
+But after studying photographs and moulds, they determined they were depressions left by birds' beaks.
+The scientists say the depth and condition of the marks suggests the area was still very wet when the birds walked on the surface.
+They presented their findings at a recent Geological Society of America conference in Anchorage.
+Denali National Park is emerging to be a rich source of fossils.
+A team of geologists has also discovered a fossilised footprint of a three-toed, meat-eating dinosaur.
+This theropod would have roamed the area about 70 million years ago, the scientists say.
+
+Glowing plasma inside a fusion test reactor
+Physicists say they have cracked a problem facing nuclear fusion, touted as the cheap, safe, clean and almost limitless energy source of the future.
+The US researchers say they have found a way to cut down erosion of the metal reactor wall, which would be a crucial step to improving efficiency.
+They publish their work online today in the journal Nature Physics.
+In fusion, atomic nuclei are fused together to release energy, as opposed to fission, the technique used for nuclear power and atomic bombs, where nuclei are split. 
+In a fusion reactor, particles are rammed together to form the charged gas plasma, contained inside a doughnut-shaped chamber called a tokamak, by powerful magnetic coils. 
+A consortium of countries signed a deal last year to build the International Thermonuclear Experimental Reactor (ITER) in southern France as a testbed for an eventual commercial design. 
+But many experts have been shaking their heads at the many challenges facing the ITER designers. 
+One challenge has been the phenomenon of edge localised modes, or ELMs, sudden fluxes or eddies in the outer edge of the plasma that erode the reaction chamber's inner wall.
+The tokamak's inner wall is an expensive metal skin that absorbs neutrons emitted from the plasma. And erosion would mean that the wall would have to be replaced more often.
+Eroded particles also have a big impact on the plasma performance, diminishing the amount of energy it can deliver. 
+A team led by Todd Evans of General Atomics, California, believes that the problematic ELMs can be cleverly controlled. 
+The scientists found that a small resonant magnetic field, derived from special coils located inside a reactor vessel, creates 'chaotic' magnetic interference on the plasma edge, which stops the fluxes from forming. 
+The experiments were conducted at the General Atomics' DIII-D National Fusion Facility, a tokamak in San Diego.
+Nuclear fusion is the same process used by the Sun to radiate energy. In the case of our star, hydrogen atoms are forced together to produce helium.
+On Earth, the fusion would take place in a reactor fuelled by two istopes of hydrogen, deuterium and tritium, with helium as the waste product. 
+Deuterium is present in seawater, which would make it a virtually limitless resource. Tritium would be derived from irradiating the plentiful element lithium in the fusion vessel.
+The US$12.8 billion (A$21.6 billion) ITER scheme entails building the largest tokamak in the world at Cadarache, near the southern French city of Marseille. 
+The partners are the European Union, the US, Japan, Russia, China, India and South Korea. 
+It is designed to be a testbed of fusion technologies, with a construction period of about 10 years and an operational lifespan of 20 years. 
+If ITER works, a prototype commercial reactor would be built, and if that works, fusion technology would be rolled out across the world. 
+Other problems facing fusion technology include the challenge of creating a self-sustaining plasma and efficiently containing the plasma so that charged particles do not leak out. 
+In existing tokamaks, no one has achieved a self-sustaining fusion event for longer than about five seconds, and at the cost of using up far more energy than is yielded. 
+A huge jolt of heat of nearly 100 million&deg;C is needed to kick-start the process, which then has to be sustained by tiny amounts of fuel pellets.
+
+Today's satellite is tomorrow's space junk. But is it worth preserving?
+Plans to spring-clean space junk orbiting Earth could result in the loss of irreplaceable historical artefacts, an archaeologist warns.
+Dr Alice Gorman of Flinders University in Adelaide, an Australian researcher who has previously called for space junk to be World Heritage listed, is on a mission to preserve what she says are heritage items in space.
+She plans to take that mission to the Australian Space Development Conference in Canberra in July and to the World Archaeological Congress in Jamaica next year.
+Gorman says as space agencies prepare to de-clutter potentially dangerous space junk, it's time to assess the value of some of the millions of objects currently orbiting Earth.
+"There are a number of proposals being put forth by a number agencies and [space junk] is recognised as a very serious problem," says Gorman, who is co-chair of the World Archaeological Congress Space Heritage Taskforce.
+"There's a window of time now where we can plan to do it right."
+Culling the clutter
+Space junk ranges from tiny scraps just millimetres in size to whole satellites.
+NASA, the European Space Agency and some private organisations are already developing plans to remove it, Gorman says.
+While some space junk undergoes an "automatic clean-up regime" by burning up when it re-enters the atmosphere, other items need to be physically removed.
+Current proposals include using ground-based lasers to put objects off orbit and speed the rate of their burn-up, sending out 'space tugs' as roving garbage collectors or using tethers to rope and haul in bits of space debris.
+"To make that effective you have to be able to discriminate between what's junk and what's not," Gorman says.
+Among the items that should recognised for their heritage value are the Vanguard One satellite, launched in 1958 and the oldest human object in space, and FedSat, the Australian designed and built satellite.
+Preserving items like these could provide evidence of a nation's presence in space or help reconstruct a history of space exploration, she says.
+Woomera
+Gorman will present a report on the management of space junk at the World Archaeological Congress next May.
+"It will outline ... the heritage of space exploration, what mechanisms exist to manage [space junk], legal boundaries and which sites might be considered part of that heritage," she says.
+One of those sites is Woomera, in South Australia, which she says "played a part in a bygone era in Australia".
+"And in terms of the development of space exploration it has a much more than local significance," she says.
+
+Scarecrows have moved away from the veggie patch. Hi-tech scarecrows are now scaring birds away from fish farms, with help from the web and a mobile phone
+A computerised scarecrow could be the next defence against unwanted birds, its US developers say.
+The Intelligent Scarecrow, designed by computer science and engineering students at the University of South Florida in Tampa, uses a computer, an internet camera and imaging software to detect birds around fish ponds.
+In response, the scarecrow makes loud noises or powerful bursts of water to scare the birds away.
+Fish farmers go to great lengths and sometimes expense to keep fish-eating birds at bay.
+Deterrents include everything from tethered balloons, netting and bird-chasing dogs to propane cannons, pyrotechnics and motion-sensitive sprinklers.
+But most methods don't work well, are expensive or loud. 
+The Intelligent Scarecrow is dressed in like an American football player, with helmet and baggy jersey. But it is brains, not brawn, that make it a threat.
+The helmet conceals an internet-enabled videocamera that takes in a wide field of view, which can be accessed via a website. A microprocessor with image processing software the students wrote scans for colour and shape differences between frames.
+If the software sees bright orange, it will not trigger a response. So a farmer wearing a bright orange vest can tend crops without being seen as a threat. 
+But other changes trigger sprinklers to the right and left of the scarecrow to shoot out powerful jets of water up to 9 metres.
+Blasting the birds
+The device can also blast loud sounds, such as a shotgun noise or the cry of a predatory hawk, through nearby speakers.
+And because it's internet-enabled, the scarecrow can send a text message to a mobile phone or an email to a computer alerting the farmer of threats.
+"As far as the bird is concerned, this thing is intelligent," says Associate Professor Ken Christensen, who oversaw the students' development of the Intelligent Scarecrow.
+But the scarecrow may have a long way to go before it stands post over a pond, says Craig Watson, director of the Tropical Research Laboratory at the University of Florida in Ruskin.
+"The area it would cover is not practical with a 10- to 100-acre fish farm," he says. 
+And unless the scarecrow can move around regularly, the birds will become accustomed to it and no longer see it as a threat.
+Christensen and his students are now working to extend the scarecrow's predator detection range and water-spraying accuracy and range.
+
+Solar roof tiles would provide an alternative to conventional solar panel systems
+A roof tile that harnesses solar energy to heat water and generate electricity, has been invented by an Australian industrial designer.
+The plastic tile is filled with solar cells and connects to a house's hot water system and electrical wiring.
+Sebastian Braat, a graduate of the University of Western Sydney, says the tiles are designed with urban dwellings in mind - particularly the new generation of so-called "McMansion" style suburban homes. 
+"My project is focussing on getting the technology into the city and easing the power burden our housing estates are rapidly creating," he says.
+The tiles consist of a clear polycarbonate chassis containing a water vessel and photovoltaic cells.
+The tiles can be manufactured to match a variety of roof tile styles.
+Between 12 and 18% of thermal energy that hits the cells is converted into electricity. The remainder is used to heat the water.
+Braat says he runs a coolant through the water in the tiles, which goes to a heat exchanger. The heat exchanger transfers the heat to a regular hot water storage tank.
+Creating an energy surplus
+Meanwhile, the solar cells generate electricity as direct current that goes to an inverter connected to the house's power box, which remains connected to the electricity grid.
+ "The idea of being grid connected is that you generate loads more power than you need during the day and that gets fed back into the grid," he says.
+"That means the house in effect is generating its own power and generating the excess into the grid.
+"If the house uses more than it generates the user gets charged, if not they get a credit from the power company."
+How many tiles does it take?
+Braat says it takes about 200 tiles to generate a maximum of 1.5 kilowatts - more than enough for an average three-bedroom suburban house over a year.
+Dr Dong Chen, a research scientist with CSIRO Manufacturing and Infrastructure Technology, who wasn't involved in the design, says it makes sense to use roof tiles, or any exposed parts of a house, for solar heating.
+He says Braat may need to look at how efficient the tiles are, and the pitch of the roof may affect this.
+Chen says the inventor will also need to look at the cost of the tiles, including their maintenance, and how safe they are.
+He says it's also possible the roof could leak because the tiles may involve a number of small joints.
+
+Artificial sweeteners accelerate the emptying of the stomach and increase the rate at which alcohol is absorbed
+Alcoholic drinks made with artificial sweeteners lead to a high rate of alcohol absorption, resulting in a greater blood alcohol concentration than from drinks made with sugar-based mixers, a new study has found.
+The reason, according to an Australian team' led by Dr Chris Rayner of the Royal Adelaide Hospital, is the accelerated emptying of the stomach caused by artificial sweetening agents.
+Rayner presented his team's research at this week's Digestive Disease Week meeting in Los Angeles.
+"Today, more and more people are shifting personal preferences by choosing 'diet' drinks as a healthier alternative," says Rayner. 
+"What people do not understand is the potential side effects that diet mixed alcoholic drinks may have on their body's response to alcohol."
+Rayner and team studied eight healthy male volunteers. 
+On one day, the subjects consumed an orange-flavoured vodka drink made from alcohol and a mixer sweetened with sugar containing 478 calories.
+On the second day, the men drank the same amount of alcohol with a diet mixer containing 225 calories. 
+The researchers measured the rate of stomach emptying using ultrasound technology and took blood samples at 30-minute intervals for three hours.
+The time to empty half of the diet drink from the stomach was 21 minutes, compared to regular drinks which took 36 minutes for the same degree of emptying. 
+Peak blood alcohol concentrations were substantially greater with diet drinks at an average of 0.05%, while regular drinks measured at 0.03% blood alcohol concentration.
+"It was surprising how much of a difference the artificial sweetener made," Rayner says. 
+Rayner says these drinks also tend to be consumed at times other than meal times, when food would slow gastric emptying.
+He recommends that product labelling include information on the intoxicating qualities of artificially sweetened alcoholic drinks. 
+There could be legal implications for those driving home, as well, he notes.
+
+Before the Big Bang could have been a previous universe a lot like our own, that first collapsed and then inflated into the universe we have today
+The Big Bang may have been a Big Bounce, say theorists searching for what preceded the birth of our own universe.
+If their new mathematical simulations are correct, what came before the Big Bang was a previous universe a lot like our own. It collapsed on itself, then some weird physics caused it to inflate into the universe we have today.
+Physicist Dr Abhay Ashtekar of Pennsylvania State University and team publish their results in a recent issue of Physical Review Letters.
+What has blocked the pre-Big Bang view from theoreticians was the mathematical expression of what was happening - based on certain assumptions about space-time. 
+The problem was the calculations kept ramming up against infinity. When that happens, equations fail.
+"It's like having an impenetrable wall," says Ashtekar. "When it comes to infinity we cannot, in physics, go beyond it."
+Space-time is a model that combines three-dimensional space and one-dimensional time into a single unit called the space-time continuum. In this continuum, time is considered the fourth dimension.
+What was becoming infinite in scientists' calculations was the curvature of the space-time continuum as you near the time when everything in the universe and all the gravity was concentrated into a single point.
+Gravity shreds fabric of space-time
+The pre-Big Bang gravity basically shredded the space-time fabric and left only the physics of atoms - quantum physics - to work with.
+To peer into that unimaginable crush, Ashtekar and colleagues started gain without assuming that the "fabric" of space-time continuum existed in the earliest moments of the universe. 
+"The general belief is that the continuum may be just an approximation," says Ashtekar. "This is something even Einstein said."
+Instead, the team applied what's called loop quantum gravity, a strategy that has been developed to join quantum physics with Einstein's General Relativity. 
+Quantum theory suggests Big Crunch
+According to loop quantum gravity, the fabric of space is made of discrete and identical one-dimensional quantum threads. At the Big Bang, the fabric is a shredded mess and only these threads can be followed further back.
+Using this concept, the researchers concluded that a previous universe collapsed in on itself in a gigantic gravitational Big Crunch. 
+Then, when the density of that crunch reached super astronomical values, gravity flipped into a repulsive force - another weird outcome of this physics - and inflated the new universe in which we live.
+"It's long been speculated that as you get to the Big Bang, quantum theory was going to be important," says physicist Dr Jorge Pullin of Louisiana State University. 
+It's also been speculated that if you could work out the equations, you'd probably see that the Big Bang was a Big Bounce, he says.
+But this is the first time that anyone has actually done a thorough job working through the physics back through the Big Bang, he says.
+Previous universe elusive
+As for what it tells us about the previous universe, it's not much, says Pullin. "The only thing you can conclude is that the bounce occurs," he says.
+That's not to say we will never learn more about the earlier universe.
+Astronomers are discovering patterns in the cosmic background radiation that appear to be the inflated remnants of electron-sized irregularities in the first instant of the Big Bang. 
+Could those irregularities, combined with loop quantum gravity, reveal patterns inherited from the earlier universe?
+"There may be certain hints left behind," says Pullin.
+
+The biological clock ticks for both men as well as women
+A man's fertility appears to decline after the age of 40, in much the same way that a woman's ability to conceive fades after 35, say French researchers. 
+Dr Elise de La Rochebrochard and team, from the French national health institute INSERM, report their findings in the May issue of the journal Fertility and Sterility.
+Their study, of nearly 2,000 couples undergoing fertility treatment, found that pregnancy attempts were 70% more likely to fail when the man was age 40 or older than if he were younger than 30, regardless of his wife's age. 
+"As an increasing number of couples choose to postpone child-bearing, they should be informed that paternal age over 40 years is an important risk factor for failure to conceive," say de La Rochebrochard and team.
+Because all the women in the study were completely sterile and undergoing in vitro fertilisation (IVF), the age of the fathers was key. 
+And while past studies have suggested that older men are less likely to father children, the extent to which this was related to biological changes or to decreased sexual activity has been unclear. 
+"Our results provide, for the first time, strong evidence for a paternal age effect on failure to conceive that is linked only to biological male ageing," the researchers say. 
+According to the researchers, the lower IVF success rate among relatively older men may be due to poorer-quality sperm. 
+It has long been known that women are less likely to conceive after the age of 35 than before, say the researchers
+But the current findings, they say, suggest that for men, the age of 40 is similarly important.
+"In reproduction," the researchers conclude, "age must no longer be considered as the concern of the woman, but as that of the couple."
+
+The new research supports the idea that there's more to heredity than DNA
+Genetic instructions can be carried from one generation to the next in RNA, a mouse experiment by French researchers suggests.
+Dr Minoo Rassoulzadegan, of the University of Nice Sophia Antipolis, and team report their findings in today's issue of the journal Nature.
+"This is the first demonstration of RNA-induced transmission of heredity," Rassoulzadegan says.
+RNA, or ribonucleic acid, is a single-strand molecule that plays a key role in making proteins in animals by transferring and translating genetic information encoded in DNA.
+But Rassoulzadegan and team have now found that it is capable of much more.
+Spotty mutant mice surprise scientists
+They engineered laboratory mice to have a variation in a gene called Kit. The variation gave the mice white spots on their tails. 
+The mice concerned had a mutant version and a normal version in the two copies of their Kit gene.
+The researchers crossed these heterozygous mice and examined the offspring.
+Some of the offspring had both copies of the normal Kit genes, yet, remarkably, they also had the white spots. 
+The researchers also found that the white spots were transmitted to the next generation of mice, even though these rodents also had the normal genes. 
+A challenge to Mendel's laws
+The findings challenge the laws of inheritance, set down in the 19th century by Austrian monk Gregor Mendel. According to these, offspring can only get the genetic code exactly as it is handed on from their parents. 
+By all rights, if the mice both had normal Kit genes, their tails should have been reassuringly spotless. 
+Rassoulzadegan suggests the answer to this mystery lies in RNA. 
+The mutant version of Kit produces unexpectedly large numbers of aberrantly-sized "messenger" RNA, she found. 
+In addition, the sperm of mutant mice also, surprisingly, was found to have accumulations of RNA. 
+Intrigued by this, her team injected RNA from mutant cells into normal embryos and, presto, spotted-tail mice were born.
+RNA carried in sperm acts as gene silencer
+The hypothesis is that RNA is carried in the mouse's sperm, and at fertilisation it "silences" the activity of the normal Kit gene. This happens not only in the offspring but in subsequent generations too.
+Back in 1956, an American biologist called R. Alexander Brink became the first to suggest "paramutation", in which an order issued by one set of genes was remembered in ensuing generations, even though the gene itself was not subsequently handed on in reproduction.
+But the phenomenon has only been seen in lab plants, not in mammals. In addition, it occurs only very rarely, apparently as a result of interaction between the two copies of a gene. Normally, the pair of genes operate independently. 
+Caution urged before rewriting rule book
+In a commentary on Rassoulzadegan's research, also carried in  Nature, Dr Paul Soloway of Cornell University, New York, stresses caution, saying that her findings have to be replicated by others before Mendel's rule book has to be rewritten. 
+And, he says, the mechanism by which the transmitted RNA works remains unclear. 
+But if the work is validated, the way is open for a rethink on how RNA could influence the transmision of heredity diseases, metabolism and even types of "imprinted" behaviour from distant generations.
+
+Scientists have found the centre in the brain that controls your ability to wiggle your ears
+Human ears can wiggle as well as produce their own sounds, and now researchers have a better understanding of how these unusual processes work.
+Since ear wiggling involves complex coordination of facial muscles, research on it could shed light on related disorders, such as Bell's palsy, which can cause facial paralysis.
+The research into sounds made by the ear, meanwhile, is surprisingly illuminating when it comes to gender and sexuality issues.
+It turns out heterosexual men and women and homosexual women appear to produce different levels of ear noise.
+Ear wiggling
+While most of us produce sound from our ears, the ability to wiggle them in a controlled and detectable way is not as common.
+"The mechanism behind ear movements is sophisticated," says Bastiaan ter Meulen, who led the ear wiggling study, accepted for publication in the journal Clinical Neurophysiology.
+Unlike other facial muscles, ear muscles have their own accessory nucleus, a control area for muscle function, in the brainstem, says ter Meulen, a researcher at Erasmus MC, a university medical centre in Rotterdam, the Netherlands.
+"Compared to animals, especially bats and cats, this nucleus is rather small in humans," he says.
+He says that a muscle involved in eye movement also directly controls ear motion. That's why when we look left or right, our ears slightly withdraw on both sides.
+Breathing and swallowing are also linked to ear movement through muscles and neuronal pathways.
+Ter Meulen and team made these determinations after conducting an EEG, or brain wave test, on a 43-year-old woman who lost consciousness and experienced rhythmic bursts of ear movement.
+Their study marks the first time such ear muscle activity has ever been documented in an EEG.
+Noisy ears
+Another team of researchers analysed noises made by the inner ear that are like echoes that occur in response to clicks, such as pencil tapping, or distortion, such as a bad radio signal.
+Dr Dennis McFadden, a professor of psychology at the  University of Texas at Austin, and his colleagues, measured the strength of these otoacoustic emissions, or ear-produced sounds, in rhesus monkeys and spotted hyenas. 
+Their studies have been accepted for publication in the journal Hormones and Behavior.
+The scientists found that, as for humans, the sounds were stronger in females. During the breeding season, the differences between the male and female ear sounds became even more pronounced, suggesting that hormones affect the emissions.
+Because male and female spotted hyenas are more androgynous when young, the researchers expected that their otoacoustic emissions would be similar. 
+As predicted, measurements of the echo-like ear sounds obtained from nine male and seven female hyenas were similar.
+Sexual orientation factor
+In a prior study, McFadden found that the sounds produced in the inner ears of homosexual and bisexual women were weaker than those emitted from the ears of heterosexual women.
+Since men also exhibit weaker echo-like sounds in the inner ear, MdFadden says the results suggest the inner ear and some unknown brain structures may play a role in sexual preference.
+"The inner ear may be a valuable non-invasive window into events that occur during brain development and sexual differentiation," he says.
+
+Researchers used chimp poop to confirm the origin of HIV
+The closest viral relative to HIV has been traced, for the first time, to wild chimpanzees, confirming the theory that these creatures are the original source of AIDS.
+A team led by Dr Beatrice Hahn of the University of Alabama at Birmingham report their study of wild chimpanzees from southern Cameroon, in today's issue the journal Science.
+"It says that the chimpanzee group that gave rise to HIV ... this chimp community resides in Cameroon," says Hahn, who has been studying the genetic origin of HIV for years.
+In people, HIV leads to AIDS but chimps have a version called simian immune deficiency virus (SIV) that causes them no harm. 
+To date SIV has been found in captive chimps but Hahn wanted to show it could be found in the wild, too.
+Her international team got the cooperation of the government in Cameroon and they hired skilled trackers to locate the elusive chimps.
+"It is hard to track them," says Hahn. 
+But the trackers managed to collect 599 samples of droppings from the chimpanzee subspecies Pan troglodytes troglodytes.
+Hahn's lab found viral DNA and evidence of the virus itself in the droppings and estimated the prevalence of SIV infection in the associated chimp populations.
+"We went to 10 field sites and we found evidence of infection in five," Hahn says.
+"We were able to identify a total of 16 infected chimps and we were able to get viral sequences from all of them."
+Widespread infection
+Up to 35% of the apes in some communities were infected with SIV and different varieties or "clades" of the virus were found. 
+"We found some of the clades were really, really very closely related to the human virus and others were not," says Hahn. 
+She says chimps separated by a river were infected with different clades,
+And a river may have carried the virus into the human population. 
+Cameroon not the origin of the epidemic
+While SIV has been found in Cameroon the epidemic is known to have originated elsewhere.
+"The epidemic took off in Kinshasa, in Brazzaville," says Hahn.
+Kinshasa is in the Democratic Republic of Congo, formerly Zaire, and faces Brazzaville, in Congo, across the Congo River. 
+Studies have traced HIV to a man who gave a blood sample in 1959 in Kinshasa, then called Leopoldville.
+"So how do you get from southern Cameroon to the Democratic Republic of Congo?" Hahn asks. 
+"Some human must have done so. There is a river that goes from that southeastern corner of Cameroon down to the Congo river." 
+Ivory and hardwood traders used the Sangha River in the 1930s, when the original human-to-human transmission is believed to have happened. 
+Transmission still a mystery
+Hahn's study suggests the virus passed from chimpanzees to people more than once. 
+"We don't really know how these transmissions occurred," Hahn says. 
+"We know that you don't get it from petting a chimp, or from a toilet seat, just like you can't get HIV from a toilet seat," she says.
+"It requires exposure to infected blood and infected body fluids. So if you get bitten by an angry chimp while you are hunting it, that could do it." 
+Hahn and team's study only applies to the HIV group M, which is the main strain of the virus responsible for the AIDS pandemic. 
+"It is quite possible that still other [chimpanzee SIV] lineages exist that could pose risks for human infection and prove problematic for HIV diagnostics and vaccines," Hahn and team say. 
+AIDS was only identified 25 years ago. HIV now infects 40 million people around the world and has killed 25 million. 
+Spread via blood, sexual contact and from mother to child during birth or breast-feeding, there is no vaccine against HIV although drug cocktails can help control it.
+
+Should the tropics move another two or three degrees poleward the Sahara Desert could shift perhaps several hundred kilometres towards the poles, the researchers say
+The tropical regions of the world have been expanding since 1979, say US climatologists, who say it is unclear whether the phenomenon is caused by global warming. 
+Dr Thomas Reichler, a meteorology professor at the University of Utah in Salt Lake City, and colleagues, report their findings in today's issue of the journal Science.
+After analysing satellite temperature data collected between 1979 and 2005, researchers estimate that the tropics has expanded by two degrees of latitude, or 225 kilometres during that period. 
+"It's a big deal," says Reichler. "The tropics may be expanding and getting larger."
+The phenomenon could explain the increase in droughts and decrease in precipitation observed in recent years in the subtropical regions of southwestern United States and Europe's Mediterranean basin, the scientists say.
+"The possible expansion of the tropics may be a totally new aspect of climate change," Reichler says. "We don't know for sure what triggered it." 
+Besides global warming, another possible cause is the depletion of the stratospheric ozone layer due to pollutants such as refrigerant gases.
+Jet streams play a key role
+Meteorologists generally consider that the tropics lies between 30&deg;N and 30&deg;S.
+Reichler and team found that in both hemispheres at these mid-latitudes, the lower atmosphere, or troposphere, has became warmer compared to other latitudes in the past 26 years, while the stratosphere has become cooler.
+The researchers argue this change would have pushed each of the tropospheric jet streams - fast-moving wind currents that propel weather patterns - towards the poles.
+"The jet streams mark the edge of the tropics, so if they are moving poleward that means the tropics are getting wider," says study co-author Dr John Wallace, an atmospheric sciences professor at the University of Washington in Seattle.
+He says movement of the jet streams will have long-term impact on rainfall.
+Should the tropics "move another two or three degrees poleward in this century," says Wallace, "very dry areas such as the Sahara Desert could nudge farther toward the pole, perhaps by a few hundred miles." 
+Measurements
+Reichler says the team used long satellite measurements of atmospheric temperatures to find the distinct pattern of warming. 
+Weather balloons also provided independent confirmation of the satellite observation, he says.
+The researchers say the mid-latitude tropospheric warming trend remained even after excluding the record mid-latitude temperatures in 1998, caused by the 1997 El Nino.
+
+Metamaterials could create the ultimate optical illusion: invisibility - although it wouldn't quite look like this
+New materials that can change the way light and other forms of radiation bend around an object may provide a way to make things invisible, say researchers.
+Two separate teams of researchers report in today's issue the journal Science that experimental "metamaterials" could be used to hide an object from visible light, infrared light, microwaves and perhaps even sonar probes.
+Their work suggests that science-fiction portrayals of invisibility, such as the cloaking devices used to hide space ships in Star Trek, might be truly possible. 
+Harry Potter's cloak or The Invisible Man of films and fiction might be a bit harder to emulate, however, because the thing to be made invisible will have to be encased in a thick shell of metamaterials.
+Metamaterials are composite structures that deliberately resemble nothing found in nature. 
+They are engineered to have unusual properties, such as the ability to bend light in unique ways. 
+"The [metamaterial] cloak would act like you've opened up a hole in space," says Dr David R. Smith, a professor of electrical and computer engineering at Duke University in North Carolina and co-author of one of the papers in Science.
+"All light or other electromagnetic waves are swept around the area, guided by the metamaterial to emerge on the other side as if they had passed through an empty volume of space."
+Unlike modern "stealth" bombers that bounce radar off their surfaces so they cannot be seen, an object could be encased in a shell of metamaterials.
+"[It] would create an illusion akin to a mirage," says co-author Dr David Schurig, also of Duke University. 
+Like all physics, the invisibility idea requires a little imagination. 
+"Think of space as a woven cloth," says Shurig. 
+"Imagine making a hole in the cloth by inserting a pointed object between the threads without tearing them." 
+The light, or microwaves, or radar would travel along the threads of the cloth, ending up behind the object without having touched it. 
+"You just need the right set of material properties and you can guide light," Shurig says. 
+Defence project
+The Duke University researchers started working on metamaterials with a grant from the Defense Advanced Research Projects Agency (DARPA). 
+Such materials could provide super-light electronics in aircraft or cars, or highly efficient lenses. 
+The researchers came up with the idea of using these materials to bend light and other electromagnetic radiation. 
+"We are going to try to have an experimental demonstration of these effects. There are a few more steps to go. We are working on these steps," says Smith.
+Shurig says anyone making such a cloak would have to choose what form of radiation one wanted invisibility from. 
+Also, the invisibility would work both ways - a person hidden from the visible light spectrum would have to use infrared or sonar or microwaves to see out, he says. 
+"If want to cover the whole visible spectrum that would a tall order," says Shurig.      
+A second paper in Science, by UK-based professor of theoretical physics, Dr Ulf Leonhardt at the University of St Andrews, also proposes an invisibility device using metamaterials.
+
+Light behaves in weird ways when you shine it through special materials
+Light does something weird when you shift it into reverse, scientists say. It moves faster than the speed of light.
+Two research teams independently reported the counter-intuitive behaviour, observed in two very different experiments, in a recent issue of the journal Science.
+"This is just so mind-boggling that it cries out for attention," says Professor Robert Boyd, an optics expert at the University of Rochester in New York.
+He and his colleagues triggered the odd trick using optical fibre laced with the element erbium, the same kind of fibre used in telecommunications.
+They split a burst of laser light, sending one beam through the optical fibre and allowing the other to travel without interference.
+Oddly enough, the first beam's peak exited the far end of the fibre way ahead of the peak of the comparison pulse.
+Odder still, the exiting peak escaped even before the original peak had entered the fibre.
+What had happened was that as soon as the leading edge of the original pulse entered the fibre, the fibre instantly cloned an identical pulse at the far end. That cloned peak exited before the rest of the original had been introduced.
+At the same time, another cloned pulse fired backward through the fibre to cancel out the original.
+So ultimately, one pulse entered and one emerged, but with timing that appeared to violate light's natural speed limit.
+To test if the pulse was travelling backward as it seemed, the team shortened the fibre a few centimetres at a time and repeated the experiment.
+By adding the experiments together in sequence, they watched the beam's backward progression.
+The fibre itself, they conclude, instantly reconstructed the pulse at the far end, simultaneously sending another pulse backward.
+Not once, but twice
+German researchers made a similar observation in an independent experiment at the Universit&auml;t Karlsruhe. 
+A team led by Gunnar Dolling sent a pulse of light through material whose unusual properties allow it to bend light in unexpected ways.
+Dolling and colleagues also witnessed the very same backward, faster-than-light behaviour as the Rochester team.
+"The propagation of [light] waves through dispersive media often leads to surprising or counterintuitive behaviour," report Dolling and colleagues, referring to dispersion as the ability of a material to separate light into different wavelengths, or colours.
+These and other experiments with weird light are suddenly possible because of new light-dispersive materials, more sensitive technology to detect what light is doing, and because optics researchers are simply paying more attention to the strange things light does in odd materials.
+"Up until several years ago people were not familiar with the concepts of slow and fast light," says Boyd.
+
+Forensic jigsaw puzzle: fungi are helping scientists to estimate the time of death
+Deceased individuals supposedly 'push up daisies', but a new study suggests human cadavers are more likely to support several species of white and yellow fungi.
+The study is the first to describe in detail species of fungi obtained from human corpses. 
+In the future, forensics experts may use the information during criminal investigations to determine when someone died.
+Fungi, parasitic plants that lack chlorophyll, leaves and true roots and stems, often form part of the natural decomposition process that recycles nutrients back into the food chain.
+"The fungi feed on the dead," says lead author Kiyoshi Ishii, whose team's findings are published in the May issue of the journal Legal Medicine.
+Ishii, a biologist at Dokkyo University School of Medicine in Japan, and his colleagues analysed two humans whose bodies were found decomposing in very different environments.
+The first was a corpse discovered lying face down on a concrete floor in an abandoned house.
+Police determined the body belonged to a 72-year-old man who had been missing for 10 months.
+The scientists observed yellow and white fungi on the deceased's chest, abdomen and thighs, but little insect infestation, probably because the house was dry and isolated.
+The second case study involved skeletal remains clad in a shirt and pants found in a forest.
+Forensics specialists determined the body belonged to a 50 to 60-year-old man who had died at least 6 months before the body's discovery. The scientists once again detected yellow and white fungi growing on the corpse.
+Back in the lab
+Ishii and his team collected the fungi and incubated them in a laboratory.
+They identified several species including Gliocladium, a slimy counterpart to penicillin; Eurotium chevalieri, a fungus that can be bright yellow; and E. repens, which is commonly found in soil. The Eurotium species dominated the collected samples.
+Ishii explains that the white and yellow colours are associated with the sexual stages for Eurotium fungi.
+The parasite produces threadlike filaments that terminate with circular, colourful structures called ascomata that are involved in reproduction.
+The fungi also produce colourful conidia, or asexual spores, which tend to form in the morning and germinate in the afternoon and evening.
+Ishii says the environment in which a body lies, rather than the biochemistry of the individual or the manner of death, tends to dictate how much or how little fungi will colonise a cadaver.
+Flies, beetles, fungi
+Yuichi Chigusa, a medical parasitologist and entomologist at Dokkyo Medical University's School of Medicine, says that fly larvae usually infest corpses within an hour to a half-day after the victims' death. They are then followed by Coleoptera (beetles) and fungi.
+He is excited about the potential of fungi for further aiding detective work.
+"I am surprised that fungus is a potential tool for determining post mortem intervals in cadavers without infestation of dipteran larvae and/or beetles," Chigusa says. 
+"Therefore, I think it is very important that forensic pathologists, forensic entomologists and forensic mycologists cooperate in determining post mortem intervals during forensic analysis."
+
+These flat-headed dinosaurs went head-to-head 66 million years ago
+A dragon-like dinosaur named after Harry Potter's alma mater has performed a bit of black magic on its own family tree, say US palaeontologists who unveiled the 'Dragon King of Hogwarts'.
+The newly described horny-headed dinosaur Dracorex hogwartsia lived about 66 million years ago in South Dakota, just a million years short of the extinction of all dinosaurs.
+But its flat, almost storybook-style dragon head has overturned everything palaeontologists thought they knew about the dome-head dinos called pachycephalosaurs.
+"What you knew about pachycephalosaurs, you can chuck it," says Dr Spencer Lucas, curator of palaeontology at the New Mexico Museum of Natural History and Science in Albuquerque.
+"Dracorex hogwartsia is a rather fantastic new dinosaur," affirms palaeontologist Dr Robert Sullivan of the State Museum of Pennsylvania.
+For years dinosaur experts had thought the classic dome-headed, head-butting sorts of pachycephalosaurs evolved from earlier flat-headed ancestors.
+The last thing they expected to find at the end of the Age of Dinosaurs was a dramatically flat-headed pachycerphalosaurs, or pachy.
+"If you were going to predict the kind of dinosaur that would live at that time, it would not be this," says Lucas.
+Without so much as a nod of the head or the waving of a wand, hogwartsia has reversed the pachy family tree.
+"Instead of going from flat-headed to domed, you're going from dome-headed to flat," says Sullivan.
+Along with several colleagues, Sullivan co-authored the first detailed study of the new dinosaur, published recently in the New Mexico Museum of Natural History and Science Bulletin.
+Dracorex hogwartsia, which translates to Dragon King of Hogwarts, was unearthed in 2003 in the Hell Creek Formation of South Dakota by three amateur fossil hunters working with the Children's Museum of Indianapolis. 
+But it wasn't until it was at the museum, while the fossil was being carefully prepared, that renowned dinosaur researcher Dr Robert Bakker happened to catch sight of it while visiting.
+Bakker then recruited pachycerphalosaurs expert Sullivan and other palaeontologists to take a closer look.
+How to name a dinosaur
+But how did it get its name? A group of children at the Children's Museum of Indianapolis drew the connection to the fanciful school of witchcraft that the famous fictional wizard Harry Potter attends and came up with the name hogwartsia.
+"It's a very dragon-like looking dinosaur," says Sullivan.
+J.K. Rowling, author of the Harry Potter series, has been notified and apparently rather likes the new name.
+"I am absolutely thrilled to think that Hogwarts has made a small claw mark upon the fascinating world of dinosaurs," says Rowling in a statement.
+"I happen to know more on the subject of palaeontology than many might credit, because my eldest daughter was Utahraptor-obsessed and I am now living with a passionate Tyrannosaurus rex-lover, aged three.
+"My credibility has soared within my science-loving family, and I am very much looking forward to reading Dr Bakker and his colleague's paper describing 'my' dinosaur."
+
+Exercise seems to put a brake on runaway cell growth, one of the hallmarks of cancer
+The anticancer effects of exercise are due to increases in a protein that blocks cell growth and induces cell death, say Australian researchers.
+This would slow down runaway cell growth, one of the hallmarks of cancer, the researchers suggest.
+But the team, led by Dr Andrew Haydon from Monash Medical School in Melbourne, cannot say how much exercise someone needs to show these effects.
+The researchers publish their results in the May issue of the journal Gut.
+They identified new cases of colorectal cancer in a prospective study of 41,528 adults recruited between 1990 and 1994. 
+They then looked at baseline body mass index, level of physical activity reported and compared baseline levels of two proteins: insulin-like growth factor binding protein-3, or IGFBP-3, and insulin-like growth factor-1, or IGF-1.
+Analyses centered on 443 colon cancer patients followed for more than 5 years. 
+Among subjects who were physically active, an increase in IGFBP-3 was associated with a 48% reduction in colon cancer-specific deaths. There seemed to be no association with IGF-1. 
+For the physically inactive, there was no association between IGF-1 or IGFBP-3 and colon cancer survival.
+The researchers conclude that increased levels of IGFBP-3 with exercise blocks IGF-1's proliferative effect on cell growth.
+IGF-1 has been shown to stimulate cell growth, inhibit cell death, and promote angiogenesis, the formation of new blood vessels, which tumors need to grow. 
+"We did not look at the amount of physical activity needed to reduce colorectal cancer incidence," Haydon points out. 
+"Other studies ... have shown a dose-effect, meaning the more exercise the lower the risk. However, our study did not try to address this issue.
+"We were examining the effect of physical activity on one's prognosis following a diagnosis of bowel cancer and the possible mechanisms behind this effect." 
+For more information about cancer, including fact sheets and where to go for counselling, see the Cancer Council Australia website.
+
+Elephants, snakes and octopus tentacles have inspired a new type of flexible robot
+A robot with a flexible, trunk-like arm could one day work like an elephant to grasp unwieldy loads, say its developers.
+It could also navigate like a snake through the rubble of a disaster zone, or feel around inside the dark crevasses of other planets.
+Conventional robots have rigid joints; picture a crane-like appendage with a claw-shaped hand.
+But the OctArm's nimble design allows it to move freely and adapt to its surroundings.
+"These robots are invertebrate robots and are good at getting into tight spaces and wriggling around," says Ian Walker, a professor of electrical and computer engineering.
+His team at Clemson University in South Carolina has been working on the project for nearly 10 years.
+Conventional robots work best when given a predictable job in a structured setting, such as a factory assembly line. 
+But in the unpredictable, unstructured environment of a disaster zone or the surface of a distant planet, a more flexible robot is needed.
+Walker and a team of researchers from eight institutions in the US and Israel built a strong, dexterous robotic arm that uses tubes pumped with compressed air to mimic the muscles that control tongues, trunks and tentacles.
+A scientist uses a joystick to the control the OctArm, which resembles an elephant trunk: thick at the base and tapered toward the tip.
+A computer responds to the joystick's motions by changing the air pressure inside individual tubes.
+For example, to move the OctArm from the extended position into a coiled shape, air pressure must be increased in the tubes on the side of the arm facing up.
+Simultaneously, air pressure decreases in the tubes on the downward-facing side of the arm.
+The force of increased air pressure on one side of the arm pulls it into the coiled position. To extend it again, the scientists apply air pressure the other way around.
+Curling and lifting
+More complicated motions, such as curling around an object and lifting, require more sophisticated computer algorithms. Developing these algorithms is one of the bigger challenges facing Walker and his team.
+In field tests, the OctArm successfully grasped balls and pieces of wood, even clinging to them, while submerged in rushing water.
+"The OctArms are not precise or positional, but they are compliant and flexible and can conform to crazy shapes and do some things that traditional robots can't," says Shane Farritor, associate professor of mechanical engineering at the University of Nebraska-Lincoln.
+Later this year, Walker and his team will be working to improve the OctArm's precision, adding sensors and a camera.
+
+Chances are, you'll feel good about life-defining events when you look back on them
+When we remember events that helped to shape our identity, such as a break-up or marriage, we tend to downplay the fear, anger or other negative emotions and remember more of the positive ones, a new study indicates. 
+"These findings suggest that healthy individuals work to build a positive narrative identity that will yield an overall optimistic tone to the most important recalled events from their lives," write study authors Drs Michael Conway and Wendy-Jo Wood of Concordia University in Montreal, Quebec. 
+The findings, published in the latest issue of the Journal of Personality, may also have implications for someone's mental health. 
+"Mental health is maintained or improved by people's attempts to make sense of their life experiences," Conway says. 
+"People try to see the positive in even very difficult life experiences, and come to downplay, as much as they can, how negative some events were in the past," he explains. 
+For their research, Conway and Wood investigated people's emotional memories for self-defining events, which they described as emotionally complex events that contribute to a person's sense of identity or overall life story. 
+In one study, 279 university students were asked to think about an important past event that helped define themselves.
+They were then asked to describe the event in various terms, including the extent to which it had a big impact on them and how much it helped them learn about themselves and about life. 
+Based on the students' responses, Conway and Wood conclude that a person's perception of the impact of an event is a good marker for meaning making, that is the process that results in an individual integrating an event with his or her positive sense of identity. 
+In a second study, 79 university students were asked to report and describe, on paper, five self-defining memories and to rate those events on a five-point scale in terms of its impact.
+They also completed two questionnaires about the 10 emotions they felt when the event occurred and how they currently felt about the event, respectively. 
+Happiness and pride
+Conway and Wood found that when the study participants reflected on negative events, such as conflict with bosses or teachers, death, or physical or sexual assault, they reported that they currently felt less negative emotions, like anger and disgust, and more happiness and pride than they had felt at the time of the event. 
+And when the students reflected on positive events, like a dating relationship or marriage, recreation, or attaining a personal goal, they reported feeling just as happy as they had felt at the time of the event, as well as similarly intense feelings of love and pride.
+Again, however, they also reported feeling less anger, embarrassment, guilt and other negative emotions than they had initially felt. 
+"What was striking is that the findings held up for a wide range of emotions," Conway says, adding that "when making sense of their past experiences, people would downplay all the negative types of feelings they had, such as fear and anger". 
+Death in the family
+How does this relate to a negative event like the death of a grandmother, for example?
+"The sad event is still mostly sad," Conway says. "But the positive emotions have come out more."
+People are "seeing the silver lining, so to speak" and may feel happy afterwards as they realise that the grandmother's suffering is over, he says. 
+Conway says how the practice is common among men and women in a variety of life situations.
+"Everyone can experience strong emotional reactions in extreme situations, and everyone needs to come to terms with such events in order to maintain a positive sense of self, and a positive sense of the world at large."
+
+Bacteria found in household sewage can generate their own electricity. Now scientists say they are one step closer to harnessing it
+The waste water we flush down the loo could one day be used to generate electricity, scientists from Belgium say. 
+The Ghent University researchers have designed a way to boost the output of microbial fuel cells, an emerging technology that captures the energy produced when bacteria break down waste and turn it into electrical current.
+Investigators from around the world are researching the potential of microbial fuel cells, but prototypes so far have only produced tiny amounts of electricity. 
+"At the moment we are still at the stage of basic research, but the potential for the technology is good," says Associate Professor Zhiguo Yuan, from the Advanced Wastewater Management Centre at Australia's University of Queensland. 
+The latest paper, which appears in the journal Environmental Science and Technology, brings the concept closer to reality.
+The researchers show that six small fuel cells stacked together can generate higher voltages and increased current.
+"The efficiency of these systems is determined by the distances the electrons have to travel," says co-author Dr Korneel Rabaey.
+"If you want to generate a lot of power from microbial fuel cells, you have to have a very thin reactor. But you also need to be able to work with a high volume of waste water." 
+Putting several small cells together ticks both of those boxes, says Rabaey, who moved to the University of Queensland a month ago. "This work shows one step we need to make larger scale designs." 
+But scientists aren't sure exactly which bugs generate the electricity in the fuel cells.
+"There is a mixture of those that can live in that environment," says Yuan.
+Treating water
+Scientists are most interested in using microbe-generated electricity to power the water treatment process itself.
+As well as producing current, the technology can also help clear bacteria out of the water. It might also clean out substances like sulfur and nitrogen.
+Once scientists figure out how to build large-scale fuel cells, Rabaey says, the cells will probably be used first to treat industrial waste water.
+The idea of using stuff we flush down the toilet to power our light bulbs is probably a more distant hope. But he says it is not out of the question.
+"The amount of energy that is in waste is incredible," he says. "Just one sugar-cube, for example, has enough energy to power a laptop for 12 hours. And the stuff in our waste water is just different forms of sugar."
+
+Locusts reach a critical point when they 'know' when to swarm
+Like an army preparing for battle, locusts instinctively wait until their 'battalion' is large enough before falling into line and swarming ahead en masse, researchers find.
+The apparently leaderless group will fly around chaotically until the swarm reaches a certain density of numbers, when they immediately assemble and become an orderly, collective plague.
+Researchers led by Dr Jerome Buhl from Australia's University of Sydney have pinpointed this exact point of change, called the tipping point, by using statistical physics models of disordered and ordered particles.
+The international team publishes its findings today in the journal Science.
+The researchers assembled a circular perspex 'arena' shaped liked a Mexican hat in the laboratory.
+Locusts were then released into the arena and their movements filmed as more and more locusts were added to the group.
+The team found that at a low density of insects, the locusts swarmed around chaotically.
+At intermediate density the locusts banded together but changed their marching directions quickly.
+But when enough insects were released into the arena to reach the critical tipping point - 20 insects per square metre - the group immediately massed together and swarmed as one in a persistent direction.
+Co-author Professor Steve Simpson from the University of Sydney says the statistical physics models of disordered and ordered particles used in the experiment are like dodgem cars racing around an arena.
+"You give these dodgem cars a set of simple local rules. If somebody drives past them they must move and follow next to them. If they see a dodgem car a little further away then they must move towards them. If they get too close to another dodgem car they must bounce away from it," he says.
+"If you scale that up to a whole bunch of dodgem cars, or particles, or locusts then as you start to add more and more to the arena, or environment, you suddenly get to a number where they all start moving in the same direction together."
+Buhl says the laboratory findings reflect similar findings in the field.
+He says the research, which was carried out with UK, US and Canadian researchers, could be useful in controlling pest outbreaks that devastate crops and bring disease.
+
+The new test is based on a stain that detects the protein keratin. Vaginal cells, seen here, don't express the protein, giving a characteristic yellow colour. But skin cells and some mouth cells do, so they stain magenta and red
+A new forensic technique that tells scientists which cells come from which parts of the body could help solve sex crimes, its developers say.
+A New Zealand PhD student has found a simple way of identifying whether cell samples collected for DNA testing come from the skin, mouth or vagina.
+"All it really involves is a couple of stains and some microscope slides of the cell samples and you get some lovely different coloured cells," says Claire French, from the University of Auckland.
+Currently, DNA from cells found at a crime scene can link a person to the crime but cannot provide evidence about which part of the body the cells came from.
+The technique French has developed involves staining epithelial cells, the outer layer of body surfaces and organs, which are easily shed or secreted.
+The stain reveals different colours, corresponding to the presence of the protein keratin.
+Skin cells express keratin and stain magenta; vaginal cells don't express keratin and stain orange; and cells in the mouth vary depending on their location, and stain red.
+Sue Vintiner, a forensic scientist with New Zealand's Environmental Science and Research (ESR), says the technology could have practical applications.
+"I've been involved in cases where we've been unable to scientifically prove that an object ... has been used to violate someone in a sexual assault or whether it was just touched by the alleged victim," she says. "Claire's work could change that."
+Its developers say the technology could be used to develop a portable, histological staining kit for routine use at crime scenes and in forensic laboratories.
+The research, which will soon be presented at the European Academy of Forensic Sciences conference, has received strong support from the New Zealand Police.
+Claire's findings have also earned her New Zealand's McDiarmid Young Scientist of the Year Award.
+The intellectual property underpinning the research has been jointly protected by ESR and the University of Auckland.
+
+Poison ivy, a species introduced to Australia and now a weed, will grow faster and become more poisonous with increased CO2 levels
+Add another item to the list of health threats posed by global warming: poison ivy that's more poisonous, and lots more of it. 
+When scientists increased CO2 to the levels expected to be seen at the middle of this century, poison ivy (Toxicodendron radicans) grew more than twice as fast.
+The plants also produced more of a type of urushiol, the substance that causes an allergic reaction, the researchers report online in the Proceedings of the National Academy of Sciences. 
+"This is bad news for those of us who suffer from poison ivy," says lead author Dr Jacqueline Mohan of the Marine Biological Laboratory in Woods Hole, Massachusetts.
+Mohan and her team studied plots of a forested area surrounded by PVC pipes that pumped out CO2, allowing them evaluate the effects of the greenhouse gas in a real-life forest environment.
+They compared poison ivy growth over a six-year period in three CO2-enriched areas and three areas with normal air. 
+Under the high-CO2 conditions, the poison ivy plants grew 150% faster every year than the control plants. The plants also contained 153% more of the urushiol compound that causes an allergic reaction.
+More than 80% of the world's population will develop an itchy rash if exposed to poison ivy. 
+Over the past two decades, Mohan notes, scientists have observed increased worldwide growth in vines, which is in some cases choking out the regrowth of trees.
+Vines benefit from extra CO2, she explains, as the gas fuels photosynthesis. Unlike trees, vines have to devote relatively little energy to growing wood, and can instead pump the extra photosynthesis energy into leaf production.
+
+A seed bank, to be built in the Artic, will be essential to protect future agriculture, its proponents say
+A frozen Noah's Ark to safeguard the world's crop seeds from disasters will be built on a remote Arctic island off Norway, the Norwegian government says.
+Construction of the Global Seed Vault, in a mountainside on the island of Svalbard 1000 kilometres from the North Pole, would start in June with completion due in September 2007.
+"Norway will by this contribute to the global system for ensuring the diversity of food plants. A Noah's Ark on Svalbard if you will," says Norwegian Agriculture and Food Minister Terje Riis-Johansen.
+The doomsday vault would be built near Longyaerbyen, Svalbard's main village, with space for three million seed varieties.
+It would store seeds including rice, wheat, and barley as well as fruits and vegetables. 
+It would be a remote Arctic back-up for scores of other seed banks around the world, which may be more vulnerable to risks ranging from nuclear war to mundane power failures. 
+"Gene banks can be affected by shutdowns, natural disasters, wars or simply a lack of money," Riis-Johansen says. 
+Loss of genetic diversity would mean losing a part of cultural heritage.
+"We also reduce the ability of agriculture to meet new challenges relating to climate change, population increase, and so on," he says. 
+The seeds would be stored at -18&deg;C. If the power fails, the seeds will probably stay frozen. 
+"The temperature there is around -3&deg;C, -4&deg;C in the summer but we believe that even if the freezers broke down a suitable temperature would last for months," says Grethe Helene Evjen, a senior adviser at the agriculture ministry. 
+"This will be primarily a duplicate storage for plant seeds already stored elsewhere," she says.
+Seeds would remain the property of nations making deposits. 
+Norway would provide 30 million Norwegian crowns (U$4.94 million) to build the vault. 
+Norway has long talked of building the Arctic seed vault without previously taking action.
+For about 15 years some varieties of seed have been stored in a disused Svalbard mine under a plan to see if they can germinate after 100 years. 
+Norway has worked with the UN Food and Agriculture Organization on the plans.
+It would also get financial support from the Global Crop Diversity Trust to help poor countries use the storage.
+
+Is technology a match for evolution? And does this mean that modern humans are still evolving?
+New evidence that the hobbit made the stone tools found alongside it might be evidence that humans are still evolving, says an Australian researcher.
+The use of technology doesn't mean we have outwitted evolutionary selection pressures, says Dr Mark Moore, an expert on ancient stone flaking technology at the University of New England.
+He made the comments in light of research published in today's issue of the journal Nature on how early hominids used tools on the Indonesian island of Flores.
+Some scientists have recently argued that the tools found alongside the hobbit at the Liang Bua cave are too complex to have been made by anyone but modern humans.
+But Moore, along with Australian and Indonesian colleagues, think otherwise.
+The team analysed the techniques used to make over 500 tools found at Mata Menge, a site about 50 kilometres from where the hobbit was found.
+The researchers say although the tools would have been made 700,000 years before the hobbit was around, they seemed just as complex as the ones found alongside it.
+The researchers say the tools were probably made by ancestors of Homo floresiensis, suggesting a long history of toolmaking on the island.
+This supports the idea that the hobbit, even with its small brain, was capable of making the tools found alongside it, says Moore.
+He previously reported that such tools could be made without the degree of forethought usually associated with modern humans.
+"The techniques used to make [the tools] aren't quite as sophisticated as a lot of archaeologists would have you believe," says Moore.
+"They are certainly within the capabilities of a small-brained hominid."
+Implications for evolution
+Those who discovered the hobbit believe it evolved from a larger bodied, larger brained ancestor that shrank over time as it was isolated on the island.
+The fact that the hominid could still make stone tools despite its shrinking brain suggests toolmaking was key to survival on the island.
+This supports the argument that technology helps humans survive changing environments. 
+But Moore thinks it also tells us that technology doesn't protect us from evolutionary selection pressures, like predators or other environmental factors that affect our survival.
+The environment is a bigger force than we give it credit for, he says.
+"There's an underlying assumption in the popular media, in particular, and amongst some scientists, that since we adapt to our environment through technology that somehow this is buffering us from the forces of natural selection," says Moore.
+But, he says, the use of technology by the hobbit's ancestors to adapt to their environment did not stop them from shrinking in response to selection pressures.
+"Even thought they had a technological adaptation to the environment it didn't mean that they had stopped evolving," says Moore. "They clearly had continued evolving. Technology was not able to stop that from happening."
+He says this could be relevant to current debates over whether modern humans are evolving.
+"We are so surrounded by technology every day," says Moore. "But that doesn't necessarily mean that the environment isn't also having an effect."
+
+Saturn's moon Enceladus might have rolled or rotated itself to place an area of low density at the south pole. This illustrates the moon's interior, with warm, low-density material rising to the surface (yellow) from within or from its rocky core (red)
+Millions of years ago, Saturn's moon Enceladus may have somersaulted in space, creating an ice-spewing hot spot on the moon's south pole, scientists suggest.
+For now, it is the only explanation why the small satellite sports a very active, though isolated, polar region.
+Dr Francis Nimmo, an assistant professor at the University of California at Santa Cruz, and team publish their research today in the journal Nature.
+During flybys of Enceladus, the Saturn-orbiting Cassini probe has snapped pictures of gigantic icy plumes, indicating active geysers at the moon's south pole.
+Researchers who have been studying images and other data collected by the Cassini spacecraft believe a relatively warm blob of ice rose from beneath the moon's frozen surface.
+It could also have emerged from within its frigid and rocky core.
+Less dense than the surrounding terrain, the blob would be more susceptible to Saturn's powerful gravitational tug on Enceladus, a grip that at one time seems to have caused the moon to roll over, says Nimmo.
+The team calculated the effects of a low-density blob beneath the surface of Enceladus and showed it could cause the moon to roll over by up to 30&deg; and put the blob at the pole.
+It may not have been a solitary incident either, Nimmo says.
+"It could be like a lava lamp and each time a blob is reproduced, it causes the moon to flip," he says.
+The manoeuver may not be all that uncommon. Studies of magnetically charged particles around Earth show evidence that the planet's north pole may at one time have resided elsewhere, Nimmo adds.
+Likewise, Uranus's moon Miranda shows evidence of multiple flips, he says.
+The researchers plan follow-up studies to look for more evidence. 
+First, they want to carefully examine surface images for craters. The moon should be more heavily cratered in the areas that face its direction of travel.
+If Enceladus flipped, it's current face should show fewer impacts than its trailing regions, which at one time may have been facing forward.
+The pull of gravity
+The team also would like to fly Cassini low over Enceladus' southern pole to see if its gravitational pull is slightly weaker than at other parts of the moon. 
+Cassini would become the test object while radio antennas on Earth track its movement during the flyby.
+A minute change in Cassini's speed, perhaps as small as a centimetre per second, would be an indication of a lower-mass region at the pole.
+"It's a difficult measurement to make, but we'd like to try," Nimmo says.
+Scientists are not sure what mechanism fuels Enceladus' hot spot, but they believe it is tied to tidal forces from Saturn and possibly a sister moon, Janus.
+"You have this tiny moon blasting out a huge amount of heat," Nimmo says. "Presumably it has to get squeezed. Something is causing all this pushing and pulling.
+"It's astounding that Cassini found a region of current geological activity on an icy moon that we would expect to be frigidly cold, especially down at this moon's equivalent of Antarctica," adds co-author Dr Robert Pappalardo, a planetary scientist and assistant professor at NASA's Jet Propulsion Laboratory.
+
+It took just 10 million years for the Artic Ocean to go from bath-temperature to frigid
+Dramatic shifts in Earth's climate system drove the sea at the North Pole from sub-tropical temperatures to icy chill in the relatively brief span of 10 million years, according to a series of studies.
+The papers report a mission in which European scientists aboard a ship braved flowing walls of ice to delve deep into the Lomonosov ridge on the floor of the Arctic Ocean. 
+The precious cores of sediment, retrieved from up to 430 metres below the seabed, give an idea of the planet's climate going back 55 million years thanks to the fossilised creatures, plants and stones buried in them. 
+This surveyed period kicks off with an astonishingly warm period called the Palaeocene-Eocene thermal maximum. At one point during this era, the Arctic Ocean was 23&deg;C.
+Then, around 49 million years ago, large volumes of cool freshwater for some reason were dumped into the Arctic, chilling the sea to around 10&deg;C and diluting its saltiness so much that in summer months, a species of green freshwater fern covered much of its surface. 
+At 45 million years ago, the first ice started to form, as evidenced by pebbles dropped by icebergs, and the relative cooling has continued to the modern era. 
+The studies, published today the journal Nature, were carried out in an initiative called Arctic Coring Expedition.
+A Swedish-flagged, Norwegian-operated drillship, the Vidar Viking, manoeuvred in water 1000 metres deep just 238 kilometres from the North Pole, protected by a Russian and a Swedish icebreaker.
+"At times, the drill site was covered with ice 2-3 metres thick," says one of the lead authors, Jan Blackman, a professor at Stockholm University. 
+"We encountered an icefloe of multi-year ice, harder and denser than ice from just one Arctic winter. It was like driving into a brick wall." 
+Natural shifts in climate
+In a history spanning some 4.5 billion years, Earth has gone through natural shifts in climate change. 
+The drivers for this include changes in solar radiation, surges in volcanic activity, releases of methane stored underground, shifts in vegetation and the light that is reflected back into space by polar icecaps. 
+The study delves into the distant past and does not cover recent history, especially the Industrial Revolution, whose fossil-fuel emissions many blame for global warming. 
+Evidence has accumulated in recent years that Arctic ice cover is thinning and shrinking in response to this warming, which in turn may have a big impact on polar bears and other species. 
+The icecap at the North Pole floats on the Arctic Ocean, which means its melting does not affect global sea levels. 
+In Antarctica, it lies mainly on rock, which means that even a partial melting would threaten coastal cities and deltas around the world.
+
+Bushfire smoke hangs over Sydney 
+Climate change could lead to a 20% increase in the area burned by bushfire in Sydney by the middle of this century, Australian research shows.
+This does not necessarily mean new land will be affected. The increase may instead be due to some areas being burnt more frequently.
+Fire ecologist, Professor Ross Bradstock, of the University of Wollongong will report his findings at the  Australasian Bushfire Conference 2006 in Brisbane next week.
+Sydney's changing fire regime is important to understand because it's Australia's most populated city, says Bradstock, which itself increases a city's risk of bushfires.
+Sydney is also ringed by fire-prone vegetation, and has a fire-friendly climate and layout. For instance, a lot of the city is in the path of fire-bearing winds.
+"It's the biggest fire game in the country," says Bradstock.
+In the past 20 years, around a million hectares of Sydney's have been burned by bushfire, including areas in the Greater Blue Mountains World Heritage Area.
+And research published earlier this year suggests Sydney's fire risk is getting worse, says Bradstock.
+Researchers at CSIRO and the Bureau of Meteorology analysed climate change models and predicted by 2050 there would be a 5-12% increase in the number of days with a high, very high or extreme fire danger. 
+"That means an increase in the chance of having conditions which are conducive to major fires," says Bradstock.
+Major fires, those that burn 1000 hectares or more, are only a minor proportion of the total number of fires but account for 95% of the area burned, he says.
+Shift in fire weather
+Bradstock wanted to find out how this shift in fire weather would translate in terms of the actual increase in number of fires and the area burnt.
+To do this, he developed a model that combined the CSIRO and meteorology bureau predictions with historical records of fires from the Blue Mountains area to the west and the Central Coast area to the north of Sydney.
+The models show the relationship between worsening fire weather and number of major fires is not linear.
+Bradstock says the models show that while a 5% increase in high-risk days would result in a 2-6% increase in the area burned, a 12% increase in high-risk days would result in a 15-20% increase in area burned.
+Over the 20 years between 2050 and 2070, he says this would equate to up to 150,000 more hectares than was burned over the past 20 years.
+Bradstock says the Central Coast area is most vulnerable because it has a hotter and drier environment and a greater density of people living close to bushland.
+This is the first time such an approach has been used in Australia and can be transferred to other locations, says Bradstock.
+He developed the model in his previous job at the New South Wales Department of Environment and Conservation.
+
+Where people live will have a big impact on how technology will affect their lives, says a new report that highlights the technological divide
+Australia is among countries that will gain the most from technology by 2020, a study finds. But poorer countries look to miss out.
+The RAND Corporation study finds that it is countries that are already on technology's cutting edge, not those that are currently lagging in technological advances, which will benefit the most.
+"Where people live will have a big impact on how technology applications affect their personal health and standard of living, and will also play a part in determining the ability of their countries to protect them and their environment," says Dr Richard Silberglitt, one of the lead authors. 
+The study looked at 29 countries that were ranked as technologically advanced, proficient, developing or lagging.
+"People in the US and Canada, Germany [representing western Europe], South Korea and Japan, Australia and Israel will benefit the most from advances in technology, and they will be able to exploit technology regardless of its sophistication," the report concludes.
+As examples of potential high-tech advances, it cites growing tissue to implant and replace human body parts; creating pervasive sensor networks in public areas to conduct real-time surveillance; providing access to information any time and anywhere; and creating wearable computers. 
+"China, India, Russia and others ... such as Poland [representing eastern Europe] could also make significant advances, along with simpler ones," the report says of what it describes as scientifically proficient countries.
+These countries could, for example, "provide their people with drug therapies that preferentially attack specific tumors or pathogens ... [and] vastly improved medical diagnostic and surgical procedures". 
+Scientifically developing countries "Mexico, Turkey, Brazil, Colombia, Indonesia, South Africa and Chile ... are poised to take advantage of modestly sophisticated technology applications including devices to constantly track the movement of everything from products to people; easy-to-use health diagnostic tests that give immediate results for a large range of infections; and environmentally friendly manufacturing methods," the study says. 
+The scientifically lagging countries - Fiji, the Dominican Republic, Georgia, Nepal, Pakistan, Egypt, Iran, Jordan, Kenya, Cameroon and Chad - "are burdened by problem-plagued political systems, a lack or resources or infrastructure, and class disparities," the study says. 
+"When such countries have the will to make changes ... they can improve the lives of their citizens," the study adds, citing examples such as cheap solar energy for remote or portable applications, ways to purify water that won't require major infrastructure, and rural wireless communications. 
+China and India lead the group of scientifically proficient, the study adds. 
+"Yet they need to continue making progress in financial institutions, legal and policy issues rural infrastructure, environmental protection, research and development investments, rural education and literacy, and governance and stability if they are to advance," it says.
+
+The Itokawa asteroid is made up of loosely packed bits of sand and boulders
+A Japanese spacecraft that landed on an asteroid found a ball of rubble held loosely together by its own gravity, unlike other asteroids that have been visited, reports say.
+The spacecraft Hayabusa, whose name means 'falcon' in Japanese, hovered over the near-Earth asteroid Itokawa last year, taking several measurements before landing briefly on the orbiting gravel pile. 
+Itokawa has two parts resembling the head and body of a sea otter, according to Professor Akira Fujiwara of the Japan Aerospace Exploration Agency and his colleagues in today's issue of the journal Science. 
+Previously studied asteroids appear to be lumps of solid rock, but Itokawa is made up of loosely packed bits of sand and boulders, they say. 
+Their findings could have implications for deflecting asteroids that might pass too closely to the Earth in the future. 
+"We've never had a close-up look at such a small asteroid until now," says Dr  Takahiro Hiroi of Brown University in Rhode Island, who worked on the joint US-Japanese study.
+"Large asteroids such as Eros are completely covered with a thick regolith, a blanket of looser material created by space weathering. With Itokawa, we believe we have witnessed a developing stage of the formation of this regolith." 
+Itokawa is very small, just 500 metres long. But it is close, orbiting just 516 million kilometres away from Earth. Although it does not threaten to collide with Earth, it makes a tempting scientific target. 
+Near miss
+Hayabusa very nearly did not make it. 
+The little spacecraft, now bringing a capsule of samples back to Earth, uses an electronic ion propulsion system, whose efficiency should be critical to future missions in deep space. 
+At one point, Hayabusa lost communication with its controllers, writes Associate Professor Erik Asphaug of the University of California, Santa Cruz in a commentary in Science. 
+"Its hydrazine [fuel] had leaked away shortly after the second sample collection attempt. Two of the reaction wheels had failed and the battery was dead. Adding insult to injury, Minerva, intended to be the first asteroid surface robot, had been released during an unexpected manoeuver and was lost to space," he adds. 
+"Yet despite these heartbreaking setbacks, Hayabusa has been a stunning success both for asteroid science and for deep space concept testing." 
+Asphaug says information delivered by the spacecraft "enhances our understanding of near-Earth objects. Near-Earth objects are not only important scientifically, our planet formed from them, but have also become political hot potatoes, given the growing pressure to do something to mitigate the risks they may pose to Earth". 
+The spacecraft, launched in 2003, is expected to glide back to Earth in 2010 and crash-land in the Australian desert.
+
+The search for evidence of a killer meteorite continues
+Remains of what is believed to be a giant Antarctic crater could be evidence of a meteorite that caused Earth's biggest mass extinction and triggered the break up of Gondwana, scientists say. 
+While some experts are excited by the find, not all are convinced this is a crater all, let alone one that came from a 48-kilometre wide meteorite that wiped out most of life on Earth.
+Geophysicist Dr Ralph von Frese of Ohio State University in the US and colleagues are due to report their research at an Antarctic science meeting in Hobart early next month.
+A number of suspected impact craters have been linked to the so-called Great Dying at the end of the Permian 250 million years ago. This was a time when 90% of marine life and 80% of life on land were wiped out.
+But, says von Frese, his is the best candidate for the killer crater.
+First, he says, the circular land features analysed in the Wilkes Land region of East Antarctica, south of Australia, suggest a big enough impact to have caused catastrophic damage to Earth.
+At 480 kilometres wide, the crater would be more than twice the size of the Chicxulub crater, formed from the impact believed to have wiped out the dinosaurs much later, say the researchers.
+Second, says von Frese, evidence, including its location, suggests it is older than 100 million years, the date at which Australia drifted northwards from Gondwana.
+Third, the landform has a special telltale feature of impact craters at its centre, a 320 kilometre wide plug of dense material, says von Frese. This is expected to be mantle material that was sucked up as the meteorite rebounded from the Earth's surface.
+This so-called mascon is a well known feature of craters on the Moon, says von Frese, who studies lunar impact craters.
+And he says no other suspected craters linked to the Permian extinction show this feature.
+Gravity measurements
+Von Frese and team mapped the crater using two different sets of measurements.
+Gravity measurements taken by NASA's Grace Satellites show a higher readings in the centre of the crater.
+This corresponds to the slightly raised area of the mascon, detected by another imaging method, says von Frese.
+But what was interesting was that the coastline, where Australia would have fitted together with Antarctica, took a 'bite' out of the concentric rings or shock waves, around the crater.
+Von Frese says this suggests that the ocean between Antarctica and Australia opened after the crater was formed.
+He thinks the meteorite that caused the crater could have hit 250 million years ago, triggering a process that culminated in the break up of Gondwana 100 or so million years later.
+Mixed reception
+Von Frese's report has been met with a mixed response from the Australian scientific community.
+"I'm quite excited about the possibility that this is another crater," says Dr Peter Morgan, of the University of Canberra.
+Morgan trained in gravity analysis at Ohio State University and says he has ground-based gravity and radar measurements of the same area.
+He says he will now make it a priority to process the data and share it with the other researchers to see if it supports the theory.
+Earth scientist, Professor John Talent, of Sydney's Macquarie University says before the land structure can be linked to the Permian extinction, a precise age for it is needed. 
+Von Frese's team did not directly date the crater; it's almost 2.5 kilometres beneath the ice.
+Talent also says that research in the past couple of years suggests the Permian extinction was a result of a number of events extending over several million years rather than an instantaneous impact.
+Vulcanologist Peter Whitehead, of James Cook University in Cairns says volcanic activity played a central role in the Permian extinction. 
+He says one suggestion has been that meteorite impacts send shock waves through the Earth and cause volcanic activity on the other side of the planet.
+
+The discovery of 11,000 year old figs shows people became farmers much earlier than we once thought
+Dried-up figs found in Israel may have been the first cultivated crop more than 11,000 years ago, researchers say.
+The discovery, published in the journal Science, pushes back the earliest estimates of when agriculture began by 1000 years.
+And it suggests that, centuries before people figured out how to plant barley and other crops, they knew how to propagate fruit trees for sweet treats, say researchers Professor Ofer Bar-Yosef of Harvard University and Israeli co-authors.
+"[Some] 11,000 years ago, there was a critical switch in the human mind, from exploiting the Earth as it is to actively changing the environment to suit our needs," says Bar-Yosef, a professor of anthropology. 
+"People decided to intervene in nature and supply their own food rather than relying on what was provided by the gods. This shift to a sedentary lifestyle grounded in the growing of wild crops such as barley and wheat marked a dramatic change from 2.5 million years of human history as mobile hunter-gatherers." 
+People were known to have cultivated figs for thousands of years but this finding surprised even experts. 
+"It is generally accepted that the fig tree was domesticated in the Near East some 6500 years ago," says Bar-Yosef's team.
+"Here we report the discovery of nine carbonised fig fruits ... stored in Gilgal I, an early Neolithic village, located in the Lower Jordan Valley, which dates to 11,400 to 11,200 years ago." 
+A special type of fig
+The figs are a variety that produces a large, sweet fruit, as opposed to the wild type, the researchers say. 
+In this variety, known as parthenocarpic figs, the fruit develops without insect pollination and is prevented from falling off the tree, which allows it to become soft, sweet and edible. 
+But because such figs do not produce seeds, they cannot reproduce unless people propagate them, perhaps by planting shoots or branches.
+"Dried figs similar in size and structure imported from Iran are found today in the markets of London," the scientists say. 
+Dried figs
+The carbonised figs were not distorted, which, the researchers say, suggests they may have been dried for human consumption.
+"Once the parthenocarpic mutation occurred, humans must have recognised that the resulting fruits do not produce new trees, and fig tree cultivation became a common practice," Bar-Yosef says. 
+"In this intentional act of planting a specific variant of fig tree, we can see the beginnings of agriculture. This edible fig would not have survived if not for human intervention." 
+At the same site researchers found foods that must have been gathered, such as acorns and wild oats.
+
+The Milky Way has asymmetrical spiral arms, some longer than others
+Our galaxy is a much wilder looking tentacled beast than suspected, say astronomers who have used a new technique to map the Milky Way.
+Radio astronomers used data from a painstaking galaxy-wide survey of hydrogen gas clouds throughout the Milky Way.
+They found that instead of being a clean, symmetrical spiral, our home galaxy has extra long arms sprouting out on one side and is warped and armless on the other.
+The odd layout could be the result of colossal cannibalistic galactic collisions or intergalactic 'tides', say the researchers online on the journal Science. 
+Astronomer Professor Leo Blitz of the University of California at Berkeley says the most surprising thing about the spiral arms on our half of the Milky Way "is that we could see spiral structure all the way to the edge of the [galactic] disc".
+The long, elegant, spiral arms are visible, despite a galaxy full of dust, because hydrogen gas emits radio waves that penetrate the dust.
+The distances to the various arms could be worked out by the Doppler shift in their radio waves. This is similar, in principle, to how the tone of a train's horn sounds higher-pitched when it's approaching than when it's receding.
+Far side of the Milky Way
+In contrast to the near side of the Milky Way, the far side appears less orderly. Instead of having clearly defined curved arms there's a messy bulging area, explains co-author Evan Levine.
+"It's bent like a vinyl record in the Sun," Levine says. "That would show up in a map like this." As for what causes the weird warping, it could be the result of galactic collisions.
+"This lack of symmetry often occurs as galaxies eat little galaxies," Blitz says.
+Another possibility is that the bulge is caused by the gravitational tug of the Milky Way's small satellite galaxies.
+Visible from the southern hemisphere
+The most obvious of these satellite galaxies are the Magellanic Clouds, which are visible to the naked eye from Earth's southern hemisphere.
+"The Magellanic Clouds are very prominent, like the tides of the Earth," says astrophysicist Professor Frank Shu of the University of California at San Diego.
+Earth's oceans bulge with tides because of the external gravitational tug of the Moon. Likewise, the Magellanic Clouds may cause the bulge in the far side of the Milky Way, he explains.
+More details about the Milky Way's structure are likely to be forthcoming, says Levine.
+Blind spots
+Their new map has a few blind spots caused by the motion of our own solar system inside the Milky Way.
+These blind spots show up on their map as an empty circle at the centre of the galaxy and as two blank wedges on opposite sides of our solar system.
+It's possible that more advanced analyses of the data will glean meaningful information from the hydrogen emissions of those areas as well, says Levine.
+For his part, Blitz is pleased to be able to see so much of the galaxy after many years of trying. He recalls that in 1982 he published another paper in Science describing only a part of a single spiral arm.
+"It's like trying to figure out the shape of a forest when you're sitting in the middle of it," says Blitz.
+
+The number 666 is associated with Satan and may people believe it is a bad omen
+Today is the sixth day of the sixth month of the year 2006. Boil it down and you've got 666, the number of the beast according to the Bible's book of Revelation, which prophecies the end of the world.
+But if the date is enough to send you scurrying under your bedcovers, you may be a victim of what an Australian expert describes as a cognitive virus.
+Professor John Bigelow, an expert in superstition and pseudoscience from Melbourne's Monash University, says the number traditionally has a dark significance for occultists, alchemists, heretics and people of a superstitious bent.
+"They're a bit like a cognitive virus," he says of superstitions.
+"Like computer viruses, they get into people's brains, they cause people to pass them onto someone else ... and the person who hears them finds it difficult to get them out of their mind.
+"But I think it's better not to suppress them. [Superstitions] are like the flu, they need to be managed."
+The mythology of 666 goes back to chapter 13 in Revelation, the apocalyptic final book of the New Testament, which states "Let him that hath understanding count the number of the beast ... his number is six hundred threescore and six".
+Bigelow says much of the imagery in Revelation has a schizophrenic quality and is often invoked by people with schizophrenia.
+But he says it's impossible to say whether the author, John of Patmos, or St John the Apostle, suffered from schizophrenia or delusional thinking.
+Macquarie University's Professor Max Coltheart, an Australian cognitive neuropsychologist, says being superstitious about 666 doesn't necessarily add up to a delusion.
+"If you believe something that people around you don't believe in, and there's no evidence for it, that's a good working definition of delusion," he says.
+"If it's in the Bible someone might call that evidence."
+Associate professor of anthropology Phillips Stevens of the University at Buffalo in New York, says fears of 666 are actually based on a misinterpretation of the Bible.
+He says the beast referred to in chapter 13 isn't Satan but several entities.
+"Biblical scholars have pointed out there are several beasts in chapter 13 and elsewhere, and they all refer variously to Rome, Roman emperors  and Roman cults of God and emperor worship," he says.
+"John of Patmos ... was writing to other persecuted Christians in code."
+Perfect numbers
+Six also has significance because it is the first perfect number, says Bigelow.
+Perfect numbers, which are rare, are the sum of their factors, for example, 6 = 1 + 2 + 3 and it can be divided by one, two and three.
+The next perfect numbers are 28 (1 + 2 + 4 + 7 + 14), 496 and 8128.
+The 666 combination also occurred in 1666, the year of the Great Fire of London.
+However, this also marked the year in which Sir Isaac Newton published his Law of Gravity, leading it to be dubbed the Annus mirabilis.
+Conjuring up thoughts of doom, Satan and rampaging evil in relation to a number is an example of magical thinking, Stevens says, where things associated with good things bring food fortune and things associated with disastrous events bring negative consequences.
+But Bigelow says magical thought can have benefits that science doesn't.
+"Science is not tapping into our emotional nature whereas superstitions are a reflection of something about us," he says.
+"It may be a mistake to think you can control the world by projecting your own associations onto it, to turn it into science, but it's not a mistake to register that we do have these deep correspondences among our ideas."
+
+Keeping cut fruit chilled is the key to keeping vitamin C levels high, food scientists show
+Health conscious but time poor? Grab a pack of packaged ready-to-eat fruit and your body will be none the wiser.
+That's the message from new international research showing that chilled, ready-to-eat, fresh-cut fruit retains high levels of vitamin C and other antioxidants.
+Cutting and packaging fruit has almost no effect on the main antioxidants, scientists report in the Journal of Agricultural and Food Chemistry.
+In fact, levels of some antioxidants increased in selected fruits.
+Researchers including those from the University of California, Davis, took pineapples, watermelon, rockmelon, strawberries, mangoes and kiwifruits and processed half as fresh-cut and left half whole.
+Both lots of fruit were refrigerated under identical conditions for nine days before being tested for nutrient content. 
+Tests revealed only small losses of antioxidant compounds in the cut fruit compared to fruit left whole.
+For example, losses in vitamin C after six days at 5&deg;C were less than 5% in mango, strawberry and watermelon pieces, 10% in pineapple pieces, 12% in kiwifruit and 25% in rockmelon cubes.
+No losses in carotenoids, free radical scavengers that are thought to enhance the immune system, were found in kiwifruit slices and watermelon. Losses in other fruits ranged from 10-15% in rockmelon, mango and strawberry to 25% in pineapple.
+Interestingly, total carotenoid content increased in mango and watermelon cubes in response to light exposure.
+The findings don't surprise Australian food technologist Keith Richardson, who says cold is generally the key to keeping nutritional content.
+"The fruits and vegetables are chilled prior to cutting and they don't gain a lot of temperature during the processing operation. Then they're promptly returned to below 5% before being sent out [in refrigerated trucks to sit in refrigerated supermarket cabinets]," he says.
+Richardson, a food technology liaison officer with Food Science Australia, says provided the cold chain is kept "you wouldn't expect a significant loss of nutrients".
+"Generally speaking, the colder you keep fruit the slower its metabolism, including any breakdown of nutrients."
+Meanwhile, the research team says further studies are now needed to evaluate the effect of treatments on the nutrient retention of fresh-cut fruits.
+This include treatments like modified atmosphere packaging and chemical dips for delaying softening and browning.
+
+Researchers say that rock formations in the Pilbara represent a diverse fossil ecosystem, but not everyone agrees
+Researchers say they have found "compelling" new evidence of the earliest known forms of life on Earth in ancient rock in Australia.
+Australian and Canadian scientists say they have found new varieties of stromatolites, rock formations left 3.43 billion years ago in the Pilbara region of Western Australia.
+If the researchers are right, and the stromatolites represent the fossilised remains of early microbes, this could cause scientists to revise estimates of when life began on Earth; some estimates are as recent as 1.9 billion years ago. 
+The paper, published today in the journal Nature, also fuels an ongoing controversy about whether the formations were made by living things or chemical processes.
+Lead author, PhD student Abigail Allwood from Sydney's Macquarie University, says the scientists found a stromatolite reef formed by microbial organisms.
+The reef, along a 10 kilometre part of the Pilbara known as Strelley Pool Chert (STC), contains new types of stromatolites, some looking like upside down icecream cones, others like egg cartons. 
+"The astonishing thing is [the reef's] age, which is a time in Earth's history when the very existence of life is uncertain," she says.
+"We're seeing evidence not just of life's existence but that it was probably well established and already biodiverse, which suggests it could have emerged much earlier in Earth's history."
+But detractors say they're not convinced.
+Martin Brasier, professor of palaeobiology at the University of Oxford, has long argued against the biogenesis theory of the STC stromatolites. And he isn't convinced by today's paper.
+"Much caution is needed when making claims about the earliest signs of life," he says.
+"In rocks of this great age we must assume the hypothesis of a non-biological origin."
+Seven new types
+The STC stromatolites were first discovered more than 20 years ago when they were declared to most likely be of biological origin.
+Subsequent papers argued various alternative theories, including that they were formed by hydrothermal deposits that produced a mineral crust with structures mimicking stromatolites.
+Today Allwood reports she has found seven different types of stromatolite, potentially reflecting at least seven different types of organism.
+"Stromatolites in the modern environment [are] associated with a whole community of organisms, so potentially we're talking about much more diversity than just seven types of organisms," she says.
+But Brasier argues that Allwood and her team have demonstrated the "exact opposite" of biogenesis.
+He says if the structures had been made by living things they would have produced uniform, rather than varied, shapes.
+The wide range of stromatolites reported in Nature indicates they are actually "self-organising structures of largely physico-chemical origin", he says, like sand dunes or crystal formations.
+Similar structures have been produced in the laboratory without microbes, he says.
+A window on the evolution of life
+Allwood says her research sheds new light not only on when, but how, life began.
+She says the first stromatolites appeared as soon as the "carbonate platform" containing formations became submerged by rising sea levels.
+"It's like the organisms were literally waiting in the wings for the right conditions to emerge and they just pounced and spread rapidly everywhere," she says.
+She says her results also contradict theories that early life emerged and flourished in extreme conditions.
+"What we've found is that the hydrothermal activity occurs immediately stratigraphically below and above the STC," she says.
+"The rise of the stromatolites occurs as the hydrothermal activity goes away and the fall of the stromatolites occurs when the hydrothermal activity comes back.
+"This certainly supports the notion  ...  of life getting a firm foothold and flourishing [in association] with something quite normal."
+She says apart from the determination of the antiquity of life on Earth being "an end in itself", her research will help the search for signs of life on other planets, including Mars.
+"These sorts of studies are crucial for informing techniques and approaches for detecting biosignatures on Mars and how we'll distinguish them when we get there," she says.
+
+Planemos, short for planetary mass objects, are a cross between a star and a planet. Astronomers compare them with a brown dwarf, seen here surrounded by a swirling mass of planet-forming dust and gas
+Too lightweight to be stars but bigger than most planets, a handful of hot young free-floating objects have the raw materials to make their own mini-planetary systems, astronomers say.
+These so-called planemos have discs of cosmic dust and gas circling them, just like some young stars.
+These kinds of discs contain the ingredients for planets; astronomers believe Earth and the other planets in our solar system were forged from such a disc. 
+But planemos, short for planetary mass objects, are unlike normal planets because they do not orbit stars, says Associate Professor Ray Jayawardhana of the University of Toronto.
+He and other researchers present their findings at a meeting of the American Astronomical Society in Calgary, Canada.
+"These things are not orbiting a star. They're by themselves," Jayawardhana says.
+The researchers detected four newborn planemos, just a few million years old, in a star-forming region about 450 light-years from Earth, a relative stone's throw in cosmic terms.
+A light-year is about 10 trillion kilometres, the distance light travels in a year. 
+All four of these objects had dust discs around them, the astronomers report. 
+Scientists also found a disc-skirted planemo interacting with a brown dwarf, a failed star, even closer to Earth, just 170 light-years away. 
+Such a planet-sized object might have been expected to be pulled into orbit around the brown dwarf, but instead the two revolve around each other, and both have the makings for more satellites. 
+An eternal freeze
+These objects, with several times the mass of the giant planet Jupiter but 100 times less massive than our Sun, are cosmic infants only a few million years old.
+Even Jupiter had a disc when it was young, and its dozens of moons were formed from the dust and gas it contained.
+But Earth's rocky moon was probably born when our world collided with another heavenly body early on, and Mars' moons were asteroids captured by the planet's gravity. 
+Planemos are a relatively new player on the cosmic scene, filling the gap between the least massive stars and the most massive planets, Jayawardhana says. 
+"These are the lowest-mass brown dwarfs or really big giant planets, especially when they're young," he says. 
+When young, planemos are still warmed by the heat of formation and are more like stars, he says. But as they age, these planet-esque objects shrink and cool. 
+Other researchers do not use the term 'planet' to describe any satellites that might be formed around a planemo, referring to these as moons or moonlets. 
+If such bodies do form, they would be inhospitable to Earth-type life. If a satellite formed very close to a young planemo, it might be temporarily warm enough for liquid water to exist.
+But Jayawardhana acknowledges that in the long run, life would have dim prospects.
+"Any kind of planet that forms around them is committed to an eternal freeze," he says.
+
+Australian soccer fans might not be disappointed, according to statistical analysis of the Socceroos' chances in the World Cup
+Australia has roughly the same chance of winning the World Cup as you have tossing three sixes with three dice, says a sports statistician.
+Professor Stephen Clarke, a researcher at Swinburne University says Australia has a 180 to one, or 0.6%, chance of winning the final.
+"This is not bad and nowhere near as small as the chance of being killed in a terrorist attack or winning [the lottery]," he says.
+"It's slightly more than flipping eight heads in a row (1 in 256) or tossing three sixes with three dice (1 in 216)."
+While Australia goes into the World Cup as an underdog, Clarke says, statistically speaking, the nature of soccer gives the weaker side a chance.
+He says, if one team is expected to kick two goals in a match and another is expected  to only kick one, the stronger side still only has a 61% chance of winning, with a 21% chance of a draw. The weaker team has an 18% chance of winning.
+Function of rare events
+"Soccer is very variable," he says.
+"In Australian Rules football, suppose one team kicks on average a goal every 10 minutes and the other team kicks on average a goal every five minutes. The chances the weaker team will kick more goals than the other team is quite small.
+"But in soccer it doesn't work that way because goals are much rarer, it's a function of rare events," he says.
+Australia has a 32% chance of making it through to the second round.
+Predictions on various teams' chances at making various stages of the World Cup are posted on the Swinburne sports statistics website.
+They were formulated by Andrew Patterson, a former honours student turned professional punter and consultant number cruncher.
+At the latest analysis the figures showed perennial favourite Brazil has a 29% chance of winning, followed by England with a 10% chance.
+According to Patterson's analysis, Australia the same chance of winning as the Ivory Coast, and Serbia and Montenegro.
+Trinidad and Tobago is ranked at the bottom of the ladder with a demoralising 0% chance of winning the World Cup.
+Factoring in public opinion
+Patterson worked out the statistics using odds from an international online betting exchange and ran them through a computer model taking into account the structural peculiarities of the World Cup competition and other factors.
+"I've taken a combination of the public's opinion as well as past data and my own statistical expertise to come up with a statistical model that predicts a team's chances," he says.
+His model will update predicted outcomes as the tournament progresses.
+Patterson says his analysis also puts Australia as favourite to win its opener against Japan on 12 June.
+"I put the two sides into the computer and based on how they currently stand ... There's a 55% chance Australia will win and a 45% chance that Japan will win," he says.
+"When we factor a draw in we come up with 38%  Australia, 31% Japan, 31% the draw. It's pretty much a hedged result."
+The World Cup kicks off on 9 June.
+
+Patients who take an active role in managing their own health may still need help in the decision-making process, researchers say
+When faced with a tough medical decision, imagine that you're making it for a friend rather than for yourself, a new study suggests. 
+That may make such choices easier, report scientists in the June issue of the Journal of General Internal Medicine.
+"We think that it's understandably easy to get caught up in the difficulty of the moment - a patient has just been diagnosed with a problem, they're facing a complex treatment decision; it's hard to see the big picture," says Dr Brian Zikmund-Fisher of the University of Michigan.
+"It's actually relatively easy for people to gain a different type of perspective by thinking about what they would do if they were recommending for someone else." 
+Zikmund-Fisher and his team looked at a phenomenon known as omission bias.
+This is when a person faced with a medical decision may choose passive nonintervention rather than an active approach due to fear of causing harm to themselves. 
+The researchers asked 2399 people to imagine themselves as a patient, a doctor treating a patient, a medical director creating patient guidelines, or a parent making a decision for a child. 
+The people in the study were then asked to make medical choices in two different scenarios. 
+In one, there is a deadly flu circulating that will kill 10% of people who aren't vaccinated, although the vaccine itself carries a 5% risk of causing death.
+In the second, participants were asked to decide on whether or not to treat a slow-growing cancer with chemotherapy. 
+Changing hats
+Study participants were more likely to choose the active approach when making a decision as a professional, rather than for themselves.
+Some 73% of those imagining themselves as doctors would opt for the vaccine, compared to 63% of those posing as medical directors and 48% making the decision for themselves.
+A total of 68% of those taking the physician or medical director role opted for chemotherapy, compared to 60% of those in the patient role. 
+Thinking as parents, 57% of study participants would choose the vaccine for their child, and 72% would opt for chemotherapy. 
+This suggests, Zikmund-Fisher says, that if a child is already sick a parent may feel more comfortable choosing active treatment than when making the decision to choose preventive but potentially risky treatment for a healthy child. 
+Advice from doctors?
+Doctors are increasingly allowing patients to be a part of the decision-making process, Zikmund-Fisher notes. But the findings suggest they shouldn't opt out of advising patients entirely.
+"The physician might be able to act as a coach to help guide the decision making process," he says.
+Doctors could propose that patients try to think of themselves as making the decision for a friend, he explains. 
+"Helping the patient to take a step back might make for a better decision-making process all around."
+
+Feeling itchy?
+Genes and gender help determine an individual's urge to scratch an itch, suggests a new study.
+The study on pruritus, otherwise known as itch, is the first to demonstrate sex differences in itch-induced scratching behaviour in animals.
+The researchers studied mice, but they say the findings could apply to humans and other mammals.
+The conclusion? Females scratched themselves 23% more often than males did.
+"We haven't investigated the underlying mechanisms of the sex difference yet, but they usually involve gonadal [reproductive gland] hormones, such as oestrogen, progesterone and testosterone, either during development or in adulthood," says Professor Jeffrey Mogil, one of the researchers.
+Mogil, a specialist in the genetics of pain at McGill University in Canada, and his colleagues induced itching in the mice by administering chloroquine, a malaria drug that causes itchiness.
+The researchers also used histamines, compounds produced by mammalian tissues to dilate small blood vessels. Histamines are largely responsible for the itchiness associated with allergies, hence the relief provided by antihistamines.
+The team's findings are published online in the journal Pain.
+Mogil says itch is one of the most common reasons people seek medical care.
+He explains that pruritus is an important symptom of many skin, systemic and autoimmune diseases. 
+Numerous medications, such as the malaria drug administered to the mice, cause itching as a troubling side effect. Itching can also be a chronic condition in its own right.
+Are you in pain?
+The most common reason people seek medical attention, of course, is pain.
+Interestingly enough, Mogil and his team found that individuals sensitive to pain are more resistant to itch, while those with less pain sensitivity have a greater tendency to scratch.
+"I think pain and itch are wired up in the brain as opposites, in a sense, such that inheriting particular forms of pain/itch-relevant genes would simultaneously make you more sensitive to pain and less sensitive to itch, or vice versa," he speculates.
+The researchers pointed out that scratching to the point of pain is a well-known strategy for alleviating itch. Conversely, pain medications and local anesthesia often intensify histamine-induced itching.
+Women feel the pain
+The pain-itch correlation, however, is complicated by findings from another study last year in the journal Plastic and Reconstructive Surgery, which found that women feel pain more intensely than men do.
+Dr Bradon Wilhelmi, a plastic surgeon who authored the paper, discovered that women have, on average, 34 nerve fibres per square centimetre of facial skin while men only possess around 17 nerve fibres over the same area.
+"Because women have more nerve receptors, they may experience pain more powerfully than men, requiring different surgical techniques, treatments or medicine dosages to help manage their pain and make them feel comfortable," Wilhelmi says.
+It could be that women are more sensitive than men to both pain and itch, or that women have evolved some level of pain tolerance, perhaps due to giving birth.
+Mogil hopes future research will show which genes turn the urge to itch up or down, how the proteins made by those genes work, and how the same genes may be linked to pain sensitivity.
+
+Isisfordia was a small crocodile - only a metre long, weighing around 3 or 4 kilograms
+A new fossil from the Age of the Dinosaurs suggests modern crocodiles first evolved in Gondwana, says an international team of palaeontologists.
+The team reports on the fossilised remains of the most primitive ancestor of modern crocodiles, discovered near an outback Australian town in Queensland, in the Royal Society journal  Proceedings B today.
+"Up until now, the kinds of creatures that seemed to be the ancestors, or close to the ancestors, of all modern crocodiles have come from places like Belgium, from England, from the USA," says team member Dr Paul Willis.
+"So that's where we thought the group originated."
+But he says the new specimen, Isisfordia duncani, shares more features in common with modern crocodiles than any specimens found in the northern hemisphere.
+"It really defines that branch of crocodile evolution more clearly than anything else we've come across to date," says Willis, an honorary research associate at Sydney's University of New South Wales.
+The researchers say that, at 98 to 95 million years old, Isisfordia predates modern crocodiles by about 20 million years.
+"Ours is the grand-daddy of crocodiles," says Willis.
+Ball and socket joints 
+Modern crocodiles are defined by having ball and socket joints between their vertebrae. And Willis says this gives them a very flexible yet strong backbone.
+"Crocodiles have incredible bursts of very violent energy and so you need a strong backbone to be able to withstand that," he says.
+Modern crocodiles also have a hard palate that reaches right to the back of the mouth, which means they can breathe at the same time as eating something under water, says Willis.
+The palate also strengthens the snout, bracing it and distributing forces when the crocodile bites something.
+"Crocodile bites are second only to Tyrannosaurus as the most powerful known bites of all time," says Willis.
+Willis says all these features would have given Isisfordia and its descendants greater evolutionary advantage than its predecessors in aquatic environments.
+Complete skeleton
+Willis and colleagues analysed two fossilised skeletons first discovered in the mid-1990s in a creek bed in Isisford, in central-western Queensland, by former deputy mayor of the town, Ian Duncan.
+One specimen is almost a complete skeleton with just the snout and face of the crocodile missing. The other is a complete skull.
+"Between the two we have a complete skeleton," says Willis. "We know what the whole animal looked like and it's very rare to get that."
+The researchers know the two are from the same species because they have the back of the skull of both.
+A small croc
+Isisfordia was a small crocodile, only a metre long, weighing around 3 or 4 kilograms, says Willis.
+He says it was the only known crocodile in Australia at that time and wouldn't have had much competition.
+Willis says it would have lived in a swampy river delta that opened into a large inland sea and survived on eating, among other things, fish and other small vertebrates, insects and crustaceans.
+Isisfordia would have been the most immediate ancestor of all modern crocodilians, says Willis.
+This includes crocodiles, alligators and creatures such as gharials (long thin-snouted crocodiles that live in the Ganges River) and caimans (close relatives of alligators from South America).
+Gondwana overlooked
+Willis says this is not the first time that Gondwana has been overlooked as a site of evolution.
+"The fossil record is loaded to the northern hemisphere because there are more sites and more people looking for fossils," he says.
+"But as we're finding more fossils in the Gondwanan continents it appears that a lot of groups that we previously thought originated in the northern hemisphere - or in Laurasia - actually have older representatives here in the southern continents, and in this case in Australia."
+Willis is a reporter on ABC TV's Catalyst program.
+
+Female black swans slip away from their protective partners for illicit encounters, new research shows
+Swans have long been viewed as a symbol of fidelity and everlasting love. But they are in fact cheating philanderers that regularly flee the nest for extramarital sex, Australian researchers reveal.
+DNA testing has shown that one in six cygnets is the product of an illicit encounter, smashing the birds' monogamous image. 
+Now researchers at the University of Melbourne's zoology department are trying to establish how the females manage to slip away from their partners, who are renowned for being protective, to mate on the side. 
+"Swans have long been renowned as symbols of lifelong fidelity and devotion, but our recent work has shown that infidelity is rife among black swans," says Dr Raoul Mulder, whose team is busy fitting tracking devices to scores of swans. 
+Mulder says DNA paternity testing points to extramarital activity among swans but it remains unclear how the illicit encounters take place. 
+In an effort to learn more, up to 60 male swans at Melbourne's Albert Park Lake are being fitted with a tiny microchip attached to their tail feathers. 
+The females, in turn, are being fitted with a miniature tracking device, known as a decoder. 
+"When a male and female copulate, the female's decoder unit detects the microchip implanted in the male's tail feathers, registering the male's identity, as well as the time of copulation," Mulder says. 
+"All mating events are logged onto the decoder unit, so that a complete record of her mating behaviour over several weeks can be downloaded when the swan is recaptured." 
+Mulder says the study targets black swans because they are large enough to wear the tracking device and are more common than their introduced white cousins. 
+As well as providing a snapshot of the sexual activity of swans, the research could reveal extremely sophisticated mating choices by the female birds, Mulder says. 
+"There are risks associated with mating with other birds so there must be some evolutionary benefits," he says.
+The study could point to ways in which females try to ensure the fitness of their offspring by seeking out the superior genes of another mating partner, he adds. 
+The three-year, A$200,000 (US$149,000) study is funded by a grant from the Australian Research Council.
+
+The Crab Nebula with a central pulsar surrounded by rings of high-energy particles
+An astrophysicist who helped first identify pulsars and mentored many of Australia's radio astronomers has been honoured in the Queen's Birthday Honours List.
+Professor Phillip (Pip) Hamilton, deputy vice-chancellor (research) at Deakin University, will today be honoured for his contribution to radioastronomy and tertiary education.
+Pulsars are collapsed stars that can emit regular pulses of radio waves several times a second and were discovered just as Hamilton was completing his PhD in 1969.
+He says at the time, pulsars were dubbed 'LGM 1'.
+"LGM stands for 'little green men' because [the pulsing signal] looked like something that was very, very regular," he says. 
+"It had to be artificial, didn't it, because no one had ever seen these things before."
+But after four or five pulsars had been found, Hamilton says the 'little green men' theory didn't hold up anymore. And today there are about five or six hundred known pulsars.
+Hamilton spent 20 years studying pulsars and recalls one occasion where he was involved with a team using the Parkes telescope to take a second look at a suspicious sighting made by another telescope.
+"We actually discovered this pulsar, a very interesting object, in the middle of a thunderstorm," he says.
+"That's very exciting stuff."
+Hamilton describes himself as "half engineer" and has had major involvement in designing several telescope control systems including that at Parkes and the radio telescopes of the University of Tasmania.
+"I'm a hands-on person. If something breaks down in the office I'm there before anybody else with a screwdriver in the hand," he says.
+
+Debris disc around Beta Pictoris showing light reflected by dust around the young star
+Astronomers have discovered a solar system that seems like an early version of our own, the US space agency says.
+It has huge quantities of carbon gas mixed with a cloud of dust surrounding a young, yellow star called Beta Pictoris.
+The star and its emerging solar system, in which planets could already be forming, is less than 20 million years old, say the researchers.
+The abundance of carbon gas in the dust disc surrounding the star means that the planets being formed could be rich in graphite and methane much like those of our solar system in the early stages, they say. 
+The astronomers, led by Dr Aki Roberge, of NASA's Goddard Flight Center, is published in the journal Nature.
+"There is much, much more carbon gas than anyone expected," Roberge says.
+"Could this be what our own solar system looked like when it was young? Are we seeing the formation of new types of worlds? Either prospect is fascinating." 
+The astronomers made their observations using the Far Ultraviolet Spectroscopic Explorer satellite launched in 1999. 
+Beta Pictoris
+First discovered in 1984, Beta Pictoris is located in our galaxy, is 60 light-years from Earth and has been measured at 1.8 times the Sun's mass. 
+Images of Beta Pictoris taken by the orbiting Hubble Space Telescope show it could have a Jupiter-type planet already and possibly also rocky planets in the course of formation, astronomers say.
+
+Restricting an infant's diet without a clinical diagnosis of food allergy could place him or her at risk, researchers say
+Parents are more likely to think their infant is allergic to certain foods than is actually the case, according to a new UK study. 
+Dr Taraneh Dean of the University of Portsmouth and her colleagues found that more than half (54%) of a group of one-year-olds were avoiding some foods because their parents perceived them to have had reactions to items such as cow's milk, wheat, eggs or additives. 
+But overall only 2-6% of the infants had clinically confirmed food hypersensitivity, the researchers report in the Journal of Allergy and Clinical Immunology. 
+Dean and her team surveyed a group of 969 parents when their infants were three, six, nine and 12 months of age.
+At one year, the infants underwent skin prick testing to investigate their sensitivity to a number of allergens. 
+During the course of the study, infants whose parents reported symptoms of food hypersensitivity had a test known as an open food challenge. 
+If these challenges suggested food hypersensitivity, the children then underwent double-blind, placebo-controlled food challenges, which are considered the 'gold standard' in diagnosing food hypersensitivity. 
+At three months of age, according to parental reports, 14% of infants had adverse reactions to food, while 7% did by one year of age. 
+Among all the children, almost 26% had been reported at some point by their parents to have food hypersensitivity. 
+But open food challenges identified food hypersensitivity in just 14%, and double-blind, placebo controlled testing confirmed it in 6%. 
+Skin prick testing found just 2% of the children had sensitivity to milk, egg, fish, peanut, sesame or wheat. 
+"[The findings] emphasise the need for accurate diagnosis to prevent infants being on unnecessarily restricted diets, which may be associated with inadequate nutrition in this important period of growth and development," the researchers conclude.
+
+A new sensor made of nanomaterials could give robots a sense of touch like we have with our fingers
+A new type of sensor may one day give robots the power to "feel" surfaces and perform delicate operations in the same way that human hands do today, say US researchers.
+Vivek Maheshwari and Professor Ravi Saraf, of the Department of Chemical Engineering at the University of Nebraska in Lincoln, report on the new device in today's issue of the journal Science.
+They say their sensor could give a robot tactile sensitivity comparable to that of human fingers.
+Robots equipped with such sensors could be used in minimally invasive surgery, where tiny incisions and tiny tools are used to target very specific areas in the body.
+The new sensor is an electroluminescent film that glows in response to pressure and texture.
+When an object is pressed into the film, the light from the film is captured by a specialised camera and translated into a picture. 
+Sensor feels out a coin
+To illustrate the power of their new sensor, Maheshwari and Saraf pressed coins against the device. 
+A US penny produced an image detailed enough to show the wrinkles in the clothing of Abraham Lincoln, who is pictured on the coin, and the letters "TY" in "LIBERTY".
+A robot's "hands" could be coated with the sensor film and the signals received could be used to guide the robot in performing surgery, say the researchers, in the same way that surgeons now use their sense of touch to find tumors or gallstones. 
+"Moreover, there is great interest in developing humanoid robots that can sense shapes, textures, and hardness and manipulate complex objects, which are not readily possible by vision alone," say Maheshwari and Saraf.
+Their new film is made of alternating layers of gold and semiconducting cadmium-sulfur nanoparticles separated by nonconducting, or dielectric, films. 
+Nanoparticles are extremely tiny, a nanometer, or a billionth of a metre, or less in diameter. 
+Dr Richard Crowder of the School of Electronics and Computer Science at the University of Southampton in the UK says the development of tactile sensors is one of the key technical challenges in advanced robotics and minimally invasive surgery.
+"The unique sensor developed by Maheshwari and Saraf could prove to be a key advance in technology, for reasons including relatively simple construction, apparent robustness, and high resolution," he says in an accompanying editorial in Science.
+
+Researchers say they've cured bubble boy disease in dogs and this has implications for humans with the genetic abnormality(Image: iStockphoto)
+A new treatment has cured basset hounds with bubble boy disease, a life-threatening genetic disorder that disables the immune system, according to a recent study.
+The disease, called X-linked severe combined immunodeficiency (XSCID), affects male dogs and around 1 in 100,000 boys, all of whom inherit a faulty gene from one of their mother's X-chromosomes.
+The dog study suggests the new treatment may become available to people in future.
+At present, there is only one treatment for the disease, which was brought to the public's attention in a popular 1976 film called The Boy in the Plastic Bubble, starring John Travolta.
+He played David Vetter, a young man who spent his entire life in a sterilised environment. The real-life Vetter died in 1984.
+New approaches
+Boys diagnosed with the condition are given bone-marrow transplants that can replenish stem cells responsible for renewing new functional immune cells.
+Gene therapy, in which the individual's own bone marrow cells are cultured in a lab with the normal gene, showed some success in treating 10 of 11 boys during a 1999 French study.
+But three of the test subjects later developed leukaemia related to the process.
+"Although ex-vivo (outside of the body) gene therapy has been shown to be capable of restoring normal immune function in XSCID boys, there are several potential problems with this approach," says Dr Peter J. Felsburg, who led the recent work and is a professor of immunology at the University of Pennsylvania 's School of Veterinary Medicine.
+Felsburg and his colleagues tried a new approach by directly injecting the corrected gene via an engineered virus into the bloodstream of four "bubble boy" basset hounds.
+Three of the four dogs have maintained healthy immune systems over a year after receiving the genes.
+The fourth dog received a lower dosage, which suggests there is a lower limit to the dose before the gene can restore immunity.
+The findings were published recently in the journal Blood.
+Too early to say it's safe
+Jennifer Puck, who is a researcher in the Division of Immunology and Rheumatology at the University of California, San Francisco, is a leading expert on XSCID and related immunodeficiency diseases.
+At the April conference Primary Immunodeficiencies: Past, Present, Future, Puck presented information on a new method she and her colleagues have developed for diagnosing the diseases in young infants.
+Puck says the basset hound treatment "is a great idea, but its application to humans is far in the future. It is still way too early to say that it is safe."
+She explained that the French children who developed leukaemia did not become ill until 30-34 months after the treatment.
+Puck, however, welcomes new methods for curing immunodeficiency diseases, which can affect both boys and girls. XSCID, which only affects boys, is just one of many related conditions.
+"Newborns affected with severe immunodeficiency look completely healthy at first because they have antibodies from their mother," Puck says.
+"Unfortunately, something really serious has to happen before the genetic disease is suspected, but by then, the baby often is not in good shape."
+She hopes universal screening soon will look for the diseases in all babies when they have their blood tests shortly after birth.
+
+Stargazers hope to learn more about Pluto and its moons during the occultation
+Earth and Pluto will move exactly in line with a star in a rare astronomical event known as an occultation.
+Occultations occur when one celestial body moves in front of another, hiding it from view.
+The event, during which a faint star catalogued as UCAC 2603 9859 will be occulted by Pluto, will occur at 02:25 AEST on 13 June (16:25 12 June UTC) and will last less than two minutes.
+Teams of astronomers have travelled from around the world to view the occultation.
+The main visibility areas will be in New Zealand and southern Australia.
+Amateur astronomers with large telescopes will also be attempting to view the occultation, good weather conditions permitting. 
+The shadow cast by Pluto, the smallest and most distant planet in the solar system, as it tracks across the Earth is only 2,300 kilometres wide - the same as its diameter.
+Learning more about Pluto
+The occultation will help explain some of the mysteries of Pluto's nitrogen atmosphere and whether it has a system of rings similar to Saturn, astronomers say.
+It also offers one of only a few opportunities to obtain data to fine-tune experiments on NASA's New Horizons space mission due to reach Pluto in 2015.
+Dr Mark Buie, from Lowell Observatory in the US and a leading authority on occultations, says the occultation could provide new insights into conditions on Pluto.
+"If the planet had no atmosphere, when it moved in front of the star the star would disappear instantly," he says.
+"But an atmosphere refracts the light a little - it gets spread out, so we see the star get gradually fainter as it goes behind Pluto.
+"The signature of that light curve, how it diminishes with time, allows us to measure fundamental properties of the atmosphere - what it's made of, its temperature and how extensive it is."
+New Zealand observations of a Pluto occultation in 1988 first confirmed that Pluto had an atmosphere and new data will give scientists an idea about what happens to Pluto's atmosphere as it gets further from the sun. 
+"We've only seen Pluto through a quarter of one orbit," says Buie, "and some models predict that the atmosphere will freeze right out. We'd like to test that." 
+The event is even more significant because of the recent discovery of two new satellites to add to Pluto's moon Charon. 
+"That would be fantastically exciting because it would give us a shot at constraining their size," Buie says.
+Detailed information about the occultation can be found here.
+
+Hormonal changes linked to the seasons may change the shape of your body during the year
+Seasonal changes cause fat to shift locations in our body, altering the shape of our figures at certain times of the year, according to a new study.
+Varying testosterone levels drive the shape changes, the study, which has been accepted for publication in the upcoming issue of  Psychoneuroendocrinology suggests.
+ The hormone, often associated with brawn and aggressiveness, fluctuates over the seasons in both men and women.
+The most evident changes occur around the waist and hip region, the study says. When testosterone levels rise, women became less curvy and fat shifts toward the waist.
+Other research has determined that the opposite happens in men, who retain more fat in the abdominal region when testosterone levels fall.
+The scientists examined seasonal testosterone fluctuations in the saliva of 220 women and 127 men. They also measured the waists and hips of the female study participants over the seasons.
+Women more curvaceous in winter
+"We found that women's and men's testosterone is highest in autumn," says Sari van Anders, a PhD student at Canada's Simon Fraser University who led the research.
+"As well, women's waist-to-hip ratio (how big the waist is relative to the hips) is highest during autumn, and central measures of fat deposition, like abdominal fat, were also somewhat higher in autumn (for women)."
+Women also had high testosterone levels in summer. Men showed lowest testosterone levels in spring.
+Van Anders, a doctoral candidate in behavioural neuroendocrinology, says "This suggests that patterns of fat deposition, but not overall fat, are slightly different depending on the season, with more fat being deposited in the central waist region in autumn (in women)".
+The study suggests women look more curvaceous in winter and spring.
+Men, Van Anders says, look manlier during spring when waist and hip size becomes more uniform and less feminine.
+"While we didn't test this, a large body of previous research has found that men find lower waist-to-hip ratios in women more attractive in Western nations," van Anders says.
+"As well, a large body of research finds that lower waist-to-hip ratios are associated with better fertility parameters and health parameters. This suggests that women should be perceived as slightly less attractive in autumn."
+The researchers don't know whether the changes are apparent on a conscious or subconscious level, since they occur gradually over time and do not dramatically alter appearance.
+It's all about reproduction
+Randy Nelson, a professor of psychology and neuroscience at Ohio State University, and one of the world's leading experts on how the seasons affect humans and animals, says the study "is a novel and important finding".
+"There have been previous demonstrations of seasonal changes in hormones, including testosterone, in humans, as well as seasonal influences on the timing of conception," he says.
+"About 6 years ago, a graduate student of mine even showed seasonal changes in cognitive performance among people!"
+The scientists are not sure why these fluctuations in body shape exist.
+Van Anders says the changes might be byproducts of testosterone changing seasonally for reasons unrelated to waist-to-hip ratio, such as health, immune function, fertility and behaviour.
+
+A vacuum-based robot could climb tall buildings more efficiently than those with suction caps and claws, its designer says
+A wall-climbing robot could replace people in building inspections and one day survey urban war zones, where corners, rooftops and building materials thwart otherwise capable robots.
+The City Climber rover, being developed by Professor Jizhong Xiao and his team at the City College of New York, uses a vacuum chamber to get vertical.
+The robot is part of a project that aims to automate mandatory building inspections.
+"New York City mandates that the facades of buildings be inspected every five years," says Xiao.
+"But the current manual inspection is time-consuming and the cost is very high."
+Xiao thinks his robot can do the job faster, cheaper, and more thoroughly than trained technicians, who typically perform their gravity-defying work from suspended scaffolding.
+Conventional robotic wall climbers typically employ more superhero-like methods: sticky feet, suction cups, claws, or magnets.
+But those grippers are only as good as the surface they make contact with.
+Suction cups or sticky feet, for example, work best on smooth surfaces such as glass or marble, but not so well on brick.
+Clawed toes clamber well over rock and brick but slip on glass.
+What's more, such devices tend to move tentatively and cannot navigate over a variety of textured surfaces.
+Vacuum technology
+Getting a robot to both cling to a wall and maneuver effortlessly over it are among the two biggest challenges that face researchers focused on wall-climbing robots, says Professor Ning Xi, director of the Laboratory of Robotics and Automation at Michigan State University.
+"In both aspects, the City Climber is probably the best in the world right now," says Xi, who is not associated with the project.
+The one kilogram device clings to the wall by way of a vacuum rotor located in the centre of its underbelly.
+The rotor's impeller draws air in from the centre of the device and spews it out toward the edges.
+The column of circulating air creates a region of low air pressure inside the vacuum chamber. Because the surrounding air pressure is higher, it pushes down on the device, keeping it tight to the wall.
+Small wheels on the underbelly of the device drive the robot forward and back.
+By linking two triangular-shaped modules with a hinged arm, the researchers were able to make the City Climber manoeuver around 90 degree angle corners and transition from a wall to a roof, all with the strength to pull or carry a payload four times its weight.
+"They have achieved one of the highest payloads reported in the literature," says
+Professor Nikos Papanikolopoulos of the University of Minnesota.
+Xiao plans to equip his rover with a high-resolution digital camera.
+
+The good news is that beer may prevent prostate cancer. The bad news is that you'll destroy your liver if you drink enough to have any effect
+One of the main ingredients in beer appears to thwart prostate cancer, according to findings released by US researchers.
+But you would have to quaff more than 17 pints to imbibe a medically effective dose of xanthohumol, the apparently cancer-fighting antioxidant found in hops,  says researcher Emily Ho.
+"From my studies, you would have to drink an awful lot of beer," says Ho, assistant professor of health and human science at Oregon State University.
+"So the counter effects of the alcohol may outweigh any health benefits from drinking beer." 
+Co-author Fred Stevens of the university's College of Pharmacy, says it's feasible to make pills containing concentrated doses of xanthohumol or to bump up the level of the chemical in hops.
+Scientists in Germany have already brewed up a beer containing ten times as much xanthohumol as found in traditional recipes, Stevens says.
+The brew is being marketed in Germany as a healthy beer, but any effect on cancer rates is yet to be shown, he says.
+Beer and pizza
+Richard Atkins, head of the US National Prostate Cancer Coalition, says tomato sauce is also believed to be an effective cancer fighter.
+This means that beer and pizza could be a winning anti-cancer formula.
+"It's every man's dream to hear that beer and pizza can prevent cancer," he says.
+"Bur our hope is that men know the facts and get tested for prostate cancer. Food no matter how helpful it may be is not a full preventive for prostate cancer." 
+While the research regarding xanthohumol is promising, Ho cautions that further study is necessary. 
+"The one caveat is that all our work is done in a laboratory system using cultured cells with purified compounds," she says.
+Now for more good news
+Meanwhile, a separate study has found that drinking coffee may help prevent the liver disease alcoholic cirrhosis. 
+The study of more than 125,000 people found that for each cup of coffee they drank per day, participants were 22&nbsp;% less likely to develop alcoholic cirrhosis.
+"These data support the hypothesis that there is an ingredient in coffee that protects against cirrhosis, especially alcoholic cirrhosis," concludes the report from the Kaiser Permanente Medical Care Program in Oakland.
+The authors said they could not determine whether it was caffeine or another ingredient in coffee which had the protective effect.
+The study is published in the American Medical Association's Archives of Internal Medicine.
+The authors say the findings don't suggest heavy drinkers should rely on coffee to prevent alcoholic cirrhosis.
+"Even if coffee is protective, the primary approach to reduction of alcoholic cirrhosis is avoidance or cessation of heavy alcohol drinking," they say.
+
+The findings do not preclude the possibility of increased risk of suicide among small populations of individuals, the researchers say
+Newer antidepressant drugs may not raise the risk of suicide as previously suggested, say researchers, who document a drop in suicide rates in the US since the drugs were introduced.
+Dr Julio Licinio of the University of Miami and colleagues report in the June issue of the journal Public Library of Science Medicine that the new SSRI antidepressants could have saved more than 30,000 lives. 
+"Our findings certainly suggest that the introduction of SSRIs has contributed to reduction of suicide rates in the United States," says Licinio who did the study while at the University of California Los Angeles.
+"However, the findings do not preclude the possibility of increased risk of suicide among small populations of individuals." 
+Millions of people use SSRIs (selective serotonin reuptake inhibitors), including Pfizer's Zoloft, GlaxoSmithKline's Paxil and the first drug of this type, Eli Lilly's Prozac, or fluoxetine.
+Warnings
+The US Food and Drug Administration introduced "black box warnings" on the most popular SSRIs in 2004 after studies in the US and Britain suggested the drugs may raise the risk of suicidality in children and adults.
+"Although the current issue concerning antidepressants and suicidality requires further examination, we believe that many more lives have been saved than lost since the advent of these drugs," say Licinio and team. 
+Suicidality is defined by feelings, thoughts, and behaviours related to suicide, but the researchers say actual deaths caused by suicide are a better measure of whether there is a benefit from antidepressants.
+Licinio's team studied federal data to show the US suicide rate held steady for 15 years prior to the introduction of Prozac in 1988, then dropped steadily over 14 years as sales of the antidepressant rose. The research team found the strongest effect among women. 
+Mathematical modelling of probable suicide rates from 1988 to 2002, based on pre-1988 data, suggests 33,600 fewer people have committed suicide since Prozac hit the market, Licinio says.
+The actual suicide rates fluctuated between 12.2 and 13.7 suicides per 100,000 people until 1988, and then gradually fell to the lowest 10.4 per 100,000 in 2000, Licinio's team reports. 
+During that time prescriptions of fluoxetine ballooned from about 2.5 million in 1988 to more than 33 million in 2002. 
+Study does not prove benefit
+In a commentary on the new study, Associate Professor Bernhard Baune and Professor Philippa Hay of James Cook University in Australia say the type of study performed by Lucinio and colleagues cannot prove for certain "whether antidepressants do harm or good at a population level." 
+But they say that the study "does not support an association between increased suicide and increased fluoxetine prescription rates."
+Licinio's team acknowledges there may have been other reasons why the suicide rate declined.
+Their research was funded by the National Institutes of Health and the Dana Foundation and did not have any pharmaceutical company funding. 
+The researchers declare no competing interests. Licinio accepted an offer to consult for Eli Lilly after the research was accepted for publication.
+
+Is the whinny a horse makes when it sees someone it likes different from the one it makes when it sees someone it doesn't like?
+A new database of horse talk and behaviour could help take the mystery out of a horse whisperer's job, US researchers hope.
+Physicist David Browning, an adjunct professor at the University of Rhode Island, and Dr Peter Scheifele, a research associate at the University of Connecticut are compiling the database in an attempt to correlate nuances in horse whinnies with their differences stress levels.
+They announced their Equine Vocalization Project last week at an Acoustical Society of America meeting in Providence, Rhode Island.
+The information could help shed light on the communication styles of other equines, such as donkeys and zebras, and even improve how veterinarians, behaviourists, breeders or other animal handlers relate to horses.
+"You would like to find that you get a particular whinny for a particular situation," says Browning.
+Snorts, blows, sighs and whinnies
+Unlike the monotonal vocalisations of cows, goats, and sheep, horses emit a range of sounds from snorts, blows and sighs to whinnies, which also come in the form of nickers and squeals.
+Browning's initial acoustical studies have shown that whinnies have the greatest changes in frequency and could contain information about specific situations.
+When horses are stressed, their vocalisations peak into a high-pitched screams; when they are calm, their whinnies modulate in the middle tones.
+But scientists are still not sure if the changes in frequency can be connected to more specific conditions.
+Browning and Scheifele have begun compiling their database of horse vocalisations from their own recordings and from those of other researchers. The vocalisations are analysed with acoustic software that plots the sound over time.
+They have been categorising the vocalisations by behaviour in order to answer some basic questions. 
+For example, horses have a good memory and can recognise friends, both human and horse. Browning would like to know if the whinny they make when they see someone they like is different from one they make upon seeing someone they don't like.
+Zebras that bark like a dog
+As part of the project, Browning will also be collecting vocalisations of three species of zebra - one that brays like a donkey, one that whinnies like a horse, and one that barks like a dog - to try and get a more complete picture of equine vocalisations.
+Dr Sarah Ralston an associate professor at the Equine Science Center at Rutgers University, isn't sure how much the study will contribute to the practicality of handling horses. 
+But she does think that comparing the vocalisation of horses and zebras could provide some insight into the social organisation of different equines.
+"One [zebra] is like a horse with harems and lives in groups, whereas another is more solitary. Differences in vocalisations might reflect differences in the social organisation," she says.
+
+If all the Earth's gold was on the surface we could be "knee-deep in the stuff", says researcher
+There's enough gold buried deep within the Earth's core to cover the entire land surface of the planet to a depth of half a metre, an Australian researcher says.
+Professor Bernard Wood, a geologist from Macquarie University, in Sydney made his remarkable calculations based on research published in today's issue of the journal Nature.
+Wood and colleagues chart the early history of our Earth's development starting with the birth of the solar system more than 4.5 billion years ago.
+In particular they focus on the formation of Earth's molten metal core.
+"By looking at other stars that are currently at the state our Sun was in then, we can see that they are surrounded by a flattened disc of dust and gas," Wood says. 
+"We know that within about 10,000 years these formed into small bodies that were about 10 kilometres across."
+Radioactive dating has shown that over the next 100,000 to one million years, those small "planetesimals" collided to form Moon-to-Mars sized planetary embryos. 
+Within 10 to 100 million years, larger planets had formed. "In the case of Earth, it was around 30 million years," Wood says.
+Magma ocean
+Early in its history, the Earth was probably covered in a sea of molten rock, hundreds of kilometres deep. 
+During the planet's development, this "magma ocean" reacted with metals in the planetesimals, extracting many of the most important and interesting elements, including gold, and eventually depositing them in the Earth's own iron-rich core. 
+To calculate how much gold was in the Earth's core Wood compared the composition of the Earth's crust with that of meteorites, which can be used to represent planetesimals. 
+He and other researchers have found that the meteorites had similar levels of all elements that would not normally dissolve in iron.
+But they also noted that meteorites had higher levels of elements such as gold, platinum and nickel. 
+"This tells us that the Earth is chemically very similar to those meteorites, but the Earth's crust is depleted in all those elements that like to dissolve in iron," Wood says.
+There's only one place those elements can have gone - the molten core.
+"We can say that more than 99% of the Earth's gold is in the core," Wood says. "It's a nice image to think we could all step outside and be knee-deep in the stuff."
+
+Passenger air travel is growing at the rate of around 5% a year and could account for 15% of man-made CO2 emissions by 2050
+Restrictions on night flights could ease the aviation industry's fast-growing contribution to global warming, say UK scientists.
+Dr Nicola Stuber and fellow meteorologists at the University of Reading report their findings in today's issue of the journal Nature.
+At certain altitudes, aircraft produce contrails - condensation trails caused when the plane's hot exhaust hits the chilly atmosphere. 
+These contrails have a surprisingly big but also complex effect on the climate. 
+Because they are clouds, they trap heat that is emitted by the Earth's surface, creating a "greenhouse effect" that adds to warming. 
+Yet during daytime, these clouds have a cooling effect because they are white and thus reflect some of the Sun's energy back into space. In certain conditions, contrails can exist for several hours. 
+Stuber and team estimate the radiation caused by contrails at a busy flight corridor in southeast England.
+Using high-resolution aircraft flight data and routine weather balloon data, they looked at "persistent" contrails: wakes that remained for an hour or more after the aircraft had flown over.
+Night flights account for only 22% of Britain's annual air traffic but contribute between 60 to 80% of the greenhouse effect from contrails, the scientists found.
+Winter flights warm more
+Stuber and team also found that flights during the winter months could contribute more to global warming.
+"We also found that flights between December and February contribute half of the annual mean climate warming, even though they account for less than a quarter of annual air traffic," says Stuber. 
+Although there are fewer flights during the winter months, the conditions needed to form contrails - the right temperature, amount of moisture in the air and aircraft altitude - are found more often then. 
+A growing problem
+Global emissions of man-made CO2 are between 6.2 billion and 6.9 billion tonnes per year. Added to this are around 1.5 billion tonnes from land use. 
+Commercial aircraft account for only a small contribution compared with power stations, industry and road traffic. 
+However, passenger travel is growing at the rate of around 5% a year, which means that this share will grow fast.
+A 1999 estimate by the UN's Intergovernmental Panel on Climate Change (IPCC) found that the airline industry accounted for 2% of man-made CO2 emissions in 1992. But it would rise to as much as 15% by 2050. 
+Environmentalists are angry, complaining that airlines get a free ride when it comes to environmental taxes. 
+Changing altitude could also help
+In addition to rescheduling night flights for the daytime, planes could diminish their contribution to global warming by changing their altitude. 
+A study published last year in the journal Transportation Research suggests that the regions of "ice-supersaturated" air where contrails form is only about 500 metres thick. 
+The goal would be to fit sensors on aircraft that could inform pilots where this layer lies, thus enabling them to shift altitude accordingly.
+
+ANSTO says the radiation released from its site was well within regulatory limits and will not affect the health of workers or the community
+The operator of Australia's only nuclear reactor has rejected claims that radioactivity released from its site raises safety concerns.
+The opposition Labor party claims the Australian Nuclear Science and Technology Organisation (ANSTO) has withheld details about an accident at the Lucas Heights facility in Sydney last week.
+A pipe inside a "hot cell" used to produce medical isotopes ruptured last Thursday evening disrupting production of radiopharmaceutical technetium-99n, used in the scanning of bones and organs. 
+"Only one worker was in the vicinity of the incident, but after examination he has been found not to have received any radiation dose," ANSTO said in a release at the time.
+"No measurable contamination was found outside the immediate area where the incident occurred, and there are no off-site consequences."
+But shadow minister for science and research, Jenny Macklin, said yesterday she had obtained an internal email from ANSTO that contained information not previously released by the organisation.
+The email said a small amount of radioactive gases (xenon and krypton) had been released through the stack and the worker involved had received a very small amount of contamination.
+The email said the radiation was quickly washed off the worker and a whole body monitor examination confirmed that he received no internal radiation exposure.
+"Trivial" incident
+In a follow-up statement this week ANSTO rejected Macklin's claims that it had not made relevant information about the incident public.
+ANSTO described the incident as "trivial", although said it had nonetheless informed the regulator, the Australian Radiation Protection and Nuclear Safety Agency.
+Small amounts of radioactive gases are routinely released during radiopharmaceutical manufacture, and reported to the public via ANSTO's annual Environmental Reports, ANSTO said.
+It also said that while the doses received by the public as a result of those releases are so low as not to be directly measurable, they can be calculated.
+The total maximum annual estimated dose to a member of the public from those releases is only a very small fraction of the radiation dose received by everyone each year from naturally-occurring sources of radiation, ANSTO said.
+"The releases which occurred last Thursday evening were not outside the normal release pattern, were well within regulatory limits and could not be detected off-site," the statement said.
+Nuclear debate
+Australia holds about 40% of the world's known uranium reserves and is a major exporter of the material.
+There is currently debate in Australia over government investigations into whether to set up a nuclear power and enrichment industry in the country.
+"Accidents like this show that the community is right to be concerned about the safety of nuclear reactors," Macklin said. "This accident is a stark reminder that things can go wrong with nuclear reactors." 
+But ANSTO rejected Macklin's linking of last week's incident with nuclear reactor safety.
+"The incident did not occur in the reactor, and has nothing to do with reactor safety," it said.
+"This is just deliberate scare-mongering by Labor in relation to a medical research reactor that delivers radioisotopes and radiopharmaceuticals to cancer patients across Australia," science minister, Julie Bishop told ABC Radio News.
+The 48-year-old Lucas Heights plant is Australia's only nuclear reactor and produces radioisotopes for use in more than 440,000 nuclear medicine procedures each year.
+
+Reconstruction of the ancient amphibious bird Gansus yumenensis - the most advanced Early Cretaceous bird yet discovered
+Spectacular 100-million-year-old fossils, complete with three-dimensional bones, feathers and foot webbing, suggest living birds evolved from waterfowl, say researchers.
+Dr Peter Dodson, professor of anatomy at the University of Pennsylvania, and team report in today's issue of the journal Science on five partial skeletons found 2,000 km west of Beijing, China.
+Called Gansus yumenensis, the pigeon-sized bird probably resembled a tern or a loon (web-footed fish-eating birds), the researchers say. 
+It would have been an accomplished flyer and diver and could well be one of the ancestors of modern birds.
+"Gansus is very close to a modern bird and helps fill in the big gap between clearly non-modern birds and the explosion of early birds that marked the Cretaceous period, the final era of the Dinosaur Age," says Dodson.
+He says Gansus is the oldest example of the nearly modern birds that branched off the trunk of the family tree that began with the famous proto-bird Archaeopteryx, which provided evidence that birds evolved from dinosaurs. 
+"Every bird living today, from ostriches ... to bald eagles, probably evolved from a Gansus-like ancestor," says team member Dr Matthew Lamanna of Carnegie Natural History Museum in Pittsburgh. 
+Rich fossil bed
+The fossils were found in an exceptionally rich fossil bed in China's Gansu Province, in a poor farming area near Changma, by an expedition led by team member Dr Hai-lu You of the Chinese Academy of Geological Sciences.
+In the Cretaceous period, 100 million years ago, it would have been a lake, surrounded by lush plant life, filled with crocodiles and fish, and with dinosaurs and early mammals prowling on land. 
+
+Humans aren't the only animal that weigh up costs and benefits
+Rats, like humans, carefully weigh the costs and benefits of making certain decisions, a new study has found.
+The study, accepted for publication in the journal Behavioural Brain Research, is the first to demonstrate this behaviour in non-human animals.
+A person buying a new car, for example, must weigh the cost and the effort needed to make payments versus the value of the car. 
+Rats, and likely all rodents, do something similar, only under a lot more pressure.
+"In its natural habitat, rats are facing the problem that little is under their control, so they are facing various levels and forms of uncertainty all the time," says study leader Dr Ruud van den Bos of the Faculty of Veterinary Medicine at Utrecht University in The Netherlands.
+"For instance, the quality and amount of food items at patches varies over time and between different patches, thus benefits are not always the same."
+"The amount of energy spent to obtain these different items varies during the different foraging sessions, as sometimes it's cold, sometimes it's hot, sometimes it rains, sometimes sudden obstacles are present after heavy storms, etc."
+T-shaped maze forces rats to choose
+Van den Bos and team attempted to duplicate such challenges by manipulating barriers in a T-shaped maze that rats explored. 
+The Wistar rats, a rodent developed for research, entered at the bottom of the "T," which connected two arms.
+At the end of each arm was a chamber filled with treats. One side had a low reward  - one sugar pellet - while the other side had three to five sugar pellets.
+Rats that wanted the higher rewards had to climb steep barriers. It would be like placing a person's favourite dessert behind a high wall that would have to be scaled before the individual could nosh. 
+The researchers varied the size of the barrier and the amount of reward on that side to see how the rodents would react.
+At first the rats went for the easy pickings, but when they determined more sweets were available on the other side of the maze, they exerted additional effort, but only after a certain point. 
+When the pain yielded too little gain, they stuck with the tiny treat.
+The researchers also noted that rats seem to behave according to an internal constant standard, a relative ratio for each situation by which choices are measured. 
+This is comparable to how a car purchaser may enter a dealership with a budget in mind. Since this standard varies depending on the situation, it is possibly part inherent and part created by individuals.
+Rats could get depressed too
+Dr John Salamone, professor and head of behavioural neuroscience at the University of Connecticut, developed the T-maze for previous studies. 
+He also recently authored a paper in Current Psychiatry Reviews  that determined problems in the brain associated with effort-related processes, such as how much energy an individual will put out to obtain a reward, could be linked to depression.
+This suggests rats get depressed too. Salamone's own research indicates interference with dopamine, a neurotransmitter chemical in the brain, may make individuals less likely to work for rewards and biased toward low-effort alternatives.
+"Exertion of effort and energy and energy-related decision-making are fundamental for survival, in humans and other animals, and I am very happy that more and more people are getting involved in this sort of research," says Salamone, who added the new work was "an excellent piece of research."
+
+Migraines have been linked to a better sex drive
+Being prone to migraine may improve some individuals' libido, according to new research.
+A team led by Dr Timothy Houle, of Wake Forest University School of Medicine in Winston-Salem, North Carolina, reports its findings in the June issue of the journal Headache. 
+"The goal of this research was to understand migraine better," says Houle. 
+"By better understanding how the brain is altered with this syndrome, we can develop better drugs in the future." 
+"Migraines have other commonly associated symptoms, such as sleep abnormalities and a higher risk of depression. Altered sex drive may be another quirk of being a migraine," he adds.
+Sex can alleviate migraine pain
+Houle and team note that it is commonly believed that sex drive is reduced by headaches, and sexual intercourse can cause specific types of headaches.
+But, they say, other research has suggested that sexual intercourse may alleviate the pain of migraine in some patients. 
+The researchers tested the theory that migraine and sexual desire may both be associated with serotonin. 
+Reduced libido often accompanies depression treatment with a selective serotonin reuptake inhibitor (SSRI), which increases brain levels of serotonin, whereas migraine is associated with reduced serotonin levels.
+To investigate this complex relationship, Houle and team recruited 59 adults who had at least 10 headaches annually. 
+Twenty-three subjects (7 men and 16 women) were classified as having migraine, and 36 (18 men and 18 women) as having tension-type headache. 
+The subjects completed the self-administered Sexual Desire Inventory (SDI), which allowed them to rate how much they think about sex and how much they desire sex. 
+"Men reported about 24% higher sex drive than did women," says Houle. "And the difference between migraine and tension-type headache was almost equivalent - 20%." 
+Thus, women with migraines reported about the same relative levels of sex drive as men with tension type headaches. 
+On the nine-point scale the subjects specifically rated their own sexual desire compared with that of others of the same age and sex.
+The migraine patients reported the highest level (5.0), which is "above the expected median (4.0) on this item," Houle and team say. 
+Those with tension-type headaches gave themselves an average rating of 3.7 for this item. 
+Sexual desire still normal
+Houle says the migraine patients were aware that they rated their sexual desire higher than that of other patients in the group. 
+But, he adds, "there was no evidence that their sexual desire was beyond that of high normal or that they are hypersexual." 
+"It can now be hypothesised that a serotonergic link may be implicated in both migraine headaches and sexual desire," the researchers conclude. 
+Serotonin receptors also appear to be involved in several aspects of sexual functioning. 
+On the other hand, they point out that there are multiple classes and subtypes of serotonin receptors. Therefore, they conclude that "any neurochemical mechanism(s) that might link serotonin and migraine would likely be sophisticated and multifactorial."
+
+The global IWC meeting has seen a pitched battle for control of the agenda between pro-whaling nations and those who want whaling banned
+Pro-whaling nations have struck an historic blow against the moratorium on commercial hunting, winning their first vote in favour of whaling for two decades.
+The breakthrough came over the weekend at the 70-member International Whaling Commission's annual meeting in the Caribbean island state of St Kitts and Nevis. 
+The Japan-led pro-whaling block is triumphant after forcing a resolution which brands the current ban "no longer necessary".
+The non-binding resolution, which has a one vote margin, doesn't mean the 20 year-old moratorium will be overturned.
+But it signals that the pro-whaling lobby might finally have the muscle to challenge the moratorium.
+This is historic," says said Rune Frovik, secretary of Norwegian pro-whaling lobby the High North Alliance.
+"For the first time in more than two decades the Whaling Commission expresses support for commercial whaling."
+Environmentalists, meanwhile, have labelled the latest vote "tragic" and say it's their worst-ever defeat in the decades-long anti-whaling campaign.
+"This is the most serious defeat the conservation cause has ever suffered at the IWC," New Zealand's environment minister Chris Clark says. 
+The win is also a huge symbolic step forward for Japan, as it strives to lead pro-whaling nations to a majority on the IWC. 
+Federal environment minister Ian Campbell has criticised Japan's attempt to control the IWC.
+"The attempt by Japan to turn the whaling commission back into a whaling club shows just how out of touch they are with world opinion," he says.
+Long awaited success or major setback?
+Japan and its allies on the commission are triumphant, savouring the first-ever fruit of Tokyo's long diplomatic campaign to lift the ban on commercial whaling.
+"This is an historic victory," says Glenn Inwood, spokesperson for the Japanese delegation. 
+"This is the first serious setback the global moratorium has ever had. It is only a matter of time before it is gone completely." 
+Environmental campaigners meanwhile are reeling from the blow, and some were close to tears after the vote.
+"This is the most significant setback since (the moratorium) came into force," says Kitty Block, a lawyer with Humane Society International.
+Focus on management, not conservation 
+The weekend resolution, proposed by commission hosts St Kitts and Nevis, passed by 33 to 32 votes with one abstention. 
+It declares "The moratorium, which was clearly intended as a temporary measure, is no longer necessary." 
+
+The vote represents a major victory for pro-whaling nations led by Japan, who want to turn the IWC away from pure conservation and focus on a return to managing whale stocks for hunting. 
+The moratorium, enforced since 1986, still stands because it needs a 75&nbsp;% majority to be overturned.
+Japan abides by the moratorium, but conducts "research" whaling through what opponents say is a loophole in the IWC charter, as does Iceland.
+Norway ignores the moratorium all together. 
+Around 2,000 whales are taken by the three nations each year and more than    25,000 whales have been hunted and killed since the moratorium. 
+Japan hopes to use the resolution, known as the St Kitts and Nevis declaration, as a political weapon to argue that more states than not on the 70-nation IWC body believe the commercial whaling ban should be lifted.
+Japan complains that anti-whaling states have deadlocked the commission, which was set up in 1946 to prevent whales from passing into extinction through over-hunting.
+Having a majority on the IWC will allow Tokyo to control the commission's agenda for the first time since a moratorium was introduced and, environmentalists fear, let Tokyo frustrate conservation efforts.
+Not all good news for whaling nations
+Sue Lieberman, director of the global species program at WWF International, says the vote should be a wake-up call.
+"What is more important than that is this does show that Japan's recruitment drive has finally succeeded," she says.
+But Lieberman says Japan was defeated in three far more substantial votes that preceded approval of the St Kitts and Nevis declaration.
+In one, Japan sought to remove the issue of hunting dolphins and porpoises from the agenda of the meeting but failed by a 32-30 vote.
+In another, Japan lost its bid to introduce secret ballots, something the group has never done for major initiatives in its 60-year history, officials say.
+And in a third, anti-whaling nations voted down Tokyo's request for coastal whalers to resume a small for-profit inshore Minke whale hunt. 
+"No they did not win when it really counted. And no, this isn't going to change anything," Lieberman says of the declaration.
+"This is purely inflammatory and will not help resolve what we agree is a serious impasse (in the IWC)."
+
+An artificial nose may one day help doctors sniff out disease
+Doctors in the future may sniff patients with an electronic "nose" to detect telltale odours released as a result of disease and illness.
+The technology replicates human and animal olfactory systems, according to a recent announcement by the European Union Information Society's Technologies Program.
+The mechanical sniffer, currently undergoing development and testing, could dramatically change how doctors diagnose illness.
+The technology behind the device was inspired by the human nose, but its effectiveness is comparable to more sensitive animal noses.
+"The human nose is not especially well suited for odour recognition, as compared to the noses of dogs or rats," says Professor &Oacute;scar Ruiz, who is working on the project.
+Ruiz, from the Department of Electronics at the University of Barcelona, Spain, says "There are some groups in the world that have trained dogs to diagnose some diseases like melanoma or prostate cancer in urine."
+He says the sniffing device would do something similar, only it would use bioelectric sensors.
+Sniffing out skin cancer
+The gadget consists of a layer of proteins, designed to mimic natural olfactory receptors, placed on a gold microelectrode mounted on a two-millimetre-long computer chip.
+One end of the chip is immersed in a liquid cell containing additional microelectrodes, all of which connect to an instrument that measures electrochemical changes.
+At present, the researchers are pumping odour-causing chemicals into the liquid cell to record the signature spectrums that result when the nose receptors encounter them.
+Skin cancer cells, for example, create distinctive electrochemical patterns, as do bacterial infections, failing organs and other tissue cells, even when they are healthy.
+So far, the researchers have worked with an olfactory receptor protein from rats and one from humans.
+The proposed electronic nose will need several hundred of such proteins to detect multiple smells.
+The human nose, for example, uses 1,000 different proteins that enable the brain to perceive approximately 10,000 different smells.
+In humans, however, the brain cannot seem to keep up with the nose.
+"The brain gets trained to recognise different odours but, of course, many of them are never recognised," Ruiz says.
+The evolution of smell
+Our hominid and ape ancestors actually had more keen noses, since they relied more upon their sense of smell for mating, socialising, detecting predators, finding food and other tasks.
+Scientists at the Weizmann Institute in Rehovot, Israel, have found that many genes for smell in humans were turned off permanently over the course of our evolution, although the DNA continues to exist as inactive "pseudogenes".
+Ruiz and his team suggest that the electronic nose will return some of these smelling skills to us.
+The invention may even improve upon nature, at least in terms of precision and reliability.
+"We think that a commercial prototype could be available in between five and 10 years, although there are still some important issues to be solved," he says.
+"Initially we expect that the devices will work with body fluids like urine or blood."
+
+A silent, unmanned drone could help crack down on urban crime, US police say
+Police in the US have launched what they say is the future of law enforcement in the form of a drone aircraft, bringing technology usually associated with combat zones to urban policing. 
+The unmanned aerial vehicle, which looks like a child's remote control toy and weighs about 2.3 kilograms, is being tested by the Los Angeles County Sheriff's Department.
+Police say the SkySeer drone will be able to accomplish tasks too dangerous for officers and free up helicopters for other missions.
+The technology could be used to find missing children, search for lost hikers, or survey a fire zone, says Commander Sid Heal, head of the Technology Exploration Project of the Los Angeles County Sheriff's Department. 
+It will also be helpful in tracking down suspected burglars on rooftops and chasing down suspects fleeing on foot. 
+The drone is equipped with low-light and infrared capabilities and can fly at speeds up to 48 kilometres per hour for 70 minutes. 
+High-tech kite fits in a backpack
+The plane collapses and can fit into a shoulder pack smaller than a golf bag. 
+"It's basically a high-tech kite that field officers could set up in a matter of minutes," Heal says. 
+A small camera capable of tilt and pan operations is fixed to the underside of the drone and sends the video directly to a laptop command station.
+Once launched, the craft is set to fly autonomously with global positioning system (GPS) coordinates and a fixed flight pattern. 
+As technology improves, the drone will be outfitted with zoom capabilities. For now, the craft simply flies lower to hone in on its target.
+Police say the SkySeer's stealth quality is a big advantage.
+"The plane is virtually silent and invisible," says Heal. "It will give us a vertical perspective that we have never had." 
+He predicts that unmanned surveillance crafts will become the norm in urban policing. 
+Sam De La Torre, designer of the drone at Octatron Industries, has been working on the project for two years and says he has seen demand from other police forces. 
+Is Big Brother watching you?
+The SkySeer isn't capable of spying into windows yet, but privacy advocates say a future of surveillance by invisible eyes in the sky is an unsettling development. 
+ "A helicopter can be seen and heard, and one can make behaviour choices based on that," said Beth Givens of the Privacy Rights Clearinghouse. 
+"Do we really want to live in a society where our backyard barbeques will be open to police scrutiny?" 
+For now, the sheriffs will continue trial runs of the SkySeer to get a handle on its capabilities and work at fixing glitches in its operation, including a "communication interference" that caused the high tech kite to nosedive and crash during a field test last week.
+
+Relationships, family and social standing are all sources of stress for female baboons - sound familiar?
+Female baboons get stressed about males and even suffer from premenstrual tension, a new study shows.
+According to the research, the number one cause of stress for female chacma baboons (Papio hamadryas ursinus) is when a new male enters a group and may threaten to bully and kill other baboons, especially infants.
+"That suggests to me that females are highly aware of the risks presented by violent young males entering the troop," says Dr Anne Engh, lead author of the study, which was published recently in the journal Animal Behavior.
+Engh, a researcher in the Department of Biology at the University of Pennsylvania, and her team studied approximately 70 male and female baboons over a 16-month period in Botswana's Moremi Game Reserve.
+They collected faecal samples from females for stress hormone analysis.
+Prior research has found that glucocorticoids, a class of steroid hormones, rise when apes, humans and other animals feel stress.
+Baboons get PMT too
+Besides male immigration, reproductive state, predation, rank instability and infanticide also triggered female stress.
+The stress hormone rise during reproductive stages is normal, and indicates that female apes, like women, could experience a potentially cranky PMT phase.
+Female baboons usually exist in stable, hierarchical groups, but the researchers observed two instances where low status females tried to pull rank and stress levels rose.
+In one case, an adult female, her adult daughter and a sister all attempted to usurp the power of another unit. After a week of fighting and high stress, the lower-ranked group gave up.
+In the second period of observed instability, an adult female named Cat ran off with a high-ranked male for several days.
+When she returned, a "Cat-fight" ensued with the other females. The fights not only lowered the status of Cat, but also placed the unfortunate baboon's daughter, sisters, aunt and their children to the bottom of the hierarchy.
+"Our best guess is that poor Cat just had very bad timing," Engh says.
+"When she left the troop with the alpha male, more than half of the troop's females were cycling, so there was probably quite a bit of competition between the females to catch the alpha's eye."
+Anxiety levels also rose when males, attempting to assert their power, killed infants. For several days after an infant's murder, its mother would scream and flee whenever the killing male approached.
+What can baboons teach us about stress?
+Engh says friendships with less aggressive males and grooming with females seems to reduce the females' fear and stress.
+Professor Joan Silk, a University of California at Los Angeles anthropologist noted for her work on the evolution of social behaviour in primates, says she has worked at the same reserve where the new study took place, and that this "account seems consistent with what I know of the females there."
+She says, "The results provide independent confirmation of the supposition that sociality has important consequences for females."
+Baboons in their natural habitat appear to cope with stress better than humans do, Engh says.
+"Humans, in contrast, get stressed out about many things, often things that are of little significance in our lives or are completely abstract threats," she says.
+"We would probably be better off aping baboons and worrying only about the important things in our lives."
+
+Coral reefs have changed dramatically since the arrival of humans, particularly in the last few decades
+Coral reefs have suffered more damage since the 1970s than any time in the last 220,000 years, according to a study that warns of the threats of overfishing and coastal development.
+Scientists from Australia have found that coral reefs in the Caribbean island of Barbados were relatively unchanged for about 100,000 years before the arrival of humans, despite rising and falling sea levels. 
+But according to the paper published in Ecology Letters, modern day reefs now look startlingly different and are dominated by algae and seaweed. 
+Associate Professor John Pandolfi, of the Australian Research Council's Centre of Excellence for Coral Reef Studies, says human activity has made reefs far more susceptible to change. 
+"When you compare that typical coral community in the geological past to the coral community that we see today in Barbados it's fundamentally different," says Pandolfi, who led the study. 
+"It's clear that these modern coral reefs have been significantly altered and the only thing that's different is that humans are around. 
+"We see that the impact of overfishing and coastal development has had a huge effect the likes of which we haven't seen for hundreds of thousands of years."
+Overfishing takes its toll
+Pandolfi studied the preserved remains of entire coral reef communities that lived in the Caribbean up to 220,000 years ago.
+He analysed four periods in the reef's history, when geological activity pushed it to the surface and wiped out the coral community.
+Each time, the sea floor was recolonised and the coral reef returned in a very similar structure with the same species.
+"When we look at large scale perturbations in the fossil record, [such as] global climate change and sea level changes, when the reefs come back .... they appear to assemble in similar ways," he says.
+"So through out the last couple of 100,000 years we've had coral reefs in the island of Barbados that are very much alike through time."
+
+Budget cuts at plant institutes and their gene banks pose the biggest threat to the world's crops, the architect of a massive seed-saving plan says
+Work has begun on an agricultural "Noah's Ark" designed to preserve the genetic diversity of the world's crops beneath the Arctic permafrost for thousands of years.
+Dr Cary Fowler is the mastermind behind the so-called doomsday vault which will be carved deep in the side of a mountain in the Svalbard archipelago, 1,000 kilometres from the North Pole. 
+Construction of the vault began this week.
+Built with top security, the A$4 million (US$3 million) depository will preserve around three million seeds representing all known varieties of the world's crops at sub-zero temperatures.
+Fowler is executive secretary of the Global Crop Diversity Trust, an international non-profit organisation that supports the world's most critical crop collections currently scattered among some 1,400 gene banks.
+According to him, the main threat to the world's crops is probably not a nuclear war. 
+Rather, it is annual budget cuts at plant institutes and their gene banks around the world, as well as the occasional power failure that thaws seeds so that they fail to germinate.
+"Of course there is also a risk of wars and other catastrophes wiping out a whole institute. But in most cases there are no big headlines when a variety is irrevocably lost," he says.
+Convincing the world of the problem hasn't been easy, Fowler says. 
+"But people get a perception of the magnitude of the loss when I tell them that at the end of the 1800s, 7,000 named apple varieties were grown in the United States," he says.
+"Now, 6,800 of those are as extinct as the dinosaurs."
+Genetics of disaster
+Fowler, who earned a PhD in social sciences at Sweden's Uppsala University, says his life changed in the early 1970s when he read a paper by botanist Jack Harlan, entitled Genetics of Disaster.
+Harlan was a plant explorer, geneticist and breeder who understood crops, their origins and their use in sustaining mankind.
+His seed collections from 35 countries are stored in gene banks throughout the world. Some samples have been returned to their home countries after they were lost from local gene banks. 
+His work inspired Fowler. 
+"What we will store on Svalbard is not just one or two million seed samples and germ plasm, but the work of countless generations of farmers for thousands of years," Fowler says.
+"Our crops are the oldest artefacts in the world, they are older than the pyramids, and they are alive."
+No nation has ever maintained a prosperous food system based on genetic resources of purely indigenous origin. 
+"Today maize, a native of Central America, is the predominant food crop in southern Africa. ... Soybean, a species from China and East Asia, is now a major crop in the US and Brazil," Fowler says.
+Lessons from the potato famine.
+The best-known case of a crop almost wiped out is the 19th century Irish potato famine, which led to more than a million deaths. 
+The country had relied on only one variety of one crop for its staple food, and that variety had no resistance to disease. 
+"There wasn't enough genetic diversity to provide protection," Fowler says.
+"Without being able to go back to the many wild species and to the hundreds of farmers' varieties from Latin America, none of us would be eating potatoes today."
+The road to the Svalbard vault was a long and bumpy one, but Fowler has played a major role at each stage, from inventories of plant resources to resolving ownership issues. 
+"This is the only major problem in the world right now that I say, with a straight face, 'We can actually solve this!' "He says.
+"This is the one major problem we can fix, put on the back burner and move on to something else'." 
+The Trust will work closely with the United Nations Food and Agriculture Organisation to help support gene banks around the world, which will remain the first line of defence. 
+"But the more I see of the various threats to crop diversity, the better I feel about Svalbard," Fowler says.
+"In 100 or 200 years the Norwegian government of today may not be remembered for anything else than building the vault on Svalbard. Such are the immense implications of the vault for the world."
+
+The future looks a bit brighter for the giant panda
+There are many more giant pandas than previously thought, say scientists who have been studying DNA in panda faeces. 
+Professor Michael Bruford of the Cardiff University School of Biosciences and Professor Fuwen Wei of the Institute of Zoology, the Chinese Academy of Sciences led the study which is reported in the current issue of the journal Current Biology. 
+The giant panda is one of the world's most elusive and endangered species. 
+The traditional way to estimate panda populations is to examine the faeces for the length of bamboo it contains, Bruford says. 
+Researchers would then guess the panda's age and estimate how many different pandas the faeces had come from. 
+Bruford says say the new method provides more accurate estimates of panda populations.
+"Without DNA profiling you are bound to under-estimate," he says. 
+Bruford's team surveyed 26 square kilometres of a Chinese reserve. 
+"We really combed the reserve. There were teams of people in a field walking in a line," he says. 
+It was previously thought that 27 giant pandas lived there. But Buford's team now thinks there are 66.
+Researchers urge against complacency
+He predicts that the results would be replicated in other panda reserves. 
+"Our results found that previous surveys underestimated the population by more than 50%," says Bruford. 
+"These findings indicate that the species has a much better chance of long-term viability, although we must not become complacent, since the population size is still perilously low." 
+Bruford warns: "We still may be only talking about a few thousand individuals. These guys are not common." 
+Giant pandas' traditional homes have been the mountains of central and southern China, as well as Myanmar and Vietnam.
+But their numbers have fallen to only around 1,590, according to Chinese estimates, as their natural habitats have been destroyed by humans. 
+China founded its first nature reserve for giant pandas in the 1950s and now has 56 nature reserves for them, according to the Xinhua news agency. 
+It also has 183 giant pandas in captivity, while others have been sent to zoos around the world.
+
+Hwang Woo-Suk
+South Korea's disgraced cloning expert Hwang Woo-Suk went on trial this week on fraud, embezzlement and ethical charges related to his faked stem cell research.
+Hwang, once referred to as South Korea's "supreme scientist", was indicted on May 12 with five other scientists on charges in connection with the bogus research and the disappearance of millions of dollars in donations. 
+During the hearing, prosecutors accused Hwang of fabricating research data to obtain millions of dollars in funds. 
+"This is a unique fraud case in the academic world. He deceived our people and the world and embezzled research funds by using fabricated data," they said in a statement.
+Some 100 supporters of Hwang disrupted the hearing with boos and shouts despite the presence of dozens of police inside and outside the court. 
+Several times presiding judge Hwang Hyon-Joo had to call the hearing to order and demand silence from the public. 
+Apology
+Hwang apologised through his lawyer while admitting he was partly responsible for the fradulent stem-cell research featured in the 2004 and 2005 papers published in the US journal Science. 
+"Hwang neglected his duty to oversee his research team," the lawyer said. 
+Hwang, 52, became a national hero when he claimed that he had created 11 patient-specific stem cells in landmark research on cloning. 
+But a panel of experts at Seoul National University, where Hwang worked as a professor, concluded in January that the stem-cell claims were bogus. 
+Prosecutors said they had confirmed that Hwang's claims regarding stem cells were fraudulent. 
+Specifically, they confirmed the academic panel's conclusion that no cloned stem cells of any kind were ever created by Hwang. 
+If convicted on all charges, Hwang could face up to five years in prison, legal experts said. The trial is expected to wrap up next month. 
+Stem cells are master cells that have the potential to develop into any organ of the body. Scientists believe they could be used to fight illnesses including cancer, diabetes and Alzheimer's disease.
+
+A breast cancer cell: around 5% to 10% of breast cancers are inherited
+A new gene has been identified that can greatly raise the risk of breast cancer in women of European heritage, say researchers.
+A team at Iceland's biopharmaceutical company, deCODE Genetics, in Reykjavic reports their finding in the online journal Public Library of Science Medicine.
+It says the new gene, called BARD1, works in tandem with the well-known BRCA1 and BRCA2 genes to raise the risk of breast cancer by as much as 80%.
+"The BARD1 variant works together with the BRCA2 mutation in Iceland and increases the likelihood of breast cancer from 45% in those who have only the BRCA2 mutation up towards 100% in those who also have the BARD1 variant," says deCODE chief executive Kari Stefansson. 
+And women with the BARD1 variant who develop breast cancer are more likely to have tumours in both breasts, Stefansson said. 
+Cancer genes
+Breast cancer is known to run in families and has a genetic component, although most cases occur in people with no family history of the disease. 
+Several genes are known to be involved, including the BRCA1 and BRCA2 genes, p53 and others. 
+The known BRCA1 and BRCA2 mutations only account for about 3% of all cases of the disease. 
+The deCODE team is trying to find other genes that work with these genes.
+They found 1,090 women in Iceland who had breast cancer, and compared them to 703 Icelandic women who did not. The company has a database carrying the genetic profiles of virtually everyone in Iceland.
+A certain BARD1 mutation was found in 5.4% of breast cancer patients and 3.1% of women who did not have breast cancer - an 80% increase in risk, the researchers say. 
+Simply having the BARD1 mutation was not especially dangerous to a woman, but women who had it and a specific mutation on BRCA2 had a "dramatic" risk of breast cancer, the researchers say, adding it may be worth developing a test for that particular combination. 
+Many on the research team are employees of deCODE Genetics and/or have stock or equity interests in the company.
+Mutation in Italian and Finnish families too
+This BARD1 mutation has been found in Italian and Finnish families with a history of breast and ovarian cancer.
+It has not been found in people of Chinese, Japanese, African-American and Yoruban descent, the researchers add. 
+"Therefore, the variant may be restricted to individuals with European ancestry and could contribute to the higher load of breast cancer seen in this group," they say.
+"However, other BARD1 variants have been discovered in African-American and Japanese individuals. The contribution of these variants to the risk of disease is still uncertain." 
+Breast cancer is the second leading cause of cancer deaths among women after lung cancer, affecting 1.2 million women globally and killing more than 400,000 every year, according to the International Agency for Research on Cancer.
+
+Tiny cleaner fish grooming a large client fish
+Fish who visit mobile 'cleaning stations' to get their parasites removed, check out the cleaner fish on duty first to make sure they get the most trustworthy fish for the job.
+Dr Alexandra Grutter and colleagues from the University of Queensland's School of Integrative Biology report their experiments with the Great Barrier Reef coral reef cleaner fish (Labroides dimidiatus), in today's issue of the journal Nature.
+A cleaner fish spends most of its day eating parasites off other 'client' fish.
+But cleaners are tempted to cheat at their cleaning job because they would much rather eat the sticky mucous lining that covers their clients, instead of the parasites.
+So how do client fish get cleaner fish to eat against their natural food preference and establish a cooperative cleaning-feeding service?
+Grutter says the answer lies in the fact that client fish watch cleaners while they are with other clients to see who is doing a good job to judge who to use themselves.
+Fish care about their image
+Grutter used an aquarium-based experiment in which client fish were offered the choice of interacting with two cleaner fish: one that displayed parasite-eating behaviour, and one that did not. 
+Given the choice between two such cleaners, clients preferred to spend time close to the parasite-eating cleaner. 
+And cleaner fish were more likely to do the right thing when they were being observed by other clients than when they were alone with one client. 
+The researchers think the client fish build up a social image of the cleaners they observe, and choose to allow those that score highly to feed on them.
+Grutter says cleaners learned to be more cooperative when they were having their image scored, compared to when they weren't.
+"These results explain why cleaner fish feed against their preference," she says.
+The finding shows that complex social networks exist in the aquatic world, and helps set the stage for the evolution of altruism and reputation, the researchers say.
+
+Landsat image of Salton Sea and Coachella Valley, Southern California - the southern San Andreas fault is shown in red 
+The notorious San Andreas fault has enough pent-up energy to create a massive quake, says one seismologist, although he is not sure when the big one will occur.
+Professor Yuri Fialko, of the Scripps Institution of Oceanography at La Jolla, California, reports his findings in today's issue of the journal Nature.
+"The fault is accumulating stress at a high rate, but this does not suggest that a rupture is imminent," says Fialko. "When the quake will happen nobody knows." 
+The San Andreas runs north-south along almost all of western California, passing through San Francisco and running just north of Los Angeles, before emerging in the far south in the San Jacinto fault. 
+The land on western side of the San Andreas is heading north, while the eastern side is heading south - a movement called slip. 
+But slip, between mighty opposing plates, is a rarely a smooth affair. 
+The pent-up friction, when released, can cause cataclysmic earthquakes. But the threat can be eased if the energy is released in minor movements, known as creep. 
+The northern segment of the fault produced the San Francisco Earthquake in 1906, and the central segment had a big quake in 1857. 
+But the southern segment has not produced a great earthquake for at least 250 years, so the big question is when the next "big one" will occur there. 
+Satellite images
+Fialko looked at the critical question of creep in the southern section. 
+He used satellite imaging from two European Space Agency satellites and data from GPS monitors deployed on the ground to get a picture of surface movement in this area from 1985 to 2005. 
+Fialko says his data is more complete than that used in previous studies because measurements were taken every 20 metres instead of at ground stations 10 kilometres apart.
+Sadly, for the 18 million people of the Los Angeles region, he has only bad news to offer. 
+
+Interestingly, the study found testosterone levels did not explain the differences between male and female war-mongering
+The first scientific proof that men who are over-confident and narcissistic are more likely to start wars, has been published this week.
+But such men are also the most likely to lose wars, the study found.
+A team led by Dr Dominic Johnson of Princeton University in New Jersey, report their findings online ahead of print publication in the Royal Society journal  Proceedings B.
+They recruited 200 men and women in an unusual experiment aimed at exploring whether a bias towards optimism may drive a leader to start a war. 
+The volunteers were asked to play a one-on-one computer game. 
+Each played the role of the head of a fictitious country that is in conflict with a neighbour over a vast field of diamonds on a disputed border. 
+Players were each given US$20 for taking part, but earned an additional bounty of $10 per game if they won, either by amassing the most wealth or by defeating their opponent. 
+Before the game, each player was asked to rank himself or herself, predicting how he or she would fare against the 199 others. 
+In the game, each player was given a virtual treasure chest of US$100 million, which they could spend on upgrading their military, investing in industrial infrastructure or keep in reserve as cash.
+As the game unfolded, the player was given updates about his opponent's actions. 
+Players could negotiate deals in which they could get access to the disputed diamonds, thus adding to their wealth, but they also had the option of waging war at any time and without provocation.
+Victory in war would be determined by how much they had spent on their military, but there was an element of chance, too - the computer equivalent of a roll of the dice. 
+Males five times more likely to attack
+More than 1,000 decisions were taken by the players during six rounds of the games. Of these, 70% involved negotiation (something that could be done both during peace and during a war); 20&nbsp;% involved doing nothing; 6% involved fighting; and 4% to make a threat. 
+Wars occurred in almost half of the games.
+Individuals who launched unprovoked attacks were more than five times likelier to be a male than female. 
+And they were big on self-confidence, too. On average, a warmonger ranked himself 60 out of the 200 players, whereas those who tried to avoid war ranked themselves more humbly, at 75 on average.
+Testosterone levels
+Contrary to popular belief, though, testosterone was not a key factor. 
+The players gave a saliva test before the game, and these showed there was no significant difference in male hormone levels between warmongers and peaceniks.
+On the other hand, there was a clear psychological characteristic among the warmongers. After the game, they were given a personality assessment, which found high levels of narcissism among the men - but not among the women. 
+The researchers' theory is that humans have a built-in bias towards optimism because it is a survival mechanism. By encouraging hope, called "positive illusions," our distant ancestors could cope with adversity, strengthen their resolve and bluff their opponents.
+But the question is when "positive illusions" become over-confidence - and the impact that this can have in modern-day society, on a president or a prime minister who believes that a war, despite its risks, can be won quickly and easily.
+Ironically, the higher the self-ranking, the lower the actual performance, Johnson's team found. 
+"Those who expected to do best tended to do worst," the researchers say. "This suggests that positive illusions were not only misguided, but actually may have been detrimental to performance."
+
+It might be a prehistoric phenomenon but human destruction of wetlands has been faster in the last 300 years, the researchers say
+Human damage to coastal ecology is not a recent phenomenon, say an international team of scientists: it's been happening since the dawn of civilization.
+Whether they settled along the coasts of North America, Europe or Australia, humans have always been reducing the biodiversity of estuaries and coastal seas, say researchers publishing in today's issue of the journal Science.
+"This isn't a blame game," says Roger Bradbury, an adjunct professor at the Australian National University and co-author of the paper.
+"People in the 20th century haven't started to do this - we've just built on what our ancestors have done."
+The upshot has been a depletion of more than 90% of formerly important species, destruction of more than 65% of sea grass and wetlands, and degradation of water quality, the scientists say.
+The team used detailed information from 12 different estuary and coastal ecosystems across the globe to build a picture of what they would have looked like before humans arrived on the scene.
+Using mathematical models, they created a timeline for the changes that would have taken place in the numbers of different plants and animals.
+These models revealed that all 12 different ecosystems would have undergone the same general trajectory of change - a long period of slow decline followed by 150 to 300 years of rapid degeneration.
+"It's just the quickening of economic growth and development," says Bradbury. 
+"Everything's quickened up - the population has grown and we cycle through things faster now. Plus we have greater control over the world than our ancestors."
+By depleting the living creatures in estuaries, we've also had an impact on physical aspects of the ecosystems, the scientists say. 
+Recent disasters like the 2004 Asian tsunami and last year's hurricane Katrina were made worse by the loss of mangroves and wetlands, they say.
+"The whole thing about estuaries is that you're at the interface between sea and land," Bradbury says. 
+"When you tamper with the living things, you have an impact on physical structures."
+On a positive note, the scientists report that conservation efforts in the 20th century have had some impact. 
+They led to a partial recovery for 12% of species, and a substantial recovery in 2% of
+species, particularly for animals like seals, otters, birds and crocodiles.
+"Things are grim in many estuaries around the world, but we know enough now to turn things around," Bradbury says. "If we start now, we have a reasonable chance of restoring them."
+"This isn't magic," he adds. "It's hard work."
+
+The beads were made from these type of shells
+Human culture developed slowly in northern Africa and the Middle East rather than bursting forth in Europe, suggest scientists, who have discovered what may be the oldest shell beads dating back 100,000 years.
+Dr Francesco d'Errico of the National Centre for Scientific Research in Talence, France and colleagues report their findings in today's issue of the journal Science.
+Until recently, researchers generally believed the first cultural signs emerged 40,000 years ago when modern humans appeared in Europe. 
+But d'Errico and colleagues say the new shell beads, from Israel and Algeria, were made for decorative purposes and show progress came much earlier in northern Africa and the Middle East. 
+"Modern humans in Africa developed behaviours that are considered modern quite early in time," says d'Errico. 
+"These people were probably not just biologically modern but also culturally and cognitively modern." 
+Jewellery and other forms of personal decoration were one of the most important early expressions of human culture, says study coauthor Dr Marian Vanhaeren of University College London. 
+Searching museum collections
+The researchers say that, searching through museum collections, they found bead-like shells with holes in them from sites in Skhul, Israel and Oued Djebbana, Algeria. 
+These were similar to shell beads dating back 75,000 years found in a previous study by d'Errico and Vanhaeren in South African caves. 
+These South African shells are now firmly believed to be decorative beads, the study says. 
+To be certain, the researchers say they wanted to find beads from more than one site in the same region dating to the same period, to confirm that bead working was underway earlier than previously thought. 
+"It's very important to establish the chronology of these modern types of behavior, and this paper constitutes we think a significant advancement," d'Errico says. 
+Dating the shells
+Archaeologists excavated Skhul in the early 1930s using less meticulous methods than archaeologists use today, so the researchers had to do some additional work to determine exactly where the shells came from and how old they were. 
+One of the site's sediment layers contained a series of human skeletons, which recent dating efforts placed at 100,000 to 135,000 years old. 
+Coauthor Dr Sarah James, a researcher at the Natural History Museum, London, where the Skhul specimens are kept, analysed the crust of sediment stuck to one of the two shells and found that the shells came from the same sediment layer that the skeletons did. 
+The shells, Nassarius gibbosulus, are scavenging marine snails that live in shallow waters and are now only found in the central-eastern Mediterranean. 
+The relatively large size of the shells from Skhul and Oued Djebbana also seems to confirm their old age, since this species of snail was bigger 100,000 years ago than it is today, the researchers say. 
+Oued Djebbana was excavated in the late 1940s. Currently just a single radiocarbon date is available, indicating that the site is more than 35,000 years old. 
+Based on the technology and style of the stone tools found there, however, the site could be up to 90,000 years old, the researchers say. 
+The sample size is small, but the researchers argue that Skhul and Oued Djebbana are so far from the sea - 200 kilometres in case of Oued Djebbana - that the shells must have been intentionally brought there, most likely for beadworking. 
+By studying modern Nassarius shells from Mediterranean beaches, they also determined that shells with single holes in the centre are rare in nature and that Skhul and Djebbana inhabitants must have purposely perforated or deliberately picked out such shells, arguably for symbolic use.
+
+Could our perpetual childishness actually cause genetic changes?
+Grown-ups today are more immature than ever, according to research showing that increasing numbers of adults are retaining behaviour and attitudes normally associated with youth.
+As a consequence, many older people simply never achieve mental adulthood, says evolutionary psychiatrist Bruce Charlton from the School of Biology at the University of Newcastle upon Tyne, England.
+Among scientists, the phenomenon is called psychological neoteny.
+Charlton, who is also editor-in-chief of Medical Hypotheses, which will feature a paper outlining his theory in an upcoming issue.
+Charlton says humans have an inherent attraction to physical youth, because it can be a sign of fertility, health and vitality.
+A symptom of instability?
+In the mid 20th century, however, another force kicked in, with an increasing trend for individuals to change jobs, learn new skills, move to new places and make new friends.
+A "child-like flexibility of attitudes, behaviours and knowledge" is probably adaptive to the increased instability of the modern world, Charlton believes.
+Formal education now extends well past physical maturity, leaving students with minds that are, he says, "unfinished".
+"The psychological neoteny effect of formal education is an accidental by-product, the main role of education is to increase general, abstract intelligence and prepare for economic activity," he says.
+"But formal education requires a child-like stance of receptivity to new learning, and cognitive flexibility."
+"When formal education continues into the early twenties," he says, "it probably, to an extent, counteracts the attainment of psychological maturity, which would otherwise occur at about this age".
+Genetic changes
+Charlton says past cultures often marked the advent of adulthood with initiation ceremonies.
+While the human mind responds to new information over the course of any individual's lifetime, Charlton argues that past physical environments were more stable and allowed for a state of psychological maturity.
+In hunter-gatherer societies, that maturity was probably achieved during a person's late teens or early twenties, he says.
+"By contrast, many modern adults fail to attain this maturity, and such failure is common and indeed characteristic of highly educated and, on the whole, effective and socially valuable people," he said.
+"People such as academics, teachers, scientists and many other professionals are often strikingly immature outside of their strictly specialist competence in the sense of being unpredictable, unbalanced in priorities, and tending to overreact."
+Charlton added that since modern cultures now favour cognitive flexibility, "immature" people tend to thrive and succeed, and have set the tone not only for contemporary life, but also for the future, when it is possible our genes may even change as a result of the psychological shift.
+Cultural shallowness
+The faults of youth are retained along with the virtues, he believes.
+These include short attention span, sensation and novelty-seeking, short cycles of arbitrary fashion and a sense of cultural shallowness.
+At least "youthfulness is no longer restricted to youth," he says due to overall improvements in food and healthcare, along with cosmetic technologies.
+David Brooks, a social commentator and an op-ed columnist at The New York Times, has documented a somewhat related phenomenon concerning the current blurring of "the bourgeois world of capitalism and the bohemian counterculture," which Charlton believes is a version of psychological neoteny.
+
+A computer that can decipher your emotions could help online advertisers target you at times when you're most likey to be receptive to their message
+Your computer may soon be able to tell what you're thinking by picking up on expressions like a raised eyebrow, a nod of the head or an angry glare, scientists say.
+British and American researchers are developing an "emotionally aware" computer that will be able to read an individual's mind by analysing a combination of facial movements that represent feelings.
+The technology will be unveiled at a science exhibition in London today. 
+"The system we have developed allows a wide range of mental states to be identified just by pointing a video camera at someone," says Professor Peter Robinson, of the University of Cambridge in England.
+He and his collaborators believe the mind-reading computer's applications could range from improving people's driving skills to helping companies tailor advertising to people's moods.
+"Imagine a computer that could pick the right emotional moment to try to sell you something, a future where mobile phones, cars and Web sites could read our mind and react to our moods," he says. 
+The technology is already programmed to recognise different facial expressions generated by actors.
+Robinson hopes to get more data to determine whether someone is bored, interested, confused, or agrees or disagrees.
+Visitors to the four-day exhibition organised by The Royal Society, Britain's academy of leading scientists, will be invited to take part in a study to hone the program's abilities.
+Encoding boredom, tiredness, confusion
+The scientists, who are developing the technology in collaboration with researchers at the Massachusetts Institute of Technology (MIT) in the United States, also hope to get it to accept other inputs such as posture and gesture. 
+"Our research could enable Web sites to tailor advertising or products to your mood," Robinson says.
+"For example, a webcam linked with our software could process your image, encode the correct emotional state and transmit information to a Web site." 
+It could also be useful in online teaching to show whether someone understands what is being explained and in improving road safety by determining if a driver is confused, bored or tired. 
+"We are working with a big car company and they envision this being employed in cars within five years," Robinson says, adding that a camera could be built into the dashboard. 
+Anyone who doesn't want to give away too much information about what they are feeling can just cover up the camera, he says.
+
+Lava flows from a super eruption half a billion years ago in Australia covered hundreds of thousands of square kilometres 
+Scattered rafts of black lava over northern and central Australia are really part of one gigantic volcanic field that appears to be one of oldest and largest on Earth, geologists believe.
+If so, the half billion year old eruption might be the culprit in the first mass animal extinction event in the history of life.
+Australian geologists used the chemical signatures of the far-flung basalt lava rocks and their ages to connect them to a single huge volcanic eruptive episode between 505 and 508 million years ago.
+The newly identified Kalkarindji Continental Flood Basalt Province covered at least 650,000 square kilometres with more than 190,000 cubic kilometres of lava, report geologists Dr Linda Glass and Dr David Phillips, who were at the Australian National University when the research was undertaken.
+Bigger than thought
+"It may be a lot larger than we think," Phillips says.
+He says since the paper appeared this month in the journal Geology he's been getting calls from other Australian  geologists who say they know of even more distant pieces of what could be the same mega lava deposit.
+Unlike episodic and hacking explosive volcanoes like Mount St Helens or Mount Pinatubo, flood basalts literally pour lava out onto the Earth's surface in often vastly greater quantities and over far longer periods, perhaps many hundreds of thousands of years, according to some geologists.
+That means they can cover a lot more ground.
+Younger recent flood basalts can be found mostly intact in places like the Columbia River region of the US Pacific Northwest.
+But at a half-billion years old, the Kalkarindji Continental Flood Basalts have been heavily eroded and buried, leaving only far-flung hints of its former glory.
+"This is part of a growing picture," says Paul Renne, director of the Berkeley Geochronology Center in California.
+Other large volcanic provinces have been identified in the same way.
+First in one area by a few geologists, then with a flurry of discoveries by other geologists who were working on other parts of the puzzle, but hadn't seen the larger context.
+Link to Cambrian mass extinction
+Two things make the Kalkarindji Continental Flood Basalt Province discovery special and robust, says Renne.
+One is that it's the oldest such lava formation dated using the very reliable Argon-40/Argon-39 analysis, and Phillips is one of the world's top "Argon-Argon" researchers, Renne says.
+But, Renne adds that chemical aging of the far-flung rocks makes the process of dating them slightly less reliable.
+The second thing is that the timing of Kalkarindji is right at the first major die-off of animals after they first exploded onto the scene about 535 million years ago during the Lower Cambrian Period.
+"That time span was when (animal) life on Earth really took off," says Phillips.
+"We have the mass proliferation of species."
+"Things just took off like wildfire," agrees Renne.
+Then at somewhere around 500 million years ago many of the strange new beasts were mysteriously wiped out.
+A massive release of lava could have caused such an event by releasing a lot of heat and climate changing gases into the atmosphere.
+
+Practitioners of feng shui say it can improve your living and working environmment. But does it also work for web pages?
+Chinese feng shui and the ancient Indian science of vaastu shastra can boost business by helping web designers create better pages, say experts who are marrying traditional philosophies with the internet. 
+Believers in vaastu shastra say the system seeks to create harmony between people, objects and the five elements of earth, fire, water, air and space.
+They say it can be directly applied to the web, just as it is to home design. 
+The philosophy of feng shui has also been used for centuries to bring balance and harmony between people and their environment.
+"Just as the world comprises of the five basic elements, each web site has five elements and these need to be in balance with one another," says Dr Smita Narang, author of Web Vaastu .
+The book has proved popular with businesses. 
+How it works
+"Earth is the layout, fire is the colour, air is the HTML, space is name of the web site, and water is the font and graphics," says Narang.
+He says each must be chosen carefully to strike a balance with the other.
+ Narang, a vaastu expert who has spent four years analysing around 500 sites, says a web site that disregards vaastu rules will have few hits and business will suffer.
+ An essential element of feng shui is the idea that unnecessary objects allow free flow of energy, followers say.
+They say this principle can also be applied to making better websites and generating more visits.
+A Web site where the colours hurt your eyes, the music offends your ears or has too much information is probably too cluttered and does not give a positive flow of ch'i," says Vikram Narayan, a Mumbai-based feng shui practitioner. 
+The trick, Narayan says, is to remove items on your web site that serve no purpose, and keep the things that serve you well. 
+Brijesh Agarwal of Indiamart, a company offering business solutions to small and medium-sized enterprises, says he has had mixed results on the five sites that his company has designed according to vaastu principles. 
+"We have found that on three sites the number of hits has increased by 60&nbsp;% but the other two sites have not been affected," Agarwal says.
+"I can't say for definite that the positive results are due to vaastu or due to increased marketing, but I hope that vaastu has helped."
+
+The conditions that determine whether a male will grow up gay may be present before birth, research suggests
+The last male child in a family of many boys is more likely to be gay than a boy who is born first or has fewer brothers, according to new research.
+The Canadian study, published in the US Proceedings of the National Academy of Sciences online journal, suggests that being gay starts in the womb.
+The study, led by Dr Anthony Bogaert of Brock University near Toronto, found that having older brothers increases a man's chance of being gay, even if the older brothers don't live with the younger sibling.
+Adopted or step brothers don't appear to have an effect.
+"The most consistent bio-demographic correlate of sexual orientation in men is the number of older brothers (one has) and not social influences," Bogaert reports. 
+"Only biological older brothers, and not any other sibling characteristic, including non-biological older brothers, predicted men's sexual orientation, regardless of the amount of time reared with these siblings." 
+There's no evidence that similar patterns apply to girls, he says.
+Fraternal birth order effect
+The results are a variation of the so-called "fraternal birth order effect" theory on homosexuality in men. 
+The researchers didn't investigate the mechanism at play, but Bogaert says his study indicates that biological, rather than social or child-rearing factors, are at play.
+One possible explanation is that during pregnancy a mother's immune system recognises male foetuses as foreign and creates "maternal anti-male antibodies".
+These antibodies could affect the part of the brain that determines sexuality.
+The effect is cumulative and therefore more likely to cause homosexuality in the last of several sons born to the same mother.
+"These results support a prenatal origin to sexual orientation development in men and indicate that the fraternal birth order effect is probably the result of a maternal "memory" for male gestations or births," he says.
+Female foetuses aren't affected because mothers are themselves female, so the mother doesn't create antibodies against daughters. 
+Bogaert reports that the age of the mother also appears related to the sexual orientation of her sons, "with homosexual men's mothers being significantly younger than the mothers of heterosexual men".
+Gay staircase effect?
+Professor Roger Short, a reproductive biologist in the faculty of Medicine at Melbourne University, says there could be a social element in younger brothers with lots of older male siblings becoming gay.
+"I wouldn't be surprised if you come from a large unisex family where you're one boy amongst many, and the last in the line, that you've got a slightly socially deprived environment," he says.
+"That could make you more aligned with ... the same sex because you'd be so ignorant and terrified about the opposite sex."
+But he says while having a female "sandwiched" between two males in utero can have a masculising influence in species like rats and mice, there's no biological evidence for Bogaert's theory of maternal antigens producing gay boys.
+"No one's ever suggested that maternal antibodies to something produced by a male foetus could have a long lasting effect to act on subsequent male foetuses," he says.
+"So each subsequent male foetus would be a little more gay than the one before it.
+"You would have a sort of gay staircase effect."
+
+New technology aims to convert footsteps into renewable energy
+Vibrations from passing trucks, the rumbling of speeding trains and even the footfall of busy city commuters could be captured and converted into energy to light walkways and buildings, engineers say.
+A London-based architectural firm is working on a project that aims to harness the pulse of a city and use it as a renewable energy source.
+Facility Architects director Clair Price says tens of thousands of people can pass through urban hubs like train stations during rush hour.
+"You don't need to be a maths genius to realise that if you can harness that energy... you can actually generate a very useful power source that is currently being wasted," she says.
+Price's team has financial and technical support from several organisations for the proposal.
+"My first reaction when I saw it was wow, this is fantastic," says Tony Bates, business development manager at Scott Wilson, an engineering consultancy firm based in the UK.
+"As an engineer of course, you can really see that this can really work."
+Bates and Price are now in the process of developing a joint partnership to make the idea a reality.
+The architectural team is working with university research groups to finish two vibration-harvesting prototypes by December.
+Good vibrations
+The first is a staircase that will contain hydraulic or piezoelectric technology in the risers.
+The technology will pick up kinetic energy from commuter footfalls and convert it into an electrical current.
+Climbing stairs requires more force, which means there's more energy to be tapped.
+Engineering experts from the University of Hull hope to develop a system that will convert at least 50% of the six to eight watts each person typically generates while walking.
+The current will be stored in a battery, which can be used to provide energy for lighting or electronic devices.
+The second prototype is a wireless lighting system that will use tiny generators with components designed to resonate at the same frequency as surrounding vibrations.
+The resonance will either move a magnet relative to a coil or put stress on a crystalline structure inside a generator to produce a current.
+Light-emitting diodes connected to such vibration harvesters could illuminate the underside of arches.
+
+The double vortex at Venus' south pole
+Venus has a bizarre double vortex that whirls in the atmosphere above its south pole, a new mission to the planet has found.
+The unmanned Venus Express spacecraft spotted the "double eye", formed by winds of super-hurricane force, in its very first swing around Venus, says the European Space Agency (ESA).
+The Venus Express pictures also show the presence of a collar of cold air around the vortex structure, possibly due to the recycling of cold air downwards.
+Previous missions to Venus have spotted a similar structure over the planet's north pole and glimpsed at stormy atmospheric behaviour at the south pole. 
+The winds on Venus spin westwards at hundreds of kilometres per hour, taking only four days to complete the rotation of a planet that is just under the size of Earth. 
+This "super-rotation," combined with the natural recycling of hot air in the atmosphere, would logically induce a vortex over each pole, but the mystery is why there should be two vortices. 
+"We still know very little about the mechanisms by which the super-rotation and the polar vortexes are linked," says Dr H&aring;kan Svedhem, the mission's project scientist. 
+"Also, we are still not able to explain why the global atmospheric circulation of the planet results in a double vortex and not a single vortex," he says.
+"Atmospheric vortextes are very complex structures that are very difficult to model, even on Earth."
+Venus Express is Europe's first dedicated mission to Earth's closest planet. 
+It went into elongated orbit around Venus on 11 April, equipped with scanners aimed at deciphering the enigmatic Venusian atmosphere. 
+The elongated orbit, lasted 9 days and ranged between 350,000 and 400 kilometres from Venus' surface
+Since 7 May Venus Express has been circling the planet in its final 24-hour orbit, ranging between 66,000 and 250 kilometres from Venus.
+The planet seems to have a case of runaway global warming, and understanding the mechanisms that drive this could be of use in dealing with climate change on Earth.
+Venus's mean surface temperature is 457&ordm;C - hot enough to melt lead and even hotter than Mercury, the closest planet to the Sun. 
+Its atmosphere is 96% carbon dioxide, with yellowish clouds of sulfur and sulfuric acid droplets.
+
+A new tool for world peace?
+Video games can help save the world by raising awareness of the world's downtrodden, a group of socially conscious game designers say.
+The creators of free educational games such as "Darfur is Dying" and "PeaceMaker" met with humanitarian activists at The New School university in New York this week for the third Games for Change annual conference. 
+The idea is to use video games to educate youth about real-world issues - fighting poverty, surviving in war-torn Sudan and negotiating Middle East peace. 
+And while there is violence in the games, it is being perpetrated by real-life players such as warring countries, not by the person playing the game. 
+"It's the next generation of activism," says Stephen Friedman, general manager of MTVu, a television network owned by cable channel MTV aimed at college students that created a grant program encouraging educational games. 
+"Given this generation lives online, it's heartening to see them using this incredibly powerful medium in a very potent way," Friedman says.
+Gaining popularity
+The idea appears to be gaining popularity. 
+"Darfur is Dying," which allows players to avoid being killed in violence-plagued Sudan, was downloaded more than 750,000 times in the past two months.
+"Food Force," created by the World Food Programme at the United Nations, has been downloaded off the internet more than 2 million times. 
+Just 40 developers and activists attended the first Games for Change conference in 2004. About 250 people participated this year. 
+Large gaming companies have expressed some interest in the market's potential, Bob Kerrey, the president of The New School and a former US senator from Nebraska, says.
+"I do see some glimmers of reason to be optimistic that games ... can be used to accomplish educational missions and improve people's quality of understanding of what's going on in the world," Kerrey says. 
+"The question for us ... is how do I use it to accomplish something good?" 
+In the shoes of a refugee
+"Darfur is Dying" puts players in the shoes of a Sudanese refugee. Plunked down in the middle of the violence, players must make it to a water well and try to survive for seven days in a camp besieged by militia.
+In "PeaceMaker," players take the role of either the Israeli prime minister or the Palestinian president and try their hand at situations ranging from diplomatic talks to responding to military attacks. 
+PeaceMaker co-creator Eric Brown says he hopes to usher video games into a new socially conscious arena. 
+"We believe in the power of interactive media and we think it has a lot of positive potential," says Brown, a Carnegie Mellon University graduate student. 
+"Just by putting someone in the shoes of the other side, they may think of a perspective they might not have thought of before."
+
+The feeling of being watched make us do the right thing, researchers have found
+Forget about installing closed-circuit surveillance cameras - a simple, low-cost defence against thieves and freeloaders may be a photocopy of a pair of eyes. 
+Behaviour researchers at the Newcastle University in the UK conducted a sly experiment on their colleagues and found that people were encouraged do the right thing when they were being 'watched' by a pair of eyes on a poster.
+The study, by Dr Melissa Bateson and team, is believed to be the first to test how cues of being watched affect people's tendency for social co-operation in a real-life setting.
+The study is reported online ahead of print publication in the Royal Society's journal Biology Letters.
+Honesty box
+For their experiment, Bateson and her colleagues made use of a long-running 'honesty box' arrangement in a common room used by around 48 staff in the university's psychology department.
+Academics were asked to put money in the box for any tea, coffee and milk they used without anyone checking to see whether they were actually doing so. 
+The honesty box had been operating for many years, so users had no reason to suspect an experiment was taking place. 
+Over 10 weeks, the researchers placed a poster above the honesty box listing prices of tea, coffee and milk. 
+The poster also featured an image banner across the top that alternated each week between different pictures of flowers and eyes. 
+The eye pictures varied in the sex and head orientation but were all chosen so that the eyes were looking directly at the observer. 
+Each week the research team recorded the total amount of money collected and the volume of milk consumed as this was considered to be the best index available of total drink consumption. 
+The team then calculated the ratio of money collected to the volume of milk consumed in each week. 
+The eyes have it
+On weeks when the "eyes" image was shown, takings were 276% higher than during the "flower" weeks. 
+"I was really surprised by how big the effect was as we were expecting it to be quite subtle but the statistics show that the eyes had a strong effect on our tea and coffee drinkers," says Bateson.
+The researchers say the study suggests that humans are "strongly attuned" to subconscious cues about behaviour that could damage their reputation. 
+"Our brains are programmed to respond to eyes and faces whether we are consciously aware of it or not," says Bateson.
+The researchers say that being seen to co-operate is a good long-term strategy for individuals because it is likely to mean others will return the gesture when needed.
+"Our findings suggest that people are less likely to be selfish if they feel they are being watched, which has huge implications for real life," says Bateson. 
+"For example, this could be applied to warnings about speed cameras. A sign bearing an image of a camera would have to be actively processed by our brains, as it is an artificial stimulus. Our research and previous studies suggest drivers would react much more quickly and positively to natural stimuli such as eyes and faces." 
+The group now hopes to expand the study to involve a larger sample population.
+
+As oil reserves dwindle, it is being suggested we could use underground explosions to increase the permeability of rocks and make it easier to extract the remaining oil
+Creating artificial seismic waves, similar to those that occur during an earthquake, could help squeeze more oil from natural reservoirs, say scientists.
+Dr Emily Brodsky of University of California, Santa Cruz and colleagues report their findings in today's issue of the journal Nature.
+"Shaking increases permeability," says Brodsky, an assistant professor of earth sciences.
+"Permeability governs how fluid flows through rock, whether it's water or oil, so this has practical implications for oil extraction," she says. 
+Brodsky and colleagues also found that the amount of permeability is directly related to the amplitude of the shaking. 
+"Potentially if you could increase permeability you could greatly increase the available oil you could tap out of a reserve," she says. 
+One way of doing that, in principle, is by mimicking the effects of an earthquake, using, for example underground explosions.
+"If we understood the physics of the permeability enhancement well enough, the vibrations could be tuned to increase with the flow of oil," Brodsky says.
+Clues from water seepage
+The scientists made their discovery after studying 20 years of data of water seeping in and out of wells during seven earthquakes in an area of California. 
+They found that water levels in the wells rose and fell gradually according to local weather and rainfall.
+But superimposed on these long-term trends were regular, daily variations of a few centimetres owing to the 'solid Earth tides'.
+As the motion of the Moon around the Earth makes local sea levels rise and fall tidally each day, so this and the Earth's rotation causes tidal 'squeezing' of the solid Earth. 
+The effect is tiny, but it squeezes the porous rock of the aquifer that feeds the wells, pressurising the water held in the pores and forcing regular changes of up to 3 centimetres in the well water.
+As the squeezing subsides, well water flows back into the aquifer.
+But how quickly this happens depends on the permeability of the rock.
+The team noticed that every time an earthquake occurred the permeability jumped and the surrounding rocks became up to three times more permeable.
+A few months after the tremor the rocks relaxed back into its original state and permeability returned to normal levels. 
+The scientists are planning more studies to better understand what aspects of the shaking makes the permeability increase.
+They are also interested in studying how seismically induced changes in fluid flow within geological faults might trigger further earthquakes.
+
+NASA says another major incident in launching the space shuttle would cast doubts on the program
+NASA is ready for a second - and likely last - attempt to recover from the 2003 Columbia disaster and resume construction of the half-built International Space Station.
+After more than three years and US$1.3 billion since the Columbia accident, the countdown has begun for the launch of the space shuttle Discovery at 5:49 am Sunday Australian Eastern Standard Time.
+"Everyone's been excited and kind of anxious to get into a launch countdown," NASA test director Jeff Spaulding said at a press conference this week. "They've worked hard to get us to this point."
+NASA's chief says it's time to move, despite objections from key safety and engineering officials who unsuccessfully argued for additional modifications before Discovery flies.
+NASA administrator Mike Griffin acknowledges he is taking a chance, but not with the lives of the astronauts, who could stay aboard the station for nearly three months while they wait for a new ride home if Discovery should suffer Columbia-like damage during its liftoff.
+In 2003 Columbia was struck by a chunk of foam weighing nearly a kilogram that fell off its external fuel tank and smashed into its left wing. 
+The damage was undetected until after the shuttle broke apart as it flew through the atmosphere for landing 16 days later. All seven astronauts aboard died.
+Some foam loss still expected
+Last year, NASA flew its first mission since the accident, testing not only a new tank design, but also a myriad of inflight inspection techniques, heat shield repair materials and other safety improvements. 
+Large pieces of foam insulation again fell off the tank and the fleet was grounded again.
+NASA still expects some foam loss, particularly from areas that cover metal brackets holding pressurisation lines and a box of cables to the outside of the tank. 
+But any flyaway foam is expected to be too small to do damage, shuttle managers said.
+With the fleet's 2010 retirement date looming and plans to build a new vehicle to transport crews and cargo to the station and eventually the moon, NASA has neither the time nor money to handle more serious shuttle problems.
+"If we have another major incident in launching the space shuttle, I would not wish to continue with the program," Griffin said.
+Equipment and supplies
+Launching will be only the beginning. 
+The shuttle is scheduled to dock at the space station two days later to deliver more than 2,000 kilograms of equipment and supplies, as well as a new crewmember, European astronaut Thomas Reiter.
+The station has been operating with just two-man crews since Columbia's demise to save on supplies while the shuttle, which delivers the bulk of the station's cargo, was grounded.
+The most critical equipment includes replacement parts for the station's mobile transporter, which was shut down after it inadvertently severed a set of cables that provide power, video and data. 
+Without the transporter, which is a small cart that runs along tracks on the outside the station to move equipment to various work sites, station assembly cannot continue.
+One of up to three spacewalks planned during the flight is devoted to repairing the transporter. 
+Astronauts Piers Sellers and Michael Fossum are also scheduled to test an extension to the shuttle's 15-metre-long robotic arm to see if it is stable enough to serve as a work platform for emergency inflight heat shield repairs on currently inaccessible parts of the shuttle.
+
+The study showed children who stuttered showed greater emotional "reactivity" to everyday stresses, like having a toy taken away
+Preschoolers who stutter may have more difficulty controlling their emotions than other children their age, a study has found - suggesting that emotional factors contribute to the speech disorder.
+Dr Edward Conture, a US professor of hearing and speech sciences at Vanderbilt University in Nashville and colleagues will report their findings in the Journal of Communication Disorders.
+Stuttering is a common speech problem that typically becomes apparent between the ages of 2 and 5 years old. Children may repeat or draw out words or parts of words, or have difficulty beginning a word.
+The exact cause of stuttering is unknown, but it probably involves a "complex interaction" between genes and environment, says Conture.
+Stuttering is believed to have a strong genetic component, as it often runs in families. 
+But it has also long been suspected that emotional development may contribute to the disorder, says Conture. 
+His team found that preschoolers who stuttered were typically more excitable than their peers with normal speech, and tended to have a harder time calming down or shifting their attention away from a stressful situation. 
+The findings are based on reports from parents of 65 preschoolers who stuttered and 56 children who did not. Both groups of parents completed a standardised questionnaire on child behaviour. 
+Three general differences between the two groups emerged, Conture says. 
+Children who stuttered showed greater emotional "reactivity" to everyday stresses, like having a toy taken away; it took them longer to settle down once they were excited or upset; and they were less adept at shifting their attention away from the stressor, often becoming fixated on it instead. 
+The researchers suspect that poor attentional control, leading to higher levels of emotional reactivity may contribute to the development of stuttering in children who are predisposed to the speech problem. 
+Findings support parents' observations
+Conture says the findings are in line with what parents often tell their child's doctor or speech therapist: that emotional outbursts or excitement seem to trigger stuttering episodes. 
+He says parents should tell their health care provider if they notice that their child regularly has strong emotional reactions to everyday challenges or changes in their daily routine. 
+Parents may be able to help their child by demonstrating ways to calmly cope with stressful situations, says Conture. 
+He also notes that children can have difficulty controlling not only negative emotions, but excitement over positive events as well; so it may not be a good idea, he said, to tell your child about a trip to somewhere exciting months beforehand. 
+No one knows yet whether helping children better regulate their emotions will aid their stuttering problems, but Conture says the current findings "tell us this is something we should look at." 
+He also emphasises that parents should not feel guilty about any role emotional control might play in stuttering. "There is no evidence that parents cause their children to stutter," Conture says.
+
+Only 30% of people surveyed felt comfortable with GM plants for food and only 18% felt comfortable with GM animals for food
+Australians are becoming more comfortable with new technologies like stem cell research but still have strong reservations about genetically modified foods, a new survey shows.
+The survey, conducted by the Australian Centre for Emerging Technologies and Society at Swinburne University in Melbourne, asked more than 1000 people about their views on emerging technologies.
+"Overall, Australians are optimistic about science and technology," says Professor Michael Gilding, director of the centre that conducted the survey, the Swinburne National Technology and Science Monitor.
+The poll has been conducted each year since 2003 and the latest results were gathered in 2005. 
+"The interesting thing about the last three years is that people seem to be becoming more comfortable with the technologies that we've been monitoring," Gilding says.
+On the subject of stem cell research, Australians seem to be more comfortable compared to 2004, the survey shows. 
+Research conducted in public institutes garnered a higher approval rating, and men tended to be more comfortable than women with the research.
+But when the respondents were asked about genetically modified crops or animals, their reaction was decidedly more negative.
+"That was the stand-out from our point of view," Gilding says. "Overall, people are still very uncomfortable with those technologies."
+Only 30% said they were comfortable with GM plants for food, the researchers found.
+When respondents were asked to rate their comfort level with GM crops, they gave an average score of 3.9 on a scale where zero was 'not at all comfortable' and 10 represented 'very comfortable'.
+The survey also found that just 18% of people were comfortable with genetically modifying animals for food, giving an average score of 3.1 out of a possible 10.
+In the end, people are probably weighing the perceived risks of GM foods against their benefits, Gilding suggests. "I suppose the bottom line is that they don't see any benefit for themselves."
+Craig Cormick, manager of public awareness for the government's Biotechnology Australia, says that broad questions about attitudes to GM food can miss subtleties in the way people think about the issue.
+For example, individuals will view the risks and benefits of GM foods differently depending on the food, he says. "Attitudes to GM wheat will be different to doughnuts with GM soy in them."
+In other findings, the survey showed that 80% of people agreed that science and technology are continuously improving our quality of life. This figure has been consistently high since the first survey in 2003.
+Respondents also said they most strongly trusted science information they get from the CSIRO, universities, hospitals and scientists. In general, they did not trust the media.
+
+The 'fertilising effect' of rising CO2 on crops like wheat could be only half as much as previously thought
+Increases in atmospheric carbon dioxide may be less of a boon to crop agriculture than previously thought, according to a new study 
+Plant biologist Dr Andrew Leakey of the University of Illinois at Urban-Champaign and colleagues report their findings in today's issue of the journal Science.
+To date, IPCC scientists and others have said increased photosynthesis due to higher carbon dioxide levels could offset crop losses brought about by higher temperatures and lower soil moisture in a warmer global climate. 
+But Leakey and colleagues predict the 'fertilising effect' of rising CO2 will be only half as much as has been thought by 2050.
+"What we're saying is the fertilisation effect of CO2 will not be as good a thing as was previously thought," says Leakey. "The current predictions are over-optimistic."
+The researchers say the IPCC's data come from old experiments on crops grown in greenhouses and shelters that don't properly capture real field conditions.
+Studies using special field experiments show the actual benefit from rising CO2 to world staples, such as corn, rice, sorghum, soybeans and wheat, they say.
+The field experiments involve Free-Air Concentration Enrichment technology experiments, in which crops are grown in a standard field, but are surrounded by special contraptions that allow CO2 to be released across them to simulate increasing atmospheric concentrations.
+"It's very much more real world," says Leakey.
+He says unlike in glasshouse experiments, the plants receive natural light, wind, temperature, rainfall and have as much root volume as they need.
+The field experiments also allow for pests and diseases that are part of real world conditions.
+"When you do these experiments in the field under realistic simulations of future conditions we see about 50% of the response [to increasing CO2] that was previously seen," says Leakey.
+Leakey says the results are averaged from a number of field experiments involving different crops in the US, Switzerland, New Zealand and Japan.
+He says good data is not available for the tropics and more research on this and on other areas, such as wheat production in Australia is needed.
+There also needs to be more field experiments to study the impact of changing ozone, temperature and drought on agriculture, says Leakey.
+He also says it may be possible to breed crops that are better able to make use of increasing CO2 levels.
+
+An unusual Antarctic sea spider with five pairs of legs. Its large proboscis is protruding towards the bottom of the picture
+Weird spider-like creatures that live at the bottom of the ocean and use a 'straw' to suck on their prey are baffling scientists.
+These sea spiders, some of which are blind, are defying scientific classification. 
+Marine zoologist Dr Claudia Arango of the Australian Museum in Sydney agrees they are arthropods, but which type? 
+She presented her research on these unusual and poorly understood animals recently at the Scientific Committee on Antarctic Research meeting in Hobart.
+"They are very weird looking animals," says Arango.
+For over 100 years, scientists have been puzzling over how exactly to classify sea spiders or pycnogonids.
+They crawl along the bottom of the sea floor, sometimes more than 6000 to 7000 metres down, where they live in the dark, feeding on slow-moving soft-bodied sponges and sea slugs.
+The creatures are segmented and have an exoskeleton, which makes them an arthropod, the same grouping as crustaceans, insects, centipedes and spiders.
+But they also have a very strange collection of features, including a unique feeding structure.
+"They have a proboscis that's like a straw that they insert into the animals and suck out the juices," says Arango.
+Such features make it difficult to fit them into any of the known groups of arthropods.
+"They look like spiders, but they are not real spiders," says Arango. "It's been very hard to place them in a position within the tree of life."
+Arango has been studying the diversity and evolution of sea spiders.
+She has been using DNA and morphology to construct a family tree, using 60 species of sea spiders from all over the world.
+
+Discovery poised for launch
+Bad weather has forced the US space agency to postpone the launch of the space shuttle Discovery.
+The next launch is set for 04:38 Wednesday Australian Eastern Standard Time (18:38 Tuesday UTC). 
+The decision by NASA to cancel lift-off came minutes after the seven crew members boarded the spaceship, even before the vessel's hatch was closed.
+Hours before, NASA forecasters estimated there was only a 30&nbsp;% chance that weather conditions would favour a launch, as thunderclouds menaced the Kennedy Space Center. 
+"We've concluded that we're not going to have a chance to launch today," launch director Mike Leinbach told the crew as they sat strapped into their shuttle seats. 
+"OK, we copy," said shuttle commander Steve Lindsey. "Looking out the window, it doesn't look good today, and we think that's a great plan."
+Too many risks
+The mission management team's chairman John Shannon confirmed bad weather had prevented the launch.
+"We had the vehicle ready to go, the crew ready to go and it's just that one thing that we really don't control, the weather, that kept us from launching," he told reporters.
+Any rain during lift-off might damage the spaceship's heat-shielding tiles, and a lightning strike could knock out the computers that control the ship. 
+Even thick, high clouds can make a launch hazardous.
+Discovery's mission is only the second since the 2003 Columbia accident, and another disaster or serious problem could end the shuttle program.
+NASA is hoping to fly 16 more missions to complete the A$134.5 billion (US$100 billion) space station before the shuttle fleet is retired in 2010. 
+Debates over safety
+Shuttle safety has been at the forefront of the program since Columbia disintegrated on re-entry in 2003, killing seven astronauts.
+NASA has twice redesigned the shuttle's fuel tank, which shed insulating foam that triggered the accident. 
+The agency's top engineer and chief of safety wanted more repairs on the tank before Discovery was launched, but NASA administrator Michael Griffin overruled them, arguing that if foam falls again from the fuel tank and damages the shuttle, the crew could stay aboard the space station and await rescue.
+Griffin says the debate over safety is a good thing. 
+"NASA had been criticised in the past for adhering to groupthink, for enforcing a needless conformity in decision-making," he said on CNN's Late Edition."
+"We have difficult, technically complex and subtle decisions to make ... We did the best analysis we can, and we make a decision, and I'm comfortable with that." 
+Delaying the launch would put more pressure on the shuttles, which are the only vehicles that can deliver and install the station's remaining trusses, solar arrays and laboratories. 
+The agency plans two more flights this year and about four a year until the station is finished and the fleet is retired. 
+NASA had hoped to resume space station construction last year, but the shuttle's fuel tank failed its first test flight.
+Engineers then removed two long wind deflectors from the tank, which had shed foam during Discovery's 2005 lift-off.
+
+We have the technology to clone animals and even humans, but what have we gained ten years after the first sheep was cloned from an adult cell?
+This Wednesday marks ten years since a lamb named Dolly, born in Scotland, made international headlines as the globe's first cloned mammal.
+She also triggered a storm of dreams, dread and ethical polemic that hasn't abated since.
+A river of money and hope, directed into the quest for cures for cancer, heart degeneration, Alzheimer's and other crippling disease, has also flowed from the event. 
+But there has been anguished debate, bitter opposition and the crafting of laws and guidelines to restrict or shape cloning research.
+In Australia, a legislative review by former federal court judge John Lockhart last year recommended lawmakers lift the current ban on therapeutic cloning.
+However, a number of government ministers oppose the recommendation and Prime Minister John Howard has promised a party room debate in August before a decision is made.
+Questions have also been raised about what, exactly, scientists have achieved with the creation of Dolly.
+"Where has Dolly taken us?" asks Sue Mayer, a doctor who is a member of GeneWatch UK, a British watchdog that monitors biotechnology. 
+"The biggest worry is that she has taken us down a blind alley.
+"Rather than tackling the root causes of disease, we are going for hype and quick fixes which may never deliver. 
+"And she's opened this prospect of reproductive cloning, a door which scientists try to keep open but which we should firmly close."
+Somatic cell nuclear transfer
+The technique that led to Dolly is called somatic cell nuclear transfer and has remained essentially unchanged over the decade. 
+A mammalian egg is taken, and its nucleus, the DNA program for making life,  is removed.
+ The nucleus is replaced through a microscopic glass tube by the nucleus of a cell from the animal to be cloned. 
+The reconstructed egg is then treated with a jolt of electricity and placed in a dish of nurturing chemicals to make it divide.
+A few days later it becomes a cluster of cells big enough to be transplanted into the surrogate mother's uterus. 
+Dolly, created at the Roslin Institute in Edinburgh, was named after Dolly Parton, the big-busted country and western singer, because the cell that was cloned came from a sheep's mammary gland. 
+Her lab name, rather less media-friendly, was 6LL3.
+ It later emerged that the same team, managed by Ian Wilmut, had previously created two sheep clones from embryonic cells.
+So, strictly speaking, Dolly was the first mammal to be successfully cloned from an adult cell.
+Not all good news
+After this breakthrough, other cloned species swiftly followed: horses, bulls, pigs, mice, rats, rabbits, cats and dogs and others. 
+But the miscarriage rate of transplanted eggs is extremely high, and of those embryos that make it to term, many have deformities or, as happened with Dolly, die prematurely, a clear warning to any scientist mad or foolish enough to try to make a cloned baby. 
+ The suspected cause is that the genetic software isn't transferred entirely, or is somehow damaged in the transfer. 
+As a result, the machinery malfunctions - genes don't switch on or off as they should in the complex ballet of making proteins.
+So if cloning is frustrating, costly and potentially risky, why bother with it? 
+The most alluring reason is medical. 
+A cloned lab animal such as a mouse can provide a very useful standardised tool for experiment. 
+And a farm animal that can be engineered and cloned to produce rare pharmaceutical proteins in its milk, Dolly was created with this in mind, could help save lives and ease suffering.
+Embryonic stem cells and ethical firestorms
+But the most glittering prize of all is to harness cloning to embryonic stem cells, the primitive master cells of early-stage embryos that famously have the power to develop into almost any tissue of the body.
+Researchers believe embryonic stem cells can some day be coaxed into regenerative tissue that could repair brain cells, nerves, kidneys, livers and other organs damaged by disease.
+So if these stemcells are copies of the patient's own DNA, they would not be rejected by the immune system.
+But here comes the ethical firestorm. 
+Some religious groups already oppose the use of human embryonic cells, saying that this tissue has the same value as a life.
+Yet there is an added queasiness about human cloning that is shared by many others, even if the immediate goal is therapeutic and nothing is created beyond a tiny cluster of cells, a further step will have been taken towards baby cloning. 
+At the moment, patient-specific embryonic stem cells remain beyond the horizon.
+The only scientist to have claimed to have made them, South Korea's Hwang Woo-Suk, was unmasked in January as a fraud.
+As for reproductive cloning, many countries introduced laws after a renegade sect, the Raelians, claimed in late 2002 to have produced the world's first cloned baby. 
+That claim has never been independently confirmed or even examined, and most scientists scoff at it.
+That said, many also predict that the first cloned human is only a matter of time. 
+"The (reproductive cloning) laws that are in place are pretty well-established throughout the world, but there are also laws in place against murder and suicide," says James Bradley, a professor of cell and developmental biology at Auburn University in Alabama.
+
+Plants like corn could be a green source of plastics using a new technology to turn starch into other products
+Scientists have come up with a way to produce a chemical from fruit sugar that they say is remarkably similar to one that comes from petroleum.
+The method, reported by Professor James Dumesic of the University Wisconsin, Madison, could put plants such as corn on par with petroleum, reducing our dependency on petroleum products and creating more environmentally friendly ones.
+"The nice thing about using biomass as a replacement for all these petroleum products is that it is greenhouse neutral," saysYuriy Roman-Leshkov, who with Dumesic and colleagues reported their findings in the current issue of Science.
+When a plant-based product eventually decomposes or is burned, as in the case with fuel, it doesn't introduce additional carbon dioxide into the atmosphere, the way petroleum products do, he says.
+Nice idea, but how's it done?
+It's a great idea, but finding an efficient, cost-effective way to turn the starch into other products is difficult.
+Molecules that come from petroleum are easy to work with and can be strung together in different combinations to produce everything from the polyester of a leisure suit to the polypropylene of a fleece jacket to the polyethylene terephthalate of a two litre bottle of soft drink.
+Petroleum molecules are also cost efficient. Almost all the petrochemical that goes into making a product ends up in the product, so there is very little waste.
+Not so easy with biological molecules
+But doing the same thing with biological molecules is not so easy.
+"Biological molecules tend to be much more complex, so because of that, doing specific chemistry to make a specific molecule is more challenging," says Brent Shanks, associate professor of chemical and biological engineering at Iowa State University.
+"You are going to have to develop new processing paradigms," says Shanks, who isn't a member of the research team.
+Dumesic and his colleagues think they have developed a new paradigm.
+First, they dissolve sugar and water and then add a catalyst to the mix. Next, they mix in an organic solvent and heat it to 180&deg;C.
+The process causes the sugar to lose three water molecules, which blend in with the rest of the water. The leftover substance becomes the chemical hydroxymethylfurfural, or HMF.
+HMF looks and behaves a lot like a petroleum-based molecule and could be strung together in different combinations to produce plastics and fuels.
+The challenge, says Shanks, will be to get industry to adopt HMF. Although it functions similarly to petroleum-based chemicals, it's still slightly different.
+"Can the industry reconfigure to handle those slightly different properties?" he asked. "At the end of the day, it's all about cost."
+
+Scientists may have underestimated how long it takes for CFCs to reach Antarctica's stratosphere and how long they stay there
+Despite widespread international reductions in ozone destroying chemicals, the Antarctic ozone hole will probably continue its annual appearance for another 60 years, say atmospheric scientists, 20 years longer than previous estimates.
+A new model that analyses the effects of ozone gobbling chlorofluorocarbon (CFC) emissions predicts a return to pre-1980 stratospheric ozone levels over the southern continent in 2068.
+What's more, no meaningful shrinking of the ozone hole should be expected before 2024, say US researchers from NASA, National Oceanic and Atmospheric Administration (NOAA) and the National Center for Atmospheric Research in a recent issue of Geophysical Research Letters.
+"The [previous] models underestimated the amount of chlorine and bromine over Antarctica," says NASA atmospheric scientist Dr Paul Newman, referring to the two elements that tear ozone apart. "That's why we underestimated the recovery rate."
+One reason for earlier miscalculation is that CFC quantities over Antarctica were originally measured indirectly, by how much ozone destruction they caused. 
+But when far more chlorine and bromine is present than needed to destroy all the ozone over Antarctica, it's difficult to predict the consequence of such a surplus.
+Saturated with chlorine
+In the 1990s the stratosphere over Antarctica saw the first of this sort of "saturation effect", says Newman, with 100% ozone destruction and plenty of chlorine and bromine to spare.
+There can be no significant change in ozone destruction until the levels of harmful chemicals at least drop below the saturation level. The new model estimates that will happen by 2018, with a detectable reduction in ozone destruction by 2024.
+"Now we understand how the models were wrong," Newman says.
+Another change to the model comes from new information on how long it takes chlorine-containing CFCs to reach the Antarctic stratosphere and how long they linger, says atmospheric researcher Dr John Austin of NOAA's Geophysical Fluid Dynamics Laboratory and the UK's Met Office.
+"Over the last few years we've realised that it takes a lot longer for the chlorofluorocarbons to be taken out of the atmosphere," says Austin. The longer they linger, the slower the ozone recovers.
+Yet another concern that has been raised in recent months is that the amounts of CFCs still being emitted hasn't dropped off as quickly as expected. That could possibly add more delays to ozone recovery at both poles.
+"In principle you could have another delay of another couple of decades," says Austin. "You keep adding more and more delays and you're starting to look at another 30 years. That's a problem."
+
+These dodo bones, found recently on the island of Mauritius, tell a different story of how these birds became extinct
+Scientists who unearthed a mass dodo grave in Mauritius say they have found evidence showing a natural disaster killed the birds long before humans arrived on the Indian Ocean island.
+Most theories about how the dodo became extinct blame early settlers who found the plump flightless bird in the 16th century and hunted it relentlessly. 
+Now, researchers say there may have been additional reasons for the dodo's demise.
+"There are indications that the fossil-rich layer represents the result of natural disaster wiping out a significant part of the dodo-ecotope," the researchers say.
+While the latest find does not disprove the human theory, the scientists are convinced there was a mass dodo death, possibly caused by a cyclone or flood, pre-dating the arrival of humans, says Christian Foo Kune, of the sugar estate where the remains were found.
+"The fact that there are such a wide range of animals there, small and big ones, suggests that there was a sudden natural disaster," he says. 
+"The mass grave also shows no domestic animals, so it is prior to the arrival of man." 
+The bones were thought to be at least 500 years old, he adds.
+"We could be talking about a cyclone or repeated cyclones, flooding or a sudden rise in [sea] water levels that trapped the animals there," he says. 
+The scientists from the Dodo Research Programme last month recovered a wealth of dodo remains and fossils of other animals and plants, including now-extinct Mauritian giant tortoises, parrots and tree seeds, from a sugar estate in the southeast. 
+Researchers on the project say the fossils should enable them to reconstruct the dodo's world in the 10,000 years before humans found the bird and determine what caused it to die out. 
+Foo Kune says that as the deaths at his site occurred before the final extinction of the dodo more than two centuries later, the scientists believe it does not rule out the idea that bird became extinct by human causes. 
+Portuguese sailors first visited Mauritius in the 16th century, and Dutch settlers colonised it the following century, which is when the dodo died out.
+Unused to predators, the dodos were not frightened of the human settlers who hunted it and destroyed the forests that provided its habitat.
+Passing ships also brought rats, which ate the birds' eggs located in nests on the ground.
+
+Details of the world's first partial face transplant have been published online in The Lancet journal. But ethical issues remain
+The world's first partial face transplant, carried out by French doctors last November, has been acclaimed by the medical establishment as a historic achievement, although major risks remain unresolved. 
+Controversy had swirled around the pioneering operation carried out by a team led by Professor Bernard Devauchelle in Amiens, northern France, with critics suggesting it was fraught with surgical and psychological peril. 
+But, in a sign that the exploit has been accepted by the core of the medical community, Devauchelle provides a detailed account of the transplant procedure in the prestigious, peer-reviewed journal The Lancet. 
+He also says that the patient's state, at the four-month mark, was fine.
+"The technical feasibility of the procedure has been clearly demonstrated, with no surgical complication," says Devauchelle, whose paper is published online. 
+"The functional result will be assessed in the future, but this graft can already be deemed successful with respect to appearance, sensitivity, and acceptance by the patient."
+The patient, Isabelle Dinoire, 38, lost her nose, lips and right cheek after she was savaged by a dog.
+On 27 November, a triangular-shaped part of the face of a 46-year-old woman, who was declared brain dead after suffering a severe stroke, was grafted on to Dinoire's face.
+Thinking of rejection
+Microsurgery was used to suture arteries, veins and motor nerves, and Dinoire was given immunosuppressant drugs aimed at thwarting rejecting of the transplanted organ.
+She was also given two grafts of bone marrow, four days and 11 days after the transplant, to help produce white blood cells to fight off infection, a frequent consequence of taking immunosuppressors.
+Bone-marrow transplants are themselves risky, sometimes causing life-threatening complications. 
+One of the surgeons who took part was Professor Jean-Michel Dubernard, who carried out the world's hand-forearm transplant.
+Two analyses of the operation, also published online by The Lancet, pay tribute to Devauchelle's work.
+But they also raise questions over the longer term. 
+German facial surgeon Dr Patrick Warnke of the University of Kiel hailed the operation as "a new milestone". 
+But he warned, "failure of the [immunosuppressant] regimen chosen could prove devastating, with the possible loss of the transplanted face at any time". 
+In addition, heavy use of these drugs also boosts the risk of cancer, meaning that a woman who before the operation was otherwise healthy despite her major handicap "is now at great risk", he says.
+The ethics of transplants
+Dr Edgardo Carosella of the St Louis Hospital in Paris and Thomas Pradeu of Sorbonne University says the ethical dilemma of a face transplant remain unresolved.
+In the case of the first hand transplant, the recipient, New Zealander Clint Hallam began to view the organ as alien, stopped taking immunosuppressant drugs and eventually begged, successfully, for the hand to be amputated.
+"Every graft of a visible organ leads to an identity split, the consequences of which can be very serious if the recipient does not succeed in psychologically accepting the organ and in rebuilding its social expression in everyday life," say Carosella and Pradeu.
+These and other issues are being mulled by UK medical watchdogs as they vet an application by London surgeons to carry out the world's first full-face transplant.
+
+Professor Hwang Woo-suk arrives for trial to face charges of fraud and embezzlement
+Disgraced stem-cell scientist Professor Hwang Woo-suk has admitted to fabricating some data that went into a landmark paper but says he was duped by junior researchers into believing the bulk of his team's findings were valid. 
+Hwang, once celebrated as a national hero, was indicted in May after prosecutors said he was the mastermind of an elaborate scheme to make it look like his team had produced stem cell lines through cloning human embryos. 
+"I admit to the suspicion of fabrication," he said in court as prosecutors questioned whether he personally altered parts of data for a 2005 paper to make it appear as if the team had made more stem cell lines then they had actually produced.
+"It was clearly my wrongdoing, I admit it." 
+Hwang has apologised previously for the discredited papers but this week offered the most detailed account of his role in data manipulations that led to the team's downfall. 
+He admitted to altering a data sheet given to him by a team member to make it look like a stem cell line had been created in one experiment before the data was given to a US researcher helping to write the paper. 
+Hwang also said he knew his team did not produce as many stem lines as they had claimed. 
+He said he accepted responsibility for a discredited study on developing patient-specific embryonic stem cells that was published in the US journal  Science.
+A separate investigation panel that debunked Hwang's papers questioned whether the team had produced any stem cell lines.
+Others implicated 
+He said he was unaware of much larger fabrications in data provided by some junior researchers. 
+"I believed the test results brought to me by researchers that supported the findings in the papers," Hwang said. "Not all the responsibility for the fabrications lies with me."
+Hwang also denied he broke a bioethics law but said his team did pay for human eggs that had been donated for his study. 
+Prosecutors have charged Hwang with misusing and embezzling the equivalent of US$2.96 million (A$3.98) in state funds and private donations as well as fraud and violating bioethics laws in procuring human eggs for his research. 
+Misuse of state funds carries a penalty of up to 10 years' jail, while violating the bioethics law can lead to three years' imprisonment, prosecutors say.
+Emotional testimony
+Hwang spoke with mounting emotion as he answered questions about the integrity of the science in his team's work. 
+"We still want to believe the veracity of the stem cell lines, which we hope will be verified by a world-renowned lab, not some incompetent committee from Seoul National University," Hwang said. 
+An investigation panel at Seoul National University, where Hwang once worked, said in a report in January that Hwang's team deliberately falsified key data in two papers on embryonic stem cells that have since been retracted by Science. 
+In a 2004 paper, Hwang's team said it had developed stem cells from a cloned human embryo and in a 2005 paper said it had produced tailored embryonic stem cells. 
+The reported breakthroughs had raised hopes because they seemed to hasten the day when genetically specific tissue could be grown from embryonic stem cells to repair damaged organs or treat diseases such as Alzheimer's.
+
+Vascular disease may be associated with particular types of migraine
+Adults who suffer from bouts of migraine without aura have slightly narrower retinal blood vessels than adults without migraine, Australian research shows.
+The finding supports the hypothesis that microvascular disease may be associated with certain types of migraine, investigators note.
+They publish their report in the journal Headache, a journal of the American Headache Society.
+Dr Gerald Liew from the University of Sydney and colleagues took photographs of people's retinas as part of the Blue Mountains Eye Study.
+The researchers measured the diameters of blood vessels in 2335 people over the age of 54 who took part in the population-based cohort study.
+People with a history of migraine without aura had narrower retinal blood vessels, or arterioles, than those with a history of migraine with aura or people with no history of migraine. 
+The findings held up in analyses adjusting for potentially confounding factors, the researchers say.
+
+Gooooal!
+A German scientist has used nanotechnology to create what he believes is the world's smallest soccer pitch.
+Dr Stefan Trellenkamp, from the University of Kaiserslautern, made the pitch by using an electron beam to engrave lines onto a tiny piece of acrylic glass.
+The pitch measures 380 by 500 nanometres and can only be seen through an electron microscope.
+"I am really, really proud," the nanotechnology researcher says.
+"The only problem is that I really don't know what to do with it. I can't put it on show as no one can see it," he says. "I guess it'll just stay in my drawer for the time being." 
+Trellenkamp says it took him a whole day to etch the pitch, which is so small that 20,000 of them could fit onto the tip of a human hair.
+
+A koala retrovirus is integrated into the koala genome and its genetic material is passed from parent to offspring
+A cancer-causing virus is gradually invading the genome of Australia's koalas, researchers say.
+Rachael Tarlinton, a PhD student from the University of Queensland, and colleagues made the unexpected discovery while studying koala retrovirus (KoRV), which causes leukaemia and immune deficiencies.
+Until now, scientists had thought KoRV was an endogenous virus, a virus that has become integrated into its host's genome and passed from parent to child like normal genes.
+But when Tarlinton and her colleagues examined the virus in koalas throughout Australia they found that some populations were infected with the virus and others were free of it.
+Their findings are published today in the journal Nature.
+The researchers also found that KoRV is highly active and variable between individual koalas, suggesting it is in transition between infectious and endogenous forms.
+"That was the real surprise," says co-author Associate Professor Paul Young. "That just totally changes what we think about endogenous retroviruses."
+Endogenous viruses are found throughout the animal kingdom, including in humans, but have normally been integrated into their host genomes for thousands of years.
+Island life
+When the researchers studied koalas on Kangaroo Island, off the south coast of Australia, they found that the marsupials were completely free of the virus.
+The population on that island was established around 1900 when koalas on the mainland were being killed by hunting.
+Together with other evolutionary evidence, this suggests that KoRV probably began invading the koala genome between 100 and 200 years ago, Young says.
+Early studies, he says, suggest the virus might have come from Asian rodents.
+"We've had incursions from Asian rodents into northern Australia repeatedly over thousands of years," he says. "We think that's probably the route."
+Causing cancer
+Because the virus has only recently begun integrating into the koala genome, it still often causes cancers, the researchers note.
+"The koala is having to live with the high levels of cancers ... and there's not a lot we can do about that in the wild," Young says.
+For the scientists, the new findings offer a rare glimpse into what happens when an animal is faced with a viral challenge like this.
+"Coming to grips with how the koala handles this initial viral onslaught may give us insights into the dynamic events that occurred millions of years ago when retroviruses first invaded the human genome," Young says.
+
+Who's that?
+Monkeys recognise each other by comparing faces to an average stored in their brains, not by memorising what every monkey looks like, scientists say.
+And that probably also goes for people, explaining how humans can recognise faces in a fraction of a second, according to a study published online in the journal Nature today. 
+The scientists found that a monkey's brain did not keep track of different parts of a face, storing and then accessing the information to recognise others. 
+Instead it keeps a statistical average of the faces it has seen and uses it as a basis for comparison. 
+"When it sees a new face it compares it to this average and then it remarks upon the differences ... and that is how the face is seen," says Dr David Leopold, of the US National Institute of Mental Health. 
+"It elucidates how it is possible that you can so quickly and effortlessly, in just a few hundred milliseconds, recognise faces."
+Leopold and his colleagues pinpointed the recognition system while studying neurones in an area of the brain called the inferotemporal cortex in two macaque monkeys.
+The monkeys had been trained to recognise computer-generated human faces. 
+The scientists monitored single neurones to understand how groups of the brain cells work together to recognise faces. 
+"What we found is that the neurones in this part of the monkey's brain respond in a way that is extremely sensitive to the small differences in information between faces of different identities," says Leopold.
+Average face
+The activity of the neurones was monitored as the monkeys were shown an average face of a person and as it was artificially morphed to the full identity. 
+"The main finding was a striking tendency for neurones to show tuning that appeared centred about the average face," Leopold says.
+In psychological tests, humans identify faces in much the same way as monkeys so the researchers believe this aspect of the visual recognition system is similar in both species. 
+The results suggest that monkeys, and possibly humans, are primed to recognise minute facial changes.
+Facial expression is an indicator of emotion and intent, which could be crucial for survival.
+
+The star shield approaches the line of sight to the parent star. At this stage, the bright starlight swamps the planet light in the telescope. But if the shield blocks most of the starlight, planets may be easier to find
+A huge daisy-shaped shield that would block out light from parent stars could be used to find Earth-like planets in other solar systems, a US astronomer says.
+He and his team have designed a plastic 'starshade' measuring 45 metres in diameter that would orbit with a trailing telescope.
+The shield would block out light from parent stars, which would normally swamp light reflected from their planets, to enable scientists to map planetary systems. 
+Finding other planets is very difficult because their parent stars are about 10 times brighter. 
+"We think this is a compelling concept, particularly because it can be built today with existing technology," says Professor Webster Cash of the University of Colorado, who outlines his proposal today in the journal Nature.
+"We will be able to study Earth-like planets tens of trillions of miles away and chemically analyse their atmospheres for signs of life," he adds.
+The shield, which is known as the New Worlds Observer, would be launched into an orbit about 1 trillion miles from Earth and then opened. 
+Three thrusters would be used to keep it steady while the telescope trailing thousands of kilometres behind follows light from distant planets as it hits the space shield. 
+"The New Worlds Observer is actively being studied in academia, industry and government," Cash says. 
+He adds that if Earth-like planets exist, the starshade could find them within the next decade.
+One day, a ring of telescopes might be placed on the Moon with a fleet of orbiting starshades, Cash says. This would allow scientists to photograph distant planets.
+
+DVDs coated with a light-sensitive protein may be able to store 50 terabytes (about 50,000 gigabytes) of data
+DVDs coated with a layer of protein could one day hold so much information that storing data on your computer hard drive will be obsolete, says a US-based researcher.
+He says that the protein layer, made from tiny genetically altered microbe proteins, could allow DVDs and other external devices to store terabytes of information.
+Professor V Renugopalakrishnan of the  Harvard Medical School in Boston reported his findings at the International Conference on Nanoscience and Nanotechnology in Brisbane this week.
+"What this will do eventually is eliminate the need for hard drive memory completely," he says.
+Renugopalakrishnan says high-capacity storage devices like the new protein-based DVDs will be essential to the defence, medical and entertainment industries.
+These trade in terabytes of information with the transfer of information such as satellite images, imaging scans and movies.
+"You have a compelling need that is not going to be met with the existing magnetic storage technology," he says.
+Renugopalakrishnan says the new protein-based DVD will have advantages over current optical storage devices (such as the Blue-ray).
+It will be able to store at least 20 times more than the Blue-ray and eventually even up to 50,000 gigabytes (about 50 terabytes) of information, he says.
+The star at the centre of the high-capacity DVD is a light-activated protein found in the membrane of a salt marsh microbe Halobacterium salinarum.  
+The protein, called bacteriorhodopsin (bR), captures and stores sunlight to convert it to chemical energy.
+When light shines on bR, it is converted to a series of intermediate molecules each with a unique shape and colour before returning to its 'ground state'.
+The intermediates generally only last for hours or days. 
+But Renugopalakrishnan and colleagues modified the DNA that produces bR protein to produce an intermediate that lasts for more than several years, which paves the way for a binary system to store data.
+"The ground state could be the zero and any of the intermediates could be the one," he says.
+The scientists also engineered the bR protein to make its intermediates more stable at the high temperatures generated by storing terabytes of data.
+The flip side
+Renugopalakrishnan says making large amounts of information so portable on high-capacity removable storage devices will make it easier for information to fall into the wrong hands.
+"Unfortunately science can be used and abused. Information can be stolen very quickly," he says. "One has to have some safeguards there."
+In conjunction with NEC in Japan, Renugopalakrishnan's team has produced a prototype device and estimate a USB disk will be commercialised in 12 months and a DVD in 18 to 24 months.
+The work has been funded by a range of US military, government, academic institutions and commercial companies, as well as the European Union.
+
+The telescope, a prototype of which is seen here, will use tiles to gather radio waves from the early universe
+An innovative radio telescope made up of square tiles instead of conventional dish antennas will be built in outback Western Australia to study what switched on the first stars.
+The Mileura Widefield Array, which will cover an area 1.5 kilometres in diameter, will use 500 six metre square 'tiles' to gather radio signals from its site in the mid-west of the state.
+The array will operate at low frequencies to 'see through' the neutral hydrogen, which is opaque to optical light, that filled the early universe.
+"Less than a billion years after the Big Bang something happened to ionise the neutral hydrogen so that the universe became transparent as it is today," says Dr Brian Boyle, director of CSIRO's Australia Telescope National Facility.
+"The question is what? Was it massive stars, quasars, black holes?  We don't know. But by looking at the primordial constituents of the gas and how it has been ionised we will be able to derive some important limits." 
+The array is being built by Australian and US partners as part of the preparation for the Square Kilometre Array (SKA), a huge international radio telescope scheduled for operation in 2020.
+"The SKA will require a number of different front-end antennas to cover a wide frequency range," says Boyle, and the Mileura array will cover the low-frequency range.
+Mileura, a uniquely radio-quiet area, is Australia's proposed base site for the SKA, which, if successful, will include antennas as far afield as New Zealand.
+The Mileura array will operate at similar wavelengths used for FM radio and television. So, if it was built near a big city, signals would swamp radio signals from space.
+Computer power
+Computing power lies at the heart of the array, which will use modern digital signal processing and clever electronics to turn thousands of small, cheap, fixed dipole antennas into one of the most powerful astronomical instruments in the world.
+The signals or data from each of the antennas can be combined in different ways, effectively allowing the telescope to 'point' in any direction although no moving parts are required.
+Until recently, combining and analysing signals collected from multiple antennas, known as interferometry, took time as the recorded data had to be processed centrally.
+With the Mileura array a supercomputer will process the data instantly, in real time.
+CSIRO has invested A$20 million overall and the US National Science Foundation has awarded Massachusetts Institute of Technology US$4.9 million for the construction of the Mileura array which will begin in 2008.
+Other Australian partners include a university consortium led by the University of Melbourne, which includes the Australian National University and Curtin University of Technology.
+
+The new combustor injects fuel and air separately into the chamber through devices that look like drinking straws
+The developers of a new combustion chamber that uses a simple and inexpensive design to burn fossil fuels say it emits almost no nitrogen oxide, a big contributor of smog and acid rain.
+The combustor, developed by Assistant Professor Ben Zinn and his team at the Georgia Institute of Technology, is not suitable for the ever-fluctuating environment of a car's engine. 
+But it could replace the steady-state combustion chambers of industry and power generation, which the US Environmental Protection Agency says spews more than half of all energy-related emissions into the atmosphere. 
+Until now, developing a low-emission combustor has proven challenging for a couple of big reasons.
+For fuel to burn, it must be mixed with air. Conventional combustors premix the air with the fuel and inject the mixture into the bottom of a tube-shaped chamber.
+Inside the chamber, the molecules are set aflame at temperatures over 1800&deg;K. At those temperatures, the air molecules break down and their two main elements, nitrogen and oxygen, begin to react and form nitrous oxide and carbon monoxide.
+Before the new molecules can be burned, they escape through the top of the tube as emissions. Premixed fuel can also cause flames to flash back, burning the fuel nozzle.
+Engineers have tried several strategies for reducing flashback and emissions, among them burning the fuel mixture at temperatures lower than 1800&deg;K. But the lower the temperature the weaker the flame and the more likely that it will experience 'blow out'.
+"It's like having a very weak candle flame. Every time there is a breeze, it blows out. It's not very robust," says Zinn. "In our system, we can go to the lower temps without losing the flame."
+The new device, called a stagnation point reverse flow combustor, is robust because of its fairly simple design, say its developers.
+Instead of being tube-shaped, it is designed more like a drinking glass - open on the top and sealed on the bottom.
+Over the top of the chamber is a special injector that looks like a skinny straw inserted into a fat straw.
+Fuel flows through the skinny straw down into the chamber; air flows into the chamber through the fat straw.
+The ingredients move down the centre of the chamber, mix, ignite and burn in a low-temperature flame.
+Once they reach the bottom of the chamber, the molecules move to the wall of the chamber and begin to rise in an attempt to escape.
+But on their way back up, they come into contact and ignite the mixture of fuel coming down.
+"Ben Zinn is one of our country's best combustion scientists," says Richard Dennis, turbine technology manager at the US Department of Energy's National Energy Technology Laboratory.
+"He seems to get around two big issues: the premixing issue of fuels and air and the [flashback] issue. And he seems to do this in a simple geometry."
+According to Zinn, when the combustion process occurs stably at temperatures below 1800&deg;K, only one nitrous oxide molecule in one million escapes to the environment.
+Before such technology could make it to market, though, it will have to be rigorously tested.
+"Ben needs to produce more data that validates the performance and does it at conditions that are relevant to the application," says Dennis.
+Zinn thinks that in about a year, he could have the device working on residential water heaters or industrial boilers. 
+It would take several more years, but the combustor could one day be incorporated into gas turbines for power generation and even into aeroplane engines, he says.
+
+Current tests for BSE need brain or other tissue samples. But new research suggests that BSE leaves its mark in the blood, paving the way for a blood test
+Tests in hamsters suggest it may be possible to develop a blood test for mad cow and related diseases in both humans and animals before they develop symptoms, researchers report. 
+The study, published in the journal Science, also suggests that the damaged brain cells may 'leak' the infectious prions that cause the diseases, offering a chance to detect the disease in blood. 
+Such a test would allow animals to be checked before they enter the food supply.
+It could also screen people, including blood or organ donors, for the rare but devastating Creutzfeldt-Jakob Disease or CJD, and its close cousin, vCJD, the researchers say. 
+Current tests require brain or other tissue samples. 
+Mad cow disease, formally known as bovine spongiform encephalopathy or BSE, is part of the family of prion diseases that also includes scrapie in sheep, chronic wasting disease in deer and elk, and CJD in people. 
+BSE emerged in Britain in the 1980s and swept through dairy herds. Some people who ate infected beef products developed a form of CJD called variant or vCJD and at least 191 cases have been identified, mostly in the UK. 
+People can have CJD before they know it and in a few suspected cases, blood and organ donors may have unwittingly infected others. 
+Silent phase
+Professor Claudio Soto of the University of Texas Medical Branch at Galveston and colleagues infected hamsters with prions, the misfolded nerve proteins believed to cause the diseases, and then tested blood at various times. 
+They invented a technique known as protein misfolding cyclic amplification to accelerate the process by which prions convert normal proteins to misshapen infectious forms. 
+"With this method, for the first time we have detected prions in what we call the silent phase of infection, which in humans can last up to 40 years," Soto says. 
+Soto and his university have formed a company, called Amprion, to commercially develop the test. 
+Timing is crucial
+The test may need to be used at precise times, the researchers say. It worked best in hamsters 40 days after infection. It did not detect prions 80 days after infection. 
+Then at 114 days, after the hamsters started showing symptoms, the blood test again revealed prions.
+"It has been reported that large quantities of [infectious prions] appear in the brain only a few weeks before the onset of clinical signs," the researchers write. 
+Heart disease
+A second study in Science shows that mice infected with prions develop heart disease similar to a type known as amyloid heart disease in people.
+Dr Bruce Chesebro of the National Institutes of Health and colleagues say these diseases are marked by waxy protein deposits that stiffen the heart, limit its pumping ability and typically lead to fatal heart stoppage. 
+"Although several types of protein are known to form heart amyloid, this is the first time prion protein amyloid has been found in heart muscle and also found to cause heart malfunction," Chesebro says.
+
+The plan is to use magnets to attract iron oxide nanoparticles attached to genes
+Magnets may one day drag genes around the body in a novel form of gene therapy, says a Swiss scientist.
+The magnets would be attracted to iron oxide nanoparticles attached to the genes, a concept that has been tested in sheep.
+But many safety tests would be needed before this technology could be used in humans, says Professor Heinrich Hofmann of the
+Ecole Polytechnique Fédérale de Lausanne in Switzerland.
+Hofmann reported his findings at the International Conference on Nanoscience and Nanotechnology in Brisbane last week.
+Gene therapy has been beset with problems including the lack of a safe and effective vector to transport therapeutic genes into cells.
+Hofmann says his iron oxide nanoparticles are safer than commonly used viral vectors, which can mutate and influence the DNA of cells.
+"The iron oxide particle is less dangerous than a virus," he says.
+He also says the nanoparticles can be controlled more precisely than a virus because they can be moved into place with a magnet.
+In a recent experiment, Hofmann injected iron nanoparticles attached to a green fluorescent protein gene into the joint of sheep and used a magnet to move the gene into place.
+The sheep cells produced green fluorescent protein that glowed green under light, proving the success of the experiment, Hoffman says.
+The research has been published in the Journal of Magnetism and Magnetic Materials.
+Activating stem cells
+In another application, Hofmann is using magnets and iron oxide nanoparticles to activate the growth of bone stem cells.
+In vitro experiments have shown that iron oxide nanoparticles injected into stem cells can be vibrated with magnets to boost cell growth.
+"We know from a fracture that if you mechanically stimulate the bone then the growth is enhanced," he says. "The healing rate is improved. And we are now doing this on a cellular level."
+This work is being patented and is yet to be published.
+Safety issues
+Iron oxide nanoparticles are approved by the US Food and Drug Administration for use in magnetic resonance imaging, says Hoffman. 
+But these particles have different coatings not designed to penetrate cells, and are cleared via the blood into the liver.
+The iron oxide nanoparticles Hofmann uses have a coating of polymers and specific chemical groups designed to help them penetrate cells. 
+Because of this, and because the safety of nanoparticles in general is still being investigated, Hofmann says his laboratory is careful to contain the nanoparticles to prevent them from escaping.
+He says after doing their job, the nanoparticles would be cleared through the lymphatic system into the kidney where they would gradually be cleared from the body.
+But, he says, there is a risk the nanoparticles could create local inflammation or toxic shock.
+Another danger is they could clump together and clog up the kidney, says Hoffman, and many more safety tests are required.
+Hofmann's research is publicly funded.
+
+Differences in levels of gene expression between men and women may help to explain why they respond differently to drugs and diseases
+Thousands of genes behave differently in the same organs of males and females, researchers report, a finding that may help explain why men and women have different responses to drugs and diseases. 
+Their study of brain, liver, fat and muscle tissue from mice show that gene expression, the level of activity of a gene, varies greatly according to sex. 
+The same is almost certainly true of humans, the team at the University of California Los Angeles report. 
+"This research holds important implications for understanding disorders such as diabetes, heart disease and obesity, and identifies targets for the development of gender-specific therapies," says Jake Lusis, a professor of human genetics who worked on the study.
+Writing in the August issue of the journal Genome Research, the researchers say that even in the same organ, scores of genes vary in expression levels between the sexes.
+The smallest differences are in brain tissue.
+"We saw striking and measurable differences in more than half of the genes' expression patterns between males and females," says Dr Thomas Drake, a professor of pathology.
+"We didn't expect that. No one has previously demonstrated this genetic gender gap at such high levels." 
+Xia Yang, a postdoctoral fellow in cardiology who led the study, says the implications are important.
+"Males and females share the same genetic code, but our findings imply that gender regulates how quickly the body can convert DNA to proteins," Yang says. "This suggests that gender influences how disease develops." 
+In liver tissue, the findings imply male and female livers function the same, but at different rates. 
+"Our findings in the liver may explain why men and women respond differently to the same drug," Lusis says. 
+"Studies show that aspirin is more effective at preventing heart attack in men than women. One gender may metabolise the drug faster, leaving too little of the medication in the system to produce an effect." 
+Yang adds: "Many of the genes we identified relate to processes that influence common diseases. This is crucial, because once we understand the gender gap in these disease mechanisms, we can create new strategies for designing and testing new sex-specific drugs.
+
+The active ingredient in magic mushrooms produces spiritual experiences identical to those reported through history
+The active ingredient in hallucinogenic mushrooms produces a spiritual experience that can have lasting positive effects, a trial has shown.
+The ingredient, psilocybin, increases wellbeing and satisfaction with life two months after being taken, according to the research by scientists at Johns Hopkins Medical Institutions, which is published online today in the journal Psychopharmacology.
+Psilocybin is a plant alkaloid that affects the brain's serotonin system, in particular, the 5-HT2A receptor.
+"Under very defined conditions, with careful preparation, you can safely and fairly reliably occasion what's called a primary mystical experience that may lead to positive changes in a person," study leader Professor Roland Griffiths says.
+Australian professor of psychopharmacology at the University of Sydney, Ian McGregor, says he isn't surprised that the study confirms the ability of psilocybin to induce a spiritual state.
+"Psilocybin and related hallucinogens have been used since ancient times in religious rituals and this study is really formalising ... what many people already know," he says.
+But he says the apparent long-term benefit of the drug is "remarkable".
+"To see a positive effect two months later is quite striking," he says.
+However, the study also reports that about a third of the volunteers experienced fear and anxiety after taking the psilocybin and McGregor says it should be avoided by anyone with schizophrenia or other psychotic illnesses.
+First study of its kind in four decades
+In what is described as the first scientifically rigorous study of its kind in 40 years, 36 volunteers were given either psilocybin or a comparator drug methylphenidate hydrochloride.
+Subjects were asked to describe their experiences immediately after the session in a set of detailed psychological questionnaires and at a two-month follow up.
+More than 60% of subjects (22) described the effects of psilocybin in ways that met criteria for a full mystical experience according to established psychological scales, compared to only 4 of the 36 after the comparator drug.
+After two months, two-thirds rated the experience as either the singly most spiritually significant in their lives or rated it among their top five.
+The God spot?
+Professor John Bradshaw, an Australian neuropsychologist from Monash University, says the brain's medial temporal lobe is rich in serotonin receptors and has previously been described as the 'God spot' because it is active in transcendental states.
+In a commentary accompanying the article, Professsor David Nichols of the Purdue University school of pharmacy says it's likely that psilocybin triggers the same neurological process that produces religious experiences during fasting, meditation, sleep deprivation or near-death experiences.
+He says the current research adds to the emerging field known as neurotheology, or the neurology of religious experience, and could shed light on the "molecular alterations in the brain that underlie religious and mystical experiences".
+
+The threat of bad weather can leave some people crippled with fear, psychologists say
+If the prospect of bad weather causes you to obsessively monitor weather reports and makes your heart pound, head spin and palms sweat, you could be suffering from severe weather phobia, psychologists say.
+In the first survey ever on this disorder, US researchers have found that it's more than just "thunder phobia" or mild anxiety about tornadoes or hurricanes.
+They estimate one in five people could suffer from the condition.
+Severe weather phobics are truly panicked at the very thought of storms and can't function normally until the weather clears.
+"They get very afraid even when the possibility of severe weather is days away," says psychologist Professor John Westefeld of the University of Iowa.
+This is not the normal, healthy worry most people have and which motivates them to prepare for a storm.
+"They are really, really afraid."
+Westefeld and his colleagues published the results of a small study of severe weather phobia symptoms among 139 people in the current issue of the Bulletin of the American Meteorological Society.
+A quarter of the people surveyed about how they reacted to severe weather reported enough symptoms to be classified as moderately phobic.
+More than a storm in a teacup
+Symptoms include dizziness, shortness of breath, nausea, heart pounding, feelings of panic, sweating, feeling helpless, constantly monitoring TV weather reports, inability to sleep or eat and changing schedules days ahead at the possibility of bad weather.
+Fully 76&nbsp;% reported having multiple symptoms occasionally.
+"I really don't know how extensive it is," said Westefeld. "It's clear this is definitely out there."
+"There are probably several million people that have it," says Zeus Flores, the creator of the supportive website stormphobia.org and a self-described storm phobic.
+But, Flores adds, in most causes people are very good at hiding the problem, which doesn't help them deal with it.
+"Often family members may have a clue, but not friends and co-workers," Flores says.
+Severe weather phobics can feel an overwhelming dread during storm seasons and some move out of their home towns.
+"In my case I'd sleep in the closet at night with a map and a flashlight to track the storm," Flores says.
+Treating weather phobia
+Flores was part of an experimental storm phobia treatment program that Westefeld created in the 1990s. 
+The program is based on those that treat people with a fear of flying.
+An expert on the subject, in this case a meteorologist, is teamed with a counseling psychologist to provide sufferers with more factual information about what they fear and teach them techniques for relaxing.
+One factor that isn't helping storm phobics in the US is the way the media covers storms, says Flores.
+He says programs like the Weather Channel just used to provide weather reports.
+"Now it's MTV-esque and about getting higher ratings," he says.
+
+Carbon dioxide produced by burning fossil fuels has been blamed as a factor in climate change
+Hundreds of deaths caused by volcanic leaks of carbon dioxide around the world are worrying experts who are researching how to bury industrial emissions of the gas as part of an assault on global warming. 
+The concerns come as governments and companies investigate trapping  carbon dioxide, a greenhouse gas released by burning fossil fuels, and entombing it in porous rocks deep below the ground.
+But they have done little to explain the vast cost and possible risks of projects that advocates say could bury billions of tonnes of gas and do more to slow global warming than a shift to renewable energies like solar or wind power.
+"There may be massive public resistance, as we've seen with nuclear power" if governments fail to convince voters that storage is safe, says Dr Bert Metz, co-chair of a 2005 United Nations report on carbon sequestration.
+"Public acceptance...is a possible show-stopper if things are not done properly," he said during a recent conference of 1,000 researchers into carbon dioxide technologies in Trondheim, Norway.
+Carbon dioxide is a non-toxic gas produced from respiration by animals and plants, making up a tiny 0.04% of the air. 
+Levels are up 30% since the industrial revolution and most scientists say the rise is the main spur of global warming. 
+Deadly gas
+In pure form the gas can cause asphyxia because it is heavier than air and displaces oxygen. 
+In the worst case in recent decades, 1,700 people died after a catastrophic 1986 release of 1.2 million tonnes of carbon dioxide from the depths of Lake Nyos in Cameroon, according to the International Energy Agency.
+Thirty-seven people died from a similar seismic release from Lake Monoun in Cameroon in 1984.
+In 1979, an explosion at Dieng volcano in Indonesia released 200,000 tonnes of the gas, smothering 142 people on the plain below. 
+In April this year, three ski patrol workers died at Mammoth Mountain, California, when they were overcome by carbon dioxide while trying to fence off a dangerous volcanic vent.
+"Carbon storage is not risk-free but we think the risks are manageable," says Dr Philippe Lacour-Gayet, chief scientist for research and development at Schlumberger oil and gas services group, one of many companies involved in research. 
+He and other experts say any greenhouse gas stores would be in geologically stable regions far from earthquake zones and commercial carbon dioxide stores are safely in operation in Norway, Canada and Algeria.
+Proponents of carbon storage say the risks pale when compared with the threats of catastrophic climate change, which many scientists say will spur floods, droughts, heatwaves and could spread diseases and raise world sea levels. 
+Even so, massive storage could mean pipelines and stores under the countryside from Austria to Australia. 
+Convincing the public
+And the public may not take kindly to concentrating a normally harmless gas into a more risky form at a likely cost of tens of billions of dollars.
+A strong argument for public acceptance is that people accept a host of risks every day - flammable petrol in the fuel tanks of their vehicles, toxic natural gas piped into their homes or electricity generated from nuclear power. 
+"All sorts of toxic liquids and gases are already stored underground," says Professor David Reimer, a lecturer in technology policy at the University of Cambridge in England. 
+"Carbon dioxide poses a far lesser risk than many accepted hazards."
+Berlin has an underground store for explosive natural gas near the stadium where the World Cup soccer competition was played, he says.
+And acid gas is stored underground near Edmonton, Canada. 
+Carbon dioxide storage sites would have to be carefully chosen, and monitored for centuries.
+"I'm more worried about public acceptance of the costs than of the hazards of leaks," says Frederik Hauge, head of the Norwegian environmental group Bellona which favours carbon storage. 
+Metz's UN report said that storage could provide 15-55% of all the cuts in greenhouse gas emissions needed until 2100 - probably a bigger contribution than from renewable energies or from any revival of nuclear power.
+It estimates that the costs of generating electricity from a coal-fired power plant would typically rise to US$0.06-$0.10 per kilowatt hour with technology to capture and store carbon dioxide from US$0.04-US$0.05 on a power plant with no filters.
+Governments will also need to work out liability rules in the case of a leak. 
+Most experts suggest companies should initially be responsible but governments would take over, perhaps between five and 20 years after burial.
+
+Paternal age can have an impact on the health of newborn babies, research suggests
+The babies of older dads tend to be less robust immediately after birth than infants fathered by younger men, a new study shows.
+The research, published in the current issue of the journal Epidemiology, shows that new fathers in their 40s and 50s are slightly more likely to have an infant with a low Apgar score than fathers in their 20s. 
+The Apgar score, which was first created in 1952, rates the newborn on respiratory effort, heart rate, reflex irritability, muscle tone and skin colour with a value of 0 to 2 for each.
+The score is calculated at one and five minutes after birth and a score of 10 is the best result.
+In recent years, several reports have linked advanced paternal age with various adverse pregnancy outcomes, including foetal death and premature birth.
+But little was known about the impact, if any, on the physical condition of the infant at birth.
+What the records show
+To investigate, Dr Yuelian Sun, from the University of Aarhus in Denmark and colleagues analysed data from more than 70,000 couples who had a first infant born between 1980 and 1996. 
+The team reports that compared with fathers in their 20s, those between 45 and 49 years of age and those 50 years of age or older were 64% and 49% more likely, respectively, to have an infant with a one minute Apgar score between 1 and 3. 
+Fathers 45 years of age or older were at increased risk of having an infant with a five minute Apgar score of less than 7. 
+"The biologic link between advanced paternal age and low Apgar scores is unknown," Sun and colleagues say. 
+However, some studies have shown that "expression of specific paternal genes is crucial for the placental development and that chromosomal aberrations tend to increase with paternal age." 
+Reproductive medicine expert Professor Robert Jansen from the University of Sydney says fathers aged over 60 are also more likely to have children with serious genetic defects.
+"In really old men you start getting some rare conditions happening ... like dwarfism," he says.
+Professor Mark Bowman, a expert in male infertility and lecturer in obstetrics and gynaecology at Sydney University says the results could be a reflection of maternal problems.
+"You'd expect this would be a female effect," he says.
+"Older women are more likely to have babies with problems and older women have older husbands."
+
+Software that analyses how far your pupils dilate could be used to determine your age
+The 'red-eye' reducing software inside digital cameras could one day be used to verify a person's age, US researchers say.
+Andrew Gallagher, a senior research scientist at Eastman Kodak,  developed the technique, which has a range of applications.
+Among them are face recognition security systems, age-progression software to identify missing children, and devices that determine whether a person is old enough to buy alcohol or cigarettes.
+"We found that the features related to the red-eye artefact, the pupil dilation, are very good features to tell us how old someone is," says Gallagher, who recently filed a patent on the technology.
+That's because as people age, the muscles in their eyes naturally weaken, making it more difficult for the eyes to dilate effectively in response to changing light conditions.
+In fact, the dilation response goes down by a predictable number: about one millimetre for every decade a person is alive.
+Eyes close together
+But that's not the only predictable change in human eyes over time.
+A baby is born with adult-sized eyes. Though eyes don't grow, the distance between them does.
+Using this information, Gallagher built software that finds the red-eye artefact in an image and then, based on the distance between the eyes and how much the eye dilates, estimates the age of the subject.
+Currently the software can categorise a person into general age groups such as baby, child, teenager and adult.
+"It's very innovative; I've not seen it before," says Professor Tsuhan Chen, an expert in digital video and image processing at the Carnegie Mellon University in Pittsburgh.
+"By itself, it's one way of recognising the age. Combining it with other techniques would be the final way to approach this."
+In fact, Gallagher hopes to combine the red-eye feature with other face recognition techniques - such as determining the amount of hair, hair colour, and number of wrinkles - to better pinpoint age.
+"The idea would be to put as many features together as possible, and that would give you the most accurate reading," he says.
+Applications?
+Don't worry. No one will be showing up at your next birthday party with a device that calls you a liar. In fact, Kodak has not yet incorporated this technology into a product.
+According to Gallagher, it will mostly likely show up first as a way to organise and retrieve digital images.
+Imagine calling up all of the images of your first baby, for instance. An internet version of such a system could be supported by links to advertisers selling age-related products, its developers say.
+
+Banknotes and coins are home to fewer bacteria than we think
+The long-held belief that you can catch disease from handling money may be exaggerated, says an Australian researcher.
+A study by Dr Frank Vriesekoop, a lecturer in food science at the University of Ballarat, has found there are generally few pathogenic bacteria on banknotes and coins.
+"The potential [to spread disease] is still there. But I don't think it's all as bad as it's made out," he says.
+He will present the results of his study at the Australian Institute of Food Science and Technology annual conference in Adelaide today.
+He will also tell delegates that his team found low levels of antibiotic-resistant bacteria on banknotes and coins.
+Vriesekoop worked with New Zealand researchers from the Eastern Institute of Technology to look at the types and number of bacterial cells found on money on both sides of the Tasman.
+The researchers analysed coins and banknotes from mainly small food outlets such as cafes, small supermarkets and shops like butchers and bakers, all places where the person who handles food is also likely to handle money.
+Back in the laboratory, the researchers bombarded the coins with pulses of sound to dislodge any microbes on the surface. They then identified and counted the number of viable bacteria.
+The researchers found few bacteria, typically 1 or 2 cells per square centimetre.
+"Some batches appeared to be sterile," says Vriesekoop.
+He suspects that the copper and nickel in the 20 cent pieces and the aluminium and bronze in the dollar coins are toxic to many bacteria.
+The banknotes needed a different approach. They were placed in a device like a mini-washing machine that beats and swirls the notes in a special liquid. The scientists then analysed the liquid for microbes.
+This time, the counts were higher, typically 10 cells per square centimetre and varied much more between samples.
+Low levels
+The researchers found a range of organisms on coins and notes, including those that cause food poisoning or diarrhoea.
+These included low levels of coliforms such as Escherichia coli, bacteria typically associated with the colon and generally linked with poor hygiene; Staphylococcus aureus, a common organism with some strains that can cause disease in susceptible people; and Bacillus cereus, which causes food poisoning if cooking does not kill its tough spores.
+But what surprised the researchers was evidence of salmonella bacteria. 
+"It did worry me a bit," says Vriesekoop.
+Also surprising was the number of bacteria that were resistant to one or more commonly prescribed antibiotics, like amoxycillin, roxithromycin and cefaclor.
+"This was higher than I anticipated," he says.
+Potential to cause disease?
+While Vriesekoop says levels of bacteria were generally low, we still don't know how easily they are transferred from money to humans.
+"Do they grow or die? We don't know," says Vriesekoop, adding that this might be the subject of future research.
+He also hopes to work with the Royal Australian Mint to see how the raised surfaces of coins affect bacterial survival.
+Vriesekoop is also co-ordinating an international comparison of bacterial levels on currency from the US, UK and Ireland.
+The results, which he hopes to have at the end of the year, will help to confirm whether Australia's polymer notes are less hospitable to bacteria than paper notes used in most of the world.
+
+A chip implanted in the brain records cell activity and sends commands to a computer
+A paralysed man using a new brain sensor has been able to move a computer cursor, open email and control a robotic device simply by thinking about doing it, scientists say.
+They believe the BrainGate sensor, which involves implanting electrodes in the brain, could offer new hope to people paralysed by injuries or illnesses. 
+"This is the first step in an ongoing clinical trial of a device that is encouraging for its potential to help people with paralysis," says Dr Leigh Hochberg of Massachusetts General Hospital.
+The 25-year-old man who suffered paralysis of all four limbs three years earlier completed tasks such moving a cursor on a screen and controlling a robotic arm. 
+He is the first of four patients with spinal cord injuries, muscular dystrophy, stroke or motor neurone disease testing the brain-to-movement system developed by the company Cyberkinetics Neurotechnology Systems.
+"This is the dawn of major neurotechnology where the ability to take signals out of the brain has taken a big step forward. We have the ability to put signals into the brain but getting signals out is a real challenge. I think this represents a landmark event," says Professor John Donoghue of Brown University and the chief scientific officer of Cyberkinetics. 
+First, implant the chip
+The scientists implanted a tiny silicon chip with 100 electrodes into an area of the brain responsible for movement. The activity of the cells was recorded and sent to a computer that translated the commands and enabled the patient to move and control the external device. 
+"This part of the brain, the motor cortex, which usually sends its signals down the spinal cord and out to the limbs to control movement, can still be used by this participant to control an external device, even after years had gone by since his spinal cord injury," adds Hochberg, a co-author of the study published in the journal Nature.
+Although it is not the first time brain activity has been used to control a cursor, Professor Stephen Scott of Queen's University in Ontario, Canada says it advances the technology. 
+"This research suggests that implanted prosthetics are a viable approach for assisting severely impaired individuals to communicate and interact with the environment," he says in a commentary in the journal. 
+Faster, faster
+In a separate study, researchers from Stanford University describe a faster way to process signals from the brain to control a computer or prosthetic device. 
+"Our research is starting to show that, from a performance perspective, this type of prosthetic system is clinically viable," says Stephen Ryu, an assistant professor of neurosurgery at Stanford.
+
+Scientists are learning more about how baboons communicate and what this means for the evolution of human language
+A study of how baboons gesture with their hands suggests gesturing may have been a precursor to human language, scientists say.
+The findings could help to explain why humans often gesture with their hands, and particularly the right hand, when they speak.
+The right hand is controlled by the brain's left hemisphere, which is the source of most linguistic functions.
+Scientists believe communication by hand probably existed in apes 30 million years ago and was a forerunner to spoken and written language.
+French researchers Adrien Meguerditchian and Professor Jacques Vauclair studied a particular hand gesture in 60 captive baboons. 
+The gesture consists of quick and repetitive rubbing or slapping of the hand on the ground, and is used to threaten or intimidate others.
+The researchers, from the University of Provence, say this motion "might be comparable in humans to the slap of ... one hand toward the palm of the other hand".
+For the study, which is published in the journal Behavioural Brain Research, the researchers observed this gesture as it occurred naturally.
+They also triggered it by having a human abruptly shake his head and then glance at a baboon. Head shaking is another threatening move in the ape and monkey world, which includes all sorts of communicative gestures.
+"A nonhuman primate can effectively raise an arm to ask a social partner to groom it ... give another a little slap as an invitation to play, touch furtively the hand or genitals of another to greet it, slap the ground to threaten," the researchers say.
+Right hand, left hand
+Among the baboons in the test group that favoured a certain hand, 78% were right-handed and tended to gesture with this hand. Other studies have shown that most human babies and deaf individuals also communicate with their right hands.
+"There is little chance that our [primate] cousins will evolve language skills in the near future," the researchers say.
+"Monkeys and apes and their specific communication systems result from other evolutionary roads than those of humans ... It is very unlikely that the natural selection for primate species will reproduce exactly the same phylogenetic path that gave linguistic skills to humans."
+Like chimps
+William Hopkins, a US psychology professor at Berry College and an expert on the evolution of brain development in primates, says:
+"I agree with the findings and think this is a very good and interesting paper. In many ways the results are nearly identical to those we have previously found in chimpanzees."
+He explains that both chimps and baboons seem to use right-hand gestures for communication. This suggests the brain is asymmetrical when it comes to language, meaning that the left hemisphere tends to dominate.
+"It will be interesting to see whether the asymmetries in hand use seen in the baboon link at all to brain asymmetries as we have found in the chimpanzees," Hopkins adds.
+
+King penguins are keeping an eye on temperature and current flows in the Southern Ocean
+Penguins and seals are swimming around the Southern Ocean with sensors superglued to their heads in the name of science, a conference will hear this week.
+The animals are collecting data on water temperature and current flows, information that scientists will use to help complete global climate change models.
+The research, by a team of scientists from CSIRO, the Australian Antarctic Division and the University of Tasmania, will be reported tomorrow at the Scientific Committee on Antarctic Research meeting in Hobart.
+"We are using the penguins and seals as oceanographic observers," says team member Dr Steve Rintoul of CSIRO and Antarctic Climate and Ecosystems CRC.
+The team has recruited 15 king penguins and eight elephant seals from Macquarie Island, which is about 1300 kilometres north of the Antarctic continent.
+Sensors to measure temperature, pressure and location are superglued to the animals' heads along with a radio transmitter that sends data to a satellite throughout their journey through the Southern Ocean.
+As the animals dive down to catch fish, 200 metres deep in the case of penguins and 1500 metres for seals, the pressure sensors tell the scientists how deep the animals are and helps provide a profile of the sea's temperature.
+When they return to their home beach on Macquarie Island the animals moult and shed the equipment, which the researchers recover. 
+Making up for a northern bias
+Our current knowledge about ocean temperatures has mainly come from merchant ships in the northern hemisphere, says Rintoul.
+The Southern Ocean has a lot less shipping traffic and so there are relatively few measurements of ocean temperatures there.
+And this, says Rintoul, is the beauty of the penguin and seal oceanographers that swim to places that are hard for scientists to get to. 
+They can also deliver many more measurements.
+For example, a research vessel might deliver 150 temperature profiles in a six-week trip to Antarctica whereas the 15-strong penguin team delivers 36,000 profiles over their three-week journey.
+The seals dive deeper but less frequently and deliver 16,000 profiles in a six month season.
+One advantage of the seals is they are bigger than the penguins, which means they can carry more equipment. 
+Specifically, seals carry sensors that measure salinity, which is important for understanding the density of the ocean and calculating the specific speed of currents.
+Ocean currents the key
+Rintoul, a physical oceanographer and climate scientist, says the project is looking at how currents distribute heat in the ocean, a key factor in understanding climate.
+"And when the heat is released back into the atmosphere it affects the climate in that location," he says.
+Measurements of the ocean temperature suggests that 84% of total heat increase of the Earth in the past 50 years has been stored in the ocean, says Rintoul. 
+In particular, he is studying 'fronts'. These are areas of strong current within the gigantic Antarctic Circumpolar Current, which links all the world's oceans.
+"They're like rivers in the sea," he says.
+By comparing maps of penguin and seal tracks with maps of the fronts, the researchers found the animals like to feed near the fronts which make them perfect spies for scientists.
+
+Bacteria remove gold from soil and deposit it on grains where they live, scientists say
+Australian scientists have found the strongest evidence so far that bacteria play a key role in forming gold grains and nuggets.
+They have found bacteria that remove gold from the soil and deposit pure grains of it around them.
+Researcher Dr Frank Reith from the CRC for Landscape Environments and Mineral Exploration, and colleagues gathered their evidence at two separate mines and publish their results today in the journal Science.
+At the Tomakin mine on the south coast of New South Wales and the Hit or Miss mine in tropical north Queensland, most gold is hidden away in quartz veins, in amounts that are invisible even to high-powered microscopes.
+But the soil above the mines also contains grains and nuggets of gold that have somehow found their way out of the quartz. 
+"There are a probably a lot of processes involved," Reith says.
+He and other scientists have long suspected that bacteria play a part, but it's an idea that has generated some scepticism.
+To test the theory, Reith sifted the soil above the mines and collected gold grains 0.l-2.5 millimetres across, and then subjected them to several experiments.
+First, Reith looked at the grains under a high-powered electron microscope to confirm that they contained bacteria-shaped bubbles of gold.
+"They're little lumps on the surface," Reith says.
+Next, he looked for organic matter on the grains, as evidence that bacteria had been growing on their surfaces. 
+Finally, he used a technique called polymerase chain reaction to look for bacterial DNA on the surfaces of the grains to show that living bacteria are still there.
+"The DNA would have degraded if the bacteria weren't around any more," Reith says.
+About 80% of the grains had living bacteria on them, Reith says. And the only bug that was found on all those positive samples was Ralstonia metallidurans.
+"These grains come from areas that are almost at the opposite ends of Australia," Reith notes. "We were pretty happy with that."
+Reith thinks the Ralstonia bacteria play an important role in the microbial ecosystem in soil, helping to rid it of the soluble gold that most other species find toxic. 
+"This is the guy whose job it is to get the toxic gold out of the environment so the other bacteria can live a happy life," he says.
+In the future, the gold-loving bugs could prove a boon to industry, Reith says. Perhaps they could be used to improve gold processing, or even be useful as a marker for the presence of gold that's otherwise invisible.
+
+The researchers could not directly link smoking marijuana with lung cancer. But they found evidence of precancerous changes in the lung like oxidative stress, damaged tumour-fighting cells, and DNA and tissue changes
+Smoking marijuana can cause changes in lung tissue that may promote cancer, according to a review of decades of research on marijuana smoking and lung cancer. 
+Still, it is not possible to directly link pot use to lung cancer based on existing evidence. 
+Dr Reena Mehra of Case Western Reserve University in Cleveland, Ohio and her colleagues publish their review in the current issue of the Archives of Internal Medicine.
+"Given the widespread use of marijuana, its use for what are believed to be medicinal purposes, and the increasing abuse and dependence on this substance, it is important to examine potential adverse clinical consequences," the researchers write.
+To investigate whether marijuana smoking might lead to precancerous changes in the lungs or lung cancer, Mehra and her team reviewed 19 studies.
+Analyses of sputum and lung tissue performed in some of these studies found more cancer-promoting changes in pot smokers than in cigarette smokers or non-smokers.
+These changes included oxidative stress, dysfunction of tumour-fighting cells, changes in tissue structure and DNA alterations, the researchers report. 
+But none of the studies they analysed found evidence that marijuana smoking actually caused lung cancer, after factoring in the effects of tobacco use. 
+"We must conclude that no convincing evidence exists for an association between marijuana smoking and lung cancer based on existing data," Mehra and her team write.
+Increased risk
+Nevertheless, the researchers add, the precancerous changes seen in studies included in their analysis and other factors do suggest that smoking pot could indeed boost lung cancer risk.
+Other factors that could make pot smokers prone to lung cancer, the researchers say, include the fact that they generally inhale more deeply and hold smoke in their lungs longer than cigarette smokers, and that marijuana is smoked without a filter.
+It is known, they add, that marijuana smoking deposits more tar in the lungs than cigarette smoking does. 
+The failure to find a marijuana-lung cancer link may have been due to methodological flaws in existing research, rather than the absence of such a link, the researchers say.
+Doctors should advise their patients that marijuana does indeed have potential adverse effects, they conclude, including causing precancerous changes in the lungs. 
+For more information about drugs and their side-effects, see the DrugInfo Clearing House website run by the Australian Drug Foundation.
+
+Helper with 30-day-old pups
+Meerkats actively teach their young how to catch and eat their prey, UK researchers say in a study that is one of the first to show such complex animal behaviour. 
+While animals are known to learn from one another by watching, the team at the University of Cambridge says it has demonstrated that the animals actually teach, as defined by clear principles. 
+Older meerkats will bite the stinger off a live scorpion and give it to a youngster to kill and eat.
+And if the pup fails to do the job before the prey can crawl away, the older meerkats nudge it back, Alex Thornton and Katherine McAuliffe report. 
+Older meerkats, not necessarily the parents, will watch youngsters to see how they are doing, the researchers report today in the journal Science. 
+Meerkats are a type of mongoose and live in groups of three to 40 in dry regions of southern Africa.
+Each group includes a dominant male and female who produce 80% of the pups, and older animals that help to watch over and rear the young. 
+The animals rely on hard-to-catch prey such as grasshoppers and various species of scorpions, including poisonous ones. 
+In the wild
+The researchers watched 13 different groups of meerkats as part of the Kalahari Meerkat Project, in South Africa's Kuruman River Reserve. 
+They used accepted criteria to define teaching: that an individual modifies its behaviour only in the presence of a naive observer, that the 'teacher' gets no benefit from its actions and in fact may lose opportunities to forage itself, and that the 'student' learns more rapidly than it would have on its own. 
+"Teaching is ubiquitous in human societies, but although social learning is widespread in other species, it is not yet clear how commonly teaching is involved," the researchers write. 
+The meerkats demonstrate clearly that they teach, and do not merely allow the pups to learn by observing, Thornton and McAuliffe say.
+"A greater understanding of the evolution of teaching is essential if we are to further our knowledge of human cultural evolution and for us to examine the relations between culture in our own species and cultural behaviour in other animals," Thornton says.
+
+The Larsen ice shelf, seen here collapsing in 2002, may be under greater threat from faster westerly winds over Antarctica
+Heat-bearing westerly winds have picked up speed in the past 50 years are likely to be contributing to the melting of Antarctica's Larsen ice shelf, say scientists.
+Meteorologist Professor John Turner of the British Antarctic Survey says the biggest change in the wind speed occurs in the southern hemisphere summer.
+"The ice there [on the ice shelf] is melted most in summer and that is the season when the winds are increased," says Turner, who gave a keynote talk at the Scientific Committee on Antarctic Research meeting in Hobart this week.
+Antarctica generally has lower temperatures and pressures than areas at more northern latitudes, like Australia. 
+This differential generates storms that take warm air south and cold air north.
+Turner says that over the past 50 years the differential appears to have increased, and this has increased the speed of westerly winds over the Southern Ocean by an average of a few knots.
+The increase in speed means the westerlies are now blowing over the Antarctic Peninsula rather than around it, bringing destructive warm air onto the Larsen ice shelf to the east of the peninsula, says Turner.
+He says the pick-up in the westerlies will also influence climate elsewhere on the planet by driving the Antarctic Circumpolar Current faster. The current shifts vast amounts of water and plays a major role in global heat transfer.
+Beyond natural variability
+While the pressure and temperature differential between Antarctica and more northern latitudes goes up and down in natural cycles, Turner says climate models suggest recent changes are "exceptional" when compared to the past 1000 years.
+"What we've seen over the last 50 years is larger than anything in these models," he says. "That suggests that man is playing a part in this."
+Turner says an increase in the speed of westerlies ties in with the prediction of more extreme storms in a warming world.
+And he says models also support the idea that increasing greenhouse gases are causing the westerlies to increase, although exactly how they are doing so is not known.
+Research on the increasing speed of westerlies and their role in melting the Larsen ice shelf is due to be published soon in the Journal of Climate.
+Double whammy
+Turner says the ice shelves are very sensitive to climate change because they have ocean beneath them and air above.
+The warm westerlies blowing over their top and the warming oceans flowing beneath are "like a double whammy" for the ice shelves, he says.
+Melting ice shelves in themselves don't affect sea level because they are already floating, but it's their role in holding back ice flowing from the main part of the peninsula that is in jeopardy.
+"If you take away these ice shelves, the danger is the ice from the interior could start flowing faster," says Turner.
+He says preliminary research suggests ice is already flowing off the peninsula faster than in the past.
+Antarctica holds 90% of the world's fresh water in the form of ice, says Turner, and if all of this melted there would be a 65-metre rise in sea level. 
+The current sea level is rising at 3 millimetres per year.
+
+As long as water is good enough to drink, researchers say it's good enough to clean uninfected wounds
+Medical workers in disaster areas no longer have to wait for sterile equipment before they clean and dress wounds, thanks to Australian research.
+Professor Rhonda Griffiths, of the University of Western Sydney's Centre for Applied Nursing, says as long as water is good enough to drink, evidence suggests it will be good enough to clean uninfected wounds.
+"We've demonstrated that some of the traditional ways of doing dressings are unnecessarily expensive and labour intensive," says Griffiths.
+She adds that if there is any doubt that the tap water is suitable for drinking, it can be boiled before use.
+Griffiths and colleagues recently completed a systematic review of evidence for the Cochrane Collaboration comparing the use of saline versus tap water to clean uninfected wounds. 
+The review found that washing wounds, including leg ulcers, with water did not show an increase in infection or decrease in healing time, compared to using saline, she says.
+As a result, the Cochrane Collaboration is now recommending tap water is used to clean wounds in developing countries and disaster zones, says Griffiths.
+In the community
+Community nurses, who treat people at home, first triggered the investigation into the use of tap water to clean wounds, says Griffiths.
+While hospitals routinely use saline or sterilised water to clean uninfected wounds, community nurses have traditionally relied on people to simply shower before they dress their wounds.
+"So in hospitals you had one practice," says Griffiths. "And the community had another."
+Both practices were based on tradition rather than evidence, she says.
+One of the studies included in Griffiths' Cochrane review was carried out by her team.
+It was a six-week double blind, randomised controlled trial in southwestern Sydney that studied the healing and infection rate in 49 wounds of 35 patients washed with saline, compared with equivalent patients who were washed with tap water.
+"We found that there was no difference," she says.
+"That tells us that if you have got clean tap water that you can drink, it is perfectly safe to wash wounds with that tap water if those wounds aren't infected."
+Griffith says the research is changing the way we think about managing some types of wounds.
+"It's the cleanliness rather than the sterility [that's important]," she says.
+Better for patients and cheaper
+Griffiths says washing wounds with tap water would save money in hospitals, especially the cost of the disposable sterile equipment that is required when using saline.
+Patients also prefer washing with water, she says, because they can get out of bed and take a shower.
+While tap water may be safe and effective, Griffiths still wants to confirm the findings and find out if saline offers any advantages by carrying out a much larger randomised controlled trial.
+She has applied for funding from the National Health and Medical Research Council to carry out a trial involving 400 wounds.
+
+Seabirds, like this grey-headed albatross, can be caught as bycatch. But could a stinky repellent ward them off?
+An old fishermen's remedy for preventing seabirds from becoming bycatch turns out to be true, according to a new study on the effectiveness of shark liver oil at warding off birds.
+Using the stinky oil might help save seabirds, which often have fatal interactions with longline fisheries.
+These fisheries use a line up to 100 kilometres long, often with additional branching lines.
+Each line is rigged with hundreds or even thousands of barbed, baited hooks.
+Seabirds, including some endangered species, often dive for the bait and fish. The birds can become entangled in the lines or injured, sometimes fatally, by the hooks.
+Alex Aitken, a New Zealand fisherman for over two decades, uses the traditional shark liver oil as a deterrent.
+Sharks themselves are bycatch in the snapper longline fishing industry, but government and industry regulations monitor their numbers in New Zealand.
+Aitken drips the oil into water around fishing boats to deter the birds. In 2003, he entered his concoction in the SEO/BirdLife International competition for bycatch reduction. He won.
+To test the oil, scientists Johanna Pierre of New Zealand's Department of Conservation and Wendy Norden of wildlife conservation group Audubon California conducted experiments off New Zealand's North Island. The seabird community there includes the endangered black petrel.
+The researchers dripped the shark liver oil from a plastic container at the stern of their vessel, while they set out 200 baited hooks on lines.
+As controls, they later conducted the same test using vegetable oil and seawater.
+The shark liver oil did not affect fish catches, but it did dramatically reduce the number of times seabirds dived for the hooks.
+For example, after nine minutes, only two or so birds went for the hooks when shark oil was present. Around 40 birds dived when seawater was used, while more than 50 took dives during the vegetable oil trial.
+Pierre and Norden think the birds might even have been attracted to the vegetable oil, but the shark liver oil was a successful repellent.
+Their findings are published in the July issue of the journal Biological Conservation.
+"We are not sure what happens when the seabirds smell the oil," Pierre says.
+"However, when the oil is released at the stern of the vessel, the effect ... is next to immediate. The birds disperse away from the vessel, sufficiently far that they can't be seen. One or two birds may come in from time to time and do wide looping flights around the vessel, but they typically don't land or stick around for long."
+The repellent seems to have more to do with the noxious smell of the oil, or its consistency in the water, rather than the birds' fear of sharks.
+"I think it's unlikely that they have a negative reaction to the smell of sharks per se. This is because the birds have no hesitation to eating shark livers when they are whole and they can also eat shark waste readily," Pierre explains.
+The deterrent only appears to work as long as the dripping is continuous. Once the oil flow stops, Pierre says the birds "somehow cue into the fact that the vessel area is now attractive/interesting, not oily/nasty".
+Though shark liver oil is a natural product, it may be problematic to introduce large amounts into marine environments.
+Pierre and Norden hope the effective ingredients in the oil may be identified and isolated. It could be that these ingredients may be found in products other than shark liver oil, but this has yet to be determined.
+In the meantime, the scientists suggest caution in using large amounts of the oil, and hope alternatives such as aerosol mists of the effective ingredients can be developed in the long run.
+
+Can't a man pee in peace? Not in the US, where urinals are broadcasting public health messages
+If you're a man and the urinal you're standing over is talking to you, one of two things is probably happening: you're really drunk or the owner has installed a talking urinal in the bathroom.
+Let's say, for your sake, it's the receptacle. Then it must be the Wizmark Urinal Communicator, a waterproof, disposable drain cover embedded with electronics that senses a visitor and then relays an audio message.
+The device can be programmed to play anything from beer commercials to public service announcements promoting responsible drinking.
+"It functions as a point of information and amusement for the male visitor," says its inventor Dr Richard Deutsch, a chiropractor and bioengineer, as well as the founder of US company Healthquest Technologies.
+Deutsch conceived the idea while on a business trip in Washington DC. 
+On a pit stop to an airport toilet, he realised that he was staring down at a drain for about the same length of time as it took to play a commercial.
+He worked as an inventor for several years to develop and patent a prototype and about one year later was under way with mass production.
+How does it work?
+The communicator is a plastic device designed to fit over the drain of standard-sized urinals.
+Not only does the device act as a deodoriser with a disinfectant base, it also contains a proximity sensor that detects someone approaching within about 30 to 60 centimetres.
+A few seconds after detection flashing lights and a prerecorded audio announcement plays.
+The device has a 9 centimetre diameter display area containing a lenticular screen that features multiple images or text that, as the person moves toward the urinal, appear to change from one graphic to the other.
+Just in case you are drunk, the Wizmark doesn't want to let you get away without a warning. Aside from advertising, it's being used to tout anti-drink-driving, safe sex, and anti-drug messages.
+Out in the field, erm, the toilet
+Safety officials in Nassau County, New York, have already acquired 100 copies of the Wizmark, funded by fines from those caught driving while intoxicated, as part of a pilot program to be distributed free to bars, clubs and restaurants.
+"This is perfect for the target audience we try to reach all of the time and have difficulty doing it," says Joanne McGarry, the coordinator of Nassau County's anti-drink driving program.
+McGarry is asking participating store-owners to fill out a questionnaire about the Wizmark, to gather information about its usefulness.
+Deutsch is also working with various states and their associated health agencies on devices featuring cartoon characters or sports heroes to promote anti-drug messages in schools.
+
+The large ground finch (Geospiza magnirostris) competed with its smaller-beaked cousin for food. But that balance changed once the climate shifted, triggering rapid evolution
+A Galapagos finch that helped reveal the origins of species to Charles Darwin has now undergone a spurt of rapid climate-driven evolution, biologists report.
+The medium ground finch (Geospiza fortis), of Daphne Island was nudged, and then shoved, to evolve a smaller beak.
+This happened by the combination of competition from another finch that arrived on the island more than 20 years ago and more recent drought conditions.
+"It happened very fast," says biologist Professor Peter Grant of Princeton University.
+He and Dr Rosemary Grant publish their discovery in the latest issue of the journal Science.
+In fact, it happened in a single bird generation, Grant explains.
+The evolutionary nudging began when some larger finches settled on Daphne during an exceptionally wet El Ni&ntilde;o in 1982. 
+In the years since, the larger G. magnirostris finches have been eating most of the larger, thorny seeds of the island's puncture vine plants and steadily pushing the smaller finches to rely on smaller seeds from other plants.
+As a result, G. fortis birds with smaller beaks that did not compete with the larger birds did better, and were more likely to have offspring. That essentially enriched the gene pool with small beak genes and led to more G. fortis with smaller beaks.
+But the matter really came to a head in 2003 and 2004, when little rain fell on the island and seeds of any kind were scarce.
+"Most of the birds that had large beaks before the drought disappeared," says Grant. That included almost all of the recently arrived G. magnirostris and any remaining G. fortis with especially large beaks.
+The only birds that survived enough to mate and produce offspring in 2005 were the G. fortis with smaller beaks and an ability to exploit small seeds like those of the drought-tolerant Optunia cactus.
+In Darwinian jargon, the small-beaked birds were naturally "selected" for perpetuating the species, just as a dog breeder might select for speed in a greyhound.
+"For years, this has been the classic textbook example of rapid evolution," says Professor David Skelly, an ecologist and researcher of rapid evolution at Yale University, referring to the competitive pressure on G. fortis by the larger beaked G. magnirostris.
+"When I was a student, [Grant's] work was sometimes taught as the exception to the rule," says Skelly.
+That is, normally evolution is thought of as slow and gradual in large animals like fish, birds, reptiles and mammals.
+Beak sizes changing measurably in just decades seems awfully fast. 
+The Galapagos finches were considered an extreme case of quick evolution caused by an extreme environment.
+"Now it appears that the Grants' work shows a pattern that is likely to be widespread," says Skelly, who has studied rapid evolution of amphibians in response to global warming.
+"Environmental changes severe enough to cause sharp population declines, as seen with the finches, are also selection events."
+As more and more species undergo the stresses of climate change, more cases of rapid evolution can be expected, Skelly says.
+It's not likely to save most species facing the climatic bottleneck, of course, but it does give a few a fighting chance, he explains.
+It's not unusual
+"I don't think there is any reason to suspect this is an unsual occurrance," says Australian biologist Professor Richard Shine of the University of Sydney.
+Shine has charted the rapid evolution of longer legs in invasive cane toads in Australia, as well as adaptive changes in native snakes where the toads have invaded over the past few decades.
+We'd see more evidence of rapid evolution if there was more support for long-term field studies like that of the Grants' 30-year work on the finches, he says.
+"It's incredibly difficult to maintain these long-term studies."
+
+Implanting false memories can have health benefits like preventing alcohol abuse. But is it ethical to brainwash people?
+Implanting false memories of a bad experience with alcohol could prevent people abusing alcohol in later life, a Canadian researcher says.
+Dr Dan Bernstein from Kwantlen University College, shows that if people are led to believe they once drank themselves sick it can affect their taste for a particular drink.
+He presented the unpublished research, conducted over the past year, at the 4th International Conference on Memory in Sydney today.
+In the study 142 people aged 18-20 were told they had had a bad past experience with alcoholic drinks including rum.
+"We wanted to know whether there were consequences to false memory and we looked at whether we could increase people's confidence that they got sick drinking rum some time in their past," Bernstein says.
+"What we find is that if you've increased your confidence that you've got sick drinking rum, you now give rum less preference."
+Rewriting the past
+Participants' memories were manipulated by telling them that a computer had generated a personal profile based on a questionnaire about past eating and drinking habits.
+They were told they had become sick on rum in the past and they were asked to elaborate on that experience.
+About a quarter of the participants became more confident that they had actually been sick on rum.
+"We find that between 30 and 40% increased their confidence for the critical item in comparison to a control group," he says.
+When they were asked to rate how much they liked rum they rated it less highly than before their memories were manipulated.
+Ethical issues
+Bernstein says if it can be shown that implanting false memories can have a long-term effect on putting people off certain alcoholic drinks it could be a useful deterrent to alcohol abuse.
+"If we showed that it had a lasting behavioural effect then it could possibly have some preventative utility, but that's a long way off," he says.
+Professor Mike Toglia, a US expert in false memories from the State University of New York, who wasn't involved in the research, says Bernstein's work offers a new application for this field of memory research.
+He acknowledges there are ethical issues about brainwashing.
+"There's always been the concern that implanting false memories is a form of brainwashing and some people believe that maybe this kind or research should be stopped for that reason," he says.
+"But I think the good that can be done can outweigh the risks."
+Beating obesity
+Manipulating memory could also be used to prevent overeating, Bernstein says.
+But prior bad experiences don't create an aversion to all foods and drinks, Bernstein says, only those with a distinct or unusual flavour.
+"With some drinks and some food you may have got sick but it doesn't seem to have this imprint, this lasting effect," he says.
+He says his previous research managed to induce an aversion to strawberry ice cream, but didn't work so well when it came to chips. 
+"We couldn't turn them off potato chips," he says.
+"In fact we got a little rebound and they thought 'give me more!'"
+
+Ahh, I remember this ...
+Songs we hear as teenagers tend to remain lifelong favourites because they become hardwired into our memory during a critical time, a memory conference has heard.
+That critical time is known as the reminiscence bump, says Steve Janssen, a PhD student at the University of Amsterdam.
+Janssen presented his research into how we form memories of our favourite music, books and movies at the 4th International Conference on Memory in Sydney this week.
+He says the reminiscence bump can be partly explained by what's called differential encoding, or an ability to store events better during early adulthood.
+"You recall more memories from the period of 10 to 25 [than previous or subsequent periods] and the bump has a peak between 16 and 20," he says.
+"The brain works at its optimum in that period. It's a sponge and it soaks up everything."
+We also learn languages and musical instruments best during this time.
+But attachment to songs isn't all about the reminiscence bump, he says.
+We also form a particularly personal connection with music from our teen years because we tend to listen to the same songs over and over, his research indicates.
+What's your favourite?
+Janssen found that when asked to rate their three favourite records, movies and books, participants in his study overwhelmingly chose items they listened to, watched or read between the ages of 16 and 21.
+While music preferences were strongly linked to the reminiscence bump, favourite books and movies were more likely to have been read or viewed recently.
+This is because we usually only read books once or twice, and see movies a handful of times, but can be exposed to the same song many times, he reasons.
+"All distributions showed a reminiscence bump so there's evidence that people store events better in their teens," Janssen says.
+"However, I also found a larger recency effect for books and a larger reminiscence bump for records ... so I suggest a kind of interaction between those two mechanisms.
+"The results suggest that differential encoding initially causes the reminiscence bump, but resampling strengthens the bump."
+Janssen's presention was based on data gathered through an online survey between January 2005 and April this year.
+He analysed results from 1500 participants around the world with an average age of 36, including 23 Australians.
+You can participate in the study here.
+
+The epicentre of the 7.2-magnitude quake, south of the Indonesian island of Java
+At least 105 people were killed when an undersea earthquake unleashed huge waves on the Indonesian island of Java, echoing the devastating 2004 Asian tsunami, the Red Cross said today. 
+After a strong 7.2-magnitude quake convulsed the seabed off Java's south coast, waves up to 3 metres high wrecked buildings and sent boats crashing ashore, prompting thousands of residents to flee in panic. 
+Tsunami alerts were issued for parts of Indonesia and Australia, but they did not reach the victims, as there was no early warning system working in the disaster zone, according to an official at the geophysics agency in the capital Jakarta. 
+"There are 105 people dead from 10 regencies, 148 people are injured and 127 still missing," says Putu Suryawan, the official at the Indonesian Red Cross disaster centre, adding that 2875 people had been displaced from their homes.
+"Possibly this number could rise because many people are still missing." 
+At least five aftershocks rattled the area after the quake, which hit around 3:19 pm local time on Monday (08:19 UTC), with the epicentre in the sea off Pangandaran southeast of Jakarta, according to Indonesia's seismology centre. 
+Indonesia was the nation hardest hit by the devastating December 2004 Indian Ocean tsunami, which killed around 220,000 people across the region.
+"We still don't have a tsunami early warning system in place," says an official at the geophysics agency in Jakarta.
+Indonesia's 17,000 islands sit on the Pacific 'Ring of Fire', where the meeting of continental plates causes high volcanic and seismic activity. 
+Both the Pacific Tsunami Warning Center in Hawaii and the Japan Meteorological Agency issued tsunami alerts for parts of Indonesia and Australia after the quake hit. 
+A tsunami warning was also issued by local authorities for India's Nicobar islands, but no immediate damage was reported there or in Australia. 
+Police on Christmas Island, an Australian territory south of Indonesia, say there was no damage there.
+
+Surgical staff leave behind a sponge or scalpel in one in 10,000 operations. But new technology may change that
+Surgeons may be able to use radio-tag technology to detect sponges they've inadvertently left inside their patient, a small US study suggests.
+Researchers at Stanford University School of Medicine tested sponges embedded with radio frequency identification (RFID) tags that were left in eight patients having abdominal or pelvic surgery.
+Doctors and nurses then waved a detector wand over the patients, which beeped when it found the sponges.
+The wand detected the tagged sponges every time, in an average 3 seconds. There were also no false alarms, when the device bleeped but there was really no sponge there.
+But the researchers say the system is still prone to error, especially if people wave the wand too far away from the body, or don't scan the correct part of the body.
+The study is published this week in the Archives of Surgery.
+Alex Macario, a physician and professor of anaesthesia who led the study, says the future will probably see a combination of tags and other techniques such as counting instruments and sponges before and after an operation.
+"We need a system that is really fail-safe; where, regardless, of how people use this technology, the patient doesn't leave the operating room with a retained foreign body," he says.
+An earlier study found that medical personnel left foreign objects, most often sponges, inside a patient's body in one out of every 10,000 surgeries causing complications and even death. 
+RFID tags are used commercially for uses ranging from tracking luggage and preventing currency from being counterfeited to preventing shoplifting to collecting road tolls.
+The study was funded by the National Institutes of Health and by a grant from the Small Business Innovation Research Program, using sponges developed by ClearCount Medical Solutions in Pittsburgh. 
+Macario has no financial interests in that company but two of the study's co-authors own several patents related to tagged sponges and work for the Pittsburgh company.
+
+If you're confronted with a familiar situation that seems oddly unrecognisable, you could be suffering from jamais vu
+The first scientific study of jamais vu, the reverse of d&eacute;j&agrave; vu, has shown that the experience exists and can be induced, an international memory conference has heard.
+Jamais vu literally means "never seen" and describes the sense of unfamiliarity in the face of very familiar things or situations, says UK researcher Dr Chris Moulin of the University of Leeds.
+"If you stare at a word, for instance, it loses its meaning," says Moulin, who adds that an estimated 60% of people have experienced jamais vu.
+He presented his research for the first time at the 4th International Conference on Memory in Sydney this week.
+Jamais vu is the opposite of d&eacute;j&agrave; vu, or "already seen", which is a sense of familiarity about an unfamiliar object, or the feeling that "I've been here before".
+"Musicians can get [jamais vu] in the middle of playing a familiar passage. It's the sensation where you wake up in the morning and turn to the person next to you and feel that they're a stranger," says Moulin.
+"[It can also occur] when you look at a face for too long and it begins to look strange, or when you're in a familiar place but think 'I don't know where I am', for a brief, fleeting moment."
+Jamais vu was first recognised about 100 years ago when it was regarded as something of a "gentleman's intrigue", Moulin says.
+But it has never been systematically studied in a laboratory until now.
+Brain fatigue
+Moulin says his study shows it's possible to induce jamais vu by what's known as semantic satiation, which occurs when the brain becomes fatigued in a specific way.
+He asked 92 subjects to write common words such as "door" 30 times in 60 seconds.
+When they were later asked to describe their experiences, 68% showed signs of jamais vu.
+For example, after writing "door" over and over again some participants reported that "it looked like I was spelling something else", it "sounded like a made-up word" and "I began to doubt that I was writing the correct word for the meaning".
+Some thought they had been tricked into thinking it was the right word for a door.
+"If you look at something for long enough the mind gets tired and it loses it's meaning," Moulin says.
+Moulin says studying jamais vu will help researchers better understand psychiatric disorders like schizophrenia or Capgras delusion, where people believe someone they know very well has been replaced by an impostor.
+"It suggests that this is the normal process that might go wrong in these people, they might just have chronic jamais vu," Moulin says.
+His latest research aims to induce jamais vu and monitor what actually goes on in the brain using neural imaging.
+
+So, tell me about yourself ...
+If you go out on a first date with someone and they only tell you good things about themselves it's not because they're being dishonest. They've genuinely repressed their bad points, a memory conference has heard.
+Celia Harris, an Australian PhD student at the University of New South Wales, has demonstrated that when we're courting a romantic partner we are likely to remember only the good things about ourselves while forgetting the bad.
+Harris asked 86 male and female subjects to imagine they were going on a date and to list 10 positive and 10 negative things that they would recount about themselves.
+"We asked them to think, you're going out with this person you've really liked for a long time, you want them to think you're funny, smart, clever, a nice person, so try and come up with things that would impress them," she says.
+Positives included getting on well with their mothers, having lots of friends and helping elderly ladies carry bags.
+Negatives included getting falling-down drunk, failing exams or getting into fights.
+Accentuate the positive, eliminate the negative
+After completing a series of tasks and undergoing a brief distraction period they were asked to recall all the negative and positive points about themselves.
+While the participants remembered all the positives, they struggled to remember all the negatives.
+Harris says her study demonstrates our uncanny ability to selectively forget certain things if we have a motivation, such as impressing a new love interest.
+"It confirms that motivation drives what we remember and forget," she says.
+"It supports the idea that there are selective phases of autobiographical memory [and]  
+depending on the situation we'll facilitate certain memories for retrieval and inhibit or block the retrieval of others."
+Her study is reported in a poster presentation at the 4th International Conference on Memory held in Sydney this week.
+Choosing what to remember
+Harris based her study on retrieval-induced forgetting, which says that repeated recall of certain items can impede our ability to remember others.
+Participants were split into two groups, with one required to concentrate on five negative points in their list and the other asked to concentrate on five positive points.
+While the positive group remembered all their positive memories, the negative group forgot half the negative.
+This demonstrates that positive memories seem to be protected against retrieval induced forgetting, Harris says.
+
+Tsunami-hit Pangandaran beach.  The death toll rose towards 300 on Tuesday after a strong undersea earthquake triggered a tsunami that smashed into fishing villages and resorts (Reuters/Dadang Tri)
+Indonesians fleeing this week's tsunami that lashed the south coast of Java had no warning, with a countrywide early warning system not due to be in place until 2009, officials say.
+Plans for such a system in Indonesia were drafted in the wake of the devastating 2004 Asian tsunami, but only two out of 25 planned sensor buoys have been deployed so far, off Sumatra, not Java, officials say. 
+"Our system is not yet working properly. We are still developing a communication system especially for the regions," says Fauzi, an official working on the early warning project from the meteorology agency in Jakarta.
+He says only two sensor buoys were in place on Sumatra but that nothing had yet been installed off Java. 
+Edi Prihantoro, from Indonesia's Ministry of Science and Technology, says even those two sets of buoys and ocean-bottom pressure sensors, activated off western Sumatra last November by Indonesian and German scientists, were not working. 
+"According to a grand scenario we will have up to 25 buoys that can monitor ocean phenomena, but until now we have deployed only two buoys. They have some problems and are on land," he says. 
+The system was slated to be in place by the end of 2008, he says. 
+A lack of funds to buy and maintain the buoys was delaying the implementation of the system, he says, arguing that not only Indonesia should pay for its upkeep. 
+"We still are discussing budget and maintenance. But I think other countries must also be taking care of it. They get all the ocean data from us, it seems unfair if they don't take responsibility for that," he says. 
+Prihantoro says the German and Chinese governments had so far donated funds for the system but that it would be expensive to set up across Indonesia.
+If installed as planned, buoys along Indonesia's vast archipelago working in conjunction with more than 100 seismographs would detect the speed of seismic waves to determine whether there was a risk of a tsunami. 
+Data would be analysed and relayed automatically through mobile phone text message or email to officials who could then inform residents. 
+But getting the message through to them could still prove a challenge.
+Even if Java had had a system in place on Monday, it is doubtful many of the small fishing villages along Java's south coast would have received any SMS warnings as mobile reception is limited and many people are too poor to own phones. 
+"It is not enough to warn people through TV and radio. The problem is direct communication to communities on the ground," says Fauzi. 
+He says the most direct way to alert residents would be sirens on beaches. 
+"This year we will build three siren systems in Aceh, West Sumatra and Bali. We will build one in Java next year," he says. 
+Indonesia sits on the so-called Pacific Rim of Fire, where the meeting of continental plates causes high volcanic and seismic activity. 
+It lacked a warning system when a massive quake hit off Sumatra on 26 December 2004, unleashing a tsunami that swept up to 7 kilometres inland and killing some 220,000 people in 11 countries around the Indian Ocean.
+
+In less than 15 generations, more than half the population of England had Anglo-Saxon genes
+The Anglo-Saxons who conquered England in the 5th century set up a system of apartheid that enabled them to master and outbreed the native British majority, according to gene research. 
+In less than 15 generations, more than half of the population in England had the genes of the invaders, investigators say. 
+"The native Britons were genetically and culturally absorbed by the Anglo-Saxons over a period of as little as a few hundred years," says Dr Mark Thomas, a University College London biologist. 
+"An initially small invading Anglo-Saxon elite could have quickly established themselves by having more children who survived to adulthood, thanks to their military power and economic advantage. 
+"We believe that they also prevented the native British genes getting into the Anglo-Saxon population by restricting intermarriage in a system of apartheid that left the country culturally and genetically Germanised," he says. 
+"This is what we see today, a population of largely Germanic genetic origin, speaking a principally German language." 
+Thomas believes the study, published in the journal Proceedings of the Royal Society B, answers key questions about one of the turning points in European history. 
+What happened after the Romans?
+The Anglo-Saxons, Germanic tribes who lived in present-day Germany, northern Holland and Denmark, invaded Britain in 450 AD after the fall of the Roman empire.
+They conquered England but were unable to penetrate far into the Celtic fringes of what are now Wales and Scotland. They coincidentally prompted an exodus of Britons to what is now Brittany, France.
+The population of England at that time was probably around two million while the number of Anglo-Saxons was minute: the lowest estimate puts the number of migrants at less than 10,000 some 200 years after the invasion, although others put it at more than 100,000.
+How could such a tiny minority have ruled a country so emphatically? How could it skirt assimilation with the native British majority and impose a language, laws, economy and culture whose stamp is visible today? 
+The answer, suggest Thomas and colleagues, is an "apartheid-like social structure" that enshrined Anglo-Saxons as the master and the native Britons (called "Welshmen", from the Germanic word for slave) as the servants. 
+Historical evidence
+Evidence for this comes from ancient texts, including the laws of Ine, the late 7th century ruler of Wessex, an Anglo-Saxon kingdom in western England. 
+Ine set down payments of 'wergild', or blood money, that was payable to a family for the killing of one of its members in order to prevent a blood feud. 
+If an Anglo-Saxon was killed, the wergild was between two and five times more than the fine payable for the life of a "Welshman" of comparable status. 
+Burial sites also provide a pointer about economic and social disparity. 
+The skeletal remains of men believed to be Anglo-Saxons are often found alongside a weapon or other precious artefacts, whereas those of native Britons are usually weaponless and have only one or two objects. 
+In previous work, Thomas' team compared the gene pool among native, white Englishmen in central England today and counterparts in the ancestral lands of the Anglo-Saxons. 
+They found that the two groups shared between 50 and 100% of telltale variations in the male sex chromosome Y. 
+Genes to map growth and decline
+In the latest research, he used computer simulations to try to explain how segregation would have enabled the Anglo-Saxons to flourish and the native Britons to decline. 
+The computer model uses various scenarios involving the size of the immigration influx, different ethnic intermarriage rates and the reproductive advantage of being Anglo-Saxon, with more wealth and resources. 
+Apartheid is best known today for the notorious racial segregation that prevailed in white-minority South Africa. 
+But the authors point out that there are many other examples in history, when conquerors or settlers used such controls to avoid assimilation, nurture their identity and maintain their political, military or economic supremacy over an ethnic majority. 
+By the time of King Alfred the Great in the 9th century, the differences in legal status between Anglo-Saxons and Britons had faded out altogether. 
+Two centuries later, the Normans invaded England and imposed their own apartheid, giving themselves higher legal status than the Britons and allowing Norman men to marry native women but preventing native men from marrying Norman women.
+
+Sunlight can be a scarce commodity in Antarctica and that's affecting vitamin D levels in some researchers
+Scientific researchers spending winter in Antarctica might be at increased risk of osteoporosis unless they take vitamin D supplements, new research suggests.
+A pilot study presented last week at the Scientific Committee on Antarctic Research meeting in Hobart, suggests some researchers who spend the winter in Antarctica have low levels of vitamin D, which is making their bones weaker.
+"Their bone may resorb more calcium and get weaker which can lead to a potential increase in osteoporosis in the long term," says researcher Dr Jeff Ayton, chief medical office of the Australian Antarctic Division.
+Vitamin D is a hormone produced by the action of solar ultraviolet radiation on the skin and is essential for a number of processes including bone metabolism.
+Lack of exposure to sunlight decreases vitamin D synthesis and increases bone turnover and bone loss.
+Ayton says expeditioners who spend the winter in Antarctica have very little exposure to sunlight for seven to nine months.
+But in summer they are at high risk of sunburn unless they cover up with hats and sunscreen.
+Ayton and colleagues studied the vitamin D levels and skeletal response to sunlight deprivation in 57 healthy adults (with an average age of about 38 years) during their winter in Australia's Antarctic program.
+Participants were also followed up after leaving Antarctica and returning to a more temperate climate.
+Bone resorption, but not formation, was elevated during the period of sun deprivation, Ayton and colleagues report.
+But they have yet to determine the long-term effect on bones, such as the increased risk of osteoporosis.
+It may be that researchers need to receive supplements of vitamin D, says Ayton, or screened for vitamin D levels before they head south.
+Ayton says medical researchers are concerned that many people in the general population may have subclinical vitamin D deficiency depending on the latitude of where they live. 
+And he says the lower acceptable limit of vitamin D may be revised upwards.
+"It may increase from the current level of 25 nanomols per litre to a higher level," he says.
+
+Antarctica is a land of extremes and researchers need time to adapt when they get there and when they return
+Flying from Antarctica to Australia will get polar expeditioners home much faster than by ship, but with less time to adjust to everyday life after months of extreme conditions, say researchers.
+Dr Jeff Ayton, chief medical officer of the Australian Antarctic Division in Hobart, says research on Australian soldiers during the Vietnam War suggests that a quick plane trip back could increase the challenge of adjusting to normal life.
+"We know that Antarctica is a stressful environment," says Ayton, who adds that researchers can spend as long as 15 months there.
+"It's characterised by isolation, confinement and extremities of conditions such as cold, darkness and lightness."
+Antarctic life also has its own rhythm which is a fair bit slower than life at home.
+He says that it is normal for returning Antarctic researchers to use their long ship voyage back home to reflect on their time there and what lies ahead of them.
+"A ship voyage normally takes eight to 10 days, if you don't get stuck in the ice for six weeks," says Ayton.
+"We have a psychologist on board to debrief wintering parties," he says. "But that is going to change when we start flying people back in four hours."
+Ayton and researchers from the University of Tasmania are studying the effect of air travel to and from Antarctica as part of a larger study on factors that affect the ability of polar expeditioners to reintegrate after their research trips.
+The three-year study will use the introduction of the air link in 2007/8, approved in last year's budget, to compare the impact of ship and air travel on journeys to and from Antarctica.
+"With the change of logistics from ship to air we need to gain an understanding of whether that will make a difference to the reintegration," says Ayton.
+He says it might be necessary for researchers to see a psychologist before they get on the plane and to get more help once they are at home.
+Resilient personalities?
+Ayton and colleagues are also trying to find out if researchers and their families or significant partners back home have particular psychological 'resilience' characteristics that may make reintegration more successful.
+Such positive personality traits may also help researchers adapt better to the Antarctic environment in the first place.
+Problems adapting to Antarctic life include sleep disturbances, fatigue, lack of motivation as well as depressive or manic tendencies that can lead to conflicts with others in the group, severe problems with work or, in the worst case, suicide. 
+The research by Ayton and colleagues was presented last week at the Scientific Committee on Antarctic Research meeting in Hobart.
+
+Ethiopia, showing the East African rift system in the green area, and the southern end of the Red Sea above it
+The two mighty tectonic plates that form Africa and Arabia are slowly ripping apart, scientists report, potentially shifting the southern end of the Red Sea.
+As a result of this long-term split, the northeast of Ethiopia and Eritrea will be torn from the rest of Africa and may eventually form a huge new sea, they say.
+An international team of geologists reports its study today in the journal Nature.
+Geologists from the UK, US and Ethiopia monitored an earthquake and volcanic eruption in Ethiopia in September 2005.
+The event, in the Afar desert at the southern end of the Red Sea, yielded only small amounts of volcanic material but was hugely significant in terms of geological movement, the geologists report. 
+Using images supplied by the European Space Agency's Envisat satellite and deploying positioning sensors and seismic instruments, the geologists were able to get a rare first-hand look at the event. 
+An 8 metre rupture developed in the ground in the Afar's Dabbahu volcanic massif over a period of just three weeks, and swiftly filled up with molten rock. 
+The movement jostled the jigsaw puzzle that makes up the East African rift system, a Y-shaped fault whose stem comprises the Great Rift Valley and whose two branches comprise the Red Sea and the Gulf of Aden. 
+The East African Rift valley is an active divergent rift valley, one of the few areas on Earth where a continent is being actively separated or rifted by the ongoing forces of plate tectonics.
+The rifting process has been going on for 30 million years and will take millions more to complete. 
+The big rip of 2005 has no precedent in the era of satellite monitoring, which gave the experts this opportunity. 
+They theorise that the well-known segmentation of continental rifts is caused by incursion of magma into the rip, rather than by step-by-step cracking of the surface crust.
+
+Antarctic octopuses, seen here, gave rise to deep sea relatives
+Colder Antarctic waters drove the evolution of deep sea octopuses, suggests new research.
+Australian researcher Dr Jan Strugnell of Queen's University Belfast and the British Antarctic Survey says the formation of ocean currents around the continent millions of years ago provided the right conditions for ocean creatures to evolve.
+She presented her research on octopus evolution last week at the Scientific Committee on Antarctic Research meeting in Hobart.
+Previous research suggests a range of deep sea creatures had their origins in Antarctica, says Strugnell.
+"People have thought for lots of different taxa that maybe this has happened, but no-one's really investigated it properly."
+Strugnell decided to test the theory by studying the evolution of Antarctic and deep sea octopuses.
+She constructed a family tree by comparing the octopus DNA and morphological features, including number of suckers.
+Using fossils to calibrate evolutionary dates, Strugnell says Antarctic octopuses and their relatives evolved around 48 million years ago. 
+And her findings so far suggest deep sea octopuses evolved from Antarctic octopuses some time after 34 million years ago. 
+Strugnell has supported her findings using evidence from a completely different source.
+Continental confirmation
+At various stages in Earth's history, for example 100 and 60 million years ago, global climate change depleted oxygen in the deep sea and all the animals there went extinct.
+Strugnell says the evolution of octopuses in the deep sea would only have been possible once those waters became oxygenated again and Antarctic octopuses were able to colonise them.
+Evidence for the timing of this comes from the movement of the continents, says Strugnell.
+About 34 million years ago, Antarctica separated completely from South America, with the opening up of Drakes Passage.
+This allowed the Antarctic Circumpolar Current to form, which insulated the continent and allowed it to get really cold.
+As cold water is more oxygen rich than warm water, oxygen from Antarctic waters would have been able to then diffuse into the deep seas along with Antarctic octopuses, which then evolved into deep sea octopuses.
+"The opening of the Drakes Passage fits in with evolution of the group," says Strugnell.
+She says it's early days but she is confident about her findings.
+"This is still a work in progress but the evidence is looking good, halfway through my post doc."
+Parts of her research have been published in the journals Molecular Phylogenetics and Evolution and Cladistics.
+
+Our ability to count emerged in stages, linguists say. The latest evolutionary stage allowed us to name lanes on a racetrack 1, 2 and 3 as well as describe which runner came in 1st, 2nd or 3rd
+We can thank our verbal nature, along with our fingers, for the ability to develop complex number systems, a new study suggests.
+The authors theorise that language and maths co-evolved in humans, with language probably emerging just ahead of basic mathematical concepts.
+"I do not think counting words were among the first words spoken by our species, because their application makes use of a fairly sophisticated pattern of linking that occurred ... relatively late in linguistic evolution," says author Dr Heike Wiese, whose study has been accepted for publication in the journal Lingua.
+Wiese, a linguist at the University of Potsdam in Germany, says that our use of counting words, and numbers in general, probably emerged in four stages.
+During the first stage, Wiese believes humans began using visual representations, such as symbols or other markings, to correspond with verbal indications of quantity.
+Among the early evidence for that stage is a 30,000-year-old wolf bone, excavated in the Czech Republic, with notched tallies cut into it.
+The second stage of development, according to the new study, was the evolution of finger counting.
+Our hands are like a built-in abacus: the physiology that allows us to bend fingers individually also allowed the emergence of our ability to count in sequence.
+During the third stage, Wiese thinks emphasis began to be placed on the last word or finger in a counting series.
+This emphasis seems to be inherent to human thinking. For example, when a child who is learning to count is asked how many teddy bears he or she has, the child gives the whole sequence of numbers and then puts emphasis on the last word, as in, "I have one, two, three, four teddy bears."
+Since humans have 10 fingers, that number became a natural transition point during this stage, allowing people to count upward in sets of 10.
+Finally, Wiese believes "a full-blown number concept" emerged in humans with the use of stable word-lists linked to amounts. Counting words and numbers, he says, do not merely refer to numbers. They are the numbers.
+"The idea is that numbers are not some abstract platonic entities that must be grasped by us, but mental tools that we develop ourselves: tools we use to assess properties like cardinality (four buses), rank (the fourth bus), and identity (the number four bus)," he says.
+Counting words and mathematical concepts, therefore, are intertwined with our language skills, and even appear to be dependent upon them. Though the reverse is not the case.
+Some cultures, such as the hunter-gatherer Piraha of the Amazon, have language but do not even possess systems for numbers or counting.
+Professor Terrence Deacon, a linguist at the University of California at Berkeley, agrees with many of the conclusions of Wiese's study.
+"Wiese builds the case for numerical cognition growing out of the symbolic cognition at the base of language - not as a parasitic spin-off, or a mere naming of numerical concepts, but as an ability whose roots extend to the same underlying cognitive operations," he says.
+Several recent studies support the language-maths link.
+In a study published last month in the Proceedings of the National Academy of Sciences, Professor Yiyuan Tang and colleagues found that Chinese and English speakers not only have different ways of representing numbers with language, they also think about numbers with different parts of their brains.
+Yet another study, conducted by Miami-Dade County Public School researchers in Florida, found that bilingual individuals do better at maths than their monolingual peers.
+
+But the impact of racist stereotypes on gamers can be hard to measure, say some critics
+Some popular video games promote racist, negative stereotypes of Asians that would be unacceptable in other forms of media, says a Canadian researcher. 
+Robert Parungao, who studied the topic as part of his honours degree in sociology at the University of British Columbia, looked at four best-selling games: Kung Fu, Warcraft 3, Shadow Warrior and Grand Theft Auto 3.
+Parungao, an avid gamer, says the games feature evil gangsters, all of them non-white, who "function as narrative obstacles to be overcome, mastered or ultimately blown to smithereens by the white hero". 
+He says while blatant racism is not tolerated in mainstream films or television, in video games "it's below the radar". 
+Parungao says his study has had a mixed response. 
+"Some say [racist stereotypes in games] is terrible," he says. "Other people in the games community say, 'Lighten up, it's a game, you don't have to worry about political correctness.'" 
+A fifth-generation Canadian of Chinese and Filipino ancestry, Parungao says that with video game sales at about US$30 billion worldwide, making them more popular than movies, negative stereotypes matter. 
+He admits that not all games, or game publishing companies, promote such stereotypes, but says racism is rife among many of the most popular games, which are designed and published mostly in the US and Japan. 
+"These aren't just kids' toys, these are representative of our society and they teach us," he says. 
+Parungao's study is one of the first to look at racism in video games, says Associate Professor Richard Smith, a specialist in technology and society at Simon Fraser University in Vancouver. 
+"We've heard about sex and violence, but I can't remember hearing about racism in video games," says Smith.
+"The most insidious thing about racism is when people accept it. Studies like this help create consciousness." 
+But Smith cautioned there's no academic consensus that violence and sexism in media affects real-world attitudes, and says the impact of racist images will be hard to measure. 
+"This is new territory," says Smith.
+
+The pharmaceutical industry wants changes in how early-stage clinical trials are run
+Greater caution is needed in early stage tests of novel drugs that stimulate the immune system and only one patient should be given active medicine on the first day, a joint industry taskforce says. 
+Its report was prompted after six men were left seriously ill when a clinical trial in the UK using an experimental drug went badly wrong in March.
+The news triggering widespread public alarm, sending shock waves through the pharmaceuticals industry.
+All six healthy volunteers were given the drug, made by German biotech firm TeGenero AG, at the same time. 
+Professor Colin Dollery, a consultant to GlaxoSmithKline who co-chaired the taskforce, says tens of thousands of initial phase I trials are conducted without incident but the TeGenero episode highlightes the need for extra care with potent biotech drugs.
+This is particularly the case when drugs activate biological processes in the body rather than inhibit them. 
+UK regulators earlier this year concluded that TeGenero's drug TGN 1412 appeared to cause an unprecedented biological reaction in humans by stimulating the immune system, a reaction not seen in animals. 
+"The great majority of drugs are antagonists, in other words, they inhibit processes," Dollery says.
+"Only a minority are agonists, which activate a process. If you have a biological drug that is intended to activate the immune system, which TGN 1412 was, then you have to be very much more careful." 
+Other recommendations from the taskforce, which was set up by the Association of the British Pharmaceutical Industry and the UK's BioIndustry Association, include improvements in ascertaining the right starting dose, 'staggered dosing' as levels are increased and only conducting such trials in hospitals with intensive care facilities.
+Privately owned TeGenero filed for insolvency earlier this month as the publicity surrounding the disastrous phase I study made it impossible for the company to attract investment to keep operating. 
+The trial of TGN 1412, which was designed to treat chronic inflammatory conditions and leukaemia, was conducted on behalf of TeGenero by contract research firm Parexel at Northwick Park Hospital in northwest London. 
+The joint industry taskforce has submitted its conclusions to a separate, government-appointed expert committee on first-in-human clinical studies under Professor Gordon Duff, which is due to issue its report later this week.
+
+A loophole in how people set up VoIP accounts for internet telephony is allowing fraudsters to scam people's bank account details
+Fraudsters have been sending people emails asking them to phone their bank as part of a novel way of stealing account details known as 'vishing', security experts say.
+Internet fraud dubbed 'phishing', where email recipients are directed to a fake website seeking their financial details, has been around for several years.
+But government officials and security experts are warning about vishing, after a recent case of attempted fraud against a Californian bank.
+As opposed to phishing, vishing relies on Voice over Internet Protocol (VoIP) telephony, a way of using the net to make cheap phonecalls.
+The perpetrators take advantage of a quirk in VoIP that allows subscribers to have a telephone number that appears to be based in a city, such as Los Angeles, even though they may be anywhere in the world. 
+"It's a fairly new phenomenon. We're aware of reports they have been occurring," says Lisa Hone, the assistant director of the US Federal Trade Commission's consumer protection bureau.
+The perpetrator or group behind the emails sent to customers of the Santa Barbara Bank and Trust in California last month have yet to be caught, but the bank has alerted its customers to the scam.
+The email sent to the bank's customers preyed on potential victims by requesting they call an apparent local telephone number to clear up an account problem. 
+Any customers who called the telephone number would have heard a recorded message urging them to enter their account number, according to internet security firm Websense. 
+Dan Hubbard, vice president for security research at Websense, says the group alerted the bank, a unit of Pacific Capital Bancorp. 
+Pacific Bancorp could not be reached for comment, but the bank's website has alerted its customers to the scheme. 
+"It's definitely a new trend. It is growing, but it is not nearly as big as the threat of [fake] websites or criminal activity through malicious code; we're talking tens of thousands versus a handful," Hubbard says.
+Online auctions affected too
+But he says similar scams have been attempted against users of the online payments company PayPal, and on the online auction group eBay. 
+UK-based internet security firm Sophos issued an alert earlier this month about a vishing scheme targeting PayPal. 
+"As hackers get smarter we are likely to see them increasingly not only set up fake websites, but 'harvest' messages from corporate switchboard systems to appear even more like the legitimate company," says Graham Cluley, a senior technology consultant at Sophos.
+A VoIP-based fraud can be set up fairly simply, according to security experts. 
+There are relatively few companies that currently offer such internet-based telephone services, and fewer checks are generally required compared to opening an account with a traditional telephone company. 
+False voicemail
+Essentially, a fraudster signs up for a VoIP account, sets up a voicemail recorded message system, mimicking that of an actual bank or other company, then mass emails consumers urging them to call the false number. 
+Hone says the scam, as in the California case, can appear legitimate to unsuspecting consumers because VoIP accounts can be set up with local telephone codes of a user's choice in a variety of cities or states. 
+"One VoIP account can have numbers all over the country, the code makes it look more real, and set-up is easy," Hone says.
+
+You can lose weight on a high carbohydrate diet but not all carbs are equal
+There's no difference between a low GI diet and a high protein diet when it comes to losing weight, an Australian study has shown.
+The study, published in the Archives of Internal Medicine today, is the first to directly compare high protein diets and those based on foods with a low glycaemic index or GI.
+But the research shows low GI diets are better than high protein diets in reducing 'bad' or LDL (low density lipoprotein) cholesterol associated with cardiovascular disease.
+"In terms of weight and fat loss [a low GI diet] and [a high protein diet] were exactly the same, there was no difference in terms of weight or fat loss between those two studies," reports lead author Joanna McMillan-Price from the University of Sydney's human nutrition unit.
+Professor Jennie Brand-Miller, who co-authored The Low GI Diet Revolution with McMillan, was also involved in the research.
+Turning carbohydrates into glucose
+Low GI diets were originally used to control diabetes because of their ability to prevent dramatic fluctuations in insulin levels. 
+The body takes longer to convert low GI foods to glucose, which means glucose is released into the bloodstream more slowly, preventing spikes in insulin levels that can leave you feeling hungry and prevent the breakdown of fat.
+More recently, low GI diets gained popularity among dieters, with celebrities like Kylie Minogue reported to favour low GI foods.
+Highly processed, low fibre foods like white bread and soft drinks have a high GI while foods like dark whole grain breads, fruit and legumes have a low GI.
+Fat or cholesterol?
+The researchers put 129 overweight men and women on one of four diets for 12 weeks.
+Of those four, one was low GI and another was high in protein.
+At the end of the study both the low GI and high protein group had lost the same amount of weight.
+A third diet, which was heavy on carbohydrates with a high GI, achieved the slowest rate of weight loss.
+While LDL cholesterol "declined significantly" in the low GI group, it increased among the people on the high protein diet.
+McMillan-Price says the research not only suggests that a low GI diet is the best eating choice, but it also vindicates the consumption of the right kind of carbohydrates for those wanting to lose weight.
+"For so long now we've had hype that it's all about high protein and we must reduce our carbs," McMillan-Price says.
+"It's been a confusing message and it's quite reassuring to hear that yes, I can eat a high carb diet as long as I'm smart about the carbs I choose."
+High protein or low GI?
+Dr Peter Clifton, research director at CSIRO Human Nutrition, says the study shows that both high protein and low GI diets can reduce weight.
+"Certainly [the study] doesn't provide any evidence [low GI diets] are the best, they're an equivalent," says Clifton, who co-authored the bestselling CSIRO high-protein Total Wellbeing diet.
+Clifton says high protein diets also provide more zinc and iron that a high carb diets, and are more likely to leave you feeling fuller for longer.
+"[But the study shows that] if you don't like eating large amounts of protein then choosing low GI products is probably not bad alternative," he says.
+McMillan-Price's study received funding from Meat and Livestock Australia.
+
+Can modern technology help solve the secrets of Egypt's ancient pyramids?
+Archaeologists who measured the Egyptian pyramids at Giza more than 100 years ago were surprisingly accurate, a review of historical surveys has shown.
+The paper, posted online by Australia's Queensland University of Technology, reviews the major surveying projects of the pyramids Cheops, Chephren and Mycerinus, built around 2600 BC south of what's now Cairo.
+"They weren't that far out; their surveys were quite diligent and systematic and we're getting fairly good agreement using modern technology," says the paper's co-author Robert Webb, a lecturer in surveying in the school of urban development.
+But Webb says laser scanning, computer modelling and other modern technology hasn't brought us any closer to answering one of the most intriguing questions about the pyramids.
+This is whether their position and measurements deliberately reflect the alignment of the planets and stars.
+"[Earlier surveys have found] a very close relationship to the planet alignments and what we can measure on the ground," he says.
+"But it's more of a theory and some people have also found while the similarities appear on the surface to be quite close, it's just really one of those mathematical flukes."
+According to the review, the two major historical surveys of the pyramids were made in 1880 and 1925 using wire, steel tape and mahogany rods.
+The most recent attempts to map the pyramids have used laser scanning, GPS, satellite imaging, digital technology and computer visualisation.
+Questions of alignment
+The 1880-1882 survey by Sir William Flinders Petrie concluded that there was no spatial connection between the distances and directions of the pyramids and anything else.
+But theories since then have suggested the spatial relationship of the pyramids reflected the alignment of Orion's Belt and the orbital path of Mercury, Mars and Venus. 
+Other theories have included suggestions that the perimeter of the Great Pyramid, or Cheops, of 36,525 pyramid inches is equal to the number of days in 100 years and the number of books of ancient wisdom credited to the Egyptian god Thoth.
+A pyramid inch, the basic unit used in measuring pyramids, is just a fraction over one inch.
+Webb says initiatives like the University of Chicago's Giza Plateau mapping project have revealed peculiar alignments inside the pyramids that could possibly shed more light on alignment theories.
+"Computer visualisation of the insides of the pyramids and their chambers has the potential to really reveal some relationships we may not know about as yet," he says.
+But he says that mystery still surrounds the pyramids.
+"In reality we will never know what inspired the ancient Egyptians to position the pyramids as they did," the paper concludes.
+
+Exposure to cosmic radiation and microgravity is expected to generate super-seeds and super-plants
+China plans to blast seeds into space in a novel way of boosting the nation's food production, reports say.
+Scientists hope that exposure to cosmic radiation and microgravity will cause genetic mutations in the seeds that will improve crop yield back on Earth.
+Some 2000 seeds will go into orbit as part of a two-week mission aboard a recoverable satellite, Shijian-8, the China Daily newspaper reports.
+This is set to be launched by a Long March 2C rocket in early September.
+The 'seed satellite' will enable scientists to try to cultivate high-yield and high-quality plants, Sun Laiyan, head of the China National Space Administration, told the paper.
+"Exposed to special environments such as cosmic radiation and microgravity, some seeds will mutate to such an extent that they may produce much higher yields and improved quality," the paper says.
+Nine categories of seeds, including grains, cash crops and forage plants will be aboard the satellite, it says. 
+China has been experimenting with space-bred seeds for years, with rice and wheat exposed to the universe resulting in increased yields, the paper says. 
+Space-bred tomato and green pepper seeds have resulted in harvests 10-20% larger than ordinary seeds, while vegetables grown from space-bred seeds have a higher vitamin content, it adds. 
+However the satellite to be launched in September will be the first dedicated specifically for seeds. 
+China's space seed experiments come as the nation seeks ways to feed its 1.3 billion people amid a rapid decline in farming land due to swift industrialisation. 
+The nation has pursued some forms of genetically modified crops, with GMO tomatoes, soy beans and corn already in production.
+China is also mulling plans to approve the production of genetically modified rice. 
+'Scotty' revisits final frontier
+In other space news, the remains of actor James Doohan, who played Scotty on Star Trek, will be blasted into space in October, the company organising the flight says.
+The actor who inspired the catchphrase "Beam me up, Scotty", even though it was never actually uttered on the show, died a year ago at the age of 85. 
+Houston-based company Space Services originally planned to blast Doohan's remains into space last year but the flight was delayed to allow more tests on the rocket. 
+The company previously blasted the remains of Star Trek creator Gene Roddenberry into space in 1997.
+
+An artist's impression of a spacecraft exploring the icy Kuiper belt
+Researchers say they have found the first evidence that the frozen outer reaches of our solar system could be littered with many more objects than we think.
+Astronomers have been trying to get a picture of the region, known as the Kuiper belt, because it is believed to contain debris from the birth of our solar system and so could tell us how planetary systems form.
+About 1000 large bodies, including Pluto and the recently discovered Xena, have been located in the Kuiper belt so far.
+But smaller objects have evaded detection as they are about 15 billion kilometres from the Sun, making it impossible to see them even with a powerful instrument like the Hubble Space Telescope.
+Now an Australian team from the University of New South Wales (UNSW) and the Anglo-Australian Observatory (AAO) has used optical fibre technology to detect signs of smaller Kuiper belt objects for the first time.
+The wink of a star
+They did this by observing split-second 'winking', or darkening, of stars which suggests a Kuiper belt object is passing in front, or occulting the star.
+UNSW student George Georgevits presented his research at a recent workshop attended by international Kuiper belt experts in Italy.
+His colleague Associate Professor Michael Ashley of UNSW says the observations offer the first evidence the Kuiper belt contains many more relics of the infant solar system than estimated.
+"Basically our observation showed that that are many more, maybe five or 10 times as many, of the smaller objects than theory predicted," he says.
+Ashley says Georgevits and fellow researcher Dr Will Saunders of the AAO found evidence of many objects ranging in size from 300 metres to one kilometre across using a 6DF instrument on the UK Schmidt telescope at Siding Spring.
+The 6DF, which uses fibre optics, monitored 100 stars simultaneously over two weeks, the equivalent of 7000 star hours, or watching a single star every night for 3 years.
+"We've got 100 fibres, each one of which is positioned on a star and then we feed the fibres into a high speed camera," he says.
+A fraction of what's out there
+Ashley says it's been suggested there are around 100 billion objects in the belt, but the latest observations suggest this could represent only a fraction of what's there.
+"We saw at least 100 very definite [occultations] and as ... you look for smaller, less significant events we could have seen up to 1000," he says.
+The Kuiper belt community has greeted the news with some scepticsm. Some critics say that the apparent dimming of the stars may be due to effects in the Earth's atmosphere.
+Ashley says the scientists took pains to rule out other possible causes for dips in stars, including moths in the telescope.
+
+But this research won't turn a pot belly into a flat stomach
+Stem cells taken from human fat can be transformed into smooth muscle cells, offering a way to treat diseases of the heart, gut and bladder, US researchers report.
+While the experiment does not quite offer a way to turn a pot belly into a flat stomach, the researchers say the transformed cells contracted and relaxed just like smooth muscle cells.
+These cells help the heart beat and blood flow, push food through the digestive system and make bladders fill and empty, the researchers report. 
+Their study, published in the Proceedings of the National Academy of Sciences today, is the latest to show that fat can be a rich source of the body's master cells.
+"Fat tissue may prove a reliable source of smooth muscle cells that we can use to regenerate and repair damaged organs," says Dr Larissa Rodriguez, an assistant professor in the urology department at the University of California Los Angeles medical school.
+Rodriguez and colleagues incubated adipose-derived stem cells in a nourishing mixture of growth factors, human proteins that encouraged the cells to become smooth muscle cells. 
+The researchers say scientists have been looking for sources of smooth muscle for organ repair and treating heart disease, gastrointestinal diseases and bladder dysfunction. 
+"A major obstacle for such an approach has been finding a reliable source of healthy smooth muscle cells that can be safely harvested and that require minimal manipulation," they write. 
+Clean, healthy fat
+One approach has been to take a patient's own cells from an organ. But studies have shown that stem cells taken from a diseased organ are also damaged and do not work well when scientists try to grow them in the lab for a transplant. 
+Transplants grown from a patient's own fat could be used with no need for anti-rejection drugs, Rodriguez says.
+Smooth muscle cells have been produced from stem cells found in the brain and bone marrow, but acquiring stem cells from fat is much easier, she adds. 
+The stem cells found in fat are known as multipotent stem cells. They can produce a variety of cell and tissue types, but are not as flexible as embryonic stem cells. 
+Others also looking at fat
+Many groups have been looking to fat as a source of stem cells. In April, Cytori Therapeutics said it was starting a clinical trial to test whether stem cells derived from fat can be used to regenerate breast tissue. 
+Other researchers have been trying to get stem cells from liposuction specimens. 
+In a second study published in the same journal, UK researchers say they found one important protein that keeps stem cells in a quiescent and non-dividing stage. 
+Dr Fiona Watt of Cancer Research UK and colleagues studied stem cells from human skin and found a protein known as Lrig1 kept the skin cells from proliferating.
+When Lrig1 production was silenced, the stem cells began growing and dividing.
+The finding may not only offer important information to stem cell researchers, but may also offer insights into cancer, Watt's team says.
+In cancer, cells ignore the normal signals from the body and proliferate uncontrollably. 
+The protein is also involved in psoriasis.
+
+The mud in this cave is formed from 340 million year-old clay
+The Jenolan caves west of Sydney date back some 340 million years, making them the oldest known open caves in the world, Australian geologists say.
+Dr Armstrong Osborne from the University of Sydney and colleagues used clay dating methods to show the caves have been open since the Carboniferous period.
+Their results are published in a recent issue of the Australian Journal of Earth Sciences.
+"We've shown that these caves are hundreds of millions of years older than any reported date for an open cave anywhere in the world," Osborne says.
+The oldest previous dating for an open cave was around 90 million years, he adds.
+"Even in geological terms, 340 million years is a very long time. To put it into context, the Blue Mountains began to form 100 million years ago; dinosaurs became extinct 65 million years ago, and Tasmania was joined to the mainland as recently as 10,000 years ago."
+Until recently, scientists had thought the caves were relatively young. But Osborne thought the underground system might be older.
+"It always struck me as weird that in a country where everything is so old, that the caves should be young," he says.
+The challenge was finding something inside the caves that could be accurately dated.
+So when a chance meeting revealed that Dr Horst Zwingmann from CSIRO Petroleum Resources had a technique that could be used to date the clay inside the caves, they set about finding their real age.
+Borrowing from the oil industry
+The researchers used dating methods developed to help oil exploration companies find oil deposits.
+The techniques are based on potassium-argon dating, which can calculate the age of minerals by measuring levels of decay caused by radioactive potassium.
+The results were a complete surprise. 
+"No one imagined that they would be more than 300 million years old. This was totally off the planet," Osborne says.
+"We were able to provide evidence that the clays did form in-situ in the caves and that the sections regularly visited by tourists actually formed in the Carboniferous," Zwingmann says.
+The clay now forms much of the mud in the popular Temple of Baal and Orient caves.
+The discovery opens the possibility that there could be evidence of other ancient geological events in the caves that scientists haven't looked for yet.
+For example, the researchers think the clay in the cave was formed when volcanic ash entered.
+
+Irradiation could be a way of inactivating bacteria used to make vaccines
+Vaccines made with bacteria killed by gamma rays may be more effective than those made using standard heat or chemical inactivation, US government researchers say. 
+Such vaccines do not have to be kept cold, the team at the University of California, San Diego, School of Medicine report in the journal Immunity.
+Dr Sandip Datta and colleagues made a vaccine from Listeria monocytogenes bacteria, a common cause of food poisoning. 
+The listeria were killed with gamma rays and the vaccine protected mice infected with live listeria, unlike vaccines made with heat-killed bacteria. 
+"Although completely inactivated by the radiation, and thus unable to cause illness, irradiated bacterial pathogens evidently retain characteristics that prompt the immune system to mount a full-fledged defence," Datta says.
+Vaccines can be made in three ways: using an attenuated, or weakened, form of live bacteria or virus, using a killed microbe, or using pieces of DNA from a bacteria or virus.
+Most attenuated vaccines must be kept cold, but the researchers found that mice could be protected by vaccination with irradiated listeria that had been freeze-dried into a powder. 
+This might mean that such vaccines could be used in hot places without electricity, the researchers say. 
+Vaccines often protect mice but not people so the idea must be tested more, the researchers note.
+Dr Elias Zerhouni, head of the National Institutes of Health, which funded the study, says:
+"This advance is potentially of great importance in meeting the challenge of creating vaccines that are safe, effective and simple to manufacture and transport." 
+Gamma rays are also used to sterilise medical equipment and, in some countries, to preserve food.
+
+Scientists are still working out how to measure objects accurately at the nanoscale
+Some of the smallest things in the world are so small that not even the scientists making them know how tiny they are.
+The scientists can't seem to agree how to accurately measure these nanotechnologies, which commentators say is an important step in making sure they work properly and their risk is minimised.
+Accurately measuring the size of nanomaterials is crucial because nanotechnology relies on novel properties that emerge at the nanoscale.
+And it's important in safety assessment because particles under a particular size may be dangerous to human or environmental health.
+Dr John Miles, manager of nanometrology at Australia's National Measurement Institute in Melbourne, is one of the scientists trying to work out how to accurately measure nanotechnology, such as nanoparticles.
+"Measurement at this level is an extremely difficult thing to do because it's so much smaller than the things we normally deal with, getting down to almost atomic dimensions," says Miles, who is on an international committee responsible for setting measurement standards for nanotechnologies.
+But if you have an oval-shaped nanoparticle, for example, do you measure its width or length? And how do you measure a nanoparticle with a rough surface?
+The shape and surface smoothness of a particle become important when measuring at the nanoscale, Miles says, because the particles themselves are about the same size as things like surface irregularities.
+Depends on the lab
+Miles says studies have shown that different labs, even using the same measuring technique, have delivered very different measurements of nanoparticles.
+For example, nanopolystyrene spheres, which suppliers say are 80 nanometres in size, have been measured as being 15 nanometres smaller or bigger depending on who is measuring them, he says.
+And measurements of silver nanoparticles have been 10 nanometres smaller or bigger, depending on the lab, says Miles. 
+Nanometrologists don't yet know whether suppliers are producing unreliably-sized particles or whether those measuring them are getting it wrong.
+"There is a need worldwide for a quick, convenient way of measuring nanoparticle sizes," says Miles. "If someone could come up with a way of doing that they would make a lot of money."
+Scattering light
+The most practical machine being developed for the job uses what is called dynamic light scattering (DLS). 
+This technique shines laser light onto a solution of nanoparticles and measures their Brownian motion, the jiggling that happens when nanosized particles are bombarded by other molecules.
+The smaller the particles, the more they jiggle, and the trick is to accurately calibrate their jiggling with standard metric measurements.
+Miles says his institute is working on a DLS device to calibrate nanopowders as reference standards for industry. But he says the instrument is three or four years away.
+Nanorulers
+An alternative in the meantime is to use an electron microscope to image the particles and then a 'nanoruler' to measure them.
+The problem is that this method is time-consuming because it only measures relatively few particles at a time, whereas DLS can quickly measure an entire batch of particles in one go.
+There is currently no regulatory requirement for the billion-dollar nanotechnology industry to use reliable measuring devices.
+
+Drizzle one day, flash floods the next
+It's raining methane on Saturn's giant moon Titan, scientists say.
+It ranges from a persistent drizzle that keeps the surface of Saturn's largest moon damp to fierce storms that could produce huge droplets.
+"We have found the first evidence of drizzly rain on a remote planet, in this case Titan, which consists of liquid methane and a little bit of nitrogen," says Dr Tetsuya Tokano of Germany's University of Cologne.
+Tokano and his colleagues publish their findings today in the journal Nature.
+The researchers used data from the NASA/European Space Agency Cassini-Huygens mission to measure the atmospheric chemical composition, temperature and pressure on Titan. 
+The Cassini craft was launched in 1997 and reached Saturn in 2004 after cruising past Venus and Jupiter. 
+Information from the probe showed Titan, which is larger than the planet Mercury, is cold and windy with a dense atmosphere of methane and nitrogen.
+According to the team's findings, much of the surface of Titan could experience a drizzle for the next few years. 
+Fierce storms too
+In a separate report in the journal researchers from Spain modelled Titan's atmosphere.
+They predicted clouds over the south pole would produce fierce storms that would pound the surface and could help explain the formation of its river valleys. 
+Dr Ricardo Hueso and Dr Agustin Sanchez-Lavega of the University of Pais Vasco in Bilbao say under the right conditions the storms could produce methane raindrops up to 5 millimetres across that would pound the surface similar to flash floods seen on Earth.
+Tokano says although the Spanish researchers reached a different conclusion he believes both types of rainfall could occur on Titan depending on the conditions.
+"We do not rule out the presence of such heavy rainstorms because such clouds have been observed near the south pole," he adds.
+
+Adult (top) and juvenile (bottom) Umoonasaurus, one of two new species of ancient marine reptile
+Scientists have identified two new species of ancient marine reptile that swam in an Australian outback sea 115 million years ago.
+The reptiles, named Umoonasaurus and Opallionectes, belonged to the plesiosaurs group which included a predator like a killer whale from the Jurassic period, says palaeontologist Dr Benjamin Kear from the University of Adelaide.
+Kear, whose team studied 30 opalised fossils mainly from around the outback mining town of Coober Pedy in South Australia, publish their research in the latest issue of the journal Palaeontology and online in the journal Biology Letters.
+Kear says the long-necked marine reptiles swam in the shallow water of an inland sea that once existed in central Australia.
+Freezing polar water covered large parts of Australia 115 million years ago when the island continent was much closer to Antarctica. 
+The Umoonasaurus was about 2.4 metres long and had three crest-like ridges on its skull.
+"Imagine a compact body with four flippers, a reasonably long neck, small head and short tail, much like a reptilian seal," Kear says. 
+The team named the reptile after the Aboriginal name for Coober Pedy, Umoona.
+The Opallionectes was 6 metres long, with masses of needle teeth used to trap small fish and squid.
+Its name means 'the opal swimmer from Andamooka', the scientists say.
+Kear says most of the fossils found were of juvenile creatures, leading the scientists to believe they had discovered a seasonal breeding ground for the ancient reptiles.
+
+Light-detecting fibres could one-day be used to capture images from space
+Move over digital cameras. Imaging with special light-detecting fibres may be on its way.
+Researchers from the Massachusetts Institute of Technology (MIT) have developed a crisscrossing web of transparent fibres that senses the direction, intensity and phase of light in 3D.
+It does this without lenses, filters or detector arrays typically used for the task.
+The lightweight fibres could be used to make space telescopes that unfurl sail-like imagers, say the scientists.
+Alternatively, interactive computer screens made with the fibres could respond to light instead of mouse clicks.
+And fibres in electronic clothing could one-day sense the environment better than the wearer.
+"We have shown already that these very simple fibre arrays can extract images without a lens," says Yoel Fink, an associate professor of materials science at MIT.
+Fink, with postdoctoral associate Ayman Abouraddy and colleagues, publish the results in the latest issue of the journal Nature Materials.
+In conventional imaging systems, the lens is a crucial component, as it focuses the light onto the detector surface, whether that is a light-sensitive film or computer chip.
+But in Fink's system, a software algorithm does the work of the lens after light hits the photo-detecting fibres.
+"It's a completely new way of doing things," says Eli Yablonovitch, professor of electrical engineering at University of California, Los Angeles.
+Fibres have three elements
+The fibres are 1 millimetre in diameter and have three elements: a semiconducting core flanked by metal conductors, all encircled in an insulating shell of a polymer.
+Weaving the fibres together produces a screen-like product with unique coordinates for each location where two fibres intersect.
+With this method, scientists can pinpoint where on the grid light is shining.
+Placing one screen in front of another, or forming one screen into a sphere as the team did in laboratory tests, provides even more detail.
+Light passes through a coordinate on the facing screen and through another coordinate behind. So the scientists determine where the light came from by drawing an imaginary line through the two coordinates.
+At the same time, the fibre is collecting information about the light, including its intensity and the frequency of the light waves. 
+A software algorithm then calculates how the light would change if it passed through a lens and uses the answer to generate a picture of the light's source.
+Light from all directions
+Whereas conventional imaging systems have a limited field of view, Fink's system can sense light coming from all directions.
+"The beauty of this is that they are able to make this three-dimensional detection and to do so with an object that is essentially transparent," says Malvin Teisch, professor of physics and electrical and computing engineering at Boston University.
+Fink's team is working on fibres that can sense a wider range of light wavelengths, to produce colour images, as well as ones that can read heat and sound.
+
+Sensitive tastebuds may explain why your kids won't eat broccoli, carrots or cucumbers
+Picky kids who won't eat vegetables may be particularly sensitive to bitter flavours, a new study shows.
+These preschoolers turn up their noses at not only bitter vegetables, like broccoli and olives, but sometimes also sweeter vegies like carrots and red peppers. 
+The findings suggest that innately sensitive tastebuds help explain why some children are so staunchly opposed to vegetables, the study authors report in the latest issue of the American Journal of Clinical Nutrition.
+In recent years, scientists have identified a gene, dubbed TAS2R38, that controls a receptor for bitter flavour. 
+A study published last year found that children with certain variations of that gene are particularly sensitive tasters, able to detect a very small amount of a bitter-tasting compound in water. 
+The 65 preschoolers in the current study were tested the same way.
+A total of 37% said the water tasted "yucky" or bad, while the rest couldn't taste anything and were considered "nontasters". 
+When the children were given free range to snack on bitter-tasting vegetables (broccoli, olives and cucumbers) and sweeter ones (carrots and red peppers), the sensitive kids ate significantly fewer bitter vegetables.
+And while only 8% of nontaster children refused all of the vegetables, 32% of the sensitive tasters did so.
+At the dinner table
+So what should parents make of all this? According to the researchers, parents of fussy eaters should recognise that their children may not be having the same taste experience that they are. 
+"Parents should try not to project their own food preferences onto their children," says study co-author Dr Beverly Tepper, a professor of food science at Rutgers University.
+A nontaster parent who loves broccoli, for instance, may have a more bitter-sensitive child who simply doesn't enjoy the greens in the same way, she says. 
+But that doesn't mean that bitter-sensitive kids are destined to shun vegetables their whole lives, a potential comfort to parents who regularly engage in mealtime struggles. 
+"We do change our food preferences as we grow and learn," Tepper says, noting that the "impact of genetics isn't set in stone". 
+Whether there's a more immediate fix to the bitter-sensitivity issue is unclear.
+A tasty sauce might make vegetables more palatable to a sensitive child, but dousing veggies with toppings may not be the most nutritionally sound choice, Tepper says. 
+Serving vegetables cooked rather than raw might help, she says, as cooking takes some of the bite out.
+
+One day we may be able to make stronger nylon by starting at the nanoscale
+A US scientist has made the world's smallest fragment of nylon and hopes to make more by harnessing the self-assembling properties of DNA.
+Professor Nadrian Seeman of New York University says the long-term plan is to make ultra strong nylon.
+He gave a paper on his work at the recent International Conference on Nanoscience and Nanotechnology in Brisbane.
+"The same properties of DNA that make it such a wonderful genetic material can be utilised in other ways," says Seeman, a pioneer of what is called structural DNA nanotechnology.
+In nature, DNA's bases enable it to pair up with and attach to another strand of DNA to form a linear double helix.
+Seeman is exploiting this ability of DNA to self-assemble to make his nano-nylon.
+But he is using synthetic DNA that can form branches rather than linear lines.
+"You can make lattices, you can make networks, you can make objects, you can make all sorts of things with branched DNA whereas with linear DNA you're just making a long line," he says.
+Seeman has been working on a synthetic version of a related molecule, RNA, which also self-assembles.
+So far, he's attached chemical groups used to make nylon to fragments of synthetic RNA to make the equivalent of a single molecule of nylon.
+"That's about the shortest piece of nylon you can make," he says.
+He is now working on making larger pieces of nylon using DNA. The plan is to knit the nano-nylon into a form of molecular chain mail, which would make a much tougher and stronger fabric than currently exists.
+But, says Seeman, this is a long-term project.
+"This is very hard chemistry," he says, revealing that it took seven years to work out how to attach the nylon components to DNA.
+Bottom-up assembly
+Nearly 20 years ago scientists amazed the world by writing the world's tiniest corporate logo in atoms.
+The tiny IBM logo was made using a large machine that laboriously placed each atom in place. 
+Seeman's research is part of a different approach to assembling things at the atomic or molecular level. 
+"We're talking about making things from the bottom up," he says, "unit by unit".
+The approach involves mixing synthetic DNA molecules in a solution to assemble vast amounts of desired molecular structures.
+Seeman says molecular self-assembly can also be used to organise nanoelectronics, an idea he first raised in 1987.
+This would involve attaching molecules that conduct electricity, such as carbon nanotubes, to DNA.
+So far, Seeman has demonstrated the concept by attaching gold nanoparticles to DNA.
+He says his work could also be used as a tool in the imaging of biological molecules, including drug receptors, which in turn will be useful in drug design.
+Seeman is funded by the National Institutes of Health, the National Science Foundation, Nanoscience Technologies Incorporated and the US military.
+
+The vehicle combines the best of a helicopter and fixed wing aircraft, say researchers. It stands 1.5 metres high and has a wingspan of 2.4 metres
+A new unmanned aerial vehicle (UAV) that takes off vertically like a helicopter and then flips over to fly forward like a conventional plane is being developed by Australian researchers.
+The T-Wing could provide cheaper and more efficient surveillance and reconnaissance, says Dr Hugh Stone of the University of Sydney whose team has been carrying out test flights.
+"It can take off and land like a helicopter," says Stone, an aeronautical engineer who began the research as a PhD project. "It doesn't need a runway." 
+While helicopters can take off and land vertically and can hover, they are not as efficient at forward flight as conventional aircraft, which means they don't tend to fly as fast or as far.
+This is why 'convertiplanes' were developed, aerial vehicles that convert from helicopter to plane mode.
+Other UAV convertiplanes use helicopter type propeller blades and more complex and expensive technology to control the movement of the vehicle, says Stone.
+But the T-Wing uses fixed propellers, like a standard aircraft.
+Moving flaps that sit in the airstream behind the propellers are responsible for changing the direction of the aircraft and allow it to hover.
+These flaps are controlled by an onboard computer system that detects and changes the plane's location and orientation.
+"We can basically tell it a set of points in space and we upload those to the vehicle and then it will fly through those points," says Stone. "It doesn't need any intervention from us."
+Unstable
+Like other similar vehicles the T-Wing is quite unstable and the flaps have to move 50 times a second to keep the vehicle hovering.
+While it is not possible to fly the aircraft by radio control from the ground, it is possible to communicate with the onboard computer system in an emergency.
+"We can intervene if something starts to go wrong," says Stone.
+So far the team has successfully tested a prototype that is 1.5 metres high with a 2.4-metre wingspan and weighs 30 kilograms.
+In the tests, the aircraft flew autonomously, except while landing when it had some assistance from radio control on the ground. The team plan to do further testing in December.
+Surveillance
+Stone says UAVs are generally equipped with cameras and used for surveillance and reconnaissance.
+The research has been funded by the Australian Research Council, the University of Sydney and a US$30,000 grant (A$39,000) from the US Air Force.
+Stone says his team is working with Australian technology company Sonacom to develop a commercial version of the aircraft for surveillance applications.
+
+New research into how HIV replicates in the gut may help to explain why antiviral therapy doesn't work for all patients
+HIV replicates in the lining of the gut and does much of its damage to the immune system there, researchers say.
+Professor Satya Dandekar, at the University of California Davis Health System, and colleagues report their findings in the latest issue of the Journal of Virology.
+Dandekar says the study is the first to explain why the drug cocktails that HIV patients take so often fail to work completely. 
+"The real battle between the virus and exposed individuals is happening in the gut immediately after viral infection," she says. 
+"We need to be focusing our efforts on improving treatment of gut mucosa, where massive destruction of immune cells is occurring.
+"Gut-associated lymphoid tissue accounts for 70% of the body's immune system. Restoring its function is crucial to ridding the body of the virus."
+HIV cannot be cured but the drugs, known as highly active antiretroviral therapy, or HAART, can keep the virus under control. 
+At first, doctors had hoped that years of treatment might eventually eradicate the virus. 
+But, 25 years on from the advent of AIDS, it is clear that cannot happen. That is because the virus can hide out quietly in reservoirs, which include certain immune cells. 
+The gut is clearly important too, Dandekar's team says. 
+"We found a substantial delay in the time that it takes to restore the gut mucosal immune system in those with chronic infections," Dandekar says.
+"In these patients the gut is acting as a viral reservoir that keeps us from ridding patients of the virus." 
+The mucosa are the wet tissues that line the nose and throat, the genitals and the inside of the gut. HIV often infects people via the mucosa.
+Long-term survivors
+Dandekar's team has been studying HIV-infected patients who, even without treatment, have survived more than 10 years with healthy immune systems, including the T-cells that the virus attacks. 
+"We looked at their gut lymphoid tissue and did not see loss of T-cells there. This correlated with better clinical outcomes," Dandekar says. 
+So they started the current study, following 10 patients being treated with HAART, taking blood and gut samples before and after three years of treatment. 
+They found evidence of inflammation, which disrupts tissue function, promotes cell death and upsets the normal balance of gut bacteria. 
+Dandekar say these findings suggest anti-inflammatory drugs may help HAART to work better.
+
+The Australian velvet worm Euperipatoides rowelli is a living fossil that has been puzzling researchers for years
+The soft and elusive velvet worm might look like a pretty caterpillar. But its brain is strikingly similar to that of a spider, new international research shows.
+The architecture of the worm's brain has more in common with a spider's brain than with the brains of other arthropods, researchers report in the journal Proceedings of the Royal Society B: Biological Sciences.
+Velvet worms have a body formation between that of a worm and an insect and for many years scientists believed they were the 'missing link' between the two.
+This view was supported not only by the way they look, but also by the fact that they date back 540 million years.
+Researchers including Associate Professor David Rowell from the Australian National University in Canberra were interested in finding out whether this was true.
+They found out that the worms are not a sister group of the arthropods, but lie within the arthropods and share a common ancestry.
+The team catalogued aspects of the microanatomy of various arthropod brains and then loaded the information into a computer program designed to sort out molecular lineages and create a 'family tree'.
+"We found the [worms] did actually fall within the arthropods and are very similar to the chelicerates [spiders and scorpions]. The brains of the velvet worms looked strikingly like spider brains," Rowell says.
+"That's interesting for a number of reasons. Firstly because it's not something we've seen before, and secondly because the worms don't carry many of the body characteristics of the chelicerates and yet their brain structure suggests that they are [similar].
+"We can only assume that [over time] they lost a lot of the characters that identified them as chelicerates."
+Velvet worms, or onychophorans, are extremely rare and are only found along the east coast of Australia, Tasmania, New Zealand, South Africa, South America and along the tropics. 
+Contrary to the way they look, they are vicious carnivores that "eat almost anything that moves", Rowell says. 
+They trap their prey by firing a sticky goo over them.
+
+Are we literally flushing away a potential source of extra drinking water by saying 'no' to recycled sewage?
+Australians will one-day come to terms with the need to drink recycled sewage, despite the recent decision of a Queensland town to veto it, experts say.
+The residents of Toowoomba voted in a weekend referendum against the plan to introduce treated sewage into the local water supply.
+But advocates of recycling say rather than killing off the debate, the 'no' vote marks the opening shot in a new debate.
+Professor Nick Ashbolt, head of civil and environmental engineering at the University of New South Wales (UNSW), says recycling sewage is inevitable given Australia's swelling population and looming water shortage.
+"Basically it's essential," he says.
+"We don't have enough water to go around. If you do the growth predictions of major cities, based on current water usage we'd be sucking our rivers dry and still not supplying enough water."
+Associate Professor Greg Leslie, of the UNESCO Centre for Membrane Science and Technology at UNSW, says if Toowoomba residents had been given more information before the referendum they would have voted differently.
+"What we need to do is make sure that when the next vote comes along there's a more informed debate," he says.
+"The next town that makes this decision would probably do it in a more enlightened environment rather than one that was dominated by [the belief] you'll be drinking turds from your toilet."
+The best drinking water in Australia
+Leslie says the proposed treatment would have given Toowoomba residents the cleanest drinking water in the country.
+"The water that would come out of that plant at Toowoomba, had it been built, would have been the best quality water in Australia," he says.
+This is because it would have been more highly treated than normal drinking water.
+Under the Toowoomba plan sewage would have passed through two membrane barriers including a 0.2 micron microfilter and a reverse osmosis membrane.
+Reverse osmosis, which is also used in desalination, reduces the total organic carbon content from 8 milligrams per litre to 0.1 milligrams per litre, he says.
+After passing through the filters the water would then have been treated with a combination of UV light and peroxide to "polish the water at a molecular level".
+Drinking water generally only passes through a sand or carbon filter and isn't subject to reverse osmosis, he says.
+While Toowoomba has been portrayed as a national landmark, Leslie says residents of one New South Wales town have been drinking treated sewage since 1985.
+He says people in Richmond, west of Sydney, drink treated sewage because the effluent is released into the Hawkesbury River near the local water treatment plant, which also draws its water from the river.
+"The level of treatment that [the plant] provides to the water before it puts it into the river is much less than they were proposing at Toowoomba," he says.
+Ashbolt says up to 70% of the water that goes into the treatment plant is tertiary treated effluent, or effluent that been treated to the standard level to allow it to be released into the environment.
+The Toowoomba plan would have involved 25% of its water coming from highly treated effluent.
+"We're already doing in Sydney what they said they wouldn't do in Toowoomba," he says.
+But Professor Don Bursill, retired former chief executive officer of the Cooperative Research Centre for Water Quality and Treatment, says there will always be some risks when sewage is turned into drinking water.
+He says the chance of some pathogens and chemicals slipping through even the most sophisticated filtering systems can't be ruled out.
+Bursill also says water workers would need to be specially trained and the regulatory system beefed up to cope with the new recycling technology.
+"I'm glad the community in Toowoomba rejected it because I don't think we're ready for it," he says.
+Australia also needs to concentrate on using its existing water resources more efficiently before turning to solutions like recycling, he says.
+Toowoomba's vote came ahead of the pending release of draft guidelines into the use of recycled sewage being developed by the Environment Protection and Heritage Council and the National Resource Management Ministerial Councils.
+The first half of the guidelines, dealing with recycled sewage for non-drinking purposes, is expected by September.
+The second half, which will deal with a range of issues including recycled drinking water, is scheduled to be released for public consultation in the middle of next year.
+Project Manager Ian Newbery says the documents don't recommend whether or not effluent recycling should be adopted as a source of drinking water.
+But he says the issue was included in the guidelines in response to Toowoomba.
+"When the guidelines were first mooted recycled drinking water wasn't actually on the priority list," he says.
+"It's because of the activity in Toowoomba and other places that it's actually now inserted.
+"It may be that once people get a handle on the risks involved and the treatment processes that you can go through there may be less angst about it."
+
+Scientists found this cyanobacteria in sandy and muddy marine sediments near Broome, Western Australia
+The oceans are teeming with 10 to 100 more types of bacteria than previously believed, many of them unknown to science, according to a new study.
+Using a new genetic mapping technique, US, Dutch and Spanish scientists say they found more than 20,000 different types of microbe in a single litre of water from deep sites in the Pacific and Atlantic Oceans. 
+"These observations blow away all previous estimates of bacterial diversity in the ocean," says lead author Dr Mitchell Sogin of the Marine Biological Laboratory at Woods Hole, Massachusetts.
+He says past studies have suggested that one litre of water would contain 1000 to 3000 types of microbe, the oldest form of life on the planet.
+Microbes make up more than 90% of the total mass of life in the seas, from bacteria to whales.
+"We've found 10 or maybe 100 times more diversity in sea water than anyone imagined was present," he says.
+The study is part of a global Census of Marine Life and is published today in the Proceedings of the National Academy of Sciences.
+Sogin says the findings suggest there might be more than 10 million types of bacteria in the seas alone.
+"If you're interested in new frontiers, things to discover, all you have to do is go to the ocean," Sogin says. 
+Until recent years, estimates of the total number of species on Earth were below a million.
+The new findings suggest that a swimmer swallowing a mouthful of sea water may be consuming perhaps 1000 types of bacteria.  
+The report says that many of the types of bacteria found at the sample sites,  including a hydrothermal vent at a subsea volcano off Oregon, are present in very low numbers, in what the researchers call a "rare biosphere".
+"Not only are they diverse from each other but they are very diverse from anything we have in the molecular database," Sogin says.
+The variety could upset normal understanding of the make-up of life in the oceans, and how it evolved. 
+One possibility is that some types of microbe are rare in some parts of the oceans but common in others, challenging traditional views of the seas as a homogenous bacterial soup.
+"There might be a 'biogeography' of microorganisms in the sea, something that microbiologists have been debating for perhaps hundreds of years," Sogin says. 
+Another possibility is that rare bacteria are tolerated in a habitat because they produce something, perhaps an enzyme or vitamin, that more common species need.
+A side-effect of tolerating scarce types of bacteria is that they might prove to be a reserve of spare parts to help ocean life rebound after some cataclysm such as a giant asteroid or an ice age, Sogin says. 
+Some rare species, for instance, might have genes allowing them to thrive if large tracts of the oceans freeze.
+Bacteria can exchange genetic material relatively easily, speeding adaptation and recovery of the total ocean population. 
+Sogin says the variety of life might also benefit pharmaceutical and biotechnology firms.
+"If you have a business plan based on drugs from diverse microbes the study should be very encouraging," he says.
+
+The latest study provides more evidence that men, like women, have a biological clock
+The risk of a miscarriage appears to rise along with the father's age, regardless of how old the mother is, researchers report. 
+Their study looked at nearly 14,000 women who were pregnant in the 1960s and 70s.
+The researchers found that the risk of miscarriage was 60% greater when the father was age 40 or older than when he was 25-29 years old. 
+What's more, age made a difference even for men in their 30s. Miscarriage risk was about three times greater when the man was 35-39 years of age than if he were younger than 25.
+These risks were all independent of the mother's age, a well-known factor in miscarriage, the researchers report in the latest issue of the journal Obstetrics & Gynecology. 
+The findings add to evidence showing that, like women, men have a biological clock. 
+Although men continually produce new sperm and can father children late in life, research shows that their fertility gradually declines starting at a relatively young age.
+Also, as with women, older fathers are more likely to have children with birth defects. 
+One recent study found that a man's ability to have a child fades after the age of 40, similar to a woman's fertility decline after age 35.
+Another confirmed that genetic abnormalities in sperm steadily become more common as men age. 
+Why does it happen?
+Miscarriages, particularly those in the first trimester, often occur because of genetic anomalies in the foetus, which may explain the risk tied to paternal age.
+The current findings strengthen the belief that people planning a family should consider not only the woman's age, but the man's as well, according to the study authors. 
+"As child-bearing is increasingly delayed in Western societies, this study provides important information for people who are planning their families," write the researchers, led by Dr Karine Kleinhaus, who was with the Columbia University School of Public Health in New York at the time of the study. 
+Back in the 60s and 70s
+The findings are based on data from a large study of women in Jerusalem who were pregnant between 1964 and 1976, about 1500 of whom suffered a miscarriage. 
+These women were compared with the more than 12,000 study participants who delivered a baby. 
+Older paternal age was linked to a higher miscarriage risk, regardless of both the woman's age and a range of other factors that contribute to miscarriage, such as smoking during pregnancy and maternal diabetes. 
+Still, the researchers point out, despite this generally higher miscarriage rate, older paternal age may only slightly raise the risk to any one couple.
+
+Jupiter's Great Red Spot, with its smaller cousin Red Spot Junior, seen through a special filter that samples thermal radiation from deep in the cloud layer
+Astronomers have taken images of Jupiter's lesser known red spot, a smaller landmark called Red Spot Junior.
+The smaller spot is about as wide as Earth and formed from the merger of three white spots sometime between 1998 and 2000.
+Red Spot Junior only turned red in December 2005, astronomers say.
+Using the Keck II telescope on Hawaii's Mauna Kea, scientists from the University of California, Berkeley, and the WM Keck Observatory captured a high-resolution picture of both small and large red spots late in July.
+Both are located in the same area and appear to be racing each other around the planet.
+The larger Great Red Spot rotates westwards, in the opposite direction to the planet, the scientists say.
+As alternating bands on the surface of Jupiter move in opposite directions, the nearby smaller spot moves eastwards.
+The two spots are about the same colour when seen in visible light, but Red Spot Junior is much darker when viewed at infrared wavelengths, the scientists say.
+That difference could mean the smaller storm's cloud tops are lower than the big storm's. 
+Astronomers have known about Jupiter's Great Red Spot, a high-pressure storm on the big planet's surface, for centuries.
+This better known spot is nearly twice its smaller companion's size and has been circling Jupiter for at least 342 years.
+
+Genes that control head size are puzzling researchers who say they may also play a role outside the brain
+The genes that are thought to have helped humans evolve big brains don't appear to play any role in how intelligent we are, according to a DNA study.
+This backs separate research that has failed to come up with a link between head size and intelligence, except in extreme congenital abnormalities.
+The Queensland Institute of Medical Research (QMIR) study is the first to specifically look at genes, head size and intelligence in a normal population.
+The Australian study found that people who scored highly in intelligence tests didn't necessarily possess versions of the genes that were expected to code for big heads and intelligence.
+And people who did possess the suspected 'smart' versions of the genes weren't necessarily the most intelligent or the ones with the biggest brains.
+The study will be presented at the 11th International Congress of Human Genetics in Brisbane next week.
+Head space
+The researchers tested 4395 teenagers for head size and intelligence.
+They also looked at the genes ASPM, MCPH1 and CDK5RAP2, which regulate brain size and activity.
+When mutated, these genes result in an abnormally small brain, a condition known as congenital microcephaly.
+"Normal variation in these genes has not yet been investigated in relation to head
+size and intelligence," says Dr Michelle Luciano, a research fellow at QMIR.
+She says the only comparable previous study used MRI imaging to measure brain volume in relation to two microcephaly genes.
+"Their findings [about a relation to brain size] were negative and they didn't find a relationship with two of the genes we were looking at," she says.
+"We decided to take it a step further and look at intelligence and lo and behold we find a similar negative result."
+Ancestral or evolved?
+We all carry the three genes the QMIR team investigated but some of us carry 'ancestral', or less evolved, versions and others carry 'derived' or more recently evolved versions. Some of us carry one of each.
+Researchers had expected that people with evolved versions of the gene would be smarter and have bigger heads, but were surprised to find this wasn't the case, Luciano says.
+"We would predict that if you've got the more recent version you should have a higher IQ," she says.
+"We actually found that not to be the case.
+"It is unlikely then that selective pressure for these genes is related to the evolution of intelligence in humans."
+Rather, she says the genes might be important for a neurological function outside the brain.
+Are humans getting smarter?
+Professor Colin Groves, an expert in human evolution from the Australian National University, says human brains began getting bigger after our earliest ancestors like Homo habilis appeared.
+But our brains have stopped growing and have actually started getting smaller, or at least more 'compact'.
+"[Our brains] have got bigger but they're not getting bigger," he says. "In fact since the late Pleistocene in general they've got smaller."
+While brain size appears to be related to intelligence between species, this doesn't seem to be the case within a species, Groves says.
+And despite the development of technological advances, he says there's no evidence that Homo sapiens has become more intelligent in the last 50,000 years.
+
+Nacreous clouds seen as the fading light passes through tiny ice crystals blown along on strong jets of air
+Rare, mother-of-pearl coloured clouds caused by extreme weather conditions above Antarctica are a possible indication of climate change, Australian scientists say.
+Known as nacreous clouds, the spectacular formations showing delicate wisps of colours were photographed in the sky over an Australian meteorological base at Mawson station on 25 July. 
+Australian Antarctic Division scientist Dr Andrew Klekociuk says such clouds are occasionally produced by air rising over Arctic and Antarctic mountains in high polar latitudes during winter.
+"You have to be in the right part of the world in winter, and have the Sun just below your horizon to see them," he says. 
+Nacreous clouds can only form in temperatures lower than -80&deg;C.
+Australian Bureau of Meteorology officer Renae Baker says a weather balloon in the vicinity of the clouds in the stratosphere about 20 kilometres above the Earth's surface measured temperatures as low as -87&deg;C. 
+"That's about as cold as the lowest temperatures ever recorded on the surface of the Earth," says Baker, who photographed the clouds.
+Klekociuk, an atmospheric scientist, says the rarely seen clouds, also known as polar stratospheric clouds, are more than just a curiosity. 
+"They reveal extreme conditions in the atmosphere, and promote chemical changes that lead to destruction of vital stratospheric ozone," he says. 
+Klekociuk says temperatures in the stratosphere, between 8 and 50 kilometres above Earth, would be expected to drop as the planet warms.
+Data collected over the past 25 years has reflected this, he told ABC Radio.
+"Over that time there has been a small decrease in temperature and that change is actually occurring faster than the warming at the surface of the Earth," he says. 
+The delicate cloud colours are created at sunset when fading light passes through tiny water-ice crystals blown along on strong jets of stratospheric air. 
+Winds at the same height were measured blowing at almost 230 kilometres per hour, the scientists say.
+Klekociuk says his colleagues and US researchers at the Davis station, 900 kilometres to the east of Mawson, are working together on research into what the strange clouds reveal about the atmosphere.
+
+Humpback whales shed skin in the water, which scientists scoop up in a kitchen sieve and analyse
+Researchers may one-day be able to tell how old a whale is by looking for clues in its sloughed-off skin.
+News of this noninvasive method, which relies on examining the tips of chromosomes, is published today in the journal Nature.
+Scientists are interested in finding out the age of individual whales to assess the impact of decades of commercial whaling and to learn about mating tactics and behaviour.
+Some whales can be aged by studying their teeth. But humpback whales don't have any so are aged by counting layers in their ear wax instead, a procedure that can only be performed on a dead whale. 
+Now researchers from the Whale Research Centre at Australia's Southern Cross University are developing another method.
+They trail behind the mammals in a boat. They then use a kitchen sieve tied to the end of a stick to scoop up flakes of skin, which can be the size of a hand.
+The skin is shed naturally when the whales soar out of the water or slap their tails onto the surface.
+The researchers believe they may be able to develop a system to work out a whale's age by removing genetic material from the skin samples. 
+Clues in the chromosomes
+They are studying the tips of chromosomes known as telomeres, which whittle away over time in some animals, like a countdown timer.
+By measuring the length of these telomeres and comparing that with a known rate of shortening, the researchers hope to estimate a whale's age.
+There are many hurdles to overcome, researchers admit. For instance no-one knows for certain whether all whales have telomeres that shorten with time. And not all skin flakes yield enough genetic material to analyse. Then the researchers have to calibrate their methods against whales of a known age.
+But the Nature report indicates that preliminary reports are encouraging.
+"If they are right, one of the key arguments in favour of killing whales for scientific purposes will be dead in the water," the report says.
+The researchers say the need for humane methods to age whales is now urgent, since Japan has declared it will increase its annual catch of whales for "research purposes", the report says. 
+The International Whaling Commission imposed a moratorium on commercial whaling in 1986 but Japan has continued hunting for what it calls scientific research.
+
+Scientists are analysing bone marrow from a frog that lived 10 million years before this one
+The first fossilised bone marrow has been found in the bones of 10-million-year-old frogs, salamanders and tadpoles, scientists say.
+Palaeontologist Maria McNamara says the find could tell us more about whether ancient creatures hibernated or whether they were cold-or warm-blooded. 
+McNamara, a researcher from University College Dublin, says her international team found the fossils in ancient lake deposits in the Libros area of northeastern Spain. 
+McNamara says one of the most exciting aspects of the discovery is what the marrow will be able to tell scientists about creatures that lived during the later Miocene period.
+"The original organic material is still there," according to McNamara, whose research was published in the latest issue of the journal Geology.
+"It is still organic in composition, whereas most traces of soft tissues you find in the fossil record, which are very rare anyway, have rotted away and just the shape of the tissue is preserved in mineral," she says. 
+"Tissue like bone marrow carries a lot of physiological information. It can tell you the state of the organism when it died, was it healthy, did it hibernate, where did it produce its red blood cells and whether it was warm-blooded or cold-blooded," she says. 
+"They would be pretty important to find for some other fossil groups like dinosaurs. It could help to resolve some debate about whether they were warm-blooded or cold-blooded," McNamara says. 
+She says researchers are now doing tests to see if any biomolecules, like amino acids or proteins, are preserved.
+McNamara, who is undertaking the research as part of work for a doctoral degree, says there are a number of reasons why fossilised bone marrow has never been found before. 
+"Because bone marrow rots away so quickly when people die, people never thought that it could be preserved," she says.
+"Also, because you have to fracture the bones before you can see inside, obviously if you have nice fossil specimens in a museum you are not going to get permission to break them up." 
+The researchers were able to access the marrow from the fossils because they were found in rock that had split and some of the bones had fractured as a result. 
+McNamara says the original red and yellow colours of the marrow have been preserved.
+"The fatty bone marrow is yellow and is a sort of energy reserve in terms of starvation or something and you also have red bone marrow and that is where your blood cells are produced," she says.
+"In the fossil bone marrow the original structure is preserved showing where the red and yellow marrow would have been but also the original colour is preserved and there are some cells preserved as well."
+
+Weather made the Earth wobble on its axis, like a wonky spinning top, in a rarely recorded event
+Scientists have confirmed that weather makes the planet wobble on its axis after exploiting a rare opportunity to detect and measure the most subtle shifts in the Earth's spin.
+The wobbling at the poles was in the order of centimetres, from the size of a 20 cent piece to the size of a DVD, says astronomer Thomas Johnson of the US Naval Observatory.
+"These loops are on the order of two or three days," says Johnson of the timeframe in which weather tugs and varies the direction Earth's axis is pointed in space.
+To see the weather wobbles, Belgian researchers took advantage of an unusual period from November 2005 to February 2006 when two better known, larger components in Earth's wobble cancelled each other out and no longer drowned out the signal of the smaller wobbles.
+The two larger components are a 433-day wobble thought to be caused by deep ocean current changes and annual wobble that corresponds to seasonal changes. 
+These change the position of the poles on about the scale of a baseball diamond, says Johnson. Every 6.4 years they cancel each other out.
+"It was basically now or never," says S&eacute;bastien Lambert of the Royal Observatory of Belgium of their well-timed measurements, which used GPS data to ferret out the weather effects.
+"We would have to wait more than six years for another chance."
+Lambert and his colleague V&eacute;ronique Dehant publish their findings in the journal Geophysical Research Letters.
+Lambert was also able to connect the specific wobbles seen during that period to atmospheric pressure systems over Asia and Europe. 
+This connection makes it possible to use weather forecasts to also forecast the smaller variations in Earth's wobble.
+Measuring these smaller wobbles is critical for navigational, timing and communication systems, says Richard Gross of NASA's Jet Propulsion Laboratory.
+"We have to know how the Earth's rotation is changing in order to track a spacecraft," Gross explains.
+At distances of tens of millions of miles, a few centimetres on Earth can make the difference between communicating with the spacecraft and losing contact altogether. 
+"It's most important when you are trying to land something on another planet," he says.
+On Earth the weather wobbles are also important because they can throw off models that are used to predict and correct for the larger wobbles, multiplying errors in GPS and military navigational systems.
+"The accuracy would be orders of magnitude worse" without these wobble corrections, says Johnson. 
+"At the latitude of Reagan National Airport [near Washington DC], the variation could be the difference between a plane landing on the runway or hitting the Potomac River."
+The wobbles also have to be accounted for when finely tuning clocks and the timing of satellite communications.
+"They all require Earth orientation data nowadays," says Johnson.
+
+A GM corn that could soon be approved for human consumption in Australia and New Zealand might produce similar toxins to those of concern in cooked red meat, say some scientists
+Australia and New Zealand's food regulator is failing to apply its own safety standards, or those of international guidelines, in assessing a new-generation GM corn for human consumption, critics say.
+But Food Standards Australia New Zealand (FSANZ) defends its so-far favourable assessment of the high-lysine corn, which it says is intended for animal feed and is unlikely to enter the human food chain.
+The Centre for Integrated Research on Biosafety at the University of Canterbury has twice formally notified FSANZ of its concerns about the GM corn, LY038, which has been engineered to contain a bacterial gene that allows the accumulation of high levels of lysine.
+"Among the types of potential hazards that this food poses are the creation of compounds that are known to be associated with important diseases like diabetes, Alzheimer's, heart disease and cancer," says centre director Associate Professor Jack Heinemann.
+Heinemann says while the compounds, advanced glycoxidation endproducts (AGEs), are also produced when cooking conventional foods, he is concerned about potential levels in LY038 corn.
+He says corn is normally extremely low in the compounds that combine to create AGEs. 
+But he says higher-than-normal levels of lysine in the LY038 and high sugar levels, combining under heat, have the potential to raise AGE levels.
+"[LY038] has the potential to produce 100 times more [AGEs] than normal corn," says Heinemann.
+Draft approval by FSANZ
+In March this year FSANZ recommended LY038 be approved as safe for human consumption in a report to its board.
+"Food derived from corn line LY038 is as safe and wholesome as food derived from other corn varieties," the report says.
+But the necessary tests to prove the corn is safe for humans have not been done, says Heinemann, a geneticist and former US National Institutes of Health scientist.
+He says LY038 is the first of a new-generation of GM foods being specifically designed to be nutritionally different from their conventional counterpart. And FSANZ's decision could set a precedent on how such foods are assessed.
+Tests of cooked corn?
+Heinemann says FSANZ only considered safety tests that looked at raw and not cooked corn.
+But the international standards-setting body Codex Alimentarius recommends heating, cooking and processing conditions be applied to GM material in an assessment of their safety for human food, says Heinemann.
+He also says FSANZ only considered 21-day animal studies and not longer ones, which might have picked up diseases like cancer. Heinemann says FSANZ should also look into human feeding studies.
+Lastly, Heinemann criticises FSANZ's decision to compare the composition of the corn to another GM corn rather than its non-GM parent variety, as recommended by its own advice, and by Codex.
+Safety assessment defended
+FSANZ says testing was adequate.
+"We are satisfied that we have all the scientific information necessary to make a sound decision on the safety and nutritional adequacy of high lysine corn LY308," it says.
+"We have considered the potential for production of AGEs, but have no concerns."
+FSANZ says Codex only asks regulators to consider testing heated or processed GM foods. But as the raw corn has much lower levels of lysine compared to other foods regularly consumed, FSANZ did not consider the tests necessary. 
+It also says the GM corn used for comparison was a "better comparator than the non-GM parental line".
+FSANZ says it assessed the corn as if it was any other GM food.
+"The safety assessment conducted on LY038 is as rigorous and thorough as for any GM food product, and assumes that if approved, corn from line LY038 could be routinely entering the food supply and not present just as an occasional inadvertent ingredient," states FSANZ's report.
+Will it enter the human food supply?
+FSANZ also says the corn is "unlikely" to end up in human food and is only being assessed as a precaution in case of an accidental mix-up.
+One such mix-up occurred in 2000, when Starlink GM corn, also intended for animal feed, became mixed in the US food chain.
+Because it was not registered for human consumption the contamination affected exports and cost the manufacturer a $100 million in lost sales.
+Canada approved the use of LY038 in the human food supply last month.
+The FSANZ board is due to consider the corn in late September.
+
+Could Epstein-Barr virus be transmitted via sex as well as kissing?
+Sex may increase the odds of contracting the glandular fever virus, a UK study suggests.
+This means that doctors and patients may have to rethink what they currently call the 'kissing disease'.
+The findings would also have implications for the vaccines now being tested against Epstein-Barr virus (EBV), which causes the disease.
+The study into this common condition in young people, also known as mononucleosis, is published in the journal Clinical Infectious Diseases.
+Of 510 college students who were initially free of EBV, nearly half became infected with the virus over the next three years, with sexually active students being at greater risk.
+Students who said they'd had intercourse during the study were more likely to become infected than those who reported no romantic relationships, as well as those whose relationships were limited to kissing and petting. 
+The findings suggest that sexual intercourse itself makes EBV transmission more likely, according to the study authors, led by Dr Dorothy Crawford of the University of Edinburgh.
+Most adults worldwide are infected with EBV, which, after first infecting a person, remains dormant in the body for life.
+Most of the time, the initial infection causes no apparent symptoms, especially when it's contracted in childhood.
+But in developed countries infection often doesn't occur until adolescence or young adulthood, when it's more likely to make people sick.
+Glandular fever is marked by often prolonged fever, fatigue, sore throat and swollen lymph nodes.
+According to Crawford's team, the new findings suggest that sexually active teens and adults may be exposed to a larger dose of EBV through particularly 'deep' kissing, or possibly through genital fluids, which can carry the virus. 
+If a large viral load increases the odds of developing glandular fever, the researchers note, then an EBV vaccine may be successful even if it merely decreases the amount of EBV in the body rather than providing complete immunity. 
+"We suggest that a vaccine that reduces the level of viral infection and/or replication during primary infection could be sufficient to prevent [glandular fever]," the researchers conclude.
+
+The Hawaiian Islands have a rich cultural history, as evidenced by these prehistoric etchings in lava rocks. Now archaeologists have discovered more about the rise and fall of civilisations on the island of Maui
+An ancient temple system on the Hawaiian island of Maui is about 400 years older than previously thought, according to an extensive archaeological study.
+The finding contradicts a prior theory that Maui's temples were built within a span of just a few decades around the year 1600.
+Some researchers now think the temples were built over the course of 500 years, with construction cycles peaking during periods of significant political change.
+"We see construction phases that parallel shifts in political control," says Associate Professor Michael Kolb, who led the study, which has been accepted for publication in the journal Current Anthropology.
+"Chiefs likely wanted to mark their territory. Whenever a new leader came into power, he would probably seek to validate his new political and ideological ideas through modification or expansion of the temple system," adds Kolb, a professor of anthropology at Northern Illinois University.
+Radiocarbon dating of charcoal from beneath the building foundations formed the basis of the new research. The charcoal remains were left behind after ancient builders cleared vegetation with controlled fires.
+Usually archaeologists rely on dating of ceramics, but ceramics did not exist in early Hawaiian history.
+"There is not a lot of soil formation on the islands, so the Polynesians who settled on Maui lacked clay and therefore pottery," Kolb says.
+Dating charcoal
+The charcoal dating determined that the Pihana temple, located in Halekii-Pihana State Park, is Maui's oldest temple. According to the new data, the existing ruins date to 1214.
+One of the island's best-known temples is Pi'ilanihale Heiau, which means The House of Pi'ilani, who was a popular chief.
+It is Maui's largest temple, covering more area than a football field and standing 12 metres in height. Pi'ilanihale was dated to 1294.
+The scientists believe this initial 13th century building phase was followed by subsequent periods of construction in the 14th century and again, during a particularly active phase, near the turn of the 17th century.
+Kolb explains that although Polynesians inhabited the Hawaiian Islands as early as the year 300, their settlements were initially small, spreading out over time. 
+Ancient Polynesians were once interested in ancestor worship and built small places of worship by paving off land and stacking rocks, according to archaeological evidence from early shrines in Hawaii and Tahiti.
+Over time, Polynesian culture shifted toward sacrificial worship, which led to the enormous platform temples, some built on cliff faces or other prominent spots.
+The most elaborate temples featured altars, oracle towers, offering pits, palisades, drum houses, and god or ancestral images carved from wood or stone.
+"The shock value of these temples for religious ceremonies must have been tremendous," says Kolb.
+"At some events there would have been human sacrifice, the killing of hundreds of pigs, the sounds of music and drumming, and the smell of burning fires. 
+"Members of the chiefly class were allowed into sacred areas of the temples, but they had to get in prostrate positions or lie down, sometimes for hours, as a sign of submission and respect for the chief."
+Contact with westerners
+The first westerners arrived with British explorer Captain James Cook in 1778. When Christianity was introduced to the islands in 1820, most of the temples were destroyed or abandoned. Maui has some of the best remains, with more than 120 remaining sites.
+Timothy Earle, a professor of anthropology at Northwestern University, agrees with the conclusions of the new study, which he says "involved the broadest set of carbon dates. They appear to be good and valid."
+Both Earle and Kolb believe the new findings suggest early Hawaiian monumental architecture was comparable to that of other famous ancient civilizations, such as the Maya or the early Egyptians, since all appeared to have linked temple construction to economic, political and ritual development.
+
+A robot army won't look like what we have come to expect from the movies
+A robot army could never be held morally responsible for committing war crimes, says an Australian ethicist, and so any wars they fight could be considered unjust.
+Dr Robert Sparrow of Monash University, who specialises in the ethics of new technologies, will lay out his argument in the Journal of Applied Philosophy.
+"To fight a war properly you must always be able to identify somebody who is responsible for the deaths that ensue," says Sparrow, who is also with the Centre for Applied Philosophy and Public Ethics at the University of Melbourne.
+"As this condition cannot be met in relation to deaths caused by an autonomous weapon system it would therefore be unethical to deploy such systems in warfare."
+Sparrow's article was triggered by his discovery that the military is the largest funder of robotics research. 
+For example, he says, the US military is developing an army that places autonomous machines in key roles on the front line.
+Currently, the army uses semi-autonomous robots in mine clearing and bomb disposal. And for any machine that kills people, there is always a human being that can be held morally responsible, says Sparrow.
+He says this applies, for example, to unmanned combat aerial vehicles that are programmed to help locate specific targets and fire on them, currently used in the Middle East conflict.
+But, asks Sparrow, what would happen if machines themselves were given the decision about who to kill?
+Autonomous killing machines
+Having killer robots on the front line instead of young men and women may be more politically acceptable, but will this mean any war crimes could be blamed on the machines, asks Sparrow?
+
+Radio tags have been used to track cattle for decades, where a security glitch is hardly a matter of national security. But how secure are the RFID tags in your passport?
+High-tech passports, touted as advances in national security, can be spied on remotely and their identifying radio signals cloned, computers hackers were shown at a weekend conference. 
+Radio frequency identification technology, or RFID, used in cash cards and passports, can be copied, blocked or imitated, says Melanie Rieback, a privacy researcher at Vrije University in the Netherlands. 
+Hacked chips could be used to launch attacks on software in computers linked to scanning devices, the doctorate student says.
+Rieback demonstrated a device she and colleagues built to hijack the RFID signals that manufacturers say can't be read by anything other than proprietary scanners. 
+The device is also designed to block scanners, legitimate or illicit, reading a tag.
+The researchers expect to have a reliable portable version of their device finished in six months and have "no plans to immediately mass-produce these things". 
+A cheer rose from the legion of hackers in the conference room when Rieback announced that the schematics and the computer codes for the device would be made public. 
+"The industry and government needs to not be scared of us," Rieback says. 
+She says RFID equipment makers would be wise to ramp up encryption and other security. 
+"If you are using RFID [to track] cows, who cares?" Rieback asks. "But with a passport, it only takes one breach at the wrong time and it could wreck it for the RFID industry." 
+RFID tags consist of a computer chips wrapped with tiny radio antennas. The chips store financial, identity, or other data that can then be sent to scanners by radio signals. 
+US retail behemoth Wal-Mart about two years ago embarked on a campaign to use RFID to track inventories and shipments from suppliers, and the devices are used to track cargo in shipping containers. 
+RFID tags have been used for decades to track cattle or wild animals. 
+Pet owners also have chips, about the size of grains of rice, implanted under the skin of their dogs or cats so they can be identified and returned if they run away.
+The European Central Bank has talked of putting RFID technology in euro currency, and such tags were used in World Cup Soccer tickets, according to the researcher. 
+Smart chips are being put into passports. Stores have experimented with using the tags not only to track inventory, but to bill shoppers for purchases invisibly as they leave.
+"It has been ... creating quite a stir," Rieback says of RFID use.
+
+A page from The Archimedes Palimpsest viewed by x-ray showing the hidden text
+Ancient writings by the legendary Greek mathematician Archimedes have been revealed for the first time in 1000 years.
+Scientists at the Stanford University Linear Accelerator Center used an intense x-ray to reveal the text as part of an ongoing study of the famous scholar's hidden work.
+The writings were recently revealed as part of a live webcast, which has been archived and can be viewed here.
+"We're getting a vastly better understanding of one of the greatest minds of all times," says Uwe Bergmann, a scientist involved in the project.
+"We are also showing it is possible to read completely hidden texts in ancient documents without harming them," Bergmann adds.
+The document in this case is The Archimedes Palimpsest, a goatskin parchment upon which a scribe copied seven important treatises of the Greek scholar, who lived from 287-212 BC.
+The hidden text was part of a work Archimedes called The Method of Mechanical Theorems, which proved to contain diagrams, equations and previously unknown letters.
+Historians are surprised that the manuscript even exists. Someone may have rescued the original papyrus version when the Royal Library at Alexandria, which contained monumental works by scholars from the ancient world, suffered a series of fires beginning around 89 BC.
+Many scientists believe that if all of the works of early scientists and mathematicians had survived, greater progress would have been possible during the Renaissance, as  academics wouldn't have had to rediscover principles already documented.
+It will take some time to determine, exactly, what the newly unveiled text means.
+But the rest of the document contains some of the earliest known references to geometry, physics and the concept of infinity, which later contributed to the invention of calculus.
+It also describes a puzzle game that was somewhat similar to Rubik's cube.
+In the 13th century, Greek monks recycled the parchment into a prayer book. Then 10th century forgers painted gold foil imagery onto the recycled pages in an effort to increase the manuscript's value.
+As a result, Archimedes' original text is buried beneath both the gold image and the prayers. Only the underside of the parchment hints at its original content.
+The manuscript's owner, who wishes to remain anonymous, paid U$2 million for the document at auction in 1998. Two conservators recently brought the rare text to California for the x-ray scan.
+"To my knowledge, this is the first time the Stanford equipment will be used for such an application," says Mary Miller, a science producer at San Francisco's Exploratorium museum, which hosted the event.
+Miller says that the high-tech equipment is often used to study photosynthesis in leaves at the molecular level. The powerful device is now tuned to read iron, which was in the ancient scribe's ink.
+Iron atoms have 26 electrons orbiting around a nucleus. The x-ray beam literally knocks out one of the electrons in the iron atom's innermost orbit.
+Another electron then replaces the missing one, but it has less energy because the nuclear bond is not as tight. The lost energy emitted by the replacement electrons results in the signature x-ray glow.
+
+Last year's Lockhart Review recommended that Australia's ban on therapeutic cloning be lifted. But the federal government has ruled out a conscience vote. So where does that leave research?
+The head of the UK genetics institute that produced the world's first cloned human embryo has accused Australia of damaging the international research effort by refusing to allow therapeutic cloning.
+Professor John Burn, medical director of the Institute of Human Genetics at the University of Newcastle upon Tyne, was commenting after Prime Minister John Howard ruled out a conscience vote on whether therapeutic cloning should be allowed in Australia.
+"It's a cost to the international research effort because Australia's a very important component of it and it's a shame that that position's been adopted," says Burn, who is in Brisbane for the 11th International Congress on Human Genetics.
+Therapeutic cloning, which involves the creation of an embryo for research and to  harvest stem cells, is distinct from reproductive cloning, which results in a human being.
+Both practices are currently banned in Australia although the independent Lockhart Review last year recommended the ban on therapeutic cloning should be scrapped.
+Burn's unit received Europe's first cloning licence in 2004 and researchers announced the following year that they had created a cloned embryo by somatic cell nuclear transfer.
+This year his team reported they had produced mice from sperm grown from embryonic stem cells.
+A shadow over stem cell research
+But the UK's 2005 cloning achievement was overshadowed by South Korean Professor Woo Suk Hwang.
+Hwang had apparently beaten Burn's team by claiming just months before that this  team had cloned human embryos and produced stem cell lines from them.
+Hwang later admitted fabricating that claim.
+The scandal was a major setback for embryonic stem cell research, Burn says.
+He says it damaged the credibility of the field and had made it harder for scientists to do their work because it had brought about increased regulation and requirements.
+"Although we were very pleased to have actually been the first, it did cast a huge shadow over the whole field and every paper submitted now has to be backed up with endless evidence," he says.
+Prime Minister John Howard ruled out a conscience vote on therapeutic cloning over the weekend but says he is still happy to have a party room debate on the matter.
+Forcing a brain drain
+Burn says the Australian government is making an ill-informed and "too cautious" decision not to adopt the recommendations of the Lockhart Review.
+The decision will continue to force Australia's top scientists offshore, he says.
+"Clearly if people feel unable to work on a topic they will move," he says.
+He says the University of Newcastle upon Tyne has formed an alliance with Melbourne's Monash University to work on embryonic stem cell research.
+"It may well be that by strategic alliance the Australian scientists will find a way around the federal obstruction," he says.
+Burn says the promise of stem cell research is "absolutely undeniable".
+"I think if the Prime Minister approaches this in a democratic way then the vast majority of Australians would want this research to go ahead," he says.
+"And I think the vast majority of Australians would say if it's OK in Britain we can't see why it's not OK in Australia."
+
+Canada geese fall sick when they eat designer grass laced with fungus
+Designer strains of grass could one day be used to keep birds away from golf courses and airports, New Zealand scientists say.
+Research into these smart grasses is discussed this week at the Agricultural Biotechnology Industry Conference in Melbourne.
+Chris Pennell and his colleagues at Ag Research New Zealand have been working on particular types of fungi that co-exist with grass.
+These fungi, called endophytes, live in the spaces between plant cells.
+By choosing the right combination of endophyte and grass, the researchers hope to produce turf with unique properties.
+Some endophytes repel insects and others are toxic to livestock that graze on them, Pennell says.
+Over the past two decades, he and his colleagues have been working to find the right combinations of grass and fungus to offer the benefits without the toxic side-effects.
+"We've been looking for the friendly endophytes," Pennell says of the research, which has mostly been for the livestock industry.
+More recently, the researchers have also begun designing grass and fungus combinations to keep birds away.
+Insects can't eat these grasses, which deprives some birds of their food source. 
+They can also give grass-eating birds such as Canada geese an illness the researchers call "post-ingestion malaise". 
+"When herbivorous birds eat this grass they get sick and then they don't come back again," says Richard Curtis, business development manager at Ag Research New Zealand.
+The idea is that for airports, planting grass that keeps insects and birds away could help reduce dangerous birdstrikes where our feathered friends collide with aircraft.
+In the past few months, the team has planted test plots of the grasses at Christchurch International Airport. The early results are promising, Curtis says of the research, which the airport helped to fund. 
+"It won't solve all the problems with birds around airports, but it'll be a part of the overall bird management armoury," he says. "There is a lot of interest from airport companies around the world." 
+Meanwhile, the scientists are also applying the technology to golf courses, where fouling from birds like Canada geese can spoil a day on the greens.
+Early trials on New Zealand golf courses shows that planting a 10 metre strip of the smart grass around waterways keeps geese and other birds away, Curtis says.
+"They just packed up and went to other parts of the golf course."
+
+Is this an accurate representation of actor Nicole Kidman? Or is she fatter or thinner in real life? These questions are the basis of new research into body image
+People who are unhappy with their own body are likely to think celebrities are thinner then they really are, new Australian research shows.
+The study is more evidence that being dissatisfied with your body is likely to distort your perception of other people's bodies. 
+Lead researcher Amy Willinge, who is undertaking a doctorate of clinical psychology at the University of Sydney, reports the findings online in the International Journal of Eating Disorders.
+She asked 118 normal weight university students, mostly aged 17 to 22, to study actual photographs of thin female celebrities and computer-altered images showing them as thinner or heavier. 
+Participants chose the image they thought was the actual size of each celebrity and which they thought was the 'ideal' size for a female.
+The five 'underweight' celebrities were Nicole Kidman, Kylie Minogue, Holly Valance, Angelina Jolie and Sarah Jessica Parker.
+Each had one full-length photo of their true size and six others which were 10%, 20% and 30% thinner and heavier than reality, displayed randomly on the same screen.
+When trying to identify the actual photos, body-dissatisfied males and females chose images that were significantly thinner than in reality.
+They also chose an ideal size thinner than the celebrity's real size.
+People who were satisfied with their body were more realistic and accurate in judging celebrities' actual sizes.
+While body-satisfied females picked ideals that were larger than the celebrity's real size, males viewed thin as the female ideal.
+"The research suggests that if people are not satisfied with their own body, it may lead them to distort their perceptions of others' bodies, and forge unrealistic attitudes towards ideal body sizes, setting themselves up for an increased risk of eating disorders, low self-esteem and depression," Willinge says.
+"The finding that body satisfied and dissatisfied males identified a very thin body size as ideal for women indicates there is increasing pressure from society on women to be thin.
+"Media presentation of thin female images is affecting males' attitudes towards female bodies, putting increasing pressure on females to obtain the idealised body image."
+But she says the findings absolve the media of some blame as it is not just presentation of thin images that results in body dissatisfaction but the way body-dissatisfied people view images.
+
+But it's still not clear how this research relates to brain development in humans
+Ultrasound disrupts the brain development of unborn mice, US researchers say in a study that adds to growing evidence that too many scans could also affect human foetuses.
+Prolonged ultrasound scans of the brains of foetal mice interfered with a process known as neuronal migration in which neurones move from one place to another, the team at Yale University reports. 
+"Proper migration of neurones during development is essential for normal development of the cerebral cortex and its function," says Dr Pasko Rakic, chair of the Department of Neurobiology at Yale.
+"We have observed that a small but significant number of neurones in the mouse embryonic brain do not migrate to their proper positions in the cerebral cortex following prolonged and frequent exposure to ultrasound." 
+Writing in the Proceedings of the National Academy of Sciences, Rakic's team says the findings do not necessarily mean that ultrasound of human foetuses is dangerous.
+But the researchers say doctors and pregnant women should probably keep the scans to a minimum.
+The pros and cons
+Ultrasound scans give parents a peek at the unborn child and doctors a chance to see if there are any serious defects that might be corrected before or right at birth.
+But several studies suggest that ultrasound may affect the developing brain, not necessarily adversely.
+For instance, a 1993 study published in The Lancet journal found that foetuses exposed to ultrasound in the womb were more likely to be left-handed.
+A separate study found a possible decrease in weight in newborns who were scanned, while a third found delayed speech. 
+But another study showed that children who had received ultrasound exams before birth actually did better on language tests when they were older, says Dr Verne Caviness of Massachusetts General Hospital.
+More study is clearly needed, Rakic says.
+"We do not have any evidence ourselves that ultrasound waves cause behavioural effects in mice or have any effect on the developing human brain," he says.
+"Therefore I want to emphasise that our study in mice does not mean that use of ultrasound on human foetuses for appropriate diagnostic and medical purposes should be abandoned.
+"On the contrary. Ultrasound has been shown to be very beneficial in the medical context," Rakic adds. 
+He says the study suggests that pregnant women should not get multiple ultrasound scans for fun or out of curiosity.
+The mouse study
+For their study, Rakic and colleagues did scans of pregnant mice on the 16th day of gestation. 
+This is the last week of gestation and a time when, in mice, neurones move to a new position in the brain.
+After prolonged, multiple scans, some of these cells went to the wrong place. 
+"Does this study indicate that we should be concerned about human foetal ultrasound?" Caviness asks in a commentary published in the same journal. 
+He says the implications are not known and notes a human foetus has a much larger and denser brain, and that scans usually just pass over the brain for a few seconds. 
+"The corresponding neurones in the human brain would probably be formed in the 16th week and continue to migrate for at least 1-2 weeks," Caviness writes.
+No one knows how sound waves might disturb a developing foetus or embryo, both Caviness and Rakic say.
+
+The project aims to collect DNA and other health information from 2 million volunteers
+Researchers plan to collect blood samples and health information from every living member in Western Australia over the next few years in a move they say will create the world's biggest human genetic databank.
+Professor Lyle Palmer, from the University of Western Australia Centre for Medical Research, is leading the team that will hopefully collect samples from 2 million volunteers.
+Next year, the scientists hope to collect some 3500 pieces of information per person from the first 60,000-80,000 people.
+Palmer told the 11th International Congress of Human Genetics Congress in Brisbane it will be the first step in the proposed Western Australia Genome Health Project, one of a number of so-called biobanks that are being established around the world.
+Palmer estimates such a project would cost "several hundred million dollars" and the team will be seeking support from the federal government along the way.
+"The obvious thing to do ... is to study the whole population," he says.
+"We'll be doing things like full body scans on everyone, full respiratory and cardiovascular work-ups, we'll  be taking pictures of everyone's retina, [doing] hearing assessments, we'll be scanning thousands of brains.
+"It's about three days of data collection on each person, some of which will happen at schools, some at home, some at central facilities."
+Everyone including children will be asked to participate, Palmer says. 
+Data will also be collected from indigenous Australians, although this will be done under a separate umbrella with indigenous input.
+The perfect population
+Palmer says Western Australia is well suited to this kind of study because it's an isolated yet outbred population with a relatively low migration rate and historically large families.
+It also has extensive existing records, much of the necessary infrastructure, including the Western Australian DNA bank, and what he says is the biggest linked health database in the world.
+Palmer says the rising incidence of chronic disease together with an increasingly unsustainable health system and the growth of new tools and technology has made the project not only possible but necessary.
+He says national privacy legislation and beefed up genetic data protection laws, in line with the recommendation of the Australian Law Reform Commission's Essentially Yours report, will ensure privacy is safeguarded.
+"You're asking people to donate their sample for ever and ever so of course you have to very carefully work through those issues and that's what we're doing at the moment," he says.
+However, information will be linked to individuals via a code to ensure they can be followed up, he says.
+
+Pressure to have predictive genetic testing is coming from a surprising source, a new study shows
+People are coming under more pressure from family members than doctors and even insurance agencies to have genetic tests, an Australian study reveals.
+The findings are contained in the final report of the community component of the long-awaited Genetic Discrimination Project, which was presented at the 11th International Congress of Human Genetics in Brisbane today.
+Chief investigator Associate Professor Sandra Taylor of Central Queensland University told the conference that 32% of respondents reported feeling as if their family had forced them to undergo predictive genetic testing, the type that gauges a person's chance of developing a disease.
+"We asked people had they experienced coercion, or felt coercion in terms of undertaking testing, and most respondents answered no they had not," she says.
+"When reported, however ... the category most frequently reported was within the context of the family itself, follow by doctors, genetic clinicians, researchers and insurers."
+But she says family pressure doesn't necessarily refer to "coercive events", but rather people's perceptions of what's expected of them.
+"So in the family context, people may feel coerced just because they want to help establish the risks of other people in the family without necessarily other family members applying pressure."
+Discrimination
+The study surveyed 951 adults who had tests for inherited conditions including neurological conditions, cancer and the blood disorder haemochromatosis between 1998 and 2003.
+A total of 11%, or 107 of the 951 respondents, reported one or more incidents of discrimination.
+Of those that had experienced discrimination, most said they experienced negative treatment by life insurers and bosses; some felt family and personal relationships were adversely affected and others felt discriminated against by healthcare providers.
+The report also found that most people either didn't know where to go to complain about negative treatment or didn't want to, citing red tape and concern about consequences.
+"We would think that there's a need for increased education ... about consumers rights regarding seeking review or making complaints about negative treatment," Taylor says.
+However, people also said there were considerable benefits from having a test.
+Genetic tests in the workplace.
+Meanwhile, a separate section of the report looking at discrimination by employers and life insurance agencies found that in 92% of the cases investigated between 1999 and 2003, insurance companies had acted reasonably.
+There were only three cases of apparently "unreasonable" insurance underwriting relating to people who tested positive to the breast cancer genes BRCA1 and BRCA2.
+The first national study of its kind, the third-party survey also found "negligible evidence" that genetic tests were being used by the 381 employers surveyed.
+None had asked for a genetic test to be done and only one employer had asked for a previous test.
+However, there is strong potential for the use of genetic test information to increase in future, investigator Professor Margaret Otlowski of the University of Tasmania told the conference.
+"In order for ... consumers to feel confident about that future clear guidelines must be in place," she says.
+
+Carp make up to 90% of fish biomass in some Australian rivers, putting pressure on native fish
+Australian carp may have originated from Germany, according to preliminary results from a genetic study.
+The researchers say their findings, from the largest and technically sophisticated genetic study of carp in Australia, is also beginning to shed light on what caused them to become the cane toads of the country's rivers.
+University of Sydney PhD student Gwilym Haynes has been working with the New South Wales Department of Primary Industries and CSIRO to sample carp from every major river in the Murray-Darling basin, as well as coastal rivers, and from Japan, Russia and Germany.
+By analysing nuclear and mitochondrial DNA he's tracing the history of the freshwater pest's invasion.
+The preliminary results were presented at the 11th Congress of Human Genetics in Brisbane this week.
+"The Australian carp cluster to the German carp which indicates they have mostly German ancestry," he says.
+Boolarra carp
+Carp, Cyprinus carpio, were first introduced to southeastern Australia in the late 1800s but didn't become a problem until a fish farmer released a particularly robust strain in the town of Boolarra, in Victoria, in the early 1960s.
+Haynes' research suggests the Boolarra strain bred with existing koi, or Japanese carp, from earlier releases and began their colonisation of the southeastern waterways.
+The study could also resolve the question of whether the Boolarra strain was illegally imported or obtained locally from a population in the Prospect Reservoir in New South Wales.
+"The official story is that they came from Prospect but other people say they were imported from Europe," Haynes says.
+"It does look like the strain which is supposedly responsible for the carp being so widespread was European and didn't need a lot of input from the Asian carp to do well.
+"It implies that the carp were probably well adapted when they got to Australia and didn't need to breed with the other Australians to do well."
+Almost everywhere
+Carp are currently established in every Australian state and territory except the Northern Territory. 
+They pose a serious problem in Australian waterways, where they can make up to 90% of fish biomass in the rivers, putting pressure on native fish.
+Haynes says carp are likely to remain a pest and "will certainly establish themselves in new regions".
+Understanding their genetics will make them easier to control, he says.
+"There is significant genetic differentiation within regions in Australia, and this has implications for carp management," he says.
+"These regions should probably be managed separately to get the best result."
+
+Forget Mars this month, say astromomers. Look for Jupiter instead
+A repeat of last year's spoof email promising that Mars will look as large as the Moon later this month is causing headaches for astronomers and science educators.
+They say that the Mars hoax appears to be just as resilient as the Moon hoax, which denies the Moon landings ever happened. 
+For instance, Jennie McCormick, education officer at Auckland's Stardome Observatory, says Stardome, like many other astronomy education centres, has been fielding numerous calls for the past fortnight from people wanting more information about the bogus event.
+"The email originally dates from the 2003 opposition of Mars when the Red Planet was very bright and spectacular because it was closer to Earth than it had been for about 60,000 years," she says.
+"But it certainly didn't and couldn't look as big as the Moon. You need to read the email carefully to notice that Mars would only look as big as the Moon through a telescope which had magnified it 75 times."
+She says that Mars does vary in brightness as its distance from Earth changes.
+"[But] without a telescope it will never look much bigger than an ordinary star."
+Contrary to the email, this month Mars will be very low in the sky and only just visible in the west after sunset.
+Teachers have also been fooled by the hoax.
+"We've had several calls from children whose homework has been to find out what planet is going to be bigger than ever before," says McCormick.
+"The hardest thing is having to disappoint children who are clearly excited by what they think they are going to see. That is the sort of thing that turns them off science, when astronomy is something that usually turns them on to it." 
+However, she takes the opportunity to tell them although Mars may be disappointing this month, the giant planet Jupiter is well placed for observing.
+"It's actually much more spectacular than Mars because it is bright and easy for them to find and, with good binoculars, they can see the planet with four of its moons," she says.
+McCormick also tells them to check out the Bad Astronomy website, which uses science to debunk hoaxes like this.
+Not everyone is as concerned as McCormick about the Mars email, like Alan MacRobert, a senior editor of Sky & Telescope magazine.
+"I see it as a good thing, not a bad thing. It's an immunisation. If you make a fool of yourself by sending it to your friends and family, you'll be less likely to send them the next email chain letter you get, which may not be so harmless," he says.
+
+Is the culture that produced this wood carving predisposed to violence? A new genetic study says 'yes'. But how much do social issues explain the crime statistics?
+A New Zealand scientist says the country's indigenous Maori people have a 'warrior' gene which makes them more prone to violent and criminal behaviour.
+Dr Rod Lea revealed his theory this week at the 11th International Congress of Human Genetics in Brisbane, Australia, acknowledging that it is controversial to suggest an ethnic group is predisposed towards criminal behaviour. 
+Maori leaders immediately panned his claims.
+Maori Party co-leader Tariana Turia told The Press newspaper that while she had heard of Maori having a genetic predisposition towards alcoholism, it was a big leap to include violent tendencies. 
+"I realise that violence is an issue to us, but there are very common factors as well with violence which are not really related to race." 
+Lea, a genetic epidemiologist at the Institute of Environmental Science and Research in Wellington, says that Maori men have an over-representation of monoamine oxidase, dubbed the warrior gene, which is associated with aggressive behaviour. 
+The gene was discovered by US researchers but has never been linked to an ethnic group.
+He told New Zealand's National Radio that the gene appeared to feature in about 60% of Maori men compared with 30% men of European descent. 
+"I believe this gene has an influence on behaviour of humans in general, but I also believe that the influence is rather small," he says. 
+"We have to be clear that behavioural traits such as susceptibility to addiction, aggressive behaviour, risk taking, all those sort of things are extremely complex and they are due to numerous factors including non-genetic environmental factors like upbringing and other lifestyle factors." 
+Lea says the gene explains some of the issues involving Maori.
+"They are going to be more aggressive and violent and more likely to get involved in risk-taking behaviour like gambling," he says, although he believes other, non-genetic factors might also be at play.
+"There are lots of lifestyle, upbringing-related exposures that could be relevant here so, obviously, the gene won't automatically make you a criminal."  
+Maori MP Hone Harawira believes social issues, including high unemployment, poor educational achievement and in many cases severe poverty, to be the main contributors to Maori violence rather than a warrior gene. 
+"If you put any group in that situation ... I dare you to point at the group that wouldn't be aggressive as a result of being treated that way." 
+National Urban Maori Authority chief executive John Tamihere says he is open to research-based evidence on whether there is a genetic reason for the over-representation of Maori in violence statistics.
+
+The chromosomes we have today may not be the ones we'll have in 15 million years. So, what will this mean for the future of our species?
+The pending demise of the Y chromosome could give rise to a whole new species of human, a professor of comparative genomics says.
+Scientists have been speculating about the demise of the Y chromosome for some years now but Professor Jenny Graves of the Australian National University in Canberra has come up with a bold new twist on the theory.
+Graves, who has been working on sex chromosomes in marsupials, will present her theory at the 11th International Congress of Genetics in Brisbane today.
+She will tell the conference that new 'male making' genes on other chromosomes could step up to do the job of the Y chromosome's SRY gene, which is the key to making males male.
+But this could mean men without Y chromosomes would split off from those with, eventually evolving into a new species of hominid.
+"It's quite possible that you could make new hominid species that way," she says.
+When two populations become two species
+Graves says men without a Y chromosome would be largely infertile. But a small number would reproduce and pass the new sex determining gene to their children.
+Eventually the group with the new gene would separate from the Y gene group, potentially evolving into a new species, she says.
+"[The two groups] couldn't mate with each other so they'd get gradually different, just like chimpanzees and humans gradually became different 5 million years ago," she says.
+"When two populations become two species there's generally there's some sort of wedge driven between them so they can't mate with each other.
+"It might be a mountain range ... but it might be something fundamental like the way they determine sex has flipped to some new way."
+15 million years and counting
+Graves says there are only 45 working genes left on the Y chromosome from "a grand total" of 1400. 
+It also contains a lot of 'pseudo genes', which look like they should work but don't, suggesting they've recently become defunct.
+According to her projections the Y chromosome will disappear altogether in 15 million years.
+This will occur because unlike the other coupled genes, the single Y chromosome can't recombine with a matching partner and is less able to refresh itself.
+Mutations will build up and the mutated genes will eventually drop off the chromosome because they no longer perform any useful function.
+Graves says this has already happened in the case of the mole vole, an aggressive little rodent that appears male and is able to reproduce despite having lost its Y chromosome.
+XX men
+Australian researcher Professor Andrew Sinclair, of Murdoch Childrens Research Institute, is researching so-called XX men, or the roughly one in 150,000 men who are born without a Y chromosome.
+"What it's pointing to is the presence of new genes we haven't yet discovered to replace the ones on the Y chromosome," Sinclair says.
+Alternately, the "volume" of previously existing genes may have been "turned up" in the absence of the Y genes, he says.
+Sinclair's team is the first in the world to use new high-density gene chips to examine XX men in the hope of finding out which genes these are.
+About 10% of affected men also have a tiny portion of the Y chromosome stuck on their X chromosome which carries across the testis determining gene, he says.
+Sinclair says Grave's theory about a new human species could make sense "in a theoretical way" but is unlikely in reality.
+"I don't know about a whole new species of human but if you lost the Y chromosome completely males would have to evolve in some way to deal with it," he says.
+"If you have males without a Y chromosome I don't think I'd go as far as calling them a new species, but a new type of individual."
+
+The study relied on over 50 ice cores collected from a range of locations around Antarctica
+A new study that shows Antarctic snowfalls have changed little in 50 years, despite global warming, could be evidence that the worst is yet to come, says one of the authors.
+A study published today in the journal Science reports that, contrary to expectations, snowfall in Antarctica has not increased over the past 50 years.
+This contradicts the predictions of most climate models that are based on the assumption that warming air can carry more moisture and produce greater snowfalls at the poles.
+"The models predict that Antarctic snowfall should be increasing with a warming atmosphere," says Australian team member and palaeoclimatologist Dr Ian Goodwin, of the University of Newcastle.
+Goodwin doesn't challenge this basic climate physics. But says the recent evidence supports the idea, not recognised in climate models, that there is a lag between global warming and Antarctica's response to it.
+The reason is that Antarctica and the southern hemisphere are surrounded by large oceans that take a long time to heat and therefore act as a buffer to climate change.
+Recent evidence suggests the lag time could be up to 60 years, says Goodwin.
+"We can be relatively complacent about the effects of climate change in the Southern Hemisphere because we haven't seen dramatic changes," he says.
+"But the frightening thing I think is that we are not yet seeing the full impact of global warming in the southern hemisphere. But it's just around the corner."
+Natural cycles
+Goodwin and colleagues published a study in 1991 that showed an increase in snowfall in east Antarctica.
+But, the new study shows that since then, the amount of snow falling in that area has decreased.
+Goodwin and colleagues used direct measurement of snowfall and more than 50 ice cores to reconstruct annual snowfall over the past 50 years.
+He says the study demonstrates a previously unknown natural climate cycle, affecting the whole of Antarctica.
+"On one side of Antarctica in some decades we see an increase in accumulation [of snow] and on the other side of Antarctica we see a decrease and so it balances out to zero net gain," he says.
+Goodwin says this variability is so great it could mask any changes due to global warming.
+But, he says, it could only be a matter of time before the natural cycle becomes dwarfed by the changes brought about by global warming.
+And this is where he says the lag time becomes important.
+"If we were to rewrite this paper in say 10 years time the likelihood is that we will be actually be writing a paper that says 'significant change in Antarctic snowfall over the last 10 to 15 years'," says Goodwin.
+"In all likelihood we're about to see, in the next couple of decades, a very large response to global warming in Antarctic and Southern Ocean regions."
+Goodwin says that the new research should now feed into climate models and make them more accurate.
+
+Embryo of the penis worm (Markuelia), showing the embryo as a whole (top) and the part of the embryo that would have developed into the digestive tract (bottom)
+The first 3D images of the dawn of life have been made possible using a new technique allowing virtual dissections of half-billion year old fossil embryos, scientists say.
+The images, including those of ancient penis worm embryos, are published today in the journal Nature.
+Among the images were those of fossils from the genus Markuelia, found in China and Siberia, which date from the Cambrian period.
+The new imaging method reveals a universe of detail impossible using previous methods, from the first splitting of cells to just before hatching.
+The researchers, including those from the UK's University of Bristol, say their technique pushes back the frontiers of science much as the scanning electron microscope did half a century ago.
+"We are looking at the dawn of life," says lead researcher Dr Phil Donoghue.
+"Because of their tiny size and precarious preservation, embryos are the rarest of all fossils.
+"But these fossils are the most precious of all because they contain information about the evolutionary changes that have occurred in embryos over the past 500 million years."
+Until now, if scientists had wanted to study fossil embryos, they had to look at them from the outside or cut narrow slices of the embryos, which obviously destroys them.
+But this new method, known as synchroton-radiation x-ray tomographic microscopy or SRXTM, leaves the tiny fossils untouched, yet gives graphic details of their structure.
+Accelerating particles
+The researchers used a 500 metre wide particle accelerator in Switzerland to deep-scan the minute fossils.
+They then fed the information into a computer to generate complete 3D images of the internal structures in fine detail.
+"The best analogy is with a medical CT scan ... but at 2-3000 times the resolution," Donoghue says.
+"We can see details less than 1000th of a millimetre in dimension.
+"We can look at any and every part of the fossil, inside and out, without harming it and then virtually dissect it however we like."
+The team says its discovery could roll back the evolutionary history of arthropods like insects and spiders.
+In one case they had found hitherto hidden details of the interior structure of an ancient relative of the living penis worm, and in another they had seen embryonic worm segments unlike those found in living specimens today.
+
+The new study supports the idea that an infectious cell line is threatening to wipe out the Tasmanian devil
+Dogs can 'catch' cancer by having sex with infected dogs, or perhaps by licking, biting or sniffing them, UK researchers show.
+The evidence for infectious tumour cells lends weight to a new form of cancer transmission, which some researchers believe is how Tasmanian devils catch their deadly facial tumour.
+Dr Claudio Murgia of University College London and colleagues report their findings in the current issue of the journal Cell.
+The researchers studied unrelated dogs worldwide with the canine transmissible venereal tumour (CTVT), also known as Sticker's sarcoma.
+They found that the DNA sequences isolated from tumour and blood samples were different.
+"We saw the tumour cells didn't belong to the dogs," Murgia says.
+Instead, the team says, the tumours from the dogs were closely related and had all come from single cancer cell that had evolved into a parasitic form.
+This had been passed on from dog to dog through sexual contact and possibly through licking, biting and sniffing tumour-affected areas.
+Murgia and colleagues say the cancer arose at least 200, and possibly 2500, years ago in either a wolf or a closely related ancient dog breed, making it the oldest cancer known to science.
+Tasmanian devil tumour
+Earlier this year Australian cytogeneticist, Anne-Maree Pearse of Tasmania's Department of Primary Industries and Water and colleagues reported preliminary evidence to support their theory that an infectious cancer cell line was responsible for the debilitating facial tumour killing endangered Tasmanian devils.
+Pearse found that the chromosomes in the cancer were so complex they must have taken a long time to evolve. 
+She found the same chromosome types in tumours from both males and females. And she found a devil that was born with a chromosomal abnormality did not have that abnormality in its tumour cells.
+"There's no other explanation for my results," Pearse says.
+"It shows absolutely that it is the cell itself that is being transmitted from animal to animal," she says. "It is the cell that's the parasite."
+
+Position of the Sun at different times of day, as depicted in Monet's Houses of Parliament
+Claude Monet's renditions of foggy London could be the earliest coloured record of the notorious 'pea souper' smog that wrapped the British capital at the turn of the 20th century, according to a scientific analysis of the artist's London series.
+The study, published in the current issue of the Proceedings of the Royal Society A, show that Monet's paintings of the House of Parliament were not created from his imagination.
+On the contrary, they were firmly based on actual observations made during the artist's visits to London.
+A founder of impressionism, Monet (1840-1926) made three trips to the city between 1899 and 1901, producing hundreds of paintings.
+Showing the Sun struggling to filter through the mist and smoke of Victorian London, the paintings depict the most famous global meteorological phenomenon of the 19th and 20th centuries.
+The paintings show three views of central London engulfed by fog.
+Two southward views are from the Savoy Hotel, where the French artist had a room, and one westward view is of the House of Parliament taken from St Thomas' Hospital.
+Among the 95 paintings of the series still existing, only 12 are dated between 1899 and 1901. A total of 61 are dated between 1902 and 1905, and 22 are undated.
+This has suggested that Monet dated his works to the time they were completed or sold, when he had already returned from London to his home at Giverny in Normandy, northern France.
+"There is some uncertainty as to whether the paintings are reasonably accurate depictions of observations, one of the tenets of impressionism, or whether the final paintings were rather creations of Monet's imagination in his studio in Giverny," says Dr Jacob Baker, of the University of Birmingham.
+Where's the Sun?
+To establish whether Monet's paintings are a fair rendering of what he observed, Baker and his colleague Dr John Thornes, from the School of Geography, Earth and Environmental Sciences, analysed the position of the Sun in nine of Monet's paintings showing the Houses of Parliament.
+The researchers turned to astronomical data from the US Naval Observatory to trace the Sun's position over Parliament during the artist's stay in London. They compared this data to the position of the Sun in the paintings.
+Along with information in Monet's letters to his wife, the results revealed that Monet painted his Parliament pictures all in the afternoon, between 14 February and 24 March 1900.
+Further calculations made it possible to discover the exact spot from which the French artist painted the pictures: a second floor covered terrace of the former Governor's Hall at St Thomas' Hospital.
+"We are confident that these paintings show an accurate visual record of the urban atmosphere of Victorian London," Thornes says.
+Great fog
+London's 'great fogs' reached a peak in the late 1880s, then gradually declined. 
+But little is known about the nature and causes of the phenomenon, due to the absence of air quality monitoring at the time.
+"The Victorian fogs tended to be associated with industry, employment and wealth to the minds of Londoners at that time. Air quality and health-related issues tended to be neglected," Baker says.
+Baker and Thornes are now planning further detective work on Monet's colours to determine the size, density and composition of Victorian fog particles.
+
+The invasive red corals are crowding out the native cream ones 
+Polluted water helps exotic species to invade marine areas, an Australian scientist has found.
+These exotics can become tolerant to metals like copper, which gives them a selective advantage over native species.
+Marine ecologist Dr Emma Johnston, of the University of New South Wales, presented her team's research at the recent Australian Marine Sciences Association conference in Cairns.
+Scientists know that ships inadvertently transport marine organisms all over the world, allowing a relatively small number of 'weedy' exotic species to crowd out more diverse communities of native species.
+"There's a problem with the homogenisation of the world's biota where places such as harbours and bays are becoming more and more similar to each other," says Johnston.
+But what helps these alien species to take root in their new found home? 
+What evolutionary advantage do they have over the natives?
+Studying polluted waters around Sydney, Johnston and team have found that exotic invaders, like the notorious red bryozoans (lace corals), thrive in copper-polluted water.
+"We've now got the first data that some of these introduced species are really highly tolerant of copper," says Johnston.
+Copper pollutes waterways from urban and industrial run-off, mining activity and sewage.
+But interestingly, copper is also the main component of anti-fouling paints that are on the bottom of ships.
+And Johnston says this is acting as a selective pressure to deliver tough pollution-adapted exotics around the world.
+This is because creatures that survive the anti-fouling paint have an advantage over the natives. 
+Copper is the key
+In laboratory experiments Johnston and team showed that exotic species from polluted waters are more tolerant of copper than native species.
+But the same exotic species living in non-polluted sites don't have the copper tolerance, says Johnston.
+"They seem to be able to switch the tolerance on and off," she says, adding that the findings apply worldwide.
+Johnston is now teaming up with the Australian Antarctic Division (AAD) to study the effect of pollution from Antarctic bases on marine organisms.
+In cleaning up pollution from previous less-environmentally conscious days the AAD has found contaminated sediments, says Johnston.
+Separately, she says the scientists have been looking at potentially invasive species and have studied alien species, taken from on the hull of the Aurora Australis research vessel.
+Lab experiments have shown that up to seven of these species can survive down to 0°C, says Johnston.
+She now wants to see if these species are invading polluted sites in Antarctica.
+
+Bomb-making ingredients could be hidden in small bottles and carried on planes. Alternatively, toiletries themselves could be used to make explosives
+Hair gels and lotions may have been banned from carry-on luggage as they could be assembled on board a plane to make a bomb, a US criminologist says.
+Professor Alfred Blumstein from Carnegie Mellon University in Pittsburgh, who helped write a government report on threats to airlines from explosives, was speaking after UK police say they had foiled a plot to blow up aircraft flying to the US.
+This prompted authorities to ban liquids, including drinks, hair gels and lotions, from carry-on baggage.
+"My hunch is that the reason they are prohibiting this stuff is that it does obviously have the potential of being assembled on board so that it doesn't look like a bomb going through the x-ray machine," says Blumstein. 
+Such mundane items as nail polish remover, disinfectants and hair colouring contain chemicals that can be combined to make an explosion and are not detectable by "sniffing" machines, which detect plastic explosives but are not used with all baggage. 
+Explosive ingredients can be concealed in bottles or other innocent-looking containers that would pass through x-ray machines. 
+That does not mean they are easy to make into bombs, cautioned Dr Neal Langerman, a San Diego consultant who is former chair of the American Chemical Society's Division of Chemical Health and Safety.
+"Many of the ingredients like acetone are household chemicals," Langerman says.
+But some kind of expertise is usually needed to buy peroxide that is concentrated enough to work in an explosive, he says.
+Bombers who attacked London Underground trains and a bus in July 2005 used homemade peroxide-based explosives carried in backpacks. 
+On-board explosives
+People have tried several times to use such easily concealed explosives on aircraft.
+UK-born Richard Reid was tackled by passengers in December 2001 while trying to detonate explosives stuffed in his shoes in an aircraft lavatory. 
+In 1994, Islamic fundamentalists set off liquid explosives on a Japan-bound Philippine Airlines plane, killing a Japanese passenger and injuring 10 others. 
+Dr Mark Ensalaco, an international terrorism expert at the University of Dayton in Ohio, says Thursday's foiled operation appears to be identical to the Japan attack. 
+"I stress identical with the explosives in liquids, which appear to be assembled on the plane," Ensalaco says.
+
+Can technology solve airport security issues? Or is a permanent ban on hand luggage the answer?
+New technology to screen passengers and hand luggage for explosives is needed, say analysts after last week's airport security alert.
+"Quite frankly, metal detectors and x-ray don't cut it," says Chris Yates, aviation security expert at Jane's information group.
+"We need to invest. We need to get money into the checkpoint. We need to reassess how we do it ... Perhaps this is the final wake-up call to actually shake the decision makers from their lethargy." 
+Current airport security typically involves a five-layered process of screening checked-in luggage, with multiple x-rays and CT scans. 
+That is too unwieldy and time-consuming to apply to passengers and their hand luggage.
+Instead travellers pass through a metal detector gateway and their bags through an x-ray machine, with a random sample also checked for explosives residue using trace particle detectors. 
+What would it take to be able to check all passengers and bags for explosives? 
+"It's something which I would imagine could only be solved with either sniffer dogs or electronic sniffers and hand searching. It's a very significant undertaking to do that at somewhere like Heathrow Airport," says David Claridge, managing director of Janusian Security Risk Management in London. 
+Jane's analyst Yates says new technology is becoming available, such as quadrupole resonance scanning developed by Australian-based QR Sciences, which uses radio waves to stimulate certain atoms such as nitrogen, present in explosives.
+Its scanner, with a traffic-light display to indicate all-clear, further investigation or danger, has already been trialled internationally, including at Manchester Airport. 
+Rolling out such technology universally would require time and a huge reallocation of investment which until now has gone into other areas, such as deployment of sky marshals on planes. 
+Liquid explosives
+An al Qaeda plot to blow up airliners with liquid explosives was uncovered as far back as 1995.
+But authorities have never previously banned people from carrying fluids, such as toiletries, onto planes as happened last week.
+Though police have given no further details, security analysts say there were indications they were concerned about militants setting off a liquid explosive such as nitroglycerine with some form of non-metal detonator, or combining otherwise harmless liquids on board a plane to produce an explosive mix. 
+The future of hand luggage
+In the meantime, Yates says he expects the current restrictions on hand baggage to continue, at least for flights into and out of the UK, possibly for months.
+He says a permanent ban on hand luggage would be untenable, not least because of the risk of theft from luggage carousels. 
+But not everyone rules out such radical solutions. 
+"I reckon the days of carry-on luggage are gone," says Maxim Worcester, managing director of Control Risks consultancy in Germany.
+"It's the easiest way of solving the problem, isn't it?"
+
+Is this embryo destined to develop into a woman with breast cancer? Image: iStockphoto)
+Australian IVF clinics are offering a test that enables parents to discard embryos that will develop into women at risk of breast cancer.
+The tests pick up mutations in the BRCA1 and BRCA2 genes, Dr Leeanda Wilton, head of the Genetic and Molecular Research Lab at Melbourne IVF, told a recent international conference in Brisbane.
+But the tests have sparked ethical concerns about whether an embryo should be destroyed on the basis of a risk factor.
+Most current tests on embryos are based on detecting those that carry a known genetic disease.
+PGD, or preimplantation genetic diagnosis, enables genetic abnormalities to be diagnosed in a very early IVF embryo before it is implanted into the mother.
+Originally tests used fluorescent in situ hybridisation (FISH) to determine an embryo's gender and detect whole chromosome disorders that may have made an IVF embryo unlikely to 'take' once implanted.
+But newer polymerase chain reaction (PCR) techniques have made it possible to test for a range of single-gene disorders, such as cystic fibrosis, haemophilia and muscular dystrophy.
+This technique can also detect mutations in the BRCA genes, which confer an estimated 65-85% risk of the carrier developing breast cancer by the age of 70.
+How is PGD done?
+A woman with a family history of breast cancer, or who carries the BRCA mutation, can ensure her baby doesn't inherit it by undergoing IVF to create an embryo and testing that embryo before implantation.
+To do this, scientists make a tiny hole into the shell around the embryo, gently remove one cell and test it.
+If a mutation is found the embryo is discarded. If no mutations are picked up it is implanted in the woman to establish a pregnancy.
+While at least three Australian clinics offer the breast cancer tests, demand doesn't yet seem to be high, although experts expect this to change.
+Dr Wilton says Melbourne IVF has the technology to test for the breast cancer mutation but hasn't yet done such tests.
+"That's predominantly because we haven't been asked to do it," she says.
+Dr David Cram, director of molecular genetic services at another large Victorian clinic, Monash IVF, says two patients have requested BRCA screening in the two or three years it's been available.
+He expects demand to grow as more young women of child-bearing age find they carry the gene.
+"Once systems are in place to identify these mutations more readily, women of a younger age will consider this option when they want to have children," he says.
+"I think we'll see some patients take up the technology in the future."
+James Marshall, PGD laboratory manager at Sydney IVF, says about three patients have asked for testing and a number clinical geneticists have inquired about it.
+"The first patient requests have only been in the last nine months," he says.
+Queensland Fertility Group hopes to be able to test for a range of single-gene conditions, probably including breast cancer, by the end of the year, says scientific director Keith Harrison.
+"Once you've got a monogenic PGD program then we'd do [all the tests] as long as the gene defect is characterised," he says.
+"But it would be an interesting one to run past the ethics committee, because when you're testing for say cystic fibrosis or Huntington's, you're discarding or destroying embryos because they actually carry a moderately lethal defect.
+"But the BRCA gene ... isn't a total guarantee you're going to get the disease."
+Ethical concerns
+Dr Wilton acknowledges there are ethical issues in testing an embryo for breast cancer risk but defends a woman's right to have the test.
+"It's not straight forward ethically, that's for sure. But I think what we see is that the patients who come for PGD certainly don't do it on a whim," she says.
+"Usually the ones who end up in PGD have usually had a very tragic history of breast cancer.
+"If there is a way that her daughters can avoid that it's very easy to understand why patients would want to take that path."
+Dr Domenico Coviello is an Italian medical geneticist and head of the Laboratory of Medical Genetics, in Milan.
+Coviello, who raised concerns about the practice at the 11th International Congress of Human Genetics earlier this month, says PGD is banned by law in Italy and other European countries including Austria and Germany.
+"Medical geneticists and doctors in general have the aim to help people and cure people ... but I am a little concerned about taking tests, especially on predisposition, and BRCA is only a risk," he says.
+
+Local maize (left) and introduced variety (right) from Baucau, East Timor's second largest city
+Looting and security threats during recent civil unrest haven't deterred an initiative that's helping East Timorese farmers increase their crop yield.
+The Australian government-funded Seeds of Life (SoL) program aims to improve crop yield and resistance to pests and disease through the use of improved varieties of five staple crops: maize, cassava, sweet potato, rice and peanuts.
+Early results have been encouraging, staff say, with a 50% increase in grain yields on research station trials and on farmers' fields.
+Months earlier, civil unrest in the capital Dili, including the looting of the SoL office by people queuing for rice, threatened to slow the program.
+"[But] nothing stops the planting of crops," says Alex Dalley, the program's research and extension officer.
+Dalley says despite a number of Timorese nationals working on the program losing family members in the violence, and other staff members being forced to move from the capital due to threats and lack of security, it is business as usual for the program.
+"[We're] working full days and farming is carrying on in the districts. Due to the good geographic spread of the program, all the staff have been able to continue their work in areas of the country which they feel comfortable in," Dalley says.
+Food insecurity is a major issue in East Timor. It affects an estimated 64% of the population, with many rural households experiencing food shortages from November to February.
+Food insecurity is partly the result of low levels of food production, a consequence of poor land and the generally low levels of technology, combined with high crop losses, both pre- and post-harvest. 
+SoL's work is a mix of research training, trialling with farmers, setting up research stations and applying social/economic research.
+
+These healthy mice were conceived using sperm from fathers that been sitting in the freezer for years
+Sperm extracted from mice and testes that have been frozen for as long as 15 years have yielded normal, healthy offspring in a study that researchers say heralds fresh hopes for bringing back extinct species.
+Frozen sperm is now preserved with cryoprotectants, substances that protect it from freezing damage. But defrosted sperm cannot always fertilise an egg.
+Researchers from Japan, the UK and Hawaii have now found that sperm can be frozen safely for much longer than previously thought, so long as it is kept in organs or whole carcasses and cooled slowly to -20&deg;C or lower. 
+They publish their findings online today in the Proceedings of the National Academy of Sciences.
+The scientists used sperm from whole mice and testes that had been frozen for between one week and 15 years and managed to fertilise eggs via microinsemination to obtain healthy offspring.
+"Many people thought that sperm integrity could be retained for several months at most ... but the sperm nucleus is stronger than we expected," says Dr Atsuo Ogura of the Japanese government-funded Riken Bioresource Centre.
+"[Sperm nucleus] is good for at least 15 years," he says, adding that offspring of the mouse that had been frozen for 15 years did not appear any different from the others. 
+Anyone can do it
+The scientists used very simple freezing methods. The mouse that was frozen whole for 15 years was merely kept in a conventional freezer at -20&deg;C, Ogura says.
+"This cryopreservation technique is probably the simplest and anyone can do it. Liquid nitrogen is not necessary. Any conventional freezer or dry ice will work very well." 
+He says this method of freezing would work for many other mammals because mammalian sperm has special DNA that "retains nucleic activity and keeps the nucleus alive". 
+"We can apply this method to many other mammals, it is very simple. Just put the testes or dead body into a freezer." 
+But he cautions that carcasses must be allowed to cool slowly, for about two to three hours to reach -20&deg;C. Sperm frozen at lower temperatures would be better preserved.
+"Degradation is minimal in liquid nitrogen [-196&deg;C]. Molecules in the cells stay still in this condition, so the degradation will be minimal," he says. 
+Hope for IVF, extinct species?
+The experiment may also have implications for freezing sperm for future cycles of IVF. 
+"This experiment proves that immotile sperm is just as good if frozen in good condition," Ogura says.
+Looking ahead, Ogura says this advance gives fresh hopes that extinct species may roam the Earth again.
+"Restoration of extinct species could be possible if male individuals are found in permafrost," he says, through injecting the sperm into eggs from females of closely related species.
+
+The new teddy is designed to recognise you, respond if you cuddle it and tell medical staff if anything's wrong
+An electronic teddy bear inspired by therapeutic companion animals could offer hospital and nursing home patients a meaningful form of treatment without the worry of allergies, bites or maintenance.
+The Huggable, designed by researchers at the Massachusetts Institute of Technology (MIT), is based on a traditional stuffed animal but is actually much more.
+It will be loaded with full-body sensors, motors, microphones, a video camera, software and wireless communication technology to produce an engaging response to humans.
+The bear is also designed to monitor the patient, alert nearby nurses when the person may need help or more intensive, long-term care and even gather information about the interaction that can be used to better understand the relationship later.
+"We are designing the Huggable to be much more than a fun, interactive robotic companion, but rather to function as a team member that works with both the patient or resident and the hospital or nursing home staff with the ultimate goal of promoting the wellbeing of the person," says Walter Dan Stiehl, a PhD candidate at MIT and the team leader for the project.
+The first Huggable prototype, which Stiehl and his team plan on finishing in the next few months, will have more than 1000 sensors beneath the fur and a soft layer of silicone skin.
+The temperature, force, and electric field sensors will work together to distinguish the presence of a human, pick up some of the physiological signs of the patient's condition and discern whether the person is petting, scratching, slapping or hugging the bear.
+Cameras in the eyes will be used to scan the room, while face recognition technology in the robot's computer will help the Huggable detect familiar people. Microphones in the ears will allow it to hear and face the direction of a sound.
+Senses pain then acts on it
+Stiehl and his team are programming the bear to exhibit different behaviours based on what it sees, hears and senses.
+If it sees someone familiar, it can raise its eyebrows in an expressive greeting and say hello. While being rocked it will wear an expression of happiness and when being cuddled, it will nuzzle into the person.
+But the concept for the Huggable does not focus on simply providing companionship.
+The technology will be designed to work with a separate computer located at a nurse's station, where video, audio, or other data collected by the bear's sensors could alert caregivers in times of potential crisis.
+For example, if a patient is hugging the bear and then it falls to the floor, that action could prompt a nurse to check that all's well.
+Long-term care
+The Huggable can also collect information about the patient-bear interaction over a long period of time.
+Any changes, such as the patient suddenly becoming aggressive or showing far less activity, may offer subtle indications of more serious problems.
+"We've not adequately used technology to help older people and this is one potential in which we could do that," says Rebecca Johnson, professor of aged care nursing at the University of Missouri in Columbia.
+Stiehl's group is finalising the first prototype and hopes to have at least 10, if not 20, Huggables available for pilot trials in about a year's time.
+
+The whale had enourmous eyes and, unlike today's baleen whales, teeth to rip apart prey
+A bizarre whale fossil found on a beach in southern Australia suggests that baleen whales, the filter-feeding gentle giants of the sea, were not always gentle, or giants, a researcher says.
+Erich Fitzgerald, a PhD student of Monash University in Melbourne and a research associate at Museum Victoria, describes the 25 million year old discovery in the latest issue of the journal Proceedings of the Royal Society B.
+The fossil, which includes a complete skull of a whale and other bones, was found in the late 1990s by teenage surfer Staumn Hunder, Fitzgerald explains.
+"Luckily for science, he saw these dark brown slithers of fossilised bone," protruding from a boulder on a beach near the town of Jan Juc in coastal Victoria.
+Hunder and his father delivered the boulder to Monash University more than six years ago, but little long-term research was done on it until Fitzgerald began studying it in 2003.
+"Even when I'd only completed half of it, it was pretty obvious this was groundbreaking," he says.
+Fitzgerald found that the fossil had specific features in the facial region and the base of the skull that marked it as a member of the baleen whale group, which today includes the enormous blue whale.
+But unlike modern baleen whales, which eat by filtering tiny krill and plankton from water, the fossil whale had teeth. It also had enormous eyes.
+"This animal was capturing big, single prey, which is unusual for a baleen whale," Fitzgerald says. "It used the front of its mouth to grip its prey and rip it apart."
+He says it was impossible to fit the fossil whale into existing branches of the evolutionary tree based on its shape, size and characteristics.
+For one thing, it was only about 3.5 metres long, roughly the same size as a bottlenose dolphin.
+The smallest living baleen whale, the pygmy right whale, is normally around 7 metres long, Fitzgerald says.
+"This is something completely new. This was an entirely new family, which is a rare occurrence."
+This new family of small, highly predatory, toothed baleen whales has been named in honour of the town of Jan Juc and its discoverer Staumn Hunder. It is called Janjucetus hunderi.
+"This essentially opens up a window on what the earliest baleen whales were like," Fitzgerald says.
+"It tells us that they were truly bizarre, and living in ways completely unlike any baleen whales that have existed over the past 20 million years."
+
+You want me to do what?
+People whose cheeks turn red at the thought of speaking to a stranger have similar blood flow to everyone else.
+It's just that their blushing takes longer to subside so it's more obvious to them and others, Australian research suggests.
+A team of researchers led by Professor Peter Drummond from Murdoch University in Western Australia rated facial blood flow in people frightened of blushing as they performed everyday, but potentially squirm-worthy tasks.
+These included speaking to a stranger, giving a speech and listening to the taped speech afterwards.
+The researchers then compared the results with a group of people who weren't frightened of blushing who performed the same tasks.
+They found embarrassment and self-reported blushing intensity was greater in the fear-of-blushing group than in the control group throughout the experiment.
+While increases in facial blood flow were similar in the two groups during each task, blushing took longer to subside in the fear-of-blushing group than in controls.
+The researchers report online in the journal Behaviour Research and Therapy how this resulted in an incremental increase in facial blood flow over the course of the experiment.
+Drummond says the differences in blushing behaviour could come down to a number of factors. 
+"It may be that there is a difference in the way the facial blood vessels respond during social encounters [in fearful blushers] which prolongs the increase in facial blood flow; or a difference in the way people cope in slightly stressful situations," he says. 
+"Or it may be that people who are frightened of blushing are simply more anxious than those who aren't, and this anxiety then persists for some time afterwards, so it takes them a little longer to recover and get back to normal."
+It may also be that because the blush response lingers longer there's more opportunity for the person and others to notice it, he says.
+What can you do about it?
+Either way, Drummond says the research has its silver lining for people worried about blushing.
+"During these social encounters they are blushing no more strongly or more frequently ... than people who don't feel they blush very much. They just take longer to recover."
+And that, according to Drummond, could simply be the result of the blusher's thought process.
+"[They're] going over all the possible ways that they could have embarrassed themselves during the social encounter," he says.
+If the research helps people come to terms with that it could help them lose their fear of blushing, he says.
+
+The terrorism alert caused chaos at Heathrow Airport last week. But could new security technology prevent a repeat performance?
+No matter how sophisticated airport security technology becomes, it will probably never remove the need for sniffer dogs and bag searches, experts say.
+The alleged foiled terrorist plot that affected flights between the UK and US  last week has led to calls for newer, smarter security technology. 
+Devices on the horizon include insect-based sensors, wallpaper that sniffs out explosives as you walk past and smart closed-circuit TV that can pick a suspect out from a crowd or tell if you've left a bomb under a seat.
+But Martin Cebis, whose company will present its all-in-one chemical sensing and surveillance system at an international military technology conference in the US next week, says would-be terrorists will probably always be one step ahead of technology.
+"Ultimately you're dealing with human ingenuity [and] you're fighting a moving target and need to be able to adapt," says Cebis, chief executive officer of Western Australia's Embedded Technologies.
+"I think you'll still need searching and those kinds of things to occur."
+Cebis is also among a number of speakers who will brief security advisors and researchers in Canberra on the latest developments today.
+Chemical sensing
+One of the emerging areas of security, particularly in light of the alleged plot to carry liquid explosives onto planes, is in chemical sensing.
+Associate Professor Adam McCluskey of the University of Newcastle is an Australian researcher developing chemical sensors based on drug design technology.
+The sensors are can be "screen printed" onto fabrics, paper, plastics and even wallpaper.
+"It's basically a synthetic antibody," he says.
+"We're applying drug design technology to generate polymeric scaffolds that specifically recognise the shape and electronics of the targeted molecule."
+The technique has been used to identify cocaine and heroin and is being developed to pick up chemicals like TNT and triacetone triperoxide, the chemical used in last year's London Underground bombings.
+"Instead of metal detectors we would have a bank of these sensors sucking the vapours off as you walk through," he says.
+He says while sniffer dogs will still be able to go places electronic noses can't, sensing technology will be better able to detect specific substances.
+Dr Michael Borgas, is an atmospheric scientist at CSIRO, which is developing an electronic nose to detect chemicals. 
+He says the future of airport chemical sensing lies in miniaturised devices.
+Researchers at CSIRO are also looking to insects like fruit flies for inspiration.
+"If you can understand how insects sense and act upon various volatile chemicals you'd hopefully be able to mimic that with electronic devices," he says.
+"What you want is a hand-held device that can suck in tiny bits of air and detect the molecules that are in that air. In airports you'd just stick it in a [passenger's] bag."
+Smart surveillance
+Cebis says it will take more than high-tech chemical sensors, no matter how sensitive and discriminating they are.
+"It's fine to have sensors all over the place but you've got to be able to make intelligent decisions," he says.
+"The research challenge is to make cheap, sensitive, ubiquitous sensors coupled with smart surveillance technology."
+Cebis says closed-circuit TV will eventually be replaced by "smart" digital video technology that uses biometric identification and motion recognition to hone in on specific individuals and behaviour.
+"They look at a scene and if there's no motion they don't film anything," he says.
+"Or a person may wander into a scene, deposit something and then move away. The fact that something was moving and now isn't [will be picked up]."
+Ting Shan of National ICT Australia (NICTA) will outline advances in face recognition technology at a security technology conference in Canberra next week.
+Shan says new face recognition algorithms have been developed by NICTA and University of Queensland that aren't befuddled by lighting, expression or angle of the face.
+"It can synthesise a realistic frontal face image," he says.
+Impact of a new security environment
+Borgas says while the events in the UK have highlighted advances in security technology, he doubts they will be implemented overnight.
+McCluskey hopes it will give governments an impetus to provide the research and development funds to allow some of the more promising ideas to bear fruit.
+"Sometimes it takes an event of this nature to provide a significantly high profile and the government willing to take a chance on the technology," he says.
+Cebis say all the technology in the world will never completely replace the most humble of checks.
+"But whether they need to be as intrusive and time consuming as they currently are depends on the technology," he says.
+
+Long before Gondwana existed it would have been possible to surf in Central Australia, in areas that now look like this
+Northern Australia was once a separate land mass to the rest of the continent and it crashed into central Australia, wedging underneath it, researchers say.
+Kate Selway, a geophysicist and PhD student at the University of Adelaide, and colleagues, have been studying the collision that is estimated to have happened 1.64 billion years ago.
+"If you looked south from Alice Springs before that time, you would have seen an ocean," Selway says.
+Most scientists have long suspected that the Australian continent we know today is formed from pieces of land that were previously attached to other continents.
+For example, comparison of different rock types, ages and chemistry suggest that, long before eastern Australia existed, northern, western and central Australia were all discrete landmasses, says Selway.
+When they collided, some time less than two billion years ago, mountains were formed, which have long since eroded away, she says.
+But Selway says no one has really known where exactly the boundaries of these separate plates were and how exactly they collided.
+"People had theories that these boundaries are there but they've been hard to see because they're largely covered by dirt and sediment," she says.
+Which edge under which?
+When continents collide, the edge of one can wedge under the other in a process called subduction.
+The prevailing theory has been that central Australia subducted under northern Australia, says Selway.
+But she says there was never much data to back this up.
+She and colleagues used a technique called magnetotellurics to peer hundreds of kilometres beneath the Earth's surface in the vicinity of the presumed boundary between northern and central Australia, just south of Alice Springs.
+The technique relies on the fact that the Earth's magnetic field causes current to flow through rocks.
+It measures the strength of the current as it changes with the electrical conductivity of different rock types.
+Selway and colleagues plotted the changing profile of electrical conductivity along a 380 kilometre track north of the Northern Territory-South Australian border, down to a depth of 200 kilometres.
+The profile shows that the northern plate was more conductive than the central one. And it also shows that the northern plate is wedged under the central one, and not the other way around.
+Because boundaries between plates can be places where minerals concentrate, this kind of "big picture geology" helps the narrow down places to explore for minerals, says Selway.
+Some of the research, which was funded by the Northern Territory Geological Survey, was reported in Geophysical Research Letters earlier this year. The rest has been submitted to the journal Geology.
+Selway is one of 16 young scientists presenting their research to the public for the first time under the Fresh Science program.
+
+The discovery of Xena sparked the debate about the definition of a planet. Now the world's astronomers are set to decide on which celestial body we invite into the planetary club
+The solar system may soon be home to a dozen planets, with three new additions to the club and more to come, if astronomers approve a new definition of a planet.
+The proposal before the 26th general assembly of the International Astronomical Union (IAU) in Prague distinguishes between planets and smaller celestial bodies such as comets and asteroids. 
+It leaves Pluto's status as a planet intact, but modified. 
+The proposed new definition of a planet would result in a 12-planet solar system with eight classical planets; three plutons, a new growing category of Pluto-like objects, including Pluto, 2003 UB313 (dubbed Xena) and Charon; and Ceres, a former asteroid.
+Powerful new telescopes that have discovered large objects in the outer regions of the solar system present a challenge to the historically based definition of a planet, which comes from the Greek word meaning wanderer. 
+"Recent new discoveries have been made of objects in the outer regions of our solar system that have sizes comparable to and larger than Pluto," says IAU president Professor Ron Ekers. 
+"These discoveries have rightfully called into question whether or not they should be considered as new planets." 
+The planetary debate blasted off in July 2005 when a US team of astronomers announced that Pluto was much smaller than an enigmatic object, 2003 UB313, which its discoverers said was the solar system's 10th planet. 
+UB313, found some 15 billion kilometres from Earth, ignited a huge row as Pluto's defenders said UB313 was not a planet, just a rock, or KBO, a Kuiper belt object.
+A KBO is one of about 100,000 pieces of icy, primeval debris encircling the Sun on the outskirts of the solar system.
+"Had astronomers realised in 1930 that Pluto was smaller than our Moon and with a mass well under 1% that of the Earth, perhaps some special designation would have been devised for it," say Professor Owen Gingerich, head of the IAU committee that came up with the proposed definition.
+Since it was founded in 1919, the IAU has been the arbiter in astronomical debates and after two years of work a committee has come up with a new planet definition to present to some 2500 astronomers gathered in the Czech capital. 
+According to the draft definition, a planet must orbit a star, while not being itself a star, and it must be massive enough for its own gravity to pull it into a nearly spherical shape. 
+"Our goal was to find a scientific basis for a new definition of planet and we chose gravity as the determining factor. Nature decides whether or not an object is a planet," says Professor Richard Binzel, a member of the defining committee.
+That puts about a dozen "candidate planets" on the IAU watchlist, which means even more planets could be named in the future. 
+If the current proposal is passed by the IAU assembly, the solar system would consist of the planets Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Charon and 2003 UB313 (a 'real' name to be chosen later).
+The new plutons are distinguished from classical planets in that they reside in orbits around the Sun that take longer than 200 years to complete, meaning they are in orbit beyond Neptune.
+The draft planet definition will be discussed and refined during the meeting and put up for a vote on 24 August.
+
+Our Moon may qualify for the title of 'planet' if it continues to move away from the Earth
+The proposed new definition of a planet has got scientists talking, some saying it means even our Moon could one day be labelled a planet.
+Astronomer Dr Charles Lineweaver of the  Australian National University says he is generally in favour of the draft International Astronomical Union (IAU) definition, but it has some potential problems.
+"According to the new definition of planets, our Moon ... will become a planet in the future," says Lineweaver.
+Under the draft definition, which astronomers will vote on next week in Prague, a planet must orbit a star, while not being itself a star, and it must be massive enough for its own gravity to pull it into a nearly spherical shape.
+Under this definition, Charon would no longer be a satellite of Pluto. Rather both would qualify as planets, of the pluton type.
+Central to this double-planet system is a common centre of gravity, or barycentre, that exists in free space above the surface of Pluto.
+By contrast, our Moon would remain a satellite under the new definition because the barycentre of the system is located below the Earth's surface.
+But Lineweaver says as the Moon is moving further away from the Earth, this means the barycentre will one day be above Earth's surface.
+"The Moon will have to be about 40% further away than it is now for it to become a planet," he says.
+"Based on an extrapolation of the current recession of the Moon, this will happen in about 5 billion plus or minus 1 billion years."
+
+Dust devils, or willy willies, can't be explained by wind alone, scientists say
+It's not just wind that raises sand and dust devils, say physicists, powerful electrical fields created by wind, sand and dust also levitate more dust into the air.
+The discovery could have implications for global climate modelling and even help explain what makes Mars such a dusty world.
+More than 100,000 volts per metre of natural, 'static' electricity have been measured in desert dust storms and the mini-tornado-like dust devils or willy willies. 
+Now, under laboratory conditions, Jasper Kok, a graduate student at the University of Michigan in Ann Arbor, has reproduced the electrical fields found near the ground in desert wind storms and shown that they can also lift sand grains.
+"We were very surprised," says Kok of the power of electrical fields to raise dust and sand.
+He and his faculty advisor Associate Professor Nilton Renno are publishing their results in a coming edition of Geophysical Research Letters.
+The process starts with a little dry wind in a dusty, arid place that kicks up small dust grains so they collide with larger sand grains, Kok explains.
+When this happens the smaller grains steal electrons from the larger grains, giving the smaller grains a negative charge and the larger grains a positive charge.
+"It's very similar to rubbing your feet on a carpet to become charged," says Kok. In that case you are the smaller grain and the carpet is the larger grain.
+Next, the negatively charged smaller grains are lifted above the ground by breeze, creating a negatively charged region in the air above the positively charged ground. That separation of charges is an electrical field.
+Once that field is in place, as Kok shows in the lab, more grains can be lifted up by the electrical forces, making for even dustier conditions than wind speed alone could create.
+The phenomenon could have significant impacts on how much dust gets into the air worldwide, which means it's a matter that global climate modellers need to study more closely, says Dr Ron Miller of the NASA Goddard Institute for Space Studies in New York.
+The many properties of dust
+Dust is an 'aerosol', which can reflect sunlight back into space and cool the Earth's surface, as well as just influence the quality of the air.
+"For a given wind that's already kicking up dust, you'd get more dust," says Miller.
+It could also affect areas downwind of a dust source, he says, by transporting the electrical fields to other areas and also more readily mobilising dust there.
+That matters a lot in places like China, where dust from the northern deserts whips south across industrial regions, picking up a lot of pollutants that can then be blown east as far as the European Alps.
+Dust on Mars
+Electrical fields may help explain how dust gets around on Mars, says Renno.
+"On Mars the wind required to lift dust from the surface is very large," he says, because the atmosphere of Mars is very thin. 
+"Winds of the magnitude required have never been measured, but there's dust everywhere."
+Kok says he's already working on a new laboratory experiment with Mars-like conditions to see if electrical fields may be at work on the Red Planet.
+
+This doesn't smell familiar. I think I'm lost
+Italian researchers may have solved the puzzle of what makes homing pigeons such legendary navigators - they simply follow their noses.
+In a real-life homing experiment, Dr Anna Gagliardo of the University of Pisa and colleagues tested the birds' magnetic sensing and olfactory systems to establish how they make their extraordinary navigations across hundreds of kilometres.
+The research, published in the 1 August issue of the Journal of Experimental Biology, followed a 2004 laboratory study by Dr Cordula Mora and colleagues from the University of Auckland, New Zealand.
+In this research, Mora conditioned pigeons to detect an anomaly in a magnetic field.
+She showed that pigeons detected a magnetic stimulus in their upper beaks by using the ophthalmic branch of the trigeminal nerve, the largest cranial nerve.
+The 2004 study reinforced the theory that homing pigeons navigate by using tiny magnetic particles in their beaks to map changes in the Earth's magnetic fields.
+But Gagliardo says they don't always use this method to find their way.
+"They do have the ability to detect magnetic fields, but this doesn't mean they use it to navigate," he says.
+To test how much the birds use this sense, Gagliardo cut a section of the olfactory nerve in 24 homing pigeons and a section of the opththalmic branch of the trigeminal nerve in another 24.
+A third group of 24 birds underwent sham operations and served as a control group.
+Gagliardo then released the three different groups of inexperienced homing pigeons about 50 kilometres from their loft.
+All but one of the birds with the severed trigeminal nerve were home the next day, suggesting that the ability to detect magnetic fields is not used to navigate. Among the control group, only one pigeon was lost.
+Meanwhile, most of the birds deprived of their sense of smell were totally lost. Only four made it home.
+A patchwork of smells
+According to Gagliardo, homing pigeons create odour maps of the areas they fly over and use them to navigate, basically reading landscapes as a patchwork of odours.
+"In my view this study certainly ends the debate for homing pigeons," says Professor Verner Bingman, a behavioural neuroscientist at Bowling Green State University, Ohio.
+"It is now as clear as can be that information about the spatial variation in atmospheric odours detected by the olfactory nerve is the primary sensory basis of the homing pigeon navigational map."
+But Associate Professor Martin Wild, a neurobiologist at the University of Auckland who performed the surgical procedures for both the Mora and Gagliardo studies, cautions that the Pisa experiment should not be considered the definitive study on how pigeons navigate.
+"Nature does not yield up her secrets so easily," says Wild. "The birds will use whatever sensory cues are available at the time. Showing that pigeons actually use a magnetic sense is extraordinarily difficult."
+Wild further points out that homing pigeons are thought to have two magnetic senses, not just one. One is in the beak and the other in the photoreceptors of the eye.
+"Perhaps both are used under different circumstances," he says.
+
+Could the hobbit really be one of us after all?
+A new paper has inflamed the debate over the hobbit's origins, with one researcher criticising the scientific journal that published the research.
+A paper in today's issue of the Proceedings of the National Academy of Science (PNAS) is the second this year to conclude that the hobbit is just a sick human.
+Indonesian researcher Professor Teuku Jacob, from Gadjah Mada University, and an international team argue that the hobbit is a microcephalic pygmy rather than a new species of hominid.
+"All the odd things about it aren't things which indicate another species," says co-author and anatomist Dr Alan Thorne, a visiting fellow at the Australian National University.
+"It happens to be an individual [human] with major, probably genetic, deformities."
+Thorne says the team reached its conclusions by comparing 140 anatomical features of the hobbit specimens with those of human specimens.
+He says none of these features were outside the normal range for humans, in particular Australomelanesians, which is his research speciality.
+Thorne says previous comparisons of the hobbit had been with inappropriate western European populations.
+Study and journal criticised
+But two of the original Australian discoverers of the hobbit, Professor Peter Brown and Professor Mike Morwood from the University of New England, have lashed out at the researchers, rejecting arguments put forward in the latest paper.
+Brown also criticises the journal itself for publishing the research.
+Brown says the paper's conclusions are "unsupported by any published evidence" and that the paper makes "misleading comments" about previously published papers.
+Australian National University taxonomist Professor Colin Groves, who was not involved in the research, also rejects the PNAS paper.
+"Most of their claims of pathology are not substantial," says Groves, who has a paper due out in the Journal of Human Evolution rejecting the microcephaly theory. 
+Unethical conduct?
+Brown says putting aside the scientific argument itself, PNAS should not have published the research because of what he says is the research team's "unethical scientific practice", a claim the authors reject.
+One of the sticking points is whether correct permission was obtained to study the precious hobbit bones.
+The PNAS article states that the researchers were permitted to study the hobbit materials in accordance with a research agreement between the Indonesian National Research Centre of Archaeology and the University of New England.
+But Brown and Morwood say the researchers breached the agreement by removing the material from the archaeology centre in Jakarta before the Australian researchers had managed to complete their analysis.
+It was removed without the agreement of both parties and without any conditions for proper credit, says Morwood.
+Brown is also critical that Thorne had a flight to Indonesia paid for by an Australian TV company to examine the material.
+But Thorne says there's nothing improper about this.
+"The fact that my fares were paid by a television company is simply a function of the fact that I'm now retired and someone wants to pay my airfares I'm not going to knock it back," he says.
+Brown also says the material was damaged beyond repair while being studied.
+Thorne says he didn't see the material after it was returned from Jacob's lab but when he saw it, it was in fine condition.
+Scientists behaving badly or a misunderstanding?
+Overall, Brown thinks the conduct of the PNAS authors amounts to bad behaviour.
+"I can't think of a more extreme example of unethical scientific practice," says Brown, "For PNAS to reward their behaviour casts aspersions on the journal."
+Thorne says he doesn't understand the claim. He says he was invited to look at the material by Jacob, whom Thorne had met many times over his decades of research in Indonesia. 
+"There was nothing unethical about that at all," he says, adding that the PNAS paper had five referees, including experts in anatomy, pathology, growth and development.
+Journal stands by its paper
+A spokesperson for the journal confirms the article was peer-reviewed prior to submission and also by a member of the PNAS editorial board before being accepted for publication. 
+PNAS declined to comment on Brown's allegations, instead referring ABC Science Online's questions to the study authors.
+
+The star AE Aurigae surrounded by dust, which may be hiding deuterium and complicating astronomers' efforts to study star and galaxy formation
+A six-year study of a primordial element created just after the birth of the universe may force scientists to revise theories about how stars and galaxies formed.
+Using a telescope sensitive to far ultraviolet light, astronomers have discovered that there is much more deuterium, a heavy form of hydrogen created minutes after the Big Bang, than expected.
+"Our models of the chemical evolution of the Milky Way will have to be revised significantly," says astrophysicist Professor Jeffrey Linsky with the University of Colorado at Boulder.
+All the deuterium that ever existed was believed to have been forged within a few minutes of the Big Bang 13.7 billion years ago. 
+Deuterium is a heavy version of regular hydrogen, the lightest and most abundant element. But its nucleus harbours a neutron in addition to the normal proton, so it is twice hydrogen's mass.
+Because stars consume deuterium and there is no known process to create more, the isotope serves as a tracer for star formation and galaxy creation throughout time.
+Scientists thought they knew how much deuterium there was, figuring about one-third of the original deuterium was remaining.
+Not so, according to scientists using data from the Far Ultraviolet Spectroscopic Explorer, or FUSE.
+Launched in 1999, the FUSE telescope breaks light into component wavelengths so scientists can determine which chemicals and other phenomena the beams might have passed through before striking the observatory's instruments.
+The team provides the first hard evidence that deuterium can attach to interstellar dust grains, as well as exist as a free-floating gas.
+The finding explains why deuterium is not spread evenly throughout the galaxy, but instead appears in clumps.
+Solving one puzzle, however, laid the groundwork for a far thornier question. In adding up the amount of deuterium, whether free-flying or bound to dust, there was far more than expected.
+"Since the 1970s, we have been unable to explain why deuterium levels vary all over the place," Linsky says. "The answer we found is as unsettling as it is exciting."
+FUSE found that the present-day deuterium abundance is less than 15% below the primordial values, rather than about 33%.
+"This implies that either significantly less material has been converted to helium and heavier elements in stars or that much more primordial gas has rained down onto the galaxy over its lifetime than had been thought," says Linsky.
+Associate Professor Brian Fields, with the University of Illinois in Urbana says:
+"FUSE has solved the mystery about why the deuterium is where it is. Now scientists need to try to explain why there is so much of it."
+
+A relative of this ancient marine organism used to dig through the mud, forming a network of tunnels
+Trilobites, the extinct marine creatures famous to fossil-hunters everywhere, may have once done digging of their own, say UK and Swedish researchers.
+Rocks found in a Swedish limestone quarry contain the remains of trilobites inside networks of tunnels, which appear to have been subsurface thoroughfares for the little bug-like organisms.
+"It's very rare to find a trilobite in a burrow," says Amherst College's Associate Professor Whitey Hagadorn, an expert on tracks, burrows and other 'trace' fossils that can give important clues to a long-lost species' behaviour and environment.
+There's only one other such fossil known, he says, and even that one doesn't show evidence that the tunnels were much more than single-use, one-way streets that collapsed after the animals made their way through the muck.
+"The fact that they form open networks, that is new and different," says Hagadorn.
+Such sand-filled tunnels are common in the fossil record, he says, and have generally been attributed to soft-bodied animals that left behind no hard parts.
+But in recent years, palaeontologists have begun to suspect that trilobites may have also done some digging.
+Finding trilobites inside tunnel remains in Sweden's 465-million-year-old Holen limestone is, therefore, a fitting but unexpected hint about how the ubiquitous creatures fit into the Palaeozoic ocean ecosystem.
+Dr Lesley Cherns of Cardiff University says these particular fossils were found by accident.
+"We sat down to lunch and I noticed that there were trilobites in these burrows," says Cherns, who co-authored a paper in this month's issue of the journal Geology.
+A life underground
+The trilobites were probably killed by something like a sudden upwelling of oxygen-poor water or some other quick and deadly event, Cherns explains.
+The tunnels were then soon buried by a thick layer of mud that sealed them off from scavengers and helped to preserve the evidence.
+No-one is quite sure what the trilobites were doing underground.
+They could have been hiding from the nautilus-like predators that cruised the Palaeozoic oceans, says Cherns.
+Or they may have used the water flowing through the tunnels to help oxygenate their gills, like some modern lobsters do, she says.
+Hagadorn has other explanations. "They could have been going down to eat, reproduce, hide ... who knows?
+"Hopefully this will motivate people to go out and look for more of these."
+That could eventually answer some of those questions, he says.
+
+Can terrorist tendencies become hardwired into the brain?
+Neuroscience can be a weapon against terrorism, says a leading brain scientist who is investigating the neurology of belief.
+Professor Susan Greenfield, director of the Royal Institution of Great Britain, says there is no such thing as a brain centre for terrorism.
+But she says that understanding the neurology of belief, identity and risk can inform the way countries respond to terrorist threats.
+"As yet no one has started looking at the neuroscience of terrorism [but] neuroscience is really in the foothills of this very important question," she says.
+Greenfield says the brain becomes individualised by the way connections between brain cells form, mainly in the first 18 years of life.
+Experiences during this time leave a mark on the brain, essentially hardwiring the way we perceive and respond to our world.
+Embedding belief
+Greenfield and colleagues at the Oxford Centre for Science of the Mind, which she directs, are investigating how belief is laid down in the brain.
+This goes to the heart of terrorism, she says, which is basically a set of tactics founded on a belief system.
+She says belief becomes embedded in the brain either through one single, significant event or through constant repetition, such as prayer or rituals, rather than evidence-based deduction.
+Once adopted, belief is very difficult to shake, although the use of cognitive therapy to treat depression shows that it is possible to 'rewire' the brain, Greenfield says.
+"Yes you can rearrange people's connections even in maturity so that they see the world in a different way," she says.
+Risky business
+Understanding risk is also a key factor in understanding what goes on in the mind of a terrorist, she says.
+Greenfield suggests the high integration of technology in our lives is producing a generation more reckless than previous ones.
+She says the instant gratification of technology prioritises experience above the consequences of our experiences, producing an "experientially biased" society.
+"If you going to have the techno world driving moment-to-moment experiences over learning and thought, then it would follow that the next generation will be more reckless and prone to risk," she says.
+Associate Professor Robert Heath, a psychologist and risk management consultant at the University of South Australia, says terrorists are both born and made.
+He says terrorists have a psychological predisposition to violence and typically score highly on psychotism, neuroticism and sociopathology.
+But they also need a 'trigger point'.
+"You need to have the disposition but you also need to have a belief set getting implanted in your head ... you also need to have a referent group that's a very strong influence," he says.
+How do we respond to terrorism?
+Greenfield says studying the brain can also shed light on how the general population responds to perceived threats.
+"What does it do to us as a society?" she says.
+She says studies in lab rats show that the best way to induce neurosis is to engender a sense of perpetual threat without a way of avoiding it.
+"One of the hardest things for a human is to be told that you're in danger and not be allowed a way out or seen any means by which you can take evasive action," she says.
+"So is it actually productive for governments to tell people 'you're in a high state of security' if you're not allowing a compensatory action."
+
+The turtles are an important source of protein for Aboriginal people and children are taught to hunt them from an early age
+Feral pigs are threatening the northern snake-necked turtle population in Arnhem Land to the point where the species could become extinct in some areas, Australian researchers predict.
+In a single experiment, feral pigs killed 96% of radio-tracked turtles in a monitored area within a three-month period.
+"They dig them up like truffles," says PhD candidate Damien Fordham, of the University of Canberra, whose research will be published in the journal Biological Conservation.
+Fordham says while the turtles are found across northern Australia, the consequences of extinction for the local Indigenous population would be "extreme".
+Northern snake-necked turtles have traditionally provided an important seasonal source of protein for Indigenous communities in Arnhem Land.
+Not only would Indigenous communities lose a valuable source of bush tucker, but with it the strong cultural ties they have with the turtle.
+Fordham and colleagues mounted tiny radio tracking devices to the shells of 40 snake-necked turtles around waterholes in Indigenous land around Maningrida, 450 kilometres east of Darwin.
+Turtles aestivate, or dig themselves into the mud, to escape heat and lack of water during the late dry season, anywhere between August to December.
+Of the 28 recorded turtle deaths during the 12-week period, 27 were attributed to feral pigs.
+Researchers believe feral pigs could have stumbled upon, and then eaten, some of the turtles while they were rooting around billabongs in search of morsels such as water chestnut.
+But it was clear that in 11 of 27 turtle deaths the pigs had specifically located and dug them up.
+Generally, pigs make a huge mess at they root around looking for food, but researchers noted relatively undisturbed areas around the 11 turtle deaths, indicating a direct 'hit'.
+"This is disturbing as it indicates that pigs actively seek out and prey on aestivating turtles," Fordham says.
+The researchers predict more turtles will die as the feral pig population increases.
+Mathematical modelling of how many turtles survive in the year of the study, if carried across all years, could led to distinction of the turtles in the region, the researchers note.
+Researchers say the turtle's best hope for survival is a few years of good rainfall, when pig predation rates are low.
+Fordham would also like to see government funding to 'fence in' turtle-rich areas.
+
+The Bullet Cluster, shown here, was formed after two large clusters of galaxies collided, the most energetic event since the Big Bang
+Astronomers have announced the first direct evidence of dark matter, although they still have only an inkling of what the elusive stuff is made of.
+The unprecedented observations come from careful weighing of gas and stars flung about in the most violent and massive collision in the known universe.
+It's a tiff between two clusters of galaxies in what's collectively called the Bullet Cluster, which has caused stars and dark matter from different galaxies to tear past each other while the more widely distributed interstellar gases collide and slow.
+"All the matter in a typical galaxy occupies the same space," says astrophysicist Dr Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics.
+"In this case the gas and galaxies are separated in space. Galaxies flew through each other but their gas clouds didn't so easily."
+Visualise, for instance, a cosmic million-kilometre per hour collision between two vast dollops of porridge with raisins in it. 
+The raisins would represent the stars and dark matter, and the oats the gases.
+The raisins would shoot through with few direct raisin-on-raisin hits, while the oats would get stuck in a patch in the middle.
+The result is different patches of space: one with lots of hot colliding gas and two others on either side with all the dark matter and stars in visible galaxies.
+The astrophysicists know the visible stars still have the dark matter with them because they weighed the mass in the starry patches by measuring how those patches bend the light from far more distant objects. The more a starry region bends light, the more massive it is.
+In this case, the starry areas in the colliding clusters have far more mass than can be accounted for by visible stars or by interstellar gases, since the stars left the gases behind. The only thing left to explain it is dark matter.
+"This proves in a direct and simple way that dark matter exists," says Markevitch.
+Suite of telescopes
+The discovery was made using a suite of observations from the orbiting Hubble Space Telescope and Chandra X-ray Observatory, along with the ground-based European Southern Observatory Very Large Telescope and the Magellan Telescope.
+A paper on the discovery will be published in the Astrophysical Journal Letters, a journal of the American Astronomical Society.
+Until now the existence of dark matter was inferred by the fact that galaxies have only one-fifth of the visible matter needed to create the gravity that keeps them intact.
+So the rest must be invisible to telescopes, or 'dark'.
+The observations of the Bullet Cluster, officially known as galaxy cluster 1E0657-56, do not explain what dark matter is. 
+But they do provide one solid little hint, says Dr Douglas Clowe, a researcher at the University of Arizona in Tucson.
+"We can place some constraints on dark matter particles," he says.
+Clues to what dark matter's made from
+It appears that dark matter particles, whatever they are, behave more like the raisins than the oats; they are either widely spaced, like stars, or have some other way of avoiding collisions with each other.
+It's a small clue, says Clowe, but seeing it play out in the Bullet Cluster makes it an unusually solid clue for what's so far proven to be the most mysterious stuff in the universe.
+"The great news about this is that it shows once and for all that dark matter exists," says physicist Assistant Professor Sean Carroll of the University of Chicago.
+And that means, he says, there's less need to tweak Einstein's laws of gravitation to explain what's seen in galaxies.
+
+Chocolate, citrus or stinky? Researchers are identifying the fungi that give regional varieties of coffee their distinctive taste
+Fungi are the secret to tasty coffee, says a Brazilian researcher who is the first to identify the moulds that give coffee its distinctive range of flavours and aromas.
+Dr Martha Taniwaki of Brazil's Institute of Food Technology presented her research at the International Mycological Conference in Cairns this week.
+Taniwaki says while the characteristics of the bean partly determine taste and aroma, naturally occurring fungi also put the zing in your favourite brew.
+"We are doing a project to correlate the presence of certain species of fungi in coffee with coffee flavour," she says.
+The research team collected raw coffee beans from farms in Sao Paulo and Minas Gerais in Brazil, disinfected them, incubated them for seven days, and isolated the fungi.
+Then the team got down to the pleasant part of the experiment. They roasted, ground, brewed and drank the raw samples, rating them for body, aroma, acidity, bitterness, astringency and sweetness.
+Some of the flavours associated with moulds included floral, citric, caramel, chocolate and toast.
+The fungi occur naturally inside the coffee been and are associated with regional characteristics caused by soil, climate and humidity.
+While the pleasant taste-producing fungi are not harmful to health, others can be toxic, and these often produce rancid, stinky, smoky, woody or fermented bouquets.
+Tanawaki says her research is currently focused on isolating the various fungi and how they are metabolised.
+But it may be possible to use the knowledge to produce ranges of coffee with a particular flavour, potentially complementing the traditional bottles of vanilla or hazelnut flavourings found at your local cafe.
+"We can encourage the good fungi to grow and use it to produce good flavours, like wine or other food like cheese where you use mould or yeast to ... give a special flavour," she says.
+Professor Paul Gadek, an Australian plant molecular biologist and head of tropical plant sciences at James Cook University, says Taniwaki's research has implications for Australia, where coffee is a growth industry.
+He says it would be interesting to find out which species of fungi are found in Australian coffee beans.
+"What are the characteristics that we can grow regionally to generate distinctive flavours?"
+
+Researchers can now test the effects of airborne toxins on human lung cells grown in the lab
+Researchers are using 'mini-lungs' made from cells grown in the lab to test the effects of airborne toxins after workplace contamination and chemical spills.
+The work has won Dr Amanda Hayes, Shahnaz Bakand and Chris Winder of the University of New South Wales (UNSW) a Eureka Prize for research that replaces the use of animals or animal products.
+Hayes says the use of human epithelial lung cells reduces the need for what are often inhumane tests on animals.
+Traditionally, the toxicity of gases and vapours are tested on lab animals that are put into a chamber and subjected to lethal doses.
+But Hayes says the need for such tests can be reduced by using human epithelial cells grown on a porous membrane.
+She says the method is well suited to field work because all investigators need to do is place the cell-containing membrane in a small diffusion chamber and pump in air.
+The 'mini-lungs' can be subjected to a range of tests including energy metabolism and viability, to see how they are responding to the toxin.
+Any cell death resulting from the exposure would immediately set alarm bells ringing.
+Hayes says her group, the only in Australia to use lung cells in this way, has been able to test the effects of chemicals like ammonia and formaldehyde and volatile organic compounds found in paints, solvents and pesticides.
+"The research may open new possibilities for toxicity testing of industrial chemicals, environmental contaminants, respiratory drugs, workplace airborne contaminants and fire combustion products," she says.
+Hayes says the cells tend to be more sensitive to toxins than a functioning lung but the in vitro effects of the toxins on the cells tally well with effects observed in animals.
+The same method can be used to test airborne toxicology on skin and liver cells, she says.
+Other recipients of Eureka Prizes include:
+*&#9;Professor Rick Shine, University of Sydney, for research into Australian reptiles including snakes cross-dressing and lizard nuclear families.
+*&#9;Dr Graeme Batley, Dr Stuart Simpson and Dr Jenny Stauber, CSIRO Energy Technology, for developing standards to measure contamination in sediments and waterways including Sydney Harbour.
+*&#9;Dr Ping Koy Lam, Dr Thomas Symul and Andrew Lance, Australian National University, and Christian Weedbrook, University of Queensland, for the use of quantum encryption to protect online privacy.
+*&#9;Dr Mike Manefield, UNSW, for innovation and leadership in environmental science, specifically for research into how bacteria can help clean up contaminated soil at industrial sites.
+*&#9;Dr Michael Dawson, Professor Matthew England, Alex Sen Gupta, UNSW, for environmental research into modelling ocean circulation.
+*&#9;Dr Michael Valenzuela, UNSW, for bioinformatics research into how mental activity keeps dementia at bay.
+
+Adelaide-born Terence Tao was a full professor at the age of 24
+Australian prodigy Professor Terence Tao has won the mathematics world's version of a Nobel Prize, the Fields Medal, for contributions to harmonic analysis and numerical theory.
+Tao, aged just 31, wins the medal with Russian recluse Dr Grigory Perelman, Frenchman Professor Wendelin Werner and Russian Professor Andrei Okunkov. 
+The medal is another claim to fame for the Adelaide-born academic who earned his PhD from Princeton University at 21 and was full professor of mathematics at the University of California, Los Angeles (UCLA) at 24.
+Asked why he devotes himself to pushing the boundaries of the discipline, Tao says: "Because it's fun." 
+"What interests me is the connection between maths and the real world," he said, following an awards ceremony at the International Congress of Mathematicians in Madrid. 
+Eemeritus Professor Alf van der Poorten, of the Centre for Number Theory Research at Macquarie University in Sydney, salutes Tao's achievement.
+"It's a wonderful thing for Australian mathematics. He was a young genius and [Australia] had people in place to look after him. He comes back quite regularly," says van der Poorten. 
+Professor John Garnett, former UCLA college chair of mathematics, recently placed Tao on a level with Mozart, "except without Mozart's personality problems".
+"Mathematics just flows out of him," Garnett says. 
+Tao was awarded the Fields Medal for his work on a branch of maths that uses equations from physics in the theoretical field of harmonic analysis, a discipline that focuses on acoustic wave frequencies. 
+He also specialises in disciplines including algebraic geometry and number theory.
+Another branch of Tao's research has been prime numbers, based on theories first put forward more than two thousand years ago by the Greek mathematician Euclid.
+Russian recluse
+Meanwhile Perelman, the Russian mathematician who won the medal with Tao, declined to attend the ceremony, choosing instead to stay at home and watch television.
+He declined to comment on the award and on the reasons why he is shunning publicity.
+Perelman resigned from the Steklov Mathematics Institute suddenly in January without explanation.
+Former colleagues say they have not seen him since.
+In 1996, Perelman won an award at the Second European Congress of Mathematics in Budapest. Russian newspapers say that he turned down the prize because he considered the jury insufficiently qualified. 
+But Perelman's international fame in the mathematics world came in 2002 and 2003 when he published two papers online that appeared to solve the Poincar&eacute; Conjecture. 
+The riddle had perplexed mathematicians since it was posited by Frenchman Henri Poincare in 1904. In just 61 pages of sketchily written notes, Perelman seemed to prove it but he never published a full proof in academic journals. 
+The conjecture was one of the so-called Millenium Prize Problems for which the Clay Mathematics Institute in Boston announced a one-million-dollar prize. Perelman never picked up the prize money.
+
+There may be remnants of Neanderthal genes in the nuclear DNA of people with European ancestors
+People of European descent may be 5% Neanderthal, according to a DNA study that questions whether modern humans left Africa and replaced all other existing hominids.
+The same study, published in the latest issue of the journal PloS Genetics, also says West Africans could be related to an archaic human population.
+As both groups spread, the findings suggest we all have a bit of archaic DNA in our genes.
+"Instead of a population that left Africa 100,000 years ago and replaced all other archaic human groups, we propose that this population interacted with another population that had been in Europe for much longer, maybe 400,000 years," says Vincent Plagnol.
+Plagnol, a researcher in the Department of Molecular and Computational Biology at the University of Southern California, and colleague Assistant Professor Jeffrey Wall analysed patterns of ancestral linkage in 135 modern individuals.
+They looked at people from Utah with ancestors from Northern and Western Europe and Yoruba people from West Africa.
+Using statistics and computer modelling, the researchers focused on linkage 'disequilibriums', or sections within genes that did not make sense if only modern human matings are considered.
+The missing genetic links only fit if some other hominid population is introduced into the model, the scientists say.
+"We considered the data from modern human DNA and fitted a model to explain what we see," explains Plagnol.
+"We found that a simple model cannot explain the data if we do not add an 'ancestral population'. If this population did not cross with modern humans, or almost did not, the effect is too small to explain the data. We find that a rate of 5% is what is needed to explain what we see."
+The researchers agree with recent studies that conclude Neanderthals did not contribute any mitochondrial DNA, or mtDNA, genetic material that is passed from mothers to children. 
+But they say other portions of the European genome, such as those associated with nuclear DNA, may still harbour the Neanderthal imprint.
+Plagnol says different parts of the genome have different ancestry, so an individual could have a fraction of a certain chromosome that is inherited from a Neanderthal, but then possess "very typical Homo sapiens mtDNA".
+The scientists are not certain which early human group could have contributed to West African DNA, but both Europeans and Africans in the study showed about the same 5% archaic contribution.
+Neanderthals are believed to have originated in Africa around 400,000 years ago, but they left and then settled in Europe, hence the apparent lack of interaction with modern humans in Africa.
+Alan Templeton, professor of Evolutionary and Population Programs at the University of Michigan, has also conducted DNA studies and comes to similar conclusions.
+"The humans who were in Africa and the humans who were in Eurasia were regularly interchanging genes," he says.
+"There was interbreeding and when humans came out of Africa 100,000 years ago they did not replace these other human populations in Eurasia."
+New technologies are being developed to sequence nuclear DNA from fossils, so in the near future, scientists may learn more about how modern human genes compare with those of archaic humans, like Neanderthals.
+
+The scientists removed a single cell from the embryo using a technique more commonly used in IVF labs
+A US biotechnology company says it has developed a way to make human embryonic stem cells without destroying the original embryo.
+The development, published online today in the journal Nature, could dispel ethical objections to medical research using such cells.
+"It is possible to generate stem cells without destroying the embryo and without destroying its potential for life," says Dr Robert Lanza, chief scientist at Advanced Cell Technology in Massachusetts. 
+Stem cells are the body's master cells, available from many sources. But many experts believe the most powerful and versatile cells may be those taken from days-old embryos.
+Scientists hope to study these cells, discover which compounds enable them to produce any kind of body tissue, and replicate that to make tailored treatments for diseases such as cancer, diabetes and Parkinson's. 
+Lanza's team used a method already used in fertility treatments to remove one cell from a human embryo without harming it. The scientists then grew stem cells from that single cell.
+Although the source embryos were not then implanted in a woman, the scientists say they could have been, with the potential to develop normally. 
+The team used spare embryos from fertility clinics and let them grow to the 8- to 10-cell stage.
+The embryo at that stage is no longer able to divide into twins but the cells can still form any cell or tissue in the body.
+Lanza's team managed to get 19 different cells to grow and got two stem-cell batches, or lines. 
+"These cell lines were genetically normal and retained their potential to form all of the cells in the human body, including nerve, liver, blood, vascular and retinal cells that could potentially be used to treat a range of human diseases," the researchers write. 
+Dr Ronald Green, a Dartmouth College ethics professor who reviewed the experiment for the company, says he is unsure that opponents would accept this research immediately. But he believes they would eventually. 
+"I think many of the opponents are going to bridle at this," he says. "People are unprepared for scientific breakthroughs to resolve these ethical issues." 
+Dr Kathy Hudson, director of the Genetics and Public Policy Center at Johns Hopkins University, says questions remain over the effect of the procedure on an original embryo and the long-term health of any resulting children. 
+Lanza agrees that the method should not be immediately used on people but this is worth studying.
+He says his company would make any stem cell lines available to scientists for free.
+
+Gigantic stromatolites in the 2.74 billion-year-old Tumbiana Formation in the Pilbara region of Western Australia. These indicate that oxygen-producing cyanobacteria were already flourishing in the Archaean era
+There might have been more oxygen in the atmosphere billions of years ago than anyone thought, says an international team of scientists drilling in outback Australia.
+The scientists say that their study of ancient rocks in the Pilbara region of Western Australia may force people to rethink accepted theories of how the prehistoric Earth's atmosphere developed.
+They publish their results today in the journal Nature.
+Up to now it has been generally accepted that the Earth's atmosphere was devoid of oxygen for some 80% of its existence. 
+"The popular model is that there was little oxygen in the Earth's atmosphere before about 2.4 billion years ago," says lead author Professor Hiroshi Ohmoto of Pennsylvania State University.
+But Ohmoto's team has cast doubt on the theory after finding sulfur isotopes, indicating prevalent oxygen, that predate the accepted start of atmospheric oxygenation. 
+The key lies in the fact that while all isotopes of sulfur behave the same chemically, they have slightly differing masses according to the amount of atmospheric oxygen at the time. 
+Isotopes from two sulfur samples the team analysed, one 2.76 billion years old from a lake bed and the other 2.92 billion years old from the sea bed, did not indicate an oxygen-starved atmosphere.
+"We analysed the sulfur composition and could not find the abnormal sulfur isotope ratio [indicating no oxygen]," Ohmoto says.
+"This is the first time that sediment that old was found to contain no abnormal sulfur isotope ratio."
+The team concludes that there are several possible explanations.
+Oxygen levels could have fluctuated wildly over the millennia, going from oxygenless before 3 billion years ago to oxygenated between 3 and 2.75 billion years ago, then back to oxygenless from 2.75 to 2.4 billion years ago.
+Alternatively, the atmosphere could have contained oxygen as early as 3.8 billion years ago and that sulfur usually associated with no oxygen might have been produced at a time of violent volcanic activity.
+Either way, the scientists say, the accepted theories about how the atmosphere evolved needs to be re-evaluated.
+
+It's just not the same any more ...
+Dogs feel especially intense jealousy pangs in a 'love triangle' involving their owner and another more recently introduced person or animal, a new study suggests.
+The finding suggests dogs may also experience pride, embarrassment, shame and other secondary emotions outside the basic emotions such as anger, anxiety and surprise.
+Scientists previously thought only humans and chimpanzees showed behaviours linked to secondary emotions.
+A genetic propensity for jealousy may even run as deep as a dog's ancient wolf ancestors, the researchers say.
+"I would definitely think you would find jealousy in wolves," says lead researcher Dr Paul Morris.
+"For example, sexual jealousy would be an extremely powerful motivator in the wild state. Jealousy would also relate to position in hierarchy and alliances between animals within a pack."
+Morris, a University of Portsmouth psychologist and a member of the university's Centre for the Study of Emotion, and colleague Christine Doe studied 1000 domestic animal owners in the south of England.
+The researchers asked the pet owners to report observations of both primary and secondary emotions in their animals, which included cats, pigs, horses, rabbits, rats and hamsters, as well as dogs.
+All the animals received high scores for secondary emotions, with over 80% of owners saying their dogs showed signs of jealousy.
+When Morris and Doe interviewed participants about their observations, owners repeatedly said their pooches seemed jealous when they introduced a new person or animal to the family.
+Lost love
+Morris also studied the phenomenon directly with his own two dogs, Silver and Jessie. He went out of his way to shower Silver with attention, and then only occasionally gave Jessie her usual pat on the head.
+Jessie showed her teeth and snarled, but contained her anger and tried to push her way back into the mini pack.
+"Jealousy is at its heart related to the real or anticipated loss of love, affection and attention," says Morris.
+"Dog jealousy is different to human jealousy, in that it is tied to the here and now; dog jealousy occurs only in the presence of the interloper. So when I talk about dog jealousy, I see it as a much more primitive and hugely less elaborate version of human jealousy."
+A range of emotions
+Marc Bekoff, a professor of ecology and evolutionary biology at the University of Colorado, is the author of numerous studies and books on animal emotions, most recently two books co-authored with primate researcher Dr Jane Goodall. He agrees with the new findings.
+"I believe that Dr Morris is right. Dogs and other animals do exhibit secondary emotions such as jealousy," he says.
+"I've studied the emotional lives of animals for more than 25 years and was pleased to see his results."
+Morris, who will present his work on canine jealousy at next month's British Association for the Advancement of Science (BA) Festival of Science in Norwich, next plans to study evidence of guilt in dogs and pride in horses.
+
+Male satin bowerbird inspecting the decorations at his bower
+Male satin bowerbirds roam the streets and countryside thieving treasures to adorn their bedrooms, Australian researchers find.
+But there is no honour among thieves.
+While they're out poaching, their own homes are plundered and their finest treasures, blue plastic-lined bottle tops and tail feathers, stolen.
+So why do bowerbirds prefer one treasure over another?
+This is the question researchers including Janine Wojcieszek, an honours student at the University of Queensland at the time of the research, wanted to find out.
+Now she and her colleagues report their findings in the journal Emu: Austral Ornithology.
+Male bowerbirds build stick structures that serve as the base for courtship and mating.
+They decorate their bowers with colourful objects and are known to steal decorations from each other.
+The male satin bowerbird (Ptilonorhynchus violaceus) is particularly drawn to blue objects and researchers hypothesise this could be for reasons of vanity or practicality.
+"It's interesting that different [bowerbird] species have preferences for different colours. The species we looked at particularly like blue things, while the spotted bowerbird that is found in western Queensland prefers white, silver and pinks," says Wojcieszek.
+"One theory is that the bowerbirds choose the colour that best accentuates their own colour. Because satin bowerbirds are blue, they seek blue to show themselves off." 
+Another theory, and one that researchers believe is more likely, is that satin bowerbirds choose blue because that's its 'allotted' colour in the bowerbird world.
+The researchers studied a male bowerbird population around the Bunya Mountains, northwest of Brisbane.
+Wojcieszek labelled the contents of nearly 40 bowers and then returned each day for three months, a mating season, to see what had been added, and stolen, from the bower.
+What she found was a merry-go-round of gathering and stealing.  
+"Every day there were changes to the bowers. Either they had stolen something, or something had been stolen from them."
+The most popular objects, and those most likely to be stolen, were items that reflected ultraviolet light.
+Top of the list were tail feathers from the crimson rosella bird and plastic bottle tops lined with dark blue plastic.
+While the tail feathers were stolen more than any other class of decoration, the blue bottle tops were the most popular decoration relative to their availability on bowers.
+
+Archaeological evidence from ancient dung suggests that the people who lived here kept sheep or goats
+The discovery of a neolithic complex of caves in Greece suggests not all cavemen were club-wielding, nomadic hunter-gatherers, but included some farmers and shepherds.
+They even had the Stone Age equivalent of a toolshed.
+Evidence of such homebody cave dwellers comes from a recent excavation of a cave complex dating from 5300-3900 BC.
+The abode features plastered floors and evidence of crop-growing and an attached stable nearby. 
+"This household was self-contained," says Dr Panagiotis Karkanas, who conducted the excavation of the Kouveleiki caves, located on the cliffs of a shallow valley in the southern Peloponnese.
+"I believe that the site was an ordinary household. The people were living there, cooking, sleeping, etc, probably during the whole year. They were both farmers and shepherds," says Karkanas, an archaeologist at the Ephoreia of Palaeoanthropology-Speleology in Athens.
+Karkanas came to this conclusion after studying objects uncovered within the caves and after performing a detailed microanalysis of the cave sediments.
+Findings will be published in the November issue of the Journal of Archaeological Science.
+The complex consists of two caves, the first of which is divided into two chambers by several rock blocks that appear to have fallen from the roof before the caves were inhabited.
+The cavemen used this natural divide to their advantage, since one of the fallen rocks was curved and straightened to resemble a wall, which created a corridor between the two chambers.
+Burnt manure found in the front chamber suggests a few animals, probably sheep and goats, were housed there. Karkanas says the animals were probably "milkers or very young".
+Cereal husks and residue found within the dung indicates the cave dwellers probably farmed the land in front of the caves.
+He points out that farming in Greece started at about 6500 BC, at the beginning of the Neolithic era, or the New Stone Age.
+In the first cave he found fine painted pottery, polished axes, spindle whirls, clay and marble figurines, grinders and a collection of obsidian, chert and quartz tools.
+The dark, back 'room', measuring about 150 square metres, appears to have been the main area of habitation. Evidence for hearth fires was found. And the floor was plastered with a mixture of burnt dung and red clay.
+Karkanas suggests this type of plaster was unusual for the time, though it became popular later, and is still used today.
+"Plaster made of dung, sometimes burnt, and clay is common today in some villages in Africa and India," he says.
+He says the second cave "was probably used as a complementary activity area", sort of the prehistoric version of a tool shed.
+Nine human burials discovered within the caves suggests some people may have lived their entire lives at the site.
+Moving to the caves
+Curtis Runnels, professor of archaeology at Boston University, says he finds Karkanas' paper to be "both informative and convincing".
+"The move to caves came for many reason, among which was the reorganisation of the economy during this period to emphasise sheep and goat herding," he says.
+"Part of the change was a focus on the production of wool and hair for textiles, which were traded for imported materials, possibly exotic flint or obsidian."
+Runnels thinks people who wanted to practice both farming and herding moved to caves in the somewhat remote, agriculturally marginal regions.
+Then, as the new find suggests, they settled down.
+
+No longer the ninth planet: an artist's impression of Pluto and its moon Charon
+This week's surprise decision to strip Pluto of its planet status has triggered a universe of reactions from astronomers, some philosophical, others downright shocked.
+After heated debate among members of a 2500-strong meeting of the International Astronomical Union (IAU) in Prague, Pluto has been redefined as a 'dwarf planet'.
+It is now considered a distinct object from the other eight traditional planets of the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
+Australian astronomer Dr Simon Johnston, from the Parkes Observatory in New South Wales is shocked at the decision.
+"Up to a week ago I thought we had 12 planets," he says, referring to a definition released by the IAU last week that would have expanded rather than reduced the number of planets.
+The overseer of science investigations on NASA's New Horizons mission to Pluto calls the reclassification rash and illogical. 
+"I think people are going to consider Pluto a planet regardless," says Dr Alan Stern of the Southwest Research Institute in Boulder, Colorado.
+"What they did was scientifically ludicrous and publicly embarrassing," he says. "Pluto is a planet with clouds, weather and geology." 
+Philosophical
+But other astronomers are more philosophical, including Dr Mike Brown of the California Institute of Technology.
+"Pluto is dead," says Brown, who in 2003 discovered an object larger than Pluto that many claimed was the 10th planet
+Brown now accepts the icy rock, called 2003 UB313 and nicknamed Xena, will also be categorised as a mere dwarf planet under the new definition.
+"Pluto would never be considered a planet if it were discovered today, and I think the fact that we've now found one Kuiper-belt object bigger than Pluto underscores its shaky status," says Brown.
+"I'm of course disappointed that Xena will not be the 10th planet, but I definitely support the IAU in this difficult and courageous decision," he says. "It is scientifically the right thing to do, and is a great step forward in astronomy."
+Several Johns Hopkins University astronomers describe the decision as a "muddled" ruling that is unlikely to settle ongoing debates over how to define a planet and whether the term should apply to Pluto. 
+In an informal poll, only one astronomer was pleased to hear about Pluto's new status.
+But at least one astronomer appears indifferent to the decision.
+"The classification doesn't matter," says Dr Louis Friedman, executive director of The Planetary Society. "Pluto, and all solar system objects, are mysterious and exciting new worlds that need to be explored and better understood."
+Pluto fails the test
+Pluto's status has been contested for many years by astronomers who say its tiny size and highly eccentric orbit precludes it from joining the other acknowledged planets. 
+This discovery of Xena prompted questions as to whether Pluto and other largish objects could be considered planets or just simply rocks - rubble left over from the formation of the solar system.
+The IAU defined the core difference between a planet and a dwarf planet as whether the celestial object has "cleared the neighbourhood around its orbit" - in other words, whether the object is massive enough to wield a gravity that draws in rocks and other debris that may clutter its orbital path. 
+This criterion disqualified Pluto whose egg-shaped orbit overlaps Neptune's. 
+The scientists also agreed that, to be called a planet, a celestial body must be massive enough for its own gravity to pull it into a nearly spherical shape, and it must orbit around a star while not itself being a star.
+The large asteroid Ceres, along with Pluto and Xena, will also be defined as a dwarf planet. This is, according to the IAU, an important new class of trans-Neptunian objects. 
+Around a dozen other objects are already dwarf candidates and all other objects, except satellites, will be known as "small solar system bodies" under the new definition.
+Hate mail from angry children
+Pluto was discovered in 1930 by a 24-year-old American astronomer, Clyde Tombaugh who died in January 1997, convinced he had achieved eternal recognition as the discoverer of the solar system's ninth planet. 
+Tombaugh's announcement smashed the perceived boundaries of the solar system, established 84 years earlier with the discovery of Neptune.
+This week's Prague vote will have similarly widespread public implications with models and textbooks of the solar system becoming instantly obsolete.
+Officials at the American Museum of Natural History in New York, who have been at the vanguard of the movement to demote Pluto, say they have already received irate calls from the public.
+"We had enormous numbers of telephone calls and I would say things that verged on hate mail from second-graders - very angry children who said, 'What have you done? This is the cutest, most Disney-esque of the planets. How could you possibly demote it?'" says Dr Michael Shara, the museum's astrophysics curator. 
+"It's going to be a difficult thing to accept at first, but we will accept it eventually, and that's the right scientific and cultural thing to do," says Brown.
+But at least one young visitor to the Smithsonian Institution's National Air and Space Museum, 15-year-old Quinn Huebner, is happy.
+"It's one less planet to memorise," he says.
+
+Torres Strait Islanders with diabetes may be placing their kidneys under further strain by eating dugongs contaminated with cadmium
+High cadmium levels in dugongs and turtles in Australia's north may be affecting the kidneys of Torres Strait Islanders who eat these animals as delicacies, preliminary research suggests.
+Research led by epidemiologist Dr Melissa Haswell-Elkins of the University of Queensland's North Queensland Health Equalities Promotion Unit suggests the cadmium may be worsening Torres Strait Islanders' diabetes-related kidney damage.
+But until the team has more data, Haswell-Elkins is recommending Torres Strait Islanders keep eating these traditional foods. 
+She says earlier studies have found that the cadmium comes from natural sources in the ocean, rather than industrial pollution, and concentrates in the liver and kidneys of dugongs and turtles.
+Studies show cadmium levels in these long-lived animals are "well above" acceptable levels, Haswell-Elkins says.
+This may be an issue, she says, as there is some suggestion that the kidneys of people with diabetes are more sensitive to being damaged by cadmium.
+So her team investigated the possible impact of the cadmium from traditional seafoods on 122 Torres Strait Islanders, Indigenous Australians who are already at risk from kidney damage due to diabetes.
+The researchers found that people who eat more dugong and turtle have more cadmium in their urine and also worse albuminuria, a marker of kidney damage in which high levels of the protein albumin are excreted in the urine.
+The researchers think that cadmium in traditional foods could be contributing to diabetes-related kidney damage.
+And they think health researchers should pay more attention to cadmium as one of the many factors that can affect kidney health.
+But Haswell-Elkins says it's too early to say whether the cadmium is causing the kidney damage or whether already-damaged kidneys are simply allowing more cadmium to escape in the urine.
+She says people should not be afraid of eating their traditional foods.
+Until we understand how significant this source of cadmium is, she says, it is best to be more concerned about the well-established risk factors for diabetes such as hypertension, lack of exercise, poor diet, alcohol, obesity and smoking.
+Some of the team's research has been published online in the Journal of Exposure Science and Environmental Epidemiology.
+
+The fingertip device can sense acceleration and inertia to more accurately mimic a real finger
+A fingertip device that recognises hand gestures and senses texture is being developed in the US.
+The digitiser could one day input information without a keyboard; come in handy for gaming, where it could imitate squeezing a trigger; and be worn to paint on a screen by moving a finger through the air.
+The 'Fingertip Digitizer', was developed by mechanical engineer Youngseok Kim and Associate Professor Thenkurussi Kesavadas, director of the University at Buffalo's Virtual Reality Laboratory.
+They say it could be used for everything from inputting information into a computer or PDA to transferring the physical characteristics of an object to a computer for design purposes.
+"With this device a computer, cell phone or computer game could read human intention more naturally," says Kesavadas.
+"Eventually the Fingertip Digitizer may be used as a high-end substitute for a mouse, a keyboard or a joystick."
+According to Kim and Kesavadas, other gesture-recognition devices available on the market can sense movement but not force.
+And although there are several force-feedback, or haptic devices, none can measure details of dynamic fingertip activities, including acceleration and inertia.
+"Our digitiser bridges the contact and non-contact input strategy," says Kim. "We keep track of everything happening on your fingertip."
+After all, says Kesavadas, the fingertip is the most intuitive interface humans already posses. We use it to point, push buttons, touch objects and sense textures.
+The duo's device is equipped with three sensors to give it a broad range of function.
+A position sensor keeps tracks of where the digitiser is in 3D space and captures its direction. An accelerometer gauges speed, and a force sensor at the tip measures pressure.
+
+Who needs ghostbusters when you've got Newton, says a scientist who has used physics and maths to poke holes in the way Hollywood depicts ghosts and vampires. 
+In a paper, published recently on the physics website arXiv, theoretical physicist Professor Costas Efthimiou of the University of Central Florida shows that when it comes to things supernatural, the figures just don't add up.
+For instance, the ability to walk through walls is a common talent of celluloid ghosts.
+But Newton's laws of physics suggest that if a ghost can walk it shouldn't be able to pass through walls, say Efthimiou and Cornell University postgraduate student Sohan Gandhi.
+Newton says a body at rest will remain at rest until it's acted on by an external force and for every action there is an equal but opposite reaction.
+So in order to walk, we apply a backward force on the floor with our feet, propelling the feet up and us forwards.
+But if a ghost can walk through walls, it must be "material-less", the authors argue, and incapable of exerting force.
+By the same token, a ghost that can walk through walls should also sink through the floor, and a ghost that can walk should be bouncing off the walls it tries to pass through.
+"The depiction of ghosts walking contradicts the precept that ghosts are material-less," they write.
+Ghostly chills
+Sharp drops in temperature are also associated with the arrival of a ghost.
+But the paper says physics, which suggests that a sense of cold is correlated more to the rate at which heat is transferred from bodies to the environment than actual temperature, can provide an explanation. 
+"It has become almost a Hollywood cliché that the entrance of a ghostly presence be foreshadowed by a sudden and overwhelming chill," they write.
+"This feature of supposed ghost sightings lends itself naturally to physical explanation."
+Efthimiou and Gandhi say when a warm object is placed next to a cold object, energy flows from the warm body to the cooler body, cooling the warm body.
+In a room with a high window or a door with a gap, the cool air from outside displaces warm air inside, creating a system of heat cycles and eddies.
+The effect is increased because humans are more sensitive to rapid changes in temperature even if the absolute change is small.
+A 2001 UK investigation of the famous Haunted Gallery at Hampton Court, by the University of Hertfordshire's Dr Richard Wiseman, found that hidden doors were letting in draughts.
+This produced a combination of air currents that caused temperatures to plummet up to 2°C in some parts, the paper says.
+Blood suckers?
+Efthimiou and Gandhi also use the mathematical principle of geometric progression to rule out the existence of vampires.
+They argue it would take just two and a half years for vampires to wipe out the entire human race from the day the first one appeared, based on the myth that vampires turn their victims into other vampires by sucking their blood.
+If vampires feed once a month, the great grandaddy of all vampires would have killed one human and produced one vampire in the first month. So in total there would be two vampires and one less human, or a tally of vampires 2, humans -1.
+By the next month, the 2 vampires would kill 2 humans, and so on. 
+After n months there would be 2 x 2 x 2 ... x 2 = 2^n, or a geometric progression with ratio 2.
+"The vampire population increases geometrically and the human population decreases geometrically," they say.
+Using the principle of reductio ad absurdum, they conclude that vampires can't exist as their existence contradicts the existence of humans.
+Professor Alan Carey, dean of the Mathematical Sciences Institute at the Australian National University, says the paper successfully debunks the depictions of the supernatural in the movies.
+"They poke holes in the clichés and mistakes that are made, and that's not too hard to do," he says.
+
+Archaeolgists believe structures like the Tevaitau fort reflect hostility between population groups competing for resources
+The Polynesians had trouble reaching remote South Pacific islands, according to a new study that dents their reputation as great seafarers.
+An archaeological study shows they settled Rapa, an island southeast of Tahiti, more recently than anyone thought.
+Professor Atholl Anderson, of the Australian National University, and international colleagues publish their research in the current issue of the journal Antiquity.
+Dating of charcoal from archaeological sites on the 20 square kilometre island suggests the first settlers arrived at Rapa as late as around 1200 AD, Anderson says.
+The findings come after dates for the settlement of nearby Easter Island were recently revised to around the same time.
+"What these pieces of archaeological research show is that the more isolated islands were reached very late in the history of the settlement of the Pacific, indicating that probably the seafaring technology was not as good as we once thought," Anderson says.
+"The Polynesians were once regarded as almost superhuman seafarers who could go anywhere that they wanted. But now it doesn't look like that at all.
+"It looks like they actually had great difficulty finding these remote and isolated places."
+Anderson says the Polynesians are believed to have radiated out from islands like Fiji, Tonga and Samoa to more remote islands like Rapa after a 1500 year migratory lull, driven further afield by population pressure and food shortages.
+Mysterious forts
+After Rapa was settled, the population rapidly increased and spread across the island, Anderson says.
+Archaeological analysis of swamps shows signs of rapid deforestation and erosion along the coast, suggesting the population was running out of land to plant taro crops.
+The population apparently splintered into competing groups that set up formidable stone forts, consisting of a central tower surrounded by domestic terraces. 
+"It's always been a bit of a mystery as to why this very isolated island should have such a huge number of massive forts on it," Anderson says.
+"The forts represent the time ... that it becomes a highly competitive society and ... they were simply fighting all the time."
+Radiocarbon dating suggests they relocated from their coastal rock shelters to inland fortresses about 300 years after arriving and about 150 years before the first contact with Europeans in 1790.
+The conclusions are based on 48 radiocarbon dates from a variety of sites, including five of the 16 known coastal shelters and four of the 15 fortifications.
+A microcosm of the world
+The University of Oregon's Assistant Professor Douglas Kennett, who co-authored the paper, says Rapa tells a compelling story of population expansion, environmental degradation and increasing warfare.
+"Rapa is a little microcosm of our planet. There are lessons about the consequences of population growth to be learned there," he says.
+Anderson says time has recorded a classic pattern at Rapa.
+"The argument is if any population is confined it overuses its resources [and] the result of that is almost always competition between units, groups, families, and ultimately war."
+
+In some parts of the world, it really is a man's world. Researchers say sex selection in societies that favour boys mean there are at least 80 million missing females
+A preference for male babies and a resulting sex-ratio imbalance could lead to a destabilised society, researchers warn.
+Their study in the Proceedings of the National Academy of Sciences says the imbalance would leave more men unmarried, raising the risks of antisocial and violent behaviour.
+The researchers say that parts of China and India would have 12-15% more men over the next 20 years, many of them in rural areas and with a limited education.
+"The growing number of young men with a lack of family prospects will have little outlet for sexual energy," write Dr Zhu Wei Xing of China's Zhejian Normal University and Dr Therese Hesketh of the Institute of Child Health at University College London. 
+"This trend would lead to increased levels of antisocial behaviour and violence, as gender is a well-established correlate of crime, and especially violent crime," they say, adding the trend would threaten stability and security in many societies.
+Sex ratios are already distorted in large parts of Asia and North Africa, and sex-selective abortion and discrimination in healthcare for girls have led to higher female mortality. 
+"There are now an estimated 80 million missing females in India and China alone," the researchers write. 
+China introduced a one-child policy in 1979 to control population growth, but it has led to a rise in the male-to-female ratio from 1.11:1 in 1980-89 to 1.23:1 in 1996-2001, according to a study published this month in the British Medical Journal.
+In 2004, 48.6% and 48.7% of the population in China and India, respectively, were female.
+In contrast, females comprise 49.1% of the total population in East Asia, and 52.1% in all of Europe and Central Asia, according to figures from the World Bank. 
+The authors called for measures to reduce sex selection and an urgent change in cultural attitudes, or dire consequences could follow. 
+"When single young men congregate, the potential for more organised aggression is likely to increase substantially and this has worrying implications for organised crime and terrorism," they say.
+
+This mite came to a sticky end millions of years ago in the Peruvian Amazon
+Insects that became trapped in tree resin between 12 and 15 million years ago show that Amazonia hosted an astonishingly rich variety of life, French researchers say. 
+The resin, which hardened into glass-like amber, has yielded at least 13 previously unidentified species of insects, three species of mites as well as more than 30 new species of algae, lichen and other microorganisms.
+A team led by Dr Pierre-Olivier Antoine at the University of Toulouse publishes the research online today in the Proceedings of the National Academy of Sciences.
+It is the third amber fossil find in South America, but the first in Amazonia. 
+Of the 13 insect species, 12 belong to different families, which demonstrates that Amazonia was already hot, humid and a remarkable generator of biodiversity in the middle Miocene, an era that spanned 23 to about 5.3 million years ago, Antoine says.
+Fossilised insects and microorganisms are extremely rare, as they do not have a tough internal skeleton like, for instance, dinosaurs, early birds or hominids.
+As a result, these tiny fossils only turn up in exceptional finds, embedded in amber or in fine-grain chalky deposits. 
+Three expeditions have been carried out to explore the amber deposit, which was found accidentally on the banks of the Amazon near the Peruvian city of Iquitos and is covered by river water for much of the year. 
+About 100 fragments of amber, totalling around 500 grams have been recovered from the site and are still being analysed.
+"To find so many species in such a small quantity of amber proves that at that time Amazonia had phenomenal biodiversity, close to today's," says Antoine. 
+Some scientists have argued that Amazonia's broad variety of life was acquired relatively recently. 
+The team, from France's National Centre for Scientific Research (CNRS), says that some of the specimens are so extraordinarily preserved that some cells appear to be undamaged. 
+If so, there are hopes that enough DNA may be recovered from them to build a family tree of their genetic lineage, the CNRS says.
+
+The emerging space tourism market has sparked the need to reassess what we really mean by space, a legal expert says
+We need a legal definition of where space begins and ends to ensure future space tourists get what they pay for, says an Australian expert in space law.
+Associate Professor Steven Freeland from the University of Western Sydney will speak about emerging issues in space law at a seminar next week.
+Freeland says there are plenty of laws and treaties dealing with what we can and can't do in space. 
+For example, it's illegal to claim territory in space or to use space for military or non-peaceful purposes.
+But he says there's no actual legal demarcation of where space begins and the sky ends.
+"The argument has always been why do we really care? Why do we really need to know?"
+But he says new technology, including the prospect of a growing space tourism market, has given these questions a pressing new relevance.
+"If we look at space tourism ... [people] are going to want a certificate that says 'I've been in space', not 'hey you've been very high up in the air'," he says.
+"And from a commercial perspective the industry would love to be able to say 'you've been in space', because you're not going to pay US$100,000 to be very high up in the air."
+What's a life worth in space?
+Freeland says other space tourism issues potentially affected by whether a craft is in space or the air include insurance, liability, traffic control and rescue obligations.
+Even the right to claim the term 'astronaut' may have to be revisited.
+"[Some operators] say we'll all become astronauts and we'll get our astronaut wings.  But 'astronaut' is a term under space law," he says.
+"Are you and I an astronaut just because we paid money to sit in this thing?"
+Freeland says the existing space laws are badly in need of an overhaul because developments like space tourism were never envisioned at the time they were drafted.
+"You have to have legal certainty [about] what law applies, whether it's international air law or international law of outer space or a combination of both," he says.
+Who decides?
+Currently decisions about matters like demarcation are made by the United Nations General Assembly on the basis of recommendations from its Committee on the Peaceful Uses of Outer Space (COPUOS).
+COPUOS takes advice from bodies like the International Institute of Space Law, of which Freeland is a member.
+He says while Australia set something of a benchmark in defining space as beginning at 100 kilometres above sea level under its 1998 space activities legislation, international bodies have been slow to act.
+Freeland says demarcation was at the top of the list when COPUOS first met in 1962 but "here we are and we still don't have a legal demarcation".
+He says major players in the space race, like the US, have resisted moves to pin down a definition of space, largely because it could restrict their ability to carry out certain activities that would be banned or limited under space law.
+
+New Orleans houses swamped by floodwaters after Hurricane Katrina
+In the year since the levees broke in New Orleans, scientists and engineers have found a lot of reasons for hope and despair about the future of Louisiana's coast.
+The good news is that the solution may be in the Mississippi River itself.
+The bad news is that some coastal areas, including New Orleans, could be sinking a lot faster than expected. Maybe too fast. Or maybe not.
+First there's that murky Mississippi water. Mark Twain, who had a stint as a Mississippi riverboat pilot, reported that a glass of the fresh muddy river water was once considered "wholesomer to drink" than clear water of the Ohio River on account of the "yaller" mud.
+In fact, each year the great river carries about 100 million tonnes per year of silt, sand and gravel through engineered channels, past New Orleans and into the depths of the Gulf of Mexico.
+That's equivalent to 10 Superdomes packed tight with dirt, each year, says Denise Reed, professor of geology and geophysics at the University of New Orleans, who has been working on finding solutions for the coast.
+Year in and year out, 100 million tonnes adds up to a whole lot of real estate flowing freely right into, then right out of, a place that is losing land at more than 120 square kilometres each year.
+"Here we are, going cap-in-hand to Congress for money when our most valuable resource is being wasted," Reed says.
+If, instead of being artificially channelled to the southernmost tip of the Mississippi Delta and dumped into deeper waters, most of that muddy water sediment were allowed to flow into the shallow surf zones further north, it would get caught up in the never-ending shoving match between the river and the sea.
+Once there, as is the case along any shoreline near a river, ocean waves would serve as nature's free earth-moving machines and build up beaches that could protect the land from storm surf.
+It's the very process that built the Louisiana coast in the first place, Reed says.
+"The mother lode is still being wasted," she says. "We have got to keep it in the shallow water."
+Muddy process
+So just what kind of project would keep that liquid real estate in Louisiana, while at the same time protecting homes and cities, maintaining a navigable river and restoring the troubled Mississippi Delta wetlands?
+That question is now the focus of feverish discussion and planning by Louisiana's brand-new Coastal Protection and Restoration Authority, or CPR Authority, says Robert Twilley, a professor of wetlands biogeochemistry at Louisiana State University (LSU).
+Back in November, just two months after Katrina, the Louisiana State Legislature created the CPR Authority by blending together the state Department of Natural Resources and the state Department of Transportation and Development.
+What this means, says Twilley, is that for the first time protection, which usually means buildings, is being integrated with restoration, which usually refers to coastal wetlands.
+For decades the two goals have been largely perceived as opposites.
+"It completely changed overnight our bedfellows," says Twilley. "It really has, in the last year, focused a very clear discussion on levees and wetlands as an integrated protection system."
+The CPR Authority's first daunting task is to work with the various levee boards and the federal government to craft a comprehensive protection and restoration plan for the Louisiana coast.
+The plan is to be gleaned from vast amounts of data and delivered to the public in January, Twilley says.
+Muddy mystery
+One of the most slippery and yet fundamental aspects of all that modelling and planning is figuring out subsidence, or just how fast the Louisiana coast is sinking and whether there is anything we can do about it.
+Just as Katrina struck last year, scientists were in the midst of a stormy debate over subsidence, Twilley recalls. 
+Rates of subsidence now range from just less than a millimetre per year to 170 times that rate.
+Geologists know of at least three things that could be causing the ground to sink lower along Louisiana's coast.
+One is the extraction of oil, gas and water from the ground, which was implicated last year in a US Geological Survey report. 
+Another is the somewhat limited natural settling and compaction of river sediments that make up the ground.
+Lastly, there are deeper 'tectonic' changes involving the rising and falling of shifting large blocks of real estate along faults, the sort of thing that's more common in fault-ridden places like California.
+In April, Twilley's LSU colleague Professor Roy Dokka came out with a paper in Geology, in which he argued that faulting and what looks like a gigantic, slow-moving regional landslide is the cause of almost three-quarters of New Orleans' subsidence.
+Dokka revised regional elevation data using precision Global Positioning System equipment and discovered a higher rate of subsidence over the past 50 years is almost all caused by this tectonic movement.
+Then in July Geology published a paper by Tulane University's Associate Professor Torbj&ouml;rn T&ouml;rnqvist, who used an entirely different approach.
+T&ouml;rnqvist surveyed long-buried wetland peat layers in outlying areas to come up with entirely different and milder subsidence rates.
+"I think there is a very balanced dialogue going on," says Twilley of the two studies. "I have a lot of respect for both of them."
+It's just the way science works, agrees Reed, and it's not surprising, considering that the two studies are so different in methods and the places they examined, she says.
+Discovering the truth about subsidence is going to take a lot more work and a great deal of time, all of which Dokka, T&ouml;rnqvist and others are already investing at top speed.
+Like the people of the CPR Authority, the Army Corps of Engineers, the levees boards and everyone else along the Louisiana coast, the subsidence researchers are urgently looking for answers so planners can make the right decisions and everyone can get to work before another Katrina-sized storm comes anywhere near.
+"The problem is," says Twilley, "it takes a lot of time, and time we don't have."
+
+An instrument on board this NASA satellite measured simultaneous vertical profiles of ozone and other compounds
+Earth's protective ozone layer, which was notably thinning in 1980, may be fully recovered by mid-century, climate scientists say.
+Ozone in the stratosphere, outside the polar regions, stopped thinning in 1997, the scientists found after analysing 25 years worth of observations. 
+The analysis will be published in the Journal of Geophysical Research - Atmospheres. 
+The ozone layer shields the planet from the Sun's harmful ultraviolet radiation. But human-made chemicals, notably the chlorofluorocarbons found in some refrigerants and aerosol propellants, depleted this stratospheric ozone, causing the protective layer to get thinner. 
+The scientists say the ozone layer's comeback is due in large part to compliance with the 1987 international Montreal Protocol, which aimed to limit emissions of ozone-depleting chemicals.
+"These results confirm the Montreal Protocol and its amendments have succeeded in stopping the loss of ozone in the stratosphere," says Dr Eun-Su Yang of the Georgia Institute of Technology, who led a team that analysed the data. 
+"At the current recovery rate ... the global ozone layer could be restored to 1980 levels - the time that scientists first noticed the harmful effects human activities were having on atmospheric ozone - sometime in the middle of this century," Yang says. 
+Researchers from NASA and other agencies reported in June that the so-called ozone hole over Antarctica would recover by around 2068, which is some 20 years later than previously expected. 
+The Antarctic ozone hole is a massive loss of ozone that occurs each spring in the southern hemisphere. 
+A similar, though smaller and less severe, ozone hole has been reported in the Arctic.
+While ozone is a beneficial shield in the stratosphere, some 10 to 50 kilometres above Earth's surface, the ozone encountered at ground level can be damaging to lung tissue and plants and is a major component of smog.
+
+This supernova, indicated by a white arrow, was caught exploding in real time
+Astronomers say they have recorded a supernova in real time: the death explosion of a massive star that is typically only ever spotted days after the blast.
+In studies that appear today in the journal Nature, four international teams of astronomers say the extraordinary blast was preceded by a short, sharp burst of gamma rays.
+It provides the first confirmation of a theory that supernovae follow an "early warning signal" of this kind, they say. 
+Supernovae occur when a huge, mature star runs out of fuel and catastrophically and explosively collapses in on itself.
+The edge of a blast, called the shock breakout, is a wave of energy that ranges across the frequency spectrum.
+In February this year, an orbiting US sentinel, the telescope Swift, picked up a gamma-ray burst (GRB) in a star-forming galaxy about 440 million light-years away, towards the constellation of Aries.
+As it swivelled in the direction of the blast, Swift also relayed its discovery to major ground-based and space-based observatories.
+The combined data from their sensors has been pieced together to give a picture about what happened over the next 17 days. 
+After a supernova
+GRBs have long been associated with the aftermath of supernovae.
+They are typically huge releases in energy. In a few seconds, they can spew out more energy than the Sun will do in its entire expected lifetime of 10 billion years. 
+But this GRB was highly unusual. It lasted almost 40 minutes, whereas a typical GRB only lasts a few milliseconds or tens of seconds at the most. It was also remarkably weak, a mild type of GRB known as an x-ray flash. 
+The astronomers believe that this burst was a high-energy jet that pierced through the doomed star from its collapsing core. In essence, it was sending out a warning that a supernova was imminent. 
+Suddenly, as the GRB faded away, the massive star blew itself into smithereens, sending out a "slightly aspherical" shockwave that rocketed across the heavens. 
+The glowing remains
+The star's glowing remains were confirmed optically two days later and classified as supernova SN 2006aj. 
+"Usually these events are not detected until after the supernova has brightened substantially in the optical wavelength, many days after the initial  explosion," says Professor Keith Mason, chief executive of the UK's Particle Physics and  Astronomy Research Council, which operates an ultra-violet/optical telescope aboard Swift.
+"But on this occasion we were able to study the remarkable event in all its glory, from the very beginning." 
+One analysis, led by Alex Filippenko, a professor of astronomy at the University of California at Berkeley, suggests that the star had a mass of about 20 times that of the Sun before it blew apart. 
+Neutron star or black hole?
+The remains of a supernova can become a neutron star, a fast-rotating star that pulses with high energy.
+Alternatively, in the case of very massive stars, it can form a black hole, an object whose gravitational pull is so great that not even light can escape from it.
+Supernovae have played in important role in superstition and knowledge. 
+A supernova spotted by the Danish astronomer Tycho Brahe in 1572 and which lingered for a further 18 months helped overturn the notion established by Aristotle that the universe was fixed and unchanging. 
+Tycho's star had such an effect on the popular mind that it reputedly was the inspiration for the celestial omen in Shakespeare's Hamlet. 
+Warning
+In a commentary in the journal, Assistant Professor Timothy Young of the University of North Dakota in the US says the research has shown that at least some GRBs are warnings of the imminent explosion of massive stars. 
+"All four papers make clear that the exploding object sent out both a slightly aspherical shockwave, typical of a supernova, and a jet-like stream of material characteristic of a GRB," he says.
+
+Molecules that mimic those in plants may be used to create organic solar cells
+Synthetic molecules that mimic chlorophyll in plants may one day form the basis of highly efficient solar cells, say Australian researchers.
+Professor Max Crossley's molecular electronics group at the University of Sydney recently presented its research at the International Conference on Porphyrins and Phthalocyanines in Rome.
+"Nature has evolved this very efficient process, over millions of years, for harvesting light and then converting it into energy," says Crossley.
+"We're trying to mimic aspects of natural photosynthesis."
+Dense arrays of chlorophyll molecules in leaves are responsible for converting light energy to electrical energy and then to chemical energy.
+Critical to this function of chlorophyll is the pigment porphyrin, which is attached to a central magnesium ion.
+Crossley and team have made a synthetic form of chlorophyll that performs the first part of that process, converting light energy to electrical energy.
+As in nature, when a large number of these synthetic molecules are arranged in a dense array they act in concert to efficiently collect photons of light.
+"There has to be a lot of them because if there was only one it would be a very inefficient process," says Crossley.
+Soccerball-shaped molecules
+The researchers made a synthetic chlorophyll molecule shaped like a soccer ball.
+It has a dendrimer scaffold, a highly branched nanosized polymer made of carbon, hydrogen and nitrogen.
+Attached to the dendrimer are synthetic versions of the light-harvesting pigment porphyrin.
+Spherical carbon molecules called buckyballs sit between the porphyrin and soak up electrons from the photons of collected light.
+Crossley and team have used an array of the synthetic chlorophyll to build a prototype of an organic solar cell.
+Based on what nature delivers, they expect to eventually have much more efficient solar cells than exist at the moment.
+A leaf is about 30-40% efficient at converting light to electricity and this compares with just a 12% efficiency for conventional silicon-based solar cells.
+"We have the basis of a biomimetic organic photovoltaic device or solar cell," says Crossley.
+"In the long term what we're trying to do is have something we can simply paint on a roof, like a thin layer."
+He says the team also hopes to make storage devices to replace metal-based batteries.
+Nano efficiency
+Crossley says conversion of light energy to electrical energy is most efficient when the molecules used to absorb the light are not too large.
+Ideally, their size is around half the wavelength of the light being absorbed, which he says is 300 to 800 nanometres for visible light.
+"You can't have a very thick material because light doesn't pass through it," says Crossley.
+He says there are many groups using nanotechnology to build more efficient solar cells.
+"It's a very hot topic," says Crossley. "So people are endeavouring to use all sorts of novel nanomaterials and ideas in order to achieve high efficiency in the generation of electricity from solar energy."
+Team member and postdoctoral researcher Dr Deanna D'Alessandro is one of 16 scientists who are presenting their research to the public for the first time under the Fresh Science initiative.
+
+Anger and hostility may affect hormones that in turn disrupt the immune system, causing chronic lung inflammation
+Angry and hostile middle-aged men suffer accelerated wear and tear of their lungs, a new US study shows.
+In 1986, Harvard School of Public Health doctors recruited 670 men aged 45-86, with the average age of 62.
+The researchers assessed the doctors' hostility using a yardstick test called the Cook-Medley Scale and their lung power, determined by the volume of air expelled in a second. 
+The volunteers were tested three times over the next 8.2 years on average. 
+After filtering out factors that could distort the result, such as smoking and education, the researchers found that the men's hostility rating was closely linked to lung capacity. 
+They reported the results in the journal Thorax.
+Those who became more hostile suffered a more rapid decline in lung power than counterparts whose temperament remained unchanged or became more positive. 
+Every point increase in hostility was associated with a loss of 9 millilitres in the air expulsion test.
+Previous research has linked hostility and anger with heart disease, asthma, hypertension, irritable bowel syndrome and other disorders, although the exact causes are unclear. 
+One theory is that anger and hostility affect hormone processes that in turn disrupt the immune system, causing chronic inflammation that damages tissue. 
+But Dr Peter Lehrer of the University of Medicine and Dentistry of New Jersey says that an association between hostility and lung function does not necessarily equate to cause.
+"Personality, as well as physiology, can change over time, and deterioration in health and physical function can lead to negative emtions as well as vice versa, including for respiratory disease," he writes in a commentary in the same issue of the journal.
+
+Some women with normal pregnancies have caesareans as a matter of choice
+While it is rare for women in developed countries to die from childbirth, a new French study has found caesarean delivery more than triples the risk.
+The findings are from a study led by Dr Catherine Deneux-Tharaux of the Maternite Hopital Tenon in Paris, published in the September issue of Obstetrics & Gynecology. 
+"This study shows that caesarean delivery is associated with a three-fold increase in the risk of postpartum maternal death as compared with vaginal delivery," the researchers say.
+There has been a continuous rise in the rate of caesareans in developed countries.
+And some professionals have recently proposed elective caesarean delivery should be an acceptable first-choice method of delivery for women with normal pregnancy, say Deneux-Tharaux and colleagues.
+But, they say, the increased risk of maternal death needs to be taken into account by clinicians and women when balancing risks and benefits of vaginal versus caesarean delivery.
+Deneux-Tharaux and team looked at 65 maternal deaths that occurred between 1996 and 2000, and that were reported to a French confidential enquiry on maternal deaths. 
+They compared these to a control group of 10,244 women selected from the French National Perinatal Survey.
+All of the deaths followed births of a single child and were not due to conditions existing prior to delivery. The women had also not been hospitalised during pregnancy. 
+The researchers found that the risk of death - from blood clots, infection or complications from anaesthesia - was 3.6 times higher for women who had caesareans.
+The risk of death after childbirth was increased whether or not the caesarean was performed before the onset of labour or during labour.
+The researchers say previous studies of the relationship between caesarean delivery and risk of maternal death have reported inconsistent results.
+"Our objectives in this study were to provide a valid estimate of the risk," they say.
+Although rates of maternal death in most developed countries are relatively low, in the US women have a 1 in 3500 chance of pregnancy-related death.
+The American College of Obstetricians and Gynecologists say the incidence of maternal mortality has not significantly decreased in the last two decades.
+But Deneux-Tharaux and team say there is persistent underidentification of maternal mortality in developed countries.
+A recent study found a 19% underreporting of maternal deaths in vital statistics from France, they say.
+
+Could tinkering with the DNA of immune cells be a cure for deadly cancers?
+Two out of 17 patients with a deadly form of skin cancer have had their tumours wiped out by genetically altered immune cells, US researchers report.
+But while the findings are being hailed as evidence that the troubled field of gene therapy can successfully treat cancer, other experts say the results are disappointing.
+Dr Steven Rosenberg of the US National Cancer Institute (NCI) and colleagues report their findings today online ahead of print publication in the journal Science.
+The technique "represents the first time that gene manipulations have been shown to cause tumour regression in humans," Rosenberg says.
+The researchers infused 17 patients suffering from metastatic melanoma with their own white blood cells that had been removed and genetically engineered to fight tumours. 
+The patients' T-cells had been modified with genes that code for receptors designed to recognise melanoma cells.
+The cancer was eliminated in two male patients, the researchers say. 
+In one case a 52-year-old man had a tumour in his armpit disappear and another on his liver shrunk enough to be surgically removed. He remained disease-free 19 months after treatment, the study says. 
+Another patient, a 30-year-old man, had a lung tumour recede and showed no signs of disease 18 months later. 
+"The tumours went away and both of the patients are now completely disease-free over a year and a half later," says Rosenberg who is chief of surgery at the NCI.
+Before the experiment, the patients had advanced skin cancer that was not helped by standard therapies and they were expected to live just three to six months, he says. 
+Disappointing response
+But the cancers in the remaining 15 patients did not respond to the treatment and other gene therapy researchers say the results may be a step forward, but are no cause for celebration.
+"This certainly is a significant technical advance that is going to fuel more interest ... and more enthusiasm, I hope, among researchers," says Dr Michel Sadelain, director of Memorial Sloan-Kettering Cancer Center's somatic cell engineering laboratory. 
+But, he adds, it is "undeniable the response here is rather disappointing".
+Professor Savio Woo of Mount Sinai School of Medicine and a past president of the American Society of Gene Therapy says the researchers "need to do it in more patients and get better response rates, and when that happens we can all pop the champagne".
+Scientists have touted gene therapy as holding great promise for a range of ailments, but safety problems have set the field back. 
+One experiment cured two French "bubble boys" with a rare immune disorder, but later gave them leukaemia, and an 18-year-old died in a 1999 gene therapy experiment. 
+Rosenberg says there are no side effects from the melanoma gene therapy. 
+It was administered with the drug interleukin-2, which can cause fluid retention, he says.
+The researchers hope the same approach can fight breast, lung and other cancers and are seeking regulatory approval to test the technology in other patients.
+
+The new spaceships are meant to replace the space shuttle fleet to be retired in 2010
+Europe's first probe to the Moon crashed into the lunar surface at the weekend giving stargazers around the world an astronomical fireworks display.
+Scientists hope that dust kicked up by the impact of the European Space Agency (ESA) probe will tell them more about the Moon's origin.
+The SMART-1 probe smashed into a plain called the Lake of Excellence on the southwestern side of the Moon's face, "producing a more intense flash than expected", says the mission's chief scientist Professor Bernard Foing.
+The craft plunged to the surface at a speed of 2 kilometres per second, throwing up a cloud of dust.
+ESA estimates that the impact would leave a crater measuring 3-10 metres in diameter and 1 metre deep.
+Over the past three years, operating with a full-time staff of just seven and a total budget equivalent to US$151 million dollars, the little probe has been testing new technology that one day could help put humans on Mars. 
+Scientists also say that the 20,000 detailed photos transmitted by the craft will yield a fresh look at the Moon, revealing Earth's satellite as a place of surprising complexity and promise rather than a lifeless rock with little to offer except grey dust. 
+"SMART-1 is the vanguard" of future space missions, says the craft's operations manager, Octavio Camino-Ramos.
+"Almost everything on board was innovative. It was a mission to test technology; the science was an extra plus." 
+Ion thruster
+An ion thruster engine has propelled the cube, which measured just 1 metre across and weighed 350 kilograms, since it was launched in September 2003. 
+The engine type has only been used once before, with the US craft Deep Space 1, launched in 1998 to rendezvous with an asteroid and then a comet. 
+Ion engines are fuelled by xenon gas. The gas atoms are charged by electric guns powered by solar panels and are then expelled from the rear of the spacecraft, delivering a tiny thrust, visible as a ghostly blue glow. 
+Chemical engines burn out after a couple of minutes, whereas an ion engine can push on gently for months or even years, for so long as the Sun shines and the small supply of propellant lasts. 
+SMART-1 travelled 100 million kilometres but used just 80 kilograms (50 litres) of fuel, an extraordinary feat in space exploration standards.
+But unlike the Deep Space mission's essentially straight-line trajectories, SMART-1 had to carry out a complex series of manoeuvres to slowly but relentlessly build up speed. 
+It had to loop again and again around the Earth to gain extra speed yet also juggle with the Moon's gravitational tug, all the time using a tiny engine that delivered the same power as someone picking up an A4 sheet of paper. 
+Camino says the experience was "an adventure," and compared it to navigating a small sailboat buffeted by swirling winds and currents.
+But the tiny thruster needed 14 months for a trip that took Apollo only three days.
+"We have shown that ion propulsion works," Camino says, predicting that this will be the thruster of choice for two ESA missions in the next decade: BepiColombo, to explore Mercury, and Solar Orbiter, which will swoop close to the Sun.
+And it is also likely to be the propulsion for hauling big cargo containers to the Moon to help build the first lunar settlement, or to Mars, to support the first manned mission there, he says.
+Small package
+Other SMART-1 innovations are a new communications system, new-generation solar panels and a package of sensors and scanners that Foing hails as "a miracle of miniaturisation - seven instruments weighing just 19 kilos".
+Weighing as little as a 10th of conventional instruments carried aboard space probes, SMART's x-ray telescope and infrared spectrometer have been carrying out the most detailed map of the Moon's elements and minerals, says Foing.
+SMART-1 has also sought out locations at the lunar poles that are in permanent shade and could be worth exploring if, as some scientists hope, water exists on the Moon or just below its surface.
+
+Your genes only account for 19% of your personality. So don't blame your parents
+Genes shape our health and appearance more than they shape our personality, suggests a new study of thousands of people in a genetically isolated part of the world.
+According to the study, published in the August issue of PLoS Genetics, genetics account for roughly 51% of a person's height, weight and body shape, 25% of cardiovascular function and about 40% of certain blood characteristics, such as sugar and cholesterol levels.
+But genes only account for about 19% of many documented personality traits, such as neuroticism, extraversion, agreeableness and conscientiousness.
+"My personal view is that we have evolved to have very diverse personalities and that, compared to other traits, personality may be much less deterministic than other human characteristics," says Associate Professor Gon&ccedil;alo Abecasis, one of the study's authors.
+"My view is that both genes and environment will play smaller roles than random factors."
+Abecasis, a scientist at the Center for Statistical Genetics at the University of Michigan, and his colleagues examined 6148 people from the Mediterranean island of Sardinia, where many residents are related.
+Roughly 95% of people in the study had Sardinian grandparents, and the test group included 5000 pairs of siblings.
+The researchers believe their study is the largest ever published for the traits they examined.
+The scientists took blood samples, gave physical exams, and asked participants to fill out standard personality questionnaires.
+They also measured liver and thyroid function, electrolyte levels, cholesterol, blood glucose and more.
+Shared DNA
+To figure out the degree to which each trait was affected by genetics, the researchers first calculated the amount of DNA shared by each pair of relatives. 
+For example, the DNA of identical twins is almost 100% identical, siblings average 50% similarity, and uncle-nephew pairs usually have about 25% similarity. Cousins share, on average, about 12.5% of their DNA.
+The researchers then compared this information with the health, weight, personality and other data.
+Computer models matched these traits with relatedness to find how much of each trait appeared to be affected by genetics.
+While the study found genetic effects often determine whether a person will be heavy or thin, the researchers say we cannot always blame our genes for weight problems.
+Dr David Schlessinger, who also worked on the study and is a senior scientist at the National Institute on Aging, says that "lifestyle has led to the current epidemic of obesity".
+"It does appear, however, that some individuals have a genetic constitution that is more resistant to the modern diet and lifestyle than others," Schlessinger adds.
+Personality and disease
+Cross-examination of all of the data revealed that personality traits do not appear to be linked to blood and heart health. For example, anger-prone people don't appear to suffer more heart problems than mellow people do.
+"What is unusual [about the study] ... is its size and integration of a large amount of trait information into the analysis," says Dr Wayne Frankel, senior staff scientist at The Jackson Laboratory in Maine.
+"It is important that the heritability of related traits be considered together, in order to improve the power of gene-identification experiments in future."
+Abecasis and his colleagues next hope to identify the particular genes that are responsible for each of the traits they studied.
+
+Brain chemicals that make you restless and fidgety may also play a role in keeping you lean, a researcher believes
+Thin people's brains may be more sensitive to a naturally occurring chemical that makes them wriggle, jiggle and fidget through the day, an international obesity conference will hear.
+US researcher Associate Professor Catherine Kotz from the Minneapolis Veterans Affairs Medical Center and the University of Minnesota will present her research on the neuropeptide, orexin-A, at an international obesity conference in Sydney this week.
+Previous research has shown that orexin-A, which was only discovered in the last decade, makes us burn energy by stimulating unconscious activity like fidgeting and restlessness.
+Kotz says her study, published online in the American Journal of Physiology, shows orexin-A affects activity in rats when injected into their brains.
+"We injected orexin-A into normal rats and it caused increased movement," she says.
+"When we inject it into lean rats they're very sensitive to it; they really increase their movement. The obese rats don't seem to respond.
+"So that said to us there is some difference in the orexin-A signalling in their brains."
+Underpants study
+Kotz's research grew out of an earlier study by Dr James Levine of the Mayo Clinic.
+In his study Levine put lean and fat people into underwear with built-in sensors that gauged their movement through the day.
+That research, published in the journal Science last year, found that lean people spend an average two hours more a day than their obese counterparts doing unconscious, spontaneous movements such as lifting their arms, jigging a foot or getting up and down.
+"What he found ... is that lean individuals move for two hours more per day than obese individuals," she says.
+"This is activity that was not going to the gym, not exercising." 
+The fidgeters burnt about 350 kilocalories a day through this non-specific movement, the equivalent of a 45 minute brisk walk.
+ Orexin-A on the brain
+When Kotz's team did brain scans on their orexin-A enhanced rats, they found that the lean rats had about double the number of orexin-A receptors than the obese rats, suggesting it's sensitivity, rather than quantity, that counts.
+The difference in receptor number could be because of genetic programming or changes produced by over or under stimulation during life, she says.
+This question is the subject of further study.
+Kotz says while the rat study hasn't been done in humans, our brains also produce orexin-A.
+She says her findings could eventually lead to an anti-obesity treatment, such as a patch, that either increased the number of brain's orexin-A receptors or boost the sensitivity of existing ones.
+
+A wide variety of food helps brushtail possums eat and eat, without overloading their bodies with toxins
+Brushtail possums can tell when they've eaten too much of their favourite snacks, according to new research revealing their uncanny ability to regulate what goes into their mouths.
+Unlike humans, who can pig out on chocolate or hot chips until we make ourselves sick, possums know exactly when they're starting to overload their system with toxins, says researcher Dr Karen Marsh of the Australian National University.
+"They're really good at regulating their intake and knowing exactly how much they can eat," she says of the marsupial herbivores.
+Marsh reports in a recent issue of the journal Ecology that the common brushtail possum (Trichosurus vulpecula) thrives when it eats a wide variety of foods, rather than a limited range.
+The reasons for this have been unclear in the past.
+But Marsh says her study supports one of the leading theories, which suggests that possums are better able to neutralise small amounts of naturally occurring toxins from a variety of foods than a high-toxin load from a single food.
+Food toxins
+Because of its plant-based diet, the brushtail possum eats foods that not only contain nutrients, but potentially toxic by-products.
+It neutralises these in various ways, for example, by oxidising the toxins or converting them into different molecules. 
+If the possum only eats one food it will reach the threshold for that particular toxin faster than if it selects from a wider smorgasbord.
+"Basically they seem to be able to recognise whether toxins are similar or different and feed accordingly," Marsh says.
+"What we think happens is that the toxins activate the emetic pathways in the body so the possums start to feel sick when their detox pathways get saturated."
+Getting rid of toxins
+Marsh tested the hypothesis by identifying various toxin thresholds in the possums and working out how each was eliminated by analysing metabolites in their urine. 
+She then offered the possums a range of foods with similar toxin pathways and a range of foods with different pathways.
+She found the possums ate less when the foods activated similar pathways.
+Marsh says it's important to understand the mechanisms that regulate diet in possums because it can help in their conservation.
+"We want to know what sort of habitat is going to be suitable for them," she says.
+"Can they survive in a habitat that's been degraded and only has one type of plant, or do they really need that mix ... so they can be swapping between the different plants?"
+She says humans should have the same responses to food toxins, but most toxic metabolites have been eliminated from our food, making us more prone to overeating.
+
+Kandinsky's Improvisation 31 (Sea Battle), 1913 . Looks good, but how does it sound?
+The expressionist painter Wassily Kandinsky wanted people to not only see his paintings but to hear them, says a neuroscientist and expert in the condition known as synaesthesia.
+Dr Jamie Ward, a British neuroscientist at University College London (UCL), says the Russian-born French artist knew about synaesthesia, a sensory phenomenon in which one sense can trigger another. 
+For example, synaesthetes report being able to taste music, see sounds or hear images.
+"What Kandinsky wanted to do was for it to appeal to hearing as well," Ward said during a symposium at the British Association for the Advancement of Science Festival of Science. 
+"Kandinsky wanted to make visual art more like music, more abstract. He also hoped that his paintings would be heard by his audiences."
+For example, one synaesthete described a Kandinsky painting as having "a huge splurge of sound ... booming and vulgar", "a mousy little meee sound that translates into 'ohs' and 'ahs'" and shapes that "pop up laughing with a 'whooo'".
+Ward says it's unknown whether Kandinsky experienced synaesthesia himself.
+But the artist certainly knew about the phenomenon, he says.
+Linking vision and sound
+Synaesthetes make up only about one or two in every hundred people, but Ward believes we all link vision and sound unconsciously and we tend to agree on which images match which sounds.
+However, only a tiny minority of us is aware of the crossover in our senses. 
+He hypothesised that most people would be able to link an image by someone with synaesthesia to a particular piece of music upon which the image was based.
+To test the theory Ward conducted a series of experiments where he asked synaesthetes to draw and describe their vision of music played by the New London Orchestra. 
+"We played them musical notes and got them to draw and describe what they see," Ward says. 
+A control group without synaesthesia did the same and a professional artist created animations of the images related to the music.
+When more than 200 people were shown 100 images and asked to choose the animations that best suited the music they consistently selected the images from the synaesthetes. 
+"It's almost as if everybody can appreciate these synaesthetic images even if they don't have synaesthesia," he says.
+"Although information from the world enters our heads via different sensory organs ... once they are in the brain they are intimately connected ... in non-random ways."
+Synaesthesia, which runs in families, is present from birth but not much is known about what actually causes it.
+Ward says studying synaesthesia will help scientists understand how senses and thoughts are linked in out brains. 
+He says the next stage of his research will use brain scans to monitor what happens when synaethetes are shown a Kandinsky painting.
+
+A woman places flowers at the entrance to Australia Zoo after its conservationist patron Steve Irwin, or the Crocodile Hunter, died from a stingray's barb to the heart on Monday
+In death as in life, iconic TV naturalist Steve Irwin captivated millions worldwide and clogged the internet as fans from around the world reacted with disbelief to news the Crocodile Hunter was dead.
+Some websites groaned to a halt within hours of the first reports on Monday that Irwin had been killed by a stingray's barb through his chest in a freak diving accident off Australia's northeast coast.
+Web measurement company Hitwise says Irwin's death was the biggest news event read by Australians on the internet since two Australian miners were trapped by a mine collapse in southern Tasmania state in late April. 
+"We noticed that the website www.crocodilehunter.com increased in popularity quite substantially. It became the number one entertainment personality website in Australia yesterday and in the US it also became the third most popular," says a spokesperson for Hitwise Asia-Pacific.
+Australian news websites struggled to keep up with demand. 
+The ABC's site had to temporarily shut down, posting a notice on Monday that it was experiencing higher than normal traffic. 
+It resumed soon after in a low-bandwidth format to cope with hundreds of thousands of hits. 
+Newspaper websites also wobbled but kept up with demand. 
+A spokesperson for the Sydney Morning Herald says its website experienced a 40% spike in page impressions compared with the previous week's average weekday number of about 500,000. 
+There was also a 70% jump in visitors to its pages, the spokesperson says. 
+That pattern was mirrored around the world, with Irwin's death leading major news websites such as CNN and US and UK newspaper websites, as well as swamping their 'most viewed' and 'most emailed' categories.
+Blogs and internet feedback pages were also awash with postings from shocked readers from around the world, many of them from Americans charmed by Irwin's quirky style and his catchphrase "crikey".
+
+A snapshot within a proton showing a strange quark (red) and its antistrange partner (yellow) together with two up quarks (blue) and a down quark (green)
+Scientists say they've solved a decade-old puzzle about the enigmatic 'strange quark', one of the fundamental building blocks of matter.
+Their findings, published recently in the journal Physical Review Letters, help put our understanding of the universe on a more solid footing.
+Associate Professor Derek Leinweber from the University of Adelaide and colleagues used a combination of supercomputing and physics to study the oddly named particle.
+Strange quarks are one of six different 'flavours' of quark that combine to form protons and neutrons, two of the main components of atoms.
+The others are known as 'up', 'down', 'charm', 'top' and 'bottom' quarks.
+The short-lived strange quark is the most mysterious of them all, Leinweber says.
+It "boils up" inside the positively charged proton and then "simmers back out of existence", he says. 
+Scientists have long pondered exactly how the strange quark contributes to the distribution of charge in the proton, Leinweber says.
+"People have been playing around with these problems for 10 years or more."
+By combining results from real-life experiments with simulations, the Adelaide team, with collaborators at the University of Edinburgh and the Thomas Jefferson National Accelerator Facility in the US, says it has calculated the strange contribution with unprecedented accuracy.
+Those calculations predict that the short-lived strange quarks display an unanticipated level of symmetry in their journey.
+"It's a bit of a surprise," Leinweber says. "There was some idea that the strange quark would be distributed asymmetrically."
+Effective Field Theory
+The research brought together expertise in supercomputing with techniques in a branch of physics called Effective Field Theory, Leinweber says.
+"These are two separate areas which have been used together in a way that no-one else has thought of."
+For the physics world, the findings could have major implications, particularly as experimental results coming from labs around the world are already beginning to confirm the theories of the Australian researchers.
+Now, scientists are considering how to incorporate the results into research at enormous particle accelerator facilities like the Large Hadron Collider buried underground at CERN in Switzerland.
+"Our result presents a huge challenge to experimental physicists in planning the next generation of experiments," says Leinweber. "Billions of dollars are going to be spent based on this result."
+Ultimately, the research is helping scientists understand the universe in greater detail than ever before, Leinweber says. "It's putting our current understanding of our world on a solid foundation."
+
+An inner ear as you have never seen it before University of Sydney's Key Centre for Microscopy and Microanalysis, will report its findings in the journal Acta Oto-Laryngologica.
+The scientists revealed the detailed structure of the inner ear, from a guinea pig, using a new method called x-ray microtomography.
+"It's CT [computed tomography] scanning for microscopy, basically a CT scanner for a microscope," says Jones.
+Like hospital CT scanning, the method images internal structures in 3D using x-rays.
+Structures, like bones, absorb more x-rays and are more visible than those that absorb less.
+The 3D image is built up by taking a series of 'slices' of the solid object.
+But x-ray microtomography can take many more slices that a hospital CT scanner.
+This provides much higher resolution, allowing scientists to image the delicately thin structures of the inner ear.
+The image the scientists generated shows the stapes (red) the saccular macula (yellow) and the utricular macula (blue).
+It also shows the coils of the cochlea and the fluid-filled semicircular canals that help an animal keep balance.
+"This structure is actually embedded in the most dense bone in the body, the temporal bone, and normal hospital medical CT doesn't have enough resolution to see these," says Jones.
+Secrets of an ancient eyeball
+One of the first studies Jones was involved in that used the new technique was the imaging of 410 million-year-old fossilised fish eyeballs.
+The project, carried out with palaeontologist Dr Carole Burrow from the University of Queensland, was the first use of x-ray microtomography to investigate small vertebrate fossils.
+
+Methane bubbles trapped in lake ice in October
+Fears that retreating permafrost is accelerating climate change have been strengthened by a new study that says emissions of the greenhouse gas methane are soaring in northern Siberia.
+In a complex cycle, permafrost melts at the edges of lakes that previously were iced over year-round, according to the research led by Dr Katey Walter of the University of Alaska at Fairbanks.
+Organic material, the remains of rotted plants and long-dead animals, then subsides into the lake from the soil, slides to the lake bottom and decomposes to form methane.
+Eventually, during a thaw, this methane bubbles to the surface and is released into the atmosphere. 
+In the first major study into the bubbling phenomenon, or ebullition, Walter's team believes that current estimates of methane released from wetlands between latitudes 65 and 70&deg; north should be upgraded by 10-63%.
+"Ebullition from Siberian thaw lakes is a large and increasing source of atmospheric [methane] as Siberian thaw lakes continue to expand," warns the study, published today in the journal Nature.
+Between 1974 and 2000, a period that matches figures for local warming, the spread of thaw lakes caused methane emissions in Siberia to rise by 58%, it says.
+The greenhouse gas methane comes from natural sources such as agriculture, decomposing vegetation and marshland. 
+One worry is what scientists called a "positive feedback" from billions of tonnes of stored methane that is locked in the ground and under frozen lakes in  Canada and Siberia. 
+This scenario, in essence, is a vicious circle, scientists say: global warming warms up the permafrost, which releases the trapped methane and this in turn adds to the greenhouse effect. 
+Volume for volume, methane is 21 times more effective at trapping solar heat respectively than carbon dioxide.
+By itself, methane accounts for a fifth of the man-made greenhouse effect of the past 200 years, scientists say.
+
+Playing against other gamers may help to build informal connections and expose people to multiple world views
+Gaming can be a sociable experience, according to a new study that questions the myth of the lone gamer sitting at the computer, disconnected from society.
+The US study says games involving multiple players can act like informal gathering places like pubs and coffee shops, so can boost the players' social connections. 
+Assistant Professor Constance Steinkuehler of the University of Wisconsin-Madison and Assistant Professor Dmitri Williams of the University of Illinois at Urbana-Champaign looked at people playing so-called massively multiplayer online games (MMOs).
+"By providing spaces for social interaction and relationships beyond the workplace and home, MMOs have the capacity to function as one form of a new 'third space' for informal sociability," the researchers write. 
+While such sociability won't offer "deep emotional support", they add, it has the benefit of exposing players to a wide range of viewpoints and a more diverse social environment. 
+The effects of the internet on society are still being debated, the researchers note in an article in the Journal of Computer-Mediated Communication.
+Some say it allows people to build connections and communities, while others say such virtual links are just a poor substitute for the real thing. 
+The researchers sought to investigate the role of MMOs, in which players inhabit 'avatars' or on-screen representations of characters within virtual worlds and chat with other players by text or voice, in players' social lives. 
+They studied whether one game, Asheron's Call I and II, built players' "social capital" by dividing 750 people into game-playing and non-playing groups. 
+They also conducted a two-year study of the activities and perceptions of a group of people playing the game Lineage. 
+Steinkuehler and Williams conclude that the games helped players gather a type of social capital known as bridging, which involves making informal connections with others, while they didn't generally help people build stronger social bonds.
+Such weaker social links are important, the researchers say, because they offer players the opportunity to be exposed to diverse world views that they may not encounter in the real world. 
+But players who did become more deeply involved in the games did run the risk of having virtual relationships replace real-life ones, the researchers note. However, to see these online communities as an entirely bad thing is short-sighted, they say.
+"To argue that MMO game play is isolated and passive media consumption in place of informal social engagement is to ignore the nature of what participants actually do behind the computer screen," they state. 
+"In the case of MMOs, game play is more akin to playing five-person poker in a neighbourhood tavern that is accessible from your own living room."
+
+Chimp or lollipop man? Dominant chimps look both ways to see if the road's clear before shepherding other chimps across
+Adult male chimpanzees act like school lollipop men by leading smaller chimps across roads that dissect their forest habitats, according to a new study.
+The finding demonstrates that chimps display concern for family and friends and will risk their own safety to ensure the welfare of others.
+Scientists now believe such ability for care and consideration is present in certain primates, and not just humans.
+"I think that we would definitely see this kind of behaviour in other great ape species, and different populations may reveal cultural differences in protective orderings," says Kimberley Hockings, lead author of the study, which is published in the journal Current Biology.
+Hockings, a researcher at the University of Stirling in Scotland, and colleagues observed a group of wild chimps in Bossou, Guinea, West Africa.
+The chimp group consisted of three adult males, five adult females, three juveniles and one infant.
+Two roads dissect the chimps' forest homeland. The first is a narrow road used by pedestrians, while the second is wider and carries trucks, motorbikes, cars, as well as pedestrians.
+The scientists analysed 19 instances where the chimpanzees crossed the two roads.
+In each instance, an adult male, often the alpha male named Yolo, would stand at the edge of the road. He then would carefully look left and right, then motion with an arm.
+At that point, the other chimps formed themselves into an ordered line and followed behind. The order nearly always consisted of adult males first with females, juveniles and the infant second. The leader, or another adult male, would then wait at the end of the line to assist the littlest ones.
+When crossing the heavier traffic road, the second ranked male, Foaf, would continue to scan for vehicles and people while the elderly third male, Tua, and the alpha female took the lead. 
+The researchers noted that the female would move into the more forward, leader position when the degree of crossing risk increased.
+"They tend to travel in such ordered lines in risky situations such as road crossing and crop raiding," says Hockings.
+"Depending on the situation, when moving through the forest, it is much more common that the chimpanzees are spread out."
+Dr Klaus Zuberb&uuml;hler is a University of St Andrews scientist who conducts research on the cognitive capacities of non-human primates. The Scotland-based scientist calls the findings "amazing".
+"What's perhaps most striking is that Kimberly's research shows that these free-ranging chimpanzees are not indifferent to the welfare of other group members, in contrast to previous findings reported from captive chimpanzees," Zuberb&uuml;hler says. 
+"They appear to have an understanding of other group members' vulnerability and they take action in response to this knowledge.
+"It also highlights the importance of studying the cognitive capacities of primates in the wild. The majority of research on chimpanzee intelligence is currently conducted in highly deprived lab situations, and, perhaps unsurprisingly, individuals often show little or no interest in engaging in cooperative or altruistic acts."
+Hockings hopes future research will determine similar progression orders in other great ape populations, which could reveal how human social organisation probably emerged in our distant primate ancestors.
+
+The coral reef pygmy goby, Eviota sigillata, swims its way into the record books
+Life on the Great Barrier Reef is fast and furious for the coral reef pygmy goby, the world's shortest-living fish whose entire existence lasts no longer than two months.
+The pygmy goby's record-breaking status was confirmed this week by Guinness World Records. Not only is it the fastest living fish, it has the shortest life span of any creature with a backbone known to science.
+The tiny fish spend their first three weeks as larvae in the open ocean before they settle on the reef.
+They then mature within two weeks and have a maximum adult lifespan of just three and a half weeks, says Professor David Bellwood from James Cook University and ARC Centre of Excellence for Coral Reef Studies.
+In total, they live 59 days, "and that's the maximum", Bellwood says.
+"It's like taking a 90 year old woman and saying that's how long humans live. Most of them don't make it there."
+Bellwood and his colleague Martial Depczynski first reported the goby's remarkable life span in the journal Current Biology last year, and then submitted it to Guiness for world record scrutiny.
+They figured out the life span of the fish by examining small bones in their ears called otoliths, which grow as they age.
+"Each day, pygmy gobies lay down a new ring in their otoliths, much as a tree does for each year," Bellwood says.
+The results were a complete surprise.
+"We were just stunned," Bellwood says. "We thought at first it must have been a mistake, but we went back again and again and confirmed it."
+Pygmy gobies (Eviota sigillata) are found on the Great Barrier Reef and other reefs in the Pacific and Indian oceans.
+During their three-weeks of sexual maturity, the fish produce just three clutches of eggs. To help ensure they survive, the male goby stands guard, fanning the eggs with his fins while they are incubating.
+The fast and furious lifestyle of the fish is probably an evolutionary response to the fact that they have so many predators on the reef, the scientists say.
+For small species living in places where their life expectancy is low, evolution often favours a 'live fast, die young' strategy.
+"It's just a case of reproduce like mad before you die," says Bellwood.
+
+Common brown snakes like this one surprised the scientists by producing higher levels of venom than anyone had seen before
+Australian snakes are delivering more venom than we realise, according to researchers who say this may force us to rethink how we treat snakebites. 
+The poisonous Australian brown snake is one of the surprise packages, producing what lead researcher Peter Mirtschin describes as "spectacular" yields of venom. 
+Mirtschin, managing director of the company Venom Supplies and adjunct research fellow at the University of South Australia, and colleagues publish their findings online in the journal Ecotoxicology.
+Dr Bryan Grieg Fry, of the Australian Venom Research Unit at the University of Melbourne, says the study is "of huge importance", particularly in relation to brown snakes and current antivenom guidelines.
+"The findings have huge clinical implications. The brown snake is the most common cause of snakebite in Australia and the most common cause of death by snakebite in Australia," says Fry, who wasn't involved in the research.
+"The key to antivenom is to get it in early and to get in the proper amounts. A big amount [given] early means less overall total, as well as a better clinical outcome."
+"[These findings] can dramatically influence the amount of antivenom needed."
+He says the findings are "definitely" strong enough to change clinical practice in Australia.
+Milking snakes
+The researchers milked 33 dangerous species of snakes native and non-native to Australia numerous times over a six-year period from 1999 to 2005. 
+Then they averaged the yield, or the average amount of venom a snake produces when it is milked, by each snake type.
+The team found that snakes from the Pseudonaja genus, including the Queensland and South Australian common brown snake, yielded higher than previously published amounts of venom.
+"In certain individuals we found quite spectacular yields. If you had a bite by one of those you'd be in real trouble," says Mirtschin.
+Higher percentage solids were also obtained from venoms from four cobra species from the Naja genus and the Pseudechis (king brown) genus.
+Snake venom comprises salts, water, enzymes, proteins and other macromolecular and smaller organic and inorganic compounds.
+Venom yield is traditionally measured and compared in its dried powder form, where the water is removed, leaving the remaining solids.
+The findings have led researchers to call for a rethink on current volumes and dosages of antivenom serums. 
+"If you are giving antivenom then maybe the vial size of the antivenom should be increased. Or at least the number of vials that are recommended as the initial dose [be increased]," Mirtschin says.
+
+When the researchers asked the woman to imagine she was playing tennis, her brain scan lit up in virtually the same places as the brains of healthy volunteers asked to do the same thing
+Brain scans of a woman who has been in a vegetative state for five months show her imagining playing tennis and responding to commands, researchers report.
+They say their study, published today in the journal Science, shows the woman was conscious despite her coma-like state, although several experts disagree.
+The researchers stress that the study is unlikely to shed light on issues such as the case of Terri Schiavo, a Florida woman who spent 15 years in a persistent vegetative state and was allowed to die in March 2005 after a long court battle.
+Dr Adrian Owen, a neuroscientist at the University of Cambridge and colleagues in the UK and Belgium, used functional magnetic resonance imaging, or fMRI, to look at the woman's brain in action. 
+The 23-year-old woman, who was injured in a car accident, had been unresponsive, unable to communicate, and met the clinical criteria for a vegetative state, the researchers say. 
+They looked at her brain function when listening to sentences such as, "There was milk and sugar in his coffee." The brain scan lit up in very similar ways to those seen in healthy volunteers, Owen's team found.
+The researchers then asked the woman to imagine certain acts. 
+"One task involved imagining playing a game of tennis and the other involved imagining visiting all of the rooms of her house, starting from the front door," the researchers write.
+Her scan lit up in virtually the same places as the brains of the healthy volunteers asked to do the same thing. 
+"These results confirm that ... this patient retained the ability to understand spoken commands and to respond to them through her brain activity, rather than through speech or movement," the researchers write. 
+She also clearly intended to cooperate, which "confirmed beyond any doubt that she was consciously aware of herself and her surroundings", they write. 
+"This is unlikely the case for all vegetative patients," Owen's team cautions in its report.
+Experts note the woman had relatively little brain damage, and say traumatic brain injury often heals better than injury caused by stroke or heart attack such as Schiavo suffered.
+Schiavo also had been in her state for far longer than the UK woman, allowing for severe deterioration of her brain.
+Dr Ross Zafonte, a brain rehabilitation expert at the University of Pittsburgh School of Medicine, says the study shows a unique way of assessing brain function using scans.
+"They raise a whole issue regarding consciousness and how we use this term," Zafonte says. 
+"Is she just a rare bird? Will we see this on a more common basis?" 
+Other brain experts are sceptical. 
+"If this patient is actually conscious, why wouldn't she be able to engage in intentional overt motor acts, given that she had not suffered functional or structural lesion of the motor pathways?" asks Dr Lionel Naccache of France's INSERM research institute in a commentary published with the report. 
+He says the patient apparently has "a rich mental life, including auditory language processing and the ability to perform mental imagery tasks". 
+The study points to a need to develop better scans to assess a patient's brain status, Naccache says. 
+Dr Paul Matthews, a neuroscientist at Imperial College London and University of Oxford, says the study does not demonstrate consciousness.
+"Response to stimuli, even complex linguistic stimuli, does not provide evidence of a 'decision' to respond. Withdrawal from an unexpected painful pin prick does not represent a 'decision' to respond," he says.
+
+Could hydrogen sulfide gas from the river have killed Dr Bogle and Mrs Chandler?
+New evidence may support the idea that 'rotten egg gas' from a polluted river was to blame for two of the most mysterious deaths in Australian history.
+Evidence aired in an ABC TV documentary this week suggests a concentrated cloud of hydrogen sulfide killed physicist Dr Gilbert Bogle and Mrs Margaret Chandler.
+But some toxicologists remain sceptical that the gas was behind the deaths of the two lovers, whose bodies were found by the banks of Sydney's Lane Cover River in 1963.
+At the time some suspected they were killed by a rapidly acting poison.
+Yet the investigation, which included help from the FBI and New Scotland Yard, could find no cause of death, motive or killer.
+Many suspected Margaret Chandler's husband Geoffrey. But the documentary Who killed Dr Bogle and Mrs Chandler? resurrects the hydrogen sulfide theory, a notion first discounted by police investigators in 1971.
+According to the theory, hydrogen sulfide bubbling up from the river mud in the still early morning air had became trapped in a hollow where the lovers lay in embrace.
+The gas had come mainly from industrial waste that had been dumped into the river over the past 60 years, and hydrogen sulfide from sewage in the river.
+US forensic toxicologist Dr Thomas Milby told the film-maker that hydrogen sulfide gas can be fatal in high doses and his reading of the autopsy reports convinced him the gas was the culprit.
+"The probabilities were [that] it was an inhaled gas, as opposed to a pill or something like that," he says.
+Milby also commented on analyses of blood samples taken from the two victims during the investigations. These found a bluish tinge in both samples, which he says supports the hydrogen sulfide theory.
+"I saw nothing in either report that would, in my opinion, exclude the possibility of hydrogen sulfide as being the culprit that killed them."
+Sceptical
+But at least two Australian experts are not so sure about the theory.
+"As a healthy sceptic I'd say 'interesting theory' but why didn't they smell [the gas]? Because it's pretty disgusting," says forensic pathologist Dr Christopher Lawrence who is with the Tasmanian health department.
+"Also, were the tests taken in a way that you could rely on the results?"
+He says while hydrogen sulfide could discolour the blood by interacting with haemoglobin any blood tests would needed to have been carried out very shortly after the deaths.
+
+Wreaths laid for Steve Irwin who died from a stingray's barb to the heart while filming a documentary in North Queensland
+This week's mass grieving in response to the death of Australian crocodile hunter Steve Irwin is part of a fairly recent phenomenon dependent on the mass media, say experts.
+But how do we make sense of this public grieving for the loss of someone most have never met?
+We generally think of grief as being associated with the loss of people we're very close to, like a family member, says psychologist Grant Brecht, of the Australian Psychological Society.
+But he says we can feel close to someone we have never met if we come to know and like them through their appearances in the media. 
+"We conjure up in our own mind feelings and thoughts about what that person would be like," says Brecht.
+And when they die we respond as if we did in fact know them.
+"We can experience grief almost at the same level as we may well do with a family member," says Brecht.
+"People would have felt an affinity with Steve," he says. "He was a bit of an Australian icon, a bit of an Australian larrikin, someone who seemed to have quite an affinity with animals, which most of us would respect."
+Brecht says the mourning is a healthy part of dealing with the feeling of loss.
+While most of us will remember the spontaneous outpourings exhibited after the death of Princess Diana, grieving hasn't always been such a public affair.
+A recent phenomenon
+Australian National University historian Professor Pat Jalland says mass public grieving has really only taken off since the 1970s.
+"Had the equivalent of Princess Diana died 40 years earlier I can guarantee it would not have resulted in anything like what happened," she says.
+Jalland says the last period in history when grieving was an accepted activity was during the 19th century, before the advent of mass media.
+At this time death claimed many infant lives and grieving occurred through religious rituals.
+But between 1918 and the 1970s public grieving was suppressed, says Jalland.
+In part this was helped by a decline in infant mortality, which meant death mainly happened in old age and behind closed doors at home and, eventually, in hospital.
+Silence about death
+The suppression of grief was also helped by a decline in religious ritual and by a period of major wars in which soldiers, and by implication all of us, were expected to bear death with stoicism, says Jalland.
+"The two world wars created a massive overload of death and sorrow which induced what Freud and others call death denial - a silence about death," she says.
+"The emotional responses were suppressed."
+At this time media coverage of sudden and tragic deaths were very factual and lacked the personal stories that are common today, says Jalland.
+But she says all that changed in the 1970s when there was a huge cultural shift towards more open displays of emotion.
+This shift was encouraged by the women's and gay liberation movements, says Jalland, and by psychologists like Elisabeth Kubler-Ross who encouraged open discussion about death and dying.
+And it was encouraged by the mass media, which showed grief as a normal response to tragedy by reporting the personal stories of those involved.
+Secular spirituality
+Dr David Ritchie of Deakin University, who has a special interest in grief education, says the good side of mass media facilitated grief is that it gives people permission to grieve.
+He says this is important in a society where people seldom die at home, there are few rituals around death and people's main experience of death is through the media.
+"The idea of death as part of the life cycle is really foreign," says Ritchie, who is also on the management committee of the Australian Centre for Grief and Bereavement.
+Ritchie says spontaneous outpourings of grief in the company of strangers helps people make sense of the shocking nature of sudden death. 
+Making shrines out of flowers, photos, artwork and poetry, lighting candles and sharing stories about the person who has died all helps to make people feel connected and empowered, says Ritchie.
+"It's part of a secular spirituality".
+But Ritchie doesn't see mass public grieving as anything like the grief of a close family member.
+"We can always see Steve Irwin by looking at the films," he says. 
+"We can always press the rewind button or put the tape back in again because that's how we knew him."
+It will be very different for his family, says Ritchie.
+And he says each person experiences grief differently and the "one size fits all" version sanctioned by the mass media could lead to inauthentic experiences of grief.
+
+Most people who had died from bird flu virus in the Vietnamese study had the virus in their blood, suggesting it could have been transported out of the respiratory tract
+The H5N1 bird flu virus replicates far more aggressively in people than common human flu viruses, a study of patients in Vietnam has found, offering further insight as to why the virus is so deadly. 
+The study, published online in the journal Nature Medicine, also found that the virus gets into the blood stream of many of the humans it kills, which means the virus can spread to other parts of the body.
+Dr Menno de Jong, of the Oxford University Clinical Research Unit at Vietnam's Hospital for Tropical Diseases in Ho Chi Minh City, says that the unusually high viral loads trigger intense cytokine responses, an immune system overreaction that can be fatal.
+Cytokines are proteins in the immune system that fight off intruders such as bacteria and viruses. 
+"During H5N1 infection, the [cytokine] response seems to be very, very intense. Cytokines want to get rid of this intruder but if you have very high levels of cytokines, it can also damage the body ... it can be directed against your own cells and organs," says de Jong.
+The study involved 18 people infected with H5N1 and eight with human flu in 2004 and 2005 in Vietnam.
+Scientists found far higher viral loads in the nose and throats of those infected with bird flu than human flu. 
+Thirteen of those infected with H5N1 died and the virus was found in the blood of at least nine of them, suggesting it could have been transported out of the respiratory tract. 
+The virus was also found in the rectums of most of those with H5N1, suggesting it could have spread through the blood stream into the gastrointestinal tract. 
+Those with common flu had no virus in their blood or rectum. No one died in that group. 
+"The fatal outcome of H5N1 infections seems to be associated with high levels of replication of the virus and also the detection of the virus in the blood," says de Jong. 
+The team was able to draw a connection between those who were most ill and the level of cytokines found in them. 
+"We found that levels of cytokines were much higher in H5N1 patients than in the human flu cases. Again, the highest levels of cytokines were found in those who died of H5N1," he says. 
+"The high levels of the virus triggered an overwhelming inflammatory response that contributed to lung dysfunction and eventual death." 
+De Jong highlights the need to stop the virus replicating. 
+"What's important is to stop the replication as soon as possible, so you prevent damage to the lungs and prevent the inflammatory response to the virus," he says. 
+But he says that early diagnosis is a challenge, especially in remote places where health services are not readily available.
+
+Could graffiti be a sign of something more serious than teen rebellion?
+Teens who get involved in graffiti 'tagging' may be showing early symptoms of a personality disorder, an Australian psychiatrist says.
+Professor Graham Martin, director of child and adolescent psychiatry at the University of Queensland and colleagues, studied more than 2600 people aged 13. 
+He says the study, presented at an international child and adolescent mental health conference in Melbourne this week, found that teens who graffiti "are significantly different to those who do not graffiti".
+"They satisfy the ... criteria for conduct disorder and or delinquency and later down the track a number of these young people go on to antisocial behaviour personality disorder," he says.
+"These young people ... were very antisocial on a range of other factors. They weren't just mildly conduct disordered, they were scoring to the extreme range of antisocial behaviour."
+Martin says the findings of the study show that conventional methods of handling young graffiti offenders, such as dealing with them under the legal system, are doomed to failure.
+But he says the good news is that with intensive individual, family and community therapy it's possible to put people back on track.
+"Graffiti may be one gateway into working with young people to assist them to find a new direction," he says.
+"It may be extending their creative skills or just sitting down with them and saying, listen you've had a bit of a shit life haven't you?"
+Subtexts of graffiti
+Martin says tagging conveys a number of messages, from saying "hello, I'm here" to being a territorial marker and an expression of rage against authority.
+He says the study found adolescent graffitists had done around six to eight other acts, such as setting fires, beating people up and stealing.
+They also had higher rates of drug use, academic failure, physical and sexual abuse, depression, anxiety and suicidal thoughts.
+Of the teenagers studied, about 12% of boys and almost 11% of girls had done some graffiti. 
+It may even be possible to pick a future graffitist, Martin says, underlining the importance of early intervention.
+"You can pick many of these young people somewhere around the age of three," he says.
+"The average kindergarten teacher will tell you, I don't like that child, I can't work with them, they spit at me, they spit at the other kids, they hit people, they won't learn.
+"You can certainly predict which ones will go on to antisocial behaviour, and within that graffiti is going to be one of the things that stands out."
+
+One critic is concerned that the new packaging will make sugary soft drinks more appealing to children
+Can't decide which soft drink to buy? Help may be at hand with a new drinks bottle that has flavour buttons to give you multiple choices in one container.
+The programmable bottle, designed by a US company, could also improve choices for shampoos, sauces, paints and perfumes, while reducing manufacturing costs and taking up less shelf space, its developers say.
+"The idea here is that the company can launch more variety, but distribute less product around the country," says Tom Woolf, president and founder of Ipifini, based in Sudbury, Massachusetts.
+The concept came from software that Woolf invented, called Innovation Engine, which pulls knowledge from databases to systematically help the user improve an existing product or come up with a new idea.
+When it comes to improving soft drinks, food manufacturers appeal to broad tastes. For instance, brand colas come in several flavours.
+Building and operating several factory lines to accommodate each flavour is more expensive than using just one.
+Distributing the variety of flavours is also a challenge. Each store needs more of one flavour than another, which can make ordering and stocking an inventory nightmare.
+And although large stores may be able to accommodate all flavours, small stores usually have limited shelf space.
+But the programmable bottle would require just one factory line to dispense the base flavour, such as cola. Several different flavours would be locked in sealed, plastic buttons around the edge of the bottle neck.
+A customer could choose cherry cola, for example, by pressing the cherry button, squirting the flavour into the drink. To get cherry vanilla, both cherry and vanilla flavour buttons could be pressed.
+Other products, such as paint, perfume, and shampoos could also offer customised colours, scents or conditioning formulas.
+Drink or toy?
+But the bottle may have some unintentional consequences for children.
+"It's clear to me that it will be seen as a toy," says Diane Levin, professor of education at Wheelock College in Boston, and an expert in how popular culture affects child development.
+"Any child looking at that bottle will want to play with the buttons," she says, pointing out that if the bottle is used for sugary soft drinks, it has the potential for luring kids into seeing junk food as something to play with.
+But Woolf disagrees. "I don't think it's going to change how many people drink sugared drinks or non-sugared drinks," he says.
+According to Woolf, the first use of the bottle will be for flavoured, sugarless water.
+Ipifini has licenced the technology to a company that sells flavours worldwide.
+
+Sudoku tests your brain's neural circuits, especially ones involved in memory
+No wonder Sudoku puzzles give your brain a good work-out. Scientists say solving them depends on neural pathways that even the most powerful computers can't replicate.
+They say that by studying how people solve the puzzles, we might be able to develop more intelligent and brain-like computers.
+In a paper published on the arXiv physics website, Professor John Hopfield of Princeton University explores the unique brain processes we use when playing Sudoku.
+This mathematical puzzle involves filling in a grid of 81 squares with varying combinations of the numbers one to nine, something that sounds simple but can be diabolically hard.
+To crack Sudoku our brains use a unique set of neural pathways known as associative memory, Hopfield says, which enables us to discover a pattern from a partial clue.
+Although computers can store large amounts of information and process it at great speed, they aren't yet capable of sophisticated associative memory.
+Hopfield provides an algorithm of associative memory in his paper, which he says could be implemented in silicon chips.
+Patterns
+We all recognise the basic pattern of counting from one to nine, yet the task of completing a Sudoku puzzle is confounded because of the large number of possible permutations of this pattern.
+But every time we put the right number in the right place it provides us with a clue, which reduces the number of permutations.
+In this way Sudoku is based on a combination of logic and intelligent guesswork based on our abilities of associative memory, Hopfield says.
+"In neural terms, the signals developed  ... can produce a strong and reasonably accurate feeling of correctness of the item retrieved," Hopfield says.
+"This fact may account for our strong psychological feeling of 'right' or 'wrong' when we retrieve a memory from a minimal clue."
+Brains versus computers
+Associate Professor Andrew Paplinski is an Australian computer scientist who specialises in neural networks at Monash University in Melbourne.
+He says the process described in Hopfield's paper helps us to remember a name from a fragment or recognise a partially obscured face.
+He says applying Hopfield's model could lead to more accurate facial recognition computer technology.
+Being able to mimic associative memory would give computers "extreme robustness of pattern recognition", Paplinski says.
+For example, for a computer to recognise a partially visible face it would first have to recognise that the face is obscured, then that it is a face, and then it would have to find a match.
+"To answer all these questions takes an enormous amount of computation," he says.
+He says we can do this in a fraction of a second in a slow computer like our brain. So there were would be significant implications if we can figure out how this is done and design computers that can replicate it.
+
+Not breathing while training with weights can increase the pressure on your eyes, potentially leading to glaucoma
+Holding your breath while you're weight lifting can increase the risk of developing eye disease and potentially blindness, a study says.
+Weight lifters who don't breathe while they're training can experience temporary increases in eye pressure that could heighten the risk of developing glaucoma, according to a study published in the Archives of Ophthalmology this week.
+Researchers at the Catholic University of Brasilia in Brazil measured the intraocular pressure of 30 men aged 18 to 40 during a bench press session.
+"We tested subjects performing a bench press, a popular exercise in [gyms]," the researchers say.
+A bench press is done by lying on your back on a bench and raising a bar bell above your chest.
+The researchers measured eye pressure while the subjects were holding their breath and compared this to when they were exhaling.
+The study found that eye pressure increased more if they were holding their breath than if they were breathing. 
+According to the findings, 90% of subjects had an increase in eye pressure when they didn't exhale while doing the bench presses, compared with 62% who did.
+"The mean intraocular pressure increased significantly during weight lifting," the researchers conclude.
+"Prolonged weightlifting could be a potential risk factor for the development or progression of glaucoma."
+Musicians also at risk
+Glaucoma is a condition associated with pressure on the eye. The pressure slowly destroys the optic nerve at the back of the eye, causing vision impairment and possible blindness.
+The researchers say the form of glaucoma relevant to weight lifters is known as normal-tension, or low-tension glaucoma.
+This is most common in people who experience frequent changes in eye pressure.
+The disease can be hard to pick up because it develops even though eye pressure is normal when it's measured in routine checks.
+It's also more common among people who play high-resistance wind instruments or those with asthma or intestinal or urinary tract blockages.
+"Intermittent intraocular pressure increases during weightlifting should be suspected in patients with normal tension glaucoma who perform such exercises," the authors conclude.
+
+Computer-generated image of TrES-2 as seen from the night side, with its host star in the distance
+Astronomers using a tiny amateur-class telescope and off-the-shelf camera lenses have found a Jupiter-sized planet orbiting a star 500 light-years from Earth.
+The planet, called TrES-2, is the first to be found in this particular field of view, known as the Kepler Field.
+The discovery is the second for a network called the Trans-Atlantic Exoplanet Survey, or TrES, which taps small telescopes in California, Arizona and the Canary Islands to hunt for planets outside our solar system.
+The team looks for planets that pass in front of their parent stars, relative to the view from Earth.
+As the planets transit, they slightly dim the total amount of visible light that radiates from the star, as seen from Earth.
+By observing the star over a period of weeks or months, astronomers can detect if there are any objects that temporarily and regularly block a bit of sunlight.
+"It's really difficult to make these measurements," says Francis O'Donovan, a graduate student at the California Institute of Technology and the lead author of a paper slated to appear in the Astrophysical Journal.
+TrES-2 is a gas giant, similar to Jupiter but somewhat bigger and more massive.
+But unlike Jupiter, TrES-2 is very close to its parent star and very hot. The planet dims its parent star's light by only 1.5% as it passes around every 2.5 days.
+The astronomers also had to rule out other possible explanations for the dimming, such as a partner star gravitationally locked in orbit with the target star, called GSC 03549-02811 and located in the constellation Draco.
+Finally after months of work, the observation was confirmed by a large 10 metre telescope at the Keck Observatory in Hawaii.
+"All our hard work was made worthwhile when we saw the results," O'Donovan says, who hopes to parlay his discovery into a doctorate degree in astronomy.
+O'Donovan's goal is to find Earth-sized planets beyond our solar system, but for that he will need much more powerful telescopes. He may return to the TrES discovery in the future.
+The planet is the first found in the Kepler Field, a part of the sky that will be the sole target of a NASA telescope slated for launch in 2008.
+The Kepler Space Telescope is designed to find Earth-like planets in orbits that favour the development of life.
+The TrES network involves the Sleuth telescope at Caltech's Palomar Observatory in San Diego County, the Planet Search Survey Telescope at Lowell Observatory near Flagstaff, Arizona, and the Stellar Astrophysics and Research on Exoplanets (STARE) telescope in the Canary Islands.
+A new larger telescope, funded by the Discovery Channel, is under development at Lowell that will also be used for hunting extrasolar planets.
+
+Scientists have found what's thought to be the first link between storms on Earth and turbulence in space
+Thunderstorms on Earth can lead to storms in the outer reaches of the atmosphere that disrupt radio transmissions and other electronic communications, US researchers say.
+The research, which is published in a recent issue of the journal Geophysical Research Letters, is believed to be the first time researchers have found a global link between weather on Earth and in space.
+The discovery could lead to more reliable global-positioning satellite (GPS) navigation and short-wave radio transmissions by improving forecasts of high-altitude disturbances that can disrupt them, says University of California, Berkeley researcher Dr Thomas Immel. 
+Using data from NASA satellites, Immel and other researchers discovered that thunderstorms over South America, Africa and Southeast Asia can create turbulence above the equator in part of the upper atmosphere known as the ionosphere.
+The ionosphere is formed from solar x-rays and ultraviolet light, which break apart atoms and molecules in the upper atomosphere, creating a layer of electrically charged gas known as plasma.
+The densest part of the ionosphere forms two bands of plasma close to the equator at a hight of about 400 kilometres.
+These plasma bands are far too thin to be directly affected by wind from thunderstorms. But the researchers found that the wind can shape the plasma bands by generating electricity in the layer of atmosphere below them. 
+Three of the densest sections of plasma were located directly above areas with frequent thunderstorms: the Amazon Basin in South America, the Congo Basin in Africa, and Indonesia.
+But the researchers found another dense section of plasma above the Pacific Ocean, far from thunderstorm zones.
+They say this is evidence that tropical thunderstorms have a global influence. 
+That may explain why the ionosphere above North America is more turbulent than other areas, disrupting radio transmissions that travel through it. 
+"We now know that accurate predictions of ionospheric disturbances have to incorporate this effect from tropical weather," Immel says. 
+Researchers now hope to determine if the plasma bands shift with the seasons, or during large events like hurricanes.
+
+The return of a fragment of the Parthenon to Greece shouldn't set a precedent for the repatriation of other museum pieces, says the University of Heidelberg
+The battle over fragments taken from Greece's Parthenon has resurfaced with the return of a small piece of the ancient monument by a German university.
+The fragment consists of a foot, carved from marble, which was taken nearly 200 years ago from the northern frieze.
+Greek officials hailed the fragment's recent return as an important step toward the return of other fragments of the 5th century BC building, many of which are kept at the British Museum in London.
+The relief sculpture, which measures about 7 by 12 centimetres, had been held at the University of Heidelberg for more than 130 years and first appeared in the university's inventory in 1871.
+It was probably taken as a souvenir by a German visitor to Greece. 
+"This is a historic day. For the first time in almost 200 years, a precious piece of the Parthenon abroad is put in its original place," Greek culture minister Giorgos Voulgarakis said as the sculpture was handed over by the university's vice-rector Professor Angelos Chaniotis.
+The University of Heidelberg says the decision to return the fragment was "guided by the scholarly aim of promoting the unification of the Parthenon as a unique monument of world culture".
+Voulgarakis hails the repatriation of the small fragment not only as a highly symbolic act, but as an unprecedented move in favour of the reunification of Greece's artistic heritage.
+"For the first time, the silent agreement among museums in possession of Parthenon sculptures has been broken," he says.
+Archaeological artefacts scattered
+The fearless horsemen, sprightly youths, lounging deities, belligerent centaurs and expressive horses carved by Phidias in the 5th century BC are scattered throughout several European museums, including the Louvre in Paris. But the bulk of the marbles are kept in London's British Museum.
+Greece contends that the 17 figures and 56 panels on display there were stolen in 1801 by Lord Elgin, British ambassador to the Ottoman Empire. The works have since become known as the Elgin marbles.
+Britain says that Lord Elgin had permission from the ruling Turkish authorities to take them.
+The British also contend that the marbles have received better treatment at the British Museum, where they are safe from the polluted Athens air, which has damaged other Greek treasures.
+Voulgarakis remarks that a space in the new Acropolis museum, which is due to be completed next year, has been reserved for the Parthenon sculptures.
+"The demand for unification of the Parthenon sculptures originates exclusively by moral reasons and not by a nationalistic obsession," he says.
+A precedent?
+The University of Heidelberg stresses that the transfer of the fragment is "a special case that should not be used as a precedent for other monuments and works of art".
+But the German gesture is likely to cause controversy among museums worldwide.
+In 2002, when negotiations were under way to return a Parthenon fragment held at the Salinas Regional Archaeological Museum in Palermo, Sicily, directors of several major museums around the world deplored the move, saying that it could destabilise the entire museum system.
+
+Pluto, or 134340, is in the centre and its satellite Charon, 134340 1, is just below it. The newly discovered satellites, now called 134340 II and 134340 III, are to the right
+Pluto has been stripped of its membership of the cosmic A-list and given a humble new tag: 134340.
+The enigmatic, icy world spotted in 1930 is know officially known as 134340 Pluto.
+It has been lumped among 136,562 asteroids and other small bodies by the Minor Planet Center, part of the International Astronomical Union (IAU). 
+Pluto's satellites, Charon, Nix and Hydra, have been numbered 134340 I, 134340 II and 134340 III respectively under the latest minor planet list.
+The IAU last month declared Pluto to be a 'dwarf planet' that should not belong among the hallowed ranks of Mercury, Earth, Venus, Mars, Jupiter, Saturn, Uranus and Neptune.
+The organisation is now drawing up a catalogue of dwarf planets whose initial members will include Pluto, the large asteroid Ceres and a distant object, 2003 UB313, unofficially named Xena.
+Until the IAU meeting, 2003 UB313 had laid claim to being the solar system's 10th planet.
+Rebel astronomers are circulating a petition, contesting the dwarf planet definition as unscientific and the decision on Pluto as undemocratic.
+They intend to hold a conference next year that, in their view, will overhaul the definition of a planet. 
+Pluto's status had long been contested by astronomers who say its tiny size, odd orbit and orbital plane preclude it from joining the other acknowledged planets.
+By the new IAU yardstick, a planet has "cleared the neighbourhood around its orbit". In other words, it is massive enough to wield a gravity that clears rocks and other debris on its orbital path.
+
+The report likens the rock art to the Palaeolithic art of Western Europe
+The largest collection of ancient rock art in the world, located in the rugged northwest of Australia, should be entirely protected from industry, says a new report.
+The report on the archaeology and rock art in the Dampier Archipelago was released this week by the National Trust of Australia (WA).
+It fuels ongoing debate about development in the area, which is being considered for National Heritage listing.
+Robin Chapple, of the National Trust, says there are around a million rock carvings on the archipelago.
+And he says 500,000 of these petroglyphs are estimated to be on the Burrup Peninsula, where Woodside Energy was recently granted permission from the Western Australian government to begin development of a natural gas project.
+"It's basically the largest collection of rock carvings in one location," says Chapple.
+The report says some of the oldest of the carvings, which are tens of thousands of years old, include those of archaic faces.
+And there are also depictions of animals that disappeared long before Europeans arrived on the continent.
+For example, there are carvings of thylacines, which have been extinct on the mainland for 3000 years. 
+Other evidence of prehistoric human activity on the archipelago includes food preparation sites, quarries, stone arrangements and terraces.
+"It's a bit like walking into the Mary Celeste," says Chapple. "You've got this whole feeling like you're actually in someone's living room."
+
+The last Neanderthals holed up in Gibraltar, a refuge on the balmy southern tip of Europe, until their lineage withered away, scientists say
+Neanderthals lived in southern Europe as recently as 28,000 years ago, had a varied diet and used sophisticated tools and weapons, scientists say.
+Homo neanderthalensis was thought to have survived in Europe until the arrival of modern humans about 30,000 years ago.
+But new findings by Professor Clive Finlayson of the Gibraltar Museum show the two groups may have coexisted in Europe for 4000 years or longer. 
+"We are showing quite clearly that they survived at the very least until 28,000 years ago and possibly as recently as 24,000 years. That is significantly later than previously thought," Finlayson says.
+With Europe in the grip of an Ice Age and with their smarter cousins, Homo sapiens, spreading across the continent, the last Neanderthals holed up in a refuge on the balmy southern tip of Europe until their lineage withered away, the study says.
+Neanderthals were predecessors of modern humans who inhabited Europe and parts of west and central Asia.
+Despite their image as club-carrying, hairy brutes, research suggests they were expert tool makers, used animal skins to keep warm and may have cared for each other.
+During a new excavation at Gorham's Cave, a rich source of prehistoric artefacts in Gibraltar, Finlayson found a campfire made by Neanderthals and remains of tools, flint weapons and animal fossils. 
+Remains included those of mammals, birds and shellfish, Finlayson says.
+Charcoal found at the site enabled the scientists to date it. They were also able to reconstruct the environment in which the late Neanderthals lived and found it included a variety of plants.
+"It indicates to us that in spite of the glaciations further up in Europe, this was a place where the climate was still sufficiently mild for populations of Neanderthals to survive quite late," adds Finlayson, whose findings are reported online by the journal Nature.
+"The last Neanderthals that occupied Gorham's Cave had access to a diverse community of plants and vertebrates on the sandy plains, open woodland and shrubland, wetlands, cliff and coastal environments surrounding the site," the study says. 
+"Such ecological diversity might have facilitated their long survival." 
+The scientists are excavating further in the cave where stone tools were discovered more than 50 years ago. They will also be looking for Neanderthal burial sites in the cave's deeper parts.
+Co-existing with humans
+How long Neanderthals and modern humans coexisted in the same geographical area is a subject of much debate, with some researchers suggesting it could have been as short as 2000 years. 
+"Here we are looking at 4000 years, if not more, and that is a long time" says Finlayson.
+"It sounds like very little, but if you transpose it into human generations today, 4000 years is from the time of Christ to the present and back," he adds. 
+What happened to Neanderthals then?
+As to the great whodunnit of palaeontology, the paper discounts the theory that these Neanderthals were annihilated by H. sapiens in the competition for food and territory.
+Evidence of stone-age technology at Malaga, about 100 kilometres east of Gibraltar, shows that anatomically modern man had ventured into the neighbourhood at the time when the Neanderthals lived in Gorham Cave. 
+This suggests that for several thousand years the region was a 'mosaic' of remnant Neanderthals and pioneering H. sapiens living in thinly-scattered communities.
+Neanderthal DNA in modern humans?
+Another theory to explain the disappearance of the Neanderthals is that they did not disappear, not genetically, at any rate. 
+Under this hypothesis, Neanderthals and H. sapiens co-mingled. Far from being a dead branch of the human tree, the Neanderthals may even have bequeathed some of the traits in the H. sapiens genome that we see today.
+The new paper does not address this controversial theory, but notes there is no evidence of "transitional" tools or activities at the cave. 
+This adds weight to the argument that the last Neanderthals had only limited contact with H. sapiens, so interbreeding was unlikely.
+The first evidence for the Neanderthals emerged in 1856, when workers at a lime quarry in the Neander Valley, western Germany, came across bones initially thought to be that of a bear.
+Since then, the remains of about 400 Neanderthals have been found, at sites ranging from southern England to continental Europe and the Middle East.
+
+These magnetic patches cause variations in the Sun's brightness. But research released today says these variations are not enough to cause climate change
+The Sun's energy output has barely varied over the past 1000 years, according to a study that weakens claims that climate change is due to natural sunspot cycles.
+An international team of researchers found that the Sun's brightness varies by only 0.07% over 11-year sunspot cycles, far too little to account for the rise in temperatures since the Industrial Revolution. 
+"Our results imply that over the past century climate change due to human influences must far outweigh the effects of changes in the Sun's brightness," says Australian born Dr Tom Wigley of the US National Center for Atmospheric Research. 
+Many scientists say that emissions of greenhouse gases, mainly from burning fossil fuels in power plants, factories and cars, are the main cause of a 0.6&deg;C rise in temperatures over the past century. 
+A smaller group of scientists says that the dominant cause of warming is a natural variation in the climate system, or a gradual rise in the Sun's energy output.
+"The solar contribution to warming over the past 30 years is negligible," the researchers write in the journal Nature, based on evidence from satellite observations since 1978.
+They also found little sign of solar warming or cooling when they checked telescope observations of sunspots against temperature records going back to the 17th century. 
+They then checked more ancient evidence of rare isotopes and temperatures trapped in sea sediments and Greenland and Antarctic ice and also found no dramatic shifts in solar energy output for at least the past millennium.  
+Sun not guilty, says study
+"This basically rules out the Sun as the cause of global warming," says Dr Henk Spruit, a co-author of the report from the Max Planck Institute for Astrophysics in Germany. 
+Spruit says a Little Ice Age around the 17th century, when London's Thames River froze, seemed limited mainly to western Europe and so was not a planet-wide cooling that might have implied a dimmer Sun. 
+And global Ice Ages, like the last one that ended about 10,000 years ago, seem linked to cyclical shifts in the Earth's orbit around the Sun rather than to changes in solar output.
+"Overall, we can find no evidence for solar luminosity variations of sufficient amplitude to drive significant climate variations on centennial, millennial or even million-year time scales," the report says. 
+Solar activity is now around a low on the 11-year cycle after a 2000 peak, when bright spots called faculae emit more heat and outweigh the heat-plugging effect of dark sunspots.
+Both faculae and dark sunspots are most common at the peaks. 
+Still, the report also says there could be other, more subtle solar effects on the climate, such as from cosmic rays or ultraviolet radiation. It says they would be hard to detect.
+
+The double-pulsar system put Einstein's theory of general relativity through its paces, with what's believed to be the most stringent test yet
+Pulses of radiation emitted from a pair of distant stars have confirmed that Einstein's theory of general relativity is at least 99.95% right, scientists say.
+An international research team including scientists working at Australia's Parkes telescope measured the radiation from a 'double pulsar' system 2000 light-years away to put the theory through its paces.
+According to results published online today in the journal Science, the 91-year-old theory came through with top marks.
+"General relativity has passed all our tests," says co-author Dr George Hobbs from the Australia Telescope National Facility.
+The double pulsar system, called PSR J0737-3039A and B, consists of two highly compact neutron stars, each of which weighs more than our own Sun but measures only about 20 kilometres across.
+The two stars whirl around each other at a million kilometres an hour, emitting lighthouse-like beams of radio waves.
+Researchers used three of the world's largest radio telescopes, the UK's Lovell Telescope at Jodrell Bank, the Parkes radio telescope and the Robert C Byrd Green Bank Telescope in West Virginia in the US, to observe those beams over a period of three years.
+Their measurements offered a number of ways to test the accuracy of the theory of general relativity.
+The most precise is called the Shapiro delay, and concerns Einstein's prediction that massive objects warp space-time.
+"Einstein says that the whole concept of space and time are connected and that gravitational fields warp both of them," explains Hobbs.
+This means that when one pulsar passes behind the other, its signal travels through the warped space-time created by the one in the foreground.
+Using Einstein's theory, the researchers calculated that this warping would add a 90 microsecond delay to the arrival of the signal on Earth, which is just what their measurements found.
+"The first thing to say is that the prediction and the measurement agree," Hobbs says.
+"But it isn't possible for our measurement to be 100% precise."
+What the scientists can say for certain is that Einstein's theory is accurate to at least within 0.05%.
+"General relativity is used in astronomy all the time, on the assumption that it is correct," says Hobbs.
+"This is the most stringent test ever made of it in the presence of a very strong gravitational field."
+
+Nanotechnology involves manipulating matter at the atomic or molecular level
+A nine-point plan for the responsible development of nanotechnology in Australia has been recommended in a new report. But environmental and worker safety groups are still not happy.
+The industry minister Ian Macfarlane this week released the report, which he will consider when establishing a national nanotechnology strategy.
+It recommends the establishment of a dedicated office within a federal department that will be responsible for the nanotechnology strategy, although it does not recommend which portfolio this should fall under.
+The report states that there is no case for establishing new, nanotechnology-specific regulations to protect human health and the environment, but suggests existing regulations may need adjusting.
+The Options for a National Nanotechnology Strategy report also recommends further research into the health, safety and environmental implications of nanotechnology.
+And it recommends that any proposed changes to regulatory frameworks should "not add unnecessary regulatory burden to industry".
+Nanoparticle risk
+Australian Council of Trade Unions occupational health and safety officer, Steve Mullins, supports the establishment of a specific office to oversee nanotechnology.
+But he criticises the report's failure to recommend the establishment of new regulations specific to nanotechnology.
+"It seems like business has the green light to use nanotechnology but they've got a red light on health and safety regulation," he says.
+The unions are particularly concerned about the exposure of workers to nanoparticles and believe precautionary measures should be taken to ensure this is minimised.
+"By all means, continue research," says Mullins. "But we've got enough evidence to suggest nanoparticles can have a toxic effect on the body."
+Georgia Miller of the Friends of the Earth's nanotechnology project also criticises the report.
+She says it fails to require safety testing of nanoparticles before they are commercialised, as recommended by the UK's Royal Society in 2004.
+She says there should be a moratorium on r&d and manufacture on nanotechnology until safety issues are resolved.
+
+The celestial body now known as Eris with her moon Dysnomia
+'Xena', the lonely rock at the edge of the solar system that caused Pluto's downfall has now been officially named Eris after the Greek goddess of strife.
+"Eris caused strife and discord by causing quarrels among people and that's what this one has done too," says Assistant Professor Mike Brown, the California Institute of Technology researcher who discovered the object. 
+Brown's discovery, larger and further from the Sun than Pluto, set off a heated debate about what should be considered a planet. 
+The 2500 members of the International Astronomical Union decided last month to downgrade Pluto to a 'dwarf planet', leaving only eight full planets in the solar system.
+Many scientists have not accepted the change. 
+Eris, pronounced EE-ris, is also considered a dwarf planet. The most distant known solar system object from the Sun, it takes 557 years to complete an orbit.
+Unlike Pluto, its orbit does not cross paths with Neptune, the most distant full-sized planet. 
+The body was dubbed 2003 UB313 after it was discovered. Brown nicknamed it Xena, after the television warrior princess. But he says he didn't consider that to be an appropriate formal name for a celestial body.
+"Then the next one would be Spock or something, and that wouldn't be quite so dignified," Brown says.
+The astronomers' union accepted Eris this week. The group also accepted Brown's proposed name for Eris's moon Dysnomia. 
+Dysnomia is Eris's daughter in Greek mythology, and the word means lawlessness in Greek.
+"It sounds like a disease. But in any case we all liked it," says Dr Ted Bowell, an astronomer at Lowell Observatory in Arizona who heads the division of the astronomers' union that deals with planets.
+Brown says he plans to study Eris and Dysnomia further to figure out the dwarf planet's mass and density.
+Greek mythology
+In Greek mythology, Eris started the Trojan war after she was excluded from a wedding on Mount Olympus, home of the gods.
+To get revenge, she tossed an apple inscribed "to the most beautiful one" into the party, causing a squabble among the goddesses. 
+Paris, the prince of Troy, was forced to settle the dispute by picking one goddess as most beautiful, earning the spite of the others and the ultimate defeat of his city in the Trojan war.
+
+Chlamydia infects the back of the crocodiles' throats, causing an inflammation that blocks the airway
+Chlamydia is suffocating thousands of young, farmed crocodiles in Australia's north, say experts.
+Dr Ian Jerrett, senior veterinary pathologist at the Northern Territory government's Berrimah Veterinary Laboratories, says the disease is killing saltwater crocodiles (Crocodilus porosus).
+"I think it's the first very serious disease of crocodiles that we've recognised since farming started," Jerrett says.
+The disease affects young crocodiles, between three and five months old, causing an eye discharge and severe inflammation at the back of the throat that stops them from breathing.
+"These crocodiles are dying from obstruction of the larynx," says Jerrett. "They can't breathe because of the amount of damage in the back of the throat."
+The disease has been found so far on four of the five large crocodile farms in the Northern Territory, says Jerrett, with two farms seriously affected.
+"One farm, over a period of two months, lost about 2000 of their young crocodiles, which was nearly the whole crop for that year," he says. 
+"And another farm lost over 1000 which was about 30% of their crop for the year."
+At first a pox virus was suspected but virtually all the samples taken from the animals have since shown the culprit is chlamydia, unusual bacteria that need host cells to multiply. 
+The researchers will use DNA analysis to compare the strain to those that infect other animals such as wild birds. But they suspect it will be a strain specific to crocodiles.
+The strain involved is related to the strains that infect columnar epithelial cells in the genitals and eyes of koalas and humans, says Jerrett.
+
+Mosquitoes carrying the malarial parasite are responsible for killing about a million people a year
+DDT, the long-banned insecticide blamed for killing birds and other wildlife, is now approved for use indoors to fight malaria, says the World Health Organization.
+"One of the best tools we have against malaria is indoor residual house spraying," says Dr Arata Kochi, director of the WHO malaria department.
+"Of the dozen pesticides WHO has approved as safe for house spraying, the most effective is DDT."
+For about US$5 per house, indoor spraying with DDT is a cost-effective response to malaria, says the WHO.
+Malaria kills about a million people annually, most of them children under five.
+In parts of Africa and Asia where malaria-carrying mosquitoes spread the disease, 85% of home dwellers approached by health workers allow their houses to be sprayed, say global health officials. 
+DDT came into common use in the 1930s as an agricultural insecticide. It became notorious after biologist and ecologist Rachel Carson's 1962 book Silent Spring exposed how DDT entered the food chain, killing wildlife and threatening humans.
+In 1969, the US National Cancer Institute announced findings that DDT could cause cancer, and a US federal ban was imposed in 1972.
+Richard Tren, director of the group Africa Fighting Malaria, stresses the difference between agricultural DDT sprayed outdoors and the residual spraying means to act like a giant mosquito net over individual houses.
+"The environmental impact associated with spraying insecticides, whether it's DDT or other insecticides, indoors is minimal, it's negligible ... This is as unrelated to Silent Spring as anything," Tren says. "The science is very clear that there are no harmful human effects."
+Tren says environmental groups in Africa support its use. 
+In Washington, the director of the Sierra Club's environmental quality program gives muted backing to the plan. 
+"Reluctantly, we do support it," says the group's Ed Hopkins. "Malaria kills millions of people and when there are no other alternatives to indoor use of DDT, and where that use will be well-monitored and controlled, we support it." 
+Hopkins stresses the need for safer alternatives to DDT, "because DDT is not a silver bullet to solve this problem".
+
+Damaged telomeres have prevented this yeast cell from dividing. Instead, it has continuously replicated its DNA to prepare for division. This has resulted in numerous copies of DNA, seen here as multiple bright spots
+An Australian-born scientist is among three researchers who have been awarded a prestigious Lasker award for the discovery of telomerase, an enzyme key to ageing and cancer.
+Professor Elizabeth Blackburn, of the University of California, San Francisco, has been awarded the Lasker Award for Basic Medical Research.
+She shares the award with Professor Carol Greider of Johns Hopkins University School of Medicine in Baltimore and Professor Jack Szostak of Harvard Medical School and the Howard Hughes Medical Institute. 
+The three predicted and discovered telomerase, an enzyme that synthesises and protects the telomeres at the ends of chromosomes.
+Their discoveries laid the groundwork for studies connecting telomerase and telomeres to human cancer and age-related conditions. 
+"Today, telomerase research is one of the hottest fields of biomedical science," says Dr Joseph Goldstein, who won a Lasker and a Nobel prize for helping to discover cholesterol and who chairs the Lasker jury. 
+Blackburn, a stem cell scientist, was dismissed from the US President's Council on Bioethics in 2005 amid controversy over her support of embryonic stem cell research, which President George W Bush opposes.
+The awards, considered the US equivalents of the Nobel prizes for medical research, carry an award of US$100,000.
+The Lasker Award for Clinical Medical Research went to Aaron Beck, emeritus professor of the University of Pennsylvania School of Medicine, for developing cognitive therapy. 
+Cognitive therapy, a type of talk therapy, can treat mental conditions such as depression, suicidal behaviour, and eating disorders.
+The Lasker Award for Special Achievement in Medical Science went to Joseph Gall, of the Carnegie Institution's Department of Embryology at Baltimore, for his work as a founder of modern cell biology and an early champion of women in science. 
+Gall invented a technique called in situ hybridisation, now routinely used by scientists.
+"This method can pinpoint a single gene among the 30,000 present in the genomes of humans and animals," Goldstein says. 
+The Lasker Awards, first presented in 1946, are administered by the Lasker Foundation.
+
+The ability to download music has made it possible for athletes to better exploit the power of music while training and competing
+Technology like the mp3 player is revolutionising sports psychology, according to an expert who says these devices are allowing athletes to harness the psychological benefits of music as never before.
+Professor Peter Terry of the University of Southern Queensland says technology like running shoes that increase the beat of music in time with a runner's pace and even implantable micro-mp3 players may one day give athletes the winning edge.
+"It's certainly going to add a new level to [athletic] potential," says Terry, who has been to seven Olympic Games as a sports psychologist and published widely on the power of music in enhancing athletic performance.
+But he says the technology could create a whole new conundrum for sports authorities by making them redefine whether the use of performance enhancing music is cheating.
+Terry will talk about the latest research into the psychological effects of music in sport at a joint conference of the Australian Psychological Society and the New Zealand Psychological Society in Auckland next week.
+Terry says the benefits of music on exercise have been known since the days that galley slaves were forced to row to the rhythm of drum beats.
+But it's only in the past decade that this has been scientifically demonstrated.
+Music boosts performance in a number of ways, he says.
+"If you synchronise whatever activity you're engaging in to the tempo of music there's a very clearly energic effect," he says.
+"In other words, if you play music with a fast tempo, people work harder."
+Music also acts as a mood enhancer, which can put athletes in a "winning" mood, he says.
+Music like Eye of the Tiger and the theme from Rocky are classics.
+Whitney Houston's One Moment in Time was a particular favourite with certain members of the Australian team during the Sydney Olympics who saw it as reflecting their personal goal to 'seize their moment'.
+"It's a bit cheesy but a number of people really bought into it and the lyrics supported what they were about," he says.
+But music choices can sometimes be counterintuitive, he says, citing a super heavyweight boxer who liked to listen to classical Japanese music before getting into the ring.
+Terry says a computer company has already entered a deal with a sportswear manufacturer to produce an armband you can slip your mp3 player into.
+Also in the pipeline are shoes with sensors that pick up how fast you're going and coordinate the beat of the music to ensure you maintain the pace.
+He also says being able to download music has made it easier for athletes to come up with music that's highly personalised to their individual training and competing program.
+In 1998 Haile Gebreselasie set an indoor world record for the 2000 metres by synchronising his stride rate to the song Scatman.
+"At the moment the attitude towards that is that it's almost cheating, and that's because that synchronous effect is so well understood" Terry says. 
+The question of cheating may become even more fraught with the prospect of tiny mp3 players that can be worn under the skin.
+"People are already having implants for contraception, why not for performance?" Terry says.
+"I think there's a whole new world possible as microtechnology develops."
+
+Australian diggers in the trenches of Gallipoli in 1915
+Australia is to be part of a major three-nation archaeological survey of the Gallipoli battlefield, researchers say.
+Associate Professor Chris Mackie from the University of Melbourne says the survey will combine conventional mapping with electromagnetic surveying to produce the most comprehensive historical and archaeological study ever conducted there.
+"Most of the attention in the post-war period has been on the cemeteries," he says about studies of Turkey's Gallipoli Peninsula.
+"One of the things we'll be spending a great deal of time on is the mapping of the trenches to see how they cohere with surviving maps of the trenches and exploring what lies beneath."
+Mackie says there's a "distinct possibility" that a wealth of material dating back to the days of antiquity lies buried beneath the battlefield, perhaps the most historically significant military site in Australia's history.
+"Records from sappers dating back to 1915 mention ancient pots, ancient remains and so forth, so there could be material there," he says.
+"Because we'll be using electromagnetics you're coming up with all sorts of possibilities, everything from material left behind in the battle itself to much older stuff."
+The survey, which will be conducted by researchers from Australia, New Zealand and Turkey, will also aim to identify any significant trenches, command posts, outposts and key battle areas, says a spokesperson for the federal department of veterans' affairs.
+"Basically [we hope to produce] a catalogue of the ones we know of and also see if there's any ones we weren't aware of," the spokesperson says.
+"[The researchers] hope to get together a comprehensive record of sites, gauge their condition and also recommend any ways that we can possibly protect them and enhance them."
+Will the site be dug up?
+Mackie says because of the historical and cultural sensitivity of the site "there's no intention to embark on any excavation".
+The veterans' affairs spokesperson says: "It's going to be fairly comprehensive archaeological historical research."
+Mackie says many people are unaware of the historical importance of the region, which includes the nearby site of the ancient battle of Troy.
+The project was scheduled to have started earlier this year but has been delayed by diplomatic and heritage considerations, the veterans' affairs spokesperson says.
+Remains of diggers found in Belgium
+Confirmation of the Gallipoli survey comes as the federal government announces that the remains of what are believed to be five Australian World War I soldiers have been found on the Western Front in Belgium during excavations for a gas line at Frenzenbergstraat in Zonnebeke.
+The discovery has been reported to the Commonwealth War Graves Commission and the Office of Australian War Graves is awaiting a full report, says veterans' affairs minister Bruce Billson.
+He says the government will attempt to identify the remains once a report is at hand.
+
+The Solar-B mission will measure the movement of magnetic fields and how the Sun's atmosphere responds to them
+Scientists will launch a new space mission later this week to study the most violent explosions in the solar system.
+By monitoring the Sun's magnetic field the Solar-B mission, a UK, US and Japanese collaboration, hopes to learn more about solar flares.
+These bursts of energy are equivalent to tens of millions of hydrogen bombs exploding in a matter of minutes, the scientists say.
+"What we want to do is explore the most energetic explosions in the solar system so we can actually predict when they will occur and why they happen," Professor Louise Harra, of University College London's Mullard Space Science Laboratory, told a recent conference. 
+Instruments on the spacecraft will measure the movement of magnetic fields and how the Sun's atmosphere responds to them. 
+The mission will focus on solar flares' trigger phase. 
+Solar flares occur when energy stored in twisted magnetic fields is suddenly released. And the largest flares occur where there are the strongest magnetic fields.
+Flares are usually associated with sunspots, dark cool areas caused by intense magnetic fields breaking through the Sun's surface.
+They pose a danger to astronauts and spacecraft and can cause havoc with satellite links, power grids and mobile phone networks on Earth. 
+"Solar flares are fast and furious. They can cause communication blackouts on Earth within 30 minutes of a flare erupting on the Sun's surface," says Harra. 
+"In terms of heat it is 10,000 times hotter than a volcanic eruption," she added in a briefing at the recent British Association for the Advancement of Science festival.
+The heat generated by a solar flare, first observed in England in 1859, causes atmospheric gases to start to move at enormous speeds, more than 10 times faster than the speed of Concorde.
+Solar-B is set to launch on Saturday morning Australia time (late Friday UTC) from the Uchinoura Space Centre in southern Japan.
+During its three-year mission it will orbit at an altitude of 600 kilometres to get a continuous view of the Sun.
+Harra says a better understanding of solar flares could provide information about how magnetic fields release huge amounts of energy and whether life can exist somewhere else.
+
+The king protea, one of the largest of all South African proteas, is related to proteas throughout the southern hemisphere
+The protea family spread through the southern hemisphere by riding on fragments of the ancient supercontinent Gondwana, according to a scientist who says his research deals a blow to intelligent design.
+Australia's Dr Peter Weston, the principle research scientist at the National Herbarium of New South Wales, has been researching the biogeography of the family Proteaceae.
+The family is common in Australia and includes waratahs, grevilleas, proteas, banksias and even macadamia trees.
+Varieties are also found in South Africa, Southeast Asia, New Guinea, New Caledonia, New Zealand and Madagascar.
+"Most of the areas in which they grow are pieces of ... Gondwana that started fragmenting hundreds of millions of years ago," Weston says.
+"After [the idea of] continental drift became accepted in the late 1960s and early 1970s it also became accepted that the Proteaceae became primarily distributed as a result of continental drift."
+Weston is looking at how species spread to different parts of the world and evolveed, and is using molecular dating, to support this hypothesis.
+He will discuss his latest research in an Australian Academy of Science lecture in Canberra next month.
+For example, he says his analysis shows that the ancestors of the Sydney waratah come from northern Queensland, New Guinea and as far as Peru, Ecuador, Chile and Argentina.
+The research supports Darwin's theory of evolution as opposed to the view that everything was simultaneously created by an intelligent designer, Weston says.
+"Life on Earth has evolved together so we've got a narrative of the history of the Earth and we've got a comparable story about the history of these plants," he says.
+"If these plants hadn't evolved why would you expect this degree of agreement?"
+But molecular dating by Weston and colleagues at Rhodes University in South Africa has come up with some surprises when compared with geological data on continental drift.
+For example, some groups of protea found both in Australia and Africa have been dated at about 40 million years old, millions of years after Gondwana split.
+This makes them too young to have arrived by continental drift because according to geological records the last time Africa was connected to the rest of Gondwana was more than 100 million years ago.
+So, how did they arrive in Australia?
+Weston says some protea seeds are light and aerodynamic, making it likely they were distributed on the wind.
+The strange case of the macadamia tree
+But more puzzling is the strange case of the macadamia.
+Molecular dating shows the variety found in Africa's Western Cape split from the Australian variety about 50 million years, or 50 million years after the accepted time of continental fragmentation.
+Because macadamia nuts are heavy and rock-like, it's unlikely they were carried by the wind or even floated across the ocean, Weston says.
+The split also predates humans, ruling out that they were distributed by hand.
+"I find it hard to explain," he admits.
+Weston says while Darwin believed biogeography was a crucial test of evolution, the great naturalist didn't support continental instability.
+But his friend, the British botanist Joseph Hooker, suggested as early as 1853 that Proteaceae in southern continents must have achieved their distribution through climatic and geographic conditions.
+
+Genes influence how you learn to read and spell
+The genes involved in learning to sound out words are different from the ones involved in learning to recognise words by sight, according to an Australian study.
+The finding, published online in the journal Reading and Writing, adds fuel to the debate about the best way of teaching children to read.
+There are two particular skills that children need to learn if they are going to be good readers.
+The first is the sounding out process, known as phonics.
+The other skill is being able to recognise familiar words pretty much by sight. This helps when they read words such as 'yacht' that don't follow the phonics rule.
+Researchers including Associate Professor Anne Castles, from the University of Melbourne, tested different genetic models for reading and spelling in 691 sets of identical and non-identical twins to determine to what extent these skills are genetically based. 
+Twins are ideal for this type of research because identical twins are more similar genetically than non-identical twins.
+So if a skill has a genetic basis, identical twins tend to be more similar to each other than non-identical twins.
+The researchers found that both reading and spelling skills do have a genetic basis, although a child's environment is also important.
+"Not all of that skill is something you are born with, but there is a genetic component," Castles says.
+The particularly novel thing about this study is that different sets of genes seem to be involved to some degree for those different processes.
+"So the genes for learning to sound words out are different from the ones that are involved in learning to recognise words by sight. But certainly many genes were shared in common as well."
+A second finding is that reading and spelling have a common genetic basis, meaning that if children are having difficulty spelling they will also be likely to struggle with learning to read. 
+Castles says the research has implications for future research into reading and spelling. 
+"The existence of different reading sub-skills, with different genetic bases, needs to be reflected in our theories of reading and its acquisition," she says.
+
+The next time you go to a sports game at a large open-air stadium, listen to the weather forecast, say meteorologists
+Large open-air stadiums could be severe weather death traps, says a US meteorologist in a new study on lightning storms and sports stadiums.
+Few people have been struck by lightning in stadiums and no US stadium has suffered a direct tornado hit during a game.
+But the University of Colorado scientist says stadiums are not immune to these dangers and stadium managers can do something to prevent a calamity.
+The most infamous case of a poorly handled lightning storm at a big stadium was the 1998 Virginia Tech game at RKF Stadium in Washington DC, reports Joel Gratz in the September issue of the Bulletin of the American Meteorological Society.
+Lightning struck and killed one woman and caused numerous injuries when 50,000 people panicked and raced chaotically to escape the stadium through narrow tunnels. 
+The stadium's jammed tunnels left many people in the open without protection. 
+During the next 10 minutes there were 16 more lightning strikes within a mile of the stadium, says Gratz.
+What went wrong? Stadium managers had no plan, police and ushers were unprepared to help people find cover, the stadium speaker system was inadequate and there was no lightning evacuation plan, says Gratz.
+Ironically, the reason there are no lightning plans is simple: the odds are miniscule that lightning will strike in a stadium just when a game is under way, Gratz says.
+"Statistically it may not make a lot of sense to look into it," says Gratz. But then again, he points out, odds are also very low of a terrorist attacks at any given stadium, yet there are plans in place for that.
+"Lightning is also one of those low-risk, but high-impact events."
+You can't just activate your terrorist plan when a lightning storm approaches and expect it to help, Gratz explains. 
+"Unlike a terrorist threat, moving people into the [carpark] or open field during an electrical storm will probably hurt people," he says.
+What's needed are evacuation plans that use the most lightning-protected places inside a stadium, nearby buildings, as well as better monitoring of the approaching weather by stadium officials, he says.
+Spectators themselves can prevent trouble too by paying better attention to severe weather warnings and acting on them, says meteorologist Professor William Gallus of Iowa State University.
+Gallus got a first-hand look at how tricky severe weather warnings and stadiums can be when a tornado threatened the Jack Trice Stadium in Ames, Iowa last November.
+"When this tornado touched down it was 15 miles [24 kilometres] away, it was live on TV," says Gallus.
+"Tailgaters [in the stadium carpark] were watching it" on portable televisions, he says.
+Yet there was little comprehension among spectators or stadium officials that at 80 kilometres per hour, the tornado could potentially reach the stadium in just minutes.
+"This event could have been such a tragedy," says Gallus. 
+Fortunately, the tornado did not hit the stadium this time.
+"People need to realise they need to take personal responsibility for their safety," he says.
+There is, indeed, a certain tendency for spectators to put on blinkers, Gratz says.
+"When you go into a stadium as a spectator people have weather information on PDAs and cell phones, but no one is really going to notice with the bright lights and game that there is an electrical storm 15 miles away."
+Gratz admits he has fallen prey to this blindness. He was at a game at Denver's Invesco Stadium when his father called his mobile phone and asked him why, if he was such a knowledgeable weather person, was he sitting out in the open at a stadium along with 50,000 other people when a nasty electrical storm was closing in?
+"It was fatherly wisdom," recalls Gratz. And it's exactly what got him interested in whether stadium management was really prepared.
+
+The fossil child has been named Selam, which means peace in Ethiopia's official Amharic language
+A 3.3 million-year-old skeleton of the earliest child ever found shows the ancient ancestor of modern humans walked upright but may also have climbed trees, scientists say. 
+They found the well-preserved remains of a three-year-old girl of the species Australopithecus afarensis, which includes the fossil skeleton known as Lucy, in the Dikika area of Ethiopia.
+"It represents the earliest and most complete partial skeleton of a child ever found in the history of palaeoanthropology," says Dr Zeresenay Alemseged, of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. 
+The skull, torso and upper and lower limbs, including the hand, show both human and ape-like features, the scientists report in the latest issue of the journal Nature.
+The state of the ancient bones, found 400 kilometres northeast of the capital Addis Ababa, suggest she was buried in a flood, which may also have caused her death. 
+The remains provide the first evidence of what babies of early human ancestors looked like. The nearly complete skeleton will also provide information about the child's height and structure. 
+"This child will help us understand a lot about the species to which it belongs," says Alemseged, leader of the international team of scientists.
+"The lower part of the body, which includes the foot, the shin bone and the thigh bone clearly shows us that this species was an upright walking creature," he says. 
+But some of the features from the upper part of the body, including the shoulder blade and arms are more ape-like.
+The fingers are long and curved which suggest she might have been able to swing through trees. 
+"The finding is the most complete hominid skeleton ever found in the world," says Alemseged.
+He says the fossil was older than the 3.2-million-year-old remains of Lucy discovered in 1974, described by scientists as one of the world's greatest archaeological finds.
+"The new bones belong to a three-year-old girl who lived 3.3 million years ago, 150,000 years before Lucy," Alemseged says. 
+The fossil has been named Selam, which means peace in Ethiopia's official Amharic language.
+Dr Simon Underdown of Oxford Brookes University in England describes it as a massively exciting discovery of a juvenile Lucy.
+"This tremendous fossil will make us challenge many of the ideas we have about how and why we came to walk on two feet," he says. 
+An analysis of the sediment in which the remains were found enabled researchers to build a picture of the type of environment in which the child lived. 
+It was a lush area with flowing water, forests and grassland, which was also affected by volcanic eruptions. The range of habitats was suitable for hippos, crocodiles and relatives of the wildebeest.
+"We can see from the sediment that the region was very much characterised by a mosaic of environment that ranged from forests and woodlands near the rivers, to seasonally flooded grasslands to a flood plain that would have supported more open vegetation," says Dr Jonathan Wynn of the University of South Florida, who dated the sediments surrounding the remains.
+Australopithecus
+Once thought by some to be our ancestor, A. afarensis is now widely considered to be a failed branch of the human tree, for many experts suspect the hominid was anatomically far closer to apes than humans. 
+Its brain, adjusted to its body size, was not much larger than that of a chimpanzee and although it no longer had the large canines that distinguished apes from hominids, it had relatively large chewing teeth that were still primitive. 
+The other comparably complete infant hominid skeleton in the fossil record is that of a Neanderthal child who lived less than 100,000 years ago.
+
+Could you be churning out your own car from a desktop factory in 15 years?
+Within 15 years, desktop nanofactories could pump out anything from a new car to a novel nanoweapon, says a technology commentator.
+And he warns that society needs to start preparing for this brave new world.
+Mike Treder from the Center for Responsible Nanotechnology (CRN) in New York says advanced nanotechnology, like these nanofactories, could help solve world poverty but it could also wreak economic and social chaos.
+"It's the biggest challenge we've ever faced as a species," says Treder, who has been addressing scientists in Australia this week.
+CRN is a non-profit organisation advised among others by the so-called father of nanotechnology, Dr Eric Drexler.
+The organisation says it aims to raise awareness about the benefits and dangers of molecular manufacturing, the precise assembly of products atom-by-atom.
+While molecular manufacturing is not yet a reality, Treder says researchers are already working on building molecular-scale machines that could eventually move atoms around to make products. 
+And he says that in less than 15 years, nanoscale factories could be making consumer products from cups and chairs to cars and house bricks. 
+Raw materials like carbon would be pumped into the nanofactory, where atoms would be rearranged to make products according to programs downloaded from the internet, says Treder.
+Warnings
+Treder says such desktop nanofactories could help reduce poverty and starvation in developing nations, and provide tremendous medical benefits. But society needs to guard against its potential risks.
+In particular, he says CRN is concerned that these desktop nanofactories would lead to a nano "arms race" in which hard-to-detect nanoweapons could be designed, manufactured and tested much quicker than they are today.
+"Imagine a suitcase filled with billions of toxin-carrying flying robots that could be released anywhere to target a population," he says.
+"You could make a suitcase full of these things overnight for a few dollars."
+The mass production of consumer goods by private desktop factories could also trigger social chaos due to economic disruption, says Treder.
+"If I can make my own car at home for a couple of hundred dollars with a design downloaded from the internet that means I'm not a customer of the auto dealer down the road."
+Waste from such easy manufacturing, or nanolitter, is another issue that needs to be thought about, he says. As is the prospect of nanospam.
+
+Flying foxes reportedly flew away from the storm, probably in response to rapidly dropping air pressure
+Cyclone Larry, which hit Australia's northeast in March, has scattered 10,000 flying foxes far and wide, says a zoologist.
+And CSIRO's Dr Louise Shilton needs to find this local species of crow-sized, fruit-eating bat quickly.
+The event is both good and bad for her ongoing project to monitor the usually poorly distributed animals. 
+It's bad news because it's rather difficult to study animals you can't find. 
+"We need to be providing the best possible population data and we can't monitor them without knowing where they roost," says Shilton.
+Among her questions are what they are eating and where they have chosen to roost.
+The good news is that when she finds them, she'll probably be able to learn what these animals regard as good habitat, a matter of debate at the moment, she says.
+Do they really depend solely on undisturbed forest or do they like urban areas where fruit trees are irrigated and predators are few? 
+It's the sort of thing people who love, and those who loathe, flying foxes want to know. 
+"There's this kind of love-hate relationship with fruit bats in Australia," says Shilton. 
+Some people adore them and point to evidence that flying foxes play a critical role in pollinating and spreading the seeds of native plants. Others are less enthusiastic.
+"They do come into contact with fruit growers," says Shilton. "But they also come into conflict with people in urban environments."
+That's because the bats congregate in large noisy crowds and produce foul-smelling guano.
+The animosity was bad enough that it was once common for people to shoot flying foxes. Now, however, the local northern Queensland species is protected and a permit is required to kill them.
+"This particular species is the one with the smallest distribution and it is believed to have the smallest population," Shilton says.
+Scattered or killed?
+Shilton is pretty certain the bats were scattered rather than killed by the cyclone, because she visited known roosting sites and found few dead animals, "just a handful compared to the 10,000 that had been around before the storm". 
+And some people reported seeing the bats hurrying away en masse before the storm arrived, probably a natural response to quickly dropping air pressure. 
+"I would agree that Queensland probably does offer more places for the flying foxes to escape the storm," says Dr Kim McConkey, a wildlife researcher who studied the effects of another cyclone on another species of flying foxes in Tonga.
+"We recorded an 80% decline in flying fox abundance in Tonga after the cyclone, and this was almost certainly due to mortality, either directly during the storm or afterwards due to a lack of food" and human hunting, she adds. 
+McConkey's colleagues also reported seeing bat carcasses in the lagoon after the island cyclone, she says. 
+Out in daylight
+To find out where the Queensland bats are, Shilton has asked the public to call her with information. Already, she says, there are sightings of flying foxes heading out for food in daylight, an unusual behaviour for the nocturnal animal. 
+That information alone suggests some bats are finding food scarce and working harder to get a meal.
+Meanwhile, says Shilton, anyone cheering at the flying foxes' disappearance shouldn't assume they have disappeared for good.
+"I've personally got no doubt that once the native trees come into season the bats will come back," Shilton says.
+
+Driveways, roads and patios make up 60% of impermeable urban surfaces. So why not harvest that water rather than let it run away?
+Carparks, patios and other paved areas could one day collect rainwater, purify it then channel it to underground tanks for reuse, say researchers.
+Special porous pavers made of concrete containing specific additives would purify the polluted run-off, says Professor Simon Beecham, a civil engineer from the University of South Australia.
+The water could then be captured in large underground tanks and be used for irrigation, cleaning and flushing the toilet, he says.
+"We're trying to harvest a resource that we've not been able to tap into before," says Beecham.
+Roads, driveways, pathways and the like make up 60% of impervious urban surfaces. And run-off from them causes flooding and pollutes our waterways.
+Until now harvesting rainwater from them has proved more difficult than from roofs, says Beecham.
+His team is developing a system in which porous concrete pavers allows run-off to seep into underground tanks made of galvanised metal or a flexible plastic lining filled with gravel.
+A special bonding material ensures the porous pavers are strong enough to withstand the heavy weight of cars and trucks.
+And additives mixed into the pavers, or into the sand and gravel bedding material beneath them, enables the system to trap pollutants.
+A paver injected with ferrous hydroxide, for example, traps toxic and persistent heavy metals like lead, zinc and cadmium that come from sources such as car tyres, brake-linings and exhaust.
+A layer of microbes on fabric beneath the pavers can trap and degrade hydrocarbons such as oil.
+And a layer of granulated activated carbon traps dissolved organic matter from leaf litter that is responsible for algal blooms in rivers, says Beecham.
+He says the pollutants can accumulate in the pavers over 25 to 30 years, allowing usable water to be caught and pumped above ground for reuse.
+He says the pavers could also allow trees, which themselves soak up and recycle water, to grow more freely because their roots have access to more water and air.
+Problem tree roots could be avoided by using a special concrete device that directs the roots away from the pavers, he says.
+And the pavers could be seeded with low maintenance native vegetation including sedges.
+Beecham says one of his PhD students Baden Myers is about to construct a full-scale prototype of the complete water harvesting and reuse system, which he predicts will cost 10 to 30% more than conventional paving.
+Part of the research has been submitted to Water Management, a journal of the UK's Institution of Civil Engineers.
+The South Australian government water authority SA Water is a major source of finance for the research.
+
+People who prefer old technology to new may form a new cultural group, just as they have done in history
+An underclass of internet 'refuseniks' may be breeding and planning terrorist acts in coming years to protest against technology, according to a survey.
+The poll by the Pew Internet and  American Life Project, an independent think tank, asked people what they thought of the effect of the internet on social, political and economic life in the year 2020.
+A total of 742 technology thinkers and stakeholders took part in the online survey.
+And a majority (58%) agreed with predictions that refuseniks will emerge as a cultural group characterised by their choice to live off the network and that some will resort to terror acts in protest against technology. 
+A total of 35% of respondents disagreed with that scenario and 7% had no opinion.
+"Constant change will spook some into trying to slow everyone down through horrific and catastrophic terrorist attacks against the information infrastructure and all who rely upon it," says Sean Mead, of Interbrand Analytics, who took part in the survey.
+Another respondent, Ed Lyell, an expert on the internet and education, says today's 'ecoterrorists' are the harbingers of this likely trend. 
+"Every age has a small percentage that cling to an overrated past of low technology, low energy lifestyle," he writes.
+"Led by people who only know the idealised past, not the reality of often painful past life styles, these Luddites will use violence to seek to stop even very positive progress."
+But some respondents warn against quickly applying labels to those who question the advance of technology.
+"We need some strong dissenting voices about the impact of this technology in our lives," writes Denzil Meyers of Widgetwonder.
+"So far, it's been mostly the promise of a cure-all, just like the past Industrial Revolution." 
+The survey, which was conducted with North Carolina's Elon University, also found that a majority of internet leaders, activists and analysts questioned agree with predictions that by 2020:
+&#149; A global, low-cost network will be thriving and mobile communications will be available to anyone anywhere at low cost 
+&#149; English will be a universal language of global communication but other languages, such as Mandarin, could grow in prominence
+&#149; Virtual reality on the internet will lead to more productivity but will also spawn new addiction problems
+&#149; Humans will remain in charge of technology, even as more activity is automated and 'smart agents' proliferate, and
+&#149; People will wittingly or unwittingly disclose more about themselves, gaining some benefits in the process even as they lose some privacy.
+"Many of these respondents knew from history and personal experience that technologies can have good and bad effects," says Lee Rainie, director of the Pew project.
+"I come away with a sense that the future is still up for grabs, even as everyone agrees that it will be very different from today."
+
+New research suggests that a fall in methane emissions, partly attributed to diminishing wetlands, was only temporary
+China's booming economy and the wetlands of the northern hemisphere have emerged as key factors in what could be a future escalation in emissions of the greenhouse gas methane, according to new research.
+A study of methane emissions published in the journal Nature today reports that atmospheric methane has increased over the past seven years after dropping during the 1990s.
+The paper says China's growing economy, including its flourishing coal industry, may be behind an increase in methane emissions from human activity.
+But this has been offset by a drop in natural emissions from swamps, bogs and wetlands, which are drying out as a result of prolonged drought.
+"If the drying trend is reversed and emissions from wetlands return to normal, atmospheric methane levels may increase again, worsening the problem of climate change," says one of the report's authors, Australian researcher Dr Paul Steele.
+Steele, a senior research scientist at CSIRO Marine and Atmospheric Research, says the paper isn't making any firm predictions.
+"But we are pointing to the prospect [that emissions will increase]" he says.
+The methane menace
+Steele says methane is the second most important greenhouse gas after carbon dioxide.
+Some 6 million tonnes of methane are emitted into the air each year, although the atmosphere can rid itself of some of this through chemical processes, including the oxidative effects of hydroxyl radicals.
+Methane can be emitted as a result of natural or human activity. The primary natural source of methane is rotting wetland vegetation and belching by sheep and cattle.
+It's also produced by decaying landfill and exploitation of fossil fuels, including drilling for oil and coal mining.
+Captured and marketed, methane can be turned into an alternative energy source, but poorly managed it escapes into the atmosphere where it can contribute to global warming.
+It's estimated to have been responsible for a fifth of the enhanced greenhouse effect over the past 200 years, Steele says.
+He says it's unclear how much atmospheric methane comes from natural sources and how much from human activity.
+"We might know the total fairly well but we don't have a very good handle on how to partition the total amongst the range of sources," he says.
+But in an accompanying editorial Dr Jos Lelieveld, director of the Max Planck Institute for Chemistry in Germany, says about two-thirds of global methane currently comes from human activity.
+He says atmospheric methane grew at a rate of more than 10% per decade before 1980 but dropped to almost zero by the 1990s.
+Coal mines and wetlands
+Steele says one of the effects of prolonged drought has been a drying up of wetlands, particularly in the northern hemisphere.
+"Bogs and swamps emit methane because they've got all this rotting decaying vegetation at the base of the water," he says.
+"If they dry up, then the emission of methane stops or slows down." 
+The economic growth and coal mining activity of Asian countries like China, largely driven by the hunger for electricity, appears to be making up for any deficit.
+"Coal mining can release methane to the atmosphere without safeguards," Steele says.
+"We don't know if they're being applied [in China's mines] and to which effect."
+
+This new image of the 'Face on Mars' shows a remnant massif thought to have formed via landslides and debris
+The famous 'Face on Mars', seen by some as evidence of intelligent life on the Red Planet, can now be seen close up.
+The European Space Agency has released new detailed images of the controversial, face-like formation first captured by a Viking orbiter at the Cydonia region of Mars in 1976.
+The face may be a popular target for orbiters - NASA's Mars Global Surveyor snapped images in 1998 and 2001 - but it's not an easy one.
+The site, located at 41&deg; north Martian latitude, is often obscured by atmospheric dust and haze.
+Still, after several attempts, the High Resolution Stereo Camera on board ESA's Mars Express captured a series of images with a ground resolution of approximately 13.7 metres per pixel.
+"These images of the Cydonia region on Mars are truly spectacular," says Dr Agustin Chicarro, ESA Mars Express project scientist.
+"They not only provide a completely fresh and detailed view of an area famous to fans of space myths worldwide, but also provide an impressive close-up over an area of great interest for planetary geologists."
+Chicarro and his team say the high-resolution images further confirm what NASA scientists have been saying for years: it's not a face, but a raised, eroded surface.
+NASA's chief scientist for Mars exploration Dr Jim Garvin describes the formation as the equivalent of a butte or mesa.
+Such formations are common in the Mars region of Cydonia, which is located between the planet's southern highlands and northern plains.
+Convincing the true believers
+But then, some may never be convinced.
+Since the spooky, face-like structure was first photographed by NASA's Viking 1 Orbiter 30 years ago, the site has been the subject of breathless speculation.
+In movies, books and on the web, some have argued this is a massive sculpture built by intelligent life and that surrounding conical-like structures are pyramids, or remnants of a great city, built by a complex civilisation.
+Attempts to say the face is just an accident of geology are often met by claims that scientists have something to hide.
+For example, in response to the NASA images released in 2001, web author Richard Hoagland retorted:
+"The reality is that it is highly unlikely that any of us would recognise a picture of our own grandmother if it was stretched horizontally, flattened, compressed and shown upside down. So of course it doesn't look much like a face."
+'Skull' on Mars
+In addition to the well-known face and 'pyramids' in the region, a previously unseen skull-shaped structure also appears in some of the new Mars Express images.
+Some may be eager to offer up theories to explain this new site.
+Garvin, for his part, doesn't want to discourage anyone from coming up with their own explanations.
+"Please realise that as a scientist of Martian landscapes, my position is that of a traditional scientist, and requires that I utilise the paradigms associated with multiple-working hypotheses grounded in the physics of landscape development," he says.
+"Other opinions on the basis of other approaches are of course welcome and encouraged."
+Alien face or eroded surface, the face on Mars is of interest to planetary geologists like Garvin and these latest images reveal new geological details.
+The latest images show the beginnings of what are called debris aprons, or gentle landslides, surrounding hills. Since the debris apron around the face is minor, the scientists suggest former, larger debris aprons may have been covered by lava flows.
+Meanwhile, the photographs show that the western wall of the face appears to have moved down as a huge mass. The same massive rock movements can be seen at the base of the surrounding pyramid-like formations.
+As for the skull-like formation, Chicarro and his team suggest this is the remnant of an eroded massif. That's their theory, at least.
+
+Dogs like sports celebrities too. They watch other dogs 'play fight' then hang out with the winners
+Dogs seem to enjoy watching other dogs compete against each other and gravitate towards the winners at the end of the game, according to a recent study.
+The UK researchers, who publish their research in the journal Animal Behaviour, believe their discovery is the first demonstration of any animal eavesdropping play.
+In this case, dogs appear to gain information about another dog or human's social status and ability just by watching that individual compete.
+Pooches excitedly rush toward victors when games finish, not unlike enthusiastic human sports fans at a stadium.
+"I believe that within the context of a game, dogs prefer winners because they are likely to be a fun and effective partner with which to play," says lead author Dr Nicola Rooney.
+"One plausible function of play is that it serves as a 'safe context' in which to test one's own competitive ability. An animal will learn more from playing with an able partner than with a lower quality one," adds Rooney, a researcher in the Anthrozoology Institute at the University of Bristol.
+She and colleague Dr John Bradshaw studied 18 canine spectators in a group that included labrador retrievers, springer spaniels and one golden retriever.
+In an initial experiment, a dog was matched with a human competitor in a tug of war contest over a knotted rope toy. Each of the canine spectators was brought in on a leash to view matches.
+For some games, the human competitor made it clear that he or she was playing by performing moves that dogs seem to associate with playtime. 
+These include play bows, where the person gets down on all fours with their forequarters lowered and arms outstretched; forward lunges, where the individual makes sudden, yet non-threatening, movements toward the dog competitor; and feet shuffling, which involves rapid movement of the feet while in a standing position.
+After such competitions, the spectator canine would rapidly approach the human or doggy winner with a cheerful gait holding its ears and tail up, signifying a desire to interact with the victor.
+When playful moves were omitted from matches, dogs were not as attracted to winners, since they probably thought the games were real competitions and the winner might pose a threat.
+During a follow-up experiment, Rooney and Bradshaw repeated the first part of the study, only this time the spectator dog was confined to a crate and only heard the proceedings. 
+After matches, the listeners still gravitated toward the winner, which suggests that audio cues, and possibly other as-yet unidentified cues such as smells, might also allow dogs to identify winners and losers.
+The research was partly funded by the Waltham Centre for Pet Nutrition, the research centre of a popular pet food company.
+In related research, the scientists also determine that dogs like to win games, and that winning seems to improve the animals' social skills, such as their "playful attention-seeking behaviours", Rooney says.
+She therefore advises that dog owners allow their pets to win at least some games, so long as play signals are included in the competitions.
+But not everyone loves a winner. Studies over the past decade on Siamese fighting fish show that fish watching battles are more likely to approach losers than winners, probably because they view the winners as possible rivals.
+
+Characters from Star Trek had similar adventures to the heroes of ancient mythology
+Star Trek heralded real developments in science and drew on the great classical myths, an Australian researcher says.
+Dr Djoymi Baker, a self-confessed Trekkie from the University of Melbourne, watched more than 700 episodes of the cult TV series as part of her PhD.
+Baker, an expert in media and popular culture, says scientists often dismiss science fiction for getting it wrong.
+But she says it can foreshadow or even influence developments in science, adding that more members of the public watch science fiction than "science factual".
+"Because it's gone on for so many decades [Star Trek has] had a big impact on what people think about space and what might be possible in the future," she says.
+"A lot of NASA astronauts cite it as their inspiration; scientists have cited it as their inspiration for new technology."
+For example, NASA's first shuttle of 1977 was named Enterprise after a campaign by Star Trek fans.
+The Star Trek influence can also be seen in new 'spray on' drug delivery technologies, the computer chip and even the flip-top mobile phone and automatic doors, she says.
+And after the catchphrase "beam me up Scotty", scientists have started to experiment with dematerialising and rematerialising helium, and 'cloning' laser beams.
+"They can't beam you up yet but they're starting to do experiments along those lines," Baker says.
+While Star Trek described life in the future, it also had what is now regarded as a quaint pre-Copernican tendency to place humans at the centre of the universe, she says.
+Back to the future
+Baker says Star Trek still holds a huge fascination even as space authorities like NASA fight for funds, recognition and good publicity.
+"Scientists often don't like science fiction because it can get it wrong, but on the other hand it can be very inspirational," she says.
+"NASA might be struggling [but] on the other hand we have science fiction which says we can achieve great things in space, not only in terms of exploration but in terms of what sort of race we want to be, and that's quite a powerful message."
+Baker says Star Trek not only looks forward to the technological future, but harks back to the heroic past of ancient myths like Homer's Odyssey.
+Not only do mythical figures like the Amazons, the god Apollo or the sirens of Homeric lore appear in space, but Star Trek contains the sweeping themes of intrepid adventure and bold exploration that lie at the heart of classical mythology.
+"Mythology is a bit of a recurring theme in science fiction television shows," Baker says.
+"Just as you might have met strange creatures in an ancient myth, instead you find strange creatures in outer space."
+Shows like Star Trek were also an indirect offshoot from the great cinematic "sword and sandal" epics of the 1950s and 60s, she says.
+"Mostly TV was constrained by much tighter budgets so it just couldn't do those types of spectacles," she says.
+"So myth goes into other genres and one of the genres ... is science fiction.
+"Instead of going into the ancient past, you fast forward into the future."
+
+Higher temperatures may change the strength of El Ni&ntilde;os, scientists report
+Earth may be close to the warmest it has been in the past million years, especially in the part of the Pacific Ocean where potentially violent El Ni&ntilde;o weather patterns are born, climate scientists report. 
+This doesn't necessarily mean there will be more frequent El Ni&ntilde;os, which can disrupt normal weather around the world. 
+But it could mean that these wild patterns will be stronger when they occur, says Dr James Hansen of NASA Goddard Institute for Space Studies.
+The El Ni&ntilde;o phenomenon is an important factor in monitoring global warming, according to a paper by Hansen and colleagues in the current issue of the Proceedings of the National Academy of Sciences.
+El Ni&ntilde;os can push temperatures higher than they might ordinarily be. This happened in 1998 when a so-called super-El Ni&ntilde;o helped to heat the Earth to the highest since records began.
+What is significant, the scientists write, is that 2005 is in the same temperature range as 1998, and was among the warmest year ever on record, with no sign of the warm surface water in the eastern equatorial Pacific typical of an El Ni&ntilde;o.
+The waters of the western equatorial Pacific are warmer than in the eastern equatorial Pacific, and the difference in temperature between these two areas could produce greater temperature swings between the normal weather pattern and El Ni&ntilde;o, they write. 
+They blame this phenomenon on climate change, which they say is affecting the surface of the western Pacific before it affects the deeper water. 
+El Ni&ntilde;o and climate change
+Overall, Earth is within 1&deg;C of its highest temperature levels in the past million years, Hansen and the others write.
+They note a recent steep rise in average temperatures, with global surface temperatures increasing about 0.2&deg;C for each of the past three decades. 
+Many scientists attribute this rise to human activities, notably the release into the atmosphere of greenhouse gases that let in sunlight and trap its heat like the glass walls of a greenhouse.
+Human-caused global warming influences El Ni&ntilde;os much as it sways tropical storms, the scientists write. 
+"The effect on frequency of either phenomenon is unclear, depending on many factors, but the intensity of the most powerful events is likely to increase as greenhouse gases increase," they write.
+"Slowing the growth rate of greenhouse gases should diminish the probability of both super-El Ni&ntilde;os and the most intense tropical storms."
+
+In an example of collaborative Middle East science, Israeli and Palestinian researchers are changing female Nile tilapia fish into males to boost food supplies
+Researchers in Israel, the Palestinian territories and Germany want to transform female freshwater fish into males, a sex change they hope will put bigger fish on the dinner table. 
+Male fish are larger, grow faster and weigh about a third more than females, says Assistant Professor Mutaz Qutob, a Palestinian researcher involved in the experiments.
+As part of a project with Hebrew University of Jerusalem and Germany's University of Hohenheim, Qutob and his colleagues will inject compounds from plants found in the occupied West Bank and often used as seasonings into food fed to newborn Nile tilapia fish. 
+"This will have an effect on the fish's metabolic [structure]. It may shift from female to male," says Qutob, a chemist at al-Quds University in East Jerusalem. 
+"This is a very important project. We are introducing a new food source for the Palestinians." 
+Scientists at Hebrew University have previously used synthetic steroids, which are regarded as less healthy, to create male fish, says Dr Berta Sivan, a researcher at the Israeli university, which helped found the project. 
+Palestinians in the West Bank import most of their fish from Israel and the coastal Gaza Strip. 
+But their consumption of fish, especially those from freshwater sources, has fallen in recent years due to rising costs and tighter Israeli travel and trade restrictions on Palestinians. 
+"We wanted to solve a fish-breeding problem in Israel and help bring in and promote fish consumption in the Palestinian Authority," Sivan says. 
+While Israel has been building a controversial separation barrier in the West Bank, cooperation between Israeli and Palestinian academics has been growing over the past few years despite a Palestinian uprising that began in 2000.
+"Israelis and Palestinians who cooperate on research tend to try to work harder during politically critical times," says Professor Hassan Dweik, a co-director of the Israeli-Palestinian Science Organization, which helps find funding for such studies. 
+The organisation this year received 74 proposals for academic projects to be conducted by Israeli and Palestinian researchers on topics related to agriculture, education, the environment and medicine. 
+Israelis and Palestinians usually conduct their research separately and discuss it by phone or online due to the Israeli travel restrictions that also ban most Israelis from entering Palestinian-controlled areas.
+
+This contour map, which illustrates the shape of the poplar panel on which the Mona Lisa was painted, shows there is most warping near the left shoulder
+Leonardo da Vinci's Mona Lisa originally wore a delicate maternity garment and her hair was gathered up in a bun, 3D imaging shows.
+These details, which had disappeared under varnish, have now been revealed using a colour laser scanner that imaged the painting to a resolution finer than the width of a human hair.
+Researchers of the National Research Council Canada (NRC) announced their findings this week.
+"This is the Mona Lisa as we have never seen her before," says NRC president Dr Pierre Coulombe.
+NRC researchers travelled to Paris to conduct the research on probably the Louvre Museum's most viewed painting.
+They did this at the request of the French state museum agency's Centre for Research and Restoration.
+The 3D scans reveal that the woman with the enigmatic smile was originally painted with her hair tied back in a bun, even though today it appears loose on her shoulders.
+The revelation settles an old controversy because only girls or women of bad virtue wore their hair loose in 16th century Italy, says project leader Bruno Mottin from the state museum agency. The real Mona Lisa was a woman of social stature.
+One of her garments, similar to fashions that pregnant or nursing women wore in this period, was also lost under yellow varnish and no longer visible to the naked eye, the infrared scans show. 
+"This is something that had never been seen until now," Mottin says. 
+The real Mona Lisa had three children. Da Vinci was commissioned by wealthy Florentine businessman Francesco del Giocondo to paint his wife between 1503 and 1506 after the birth of their second child.
+But da Vinci kept the painting and worked on it until his death, probably changing her hair and other features.
+In the original Mona Lisa, the subject gripped her chair more tightly, and she is not resting against the back of her chair, as some believed, but sitting upright, the scans show. 
+Researchers also gleaned insights about the da Vinci's painting technique, including his sfumato or smoke technique of soft, heavily shaded modelling, says Mottin. 
+"There is no special mystery in the painting like in [Dan Brown's book] The Da Vinci Code," he says.
+"But in that painting Leonardo tried to capture the essence of life ... It embodies all his skills ... That is the true mystery we've uncovered." 
+Researchers identified a lack of brushstrokes, suggesting that da Vinci may have used his fingers to paint, except there are no fingerprints on the artwork. 
+Scans of the Mona Lisa reveal that darker areas, such as the eyes and corners of her smile, are thicker and "composed of a succession of thinly applied glaze layers", says NRC scientist Fran&ccedil;ois Blais. 
+But how da Vinci actually applied his layers of pigment and oil medium remains a mystery, he says.
+"It's extremely thinly painted and extremely flat, and yet the details of the curls of hair, for example, are extremely distinct. So, the technique is unlike anything we've ever seen before," says John Taylor of the NRC. 
+Split in the painting
+A 12 centimetre split at the top of the painting, which worried curators, appears to be stable, NRC scientists say.
+It was probably caused by the removal of the original frame and repaired between the middle of the 18th and beginning of the 19th century, they say. 
+Also, the poplar wood panel on which da Vinci painted his masterwork has a convex warp on the middle right side that is 12 millimetres higher  than its surroundings, researchers say. 
+But it does not threaten the Mona Lisa smile.
+The 3D scans were done over two nights in October 2004 before the painting was placed in a new glass display case at the Louvre. 
+The scanner recorded the 3D shape and colour of the painting at a resolution of 60 micrometres and a depth of 10 micrometres.
+Mottin says although the Mona Lisa is seen by seven million visitors to the museum a year, scientists have had few opportunities to study her in a laboratory.
+They studied her once in the 1930s, in 1952 and now.
+"She suffers from her celebrity," he says.
+The new images will allow curators to continue their research without touching the canvas, as well as try new restoration techniques on the 3D model before applying them to the actual portrait, says Taylor. 
+The Canadian camera technology has been used to scan Michelangelo's statue David and paintings by artists like Renoir and Corot. 
+It was also used to create animation for Hollywood movies such as Peter Jackson's Lord of the Rings trilogy and on board the NASA space shuttle Atlantis to examine the changing state of the shuttle's heat tiles during a mission.
+
+Downloading information to your mobile phone may be a case of pointing it at a building and clicking
+One day you'll be able to point your mobile phone at a train station, click and download a timetable, or point it at a museum to download a list of exhibits, researchers say.
+That's the idea behind Dr Federico Casalegno's Electronic Lens or eLens project at the Massachusetts Institute of Technology.
+You could also use the phone to contribute to conversation threads, similar to those on internet forums, about a particular business or institution.
+For example, you could submit or retrieve a movie review at a movie theatre.
+"It's a layer of electronic information on physical places," says Casalegno, a research scientist at MIT as well as a user-experience manager at Motorola.
+The approach could change both how institutions deliver information to the public and how people interact with public and private businesses in their neighbourhood.
+Casalegno's idea for the project began with the metaphor of an electronic lens that, when aimed at a building, could become a kind of viewfinder, making the institution more transparent.
+The technology consists of three parts: a barcode-like tag that is placed on places of interest, software called Radioactive that is installed on the mobile phone and the social networking website Constellation.
+To use the system, someone would first stick the tag on a building. 
+For example, the manager of a movie theatre could stick the tag on the outside of the building, then take a picture of it with a mobile phone.
+Next, the manager would launch the Radioactive program, which would ask him or her to name the tag and provide its location. The software automatically locates the tag on a map.
+Then, the manager can create a message that contains text, audio, pictures or video.
+There could be a tag for each movie playing in the theatre, with each tag hosting a movie trailer with show times.
+Viewers with the same software on their phone can access the tag and start a conversation thread with movie reviews.
+The manager can also use the Constellation social networking website to give certain groups access to the tags. Perhaps there is a promotional discount for students of a particular university.
+More than movies
+The technology could work for more than movies. People could place their own tags around town to open up public dialogues about parks or city schools.
+They could even use the tags inside a building, such as a hospital, to provide information to select groups, such as doctors, nurses or visitors.
+"It's very convincing, this idea of connecting social networks with the mobile community," says Leda Guidi, head of the citizens' communication unit for the City of Bologna, Italy, who organised the country's first free municipal internet network.
+Not only does it open up more channels of communication, says Guidi, it could make commerce and government more accessible.
+Casalegno has already conducted a user study of 20 people in Spain and is now working on a new version of eLens to be tested by next year with 100 participants in Boston or Chicago.
+This could mean that soon, pointing and clicking will not be limited to the laptop.
+
+Artist's impression of the core of the telescope
+Australia and Southern Africa have been shortlisted to host a new radio telescope that is 50 times more powerful than any that exist today.
+The shortlist for the international Square Kilometre Array (SKA) telescope was announced in The Netherlands this week.
+The telescope will use low-frequency radio waves to probe deep into the cosmos and aid the study of pulsars, colliding black holes, dark energy and the influence of magnetic fields on the development of stars and galaxies.
+And it will allow detection of any radar signals from extra-terrestrial intelligence that might be lurking in our galaxy.
+"It is going to provide us with a whole new window on the universe," says SKA steering committee member Professor Brian Boyle from CSIRO.
+The SKA telescope is not a single giant instrument but a set of thousands of antennas spread out in a spiral over 3000 kilometres with antennas at the centre closest together.
+In Australia the proposed site for the core of the telescope is at Mileura station, 800 kilometres northeast of Perth in Western Australia. 
+Antennas will be distributed across the continent, possibly extending to New Zealand.
+In Southern Africa, the core of the telescope would be sited in the Northern Cape region of South Africa with dishes extending to Botswana, Namibia, Mozambique, Madagascar, Mauritius, Kenya and Ghana.
+A bid from China was rejected because the proposed site for the core was not flat enough, says Boyle.
+And a joint bid from Argentina and Brazil was eliminated because of turbulent ionospheric conditions above South America that would interfere with the low-frequency radio waves used by the SKA.
+International committee
+Boyle says the shortlist decision was made by the SKA steering committee which has 21 members, including two Australians, one South African and one Chinese member.
+The committee oversees and co-ordinates research and will eventually pull together a single design for the telescope.
+Although some countries have more members on the committee than others, Boyle says the decision was made on a purely scientific and technical basis.
+He also says Australia should be selected as the final site.
+"I passionately believe that Australia is the best site for the SKA from a scientific basis," he says.
+So far Australia has built a small prototype telescope at the core site, called the Mileura Wide-Field Array, supported by US investment.
+The final decision is expected towards the end of the decade and the telescope is expected to cost 1 billion euros (A$1.7 billion) in total.
+Despite the tens of millions already spent on developing SKA technology and telescope design in Australia, and even if it isn't the final location, Australia astronomers will still be ahead, Boyle says.
+He says the money spent has already improved Australia's radio astronomy capability and the effort has developed Australian expertise in radio telescope design and radio astronomy itself.
+And wherever the telescope is built, Boyle says astronomers will be able to access it remotely from their desktop via broadband networks from wherever they are in the world.
+
+Surgeons performing the first zero-gravity operation aboard a plane free-falling to create weightless conditions. They hope this can be a trial run for surgery on astronauts in space
+French doctors this week carried out the world's first operation on a human in zero gravity, using a specially adapted aircraft to simulate conditions in space. 
+During a three-hour flight from Bordeaux in southwest France, the team of surgeons and anaesthetists successfully removed a benign tumour from the forearm of a 46-year-old volunteer. 
+The experiment was part of a program backed by the European Space Agency to develop techniques for performing robotic surgery aboard the International Space Station or at a future Moon base. 
+"We weren't trying to perform technical feats but to carry out a feasibility test ... Now we know that a human being can be operated on in space without too many difficulties," says team leader Dr Dominique Martin.
+Under normal ground conditions, the operation would be a straightforward procedure performed under a local anaesthetic.
+Without gravity, the surgeons' work is harder and the patient's body reacts differently. 
+"Cardiac output is reduced, which creates vascular stress. Blood doesn't pump in the same way. Above all it flows out of a wound in spheres, so we had to create a special vacuum aspirator to contain it," Martin told the French newspaper Liberation.
+The custom-designed Airbus 300 aircraft, dubbed Zero-G, performed a series of parabolic swoops, creating between 20 seconds of weightlessness at the top of each curve. The process was repeated 32 times.
+Strapped inside a custom-made operating block, three surgeons and two anaesthetists worked during these brief bursts, with their instruments held in place with magnets around the patient's stretcher. 
+"If we had had two hours of zero gravity at a stretch, we could have removed an appendix," says Martin, head of Bordeaux University Hospital's plastic surgery unit.
+A similar experiment was carried out in October 2003. But the operation then was to mend a 0.5-millimetre-wide artery in a rat's tail.
+The next phase of the program is to carry out a remote-controlled operation using a robot controlled from the ground by satellite.
+This experiment should take place within a year, Martin says. 
+Anaesthetist Dr Laurent de Coninck says that zero-gravity surgery offers huge promise for space exploration, although it would at first be limited to treating simple injuries.
+"Today more than 400 people have already travelled into space. The chances of injuries occurring during missions will become ever greater and to bring a wounded person back to Earth for treatment is both risky for them and expensive," he says. 
+World space agencies hope that by 2020 a permanently inhabited base can be established on the Moon, to conduct research and exploit lunar resources.
+Researchers would learn to live off the lunar land and test technologies for voyages to Mars. 
+In the shorter term, pre-built robotic surgical blocks could also have valuable uses here on Earth, for instance inside caves or locations that are difficult to access, such as after an earthquake. 
+"Long-distance flights to Mars will not be happening in the immediate future," says Guy Laslandes, head of the Ariane V program at France's National Centre for Space Studies.
+"But the experiment will allow the development of working methods and miniaturised tools that can be used in extreme conditions on Earth, such as during missions to the North Pole."
+
+This Costa Rican zebra tarantula has an archaic way of sticking to surfaces
+Tarantulas secrete sticky silk from their feet to help them adhere to shiny surfaces, says an international team of scientists. 
+Spiders are already known to have two mechanisms that allow them to walk upside or cling to smooth vertical surfaces.
+One is the use of thousands of tiny hairs that generate a weak electrical bond, using van der Waals forces, with the surface. Another is tiny claws that lock onto rough surfaces.
+But scientists at the Max Planck Institute for Metals Research in Stuttgart and US colleagues have now found, in tarantulas at least, there is a third gripping tool.
+Tarantulas have microscopic nozzle-like structures on their feet that secrete a viscous silk-like filament.
+The researchers report their results today in the journal Nature.
+The team carried out its research with zebra tarantulas (Aphonopelma seemanni) from Costa Rica, which were induced to walk around a slick, vertical glass surface.
+To walk up, the spiders used their distal claws to keep a grip. 
+To walk down, they exuded fibres between 0.2 and 1.0 micrometres in diameter from all four pairs of feet that adhered to the glass and stopped them sliding and falling.
+The German team, led by Dr Stanislav Gorb at the institute's evolutionary biomaterials group, says the new discovery raises questions about spiders' evolutionary past. 
+Arachnids also have an abdominal pouch, a spinneret, which produces the silk to make webs. 
+Gorb theorises that spiders may have started making silk with their feet before they began to do so with their spinnerets, as this would have helped their survival by avoiding catastrophic falls. 
+The next step is to carry out a genetic analysis of the foot silk proteins to compare it to the spinneret silk proteins.
+Industrial chemists study spider silk as they are eager to make a synthetic copy that mimics its strength and resilience.
+
+Since ancient times, people have dyed their grey hair black
+A 2000-year-old recipe for hair dye shows Ancient Greeks and Romans used nanotechnology to permanently colour grey hair black, say experts.
+Dr Philippe Walter of the French state museum agency's Centre for Research and Restoration and colleagues report their findings online in the journal Nano Letters.
+The researchers made up a batch of dye according to a recipe used since Greco-Roman times, which includes a mixture of lead oxide and slaked lime.
+They soaked 50 milligrams of blond human hair in the dye for three days, then studied the hair closely.
+The hair turned progressively black and when the researchers took cross-sections of hair and studied it under the microscope they found nanocrystals of lead sulfide inside the hair shaft.
+The lead in the lead oxide had reacted with sulfur from the amino acids found in hair keratins, the scientists say, giving the black colour.
+They say the 5 nanometre lead sulfide crystals look very much like lead sulfide quantum dots that are made today by advanced materials science methods.
+The researchers say their discovery might help develop new mineral-based nanomaterials.
+Dr Ivan Kempson, a materials scientist and research fellow at the University of South Australia, is impressed with the research.
+"It's the highest resolution and most detailed study of the incorporation of a metal like lead into hair," he says.
+Kempson says the findings are interesting for his own work, which looks at how hair takes up metals from the environment.
+But he says it is not yet clear how the sulfur in the keratin is made available to interact with the lead in the hair.
+Kempson says the research is also of interest to the cosmetics industry in developing hair dyes.
+"If you know how they penetrate the hair and how they react within the hair then you can develop better cosmetic products," he says.
+The research team includes a member from L'Or&eacute;al cosmetics company.
+
+One day you might be greeted by a talking, thinking computer-animated face like this one when booking a ticket, or withdrawing money from the bank
+Talking, thinking cartoon faces that understand our needs may one day improve our chances of getting what we want from computers, say experts.
+The animated faces may replace the mouse, keyboard and the touch screen as the main way we interact with computers, say when booking tickets or withdrawing money from the bank.
+Professor Denis Burnham, director of the MARCS Auditory Laboratories at the University of Western Sydney, says a talking, thinking head could be available in the next 10 years.
+"At the moment we use keyboards and mouses [to communicate]," says Burnham, a behavioural psychologist.
+"[But] what people really want with computers is that they actually understand what you're doing and know what you want and can interact with you a lot more effectively and naturally."
+Burnham is heading up a new A$3.4 million (US$2.5 million) project, funded by the Australian Research Council and the National Health and Medical Research Council, to develop a computer-generated head that emulates face-to-face conversation.
+Burnham's team will use technologies such as computer animation, speech recognition and computer-generated dialogue to construct the talking, thinking head.
+And the researchers will use cognitive science to evaluate and improve how well it communicates.
+Frustrated?
+From the word processor's irritating 'paper clip man' to frustrating telephone automated directory services, success so far in this arena has been somewhat limited.
+Burnham hopes his team's talking, thinking head will make our conversations with artifically intelligent machines more effective for two reasons.
+First, it will include visual cues, such as different mouth shapes and face expressions that help us understand what is being said. 
+Second, the head will be capable of tailoring its communication to different types of people, by accessing different databases. 
+It would select articulation, intonation, facial expression or vocabulary to best suit the person it's talking to, says Burnham.
+He says such a head on a videophone could make automated directory assistance more effective at communicating with children, or people with accents or hearing disabilities.
+It might also remember different individuals and personalise its interactions with them, and have appropriate emotional responses when the need arises, Burnham says.
+The head might even "switch to sympathetic mode" when we get irate with it for not understanding us correctly.
+Learning all the time
+Burnham says he plans to develop a head that is also able to learn from its interactions with different people and improve its communication.
+He says current prototype heads are used in tourist information kiosks, for ticketing and language instruction.
+One project is also exploring the use of a talking, thinking head as a personal companion and minder for elderly or disabled people.
+Burnham says the project will initially explore two scenarios where the head might be useful: dealing with billing complaints and language tuition.
+
+Dust mites and their faeces contain an enzyme that destroys the protective function of the skin, leaving it open to other irritants
+Dust mites, which infest the cleanest homes and thrive in bedding and carpets, disrupt the protective function of the skin, a study has found.
+This leaves it vulnerable to other allergens and irritants in the environment.
+House dust mites and their droppings have long been linked to asthma and eczema attacks, and researchers in Japan say they think they know why.
+In a paper to be published in the Journal of Investigative Dermatology, the researchers found that mites and their faeces contain an enzyme, which destroys the protective function of the skin, leaving it vulnerable to other irritants.
+"People go to hospital only after they develop severe [skin] disease, but little is known as to what happened or what caused it," says Assistant Professor Toshiro Takai of the Atopy Research Centre at the Juntendo University School of Medicine in Tokyo.
+"Our study suggests that it may be due to the disruption of the barrier function of the skin [by the dust mite]." 
+In their experiment, the scientists dabbed hairless mice with a solution containing the mite enzyme and observed that the rodents soon suffered water loss from their skins. 
+They then dabbed the mice with riboflavin, or vitamin B2, which is accepted in the scientific community as a substitute for allergens and irritants in the environment.
+"We observed in the mice transepidermal water loss, which is an indication of disruption of the skin barrier. We also observed the penetration of riboflavin into the skin," Takai says. 
+Takai says the finding provides an explanation for skin-related allergies in humans and he hopes dermatologists would investigate more closely into the role of the dust mite.
+"In a healthy person, the barrier is complete and irritants can't get into the skin. But partial disruption of the barrier facilitates passage of allergens and other irritants," he says. 
+According to the World Health Organization (WHO), asthma affected 300 million people worldwide in 2005, killing 255,000 of them.
+The death figure is expected to increase by 20% in 10 years' time if urgent action if not taken, the WHO says.
+
+Say cheese
+Research that calculates the number of photos you need to take to make sure no one in the group has their eyes closed has won two Australians an Ig Nobel award.
+Nic Svenson and Dr Piers Barnes of CSIRO Industrial Physics have been awarded the  Ig Nobel Prize for mathematics at a ceremony at Harvard University.
+"I end up doing a lot of group photographs and the number of people blinking in photographs is driving me nuts," says Svenson, a CSIRO communications officer.
+So she thought there had to be some kind of rule to figure out how many photographs to take to make sure she got a good one.
+Svenson researched basic information on how long a blink lasts, how many times people blink per minute and how fast camera shutters go.
+Barnes, a physicist, worked out that blinks are random and that one person's blinks don't influence another person's blinks. And unless you have got something stuck in your eye, your blinks don't influence each other either.
+"He came up with a graph showing the probability of having someone blink in a photograph," says Svenson. 
+"Then he was able to do the reverse of that equation, as it were, to come up with the number of photographs to take."
+The two found out that when you're taking photos of a group with fewer than 20 people you divide the number of people by three to get the number of shots you need to take.
+But in bad light the camera shutter is open for longer and this gives people more of a chance to blink while a photo is taken. So in bad light you need to divide the number of people by two to get the number of shots.
+As the size of the group increases, the number of shots you need to take increases exponentially, says Svenson.
+And by the time there are around 50 people in the group, she says you can "kiss your hopes of an unspoilt photo goodbye".
+Fingernails scraping on a blackboard
+The winner for the Ig Nobel prize for acoustics went to three scientists who investigated responses to the sound of fingernails scraping on a blackboard. 
+The study, called 'Psychoacoustics of a chilling sound', found that scraping fingernails was the most annoying sound out of 16 sounds tested.
+It was much more annoying, for example, than the sound of a dragged stool, a metal drawer being opened, scraping wood, scraping metal or rubbing together two pieces of polystyrene foam.
+The research, which was published in the journal Perception and Psychoacoustics in the 1980s, concludes that "acoustic energy in the middle range of frequencies audible to humans" is the culprit.
+But it could not answer why such sounds were so grating to the ear.
+Teen repellents and headache-free woodpeckers
+Still on acoustics, the Ig Nobel peace prize went to the developers of a device that makes an annoying noise that teenagers can hear but not adults. 
+The device, which emits a super-high-pitched mosquito-like buzz, was originally used as an electromechanical teenager repellent and later used for telephone ringtones that teenagers could hear but not their teachers.
+Still on mosquitoes, the Ig Nobel prize for biology went to researchers who reported in The Lancet that the female malaria mosquito, Anopheles gambiae, is attracted to the smell of Limburger cheese just as much as to the smell of human feet.
+The Ig Nobel prize for medicine went to the authors of case reports in medical journals on the 'Termination of intractable hiccups with digital rectal massage'.
+The winner of the Ig Nobel prize for ornithology was a professor of ophthalmology who helped explain why woodpeckers don't get headaches.
+The Ig Nobel prizes honour achievements that first make people laugh and then make them think.
+They are produced by the science humour magazine, The Annals of Improbable Research.
+
+Mature cells retain the genetic capacity to grow into all cell types needed to regenerate an entire organism, scientists say
+Scientists say they have cloned mice from white blood cells with a similar technique used to create Dolly the sheep.
+The US researchers, who publish their results online in the journal Nature Genetics, say their method shows it is possible to clone animals from mature cells.
+They say their findings counter the argument that truly mature tissue is too old to be regenerated.
+Dr Jerry Yang of the University of Connecticut, Dr Tao Cheng of the University of Pittsburgh, and colleagues cloned mice using fully differentiated, or mature, white blood cells called granulocytes. 
+They used somatic cell nuclear transfer, in which the nucleus from a cell of the animal to be cloned is injected into an egg whose nucleus has been removed.
+This process works very poorly in mice and usually a two-step procedure is needed: first growing tiny embryos, then removing their embryonic stem cells to generate mouse pups. 
+Yang's team tried cloning using the blood cells at various levels of development, from the stem cells stage through to full maturity, called full differentiation.
+"What was surprising, the efficiency went up as we got more differentiated cells," Yang says.
+"That was very, very surprising, very shocking to us." 
+Only the fully mature granulocytes were able to produce two live cloned pups, although both died within a few hours of birth, the researchers report. 
+"Even we were surprised to find fully differentiated cells were more efficient for cloning, because granulocytes are not capable of dividing," Cheng says. 
+"In fact, we repeated our experiments six times just to be sure. Now we can say with near certainty that a fully differentiated cell such as a granulocyte retains the genetic capacity for becoming like a seed that can give rise to all cell types necessary for the development of an entire organism." 
+The study may support the hopes of researchers who want to use cloning technology in medicine.
+Supporters of so-called therapeutic cloning want to some day be able to take a single cell from a patient, perhaps a skin cell, and use it to generate tailor-made tissue or organ transplants. 
+To do so, fully mature cells must maintain the ability to regress and be reprogrammed.
+
+The way we relate to family members is culturally determined. But is this also reflected in brain activity?
+The culture you are born into influences the way your brain works, an Australian conference has heard.
+Juan Dominguez, a PhD student at the University of Melbourne, discussed the effects of 'enculturation' on the human brain at a recent anthropology conference in Cairns.
+The researcher believes different cultures produce different brains and that cultural differences reflect different neurological functioning.
+"In certain societies and cultures there are certain patterns of behaviour, people may make certain evaluations, have certain opinions, there are certain tasks that are culturally specific," he says.
+"We should be able to find that ... the brain would have some sort of bias acquired through exposure to culture."
+Dominguez is piloting a brain scanning study in which he will test how people from different cultures react when they are shown photos of family members.
+He believes the differing kinship relations will be reflected in different types of brain activity.
+Dr Douglas Lewis, a senior lecturer at anthropology who is supervising the work, acknowledges this is a controversial area.
+But Lewis says there is no suggestion that one culture is "smarter" or "better" than another.
+Rather, the emerging science of neuroanthropology suggests that brains within a group can be 'wired' by common experience, just as individual brains become 'wired' by individual experiences.
+"What we're looking for are correlates in the brain that anthropologists have in the past thought of as being cultural or culturally mediated," he says.
+Recognising faces
+The study will test brain function in an Indian Tamil and an Australian of Anglo-Saxon descent.
+He says while western cultures call both maternal and paternal uncles 'uncle', other cultures, including Tamil, call paternal uncles 'father' and reserve 'uncle' for maternal uncles.
+"You may have a distant relationship with your father [and] a closer relationship with your uncle," Dominguez says.
+"This could bias the way in which the way brain develops because the parts that modulate emotions may be engaged in certain ways."
+He'll test this by showing the subjects photographs of relations and monitoring their brain activity with magnetic resonance imaging.
+"We think that there will be patterns of activity that will be different," he says.
+How does experience shape our brain?
+Dominguez says the human brain is 'plastic' and responds to its environment in the way connections form between brain cells.
+These connections are influenced by repeated patterns of thought, emotional reinforcement and even the influence of chemicals associated with stress and pleasure on the brain.
+"The brain is an experience acquisition device that goes beyond genetic constraints," he says. "It is always engaged in generating and pruning connections."
+Lewis says the constant process of wiring and rewiring makes every brain unique.
+"The number of potential connections between neurones in the neocortex alone exceeds the number of atoms in the physical universe," he says.
+"That means there are potentially that many brains ... and we're looking at certain groups or clusters."
+The principle can apply to peer groups and sub-cultures as well.
+"If you're hanging out with the hip-hop scene ... you're going to pick up patterns of thought, ways of thinking, expectations of other people's behaviour that are different from your next door neighbour who's a retired factory worker," he says.
+
+Textiles made from feathers may be lightweight, good insulators and cushion impact
+Chicken feathers and rice straw are being turned into fabric fibres that resemble wool, linen and cotton, scientists say.
+The textiles may help reduce not only agricultural waste but also our reliance on petroleum-based synthetic fabrics.
+"[Some] 50% of all fibres are from petroleum, and we have an oil issue," says Yiqi Yang, a professor of textile science at the University of Nebraska-Lincoln, who is collaborating with doctoral candidate Narendra Reddy.
+Yang and his colleagues think that agricultural waste could offer an alternative source.
+Rice straw is made up of the bits and stems left over after a rice harvest and, like cotton and flax, is composed mostly of cellulose. It now accounts for about 526 million tonnes of waste worldwide.
+Chicken feathers, which are composed of keratin, like wool, make up about 1.8 billion kilograms in waste each year in the US. Much of this material ends up in landfill.
+According to Yang, even processing a small fraction of this agricultural waste and turning it into textiles could have a significant impact on world demand, which totals about 63 million tonnes of fibres a year.
+Yang's team has already conducted research on developing fibres from rice straw.
+"He's a leader in this kind of research," says Jonathan Chen, associate professor at Louisiana State University in Baton Rouge.
+First, collect your rice straw
+Just like cotton, the rice straw is harvested, baled, shipped to a plant and broken down into tiny pieces.
+The straw is treated with a combination of chemicals, heat and enzymes, and washed repeatedly.
+The process breaks down the straw, separating the cellulose fibres from other natural materials.
+These materials include hemicellulose, a carbohydrate, silica, a hard mineral substance, and lignin, a polymer that hardens and strengthens plant cell walls.
+The process of extracting the fibres is under patent review and so Yang is reluctant to describe it in too much detail. But he says that it is not complicated or expensive.
+"The number one challenge is the cost-effectiveness for utilising these kinds of waste materials," says Chen.
+"If you can compete with current available products, you will have a chance."
+Fluffy feathers 
+Research for processing fibres from the chicken feathers is not as advanced as the rice straw research.
+So far, Yang and his team have characterised the fibre properties of feathers to determine the best applications.
+They have focused on the thin, filamentous parts that form the fluffier parts of the feather. These parts have microscopic air pockets interlaced within a honeycomb architecture.
+Those properties could offer fibres that are lightweight, good insulators and cushion impact.
+The biggest hurdle may be getting the textile industry to accept chicken and rice fibres.
+Yang expects the driving force to come from the clothing industry, where people are always looking out for durable, inexpensive, natural textiles.
+
+She might be laughing but her brain is really picking out mismatches
+Laughter involves a unique form of consciousness, says an Australian researcher who is trying to unravel the thought patterns that underpin humour.
+Ann Hale, a medical anthropologist from the University of Sydney, spoke about the social and cultural context of laughter at a recent conference of the Australian Anthropological Society in Cairns.
+She believes jokes rely on the juxtapositioning of two mismatched or incompatible concepts.
+For example, she tells the joke about the prisoner who plays cards with his wardens. But the prisoner cheats, so they kick him out of prison.
+"Prisons have rules that they lock you up," Hale says. "But if you cheat you get kicked out. So you have two concepts there."
+The same applies to slapstick humour, she says.
+When we laugh at someone falling over, it's not the process of falling that tickles our funny bone but the attempt to stay upright.
+"What makes people laugh at slapstick is not falling off the tightrope, but what you do to stay on," she says.
+"We've got an idea that this is what you look like when you're upright and here's somebody trying to stay upright.
+"It's within the same concept but it's incongruous, it's the mismatch ... it's not the fact that you've fallen onto your backside."
+Even babies do it
+Research has shown we instinctively recognise these "incompatible contexts" in the first year of life, Hale says.
+"Research shows that if a mother crawls towards the edge of the cot the baby will laugh because it interferes with the convention that babies crawl, mothers walk," she says.
+It also suggests that we respond to contextual mismatches without having to "get" the joke.
+Hale says these thought processes have been compared to the reactions of highly trained sportspeople, like the tennis player who is in position to return a serve "before the brain kicks in".
+Laughter is essential because it provides a cognitive respite, Hales says.
+"Laughter offers a temporary respite from the everyday clutter of thought. It's a different sort of consciousness with is uncluttered by the everyday 'shoulds' and 'buts'," she says.
+Hale believes laughter is a uniquely human talent that operates within a cultural context but also transcends culture.
+"It's a kind of perception, a recognition," she says.
+"Understanding laughter and humour might get us closer to looking at what consciousness is and [providing] another paradigm."
+
+RNA interference silences genes and so stops DNA from encoding genetic information
+RNA interference, whose discovery brought US scientists Professors Andrew Fire and Craig Mello the Nobel Prize in Medicine, is one of the hottest new areas of biotechnology and has spawned its own mini-industry. 
+The two researchers discovered that certain types of RNA could silence genes, turning them off and altering a cell's functions.
+RNA or ribonucleic acid is the molecule that transmits the genetic information encoded in DNA. 
+Plants use the RNA interference, or RNAi, mechanism to fight off viruses and the discovery is being exploited by labs and companies around the world to try to find cures for cancer, certain types of blindness, and even bird flu. 
+"It's a classic example of basic research which has turned out to uncover a biological mechanism which now has tremendous potential for ... really impacting human health," says Dr Jeremy Berg, head of the US National Institute of General Medical Sciences, which funded Fire and Mello's work. 
+Mello, a professor of molecular medicine at the University of Massachusetts Medical School, and Fire, a professor at Stanford University School of Medicine, made their discovery in the late 1990s.
+In 1998 the pair published their discovery in the journal Nature and in 2002 the journal Science named RNAi as the breakthrough of the year.
+Clinical trials
+Trials using RNA interference to treat people are already under way.
+"It has led to clinical trials on age-related macular degeneration but also there are trials for diabetes and HIV and influenza and most anything you can imagine where we know enough to know that overexpression of particular genes is important," Berg says. 
+"Cancer, for example, is often caused by overactive genes, and quelling their activity could halt the disease," his institute says. 
+RNA interference can also stop HIV, polio, hepatitis C, and other viruses. 
+"It is also an incredibly powerful research tool," Berg adds. Researchers can use it to turn off or turn down a gene and see what happens. 
+Flipping the 'off' switch
+Every cell in the body carries the complete genetic code, written in DNA. These genes cannot all be firing full blast at the same time, so in each type of cell some genes are turned on, or expressing, and most of the others are off. 
+"If you can think of a flood coming out of your kitchen sink to the kitchen floor, today's medicines simply act like a mop and mop up the water. With RNA interference we can shut off the [tap]," says Dr John Maraganore, chief executive of Massachusetts-based Alnylam Pharmaceuticals.
+Alnylam is working with Merck and Co, Medtronic, Novartis, Biogen Idec and the US government to develop RNAi to treat high cholesterol, respiratory syncytial virus, which can endanger infants, H5N1 avian influenza, the Ebola virus and some types of pain. 
+At least 23 different companies are focusing on RNA interference, either for therapy or research.
+But analysts caution that technical problems and safety concerns remain to be resolved before RNAi therapies enter the medical vocabulary. 
+One problem faced by researchers is how to get the interfering RNA molecules into the body effectively, and different companies are taking different approaches.
+Dublin-based company Research and Markets estimated the total value of the RNAi industry at US$1 billion in 2004.
+
+Websites are changing the way musicians promote music and network with other artists
+Musicians tend to hang out with artists who play in a different style rather than those from the same genre, an international study of online social networks has found.
+The study tells us how musical genres evolve and the part that online networking plays in how people produce, promote and listen to music.
+Researchers reporting on the arXiv physics website created two datasets based on information from the music website allmusic.com.
+The first group, which they call the collaboration network, consists of artists who have worked together, such as Mick Jagger and Keith Richards.
+The second group, or similarity network, includes artists who share an element of musical similarity, and puts Mick Jagger in with Tina Turner and David Bowie.
+An analysis of the groups shows little correspondence between artists who play together and artists who make the same sort of music, suggesting that musicians are more likely to collaborate with others from different musical genres.
+"Collaboration is not the mechanism for similarity spreading [and] playing similar music is not an ingredient to predict collaboration links," the authors, from the University of Michigan, the Universitat Pompeu Fabra and the Universidad Rey Juan Carlos in Spain conclude.
+Collaboration networks
+Jean Burgess is an Australian PhD student at the Queensland University of Technology (QUT) who has researched online and offline musician communities.
+She says the study's collaboration network reveals something about the nature of how musical genres evolve.
+"There's no necessary relationship between the style of music you play and who you play music with," Burgess says.
+"Music has always been a really social practice and musicians will tend to work together on more of a social basis.
+"This is how new genres have formed and re-formed throughout history, on the basis of people from different musical styles playing together."
+Burgess says online networking has had a big impact on musicians and how their work is produced, promoted and consumed.
+For example, websites like MySpace and YouTube allow artists to promote their work and network at the same time.
+"The way other MySpace users consume that content feeds back into the formation of social networks," she says.
+Folksonomies
+The second network identified in the study, which is based on musical similarities, reflects another internet-driven development, used commercially by websites like Amazon, says Dr Axel Bruns, also of QUT.
+The authors of the study say this can make it easier for consumers to discover new music.
+But Bruns says it can also potentially result in less choice for consumers.
+"You might end up with a situation where everyone who's a female singer songwriter might get compared to Joni Mitchell [rather than] a lesser known artist who may be a closer comparison," he says.
+Bruns says categorising music by similarity, rather than genre, ties into the new phenomenon of folksonomies.
+"Rather than having a pre-defined ranking which says these singers are rock or alternative or classical ... the categories derive from a broad user base interacting with the data," he says.
+"It's a democratic form of taxonomy which is more in tune with public perception."
+
+This year's ozone loss can be explained by the temperatures above Antarctica reaching the lowest recorded in the area since 1979
+Antarctica in 2006 suffered its highest recorded single-year loss in ozone, says the European Space Agency.
+Ozone measurements made by the agency's Envisat satellite shows a loss of 40 million tonnes on 2 October, exceeding the previous record of 39 million tonnes set in 2000.
+Ozone loss is calculated by measuring the area and depth of the so-called ozone hole in the stratosphere, about 25 kilometres above Earth's surface.
+This year's ozone hole measures 28 million square kilometres, which is nearly as large as in 2000, and the depth of the ozone hole is 100 Dobson units, a measurement of the thickness of the layer, which rivals a record set in 1990, the agency says. 
+Ozone filters out dangerous ultraviolet rays from the Sun that damage vegetation and can cause skin cancer and cataracts. 
+The layer has been badly damaged by industrial chemicals, especially chlorine and chlorofluorocarbons (CFCs), scientists say.
+The chemical reaction that thins ozone reaches its peak with colder high altitude temperatures in the southern hemisphere winter.
+"Such significant ozone loss requires very low temperatures in the stratosphere combined with sunlight," says the agency's atmospheric engineer Dr Claus Zehner. 
+"This year's extreme loss of ozone can be explained by the temperatures above Antarctica reaching the lowest recorded in the area since 1979." 
+Last week, the World Meteorological Organization (WMO) gave notice that the seasonal ozone hole in 2006 was heading for a record. 
+The ozone level globally has lowered by 0.3% a year over the past decade. 
+CFCs, mainly aerosol gases and refrigerants, and other ozone destroyers were  controlled by an international treaty, the Montreal Protocol signed in September 1987. 
+But there is already so much of the pollution stored in the atmosphere that large ozone holes are expected to persist for the next couple of decades, the WMO says. 
+The ozone layer over the Antarctic will only be completely replenished 15 years later than predicted, by 2065, according to the WMO and UN Environment Programme. 
+Ozone in the stratosphere is protective. At ground level, though, ozone, as a chemical reaction between exhaust fumes and sunlight, is a pollutant that can be dangerous for people with bad respiratory or heart problems.
+
+The discovery of cosmic ripples just after the Big Bang explains why the universe is lumpy and not a smooth sheet of matter or energy
+US scientists Dr John Mather and Professor George Smoot have won the 2006 Nobel prize for physics for finding the background radiation that finally nailed down the Big Bang theory of the origin of the universe. 
+The discovery of these 'cosmic ripples' was lauded in 1992 by cosmologist Professor Stephen Hawking as "the greatest discovery of the century, if not of all time".
+While most physicists do not go that far, they are universal in their praise of the experiment, in which the pair and their team designed a satellite and used it to find proof of the Big Bang. 
+Mather, from NASA's Goddard Space Flight Center, and Smoot, from University of California, Berkeley, found faint variations in microwave radiation that dated back to just 300,000 years after the fiery birth of the universe. 
+These ripples in the microwave radiation, they say, were the primordial framework on which the galaxies, stars and other stuff of the universe took shape.
+It explains why the universe is lumpy and not a smooth sheet of matter and energy. 
+"The discovery changed everything," says Professor Lawrence Krauss, a theoretical physicist at Case Western Reserve University in Ohio. 
+"It produced a revolution in what we know about the universe. We know it is expanding, we know it is flat ... and we can measure that to an incredible accuracy," Krauss says. "Cosmology now is a precision science." 
+Until then, theoretical physicists had cobbled together small pieces of evidence that the universe and everything in it had appeared suddenly about 14 billion years ago from an infinitesimally small point in a vacuum of nothingness.
+"There was very strong theoretical prejudice against the Big Bang," Mather says. "The Big Bang was in opposition to the steady state theory." 
+But after the discovery "the adherents of the steady state theory had to give up", he says. 
+Professor Michael Turner, an astronomer and astrophysicist at the University of Chicago says, "It cemented what we call the hot Big Bang model ... It opened the door to this golden age of cosmology that we are now in."
+The findings fit the theoretical models so perfectly that they impressed even astronomers when they saw the first data in 1992, says NASA's Dr Mary Cleave.
+"He actually got a standing ovation when he announced his results," she says. 
+Scientists have since followed up on those measurements to try to understand, for instance, dark matter.
+This is mass that no one has been able to see or measure but which must exist because of the amount of gravity measured in the universe.
+
+Some of the rock art on the Dampier Archipelago
+The public is being asked to comment on plans to protect what's been called the world's largest art gallery, a collection of ancient Aboriginal rock art on the Dampier Archipelago.
+Federal environment and heritage minister Senator Ian Campbell has called for submissions on a proposal that would see most of the area, which is in northwestern Australia, placed on the National Heritage List.
+The proposal would hinder the development of the A$50 billion Pluto Gas natural gas project by Woodside Energy on the Burrup Peninsula.
+The Australian Heritage Council report on the Dampier Archipelago, which the minister released this week, describes the density of rock carvings, or petroglyphs, and stone arrangements on the Dampier as "exceptional".
+It says the depictions of animals, human figures, human-animal figures and geometric designs "provides an outstanding opportunity to develop a scientific understanding of the social functions of motifs".
+And it says the engravings, which date back 30,000 years, provide an "unusual and outstanding visual record" of Aboriginal people's responses to the rise of sea levels at the end of the last ice age.
+During its assessment of the Dampier Archipelago the Council received 20 submissions from industry and state government authorities generally opposed to heritage listing.
+There were only two submissions in favour of listing. One of these was from the local Wong-Goo-Tt-Oo Aboriginal group,  the other from the Australian Rock Art Research Association (AURA).
+"What the minister, basically, in my opinion is looking for, is more support from the public," says Robert Bednarik of AURA, who has been advocating on behalf of the rock art for over 30 years.
+Senator Campbell said last week he was keen to "get the balance right" between allowing industrial development and preserving the rock art.
+"I want to make sure that all of the major stakeholders, particularly the economic stakeholders are very happy with the process and we get what I call a win-win-win," he told ABC Radio.
+In calling for public submissions on the proposed listing the minister drew attention to where the boundary for the protected area should be drawn.
+"Agreeing to the right boundary is a key element of ensuring the heritage and economic values of the area can coexist in to the future," he said.
+But some people are concerned about any compromise that would see some of the rock art sacrificed.
+Bednarik, who is also convenor of the International Federation of Rock Art Organizations, says he spent three years surveying the art on the Dampier Archipelago.
+"You can fairly describe it as the world's largest art gallery," he says.
+Bednarik says the rock art must be preserved as a whole, likening it to the UK's Stonehenge.
+"What if a petrochemical plant said 'Look, you've got here 24 columns, couldn't we take a few out because it's in our way?'"
+The World Monuments Fund has put the Dampier Archipelago on its list of 100 of the world's most endangered sites.
+Opposition to the listing
+Woodside Energy says it welcomes the opportunity to comment on the proposal but will oppose heritage listing.
+"As a general principle we don't doubt that the Burrup is a special place," says a company spokesperson.
+But he says the listing will create uncertainty for industry in the area, which could be held liable for damage to the rock art through pollution. 
+"It wouldn't only hinder our project, it would hinder everything," the spokesperson says.
+He describes the heritage listing as a "blunt instrument" because it fails to consider the economic values of the area that is the gateway to the A$20 billion North West Shelf liquefied natural gas project.
+"This is probably the most productive part of the Australian land mass," he says.
+The spokesperson says the company prefers a management plan for the area produced by a coalition of state and federal government, Indigenous groups, conservationists and industry.
+Comments on the proposal to list the Dampier Archipelago are to be made to the Heritage Assessment Branch of the Department of the Environment and Heritage by 28 November.
+
+A new type of paper made from nanowires withstands temperatures to 700&deg;C
+Tough paper that won't burn, is resistant to bacteria and can be written on time and time again has been developed by US researchers.
+The paper could be used in a range of applications, say scientists from the University of Arkansas in Fayetteville.
+It could be used to make products from reusable bacteria filters to flame-retardant wallpaper that automatically decomposes airborne toxins.
+Alternatively, it could be used to make rewritable, erasable, heat-resistant billboards along highways.
+Its core ingredient is the key to the paper's resilience. While most paper is made from cellulose fibres, the new material is made from nanowires of titanium dioxide, a chemical compound common in white pigment.
+"The starting materials are simple, non-toxic and inexpensive," says Dr Z Ryan Tian, assistant professor of chemistry and biochemistry at the university.
+"The assembly is a room-temperature casting process, as simple as drying paper pulp."
+To make the nanowires, the researchers first mix powdered titanium dioxide with an alkaline solution and place it in a teflon-coated container.
+Then they heat the mixture in an oven at 150-250&deg;C for one to several days.
+As the alkali evaporates, it leaves behind long, white fibres.
+The nanowires are washed in distilled water and, when still the consistency of wet pulp, cast into 3D shapes such as tubes, bowls and cups.
+After the paper dries, it can be bent, folded or trimmed with scissors.
+The finished product can withstand temperatures of 700&deg;C, which makes it flame-retardant. It also makes it possible to sanitise the paper with a torch flame or ultraviolet light.
+The paper's properties also make it ideal for a reusable filter membrane in gas masks, the researchers say.
+The pore size of the paper can be adjusted during the casting process so that the holes are big enough to let oxygen in but small enough to block toxins.
+"This [research] shows a novel way of fabricating membranes made of titanium dioxide nanowires," says Professor Zhong Lin Wang, director for the Center for Nanostructure Characterization and Fabrication at the Georgia Institute of Technology in Atlanta.
+In addition, when photons of light hit the nanoscale fibres, a charge is created that works to zap and destroy any toxins on the surface.
+The team has applied for a patent on the process and is looking for industrial partners to license and commercialise applications of the nanopaper technology.
+
+RNA polymerase, a crucial molecule in the multi-step process that encodes genetic material into proteins. Roger Kornberg published its structure in 2001
+US scientist Professor Roger Kornberg, the son of a Nobel laureate, has won the 2006 Nobel chemistry prize for showing how genetic information stored in genes is copied and then transferred to parts of the cell that produce proteins.
+This process, known as transcription, is essential to how cells develop and life itself.
+Kornberg's prize came 47 years after he watched his father Arthur accept the medicine Nobel in Stockholm for his own gene work.
+The Swedish Academy of Sciences says Kornberg junior's research into how RNA or ribonucleic acid moves genetic information around the cell was of "fundamental medical importance".
+"[It] is a key mechanism to the biological machinery. If it does not work, we die," says Professor Per Ahlberg, a member of the Nobel Committee for Chemistry at the Academy. 
+Dr Elias Zerhouni, director of the US National Institutes of Health, which has helped fund both Kornbergs' work, says understanding the process may help fight disease.
+"Illnesses like cancer, heart disease, and various other kinds of inflammation are linked to disturbances in the transcription process," he says. 
+"Understanding this process in more detail may provide researchers with the needed tools to develop new treatments for diseases." 
+And because the transfer of information helps explain how a cell becomes a nerve or liver or muscle cell, understanding transcription is crucial for the development of various therapeutic applications of stem cells. 
+X-ray crystallography
+If DNA is the blueprint for life, RNA is the builder that has to make something out of it, and Kornberg figured out how this happens.
+He used a process called x-ray crystallography, in which molecules in a chemical reaction are 'frozen' into crystals and photographed using x-rays, to capture transcription in action and in incredible detail.
+These images showed the complex structure of RNA.
+But work was slow, says Kornberg, who is now at Stanford University School of Medicine.
+"It was only possible because of advances in computing."
+Kornberg made an image of a molecule that RNA uses to read and transcribe the DNA code. 
+It took close to 20 years to find a way to first see and then understand the molecule, known as RNA polymerase. 
+"[The process of transcription] is one of the most fundamental biological processes," says Dr Jeremy Berg, director of the National Institute of General Medical Sciences, which helped fund Kornberg's work. 
+"The DNA double helix is a very beautiful structure but it is a challenge to deal with because all the information is inside," Berg says.
+"What RNA polymerase has to do is somehow find the right spot and then pull the two strands of the double helix apart in the right region. 
+"It has to copy the sequence very accurately. It has to stop and start in the right places. It has to turn on the right genes under the right circumstances," Berg adds.
+Kornberg senior was honoured for advancing understanding on how genetic information is transferred from a mother cell to its daughters.
+The award makes the Kornbergs the sixth father-son pair to win Nobels since the prizes were first awarded in 1901 and the eighth set of parent and child laureates.
+
+Artist's impression of an ultra-short period planet circling its star
+Astronomers have discovered a new class of planets outside the solar system that hug their parent stars so tightly they take less than a day to complete an orbit. 
+Using NASA's orbiting Hubble telescope, astronomers found between eight and 16 new planets near the centre of the Milky Way that orbit their parent stars in as little as 10 hours.
+They were looking at part of the Milky Way known as the 'galactic bulge', so-called because it is rich in stars and in the gas and dust that go to make up stars and planets. 
+The scientists publish their findings today in the journal Nature. 
+At 26,000 light-years away, they are the most distant planets yet found and a further indicator others are probably scattered throughout the Milky Way, the researchers say.
+"This allows us to say with a high degree of confidence that there are billions of planets in our galaxy," says Dr Mario Livio, an astronomer at the Space Telescope Science Institute in Baltimore.
+Scientists have long conjectured that planets exist outside our solar system but they have only been able to locate them since 1993. 
+About 200 planets have been discovered so far, many of them gas giants similar to Jupiter locked in a close orbit to their parent stars. 
+Those 'hot Jupiters' can be eight times closer to their parent stars than Mercury is to the Sun. 
+The newly discovered planets fit within that category, except they move even more quickly around their parent stars, which are smaller than the Sun. 
+Surface temperatures on those "ultra-short period planets" are about 1650&deg;C, says Dr Kailash Sahu, a Space Telescope Science Institute astronomer who led the team.
+Their parent stars are so nearby they fill up one-third of the sky from the horizon to the zenith, Sahu says. 
+Sahu's team found the 16 possible planets by looking for stars that dim when planets pass in front of them.
+The researchers confirmed two of those as planets by examining the slight wobble of the parent star caused by the orbiting body's gravity. The other objects were too distant.
+Using other tests, the team was able to say with certainty that "at least a large fraction of our candidates must be planets", Sahu says.
+
+The flowers on this dress open and close by themselves
+A dress with animated flowers on its neckline, shirt sleeves that make sounds in tune with your body language, and a hemline with a mind of its own have been developed by a Canadian researcher.
+Professor Joanna Berzowska and international colleagues will discuss these and other examples of 'wearable technology' at a workshop in Australia next year called reSkin.
+Berzowska's flowery dress, named Kukkia, has a neckline with felt and silk flowers that open and close according to a special electronics embedded in the dress.
+"I really wanted to make these dresses that have personalities, that move and behave almost like animals," says Berzowska, who teaches computation art at Concordia University in Montreal.
+The flower petals are made of silk and felt, and contain thin wires of Nitinol, an alloy of nickel and titanium.
+Nitinol is a 'shape memory alloy', which can be programmed to have different shapes at different temperatures.
+When the wire heats it shrinks and pulls the petals together, closing the flower. As it cools down, the wire relaxes and the petals open.
+A custom electronics board is connected by embroidered conductive thread to the flowers and makes each one open and close every 15 seconds.
+The system is run on rechargeable lithium polymer batteries, originally designed for use in model aeroplanes, which are embedded in pouches in the dress.
+Another dress with a mind of its own is Vilkas, which has a hemline that goes up and down on its own.
+We tend to think of consumer electronics as something we can control. But Berzowska says once you turn on the microcontroller in these dresses, you have to surrender control.
+"I like how perverse it is to have a piece of wearable electronics that you can't control," she says.
+"Perhaps they don't do what you want them to do and they behave in unexpected ways on your body. Maybe they move at inappropriate times."
+Musical pants and sound sleeves
+Berzowska also has musical clothes including musical pants that make a sound every time you take a step.
+"As you're walking through public space you can leave a whole trail of sounds behind you based on how you're walking," she says.
+She also has 'sound sleeves' that produce different sounds to reflect the wearer's body language.
+The sleeves produce a higher frequency sound the harder you squeeze your arms together.
+If someone is feeling angry or threatened they cross their arms causing the sleeves to generated an almost painfully high pitch.
+"But when you relax your arms the pitch goes down," says Berzowska. "It almost sounds like a cat purring."
+Intimate memories
+Berzowska has another outfit called Intimate Memory that record acts of physical intimacy using a microphone and a series of light-emitting diodes (LEDs) stitched in a curved line across the front. 
+The LEDs light up when someone touches the skirt, whispers something in the ear of the wearer, or blows on their neck.
+"The number of lights represents the intensity of the intimacy event similar to the volume indicator on a stereo," says Berzowska.
+"Over time, the lights turn off, one by one, to show time elapsed since the event took place."
+
+The bus-sized monster catching a smaller plesiosaur
+Scientists have found a fossil of a monster fish-like reptile in a 150 million-year-old Jurassic graveyard on an Arctic island off Norway. 
+The Norwegian researchers discovered remains of a total of 28 plesiosaurs and ichthyosaurs at a site on the island of Spitsbergen, about 1300 kilometres from the North Pole.
+At the time these were the top marine predators, when dinosaurs dominated on land.
+"One of them was this gigantic monster, with vertebrae the size of dinner plates and teeth the size of cucumbers," says Dr Joern Hurum, an assistant professor at the University of Oslo.
+"We believe the skeleton is intact and that it's about 10 metres long," he says of the pliosaur, a type of plesiosaur with a short neck and massive skull. The team dubbed the specimen The Monster. 
+Such pliosaurs are known from remains in countries including the UK and Argentina but no complete skeleton has been found, Hurum says.
+The skull of the pliosaur, perhaps a distant relative to Scotland's mythical Loch Ness monster, is among the biggest on record. 
+Scientists will return next year to try to excavate the entire fossil, buried on a hillside. 
+Plesiosaurs, which swam with two sets of flippers, often preyed on smaller dolphin-like ichthyosaurs. All went extinct when the dinosaurs vanished 65 million years ago. 
+The scientists rate the fossil graveyard "one of the most important new sites for marine reptiles to have been discovered in the last several decades". 
+"It is rare to find so many fossils in the same place. Carcasses are food for other animals and usually get torn apart," Hurum says. 
+He thinks the reptiles did not die at the same time in some Jurassic-era cataclysm but died over thousands of years in the same area.
+They then become preserved in what was apparently a deep layer of black mud on the seabed. 
+At that time, the area of Spitsbergen was under water several hundred kilometres further south, around the latitude of Anchorage or Oslo. 
+Hurum says the presence of fossils is also an interesting pointer for geologists hunting for oil and gas deposits in the Barents Sea to the east.
+"A skull we found even smells of petrol," he says.
+
+A healthy start to the day? The way your breakfast cereal is processed may mean you can't properly extract nutrients from it
+The same chemical process that makes breakfast cereal tasty can also make it less nutritious, according to a recent study.
+As a result puffs contain less nutritionally available protein than flakes, researchers report in the journal Food Chemistry.
+The difference is in the cooking technique, the Spanish study suggests.
+In the future, the researchers say their findings may lead to healthier preparation methods for cold cereals and other processed foods.
+Dr Francisco Morales, who led the research, says that a chemical process called the Maillard reaction affects both flavour and nutrition in cereals.
+In the reaction, which is usually induced by heat, sugars and amino acids interact to produce odour and flavour molecules.
+It's what gives many foods their characteristic toasty, golden brown qualities.
+"But it also reduces bioavailability of nutrients and it can lead to the formation of contaminants," says Morales, a scientist at the Instituto del Fr&iacute;o in Madrid. 
+He and his colleagues studied 60 packaged cold cereals, measuring the amount of a chemical produced during the Maillard reaction, furosine. More furosine means less nutritionally available protein.
+The researchers found no significant differences among wheat, rice and corn-based cereals. 
+But flaked cereals tended to have less furosine than puffed varieties. 
+The manufacturing process for flakes and puffs is similar, boiling ingredients followed by drying and toasting.
+But puffs need to be cooked at higher temperatures to get their characteristic airy texture. The higher temperatures fuel a stronger Maillard reaction.
+Surprisingly, cereals with added dietary fibre had the highest furosine levels. 
+Just a sprinkle
+A separate paper published in the same journal hints at a way consumers might compensate if their favourite cereal leaves something to be desired, nutritionally.
+A sprinkle of cinnamon might not improve its protein content, but it might raise its antioxidant levels.
+Antioxidants help the body rid itself of free radicals, which can damage cells. Prior studies have linked free radicals to heart disease, cancer and other health problems.
+Lucy Yu, a professor of nutrition and food science at the University of Maryland, and colleagues looked at the antioxidant properties of several spices and flavourings.
+Cinnamon ranked first in antioxidant strength among the tested flavourings. 
+Rong Tsao, one of Yu's research assistants, says, "Our findings could potentially be used for dietary supplement developers to help determine what spices and herbs could be used in their products for improved antioxidant properties."
+
+You can make music just by flexing your fingers in the air
+Musicians can jam together by making gestures with their fingers in the air, says an Australian researcher.
+Dr Alistair Riddell at the Australian National University has developed a system that allows groups of people to make music with a sensor system that translates finger movement into sound.
+"It's a form of wearable instrument," says Riddell, who will help facilitate a workshop on wearable technology in Canberra next year called reSkin.
+Riddell has already given performances with other musicians using the system.
+"It was a very strange kind of performance because people just looked at you and you were moving your hands in front of them and just basically staring at them," he says.
+Each musician has flexible sensors strapped to both thumbs and six of their fingers.
+As the sensors bend, this changes their electrical resistance, which in turn communicates changes in sound properties such as the type of sound, its pitch, volume, and effect such as echo.
+Each finger involved has between 2 and 100 different positions that corresponded to different parameters, Riddell says.
+Signals are sent to a microcontroller on the musician's back and then on to other computers that build the composition and create the sounds.
+While the idea of creating sound with gesture has been explored previously, Riddell's system is the first to enable more than one person to be involved.
+"We shared the same computational space," he says of the peformances. "It wasn't like we were three musicians with three guitars, we were actually three musicians with one guitar."
+During the performance Riddell hid the technology to maximise dramatic potential.
+"What you really saw were three people standing in front of you with their hands raised in front of them and they were bending their fingers," he says.
+And at the end of the performance the group extended their fingers, brought their arms down by their side and the music stopped.
+Challenges
+Riddell says one of the challenges was attaching the sensors and microcontrollers to the musicians.
+"It's really tricky to put any type of technology close to the skin," he says. "There seems to be some incongruity between technology and our biological wrapping."
+In the end he had special jackets made up to carry the equipment.
+Riddell describes performing with the hand sensor system as enjoyable but very exposing, sometimes embarrassing and surprisingly physically demanding.
+"After 20 minutes or so your hands would really get very sore," he says.
+One of Riddell's collaborators, sound and media artist Somaya Langley, is now working on a similar system that uses accelerometers instead of flex sensors attached to arms instead of fingers.
+As you move your arms in space, their acceleration in time and space is measured. This is linked to sounds produced by a computer that are played through a quadraphonic sound system.
+She says the aim is to be able to throw your arms around in space and be seen to be throwing around a sound.
+"It's kind of like having a virtual sound-object like a beach ball," she says.
+
+The camel, an ancestor of the dromedary, was four metres tall and roamed the Middle East thousands of years earlier than anyone expected
+Remains of a 100,000-year-old giant camel new to science have been found in the Syrian desert, scientists say.
+"It was not known that the dromedary was present in the Middle East more than 10,000 years ago," says Swiss researcher Professor Jean-Marie Le Tensorer of the University of Basel.
+"Can you imagine? The camel's shoulders stood three metres high and it was around four metres tall, as big as a giraffe or an elephant," he says.
+That makes the ancient camel twice as tall as today's dromedaries, or one-humped camels.
+"Nobody knew that such a species had existed," he says. 
+Tensorer, who has been excavating at the desert site in Kowm since 1999, says the first large bones were found some years ago.
+But they were only confirmed as belonging to a camel after more bones from several parts of the same animal were recently discovered.
+"We found the first traces of a big animal in 2003, but we were not sure it was a giant camel," he says. 
+The scientists also found 100,000-year-old human remains nearby.
+Humans apparently killed the camel while it was drinking from a spring, says Tensorer.
+Neanderthal or Homo sapiens?
+"The bone is that of a Homo sapiens, or modern man, but the tooth is extremely archaic, similar to that of a Neanderthal. We don't know yet what it is exactly. Do we have a very old Homo sapiens, or a Neanderthal?" says Tensorer. 
+"We expect to find more bones that would help determine what kind of man it was." 
+Humans have been present in what is now modern Syria for 1.5 million years. The area played a key role in the migration of the first human beings towards Asia and Europe, he says. 
+Kowm, the site where the remains were discovered along with flint and stone weapons, is a 20 kilometre-wide gap between two mountain ranges that had a number of springs.
+The site was first surveyed in the 1960s and evidence of a 1 million-year-old human settlement has been found there.
+Basel University researchers say it is considered a "reference for early prehistory in the Near East".
+It attracted migrating herds, such as antelope, and humans.
+Archaeological layers covering a period of several hundreds of thousands of years were discovered, which is unusual for such an open site, Tensorer says. 
+"It was a savannah more or less," he says. "The camels then ate probably what they eat today."
+
+An active galaxy with a supermassive black hole near its centre spewing out matter across the cosmos
+Our cosmic neighbourhood is flush with supermassive black holes busily devouring nearby stars and other matter, say scientists who have unveiled the first complete census of black hole activity in the local universe.
+The survey, which took nine months of observations with NASA's Swift satellite, was presented at a recent American Astronomical Society meeting in San Francisco.
+The survey uncovered more than 200 supermassive black holes within 400 million light-years of Earth, says Dr Jack Tueller with NASA's Goddard Space Flight Center.
+These objects, also known as active galactic nuclei or AGN, are millions or even billions times as large as the Sun and occupy a region of space about the size of our solar system.
+As they gobble up nearby matter, the black holes generate x-rays and many other forms of energy.
+Other black holes also spew out jets of particles, which a related research project has determined are made up of protons and electrons.
+Despite their violent activity, many AGN are obscured by surrounding gas and dust.
+Swift, a satellite whose main mission is to track gamma-ray bursts, spends its off-hours scanning the sky for high-powered x-rays.
+This radiation can be detected despite light-absorbing material that often hides the black holes.
+"It's hard to believe the whole sky is peppered with black holes," says University of Maryland researcher Dr Craig Markwardt.
+Scientists know that nearly every massive galaxy, including our own Milky Way, has a supermassive black hole near its centre.
+But they do not know why only a few percent appear to be actively consuming matter.
+Most black holes, including our own, are dormant and were not surveyed in the Swift census. But those black holes that are active play a key role in the universe.
+The survey will help scientists understand one of the fundamental processes by which energy is distributed in the universe.
+"You can't understand the universe without understanding black holes," says Dr Richard Mushotzky, also with NASA's Goddard centre.
+"Perhaps as much as 20% of all of the radiated energy in the universe arises in one way or another from AGN activity."
+High-energy jets
+Another phenomenon of black holes is the jetting of highly energetic particles, which are commonly seen radiating from quasars and other objects at nearly the speed of light.
+Scientists have long debated whether the long streams, which can flow for hundreds of thousands of light-years across the sky, contain electrons, their antimatter partners positrons, or a mix of electrons and protons.
+New research concludes the streams are made up of protons and electrons. The jets are believed to be one of the primary methods for redistributing matter and energy in the universe.
+"Black hole jets are one of the great paradoxes in astronomy," says NASA's Dr Rita Sambruna, also with Goddard.
+"How is it that black holes, so efficient at pulling matter in, can also accelerate matter away at near light speed? We still don't know how these jets form. But at least we now have a solid idea about what they're made of."
+
+South Korean protesters burn anti-North Korean banners at a rally in Seoul on 9 October denouncing North Korea's reported nuclear test
+Scientists are taking a wait-and-see attitude after North Korea said it had successfully conducted a nuclear test. 
+Only careful analysis of data returned by seismic or atmospheric sensors will say whether the blast was a success or a damp squib, they say. 
+Nor could they rule out the possibility of a scam, in which North Korea blew up a huge stock of conventional explosives to bolster its claim to have joined the nuclear club. 
+James Acton of Vertic, an independent non-governmental organisation in London that specialises in verification research, notes enormous discrepancies in the estimated size of the blast. 
+The Korea Earthquake Research Centre in South Korea says there was a 3.58-magnitude tremor from North Korea's North Hamgyong province that translated into the equivalent of 800 tonnes of TNT. 
+But Russian defence minister Sergei Ivanov, quoted by the ITAR-TASS news agency, says the strength was 5-15 kilotonnes.
+By comparison, the US atomic bomb that destroyed Hiroshima during World War II released the equivalent of about 12,500 tonnes of TNT. 
+"I've heard from three different sources that [the North Korean blast] was less than one kilotonne," says Acton, a nuclear physicist by training. 
+"This [Russian figure] is not a difference of 10-20% [in the yield]. It's huge. We should wait to see if that Russian statement is confirmed," he says. 
+Acton says that going for a 15 kilotonne yield was "the natural size" for a country trying to test a nuclear weapon.
+Paradoxically, it is easier to make and test a Hiroshima-sized weapon of this size rather than to make a smaller one, which requires mastery of miniaturisation techniques.
+"If it turns out to be less than a kilotonne, it could look very much like a fizzle," a bomb that failed to detonate properly and achieve a full chain reaction, Acton says. 
+Could it be a fake?
+Another theoretical possibility is that North Korea stashed lots of TNT underground and blew it up. 
+"It is possible to tell the difference between a conventional explosion and a nuclear test," says Acton. "The differences are very fine and subtle, and you need time to analyse the signatures." 
+Bruno Seignier, in charge of the analysis and monitoring department at France's Atomic Energy Commission, says a nuclear explosion "has a more instant shockwave than a chemical one". 
+He says that "in a small [seismic] event", picking out such differences would take time.
+"The analysis is complicated because the energy that radiates out is weak compared with the subterranean background noise picked up by detectors. You really have to make a very detailed analysis when you look into such an event." 
+To stage a hoax
+As for the scenario of a hoax, Acton cautions that to detonate a huge quantity of TNT to simulate a nuclear blast is in itself quite difficult.
+It would entail digging a large cavity underground, which would be visible to spy satellites, and requires detonators to be triggered at the same time. 
+In addition to seismic sensors run by national governments, the UN's Comprehensive Nuclear-Test-Ban Treaty Organization in Vienna also has a network of 189 seismic and hydroacoustic monitoring stations designed to detect  nuclear tests. 
+The body is not qualified to make public statements on the nature of the incidents registered by its monitoring systems, and therefore has not confirmed whether or not a nuclear explosion had taken place as claimed by North Korea.
+But the raw data has been passed on to the organisation's 176 member states and to 770 institutions around the world. 
+Telltale signs
+Radioactive particles and gases that can vent from an underground nuclear blast are also telltale signs, providing clues as to the type of material (uranium or plutonium) that was used and to the size of the weapon. 
+Sniffer planes and ground sensors can be used to monitor this airborne evidence. In the case of a totally sealed site, nothing may emerge, though. 
+A third monitoring technique is to use satellites with ground-scanning radars, which record the topography of a test site before and after an event. 
+Movement or subsidence of the soil would be the sign of a big blast.
+
+While the rodent study appears to be successful, many safety tests would be needed before the liquid is used on humans having surgery
+Biodegradable liquids that control bleeding during surgery could dramatically reduce time in the operating theatre, a study says.
+Researchers at the Massachusetts Institute of Technology (MIT) and the University of Hong Kong have developed a liquid composed of small protein fragments that can stop bleeding in wounded rodents within seconds.
+The researchers say this is the first time that nanotechnology, technology at the atomic or molecular scale, has been used to achieve complete haemostasis, the process of stopping bleeding from a damaged blood vessel.
+They say that if this success could be repeated in humans, doctors could have a new tool to combat bleeding, one of the hardest problems in surgery.
+"The time to perform an operation could potentially be reduced by up to 50%," says lead author Dr Rutledge Ellis-Behnke, a research scientist at MIT.
+The findings are reported in the journal Nanomedicine.
+The research shows that when a liquid composed of peptides is applied to open wounds, the peptides assemble into a nanoscale protective barrier gel that seals the wound and halts bleeding.
+Once the injury heals, the gel is broken down into molecules that cells can use as building blocks for tissue repair. 
+Doctors currently have few effective methods to stop bleeding without causing other damage. Current tools include clamps, pressure, cauterisation and sponges.
+In their experiments on hamsters and rats, the researchers applied the liquid to wounds in various types of tissue, including the brain, liver, skin, spinal cord and intestine. 
+"In almost every one of the cases, we were able to immediately stop the bleeding," Ellis-Behnke says.
+The researchers do not know exactly how the solution works. But they suspect that the peptides interact with the extracellular matrix around the cells rather than inducing clotting.
+They say the bleeding stopped too quickly for clotting to be the cause and there were no signs of clotting, including aggregation of platelets.
+
+The Milky Way is about one and a half times more massive than Andromeda, pictured here
+The Milky Way may be the most massive galaxy in the local group and not Andromeda, according to research that overturns decades of thinking.
+University of Cambridge astronomer Dr Mark Wilkinson and colleagues looked at several small dwarf galaxies in the local group, which includes Andromeda, the Milky Way and dozens of smaller galaxies.
+When they estimated Andromeda's mass, they found it less than previously thought, making the Milky Way the heftiest.
+Astronomers determine the mass of galaxies by looking at how fast the stars and the gas in the inner disk are rotating. The faster they move, the more massive the galaxy.
+Until now precise measurements of the rotation of the galaxy's dark halo, which extends for thousands of light-years beyond the galaxy's visible starry disk, have not been possible because there are few visible objects that can be measured. 
+But with the high resolution of the European Southern Observatory's Very Large Telescope, Wilkinson measured the velocities of stars in several extremely faint dwarf galaxies orbiting Andromeda to determine the mass of its dark halo.
+"Although Andromeda's inner disk is moving faster than the Milky Way's, further out in the halo, which is almost exclusively made up of dark matter, the opposite is true," he says.
+"The best fit for the data showed that the Milky Way is about one and a half times more massive than Andromeda." 
+Wilkinson and colleagues posted their findings recently on the arXiv physics website and have submitted the data to the journal Nuclear Physics B.
+Largest but not heaviest
+Last year astronomers suggested that Andromeda might be three times larger than previously thought. But the results are not necessarily contradictory.
+Data from the WM Keck Observatory in Hawaii was used to indicate the extent of the visible disk rather than the mass of the whole galaxy. 
+"We need more data to work out the point at which the mass starts falling off," says Wilkinson.
+"That could tell us more about the profile of dark matter. However this [latest research] is a very small sample, only two out of billions of galaxies, so we need to reduce the error bars."  
+Australian researcher Dr Jeremy Bailin, from Swinburne University of Technology, agrees.
+"It's notoriously difficult to measure the mass of astronomical objects. You can't put a galaxy on a scale," he says.
+"But reducing the uncertainties on mass is important for understanding the history of the local group and will help us better understand how it compares with other groups of galaxies."
+
+A component of the micro gas-turbine engine
+A tiny gas-turbine engine that fits on a 20 cent piece could replace batteries that power laptops, mobile phones, radios and perhaps home generators, its developers say.
+The microengine is being developed by a team led by Alan Epstein, a professor of aeronautics and astronautics at the Massachusetts Institute of Technology.
+He says the engine could provide five times as much power as a laptop battery for the same cost.
+"My laptop battery now runs my computer for about three hours before recharging. A microengine power system, engine plus fuel, with the same weight as the battery should run the laptop for 15 to 20 hours before refuelling," says Epstein.
+The engine works on the same principle as a jet engine. 
+A compressor sucks in air from the outside and compresses the air. Fuel injectors add fuel to the compressed air and the mixture gets ignited.
+Epstein's engine will run on a variety of fuel, including kerosene, propane, ethanol, methanol or hydrogen.
+The hot gas produced expands rapidly to turn a turbine, which turns a coil inside a magnet to generate electricity.
+A jet engine has thousands of parts assembled into the few components that comprise the compressor, combustion chamber and turbine.
+Epstein's microengine only has two parts: a moveable rotor and a stationary structure that together function as the compressor and combustor.
+And this jet engine would fit into a matchbox. The compression chamber is about the size of a pencil eraser, the fuel injectors are pen-point holes and the turbine is about the size of a 10 cent piece.
+Manufacturing on a small scale
+Such teeny components require a much different manufacturing process than large-scale jet engine parts.
+Epstein and his team, like other researchers in this field, turn to the field of microelectromechanical systems, or MEMS, which is used to fabricate miniature devices ranging from computer chips and biological sensors to chemical processors.
+They etch out the parts from wafers of silicon. The etching requires incredible accuracy with little or no room for error.
+"They are bringing the field of MEMs to levels that a few years ago would have seemed impossible," says Carlos Fernandez-Pello, a professor of mechanical engineering at the University of California, Berkeley.
+Like a car engine
+Pello's team is working on a similar micro system that works like a car engine.
+A bigger challenge for Epstein may be getting the individual components to work as a single engine, says Pello.
+At that tiny scale, the heat produced can spread across the whole device, causing parts to expand and not work well.
+But if they can find a way to insulate the combustor from the other components, a final working product would be about the size of a cigarette lighter, with the engine on top and the fuel below.
+"The size of that [cigarette] lighter is the size of two AA batteries. But the time it would give you power, it's potentially 100 times more ... maybe 50 or 60 hours," says Pello.
+Such a microengine would be as safe as a pocket lighter, too, he says.
+How about emissions?
+Epstein says that his microengine will produce one-hundredth the emissions that a rechargeable laptop battery produces indirectly during the recharging stage, as it draws electricity from the grid.
+So far, the microengineered components have been micromachined, tested individually and assembled into the 20 cent piece-sized test engines.
+Now the team has to add fuel and demonstrate a working engine, something Epstein thinks can be accomplished within the next 12 months.
+
+Scientists have used computers to analyse how Shakespeare used certain words and phrases and have come up with a unique linguistic signature
+A computational fingerprint that uniquely characterises William Shakespeare's writing style is helping to dispel any lingering doubts that he penned his own plays.
+The method could analyse not only plays attributed to Shakespeare but anonymous or controversial writings by other authors.
+"People will take these programs and use the design to go to the 19th century and talk about Lord Byron," says Professor Arthur Kinney, director of the Massachusetts Center for Renaissance Studies at the University of Massachusetts, Amherst.
+Kinney leads the research with Australia's Professor Hugh Craig, director of the Centre for Literary and Linguistic Computing at the University of Newcastle.
+The researchers built a massive database containing tens of thousands of words from Shakespeare's works as well the works of other playwrights of his time.
+Then they used a method called computational stylistics to analyse the usage, occurrence, spelling and placement of phrases, as well as common and rare words.
+For example, the word 'gentle' appears almost twice as frequently in works by Shakespeare than in works by other writers. And Shakespearean drama frequently finds the word 'farewell' preceded by 'hail'.
+A computational fingerprint is created from known works and then compared with the fingerprints of unknown works to see if there is a match.
+Doubts
+Controversy over whether Shakespeare, an ordinary, working class man from the countryside, could have authored such remarkable writing began percolating in the middle of the 19th century.
+Those who doubt his ability suggest that another, more educated man, such as the Earl of Oxford, Edward deVere, penned the plays. Why would the Earl attribute them to Shakespeare? To deflect criticism, some claim.
+During the early part of the 1600s, the gathering of a large crowd at a theatre signalled political unrest and made government officials nervous. And Christian groups, such as the Puritans, found the theatre immoral.
+But there has been plenty of evidence to suggest that Shakespeare did write the plays.
+For one, Shakespeare apparently wrote plays until 1611; the Earl of Oxford died in 1601. 
+Also, at least four different publishers put Shakespeare's dramas to print. If he had not been the author, they would have all had to keep the secret.
+"The more people you had to have involved [in the conspiracy], the more likely it would have been that somebody would have blown the whistle," says Professor Gary Taylor, director of History of Text Technologies at Florida State University.
+Kinney and Craig's computational method adds scientific credence to the mix.
+"The more different kinds of data you have pointing to the same conclusion, the more confidence you have in that conclusion," says Taylor.
+The team is writing a book By Me, William Shakespeare, which will be available in late 2007 and will contain their findings.
+
+Fusion reactors rely on plasma, the gas produced by very high temperatures or pressures, such as in the heart of the Sun or in lightning
+Australia is running out of time to be part of the global research effort on nuclear fusion, say experts.
+Dr Matthew Hole of the Australian National University says Australia should be a partner in the International Thermonuclear Experimental Reactor (ITER) in southern France, which is a testbed for a commercial fusion power reactor.
+"The ITER project itself is the world largest science experiment," says Hole, a plasma physicist who is chairing a workshop on fusion and the ITER in Sydney this week.
+Hole says ITER is driving the international agenda in fusion energy research and  Australia should be involved so that it keeps its research capacity in the area, and does not end up having to buy the technology back at great cost.
+He says the seven ITER partners could ratify the final reactor plan as early as December and once these plans are signed off on Australia will be "locked out" of any opportunity to contribute to the reactor construction.
+"It's a very urgent issue," says Hole. "The deadline, if not missed, is approaching being missed."
+"The next opportunity will might be in 10 years time by which time Australia will have no research capability in this area."
+An Australian discovery
+Fusion power reactors have been a dream of many since Australian Sir Mark Oliphant discovered nuclear fusion, the process that powers the Sun and other stars, in 1934.
+Fusion involves the release of energy from the combination of two light atomic nuclei, typically isotopes of hydrogen.
+And it is this energy that scientists hope to harness as a safe, greenhouse-friendly and economic form of power.
+Hole says nuclear fusion would produce energy at a cost comparable to nuclear fission but with an environmental impact comparable to wind power.
+But there are many challenges. Significant energy is required to force two positively charged atomic nuclei together and a plasma gas of the charged particles must be kept hot and dense for long enough to undergo fusion.
+One challenge is how to confine the plasma that must be kept at temperatures around the heat of the Sun.
+Doughnut-shaped magnetic fields
+The ITER will be a fusion reactor called a tokomak, originally designed in Russia but pioneered in the west by Australia.
+The tokomak fuses ions of hydrogen (deuterium and tritium) that are confined in a doughnut-shaped magnetic field at temperatures of up to 100,000,000ºC. 
+Hole says that unlike previous plasma physics experiments, the ITER will produce more energy than it consumes. Under special conditions it will even produce 30 times more energy than it consumes.
+He says various technologies being developed in Australia could contribute to the ITER but despite Australia's early leadership in fusion science, it now risks missing out unless it is officially part of the French-based project.
+Hole says relevant Australian expertise includes the ability to diagnose what is going on in the reactor, including measuring temperatures.
+"Measuring temperatures at 100 million degrees, for example, is no simple exercise," he says.
+Australia also has expertise in developing materials that can handle the high temperatures involved, says Hole.
+Currently, Hole says only A$1.3 million is spent on fusion research in Australia and this should be increased to A$16 million to be competitive with the US and UK commitment.
+Concerns
+But energy commentator, Dr Mark Diesendorf of the Sustainability Centre in Sydney, is concerned that the government could invest in fusion at the expense of other low-greenhouse energy sources that are likely to deliver more quickly.
+Diesendorf says while there could be a big pay-off from fusion, the technology is very risky, with the chance of plasma becoming more unstable the more energy you try to get out of the system.
+
+Anti-North Korea protesters chant slogans at a protest denouncing both the North's nuclear device test, which scientists now say looks like a dud
+More than two days after North Korea claimed to have exploded a nuclear weapon, scientists edged towards the conclusion that the test, if indeed nuclear, was a failure. 
+But a failure is unlikely to derail North Korea's nuclear program and could even help Pyongyang's bomb makers, they warn. 
+Two main sources of scientific evidence are needed to confirm that a blast is nuclear.
+One is the shockwave sent back by ground detectors.
+The other is fallout, radioactive particles or gases, that often escape from an underground test site, even if the tunnel or shaft is sealed tight. 
+But North Korea's blast was so tiny that the seismic wave is almost indistinguishable from routine subterranean background noise, experts say. 
+That means it will take a long time, harnessing supercomputers and the minds of top physicists, to find any telltale spikes that confirm the blast was nuclear, and not say a stockpile of TNT blown up as a hoax. 
+"There is a series of differentiations to be done" to sift out the blast from background noise, says Xavier Clement for France's Atomic Energy Commission. 
+"It is possible that this cannot be done, given the weakness of the signals compared to the background noise," he says. 
+In the absence, so far, of any known radiological evidence, scientists also note the very small size of North Korea's explosion. 
+Only Russia has described the blast as a full-fledged nuclear event, equivalent to 5-15 kilotonnes of TNT.
+Meanwhile the Norwegian institute of seismology Norsar describes it as a "medium-sized bomb" at 1-10 kilotonnes.
+But other national monitors put it at less than 1 kilotonne, with one figure as little as 200 tonnes.
+Such low yields are feasible with a nuclear warhead, but they are traditionally reserved for established members of the nuclear club that have mastered arts of miniaturisation.
+"The easiest size of weapon to build is 10-20 kilotonnes. It's harder to build one that's smaller, and it's harder to build one that's larger," says James Acton of Vertic, an independent UK watchdog that carries out research into the verification of international treaties.
+"It seems to me technically unlikely and politically unlikely that North Korea would have tried to do anything other in its first test than in the 10-20 kilotonne range," says Acton, a Cambridge-educated nuclear physicist.
+"If it was a nuclear test and the yield was less than a kilotonne, it seems to me the evidence is that this test was a fizzle, it was a partially unsuccessful test." 
+Clement agrees. "If it turns out to have been a nuclear test, it's clear that the weakness of the energy release corresponds to an explosion that fell short of what could have been expected," he says. 
+If the test failed, what went wrong? 
+The assumption among experts is that North Korea used plutonium rather than uranium to make its bomb, given the plutonium-making reactor and fuel rods known to be in its possession. 
+Uranium bombs, like Little Boy dropped on Hiroshima in 1945, are bombs that are relatively easy to make, in which a uranium slug is fired into a ball of uranium to achieve critical mass. 
+But plutonium bombs are more complicated. They entail a small ball of plutonium that, like the centre of an onion, is swathed by conventional explosives. 
+These explosives compress the plutonium and fire a neutron into the mass to initiate a chain reaction. 
+But the explosives must be "very, very carefully shaped", and the detonation must be precisely timed to ensure that the neutron is fired at the right time, says Acton. 
+Another possibility, again, still in the realm of hypothesis, is that the material used in the test had impurities of plutonium isotopes that emit neutrons and this caused the chain reaction to start prematurely. 
+Whatever happened, "none of the problems are in any way terminally fatal to the program", cautions Acton. 
+"They will almost certainly have gained information from this test which will have enabled them to build a better weapon next time around."
+
+The way the Earth wobbles on its axis, like a poorly balanced spinning top, influences our climate and therefore species' survival
+Climate change, naturally induced by tiny shifts in Earth's rotational axis and orbit, periodically wipes out species of mammals, a study says.
+Palaeontologists have long puzzled over fossil records that, remarkably, suggest mammal species tend to last around two and a half million years before becoming extinct. 
+Climate experts and biologists led by Jan van Dam at the University of Utrecht in the Netherlands, overlaid a picture of species emergence and extinction with changes that occur in Earth's orbit and axis.
+The Earth's orbit is not a perfect circle. It is slightly elliptical, and the ellipticality itself goes through cycles of change that span roughly 100,000 and 400,000 years. 
+Its axis, likewise, is not perfectly perpendicular but has a slight wobble, rather like a poorly-balanced child's top, which goes through cycles of 21,000 years.
+In addition, the axis, as schoolbooks tell us, is also tilted, and this tilt also varies in a cycle of 41,000 years. 
+These three shifts in Earth's pattern of movement are relatively minor compared with those of other planets. 
+But they can greatly influence the amount of heat and light the Earth receives from the Sun.
+The effect can be amplified, causing global cooling, affecting precipitation patterns and even creating ice ages in higher latitudes, when two or all the cycles peak together. 
+Van Dam's team looked at 132 species of mammal fossils recovered from three sites in Spain, in layers of soil that dated from 24.5 million years ago to 2.5 million years ago. 
+What the researchers looked for were the fossilised teeth of rodents, mainly because these could be spotted and identified much quicker than the remains of other animals.
+They found that rodent species bit the dust in two regular waves.
+One wave of extinction was roughly every 2.4 million years or so and the other was about every million years or so, coinciding with extremes in the cycles of ellipticality, wobble and tilt.
+These were not swift, massive die-outs of the kind that famously wiped out the dinosaurs 65 million years ago, but rather a fade-out of species that could not cope with habitat loss or competition, especially when ice ages kicked in.
+As they became extinct, other species emerged. 
+"At any given time, there would be around 15 [rodent] species in residence," says van Dam.
+"During the extinction waves, about five or six species would disappear over a period of about 100,000 years or so." 
+The paper, which appears today in the journal Nature, is confident that the species turnover among rodents also happened to other mammals and possibly other biological groups too. 
+Astronomical impact "provides a crucial missing piece in the puzzle" of regular species turnover, it says.
+
+Charles Dickens wasn't a doctor but he learned from them, and they learned from him
+Charles Dickens was so good at describing neurological disease in his characters that the symptoms were used word-for-word in medical text books of the day, says an Australian neurologist.
+The 19th century novelist's interpretations of diseases of the nervous system even predated formal medical classification, some by more than a century.
+In a paper to be published in the Journal of Clinical Neuroscience, Dr Kerrie Schoffer of the Austin Hospital in Melbourne says his observations have helped develop our modern understanding of neurological disorders.
+"In Dickens's day, they didn't really understand much about these disorders, things like Tourette syndrome; there was no name for that and no understanding of the biological basis of it," she says. 
+Yet Dickens described details in his novel David Copperfield.
+His description of the tics, teeth grinding and grimaces of the character Mr Bell, now known as symptoms of Tourette syndrome, was published more than 40 years before Gilles de la Tourette clinically described the disorder in 1885.   
+In The Pickwick Papers, Schoffer notes that Dickens links Parkinson's disease and dementia in an old man whose "limbs were shaking with disease and the palsy had fastened on his mind". 
+Restless legs syndrome, a disorder characterised by the compelling need to move the legs, Schoffer observes, is strongly suggested in the sleepy waiter in David Copperfield.
+He had "the fidgets in his legs, and was twisting them, and hitting them and putting them through all kinds of contortions in his small pantry". 
+Schoffer says Dickens also had a keen eye for people unsteady on their feet, with involuntary muscle movement, tremors and sleep problems.
+Dickens had little formal education let alone clinical training. But Schoffer says he had access to people with movement disorders through leading physicians of the day. 
+"Dickens's rise to prominence as an author meant he interacted with high society, which tended to be prominent physicians," Schoffer says.
+"If there's one thing that doctors and writers have in common it is that we both have to observe people very closely. I think Dickens's work is a great model for the interaction between medicine and literature."
+
+Fiddler crabs with blue shells are vulnerable. So when hungry birds are around, they turn muddy brown
+Tiny blue-shelled fiddler crabs change their colour to avoid being eaten by predatory birds, researchers have discovered.
+Scientists have long been intrigued by the crabs' ability to change the colour of their top shell from bright blue to a more subdued, muddy shade.
+But exactly why the crabs change their colour hasn't been clear.
+"When you catch them, for instance, they go dull," says Dr Jochen Zeil from the Australian National University, whose research appears in the Journal of Experimental Biology.
+To find an answer, Zeil and his colleagues studied a particular species of fiddler crab, Uca vomeris, on the mud flats of Australia's northeast coast, south of Townsville.
+"Some populations of these crabs are all very dull, but in other places they are very colourful," Zeil says. "We wanted to understand how this happens."
+The scientists looked at variations between crabs from three different areas: one group was dull coloured, another was colourful and a third group mixed.
+They found differences in the numbers of crab-eating birds near the dull coloured populations.
+"In the places where the crabs were colourful, there were few birds," Zeil says. "But in the others there were more birds actively hunting crabs."
+To confirm these findings, the scientists set up an experimental model to test whether the crabs changed their shell colour in direct response to the threat of being eaten.
+They found two very colourful crabs living close together and set up a kind of wooden screen between them.
+One crab was left to go about its life as normal. But the other was subjected every couple of minutes to the attentions of a pretend bird. In reality, it was a small foam ball suspended on fishing wire.
+Crabs have poor vision, so the approach of the black ball was enough to convince it a bird was coming, Zeil says.
+Within days, that crab had changed its colour to the muddy shade, while the other remained colourful.
+"We could observe that over a couple of days, the crabs did change their colour when they are confronted with this dummy bird," the researcher says.
+Scientists suspect the blue colour of the crabs is normally used to help them identify others living close by, and avoid fights, Zeil says.
+The next step in his research will be to see whether staying dull all the time has any effect on neighbourly relations.
+
+Insect brains might be small but they're inspiring robotics researchers
+An electrical engineer turned biologist, who now spends his time unravelling the workings of insect brains, has won one of Australia's top science prizes.
+Professor Mandyam V Srinivasan of the Australian National University has won the Prime Minister's Prize for Science for work that has applications in the field of robotic vision, for example for autonomous aerial vehicles.
+For over 20 years, Srinivasan has been designing experiments to work out what information honey bees use to take off, land on flowers swaying in the breeze, navigate the world without bumping into things, and find targets.
+"If we can find out what the neural circuits underlying those things are, maybe we can build machines that are much more cognitive," he says.
+Srinivasan says insect eyes are too close together to allow them to use stereovision to work out how far away objects are. 
+Instead he says they rely on measuring how fast objects are moving relative to their eye to work out how far away they are.
+It is this relatively simple strategy, says Srinivasan, that can be reproduced in robotic vehicles.
+So far, aspects of his work have been used to develop autonomous aircraft that can track terrain and keep level as they are flying.
+The research has also helped develop wheeled robots that can navigate down narrow corridors, and a panoramic imaging and surveillance system which, like an insect eye, can capture almost the entire environment around it.
+Angry bees
+Srinivasan says that over the next five years he wants to shift his focus to studying how angry honeybees that are defending their hive rapidly track down moving targets to sting them.
+"We find it a fascinating example of an exquisitely honed system to chase and intercept moving targets," he says.
+He will use high-speed video cameras to track in 3D how angry bees approach and intercept their target.
+Srinivasan hopes the information on bees' visual cues will help him develop an experiment in which one model aircraft can detect, track and intercept another.
+About half of Srinivasan's funding comes from the Australian Research Council and half from military sources, including the US Defense Advanced Research Projects Agency.
+Other prizes
+Another prize goes to CSIRO-based astronomer Dr Naomi McClure-Griffiths, who wins the Malcolm McIntosh Prize for Physical Scientist of the Year.
+McClure-Griffiths has been studying the shape of the Milky Way and has discovered a new spiral arm, changing many long-held ideas about the evolution of our galaxy.
+The Science Minister's Prize for Life Scientist of the Year goes to Dr James Whisstock of Monash University for his investigation of serpins, which control the break down of damaged cells by proteases.
+Anna Davis of Casimir Catholic College in Sydney and Marjorie Colville of Perth Primary School near Launceston win prizes for excellence in science teaching.
+
+Siberian lakes with peatlands
+Massive peat bogs in Siberia and elsewhere may have helped spur global warming at the end of the last ice age some 12,000 years ago, scientists report. 
+The ice was already melting when the bogs formed, but the fact that they emitted the greenhouse gas methane accelerated the warming trend, says Professor Glen MacDonald, a climate change expert at the University of California Los Angeles. 
+But this does not take humans off the hook, given that the amount of methane sent into the atmosphere since the start of the Industrial Revolution is far higher than what occurred naturally from decomposing material in the old bogs, he says. 
+"The amount of methane that we have added to the atmosphere is even more extreme than the rate of this change that happened at end of the last ice age," says MacDonald, the lead author of a study published today in the journal Science.
+"Over the last 200 years we have more than doubled the amount of methane in the air." 
+At the close of the last ice age, some 12,000 years ago, the bogs "really turned on", says MacDonald, whose collaborators included those from the Russian Academy of Sciences.
+The bogs caused a rise in the atmosphere's methane level from 450 to 750 parts per billion by volume. 
+But from the year 1750 until the present, he says, methane levels went from 750 to 1700 parts per billion.
+How much is down to humans?
+"About 60% of the methane going into the atmosphere is anthropogenic," or human-caused, MacDonald says.
+"Natural sources today aren't really capable of producing the spike that we're seeing. Methane has reached levels that are unprecedented." 
+Methane occurs widely in nature when bacteria help decompose plant and animal material, without the benefit of oxygen.
+This happens in big bogs, which are made up of a thick layer of incompletely rotted dead organic matter beneath a layer of living vegetation. 
+By taking core samples of peat bogs in Siberia, and adding that data to samples of other peat bogs, the scientists determined that these peatlands formed a bit before the end of the last ice age, but really grew explosively as it ended.
+Methane is said to be up to 23 times more potent as a greenhouse gas than carbon dioxide, so knowing a potential source of methane is important, the researchers say.
+
+Dragonflies were as large as seagulls 300 million years ago, just before the dinosaurs came on the scene
+The enormous dragonflies, millipedes and other insects that lived 300 million years ago grew so large because of Earth's rich oxygen supply at the time, according to a new study.
+"Why isn't there a cockroach that ate Dallas from recent history?" asks co-author Professor Jon Harrison of Arizona State University. "We can answer that question without a time machine."
+Harrison and his team analysed how modern insects are designed for the fact that air today is 21% oxygen.
+They focused on the tracheal system, the interconnected tubes that transport oxygen throughout bug bodies.
+By extension, the researchers envisioned what insects would have looked like millions of years ago when the air was 35% oxygen.
+Their findings help to explain the remains of millipedes over a metre long, 10 centimetre cockroaches and dragonflies with 75 centimetre wingspans dating to the late Palaeozoic period, just before dinosaurs came on the scene.
+Using x-ray imaging, the scientists compared the tracheal dimensions of four modern beetles ranging in size from 3 millimetres to 3.5 centimetres.
+They found that the tracheal system took up 20% more of the insect's body in larger beetles. In other words, the bigger an insect, the more it must invest in air tubing.
+And "more tracheae ... mean less space for everything else in the body, such as the brain and reproductive system", Harrison explains.
+In the oxygen-rich world of the Palaeozoic era, insects needed less air to meet their oxygen needs. As a result, they could afford smaller trachea than modern insects. 
+The researchers conclude that although Palaeozoic insects had the same basic body structure as modern insects, their maximum body size was larger because smaller trachea left more room for the other essential body parts necessary to sustain their weight.
+The findings were presented at this week's American Physiological Society conference in Virginia Beach.
+Dr Steve Heydon, curator and collections manager of the Bohart Museum of Entomology at University of California, Davis, says that the new explanation is plausible.
+But there are other possible explanations for why insects grew smaller, such as competition pressure from birds.
+"Remember that there weren't any birds in the sky when the giant insects were out," says Heydon. "When flying dinosaurs and birds came around, the insects lost their exclusivity."
+
+What a shocker of a hairdo! But would you blurt this out in front of her?
+Older people accused of being 'blunt' can blame their deteriorating brain for their straight talking, an Australian researcher suggests.
+Associate Professor Bill von Hippel, a psychologist at the University of New South Wales, says this deterioration means the brain can't properly inhibit older people from saying inappropriate things.
+"Older adults tend to be more likely to ask about private or personal issues in public than younger adults are," says von Hippel. 
+"And we have suggestive evidence that this is brought about by declines in frontal lobe functioning."
+He was recently awarded an Australian Research Council grant to investigate the theory and the implications for older people's health.
+Von Hippel says the stereotype is that people over the age of 65 are more likely to speak their mind because they have earned the right to, and because they are often seen as a source of wisdom.
+But he says they can lose friends as it can be socially inappropriate.
+"If I'm asking you about your haemorrhoids in public, even if I don't mean to be mean by doing it, I'm nevertheless humiliating you and I'm not providing you with positive emotional support," he says.
+And this can be a health issue, says von Hippel, because losing friends can lead to loneliness, which is bad for both mental and physical health, especially in older people.
+Experiments
+In recent experiments, von Hippel interviewed 80 people from several groups of older and younger adults about the likelihood that other members of the group were likely to say certain inappropriate things.
+He found that older people were more likely to ask in public if someone had put on weight, about their haemorrhoids, or whether they were still having problems with their partner.
+He then tested how well the same people inhibited themselves, an ability controlled by the frontal lobes, by answering trick trivia questions.
+For example, they were asked 'What colour are tigers' spots?'
+He found that younger people were more likely to restrain themselves from answering the trick question, whereas older people were more likely to blurt out 'black' and then realise it was a trick.
+Von Hippel says evidence from these two experiments shows that the same older people, who were more likely to be blunt, have lower inhibitory power in their frontal lobes.
+Future studies
+Von Hippel would now like to do similar tests on a larger number of people using magnetic resonance imaging, or MRI, to check if atrophy in the frontal lobes correlates with bluntness in older adults.
+For now, he can not rule out other causes for the bluntness, such as early stage dementia.
+But he says the frontal lobe theory is supported by other research showing the people with frontal lobe brain damage are often more socially inappropriate.
+An uncomfortable idea?
+But von Hippel says his work has been criticised.
+"I think it's perceived as an attack on older adults," he says. "I don't believe it is."
+He says it is already accepted that atrophy of the frontal lobes occurs as you age and this affects memory and slows down brain processing. 
+"What our research is showing is that there are social consequences as well."
+
+As water falls on the jacket you get a pattern of lights that looks like water falling
+A coat that glows when it rains has been created by a US-based designer.
+Elise Co, of design and technology firm Aeolab in Los Angeles, will be discussing the latest version of her Puddlejumper coat at a textiles show in France this month.
+Puddlejumper is a luminescent, nylon raincoat that turns the prospect of walking in the rain into an opportunity for play and performance, says Co, a former professor of new media.
+It's coated with PVC and has water sensors on its back and left sleeve.
+The sensors are wired via interior electronics to electroluminescent panels on the front of the jacket.
+When water hits one of the sensors, the corresponding lamp lights up on the front, creating a flickering pattern of illumination that mirrors the rhythm of rainfall, says Co.
+"You get a pattern of lights that really looks like water falling," she says.
+Co says the electroluminescent panels are of the same kind of material used as backlighting for phones. 
+The material is usually purchased pre-manufactured as plastic sheets that are cut up and wired together.
+But Co mixed up the chemicals that make the panels and silk-screened them onto the jacket by hand, and hand printed the water sensors onto the jacket.
+Co will help facilitate a workshop on wearable technology in Canberra next year called reSkin, where she will discuss her work.
+"Although technology has the bad rap of being dry or technical, at the very least, intimidating, it is great to illuminate how creative a process it is, and how doable," she says.
+"I especially like the mixture of wearable plus technology because clothing and accessories on the body are so expressive and design oriented, not only visually but also in terms of materiality and usability and wearability."
+Co says her raincoats are still prototypes but the fact they are made of industrial materials mean they could be developed further.
+"There is no reason why they couldn't be made durable enough to be worn normally," she says.
+"It would be a matter of doing tests and tweaking the construction process to make sure they're protected well."
+
+Caffeine is more likely to disrupt a daytime snooze than a normal night's sleep
+Shiftworkers or people with jet lag who drink coffee to keep themselves awake may not be able to catnap the next day, say Canadian researchers.
+They report online in the journal Neuropsychopharmacology that caffeine has a stronger disruptive effect on daytime, catch-up sleep after a night of sleep deprivation than it does on a normal night's sleep.
+"Recent studies have suggested that caffeine is a measure of choice to counteract the effects of sleep deprivation on alertness and performance," say Dr Julie Carrier of Montreal's Sacred Heart Hospital and colleagues. 
+"Our results suggest that this recommendation should be made with caution since using caffeine before sleeping at an abnormal circadian phase, such as during night work, might have more adverse consequences on sleep quality than before sleeping at a normal circadian time." 
+Drinking caffeine at night is known to make it more difficult to fall asleep and to worsen sleep quality, Carrier and her team note.
+They hypothesised that caffeine would have an even stronger effect when people were trying to recover from sleep deprivation by snoozing during the day.
+To investigate, they asked 34 people drink caffeine or placebo before going to sleep at their normal bedtime.
+A month later, the same people were deprived of sleep for an entire night. They were then told to fall asleep an hour after their normal wake-up time, after being given placebo or caffeine.
+People received 100 milligrams of caffeine or placebo before their scheduled morning or evening bedtime, and then another 100 milligrams (or placebo) one hour before.
+Sleeping after caffeine
+All study participants who took caffeine took longer to fall asleep and spent more time in lighter stage 1 sleep and less time in deeper stage 2 and slow-wave sleep, the researchers found.
+But people given caffeine before daytime sleep took even longer to drop off, and also slept for a shorter total time and had less REM sleep. Caffeine didn't affect night time sleep duration or REM. 
+Carrier and her colleagues suggest that the greater daytime effects of caffeine are due to the fact that people are trying to fall asleep at a time when their body clock is telling them to stay awake, even though they are sleep-deprived.
+Slow-wave sleep is known to last longer during daytime, catch-up sleep, they add, which normally helps override this circadian signal.
+Given that caffeine reduces slow-wave sleep, it appears to allow the wake-up call to remain strong.
+
+The site where this hand and forearm stencil was found is 4000-5000 years old
+Fieldwork in what's believed to be one of the most significant rock art sites in Australia has stalled after the federal government declined to fund further research, archaeologists say.
+Over the weekend scientists exploring the Wollemi National Park northwest of Sydney announced the discovery of numerous shelters, many with rock drawings and stencils up to 5000 years old.
+They also discovered what's believed to be the first hafted stone axe found in southeastern Australia, estimated to be around 150 years old.
+But now the archaeologists are being forced to look for international funding to continue their work and can't even afford a day trip to the remote area to protect vulnerable sites from damage by bushfires, says team co-leader Professor Paul Taçon of Griffith University.
+The largest and most significant site, an engraved platform a few kilometres from where the axe was found, is at immediate risk, Taçon says.
+The platform features large eagle and koala figures and images of what are believed to be ancestral beings.
+"There is a lot of vegetation around the edge of the platform and fallen tree limbs which will provide fuel [for bushfires]," he says.
+"If we get a really hot one in the next few months there is a risk that some of the engravings we've discovered won't be there any more.
+"Ideally it would be good to ... just go in to clear it up but at the moment we don't have any funding to do anything at all."
+Taçon says the Australian Research Council informed him last week that his grant application, worth several hundred thousand dollars a year over the next five years, had been knocked back in favour of international projects.
+"The application was for further work in the Wollemi and other parts of the country on rock art," he says.
+"It looks like no rock art projects will be getting up, and hardly any Australian archaeology projects at all. Most of the money went for people working on archaeological projects overseas."
+He says the latest trip and previous surveys of the Wollemi bushland, where the Jurassic-era Wollemi pine was also discovered, have been funded by team members and international organisations.
+The researchers are currently talking to a New Zealand company for funding to help them return for more surveying in April.
+"Given what we've found on each trip there's probably lots more out there," he says. 
+An Australian Research Council spokesperson could not comment on individual funding applications, but confirms some applications for international archaeological projects were successful in the last round.
+"Yes, we did fund a number of archaeological projects ... and several involved research overseas," she says.
+"But it is all by researchers who reside predominantly in Australia."
+The future of the axe
+Meanwhile the future of the axe, which still has traces of resin most likely made from plants and beeswax, remains up in the air.
+Taçon says it will either remain undisturbed in the cave where it was found or be moved to the Australian Museum in Sydney for public display.
+"Perhaps it can remain and eventually turn to dust," he says.
+"Sometimes removing objects destroys the context and connection to the larger landscape and history of a particular area."
+But a final decision about whether the axe should stay or go will be made by local Aboriginal groups, he says.
+Dave Pross, from the Darkinjung Local Aboriginal Land Council, wants to see the axe in a museum to prevent it being picked up by bushwalkers and ending up on an online auction site like many other Aboriginal artefacts.
+ He'll argue for this at the next land council meeting.
+"My view is to get it out and put it into a museum because bushwalkers can come in, find something and put it on eBay," he says.
+"Let's put these things in a museum, as long as they can be used for a display, or showed to students, and they'll be safe."
+
+Horned beetles can have big weapons or big testes, not both
+Beetles with the biggest horns have the smallest testes, say scientists who show that in evolutionary terms you can't have it all.
+They say their finding is clear evidence of an evolutionary trade-off between the ability to fight off sexual competitors and reproductive potency. 
+Or put simply, the ability to find a mate and the ability to fertilise her.
+Professor Leigh Simmons of the University of Western Australia and US researcher Professor Douglas Emlen of the University of Montana publish their findings online today in the Proceedings of the National Academy of Sciences.
+The researchers looked at beetles of the genus Onthophagus, dung beetles known for the size and variety of their horns.
+"What we did was test a fundamental assumption underlying evolution ... that males face a trade-off between competing for access to lots of females and investment in gaining fertilisation with those females," Simmons says.
+"They need to have big horns to win fights and get females and they need to have big testes in order to win in sperm competition.
+"But they can't do both, so species which invest very heavily in their horns tend to invest less in their testes."
+The study also demonstrates the theory of sperm competition, which occurs when females mate with more than one partner, Simmons says.
+According to this theory, male rivalry continues after a mate has been found as sperm from different males compete to fertilise an egg.
+"Theory predicts that males should increase their investment in sperm production as sperm competition in increased," he says.
+Manipulating horns
+Simmons tested the theory by cauterising the area of the developing beetle pupa, where the horns would grow, destroying cells and preventing horn growth.
+He found that if horn development was inhibited, the pupa compensated by developing larger testes.
+The principle is known as a resource allocation trade-off, he says.
+"They got a fixed amount of resources to allocate to various structures, to their legs, their wings, their horns and to their testes and other important organs," he says.
+"If [the developing beetle] doesn't produce horns those males then produce bigger testes because they have resources that weren't used for horn growth."
+Other examples
+Simmons says the principle of resource allocation has been demonstrated in other animal studies.
+For example, there is some evidence that bats trade the size of their testes for brain power.
+And a recent study showed that stalk-eyed flies, in which eye span width is a measure of sexual desirability, trade testes size for the width of their eyes.
+"There have been suggestions of a trade-off between gaining mates and gaining fertilisation but our study is probably one of the most conclusive studies to date to have demonstrated this," Simmons says.
+
+The new element 118 travels through the accelerator to the detector
+Scientists say they have discovered a superheavy element, known as 118, albeit one that has only lasted a fraction of a second over months of experiments.
+Scientists at the Lawrence Livermore National Laboratory in California and Russia's Joint Institute for Nuclear Research in Dubna expect the new element to be a noble gas that lies below radon in the periodic table.
+They publish their results in the journal Physical Review C.
+Scientists discovered the last naturally occurring element on the periodic table in 1925 but have since tried to create new heavier elements. 
+In the latest experiments, the scientists bombarded the element californium with 10^19 calcium ions to create two atoms of element 118.
+The atoms of element 118, also known as ununoctium, lasted 0.9 milliseconds, they say.
+The team then observed the element decay to element 116, then to 114.
+This makes it the fifth new element for the collaborating scientists (113, 114, 115, 116 and now 118).
+An announcement in 2002 from researchers at the Lawrence Berkeley National Laboratory in California claiming they had found element 118 was later shown to have been a fraud. 
+"We selected a completely different nuclear reaction, performed with completely different people in a different laboratory," says Dr Ken Moody, the Livermore team leader.
+"Everything we do is checked and double checked.
+"The data analysis is performed by both us and our Russian colleagues. We do everything that we can possibility do to both avoid the possibility of intentional fraud and of mistaken handling of the data." 
+The Livermore-Dubna team says it's now looking to create element 120, by bombarding plutonium with iron isotopes.
+So it looks like high school and university science labs may still have to replace their periodic table posters yet again.
+
+One day we might be filling our cars with biodiesel produced using genetically modified organisms
+Genetically modified microorganisms could one day make it easier and cheaper to produce biofuels, experts say.
+A symposium convened by the Australian Institute of Agricultural Science and Technology in Canberra this week will hear about future directions in biofuel technology and ways of meeting national biofuel targets.
+Speaker Leo Hyde, research and development manager at DuPont Australia, says improving the yeasts and bacteria that turn raw biomass into fuel is a major step in reducing the use of fossil fuels.
+Hyde says the company is developing bacteria specifically tailored to the production of butanol.
+Like ethanol, butanol can be produced from the sugars contained in cellulose waste from crops like corn or sugar cane, and even logging waste.
+"We have bugs now but they're not efficient enough," he says.
+"What we're working on is another bug that we believe will be far more efficient than the current process [of producing butanol].
+"You'd re-engineer it to make the butanol pathway more efficient. We'll modify pathways, how it uses energy, to improve the yield of the product you want."
+What are the benefits?
+Phillip Calais is a renewable energy consultant and former lecturer in environmental science at Murdoch University, where he's involved in a biofuels project.
+He says there are benefits in using genetically modified or GM bugs in the fermentation of fuels like butanol, which he says is more "oil-like" than ethanol and mixes better with petrol, but is more difficult to produce.
+Butane is made from a raw product that is then broken down to starch or sugars, fermented and purified.
+"With butanol, fermentation has to be very pure. If there are any weird strains of bacteria it really upsets the fermentation process," he says.
+The bugs that are currently used are also destroyed once butanol reaches a certain concentration, which means more costly and time consuming processing is needed to purify it after fermentation.
+"By using GM you can actually breed up different bugs that can survive a higher concentration of purity in the butanol," Calais says.
+"If you can make it more concentrated in the first place by using better bugs you can do less processing later."
+What about the risks?
+The use of GM organisms holds promise for "certain niches", says Adrian Lake founder and president of the Biodiesel Association of Australia.
+But he says the technology is still being developed and has potential risks.
+"There's potential danger in changing any bugs," he says.
+"If it's an organism that's extremely aggressive and has to be highly controlled because it will replicate and damage other organisms, that's a concern."
+
+'Fred the Thread', a caterpillar that lives in the stem of a New Zealand wetland plant
+'Fred the Thread' is vying for a place in the record books as the world's thinnest caterpillar, its discoverers say.
+The New Zealand caterpillar is barely 0.9 millimetres wide and is the larval stage of an entirely new genus and species of moth Houdinia flexilissima.
+But scientists at Landcare Research, who discovered Fred, are concerned about his survival.
+This is because he lives in the cane rush Sporadanthus ferrugineus, a threatened wetland plant that forms peat.
+The researchers publish details of Fred in the latest issue of the journal Invertebrate Systematics.
+Invertebrate ecologist Dr Corinne Watts was researching the restoration of areas mined for peat at Torehape on New Zealand's North Island. And she was intrigued by star-shaped tunnels in the plant stems.
+"It was obvious that something was making them. But every time I cut open a stem there was nothing inside," she says.
+"At the time the caterpillars were so tiny that I kept missing them. It wasn't until they grew bigger that I finally saw a bright orange thread and thought 'gotcha'." 
+Taxonomist Dr Robert Hoare used an electron microscope to measure the caterpillar which, although thin, grows to a respectable few centimetres long. 
+"Sporadanthus stems are very narrow so to live inside them the caterpillar has to get longer rather than fatter," says Watts. 
+Finding the tiny adult moths, only half a centimetre long, proved almost as difficult.
+That was until, using a technique borne of frustration, the scientists learnt that kicking the plants elicited a cloud of them. 
+The moths are active at dusk and survive for a brief breeding period of four to six weeks between October and November.
+Although the entire life cycle is not yet fully understood, it is clear that over two or three years the caterpillar goes through the usual stages of moulting, pupating and metamorphosing into a most unusual moth, all within the confines of a 5 millimetre wide stem.
+Such a feat, as well as the remarkable way the species has managed to elude detection for so long, prompted the new genus to be named after the renowned escapologist Harry Houdini. 
+Fred the Thread's host plant is found in one of three remaining peat bogs on the North Island, the researchers say.
+Over the years, drainage and conversion of peat bogs to pasture has resulted in habitat loss, leading for calls to put the plant on the endangered list and to reappraise the conservation status of the moth.
+
+It could take centuries, not decades, to melt the dense ice packs that accumulate and creep down the Himalayas, says a scientist
+Glaciers in the Himalayas have not drastically shrunk despite climate change and are unlikely to melt away in coming decades, a Chinese scientist says.
+Professor Zhang Wenjing, glacier expert at the Chinese Academy of Sciences, discounted previous forecasts that glaciers across western China could disappear in decades or the Himalayan glaciers could melt away in 50 years, reports the Xinhua news agency.
+"Those predictions may be excessively pessimistic," he says. "So far glaciers in the middle and eastern part of the Himalayas have not shrunk on any large scale."
+Zhang does not question climate change, but says it would take perhaps centuries to melt the dense ice packs that accumulate and creep down the Himalayas.
+"The glaciers in the region are melting comparatively slowly," says Zhang, who is taking part in an international expedition to study the mountains. 
+Zhang's comments appear to clash with the conclusions of many other scientists and conservationists that many parts of the Asian mountain chain are likely to experience severe melting as global temperatures rise in coming decades.
+In the past 40 years, glaciers across the Tibetan plateau that spills from China into South Asia have shrunk by 6600 square kilometres, especially since the 1980s, the conservation group WWF says in a 2005 report.
+The glaciers now cover about 105,000 square kilometres, it says. 
+A report on climate change organised by Chinese government agencies says last year that considerable uncertainty surrounds the effects of rising average temperatures on glaciers in different regions.
+But the report forecast that "by 2050 glaciers in China's west will have dramatically shrunk".
+
+Scientists have fired lasers at cells to make them vibrate, then picked up the characteristic sound of melanoma cells in the blood
+Doctors looking to see if cancer has spread may be able to one day simply listen for it, US researchers report. 
+Researchers at the University of Missouri-Columbia say they have used a technique called photoacoustic detection to pick up the characteristic vibrations of melanoma cells in the blood.
+They say their method could let oncologists spot as few as 10 cancer cells in a blood sample, catching a tumour's spread before it can settle into another organ.
+Writing in the October issue of the journal Optics Letters, the researchers say they combined laser techniques from the field of optics and ultrasound techniques from acoustics.
+They used a laser to make cells vibrate and then picked up the characteristic sound of melanoma cells.
+The researchers say they were able to detect melanoma cells obtained from actual patients.
+The dark, microscopic granules of melanin in the melanoma cancer cells absorb the energy bursts from the blue laser light.
+As the melanoma cells expand and contract, they generate crackling sounds that can be picked them up with special microphones and analysed by computer. 
+Other human cells do not contain pigments with the same colour as melanin, so the melanin signature is easy to tell apart from other noises, says Assistant Professor John Viator, a biomedical engineer who worked on the study. 
+"The only reason there could be melanin in the human blood is that there would be melanoma cells," he says. 
+A blood screening test could reassure patients who have a growth removed, or tell a doctor to start chemotherapy quickly because the cancer has already started to spread. 
+"It could take just 30 minutes to find out if there are any circulating cancer cells," Viator says. 
+Because of melanin, melanoma is the only type of cancer that can be detected in this way.
+But the researchers say they could try using artificial materials to act as light absorbers and as noise makers.
+"We're looking for methods to attach other kinds of absorbers to cancer cells," Viator says.
+
+The fish skull emerging from the rock it was found in
+Fish developed features characteristic of land animals much earlier than once thought, say researchers.
+Dr John Long of Museum Victoria and colleagues base their conclusions on an uncrushed 380 million-year-old fish fossil found in Western Australia.
+"The specimen is the most perfect complete three-dimensional fish of its kind ever discovered in the whole world," says Long, who reports the team's findings online today in the journal Nature.
+"It looks like it died yesterday. You can still open and close the mouth."
+Long says the preserved remains of a Gogonasus fish from the Devonian period were found last year in the remote Kimberley area at the Gogo fossil site, once an 'ancient barrier reef' teeming with fish.
+Previous analyses based on limited material suggested Gogonasus had relatively primitive features, says Long.
+But when his team used a CT scanner at the Australian National University to analyse this new fossil, it found the fish had a number of features common to land animals.
+"It's hiding a lot of deceptively advanced features that were not recognised before until we had such a perfect specimen," says Long.
+For example, Gogonasus had hole in its skull similar to that found in the first land animals, he says.
+This hole eventually became the Eustachian tube in higher vertebrates, says Long.
+His team's analysis also revealed the fish's pectoral fin had the same pattern of bones as the forelimbs or arms of land animals, called tetrapods.
+"It's definitely a fish. It's got gills, it swims in water, it's got fins," says Long. "But it's a fish that is showing the beginnings of the tetrapod's advanced body plan that would eventually carry on to all living land animals."
+Gogonasus also had a cheek bone structure similar to early amphibian and a single pair of nostrils, like we have, says Long.
+Wolf in sheep's clothing
+Earlier this year scientists reported the discovery of Tiktaalik roseae, a 375 million-year-old species of fish that filled the evolutionary gap in the transition between water and land animals.
+While Tiktaalik had a skull that was identical to an amphibian, Gogonasus looks much more like a fish, says Long.
+"This particular fish is a bit like a wolf in sheep's clothing," he says.
+
+This image of the lunar south pole, together with radar echoes, was thought to be evidence for ice. Now scientists say it isn't ice, just rough terrain
+Hopes that the Moon's south pole has a vast hoard of ice that could be used to establish a lunar colony are sadly unfounded, a new study says. 
+In 1994, radar echoes sent back in an experiment involving a US orbiter called Clementine appeared to show a treasure trove of frozen water below craters near the lunar south pole.
+At the time, scientists saw this as evidence of ice in areas that were permanently shaded from the Sun.
+If so, such a find would be an invaluable boost to colonisation, as the ice could be used to provide water as well as hydrogen as fuel.
+NASA is looking closely at the south pole as a potential site for the US return mission to the Moon, scheduled to take place by 2020.
+But a paper published today in the journal Nature says the Clementine data was most probably misinterpreted.
+Professor Donald Campbell of Cornell University and colleagues, including Dr Nicholas Stacy from Australia's Defence Science and Technology Organisation, collected radar images of the Moon's south pole to a resolution of 20 metres.
+They looked especially at Shackleton crater, which had generated most interest.
+The team found that a particular radar signature called the circular polarisation ratio, which in the Clementine experiment was taken to indicate thick deposits of ice, could also be created by echoes from the rough terrain and walls of impact craters. 
+The signature was found in both sunny and permanently shady areas of crater, which suggests that the reflection comes from rocky debris, not thick ice deposits.
+If there is any ice at the south pole, it probably comes from tiny, scattered grains that probably account for only 1-2% of the local dust, the authors suggest.
+"Any planning for future exploitation of hydrogen at the Moon's south pole should be constrained by this low average abundance rather than by the expectation of localised deposits at higher concentrations," the paper says.
+The research involved sending a radar signal from the Arecibo telescope in Puerto Rico.
+The signal hit the southern lunar region and the reflection was picked up by the US Green Bank Telescope.
+
+The latest study on the best time of year to shear sheep overturns 20 years of thinking
+Farmers who want to produce better quality wool don't necessarily need to shear their sheep in autumn, Australian researchers have found.
+Angus Campbell, a PhD student from the University of Melbourne, and colleagues show that there's no particular shearing season that consistently improves wool strength.
+That finding could have important implications for Australia's multi-billion dollar wool industry.
+For the past 20 years or so, many farmers have sheared their sheep in autumn in the hope of getting better quality fibres and a higher price for their wool.
+"The idea behind this is that wool gets thinner in summer and then thickens in late autumn," Campbell says.
+This would make the wool stronger because it would be thin on the end but thicker and stronger in the middle.
+To test this theory, Campbell and his colleagues designed a study that used real life conditions on two commercial Merino farms west of Geelong in Victoria.
+Each year for five years, they sheared 1000 ewes and lambs in three different seasons and measured the quality of the wool.
+One-third of the sheep were shorn in December, one-third in March and another third in May.
+"These were three realistic shearing times based on other research and talking to wool growers," he says.
+The result? "The wool strength from those three shearing times was the same," Campbell says.
+The connection between wool fibre thickness and season has more to do with nutrition than weather, the researcher explains.
+In summer the fibres tend to get thinner as the flocks rely more on dried feed, while the rains of autumn bring protein-rich green grass, which makes the wool quickly get thicker.
+But in spring, when many farmers have their sheep bearing lambs, a similar thing happens because the ewes devote all their energy into growing the lamb, and not into the wool.
+"This all means that among ewes and lambs no annual shearing time is going to consistently shear through the weak part of the fibre," Campbell says.
+In a way, the results are good news for farmers, he says.
+"It means that if a farmer has a really good reason for choosing a shearing time based on something specific to the farm, then I reckon they can go ahead and do it and not worry about it harming their wool value," he says.
+Campbell's research will form part of his PhD, which is to be submitted later this year.
+
+It's how you see things. Throughout the ages, scientists have been quick to judge scientists whose work doesn't fit their view of the world
+Scientists may say they are dispassionate defenders of the unfettered pursuit of truth. But history suggests they are often guilty of being irrational and narrow-minded, says an Australian philosopher.
+Emeritus Professor Miles Little of the University of Sydney argues his case in the current issue of the journal Medical Humanities.
+"Science is supposed to be the ultimate in rationality. It's supposed to be the ultimate in evidence and the assessment of evidence," says Little, a former surgeon now at the university's Centre for Values, Ethics and the Law in Medicine.
+"But science doesn't behave like this in the face of aberrant science."
+Aberrant science can involve the use of methods or the arrival at conclusions the majority don't agree with and is often shunned as if it was fraudulent, he says.
+And yet, says Little, some aberrant science is by honest hardworking scientists who produce very important results.
+While fraud is clearly an undesirable form of aberrant science, Little says those whose only crime is to use unusual methods or reach unusual conclusions should not be treated with the same contempt.
+Instead, he says, they should be greeted with open-mindedness, a feature that is supposed to be the hallmark of good science.
+Little says an example of such unfairly treated aberrant science is something that challenges the current scientific paradigm, the given set of assumptions about how the world works.
+An example of this is the claim, made by immunologist Dr Jacques Benveniste in the late 1980s.
+He said a solution of antibodies so dilute they were unlikely to contain any molecules could activate white blood cells, a claim could be used to support the claims of homoeopathy.
+Little says the scientific community's immediate response to what they saw as "dysfunctional science" was to attack Benveniste personally and to vilify and humiliate him.
+"The way the judgement was made was not scientific," says Little.
+While subsequent attempts failed to reproduce Benveniste's results, Little says the outcome of other cases of aberrant science have been eventually accepted. 
+One example is Professor Joseph Lister who argued against the wisdom of the 19th century that pus was a sign of infection by germs, which should be prevented from entering wounds.
+"The majority of surgeons rejected it out of hand," says Little.
+Lister was seen as a "young whippersnapper, defying well-established tradition, flying in the face of authority" and it took the next generation of surgeons to accept his views.
+Little says a related category of unfairly treated aberrant science is something that challenges the accepted ideology of the day. 
+
+Scientists have made an invisibility cloak that works with microwaves. But there are many technical challenges before a cloak could work with visible light to make someone invisible
+Scientists say they have found a way to hide an object from microwave radiation in a first step towards making what they hope will be an invisibility cloak.
+The cloaking device is said to deflect microwaves so they flow around a 'hidden' object inside it with little distortion, making it seem as if there was almost nothing there.
+Such a device could one day be used to elude radar or in wireless communications.
+But the researchers, like many scientists, are not working with any particular goal in mind but hope its uses will become apparent later.
+"It's not quite Harry Potter," says Professor David Smith of Duke University in North Carolina, referring to the child's fictional character who can conceal himself in a magical cloak. 
+"It's not exactly perfect; we can do better. But it demonstrates the mechanism, the way the waves swirl around the centre region where you want to conceal things," says Smith, who publishes the results online today in the journal Science.
+Building a cloak
+Every solid object scatters radiation that hits it, from microwaves through to visible light. It is this scattering that allows objects to be seen, whether with the eye or using radar or ultrasound. 
+The cloaking device manipulates this scattering effect.
+It relies on new, laboratory-made materials called metamaterials, engineered composite materials whose properties can be manipulated by tweaking their structure.
+For instance, metamaterials can decrease both the scattering caused by a solid object and the shadow it casts. 
+In this case the cloak is quite thick, Smith says, twice as big as the 15 centimetre copper tube it hides. And the materials are arranged in concentric rings.
+In May the same researchers reported their theory, and it took them just a few months to demonstrate it.
+The cloak reduces both back scatter, or reflection of microwaves, and forward scatter, or shadows. 
+Limitations
+The cloak only works in 2D. But the researchers have already started work on a 3D version.
+The cloak also only works with microwaves of a specific wavelength. And the researchers hope to broaden the range of wavelengths that it can block.
+But making something invisible to the human eye would present a much greater challenge.
+Such a cloak would have to simultaneously interact with all the wavelengths that make up light.
+"It is very unlikely that we could do it with this technology in the visible [spectrum]," Smith says.
+It would have to be scaled down to nanotechnology levels, but the metals involved behave differently on that scale, he says. 
+Eluding radar
+Microwave cloaks might be useful for eluding radar, says Professor Costas Soukoulis, a theorist with the US Department of Energy's Ames Laboratory in Iowa.
+"This is very, very important that experiments have produced what theorists had predicted," Soukoulis told Science.
+The researchers are funded by the Defense Advanced Research Projects Agency and the design is based on a theory proposed by Professor John Pendry of Imperial College London.
+
+Brain damage can improve your artistic skills but can also make your paintings less 'emotional'. So does everyone have the potential to become the next Picasso?
+Damage to a particular part of the brain can trigger artistic talent, US neurologists show.
+When they looked at one particular artist whose frontal and temporal lobes of the brain had deteriorated, they found she had developed new artistic skills. 
+The US researchers published their study into the artistic effects of frontotemporal lobar dementia in the latest issue of the journal Neurology.
+There have been reports of previously inartistic people becoming talented visual artists after developing this condition.
+But it is not clear whether the brain atrophy is releasing dormant talent, or the disease itself has somehow triggered the artistic expression. 
+To investigate, Dr Valeria Drago of the University of Florida at Gainesville and others studied the art of a woman who had been an artist before developing this type of brain damage.
+As the woman's condition worsened, they found, her artistic technique improved, but the emotional power of her work decreased.
+"We can really follow how the paintings have been changed following the disease," says Drago. 
+Drago and her team gathered 40 of the woman's paintings, including several from the period before she developed symptoms. Some were when her symptoms were beginning, and some were painted later. 
+The researchers then gave 18 men and women training on how to evaluate six different artistic qualities, and asked them to rate the paintings.
+Ratings for the paintings' artistic skill rose as the woman's disease progressed.
+But ratings on the paintings' 'evocative impact' and 'closure' fell. 
+Evocative impact is the ability of a work of art to elicit an emotional reaction, while closure is the sense that a painting is finished and complete. 
+Drago and her team note that the condition leaves the parts of the brain at work in drawing, painting and other skills relatively intact.
+The part of the brain the disease does affect may typically inhibit this region of the brain, so when it is damaged artistic talents have freer rein, they suggest. 
+The researchers also point out that patients with this form of brain damage may have damage to the limbic system, a network within the brain essential for mediating emotions.
+This damage could in turn impair an artist's ability to paint emotionally affecting paintings, or to portray emotion visually. 
+Drago says she and her team are continuing to study creativity and the brain, and are currently looking at how normal ageing may change creativity.
+
+Women who believe that men are better at maths do worse in maths tests than women who don't believe the stereotype
+When women believe they are genetically bad at maths, the belief becomes a self-fulfilling prophesy, research shows.
+The divide between men's and women's talent at maths may therefore be due to misinformation more than genetic destiny.
+A report published in the latest issue of the journal Science shows that women exposed to theories saying females are genetically bad at maths perform far worse on maths tests than women who had not been exposed to such beliefs. 
+Canadian psychologists Associate Professor Steven Heine and doctoral student Ilan Dar-Nimrod, from the University of British Columbia, studied how 220 female students performed in maths tests after reading fake research reports.
+The psychologists had invented the reports, which contained bogus claims about men being better at maths.
+One phoney paper claimed to have discovered that the male Y chromosome gives men a 5% edge over women in maths.
+Another fake paper claimed that men have a 5% edge because maths teachers stereotype girl and boy students at a very young age.
+Heine says the research clearly shows that women who read the fake report about genetics did much worse in the maths test. 
+The research, he says, shows that people believe they can overcome stereotyping and continue to try.
+But if they blame their genetic makeup and believe they have an innate lack of ability, they give up, he says.
+"People think genes are at the core of who we are," he says. "But much genetics research is still unproved. Just raising the question about genes has harmful consequences."
+Often, says Heine, science about research on genes affecting gender, obesity or homosexuality is "grossly simplified" in the media. 
+"The reports themselves have the potential to undermine people's motivations. If I believe that genes have a deterministic influence on my weight, will I still struggle to keep up with my diet and exercise routine?
+"Genetics research is a booming industry, and every week [scientists] are identifying a new gene," he says.
+But genes work in complicated ways scientists don't yet understand, he warns, and "not all scientific theories are created equal".
+So-called 'brain sex', genetic differences between men's and women's brains, is a controversial research subject. 
+It's so contentious that earlier this year Professor Lawrence Summers resigned as president of Harvard University amid an uproar after he suggested that women have less intrinsic ability in maths and science than men.
+
+Champion racehorse Phar Lap died more than 70 years ago. But a scientific test has sparked fresh debate about what caused his demise (Melbourne Museum)
+Claims that champion Australian racehorse Phar Lap was killed by arsenic poisoning are premature, says an expert who has cast doubt on reports today that science has solved one of the nation's biggest sporting mysteries.
+Professor Rob Lewis, director of the Monash University Centre for Synchrotron Science, says there are too many "ifs, whats and wherefores" to declare the case of Phar Lap's unexplained death shut.
+Lewis, who has seen the results of synchrotron analysis of Phar Lap's hair conducted in the US, says the research is preliminary.
+He says it's too early to tell whether arsenic detected in the hair is from a chemical used during the taxidermy process to preserve the horse, or the results of foul play.
+Phar Lap, the 1930 Melbourne Cup champion and one of Australia's greatest sporting icons, died in 1932, shortly after winning America's richest race the Agua Caliente Handicap.
+The exact cause of his death has never been proved although there was speculation it was the work of gangsters.
+So Dr Ivan Kempson, a research fellow based at the University of South Australia, came up with the idea of using a synchrotron to analyse Phar Lap's hair.
+"All of our analysis so far indicates that he most probably did consume a dose of arsenic just prior to his death," he says.
+Kempson says analysis by the Advanced Photon Source synchrotron near Chicago shows two forms of arsenic. 
+One of them, lead arsenide, could be associated with preservation, he says. But the other is more likely to be the result of ingestion.
+"The other type of arsenic is consistent by its distribution and location and chemistry with him ingesting the arsenic between 30-40 hours prior to his death," he says.
+"We've been going through a process of trying to prove ourselves wrong and look for alternative explanations but so far the results are consistent with him consuming arsenic." 
+Horse hair samples
+But Lewis says more work is needed to analyse samples from the stuffed horse, which is preserved for public display at the Melbourne Museum.
+"Nobody's ever actually analysed hair from an animal that's been stuffed for this long," he says.
+"What you really need to prove this kind of thing is 20 horses that were stuffed, and you check all of them and if you find a major problem in one of them you say that one's different. But in this case we've got one.
+"And given that we don't actually understand exactly what procedure was used to preserve Phar Lap, how do we know whether the stuff was used in the preserving or whether it was given to him beforehand?"
+Lewis says synchrotrons can closely analyse the structure of chemicals like arsenic.
+"The synchrotron without any shadow of a doubt gives you more information than you could have got in other ways. But whether or not it's conclusive, would it stand up in a court of law, personally I have my doubts," he says.
+"There are all sorts of things we don't quite know, we don't know the process that was used in tanning the hide, [we don't know] what has happened to the condition of that arsenic in the years since Phar Lap died. 
+"Things oxidise, things change, bugs get in, all sorts of things change. Biological materials don't stay the same and clearly that sort of thing might have happened."
+Kempson says more research is planned to hopefully finally lay the case to rest, including comparison with similar cases.
+So far, Phar Lap's sample has only been compared with a stuffed monkey, he says. 
+What is a synchrotron?
+Lewis describes a synchrotron, or particle accelerator, as essentially a large x-ray machine that can concentrate a large number of x-rays onto a tiny object like a single hair.
+The x-rays are produced by particles that are accelerated around a large ring at close to the speed of light. As the particles pass magnetic fields in the ring they emit rays approximately a billion times brighter than the Sun.
+"In this case instead of looking at the x-rays that go straight through the hair ... you look at the x-rays that scatter off it and come off in different directions," he says.
+"Those x-rays carry information about things like the arsenic and the chemistry of the arsenic."
+
+No single event, like a huge meteor strike, is solely responsible for a mass extinction, says new research. Not even the demise of the dinosaurs 65 million years ago
+If you can't decide if you prefer meteor impacts, volcanoes or some other explanation for Earth's biggest mass extinction events, take heart: you no longer have to choose.
+A new statistical study of mass extinctions throughout the history of life on Earth is backing the idea that no single meteor, volcanic eruption or other lone gunman is ever to blame.
+This even applies to the Cretaceous-Tertiary event that brought the end of dinosaurs 65 million years ago, the US researchers say.
+Instead, the worst die-offs happen when some sort of interminable, multi-generational pressure on life is combined with a few powerful blows.
+It's what is now being called the press-pulse theory of mass extinctions. 
+Reading the Cretaceous-Tertiary extinction literature and conversations with colleagues "made me wonder whether the simplistic scenario of 'everything's fine until one day in June when the asteroid hits and everything goes to hell-in-a-hand-basket' really explains the diversity of data," says plant fossil expert Associate Professor Nan Arens of Hobart and William Smith Colleges in New York. 
+Wouldn't it make more sense, she surmised, if certain species were already vulnerable when the triggering event happened?
+To test the idea, she and then-undergraduate student Ian West compiled a large database of marine organisms and their extinctions through geological time. 
+They divvied up the past 488 million years into four groups: suspected meteor impacts (pulses), gigantic volcanic flood basalt eruptions (presses), periods with neither presses nor pulses, and times when press and pulse coincided.
+They then compared average extinction rates in each group. 
+Flood basalt eruptions are considered presses because they release vast amounts of greenhouse gases into the atmosphere and can change the Earth's climate. 
+Single or multiple event?
+The researchers found similar extinction rates when a pulse or press occurred by itself, and when neither was occurring, says Arens.
+"However, when an impact occurred during a time of volcanic flood, that produced higher extinction rates."
+Arens is presenting her work this week at the annual meeting of the Geological Society of America in Philadelphia.
+"The goal of our work was to come up with a unifying theory of mass extinctions," says West.
+They also wanted to make the theory applicable to the rapid extinctions now being seen as a result of accelerating climate change (press) and the ongoing destruction of wild habitats by human activities worldwide (pulse).
+"[The theory] is essentially a more eloquent way of saying what I and many other palaeontologists have been saying for many years," says Professor Gerta Keller of Princeton University.
+"Namely that the impact-kill hypothesis is all wrong. Impacts alone could not have been the killing mechanism for the K-T [Cretaceous-Tertiary event] or any of the other major mass extinctions." 
+Volcanic activity
+In the late Cretaceous case massive volcanism, the Deccan Traps eruption in India, and attendant climate change, coincided with an impact that pushed highly stressed biota over the brink. 
+"I'm very happy they have done the analysis based on the literature and come up with the same conclusions that palaeontologists have been preaching all along," Keller says.
+
+Viruses may be able to cross into the brain, causing steady damage over the years
+Forget where you left your glasses? Did those keys go missing again? A virus may be to blame.
+Viruses that cause a range of ills from the common cold to polio may be able to infect the brain and cause steady damage, a team at the Mayo Clinic in Minnesota reports.
+"Our study suggests that virus-induced memory loss could accumulate over the lifetime of an individual and eventually lead to clinical cognitive memory deficits," says Dr Charles Howe, who reports the findings in the latest issue of the journal Neurobiology of Disease. 
+The viruses are called picornaviruses and infect more than 1 billion people worldwide each year. 
+They include the virus that causes polio, as well as colds and diarrhoea. People contract an average of two or three such infections a year. 
+"We think picornavirus family members cross into the brain and cause a variety of brain injuries. For example, the polio virus can cause paralysis," Howe says. 
+"It can injure the spinal cord and different parts of the brain responsible for motor function. In the [mouse] virus we studied, it did the same thing and also injured parts of the brain responsible for memory." 
+The researchers infected mice with a virus called Theiler's murine encephalomyelitis virus, which is similar to human poliovirus.
+Infected mice later had difficulty learning to navigate a maze. Some were barely affected, while others were completely unable to manage.
+When the mice were killed and their brains examined, a correlating amount of damage was seen in the hippocampus region, related to learning and memory.
+One virus particularly likely to cause brain damage is enterovirus 71, which is common in Asia, the researchers say.
+It can cross over into the brain and cause encephalitis, a brain inflammation that can lead to coma and death. 
+"Our findings suggest that picornavirus infections throughout the lifetime of an individual may chip away at the cognitive reserve, increasing the likelihood of detectable cognitive impairment as the individual ages," the researchers write.
+"We hypothesise that mild memory and cognitive impairments of unknown aetiology may, in fact, be due to accumulative loss of hippocampus function caused by repeated infection with common and widespread neurovirulent picornaviruses."
+Other viruses kill brain cells, including the herpes virus and HIV.
+
+This mock-up illustrates the dangers foxes pose to penguins on Phillip Island
+A drug that makes vixens neglect their cubs could help solve Australia's feral fox problem, researchers say.
+They are looking at the drug cabergoline, which reduces fertility and interferes with maternal instincts, to see if it could control foxes on Phillip Island in Victoria.
+The island is home to a renowned penguin colony and up to 150 unwanted foxes.
+A fox can kill up to 30 penguins a night, says Dr Roger Kirkwood, a biologist at the Phillip Island Nature Park.
+"We need to eradicate foxes from the island because just one fox can step in there and do so much damage," he says.
+The foxes also feast on migratory mutton birds that visit the island, says Kirkwood.
+He's working with University of Tasmania pharmacologist Professor Stuart McLean to study cabergoline.
+In humans, the drug is used to treat Parkinson's disease.
+But the scientists are interested in using the drug in foxes as it acts on the brain's dopamine receptors to block secretion of the hormone prolactin.
+"[Foxes] rely on prolactin to become pregnant and maintain pregnancy and to lactate, and also for their mothering instinct after the cubs are born," says McLean. 
+Because it suppresses maternal instincts, cabergoline makes vixens less likely to care for their cubs by bringing them food, grooming them and teaching them survival skills, which reduces their chances of survival.
+The drug has not yet been tested on foxes on the island but preliminary research will be presented at the Australian Health and Medical Research Congress next month.
+A study looking at how long cabergoline remains in fox bait has also been submitted to the journal Wildlife Research.
+Toll on penguins
+Kirkwood says if foxes are allowed to breed out of control they could destroy Phillip Island's 60,000 strong penguin population.
+Foxes have already reduced the number of penguin colonies on Phillip Island from 12 to just one in the past 80 years.
+More than 1000 foxes have been eliminated since the introduction of a control program on the island in 1980, which includes shooting, poisoning, fumigating dens and using dogs to hunt the foxes.
+Kirkwood says although foxes only live about five years the population is resilient and recovers quickly.
+"If we stopped our program we reckon the carrying capacity of the island would be over 400 foxes, and they would eliminate the penguins given time if we didn't control them," he says.
+
+Are you a YouTube legend? Be careful your videos don't get you into legal hot water
+Internet law experts have called for Australian copyright laws to be amended so people can post online videos of themselves miming pop songs without risking prosecution.
+Researcher Damien O'Brien and Professor Brian Fitzgerald of Queensland University of Technology (QUT) say miming copyright material and posting it online may be currently illegal.
+They will explore copyright law in relation to the popular YouTube site in the Internet Law Bulletin.
+The video sharing website YouTube hosts more than 65,000 new videos every day, many made by amateurs.
+"A 12 year old girl uploads a video of herself lip-syncing the latest Shakira pop song onto YouTube and is served with a copyright infringement notice," they write.
+"Has she breached copyright law?" The answer, they say, is yes. 
+"Certainly many of the videos that are uploaded [onto YouTube] probably infringe copyright if they're reproductions or communications of the whole, or even a little bit of the [original]."
+O'Brien says while there have been no prosecutions in Australia yet, major music companies, particularly in the US, have been active in demanding that such videos be removed from YouTube.
+Calls for change
+He says amendments to Australian copyright law currently being considered by parliament fail to take cases like amateur miming into account.
+O'Brien says some types of reproduction are allowed under fair trading provisions in the amendments, but these don't cover cases like the one highlighted in his paper.
+He's arguing for a defence of material being "highly transformative" and not competing with the original market. 
+This would allow a 12 year old amateur to upload a video of herself miming to a sound track with impunity.
+"It doesn't have to be a radical change [to the amendments], but something that allows someone to remix a  small amount of someone else's work and put it in a different context as long as it's not for commercial purposes and doesn't compete with the original," he says.
+"It's pretty hard to see why something like that shouldn't be allowed."
+New laws
+The federal government last week introduced its proposed changes to copyright law into parliament.
+Announcing the move, attorney general Philip Ruddock said the bill demonstrated "the government's commitment to ensuring laws reflect the continual changes to the technical landscape".
+A spokesperson says following concerns about the bill, debate has been adjourned while a senate committee gives the legislation further consideration.
+"The purpose of draft exposure bills is to circulate them for comment and expose any potential flaws before the legislation is introduced to parliament," the spokesperson says.
+O'Brien's paper is also on the QUT ePrints website.
+
+Scientists study Rio Tinto in Spain to learn more about Mars. The river has an extreme acidic pH and a high concentration of heavy metals, yet  microbes grow there. So could the harsh conditions on Mars also harbour life?
+The US space agency's first experiments to look for organic matter on Mars may not have been sensitive enough to detect life, concludes a team of researchers studying Martian-like soils in remote regions on Earth.
+The twin NASA Viking probes landed on the surface of Mars in 1976 to search for signs of past or present life.
+One test involved rapidly heating soil samples so they vapourised, leaving trace molecules to be analysed by spectrometers. 
+No biological materials were found and NASA abandoned ground exploration of Mars for more than 20 years.
+But Dr Rafael Navarro-Gonz&aacute;lez, a researcher with the National Autonomous University of Mexico, and colleagues have another explanation for the Viking results.
+Writing in the latest issue of the Proceedings of the National Academy of Sciences, they say the experiment could have missed low levels of biological activity.
+The researchers built their theory on studies conducted with Viking-type instruments in some of Earth's harshest environments: the Antarctic Dry Valleys, the Atacama Desert of Chile and Peru, and deserts in Libya. 
+Soil samples in those locations contain trace amounts of materials that Viking would have missed.
+Despite inhospitable conditions, soil samples from many of the team's test sites showed signs of life.
+In 2004, the Mars rover Opportunity discovered an iron-rich mineral called jarosite on the surface of Mars, points out Navarro-Gonz&aacute;lez. The same mineral is known to exist in Spain's river Rio Tinto.
+"So I decided to collect sediments from this river, which has a very acidic pH ... high levels of iron and yet the presence of microorganisms from the three domains of life," he says.
+The team also discovered that iron-rich soils could oxidise organic molecules into carbon dioxide, further reducing the amount of material left behind. 
+This finding also might explain the high levels of carbon dioxide the Viking instruments measured in the Martian soil, say the researchers.
+"The Martian surface could have several orders of magnitude more organics than the stated Viking detection limit," the authors write.
+While most scientists believed Viking's findings to be clear-cut, others were not convinced.
+Dr Gilbert Levin, one of the mission's lead scientists, has long maintained that his life-detection experiment found living microorganisms in the soil of Mars.
+Researchers now also believe that the best place to look for signs of life is underground, which is more protected from solar radiation.
+NASA's current approach to Mars exploration is to look for signs of past and present-day water, which is believed to be necessary to support life. 
+Over the past 10 years, NASA has dispatched a series of increasingly sophisticated probes to Mars to survey minerals and geological formations from above the planet's surface, and to analyse soil and rock chemistry with rovers on the ground.
+"We suggest that the design of future organic instruments for Mars should include other methods to be able to detect extinct and/or extant life," the authors conclude.
+NASA's next two landers, the 2007 Phoenix mission and the 2009 Mars Science Laboratory, both include instruments to analyse soil samples for water, carbon dioxide and organic materials.
+Europe's ExoMars mission, slated for launch in 2011 or 2013, is designed to characterise the biological environment on Mars.
+
+Cloning a mammoth was one of Professor Hwang Woo-suk's sideline projects. But who do you call when you need tissue samples?
+Disgraced South Korean stem cell scientist Professor Hwang Woo-suk says he spent private donations for research to pay the Russian mafia for mammoth tissues to clone extinct species.
+Hwang, once celebrated as a national hero, was indicted in May on charges of fraud and embezzlement after prosecutors said he was the mastermind of a scheme to make it look like his team had produced stem cells through cloning human embryos. 
+He previously told a Seoul court that he spent part of more than US$1 million in corporate donations for "peripheral activities related to research". 
+"Some of the money was spent in contacting the Russia mafia as we tried to clone mammoths," Hwang told the court during a hearing this week.
+"But you can't say that [on the expense claim] so we expensed it as money for cows for experiment."
+Hwang previously said he obtained mammoth tissues from glaciers and tried to clone them three times but failed. 
+Prosecutors have charged Hwang with fraud to secure funds and misusing US$2.9 million in state funds and private donations as well as violating bioethics laws in procuring human eggs for research. 
+An investigation panel at Seoul National University, where Hwang once worked, said his team fabricated key data in the two papers on embryonic stem cells that were once heralded. 
+Misuse of state funds carries a penalty of up to 10 years in jail, while violating the bioethics laws can lead to three years' imprisonment, prosecutors say.
+Hwang denied any of the funds were used for anything other than research. He described extra expenses incurred when trying to secure animal ovaries in addition to paying for junior researchers' housing and travel. 
+"Do you know how hard it is to secure four or five animal ovaries at butcher shops? You need to keep the workers there happy," he says.
+
+Surgeons may perform a full face transplant within months
+The world's first full face transplant, which was authorised by a UK medical watchdog this week, is hedged with technical, psychological and ethical challenges, experts say. 
+The green light given to surgeon Mr Peter Butler by the ethics committee at London's Royal Free Hospital opens the way to an operation that could take place within months.
+But the decision was reached cautiously, reflecting an agonising debate about safety.
+These fears were only eased after French doctors last November carried out the first partial face transplant and in July pronounced it a success. 
+These are the main challenges from a full facial graft, say experts: 
+Surgery
+Nerves and the main vessels that carry blood to the face are connected by surgery under a microscope. 
+This task is common in reconstructive surgery and has a high success rate. Of the 24 hand transplants that have been carried out on 18 people over the past eight years, only two have failed. 
+But microsurgery also carries a 5-10% risk of transplant failure from clots that may form within the connected blood vessels in the first few days after surgery.
+Immunosupressors
+These powerful drugs inhibit the immune system so that the transplanted tissue is not attacked by the body's defences. But they also make the body more vulnerable to infection and disease. 
+In addition, heavy use of immunosuppressors boosts the risk of cancer. The danger of life-threatening diseases poses an ethical problem because before the transplant, the recipient was generally healthy. 
+To counter the immunosuppressor problem, doctors may give the graft recipient tiny doses of material from the donor so that his or her immune system becomes accustomed to the tissue and therefore stops attacking it. 
+The technique is still experimental but has had promising results with kidney transplant patients.
+Doctors who performed the partial face transplant on Isabelle Dinoire, 38, last November also gave her a bone marrow graft from the donor. 
+Psychological
+Selecting the patient with the right profile is one of the hardest tasks of all. 
+The face is the mark of one's identity, so wearing someone else's face, or seeing someone else with the face of a deceased relative, for instance, may be deeply disturbing for some.
+But the operation is new, which means no-one really knows for sure how it will work. 
+On the positive side, computer modelling suggests facial tissue looks quite different and may be even unidentifiable when attached to someone else because the underlying bones and muscles fill it out differently. 
+"Every graft of a visible organ leads to an identity split, the consequences of which can be very serious if the recipient does not succeed in psychologically accepting the organ and in rebuilding its social expression in everyday life," French experts wrote in The Lancet in July.
+The right candidate is therefore someone who is robust and does not entertain the belief that the operation will miraculously restore their former lives, a hope that fades to bitterness and alienation when complications inevitably occur. 
+Seen as 'alien'
+In the case of the world's first hand transplant, recipient Clint Hallam begged to have the new limb cut off because he viewed it as alien. 
+"Thorough psychological preparation is vital to the successful selection of patients," says The Face Trust, a charity set up to fund research for surgical reconstruction and face transplants.
+"The challenge we face is that the people who cope least well with facial injury may also be the [people who] cope least well with facial transplantation  and its long-term impact on lifestyle."
+
+Sequencing the honey bee genome could improve the search for genes linked to social behaviour
+Scientists have unravelled the genetic code of the honey bee, uncovering clues about its complex social behaviour, heightened sense of smell and African origins. 
+The results, published in the journal Nature, makes the bee the third insect to have its genome mapped and joins the fruit fly and mosquito in the exclusive club. 
+The honey bee, or Apis mellifera, evolved more slowly than the other insects but has more genes related to smell. 
+"In biology and biomedicine, honey bees are used to study many diverse areas, including allergic disease, development, gerontology, neuroscience, social behaviour and venom toxicology," says Professor Gene Robinson, director of the University of Illinois and one of the leaders of the project.
+"The honey bee genome project is ushering in a bright era of bee research for the benefit of agriculture, biological research and human health," he adds. 
+With its highly evolved social structure of tens of thousands of worker bees commanded by the queen, the honey bee genome could also improve the search for genes linked to social behaviour. 
+But the consortium of scientists, which includes Australians, says a comprehensive analysis of the honey bee and other species will be needed to understand its social life.
+The queen lives 10 times as long as workers and lays up to 2000 eggs a day. Despite having tiny brains, honey bees display honed cognitive abilities and learn to associate a flower's colour, shape and scent with food, which increases its foraging ability. 
+The scientists who analysed the genetic code have discovered the honey bee originated in Africa and spread to Europe in two ancient migrations. 
+"The African bees' spread throughout the New World is a spectacular example of biological invasion," the scientists write. 
+The number of genes in honey bees related to smell outnumber those linked to taste. The insects also have fewer genes than the fruit fly or mosquito for immunity. 
+Honey bees use pheromones, substances secreted by glands, to distinguish the gender, caste and age of other bees, according to the scientists. 
+"This DNA sequence is a major step towards answering a basic question of social evolution. At the genomic level, what does it take to engineer an advanced colonial insect?" says Professor Edward Wilson, of Harvard University in a commentary on the research.
+
+Researchers say their system of injecting ethanol into the engine saves petrol and costs consumers less than a hybrid car
+Injecting small quantities of ethanol into car engines at moments of peak demand could improve fuel economy, US scientists say.
+Researchers at the Massachusetts Institute of Technology (MIT) say a little squirt into the engine when the car is accelerating sharply or climbing a steep hill could improve fuel economy by 20-30%.
+The researchers say such as system would allow carmakers to use smaller engines in their vehicles.
+They say this would reduce weight and improve fuel economy at a lower cost to consumers than by adding a hybrid engine.
+"To have a big impact on reducing oil consumption, one needs a low-cost way of improving efficiency, so a lot of people buy the car," says Dr Daniel Cohn, senior research scientist at MIT
+He estimates that adding the ethanol injection system to a car would cost about US$1000 (A$1300) and that cars using the new system could be in mass production by 2011. 
+"We view it as a very important near-term way to reduce oil consumption," Cohn says. 
+The scientists say their system would only use small amounts of ethanol. And Cohn estimates the ethanol tank in cars using the technology would need to be refilled every three months or so. 
+A turbocharger is added to produce more power. The ethanol injection system with the turbocharger would give a driver more power than a conventional engine of the same size, the scientists say.
+How about 'knock'?
+The higher pressures and temperatures of a turbocharged engine can lead to a problem known as knock, which occurs when the fuel and air in the engine explode prematurely, hurting performance and potentially damaging the engine. 
+Cohn says his group's technology avoids that problem by injecting ethanol into the engine when knock is likely to occur.
+The ethanol vaporises and cools the fuel-air mixture, keeping it from exploding until the engine is ready. 
+"This is a very special feature of ethanol," Cohn says.
+The researchers are developing and testing their system with car manufacturer Ford.
+
+Today, the Amazon flows into the Atlantic Ocean. But millions of years ago, it flowed in the opposite direction
+Even the most reliable geographical facts, like the direction of the world's largest river, can change dramatically over geological time. 
+Millions of years ago, a new study suggests, the Amazon River flowed from east to west, rather than the current eastward path to the Atlantic Ocean. 
+The evidence for this continent-wide reversal comes from tiny, dark, virtually indestructible minerals called zircons that are perpetually recycled in the sandstones of the Amazon Basin. 
+"People use the zircons in ancient sands to reconstruct continents, to understand what might have been upstream," says geologist Russell Mapes, a doctoral candidate at the University of North Carolina in Chapel Hill. 
+Very often zircons are the only mineral remnants of long-gone mountain ranges. 
+Geologists know this thanks to new technology that measures the age of the minerals by the minute quantities of uranium and lead isotopes within them. The isotopes reveal how long it has been since the zircon solidified from molten rock. 
+In the case of the Amazon zircons, Mapes with his US and Brazilian colleagues, discovered that the minerals don't come from the relatively young Andes at all.
+Instead, they are 1.3 to 2.1 billion years old. That strongly suggests the zircons must have eroded out of some mountain range that bordered eastern South America back when it was still attached to Africa, before there was an Atlantic Ocean at all.
+Yet the zircons were found to the west of the region where they were born, so the river must have once flowed in that direction, the researchers conclude.
+"The rocks we saw on the river suggested this," says Mapes. "But when I got the actual data back, I was happy."
+Ages later, about 65 million years ago, the Andes began to rise on the western edge of South America, blocking the river's passage to the Pacific and shifting its flow to the east. Today the zircon is all that remains of the South American-African Mountains. 
+Mapes is due to present the discovery this week at the meeting of the Geological Society of America in Philadelphia.
+"You couldn't tell this without this new tool," says geologist Dr Paul Link of Idaho State University, referring to the technology to sample individual layers of zircon minerals with precision, and then count the isotope atoms to gauge age. 
+Link is working on a similar drainage reversal in North America, even further back in time. 
+"I think that what it illustrates is that when a new tool is developed, then all of a sudden you can make interesting conclusions about which way rivers drained," he says. 
+That, in turn, can reveal how very different the world once was.
+"Even things like huge rivers are very temporary in the scheme of Earth time," says Mapes.
+
+Mastodon's faught hormonally charged battles at certain times of the year
+Battle scars on male mastodon tusks show these Ice Age giants were not the peaceful creatures once thought, according to new findings. 
+The scars reveal they fought in brutal combat each year during seasonal phases of heightened sexual activity and aggression.
+The discovery, announced at a recent Society of Vertebrate Paleontology meeting in Ontario, counters the view that now-extinct mastodons were peaceful, passive creatures that rarely engaged in battles.
+It also strengthens the link between mastodon and modern elephant behaviour, since male bull elephants also fight seasonal, hormonally-charged battles to show their dominance and win desired mates.
+Like warriors with different weapons, however, the two animals had distinct fighting techniques, says lead author Professor Daniel Fisher, a University of Michigan palaeontologist.
+"Mastodon tusks curve upward strongly at the tips and appear to have been used in a vigorous up-thrusting motion," says Fisher.
+Elephant tusks are less curved and therefore tend to be used more "in a straight thrusting move", he adds.
+Fisher's analysis of mastodon tusks and skulls reveals that such ramming caused the lower part of the tusk to rotate backward, "crunching it against the back wall of the tusk socket".
+He found that although the tusk continued to grow by adding layers of ivory to its base, pitted scars line up along the outside curve of the tusk base.
+"It's not just one event, but a whole series of events that is preserved in this tusk record of fighting," he says.
+Depends on the season
+Using previous research about mastodon tusk growth patterns, Fisher also found the scars correspond to seasonal patterns, the pits formed each year of the adult male animal's life during mid-spring to early summer. 
+Studies on mastodon vertebrae also helped fill out a picture of gory battles between the creatures, which were 2-3 metres tall.
+"For example, we have evidence of tusks stabbing into the vertebral column, penetrating the space traversed by the spinal cord, from a direction that implies the victim was already lying on his side on the ground; in other words, the violence went on, even after one animal was down," Fisher says.
+Other fossils suggest some of the animals were butchered in autumn, most likely by humans, who may have caused or contributed to the extinction of mastodons 11,000 years ago.
+Few broken bones
+Dr Jeffrey Saunders, curator and chair of geology at the Illinois State Museum, says he has excavated over 72 mastodons.
+"I always viewed them as being rather passive animals because I never found many broken bones, maybe one or two broken ribs. But I greatly respect Dr Fisher's work and I continue to be open-minded about the possibilities," he says.
+Saunders, who once found himself between two fighting bull male elephants while in a small jeep, adds, "I also think it's interesting that similarities between mastodons and modern elephants seem to persist, given that these animals parted evolutionary ways 40 million years ago. The basic elephant design must be successful to have persisted so long."
+
+A Botai village, with its horse yards, would have looked like this
+Evidence from soil inside the remains of a 5600-year-old horse yard indicates that the ancient Botai people of Kazakhstan were among the earliest to domesticate horses. 
+But the Botai probably ate and milked their horses as often as they rode them. 
+The horse yards are part of an archaeological site in northern Kazakhstan known as Krasnyi Yar.
+This was once a large village occupied by the Copper Age Botai, says Dr Sandra Olsen, curator at the Carnegie Museum of Natural History in Pittsburgh, who leads a team that has been investigating horse domestication for years.
+Associate Professor Rosemary Capo, a geologist colleague from the University of Pittsburgh, presented some of the soil evidence for horses this week at a Geological Society of America meeting in Philadelphia. 
+"We really don't understand any major signs of changes in horses with domestication," says Dr Melinda Zeder, an archaeologist at the Smithsonian Institution who specialises in the origins of animal and plant domestication. 
+Zeder refers to physical changes in horse bones from ancient middens.
+Nor, so far, is there a direct way to determine what people were doing with their horses that early on, she says.
+For these reasons she and her colleagues have been building their case with less direct evidence.
+"Here's an approach to documenting horse domestication that's extremely new," says Zeder, of the evidence presented at the conference. "Sort of like Perry Mason, they're building circumstantial evidence."
+That evidence comes from circular arrangements of posts and the soil differences found inside and outside the horse yard.
+Comparing soils
+Inside the yard, the soil contained up to 10 times the phosphorus as outside soils, but lower concentrations of nitrogen. That's what you'd expect if the soil inside the yard was enriched with horse manure.
+Modern horse manure, for comparison, is loaded with phosphorous, potassium and nitrogen. The nitrogen is the easiest to lose to groundwater or the air. 
+Phosphorus, on the other hand, can be held in place by calcium and iron, says Capo, one of the scientists who analysed the soil.
+"High phosphorous could also indicate human occupation," says Capo. "But that's usually accompanied by other geochemical signatures, which we didn't find in the [horse yard] samples." 
+There was also high sodium concentration in the horse yard samples, which could be from urine, suggests Olsen.
+Smoking gun
+The real smoking gun, says Olsen, will be if they can detect long-lived molecules of fat in these samples that can be attributed specifically to horses. That analysis is now being arranged.
+So what were the Botai doing with those horses?
+Olsen says they probably ate them and used them as pack animals. They may also have milked the mares to create a vitamin-rich, mildly alcoholic beverage that's still consumed today in Kazakhstan.
+
+Antechinus females go to extraordinary lengths to make sure their offspring survive
+Some female marsupials have sex with as many males as possible to produce the fittest and healthiest offspring, Australian researchers report.
+The brown antechinus (Antechinus stuartii) usually only breeds once in her life, so she has added pressure to make sure her young have the best chance of surviving.
+Researchers report in today's issue of the journal Nature how the mouse-like marsupial stores the sperm of many suitors for up to two weeks in her ova ducts.
+Sperm from the 'strongest' males then go on to fertilise her prized eggs. And the result may be up to eight healthy offspring sired from four strong males.
+Dr Diana Fisher and colleagues from the Australian National University conducted two separate mating experiments.
+In the first, they took female marsupials from the wild and when they were in season allowed them to mate either with a single male, or with three different males, every two days.
+A year later they replicated the experiment, but kept lactating females in captivity until just before weaning.
+This allowed the researchers to determine whether the previous benefit of polyandry depended on stressful conditions in their natural habitat, or could be replicated in the laboratory. 
+They found the females in both populations weren't particularly fussy and, given the chance, mated happily with multiple partners.
+The only males they avoided in the wild were those that were obviously picked on by other males; those perceived as 'weak'.
+"By experimentally assigning mates to females, we were able to show that polyandry [females mating with more than one male during the mating season] greatly increases offspring survival," Fisher says.
+"DNA profiling shows that males that gain high paternity under sperm competition sire offspring that are more viable."
+While many females in the animal and plant world mate with multiple partners, researchers have been at a loss to explain why. After all, the practice can be costly in terms of egg production, disease and injury. 
+Earlier studies suggested polyandry yielded genetic benefits and could increase offspring survival, but until now the reasons why were unclear and the same effects had yet to be proved for mammals in the wild.
+The researchers conclude that the practice of polyandry leads to 'better quality' offspring, an important factor in light of the fact that the marsupial will usually breed only once in her lifetime.
+
+Adverts that use thin models can make you reach for the biscuit tin
+Young women obsessed with their own body image eat more food after looking at magazine adverts that feature the 'ideal' thin body, research shows.
+But those with a healthier body image, who you might expect to be less influenced by the adverts, eat less.
+The Australian study shows that advertising affects eating behaviour, just not necessarily the way we think.
+The researchers publish their study in the November issue of the journal Eating Behaviors.
+Fiona Monro, a PhD student at the University of New South Wales, tries to explain the results.
+"We would expect people who value the way they look would be reminded by viewing the image and not eat," she says.
+"We're not sure why we found the reverse but possibly because of stress.
+"[Women obsessed with their appearance] see the idealised image and think about their own body so turn to food. They might think 'what's the point, I'm never going to look like that, I may as well eat' or the image makes them think they're thinner than they are so they eat more."
+Two hours after their last meal Monro asked 68 female university students to rank the importance of physical attractiveness, health and physical fitness to determine whether they value the way their body looks more or less than the way it functions.
+The researchers were interested in the notion of self-objectification, the way some people view themselves and their bodies as an object to be valued for external appearance.
+The women's answers categorised women as low or high self-objectifiers, with high self-objectifiers valuing appearance more.
+Participants then viewed six magazine advertisements for body-related products like diet pills, some containing images of idealised female models, some not.
+Body-obsessed people (or high objectifiers) ate more food (sweet and savoury biscuits) and sweet biscuits, after viewing idealised body adverts than adverts without models.
+Low objectifiers ate less food after seeing idealised images than the other adverts.
+"There's no doubt these images have an effect on some women and can lead to changes in eating behaviour, especially when you consider how many images people are exposed to every day," Monro says.
+She says in future eating disorders might be reduced by identifying high-objectifiers in schools, enabling education to change emphasis on appearance and promote a broader acceptance of body shapes.
+
+This footprint was made by a two-legged dinosaur that walked along a sandy beach 165 million years ago
+Scientists studying how emus walk have brought to life the mysterious moves of two-footed Jurassic dinosaurs travelling along a long-lost beach.
+Computer models have been developed to simulate the gait, and therefore the possible tracks, of specific dinosaurs.
+But live emus allow scientists to directly compare complex tracks to specific behaviours, say researchers looking at the thousands of tracks left behind 165 million years ago by dinosaurs at Red Gulch in northern Wyoming.
+Among the surprises they've found is that tracks once interpreted as steady walking may actually be created by the animals stopping at mid-stride.
+Another enigmatic type of track that now makes sense is where the dinosaurs appear to have crossed one leg over the other.
+The motion is a seemingly weird thing to do, until you watch an emu making the same sort of track, says Brent Breithaupt, director and curator of the University of Wyoming's Geological Museum.
+Emus, it turns out, have legs that are close together, like many dinosaurs, and tend to look around a lot as they walk, Breithaupt says.
+This scanning behaviour causes emus to often cross the left foot over the right leg and the right foot over the left, making the same confusing pattern seen in the dinosaur tracks.
+"Sure enough there are wonderful comparisons," says Breithaupt. "Emus are our biological Rosetta Stone."
+He presented the latest on emus as proxies for dinosaurs at the recent Geological Society of America in Philadelphia.
+The search for a modern animal to act as a proxy for dinosaur tracks started, says Breithaupt, because he was getting a little impatient with all the speculation about the tracks.
+There was too much of what he calls "prehistoric hyperbole".
+So after passing on ostriches, which have only two toes, and rheas, which have three-toes but overly rambunctious personalities, emus were the best alternative. Plus there was an emu ranch just across the state line in Colorado.
+Breithaupt and his team now think that the Red Gulch dinosaurs were probably human-sized meat eaters, or theropods, travelling along in groups.
+The groups may have included families, since there are juvenile and adults tracks together, implying some sort of parental care.
+Exactly what the dinosaurs looked like, however, is a mystery because the mid-Jurassic Period is particularly poor in dinosaur fossils in North America.
+"There is virtually nothing known about dinosaurs in North America from that time," says geologist Dr Erik Kvale, who discovered the tracks and did a great deal of the first geological work there.
+"Chances are there were some very gregarious behaviours of dinosaurs [at Red Gulch], but it's only a snapshot."
+What can be said with more certainty is that the dinosaurs were walking in a very different landscape than today, says Kvale.
+The sands beneath their feet were carbonate sands like those found in the Bahamas or the Florida Keys, but the climate of the ancient shoreline was probably a lot drier.
+"The Persian Gulf is a better analogue," says Kvale.
+
+NASA is discussing whether a shuttle mission to repair the Hubble Space Telescope is worth the risk
+After all the time, money, anguish and work to return the space shuttle fleet to flight, the US space agency still has one lingering question to resolve. Can a shuttle mission be sent to save Hubble?
+If not for the 2003 Columbia disaster, the fifth servicing call to the Hubble Space Telescope probably would have happened by now.
+That mission would have left the 16-year-old observatory with fresh batteries, replacement gyroscopes for steering and two new science instruments.
+Such upgrades could keep Hubble on the cutting edge of astronomical research, delving into questions such as the nature of the mysterious dark energy that seems to be driving the universe's expansion and what the universe looked like as its earliest structures emerged after the Big Bang.
+But after the Columbia accident shuttle flights that do not go to the space station, where astronauts can seek shelter in case their ship is too damaged to fly home, were considered too risky and the Hubble house call was cancelled.
+NASA looked into a robotic servicing mission instead, but found the cost and complexity of such a mission too daunting.
+Meanwhile, public outrage over NASA's decision to let the popular space telescope fester, culminating in a pledge by the new head of NASA to re-consider flying one last flight to Hubble.
+Now, with three post-Columbia flights complete, the time has come to decide Hubble's fate.
+NASA is considering if the safety upgrades implemented after the accident offset the risk of flying with few options available to save a stranded shuttle crew.
+"Hubble is definitely sort of the comeback kid, so hopefully it will be able to do it one more time," says Professor Adam Riess, an astronomer with the Space Telescope Science Institute in Baltimore.
+"I would expect that this is the final meeting," he adds. "Now it's a matter of coming up a with a decision."
+Shuttle program workers have certainly done their homework.
+The first order of business was to fix problems with debris falling off the ship's fuel tank during launch.
+A chunk of insulating foam broke off Columbia's tank during lift-off and smashed a hole in the wing's heat shield.
+As the shuttle attempted to return to Earth 16 days later, superheated atmospheric gases blasted into the breach, destroying the shuttle and killing the seven astronaut crew.
+NASA's first tank redesign, tested during a July 2005 flight of shuttle Discovery, failed to prevent dangerously large pieces of foam from falling off the tank. A second redesign was tested a year later, and this time the tank was deemed safe enough to resume flights.
+The shuttle program also demonstrated how the ship's robot arm and newly added extension boom could be used during flight to scrutinise the shuttle's heat shield for damages.
+Astronauts also tested using the boom as a work platform in case repairs were needed to fix heat shield holes before attempting atmospheric re-entry.
+Finally, engineers developed rudimental heat shield repair kits and techniques.
+But there is no getting around the issue of flying without an orbital safe. Hubble's orbit is too far from the station for a shuttle to get there.
+Theoretically, NASA could severely cut shuttle power and keep a crew in orbit for several weeks until another shuttle could be launched on a rescue mission. But there is no guarantee the flight could be launched on time or that another problem might not also strike the rescue ship.
+"You just don't have the orbital lifetime on a Hubble mission to be able to get another vehicle launched," says deputy shuttle program manager John Shannon.
+"We're going to have to go into the Hubble decision not counting on the launch-on-need vehicle," he says.
+"That's the difficult question the agency's going to have. Do we have enough confidence in the [tank] design? Do we have enough confidence in our inspection and repair to be able to do that? I think that's where the discussion is mostly going to lie."
+Another issue is whether to risk a shuttle and crew on a Hubble flight when NASA is under a strict deadline to finish the space station before 2010 when the shuttles are to be retired.
+The agency needs at least 14 more construction missions and wants two additional flights beyond that to deliver heavy equipment and spare parts to the outpost.
+In a recently released flight schedule, agency managers set aside a Hubble servicing mission for April 2008.
+Station assembly, which resumed with last month's flight of shuttle Atlantis, would be complete in July 2010 under the new manifest.
+Without a servicing mission, astronomers expect Hubble to last only another two or three years before its batteries give out. Even before then, the finicky gyroscopes could break or the cameras could fail.
+"It would really be a blow," says astronomer Dr Harry Ferguson, also with the Space Telescope Science Institute. "I think everyone is really quite hopeful that [a repair mission] will happen. We're waiting with bated breath."
+If it gets upgrades, Hubble should last until at least 2013. That means it could still be operational when its sharp-eyed infrared replacement, the James Webb Space Telescope, arrives in orbit to begin its five-year mission.
+The Webb observatory, which is not designed for servicing by astronauts, is scheduled for launch in June 2013.
+
+Industrial aerosols don't just affect air quality but also the temperature of our oceans
+A projected drop in air pollution will affect global ocean currents and could cause a marked rise in water temperature in the southern hemisphere, the author of a new study says.
+Dr Wenju Cai and colleagues from CSIRO Marine and Atmospheric Research are the first to model the impact of changing levels of particulate air pollution, or aerosols, on ocean currents.
+They publish their findings in the journal Geophysical Research Letters.
+Cai says air pollution like sulfate, organic particles and black carbon produced from fossil fuel burning, transport emissions and power plants, has increased rapidly over the past 50 years.
+But tighter regulation and a worldwide move towards cleaner fuels means some projections have aerosols dropping to pre-1960 levels by around 2050, Cai says.
+This, however, has a downside. Less air pollution means sunlight can more easily reach Earth, which many researchers say could mean higher temperatures.
+Cai says rises in surface and water temperature could also cause a slowdown in the so-called worldwide conveyor belt, an ocean circulation system that transports heat from southern hemisphere oceans to those in the north.
+So cleaner air will result in colder northern hemisphere temperatures and warmer waters in the south, Cai says.
+"That will have a big impact in Europe and the northern hemisphere because the conveyor belt is sending heat to that part of the globe," he says.
+"In the southern hemisphere ... we will get warmer faster and the rise in sea levels will accelerate."
+Cai says warming will be most rapid in the Tasman Sea, which could heat up by 4&#176;C by 2100, with major implications for marine life and ecosystems.
+How do aerosols influence ocean currents?
+Aerosols keep the Earth cool by reflecting away solar radiation, says Cai's co-author and CSIRO colleague Dr John Church. So, they are thought to mask some of the effects of global warming.
+But because industrial development has produced a higher concentration of aerosols in the northern hemisphere than the south, in the past the cooling effect has been more marked in the north.
+Cooler northern hemisphere temperatures should mean cooler northern oceans, and cooler waters should equate with lower sea levels.
+This wasn't the case, says Church. Instead, the study found evidence that the cooling waters had intensified movement of the conveyer belt, speeding up delivery of heat from south to north.
+Reversal
+The situation may reverse once aerosol levels fall, Cai says, effectively causing a slow-down in the transport of heat from the southern hemisphere to the north.
+Cai says an exaggerated version of this scenario was the basis for the Hollywood movie The Day After Tomorrow, in which a change in ocean currents produces a new ice age.
+Church says it's unclear exactly how dropping aerosol levels will affect global temperatures when combined with rising temperatures associated with the greenhouse effect.
+"We don't understand the aerosol forcing as well as greenhouse, so there's a question of how much of the global warming is compensated by aerosols," he says.
+"If it's a small amount, as we reduce the aerosols in the atmosphere there won't be a rapid acceleration of climate change, but if they're actually masking a very large amount then as we reduce the aerosols that has big implications."
+
+Australia is developing the world's first koala sperm bank
+Zoos around the world will soon be able to breed their own koalas without having to fly in breeding stock from Australia, researchers say.
+They say new technology to preserve sperm will allow koala sperm to be exported from Australia for the first time.
+University of Queensland reproductive biologist and team leader Dr Steve Johnston says the researchers have been able to extend the shelf life of the sperm to 40 hours.
+They've done this by diluting the semen in a special pH balanced solution containing nutrients and antibiotics, and keeping it chilled.
+The team this week unveiled eight koala joeys born from artificial insemination with the diluted semen.
+Being able to dilute the semen is the first step in being able to provide frozen specimens internationally and interstate, Johnston says.
+This is because fresh koala semen only lasts a couple of hours and the fragility of the cells means they don't easily survive freezing and thawing.
+The team now plans to set up the world's first koala sperm bank.
+What do koalas and camels have in common?
+Johnston says koalas, like camels, have a special factor in their sperm which triggers ovulation in the female. 
+"What we found was ... there's a combination between the mating itself and the factor in the semen which causes the [brain] to release luteinising hormone, which results in the ovulation process," he says.
+Diluting the semen without affecting the ovulation factor was a major challenge for researchers, he says.
+"Diluting is a first step because if you're going to freeze something you have to put it into a diluent which allows you to put cryoprotectants in the fluid to protect the sperm against freezing," he says.
+"The other thing is when you dilute the sperm you don't have to use as much, you don't waste as much sperm when inseminating."
+Low sperm count
+Koalas have a relatively low sperm count with only about 100 million sperm per ejaculation, compared with echidnas, which have 10 times that amount.
+Johnston says being able to send a frozen sperm sample internationally will make it easier to introduce genetic diversity to koala populations.
+And setting up a sperm bank will help conservation efforts in Australia and enable samples to be screened for common koala diseases like chlamydia and retroviruses.
+But don't hold your breath about buying your very own koala sperm online, Johnston says.
+"The Queensland government is making sure that none of that will happen."
+
+Mathematicians say you can have your cake and eat it too, if you're prepared to do the sums
+Mathematicians have devised a fairer way to share a cake, according to new research.
+It allows you to choose a slice with more chocolate icing. But the trade-off is that you get a smaller piece.
+The research, which is based on the principle of surplus procedure, is published in the Notices of the American Mathematical Society.
+The traditional way of dividing a cake is the 'cut and choose' approach, where one person cuts the cake in two and the other chooses a half, write Professor Michael Jones and colleagues from Montclair State University in New Jersey.
+While this ensures both people get the same sized portion, it doesn't necessarily mean they are equally happy.
+For example, one may like chocolate icing, sprinkles or cream more than the other.
+Surplus procedure
+To even this out, the researchers propose people tell a referee how much they value certain qualities of a cake.
+The referee then uses these weighted values to calculate where to cut the cake.
+In an ideal world, both parties would get 100% of what they want. But in reality there's a compromise.
+Jones says his team's algorithms ensure that both parties get about 65% of what they want, based on the principle of giving each person at least 50% of the cake plus the surplus as they value it.
+The catch is that the system depends on honesty and requires a referee and a calculator.
+The surplus procedure system can be used for two or three people, Jones says, but doesn't work quite as well for three or more.
+He says the method can also be applied to other heterogeneous and divisible items, like dividing land or deciding how much rent each flatmate pays.
+The wedge system
+Dr Burkard Polster, an Australian mathematician from Monash University, isn't convinced the proposed method is best.
+"How do you associate a number with something like happiness?" he says.
+"If you really wanted to sell this to a 10 year old, they wouldn't go for it, They'd still think the other piece is better."
+He says a square cake, for example, can be cut into five fairly by using the equation that says the area of a triangle equals the length of its base times its height, divided by two.
+The cake can't be cut into equal squares because there will only be four pieces. And it can't be cut into parallel pieces because the pieces on the edge will have more icing (if the cake is iced around the edge and not just on top).
+The answer is to cut the cake in equally sized wedges.
+"If the cake has a perimeter of 50 centimetres, you start at one corner and measure 10 centimetres and make a mark, then you go around until you're back to the beginning and you have five marks.
+"From those marks you cut through the middle and those wedges will be exactly one fifth."
+Eggs and sandwiches
+Polster says applying surplus procedure to cakes isn't the first time maths has been used to share food.
+The 'egg yolk' theory describes how best to divide a fried egg into pieces with an equal portion of yolk and white.
+And he says the 'ham sandwich' theory makes sure you can cut a sandwich and get equal amounts of ham, lettuce and bread.
+
+A vending machine containing a new type of printer could churn out a novel in an instant
+An innovative printer head may lead to affordable printers that spew out a thousand pages per minute, its developers say.
+Such printers could lead to fast, high-quality photo printing as well as on-demand printed media, say the researchers.
+Imagine customised newspapers and magazine and instant books printed by a vending machine.
+"Think of such a machine in an airport terminal. You slide your credit card, chose a [book] for your flight, and get it warm from the printer in less than a minute," says Dr Moshe Einat, senior lecturer at the College of Judea and Samaria in Ariel, Israel, and team member.
+The JeTrix printer head, invented by colleague Nissim Einat and team, could be on the market in two years in printers costing U$500-U$1000, the researchers say.
+The machine could reduce backups at the office printer too.
+Today, even the best printers used for business purposes cost thousands of dollars and max out at about 50 pages per minute.
+The speed is limited, in part, by the printer head. For starters, it's usually much smaller than the page and takes time to scan back and forth while applying the ink.
+Nozzle redesign
+The other challenge has to do with the nozzles.
+The ink is typically pooled in a main reservoir and distributed through a chamber, or manifold, that has many branching tubes, each leading to a nozzle.
+To get uniform drops, the pressure of the ink in this system must be precisely regulated and maintained, a delicate task that becomes more difficult as the number of nozzles and the size of the nozzle array increases.
+Overcoming obstacles
+The JeTrix overcomes conventional limitations in two ways. First, it does not have a main reservoir or manifold that requires delicate pressure maintenance. Second, it is not limited by size. In fact, it can be as large as piece of paper and theoretically has a nozzle for every pixel.
+The difference has to do with the way Einat and his team built the printer head. They turned to the same technology used to manufacture computer chips, etching the printer head out of silicon wafer chips.
+Instead of a small array of nozzles that makes many scans to print a page, the design is a flat, 2D panel designed to be as big as the page and eject all of the necessary ink simultaneously.
+Although the approach has a number of innovative features, it also has limitations says Dr Ross Allen, an internationally recognised technologist based in St Helena, California, who has 40 patents in imaging and printing technology.
+"Inkjet print heads typically make two to eight passes over the same pixel row in order to hide any defects caused by nozzles that don't operate or meet drop ejection specifications," says Allen.
+"If Einat's print head lays down all of the ink at once, the printed page could show artefacts or flaws from 'bad' nozzles."
+Printing in colour
+Printing in colour could also present a challenge.
+"You'll need black, cyan, magenta and yellow page-size print heads printing in precise registration," says Allen.
+Finally, he says, no matter how fast a printer head applies ink, it doesn't get around the basic limitation that the ink must dry before the page is stacked in the paper tray.
+
+Who's that? Oh, it's me
+When presented with a jumbo-sized mirror, elephants recognise their reflections and investigate the inside of their mouths and ears, according to a new study.
+Such self-awareness is rare. Until the paper, published online today in the Proceedings of the National Academy of Sciences, scientists believed only humans, apes and dolphins possessed self-recognition skills.
+All these animals are highly intelligent and seem to feel empathy, a quality that is probably linked to self-awareness.
+"What they have in common is complex sociality that includes high levels of cooperation, altruism and large brains," says co-author Dr Frans de Waal, a psychology professor at Emory University in Atlanta.
+"In literature about human children, there is speculation as to how increased self-awareness makes it possible to set the self apart from others, which in turn permits the self to take the other's perspective, a prerequisite for complex forms of empathy," says de Waal, director of the Living Links Center at the university's Yerkes National Primate Research Center.
+For the study, de Waal and colleagues Dr Diana Reiss and Joshua Plotnik introduced three adult female Asian elephants - Happy, Patty and Maxine - to a large mirror placed in their exhibit at the Bronx Zoo in New York City.
+According to the paper, animals typically have a social response towards the reflection they see in the mirror. They then try to inspect the mirror, such as by looking behind it. Most animals, such as parrots, dogs and cats, show these behaviours.
+But the three elephants had different reactions to their reflections. Each elephant played a sort of peek-a-boo by swaying their heads, trunks and bodies in and out of mirror view. They even brought food in front of the mirror and watched themselves eat.
+Maxine took her trunk and stuck it in her mouth, as though she were investigating the inside of her oral cavity. She also used her trunk to pull her ear slowly forward towards the mirror.
+X marks the spot
+The researchers next painted two X marks on the foreheads of the elephants. One mark was invisible to control for odour and tactile cues, the other fully visible.
+This 'mark test' is the scientific standard for determining whether an animal recognises itself in a mirror.
+As soon as Happy saw the visible mark, she touched it with her trunk in front of the mirror. She did this 47 times. Maxine and Patty, however, ignored the marks on their foreheads.
+"We believe that because elephants love to dust-bathe and throw food and dirt on their backs for storage, such a relatively small mark on their head might not bother them," says Plotnik.
+"Chimpanzees and humans groom themselves by picking things off their bodies, while elephants love to be covered in dirt and mud."
+Hardly surprising
+Dr Lori Marino, a senior lecturer in neuroscience and behavioural biology at Emory, worked on the earlier dolphin-mirror study. 
+She is not surprised that elephants can recognise themselves in the mirror.
+"Like dolphins, great apes and humans, elephant brains are large and highly convoluted and their social lives are extraordinarily complex," Marino says.
+She adds that many other animals possess self-awareness, a multi-faceted, complex phenomenon, which seems to manifest itself at different levels.
+Since elephant self-awareness and empathy are on a similar level to that of humans, Plotnik hopes the findings will strengthen our commitment towards conservation, especially as the wild elephant population continues to plummet due to habitat loss and poaching.
+
+A shuttle mission in 2008 will be the Hubble Space Telescope's final service call
+The US space agency says it will launch a final space shuttle mission to keep the ageing Hubble Space Telescope in orbit and operational. 
+The decision, announced this week by NASA chief Dr Michael Griffin, follows a review of safety concerns and appeals from the scientific community to extend Hubble's life. 
+Without a repair mission, which will probably be carried out in 2008, the telescope would shut down in 2009 or even earlier. 
+Since it was launched into orbit 16 years ago, the telescope has helped astrophysicists peer deep into the universe, free of the distortions from the Earth's atmosphere.
+Orbiting 575 kilometres above the Earth, the Hubble has enabled scientists to better measure the age and origins of the universe, observe distant supernovas, and identify and study bodies in and outside the solar system. 
+In 2004, it conveyed pictures of the most distant parts of the universe ever observed by visible light, "the deepest portrait of the visible universe ever achieved by humankind", says the Space Telescope Science Institute. 
+NASA had scheduled a mission for Hubble in 2003, but scrapped it after the Columbia shuttle disintegrated while returning to Earth. 
+The accident raised serious safety questions for NASA, particularly with the shuttle's heat shield.
+This week's announcement comes after two of the last three shuttle missions were judged a success.
+Safety review
+Griffin says the decision to go ahead was taken after a painstaking review of safety issues.
+"We're not going to risk a crew in order to do a Hubble mission," he told staff at the Goddard Space Center.
+NASA has said previously it was ready to refurbish the telescope as long as the mission did not put the space shuttle crew in jeopardy. 
+The Hubble mission presents a challenge because the shuttle crew would not be able to seek refuge aboard the orbiting International Space Station if a serious problem arose.
+NASA also is faced with a busy schedule of another 15 missions to finish building the space station before retiring the entire shuttle program in 2010, or four missions a year. 
+A Hubble mission would probably be set for early 2008 and would require a second shuttle to be ready for any rescue mission should the crew face an emergency. 
+A new mission to the Hubble would replace the telescope's six stabilising gyroscopes and its batteries to extend its life. 
+Astronauts would also repair an infrared spectrometer that has been broken since 2004.
+They would also install two new instruments, including the Wide Field Camera 3 that would enhance images of dark matter and of the first galaxies that were formed after the Big Bang.
+
+Putting babies to sleep on their backs allows them to respond to their arousal reflexes
+An abnormality in part of the brain that controls breathing, arousal and other reflexes may be what causes sudden infant death syndrome, a finding that could lead to a preventive treatment, a study says.
+The discovery could explain why babies lying face down are more likely to die of SIDS.
+In that position an infant's reflexes, including head turning and arousal, are harder to trigger when breathing is challenged, says the report from Children's Hospital Boston and Harvard Medical School.
+The study, published in this week's Journal of the American Medical Association,  was based on autopsy data from 31 infants who had died from SIDS and 10 who had died from other causes between 1997 and 2005 in California.
+In the SIDS infants, a look at the lowest part of the brainstem, the medulla oblongata, found abnormalities in nerve cells that make and use serotonin, one of the chemicals in the brain that transmit messages between nerve cells. 
+Serotonin and how it is processed in the brainstem may help coordinate breathing, blood pressure, sensitivity to carbon dioxide and temperature, the report says.
+When babies sleep face down or have their faces covered by bedding, they are thought to breathe exhaled carbon dioxide back in, depriving them of oxygen.
+When that happens the carbon dioxide increase would normally trigger nerve cells in the brainstem, which in turn stimulate respiratory and arousal centres in the brain. 
+"A normal baby will wake up, turn over, and start breathing faster when carbon dioxide levels rise," says Dr Hannah Kinney of the Boston hospital, an author of the paper. 
+But babies with the defect die because the reflexes are impaired, she says. 
+Public health campaigns aimed at reducing the risk of SIDS have advised parents to put infants to sleep on their back, and to avoid soft bedding, sharing a bed with an infant, smoking during pregnancy and smoking around a baby after birth.
+Among the SIDS infants in the new study, 65% were sleeping prone or on their side at the time of death, indicating a need for continued public information on the problem, the study says. 
+The findings may spur development of a diagnostic test to identify infants at risk, or perhaps some day a drug or other type of treatment to protect infants with abnormal brainstem serotonin systems, the authors say. 
+"This finding lends credence to the view that SIDS risk may greatly increase when an underlying predisposition combines with an environmental risk, such as sleeping face down, at a developmentally sensitive time in early life," says Dr Duane Alexander, director of the US National Institute of Child Health and Human Development, which helped to pay for the study.
+
+'Serious games' are being developed to teach the US military how to defuse tense situations in Iraq
+Gamers are increasingly dropping virtual swords and guns, and picking up serious subjects such as cancer or the Iraq war, injecting a dose of reality into the multi-billion dollar sector.
+A two-day Serious Games Summit near Washington saw some 500 game designers, publishers, academic experts as well as representatives from the defence and health sectors share information about new 'serious games' on the market that deal with real-world issues. 
+"Serious games are games used for some other serious pursuit than entertainment," says Ben Sawyer, co-director of the Serious Games Initiative, which held its first summit two years ago.
+Among games featured at the summit were The Redistricting Game, which teaches administrators how legislative redistricting works; HumanSim, which tests medical diagnostic skills; and Tactical Iraqi, a program to train US soldiers with linguistic and cultural skills needed for missions in Iraq. 
+That game, largely funded by the US Department of Defense, encourages soldiers who face various scenarios with virtual Iraqis to use diplomacy to avoid or defuse tense situations. Players are also familiarised with basic Iraqi culture.
+In one episode, for example, two soldiers seeking information from local Iraqis sitting in a cafe are shown how to introduce themselves to make clear they are not a threat and are told to take off their sunglasses as eye contact is important in Iraqi culture. 
+"Clearly, in hindsight, a lot of this training should have been done earlier, but the military recognises it now, and is serious about it now, and I see this as being a permanent change in the military," say Lewis Johnson, chief executive officer of Tactical Language and Culture, a California-based company that developed the game.
+"At this point the US military is really taking the lead in emphasising the importance of understanding other cultures, other languages, the importance of communication," he adds.
+Johnson says a number of countries have expressed interest in his company's products, which include Tactical Pashto and Tactical French for soldiers or civilian contractors working in Afghanistan or in French-speaking African countries. 
+He says the company is also seeking to develop games for the general public and to be used in schools.
+Johnson, Sawyer and others attending the summit say they believe the serious games sector will gain popularity in coming years as more funding becomes available and as the Super Mario generation comes of age. 
+"Serious games has got very far to go, but in a good way that is nowhere but up," Sawyer says.
+"As we start to unlock where we can use games and where they can be successful, and as commercial gaming hurdles forward and we can gain by trailblazing technology they churn out, the things we will be able to do two to three years from now will be more amazing." 
+Sawyer says he expects the next big success story to be a serious game being developed to enable students to design their own game on a certain topic.
+"Instead of writing a term paper, you might design a game about running a state park, owning a hotel or running an office," he says.
+
+The traffic lights don't need a master controller to 'tell' them when to change
+A network of traffic lights that decides to turn green when lots of cars are waiting can help reduce traffic jams, say researchers.
+Unlike other traffic light systems that are coordinated centrally, these lights would optimise traffic flow by acting autonomously.
+Seung-Bae Cools of the Vrije Universiteit Brussel in Belgium and colleagues report their findings in a paper posted on the arXiv  preprint website.
+Traffic management aims to optimise traffic flow, reduce traffic jams and cut the time drivers spend waiting at traffic lights.
+Green lights are synchronised into 'green waves' to allow cars to flow through the main avenues of cities without facing a red light.
+The idea is to make the speed of the green wave match the desired cruise speed for the street.
+But if the green waves remain the same whatever the traffic condition, this can lead to traffic problems.
+When traffic is heavy, cars entering a green wave will stop as there are cars ahead of them. And once a car misses the green wave it has to wait the whole duration of the red light to enter the next green wave. 
+Self-organising traffic lights
+Most advanced traffic control management systems rely on a central computer to help optimise the flow of traffic.
+But the Belgian researchers have developed a system that relies on "self-organising traffic lights".
+They say the system relies purely on "local interactions between cars and traffic lights" to generate "flexible green waves on demand".
+At each traffic light, there is a counter that is set to zero each time a light turns red and then counts the number of cars that build up at the lights.
+"If there are more cars approaching or waiting behind a red light, this will turn into green faster than if there are only few cars," say the researchers.
+The researchers say the system can greatly improve traffic flow and they have tested this by feeding real traffic data from a Brussels avenue into a traffic simulator.
+Adapting to traffic conditions
+But Brent Stafford of Intelligent Transport Systems Australia is not convinced the system does better than the latest 'adaptive' traffic light systems.
+As the name suggests, adaptive systems adjust to current traffic conditions, rather than say trigger green lights set on a timer.
+One existing adaptive system, developed in Australia in the 1970s, is the Sydney Co-ordinated Adaptive Traffic System (SCATS) that now controls about 60,000 intersections in 40 countries around the world, says Stafford.
+He says the Belgian researchers compared their system to a less sophisticated system to this and he is not sure how realistic the traffic simulator they used was since it is non-standard.
+Panacea for traffic jams?
+And other experts warn against thinking such technology can be a panacea for traffic jams.
+"At the end of the day you will not be able to resolve traffic jams using just this particular concept," says traffic control engineer Professor Ljubo Vlacic of Australia's Griffith University.
+The Belgian researchers agree, saying efficient traffic control should not be an excuse to keep increasing the number of cars on our roads.
+They stress alternatives to private cars such as cycling, walking, car sharing and public transport play an essential role.
+
+The red wine molecule seems to mimic the benefits of eating less without the effort of dieting. But will it work in humans?
+A compound in red wine and grapes can extend the life span of obese mice and help them enjoy a healthier old age, scientists say. 
+The molecule known as resveratrol not only enabled the mice to live longer than other overweight rodents, it also reduced the negative health effects of eating a high-calorie diet. 
+Resveratrol has been shown to have same effect in studies on yeast, flies and worms. But the scientists say their research is the first to show it works in mammals.
+"It is possible to find a molecule that activates the body's natural defences against ageing. You can use it to enhance the health of a mouse or mammal. That is unprecedented," says Associate Professor David Sinclair, of Harvard Medical School. 
+He adds that the study, reported online today in the journal Nature, is proof of the principle that it works in mammals.
+But the real test will be to develop formulations or find other molecules to treat age-related illnesses such as diabetes, Alzheimer's, heart disease and cancer in humans.
+Researchers already know that restricting calories can prolong life in mice and other organisms.
+Resveratrol seems to mimic the beneficial effects of eating less without the hassle of dieting. 
+Middle-aged mice
+Sinclair and an international team of scientists, including Australian researchers from the University of Sydney, analysed the impact of the molecule by studying three groups of middle-aged mice.
+One group ate a standard diet, the second a high-calorie diet and the third had the same diet but were given supplements of resveratrol. 
+Eight weeks after starting the study, the scientists noticed a difference between the two high-calorie groups.
+By the time the mice were 114 weeks old, 58% in the high-calorie group had died, compared to 42% in the other groups. 
+"After six months, resveratrol essentially prevented most of the negative effects of the high-calorie diet in mice," says Dr Rafael de Cabo, a co-author of the study from the US National Institute on Aging.
+The study is continuing but so far the compound has extended the life span in the high-calorie mice by about 10-20%. 
+"There is no question that we are seeing increased longevity," says Sinclair. 
+In addition to increasing survival, the compound reduced the negative effects of being obese so the mice treated with resveratrol lived as long as the lean mice. 
+They had healthier heart and liver tissue, decreased blood sugar levels, better insulin sensitivity and were more active than the other rodents. 
+Which genes are involved?
+When the scientists looked at the genetic level, to see which genes in the mice were switched on or off, they found the molecule had changed the gene expression pattern of the obese mice towards that of lean mice. 
+The next step is to understand how the compound works. 
+Sinclair and his colleagues believe a key component could be the SIRT1 gene, which is thought to be linked to life span extension. 
+Sirtris Pharmaceuticals, a therapeutics company co-founded by Sinclair, has started a trial of a proprietary formulation of resveratrol in patients with type 2 diabetes.
+"The real bang will be if somebody proves this is going to work in people," Sinclair adds.
+
+Pigs are the most important domestic animal of the Pacific
+Sacred pigs from Vanuatu are shedding new light on how domestic pigs spread throughout the world, say US and Australian researchers.
+Dr Koji Lum, from Binghamton University in New York State, and colleagues publish their study on Pacific island pigs in the Proceedings of the National Academy of Sciences.
+Pigs are the most important domestic animal in Pacific cultures, being an important source of food and a basis for societal wealth.
+They are also sacred animals that some cultures believe have souls.
+Yet the origin of Pacific pig breeds has long been unresolved.
+Lum and team studied mitochondrial DNA, or mtDNA, from two kinds of sacred pigs from the island nation of Vanuatu.
+One was a male of the Narave type. These intersex pigs don't produce enough steroid for complete masculinsation, say the researchers. So they cannot reproduce amongst themselves.
+The breed is therefore carried forward by female carriers of the Navare traits.
+The second type of sacred pig was the hairless Kapia.
+Lum and team, which includes Kirk Huffman from the Australian Museum, compared mtDNA of the pigs from Vanuatu to mtDNA from pigs from Burma, Vietnam, China and the Ryukyu Islands.
+They found that the Narave pig DNA matched the DNA of those breeds domesticated in southeast Asia over 3000 years ago.
+"[This data suggests the Navare] pigs were recently domesticated within southeast Asia and dispersed during the human colonisation of remote Oceania associated with the Lapita cultural complex," write the researchers.
+Interestingly, the researchers found that the other native Pacific pig they studied, Kapia, shared much of its DNA with introduced European breeds.
+Two thirds of the DNA from the Kapia pig samples came from Berkshire and Large Black breeds introduced by Europeans.
+The researchers say these breeds would have been chosen for crossing with native breeds because they had the same dark coat as the natives, ensuring the offspring remained protected from the tropical sun.
+'Nice, but only half the story'
+A previous study comparing pig skulls, by Professor Colin Groves of the Australian National University, also concluded southeast Asia was the most likely origin of Pacific pigs.
+"[The Lum study is] a nice little confirmation of what we already suspected," says Groves.
+But he says using mtDNA, which comes through the maternal line, means the researchers are only finding out the origin of the female pigs.
+"They're only getting half the story here," he says.
+Groves says if they tested the DNA from the Y chromosome of the Kapia, for example, they may find the main source of the recently introduced pig DNA was via the use of introduced boars rather than sows.
+Groves says that while most of the domestic pigs that are widespread in the world today come from Europe, they are actually ultimately of either Chinese origin or half Chinese and half European.
+He says European farmers bred their pigs with the fatter Chinese breeds to get a better domestic animal.
+
+In less than 50 years, fish markets like this one in India may not have any produce to sell
+The world's fish and seafood populations will collapse by 2048 if current trends in habitat destruction and overfishing continue, resulting in less food for humans, researchers say. 
+When they analysed scientific data going back to the 1960s and historical records over a thousand years, they found that marine biodiversity - the variety of ocean fish, shellfish, birds, plants and micro-organisms - had declined dramatically. Some 29% of species were already in collapse. 
+Extending this pattern into the future, the scientists calculate that by 2048 all species would be in collapse, which the researchers defined as having catches decline 90% from the maximum catch. 
+This applies to all species, from mussels and clams to tuna and swordfish, says Assistant Professor Boris Worm, lead author of the study, which is published today in the journal Science. 
+Ocean mammals, including seals, killer whales and dolphins, are also affected. 
+"Whether we looked at tide pools or studies over the entire world's ocean, we saw the same picture emerging," says Worm, from Dalhousie University in Halifax, Nova Scotia.
+"In losing species we lose the productivity and stability of entire ecosystems. I was shocked and disturbed by how consistent these trends are, beyond anything we suspected."
+When ocean species collapse, it makes the ocean itself weaker and less able to recover from shocks like global climate change, Worm says. 
+The decline in marine biodiversity is largely due to overfishing and destruction of habitat, says Worm.
+Over-exploitation
+The loss of biodiversity makes ocean ecosystems less able to recover from the effects of global climate change, pollution and over-exploitation, Worm says. 
+He likens a diverse ocean environment to a diversified investment portfolio. 
+With lots of different species in the oceans, just as with lots of different kinds of investments, "you spread the risk around", Worm says. 
+"In the ocean ecosystem, we're losing a lot of the species in our stock portfolio, and by that we're losing productivity and stability. By losing stability, we're losing the ability of the system to self-repair."
+To help depleted areas rebuild, marine-life reserves and no-fishing zones need to be set up, the authors say. 
+With marine reserves in place, fishing near the reserves can improve as much as four-fold, Worm says. 
+Beyond the economic benefits to coastal communities where fishing is a critical industry, there are environmental benefits to rebuilding marine biodiversity, the scientists say. 
+Depleted coastal ecosystems are vulnerable to invasive species, disease outbreaks, coastal flooding and noxious algae blooms, they report. 
+Certain kinds of aquaculture, like the traditional Chinese cultivation of carp using vegetable waste, can also be beneficial, according to the scientists.
+But farms that aim to raise carnivorous fish are less effective.
+
+Mercury will cross the face of the Sun early Thursday morning Australian time, just like it did when this image was taken in 2003
+Australians are in a prime position to see Mercury moving across the Sun this week, an event they won't be able to see again for another 26 years.
+The transit, which can be seen using amateur telescopes on Thursday morning Australian time, is of particular interest to historians.
+Astronomer Dr Nick Lomb of Sydney Observatory says the transit of Mercury in 1677 was the original astronomical event that triggered European colonisation of Australia, and not the transit of Venus, as commonly thought.
+"There is a very direct link between the transit of Mercury and the fact that we are here and speak English in Australia," says Lomb.
+On 7 November 1677 Edmond Halley witnessed a transit of Mercury from the south Atlantic island of St Helena. 
+Lomb says this led him to suggest the idea that planetary transits could be used to work out the scale of the solar system, in particular how far the Earth was from the Sun.
+And this eventually led to James Cook's voyage to Tahiti to observe the transit of Venus in 1769, which in turn resulted in the British colonisation of Australia.
+Today, scientists use the transit of Mercury and Venus to study the chemical composition of the planets' atmospheres.
+As a planet passes in front of the Sun, scientists can use spectroscopy to deduce information about its atmosphere by comparing the difference in the electromagnetic spectrum given off by the Sun and the planet.
+Transits can also be used the study the momentary dimming of stars as a planet passes in front of it, a phenomenon used to detect planets circulating stars other than the Sun.
+Mercury transits the Sun on average 13 times a century, says Lomb, more frequently than Venus, which only transits twice a century. 
+Transits of Mercury occur in either May or November (when Mercury is closer to the Sun) and the next one will not occur until 2016. 
+The next transit visible from Australia will not be until 2032.
+
+A targeted approach to weeds, rather than spraying the whole field, could reduce costs and be safer for humans and the environment
+A solar-powered robot could help farmers pinpoint and destroy weeds, significantly reducing the use of herbicides, its developers say.
+The autonomous agricultural robot or AgBot has been designed by engineers at the University of Illinois at Urbana-Champaign.
+It uses cameras and vision recognition software to seek out weeds, cut them down and apply a precise amount of herbicide to the root.
+The targeted approach requires fewer chemicals and minimises the risk that they will get into the environment, whether carried by wind or water.
+Farmers typically apply herbicide to the entire field, making no distinction between crop and weed.
+The herbicide can become airborne or, if it rains, leech into ground water. If inhaled or ingested in large quantities, some herbicides can be harmful to people.
+Hong Young Jeon, a PhD candidate in agricultural and biological engineering, and Nathanael Gingrich, a master's student at the university, saw an opportunity to address the problem.
+Working under the direction of agricultural engineer Associate Professor Lei Tian, the team built a robot about 1.5 metres long and 70 centimetres wide.
+Solar powered
+A curved solar panel mounted to the top gathers solar energy to charge a battery.
+And the battery powers two small cameras, sensors, a GPS for navigation and an electric motor that drives the robot about 5 kilometres per hour.
+The panel also serves as a canopy to protect the machine from the elements and provides shade for the vision system.
+The vision system, although still in the beginning stages of development, will be designed to recognise the shape and structure of plants and be able to distinguish between a weed and a corn plant.
+When a weed is spotted, a robotic arm attached to the front of the machine cuts the weed and then squirts herbicide onto the root.
+The vision system will also allow the machine to recognise when it has arrived at the end of a row and to turn down the next lane.
+Currently an operator controls the robot, but eventually it will work autonomously. 
+And a wireless connection between the robot and a laptop computer could make it easy for the farmer to operate the machine from the comfort of his house.
+"The farmer could control everything from the living room," says Jeon.
+Worth the cost?
+S&oslash;ren Marcus Pederson, a senior research fellow at Denmark's Royal Veterinary and Agricultural University in Frederiksberg, says surveys show that farmers are generally receptive to new technologies. But there has to be an economic advantage.
+For example, using a small machine might require less fuel and would not compact the soil the way heavy machinery does. There is a cost associated with the labour needed to undo the compacting that occurs each year, says Pedersen.
+But a cost advantage may be hard to see on low-value crops such as rice and corn.
+"It's difficult for me to see a huge breakthrough in cereal crops. You have to start to focus on vegetables, potatoes and sugar beets, crops that have a relatively high value," says Pedersen.
+Reliable?
+And the robot's safety system would have to be reliable enough for it to operate autonomously.
+"It's relatively costly to implement safety features on these robotic systems," he says.
+"In principle, they can work the whole day, but if there is a requirement that it has to be attended, then you have to limit your time for using these systems."
+
+There will still be fish on the menu, governments say, despite warnings that stocks will be depleted within 50 years
+Governments and the UN food agency have cast serious doubts on a major scientific study that predicts all marine fish and seafood species face will collapse by 2048.
+The UN Food and Agriculture Organization (FAO) says that the conservation effort must be improved.
+But it says that it is "unlikely" there would be no seafood on consumers' plates by mid-century, calling the report "statistically dangerous". 
+"Such a massive collapse ... would require reckless behaviour of all industries and governments for four decades, and an incredible level of apathy of all world citizens to let this happen, without mentioning economic forces that would discourage this from happening," says Serge Michel Garcia, director of the FAO's fishery resources division.
+South Korea's fisheries ministry labelled the report "too radical", and says more scientific data is needed before heeding the call of environmentalists like Greenpeace to set aside 40% of oceans as marine reserves.
+The cry for urgent action came in the wake of a report published in the current issue of the journal Science.
+In the most exhaustive study conducted to date, US and Canadian researchers warned that overfishing and pollution threatened the accelerated loss of ocean species, ecosystems and human food supplies. 
+The worldwide fishing industry currently extracts some 80 million tonnes of fish each year from the world's oceans, according to the FAO.
+It represents a significant economic sector in many countries, including Scandinavia nations, where officials expressed scepticism about the report's conclusions.
+"I don't think the oceans will be empty in 50 years time," says Helga Pedersen, the Norwegian minister of fisheries.
+"That said, we have to work harder to secure sustainable management of fish stocks," she adds. 
+Nordic fishing unions say industrial overfishing is not, in any case, the main culprit.
+"Sure there are threatened species, but pollution is the main problem," says Lena Talvitie, vice-president of the Finnish federation of professional fishermen.
+For environmentalists, however, the report's message was unequivocal. 
+"Overfishing and pirate fishing are destroying our oceans at an alarming rate," says Greenpeace spokesman Nilesh Goundar in Australia. 
+Some 29% of 8000 fished species were considered "collapsed" in 2003, that is, their catches had declined by 90% or more," says Assistant Professor Boris Worm of  Dalhousie University in Canada, lead author of the report.
+The European Commission reacted by urging better international cooperation to turn around any doomsday scenario on the world's marine fish supply.
+
+Mice engineered to have a low body temperature live longer, scientists show
+Lowering the body temperature of mice without limiting the amount of food they eat can prolong their lives, a new study shows.
+According to a study in the latest issue of the journal Science, female mice live up to 20% and males 12% longer.
+"Our study shows it is possible to increase life span in mice by modest but prolonged lowering of core body temperature," says Bruno Conti, an associate professor at Scripps Research Institute in California, who led the study.
+But it will take a long time to determine if the same applies to humans, the researchers say.
+Scientists know that body temperature and ageing are linked in reptiles and other cold-blooded animals. 
+They also know that the life span of warm-blooded creatures can be extended by reducing the number of calories they eat, which in turn lowers the body temperature by slowing down the metabolism.
+So, the researchers carried out the study to determine whether calorie reduction is indeed responsible for extending animals' life, with a lowering of the body temperature being a secondary effect, or whether the latter is actually the cause of the increased longevity. 
+They found that the increased life span is due to the lower body temperature, independent of the amount the mice eat.
+Cooling down a mouse
+In the study, the researchers lowered the body temperature of the mice 0.3-0.5&deg;C by genetically manipulating them.
+They created mice that produce large amounts of a type of protein in the brain. This acts to heat up the brain's thermostat, a region of the hypothalamus. And the thermostat responds by reducing the core body temperature.
+What about humans?
+Professor Clifford Saper from the Beth Israel Deaconess Medical Center says that if core body temperature is critical in extending the life spans of mammals, "one might wonder whether 37&deg;C is indeed the optimal body temperature for humans, and why evolution has not selected for a lower body temperature and longer life span".
+But before we look at manipulating how long humans live, he says "one would certainly want to know the consequences of hypothermia before pursuing it as a way to increase life span".
+
+Could proposed new copyright laws restrict what you can get from a Google search?
+Plugging a word or phrase into a search engine may soon give you fewer results if proposed new Australian copyright laws are adopted, according to internet giant Google.
+The laws could open the way for Australian copyright owners to take action against search engines for caching and archiving material, Google says in a submission to a senate committee considering the legislation.
+This could potentially limit the scope of the search engine results, which the internet company describes as effectively "condemning the Australian public to the pre-internet era".
+Earlier this year the federal government announced its proposed changes to copyright law, which it says are designed to keep up with the rapidly changing digital landscape.
+But in the submission to the senate legal and constitutional affairs committee, senior counsel and head of public policy at Google Inc, Andrew McLaughlin, says the changes fail to take into account the realities of the way in which information is processed and provided online.
+"Google believes that the bill fails significantly to bring Australia's copyright act fully into the digital age," the submission says.
+The internet company wants general "safety valve" provisions, as well as specific copyright exemptions, to protect search engines from falling foul of the law. 
+"Given the vast size of the internet it is impossible for a search engine to contact personally each owner of a web page to determine whether the owner desires its web page to be searched, indexed or cached," Google submits.
+"If such advance permission was required, the internet would promptly grind to a halt."
+Google is also concerned about the effect of the copyright laws on digitisation projects, like its book search, which allows users to download books from the internet.
+ Authors, news organisations and porn sites
+Dr Matthew Rimmer, a copyright law expert from the Australian National University, says Google's concerns are justified and that the current laws haven't considered the crucial role search engines play in organising and providing information.
+Google has already attracted legal action from the French press agency AFP, as well as authors and publishers in the US, he says.
+The internet company is also appealing a decision which found in favour of a California pornographic company's breach of copyright claim against it.
+Rimmer says internet search engines could be "crippled" by the proposed copyright changes, which protect libraries, archives and research institutions but leave commercial entities like Google out in the cold.
+He says this will affect the ability of search engines to engage in digitisation projects like book search, provide images, index news stories and archive web content.
+"Given the amount of litigation that Google has been involved in the last year I think they've got very genuine fears that they could be subject to copyright actions in Australia," he says.
+He says rather than adopting the narrow "fair use" definitions contained in the legislation, Australia should adopt a US-style open-ended fair use defence to ensure a flow of and access to information.
+"In the past when Google has been sued ... one of the things it did is take down its links and content.
+"Google could very well become more reluctant to provide such comprehensive image and news services ... and with geo-identification technology you can also offer certain content in some countries and not others."
+A spokesperson for attorney general Philip Ruddock says the committee has received 70 submissions, including one from Google, and all would be taken into account when considering the legislation.
+"We will take on board all the submissions and the committee will take their views into account when they do their report," he says.
+Submissions will be discussed at a public hearing in Canberra today.
+
+Scientists hope they have a new way of tackling HIV/AIDS a bit like a Trojan Horse. They've engineered a 'faulty' version of HIV, infused it into the body and watched as it replicated harmless versions of itself
+An AIDS virus genetically engineered to fight other AIDS viruses has worked better than expected, suppressing the virus and renewing the immune systems of a few patients, researchers report. 
+The study involved just five people but the surprising results offer new hope both for the field of gene therapy and for treating the fatal and incurable AIDS virus.
+But such an approach needs years more study, the researchers caution.
+"The goal of this phase I trial was safety and feasibility and the results established that," says Dr Carl June of the University of Pennsylvania School of Medicine, who led the study.
+"But the results also hint at something much more," he adds. 
+"It seemed to have a vaccine-like effect in that the immune system was better in most of the patients than when they enrolled. We are trying to study the mechanism." 
+HIV infects close to 40 million people worldwide and has killed 25 million. A cocktail of drugs can help control infection, but there is no cure and no vaccine.
+The drugs can cause severe side-effects in some patients and the virus can evolve resistance, so that patients have to move to new drug combinations.
+Gene therapy is a promising but troubled field of research based on the premise that altering genes can cure disease.
+It has cured only a few patients, and some have developed leukaemia as a consequence. One gene therapy volunteer died in 1999. 
+June's team tried a new gene therapy approach, first crippling the HIV virus, they report today in the Proceedings of the National Academy of Sciences.
+"The virus is gutted so that it only has half the size of the original or pathogenic virus," June says.
+Antisense approach
+The so-called envelope gene remains, and is reversed, a manipulation called antisense.
+The researchers then recruited five patients with HIV who were beginning to fail treatment. Their drugs no longer worked and the virus was beginning to damage their immune systems. 
+June's team removed the immune cells, CD4 T-cells, that HIV attacks. The researchers infected the CD4 cells in the lab with their newly engineered antisense HIV virus, then infused them back onto the patients.
+When HIV or any other virus infects a cell, it injects its own genetic material into the cell. The cell is turned into a virus factory, sometimes pumping out thousands of copies of a virus before it explodes.
+After the new antisense virus was infused, newly infected cells pumped out defective virus, June says. 
+"The virus particles that are released are, like, sterile. They are nonpathogenic," June says. 
+Safety first
+This test was meant only to show that the approach was safe, and three years later, none of the patients show ill effects. 
+The treatment appears to have helped restore the immune systems of four of the five patients, and the virus remains partly suppressed. 
+"We put back more [CD4 cells] than we took out. We don't know if that is why their immune system gets better, because there are more soldiers, or whether it got better because of better antiviral effects," June says. 
+The therapy is being developed by Gaithersburg, Maryland-based VIRxSYS Corp and the studies are partly paid for by the National Institute of Allergy and Infectious Diseases. 
+Phase II trials are under way in HIV patients who have disease well-controlled by drugs. June says it is not yet clear if the treatment could work only in infected patients, or might even be used as a preventive vaccine some day.
+
+The aircraft's 'belly' has been designed to improve lift
+Plans for a new generation of silent aircraft, designed to slash noise output while also cutting fuel consumption, have been unveiled by UK and US aeronautics experts.
+The single-wing aircraft would hold 250 passengers and use 25% less fuel than the current average, say its creators who hope to have it flying commercially by 2030.
+The Silent Aircraft Initiative (SAI) has since 2003 gathered some 40 researchers from the University of Cambridge and the Massachusetts Institute of Technology, as well as an array of aeronautics-linked firms.
+As well as cutting engine noise, the designers focused on adapting the structure of the aircraft, which is responsible for half of the noise a plane creates on landing.
+To do this they created a single flying wing, with the body of the aircraft also functioning to give lift.
+This allows a slower approach which reduces noise as well as improving fuel efficiency at cruising altitudes, the researchers say.
+The new plane also does away with flaps, a major source of noise, while the undercarriage has been simplified and its aerodynamics improved.
+The engines are mounted on the top of the aircraft, to screen much noise from the ground.
+Some backers of the project admit to having had doubts at first about its viability.
+"My first reaction on hearing of the Silent Aircraft Initiative was profound scepticism," says Dr John Green of Greener by Design, which promotes environmentally-friendly air transport options.
+"Three years on, I have to concede that the SAI has surpassed my expectations by quite a margin.  The team has produced a ... credible design that is predicted to meet the original target."
+
+There are concerns that a merger between two Sydney museums will eat up resources
+International researchers are so concerned about the proposed merger between the Australian and Powerhouse museums that they are urging the government to drop its plans.
+In letters to New South Wales arts minister Bob Debus obtained by ABC Science Online, they say a merger would jeopardise scientific research.
+The government wants to bring both museums under one board and integrate them "at a functional level", according to a letter Debus sent to the president of the Australian Museum Trust, Brian Sherman, in August.
+Professor Victor Springer, of the Smithsonian Institute's National Museum of Natural History, says such a move could jeopardise the Australian Museum's worldwide contribution to science.
+"I ask you with the most sincere and profound concern to ensure that neither the quantity nor the quality of the scientific research capacity at the Australian Museum suffers as a result of the proposed merger," he says.
+Others, including Professor Lee Fuiman, director of the University of Texas Marine Science Institute, and senior curator at the Royal Ontario Museum, Dr Richard Winterbottom, have also appealed for the government to drop the merger plans.
+"It appears to me that if this merger were to proceed, scientific research at the Australian Museum would be marginalised or might even disappear," Fuiman writes.
+Professor Richard Rosenblatt, of the Scripps Institution of Oceanography at the University of California San Diego, writes that he is concerned "the proposed merger ... will result in a loss of scientific research capacity and positions".
+Australian scientists also concerned
+Scientists from the University of Sydney, University of Wollongong and the Australian Marine Sciences Association have also written to express concern, as has a delegation of prominent members of the science community that is understood to have presented the government with a petition last week.
+Their concerns are understood to include the fact that the Powerhouse and Australian museums have a separate history, manage different collections and have diverse research priorities.
+In a letter to scientists, Debus says the government is doing a feasibility study to examine the "benefits, costs and issues" associated with combining the boards of the two museums.
+He says the need to protect their expertise is a paramount concern and that the government is taking a "careful and considered approach to this matter".
+But the Public Service Association of New South Wales, which represents some of the 550 staff at both museums, has described the move as a cost-cutting exercise and fait accompli that will go ahead regardless of the outcome of the study.
+Director of the Australian Museum, Frank Howarth, was not available to comment.
+Scorpion fish and tiny vertebrates
+Among research at the Australian Museum has been the discovery of a new species of scorpion fish in Sydney Harbour and what could be the world's smallest vertebrate, the stout infantfish (Schindleria brevipinguis), in the Great Barrier Reef.
+A staff member at the Australian Museum, speaking on the condition of anonymity, says there are fears that research will be cut altogether or at least downgraded under an amalgamation.
+"The Powerhouse Museum doesn't have a scientific research component like we do and it would be easy to say this doesn't fit  into the new model so let's get rid of [research] all together," he says.
+"There's a school of thought that says this stuff should be at universities."
+He says five of the museum's 20 designated research positions are vacant and are almost certain not to be renewed in the event of a merger.
+Staff have already begun looking elsewhere because of uncertainty about the museum's future, he says.
+One scientist, a world leader in his field, is understood to have already accepted a job at the Natural History Museum in London.
+Report due
+Dr Des Griffin, who resigned in 1998 after 22 years as director of the Australian Museum, says the plan to bring the two bodies under a new, single governing body will have little benefit for either the museums or the public.
+He says all areas, including scientific research, social history and collection conservation, are likely to be hit.
+A steering committee consisting of departmental and museum representatives is due to report to the government on the amalgamation plan on 22 November.
+The report comes amid uncertainty about how the amalgamation will proceed when Debus, who recently announced his retirement, quits parliament at the state election in  March.
+
+The solar flare was hundreds of thousands times more powerful than this one, a typical solar flare from our Sun seen in 2005. The II Pegasi flare was too distant to image in detail
+The most colossal x-ray flare ever detected has been caught in the act of zapping its solar system with planet-killing radiation.
+The star is II Pegasi in the constellation Pegasus, about 135 light-years from Earth. 
+That means the explosive flare seen by the NASA Swift satellite, designed to detect much more distant and powerful gamma-ray bursts, took place around the year 1871. Light from the event is only now reaching Earth.
+The x-ray flare is the first-ever detected beyond our own Sun that bears a striking resemblance to the much smaller 'x-class' flares generated occasionally by our own Sun.
+"It's a hundred thousand times more powerful than the largest solar flares ever recorded," says astronomer Dr Steven Drake of NASA's Goddard Space Flight Center.
+Despite being far more powerful, it looks like it was created in the same way, he says.
+It starts with a tangle of magnetic field lines on the surface of a star that short-circuits. When that happens, atomic particles are accelerated to speeds only seen on Earth in high-tech particle accelerators.
+The accelerated particles can emit gamma rays, which is what caught the Swift satellite's attention in the first place.
+When the satellite turned to face II Pegasi, it took aim with its x-ray detector and caught the hour-long eruption of x-rays.
+Violent eruption
+The x-rays were created as material violently erupted from the star and then arched back down and slammed back onto its surface.
+By comparison, x-ray flares on the Sun last only second or minutes, at most.
+"It's certainly one of the biggest ever seen," says Drake about the II Pegasi flare. It's the hands-down winner in terms of those seen in 'soft' x-rays, which are the rays just beyond the wavelength of extreme ultraviolet light.
+Drake is a co-author on a paper on the flare that is being presented by the University of Maryland's Dr Rachel Osten at a meeting in Pasadena this week.
+Flaming star
+What's less surprising about the flare, however, is that it originated from II Pegasi, says Pennsylvania State University astrophysicist Professor Eric Feigelson.
+"It's known to be one of the most flaring stars," says Feigelson. If he had been asked to guess which nearby stars were capable of belting out such a flare, II Pegasi would have been among his top 10, he says.
+Despite being a middle-aged star that ought to be past this sort of wild and violent behaviour, II Pegasi is part of a tightly-bound two-star system in which the stars are roaring around each other, generating powerful tidal forces that keep II Pegasi riled up.
+Fortunately our own Sun is relatively quiet and stable, with x-ray flares that are unable to penetrate Earth's atmosphere.
+
+The bill lifts a ban on therapeutic cloning, allowing the creation of human embryos for research
+Australian scientists will not be allowed to use animal eggs to create embryonic stem cells under a bill passed by the Senate this week.
+For now, this rules out creating 'hybrid' human-animal cells for human disease research in Australia.
+Despite this, top stem cell researchers have welcomed the bill, which lifts a ban on therapeutic cloning by allowing the creation of human embryos specifically for research.
+The bill, which will now go before the House of Representatives, allows a process called somatic cell nuclear transfer (SCNT).
+This involves removing the nucleus from an egg and replacing it with one from a non-reproductive body cell, of a patient for example, to produce an embryo, the same method used to produce Dolly the sheep.
+Under the bill, narrowly passed by two votes in the Senate, SCNT embryos will not be implanted, but used to produce embryonic stem cells and then destroyed after 14 days.
+The Lockhart report late last year called for amendments to Australian cloning law to allow therapeutic cloning using SCNT, and it recommended that both human and animal eggs be permitted for use in research.
+But the bill passed this week rules out the use of an animal egg as a host for a human nucleus.
+It comes at the same time that researchers in the UK are requesting permission to use cow eggs fused with human material for research on Parkinson's, stroke and Alzheimer's.
+Lockhart committee member, Professor Loane Skene from the University of Melbourne, says the committee recommended that animal eggs be used in research to reduce the demand on women for eggs.
+"It's an invasive procedure for a woman to donate an egg and the eggs are very precious," says Skene. "So we thought it would be better to allow another source of eggs, namely animal eggs, to be used."
+"It was never envisaged that any stem cells that were produced from this would go into treatments for people."
+Bill welcomed despite animal egg ban
+Despite the ban on animal eggs, leading stem cell researchers have welcomed the bill.
+Professor Bernie Tuch of the University of New South Wales in Sydney says the decision is as momentous as the assassination of US president John F Kennedy.
+"Reason has prevailed," says Tuch, who is quietly confident the bill will pass the House of Representatives.
+Professor Alan Trounson of Monash University in Melbourne says the decision is consistent with public opinion show by surveys to be 60-80% in favour of therapeutic cloning.
+"I'm very pleased," he says.
+But Trounson says the decision to ban the use of animal eggs will limit research.
+He says research using animal eggs helps understand the factors in cells that are responsible for reprogramming it to become pluripotent, capable of turning into many other kinds of cells.
+And he says the hope is that these factors could one day be identified and made synthetically, thus eliminating the need for embryos altogether in stem cell research.
+But he says thousands of eggs are required to sequence and identify the factors and there are just not enough human eggs for this. 
+"You can't get thousands of human eggs to extract the factors," he says.
+Tuch is less concerned about a shortage of eggs.
+He says one possible source will be the 240 women a year that have their ovaries removed because a genetic predisposition to ovarian cancer.
+Trading eggs?
+Trounson says eggs will be gathered internationally for research to find suitable embryonic stem cell lines.
+A sociologist who studies the global trade in human and animal tissue, Peta Cook of the Queensland University of Technology in Brisbane says it's this international context that needs to be considered when it comes to the pressures on women to sell their eggs.
+While this is illegal in Australia, Cook says there is a booming international trade in body parts.
+"If I need a kidney, I can travel to Pakistan or India and receive one from a live donor," she says. "It is close to an on-demand system."
+Similarly, women in Eastern Europe have had their eggs taken illicitly and sold by health-care professionals, says Cook.
+She says that in the US a woman can sell her eggs for up to US$10,000 and this is very tempting to poor university students and such financial incentives can undermine informed consent and autonomous decision-making.
+
+Climate changes in Greenland over the past 150,000 years are reflected in Antarctica, scientists show. They say the link is a conveyor belt of ocean currents that links north and south
+Antarctica and Greenland may be at opposite ends of the planet but their climate systems appear to be linked by a remarkable ocean current, a study shows.
+The results, published today in the journal Nature, suggest that Antarctica's ice could eventually start to melt because of localised warming in the far North Atlantic. 
+The evidence comes from a 2500 metre ice core, drilled by European scientists at Dronning Maud Land, on the part of Antarctica that faces the South Atlantic.
+With its compacted layers of ice and telltale concentrations of methane in trapped air bubbles, the core yields a picture of snowfall and atmospheric temperatures going back 150,000 years. 
+Even better than that, it can be matched with cores of similar amplitude drilled in the Greenland icesheet.
+Put together, the cores provide the first solid evidence to back a theory that millennial scale climate changes that have unfolded in the far north and south of the Atlantic are not isolated, local events, but linked. 
+The glacial climate in the Northern Atlantic can swing extraordinarily rapidly, with temperatures rising by 8-16&deg;C within the space of a few decades at the end of each Ice Age and falling back, albeit more slowly, when the next Ice Age beckons.
+Antarctica, though, has far smaller temperature shifts, of between 1-3&deg;C, and these unfold over millennia.
+But the two sets of ice cores point to what the European Project for Ice Coring in Antarctica scientists describe as a bipolar seesaw
+In short, what happens at one end of the Atlantic has a huge effect on the other, although at different time scales and in different ways. 
+The cause appears to be a conveyor-belt system of ocean flows.
+On the conveyor belt 
+Relative heat from the Southern Ocean around Antarctica is picked up by a complex system called the meridional overturning circulation (MOC), of which the Gulf Stream is the best-known component. 
+The MOC channels warm surface water up to the North Atlantic, coincidentally enabling countries in northwestern Europe to have a balmy climate despite their northerly latitude. 
+When this warm water reaches the far north, it cools and sinks, and the MOC sends it back south, back down towards Antarctica, at depths far below the ocean's surface. 
+"Our data shows that the degree of warming in the south is linearly related to the duration of cold periods in the North Atlantic," says lead author Dr Hubertus Fischer of Germany's Alfred Wegener Institute for Polar and Marine Research in Bremerhaven.
+Understanding this link also sheds light on what the researchers say is a troubling aspect about human-induced climate change: the fate of Antarctica, where the world's biggest store of frozen water is held.
+"Today, Antarctica is still a reservoir of cold. We don't see any contribution to global sea-level change because of Antarctica, it's not melting yet. In fact there has been more precipitation and some models suggest that Antarctica actually will grow a little," Fischer says. 
+That reassuring scenario could change if, as some studies are now tentatively suggesting, the MOC is beginning to falter, says Fischer. 
+The causes for this slowing of the Atlantic conveyor belt could be a run-off of cold water from melting Siberian permafrost or the Greenland icesheet, triggered by rising atmospheric temperatures.
+But any disruption would lead to a build-up of warmer water off Antarctica, according to the conveyor-belt theory.
+"If the thermohaline [ocean convection] circulation in the Atlantic slows down just a little, it would cause a warming in the Southern Ocean," Fischer says. 
+"And if you have warming around Antarctica, at a certain point, the fringes of Antarctica will even warm over the melting point. Then we could start to see melting at the borders and run-off and that would contribute to sea-level rise."
+
+Transplanted photoreceptor cell shown in green against a background of the host's retina
+Scientists have restored the sight of blind mice by transplanting light-sensitive cells into their eyes, a new study shows.
+The mice suffered from eye damage called photoreceptor loss, which occurs in macular degeneration, the leading cause of sight loss in the elderly, and other eye disorders.
+But instead of using stem cells, which could form into any cell type, the scientists transplanted cells that had reached a later stage of development towards becoming photoreceptor cells.
+The international team publishes its results today in the journal Nature.
+"We have shown for the first time that it is possible to transplant photoreceptors," says lead author Dr Robert MacLaren, a scientist and eye surgeon at Moorfields Eye Hospital in London.
+"These cells are lost in some of the more common causes of blindness," he adds.
+The scientists believe further research could lead to the first human retinal cell transplants for people with blinding diseases within a decade.
+Photoreceptors are specialised light sensitive cells that line the back of the eye and are essential for sight. In eye diseases such as macular degeneration the cells are destroyed.
+Previous studies that had used stem cells, master cells that have the potential to become any type of cell in the body, had failed because the cells did not form into photoreceptors.
+Researchers had thought that the mature retina, the part of the eye that senses light and forms images, did not have the capacity for repair.
+MacLaren and his collaborators showed using precursor cells that are already programmed to become photoreceptors, but are not quite there yet, was the key to successful transplantation.
+"We have taken them out of the donor retina and transplanted them into a host retina extremely quickly at that precise point in time and with minimal trauma to the surrounding tissue," MacLaren explains. 
+The mice had eye diseases caused by genetic defects. 
+Scientists have recently found cells on the margin of the retina in humans that have stem-cell like properties and could potentially be grown in the lab to become photoreceptor precursor cells for treatment.
+"Rather than focusing on stem cells we believed that if we could understand how cells develop and become photoreceptors ... our transplantation efforts would meet with greater success," says Professor Anand Swaroop, of the University of Michigan Medical School and a co-author of the study.
+"This technique gives us new insights in repairing damage to the retina and possibly other parts of the central nervous system," he adds.
+
+Online searches can help doctors keep up to date with an increasing pool of medical research
+It's not just patients who are frantically plugging their symptoms into Google to see what disease they might have. Australian researchers say doctors are doing it too.
+Dr Hangwi Tang and Dr Jennifer Ng of the Princess Alexandra Hospital in Brisbane report their findings today online in the British Medical Journal.
+Tang says the study was driven by personal curiosity after noticing how patients and doctors alike were using Google to diagnose difficult cases.
+In one example he had a patient whose father used the search engine to correctly diagnose that his son had the rare circulatory condition Paget-von Schrötter syndrome.
+Tang and Ng selected 26 difficult cases presented in the New England Journal of Medicine, including Cushing's syndrome, Creutzfeldt-Jakob disease, encephalitis and cirrhosis.
+They then plugged the symptoms of each case into the search engine to come up with a diagnosis.
+When these diagnoses were compared with the correct published diagnoses, the researchers found that Google got it right 58% of the time.
+They say an online search is likely to be more effective at helping to diagnose conditions with unique symptoms that can be used as search terms.
+Tang says part of the challenge in using Google is to be able to efficiently sift through the many pages of links that you get from an online search.
+And he thinks that doctors are better placed than patients at doing this because they are better at selecting relevant links.
+"I don't think Google can replace doctors, in other words," says Tang.
+Millions of facts
+Doctors have been estimated to carry two million facts in their heads to help them to diagnose disease, the researchers say.
+But search engines allow them to get quick access to an ever increasing medical knowledge base that might be impossible to hold in their head.
+Google in particular gives access to more than three billion articles, they say, with Google Scholar restricting searches to peer reviewed articles.
+Tang says while there are a number of other search engines that clinicians can use, they often prefer Google because it is so easy to use and freely available.
+Other studies
+Professor Johanna Westbrook of the Centre for Health Informatics in Sydney says the findings are consistent with her own.
+Her team looked at how specialised search engines could help clinicians to both diagnose and treat patients, using the best available evidence.
+The study found clinicians were 21% more likely to give the correct answers when they used online search engines.
+Interestingly though, a few clinicians got the wrong answers using the search engines, although they got the right answers without them.
+Westbrook says this underscores the importance of learning how to interpret complex evidence.
+Another interesting finding was that clinical nurse consultants using the search engines were just as accurate as doctors.
+Westbrook says this suggests search engines might help such nurses to diagnose and treat patients in rural areas where there are fewer doctors.
+"[An online search engine is] available 24 hours a day," she says. "Whereas you can't get a clinician 24 hours a day. You can't get to a hospital library 24 hours a day."
+Westbrook says that while Google might be good for helping find information about diseases with unique symptoms, more sophisticated search engines would be required for more complex diseases.
+
+A gene type that governs brain size, which may have had a Neanderthal origin, exists in modern humans
+Neanderthals may have given the modern humans who replaced them a priceless gift, a gene that helped them develop superior brains, US researchers report.
+And the only way they could have provided that gift would have been by interbreeding, say the scientists. 
+Their study, published online in the Proceedings of the National Academy of Sciences this week, provides indirect evidence that modern Homo sapiens and Neanderthals interbred at some point when they lived side by side in Europe.
+"Finding evidence of mixing is not all that surprising. But our study demonstrates the possibility that interbreeding contributed advantageous variants into the human gene pool that subsequently spread," says Professor Bruce Lahn, a Howard Hughes Medical Institute researcher at the University of Chicago who led the study.
+Scientists have been debating whether Neanderthals, who died out about 35,000 years ago, ever bred with modern H. sapiens. Neanderthals are considered more primitive, with robust bones but a smaller intellects than modern humans.
+Lahn's team found a brain gene that appears to have entered the human lineage about 1.1 million years ago.
+It has a modern form, or allele, that appeared about 37,000 years ago, right before Neanderthals became extinct.
+"The gene microcephalin (MCPH1) regulates brain size during development and has experienced positive selection in the lineage leading to Homo sapiens," the researchers write. 
+Positive selection means the gene conferred some sort of advantage, so that people who had it were more likely to have descendants than people who did not.
+A common variant
+Lahn's team estimate that 70% of all living humans have this type D variant of the gene.
+"By no means do these findings constitute definitive proof that a Neanderthal was the source of the original copy of the D allele. However, our evidence shows that it is one of the best candidates," Lahn says. 
+The researchers reached their conclusions by doing a statistical analysis of the DNA sequence of microcephalin, which is known to play a role in regulating brain size in humans.
+Mutations in the human gene cause development of a much smaller brain, a condition called microcephaly. 
+By tracking smaller, more regular mutations, the researchers looked at DNA's genetic clock and dated the original genetic variant to 37,000 years ago. 
+They note that this D allele is very common in Europe, where Neanderthals lived, and more rare in Africa, where they did not.
+What's the advantage?
+Lahn says it is not yet clear what advantage the D allele gives the human brain.
+"The D alleles may not even change brain size; they may only make the brain a bit more efficient if it indeed affects brain function," he says. 
+Now his team is looking for evidence of Neanderthal origin for other human genes.
+
+Each of these spawning sea urchins share more than 7000 genes with humans
+Scientists who have sequenced the genome of the sea urchin say these brainless and limbless invertebrates are surprisingly similar to humans.
+They found that the California purple sea urchin (Strongylocentrotus purpuratus) genome has 23,300 genes.
+And it shares 7077 of them with humans.
+The genetic ties are far closer than scientists expect and make the sea urchin a closer genetic cousin of humans than the worm or fruit fly, according to the study in today's issue of the journal Science. 
+"Nobody would've predicted that sea urchins have such a robust gene set for visual perception," says Gary Wessel, a Brown University biology professor and member of the Sea Urchin Genome Sequencing Consortium.
+"I've been looking at these organisms for 31 years, and now I know they were looking back at me." 
+Among other surprises from the project were that researchers found sea urchins have the most sophisticated innate immune system of any animal studied to date.
+They say this may be one reason they live 100 years or more. 
+Sea urchins also carry genes associated with human diseases such as muscular dystrophy and Huntington's. 
+The creatures also have genes associated with taste, smell, hearing and balance, the study found.
+
+Picture books help 2-3 year olds learn about the world. But are some books better than others?
+Toddlers can re-enact what they see, hear and learn from picture books, new research shows.
+The finding suggests that picture books may play a much greater role than simply entertaining toddlers and may help them understand the world.
+Researchers from the University of Queensland and the University of Virginia publish their findings in the latest issue of the journal Developmental Psychology.
+Researchers know that picture books can help 4-5 year old preschoolers with a range of literary and 'life' skills.
+But it is harder to assess what 2-3 year olds learn simply because they don't have the language skills to tell us.
+"So what we did in our study was to let toddlers show us what they know using a re-enactment, or imitation paradigm," says Australian author Dr Gabrielle Simcock, a postdoctoral fellow at the University of Queensland.
+Researchers read toddlers a picture book that described how to make a toy rattle.
+They then asked the toddlers to make a rattle using the objects supplied: a green wooden ball, a stick attached to a plastic lid and a clear plastic jar.
+Some 36 children in each of three age groups (18 months, 24 months and 30 months) were read either a picture book featuring colour photographs of a rattle being made, a picture book with coloured pencil drawings of a rattle being made, or not read a book at all.
+Overall, children across all groups shown the colour photograph book were more successful in their attempts to make a rattle than those shown a colour drawing book or no book.
+Toddlers aged 24 months and 30 months did equally well with both versions of the book.
+But the 18 month toddlers shown the colour photograph book did much better than those shown the colour drawing book.
+"The 18 month children needed the representation in the book to be highly realistic and to match very closely to the real world before they could understand, while the older children were much more flexible in their ability to use the pictures."
+The control group was least likely to be able to make the rattle.
+Simcock says the findings are exciting, but don't mean that parents should only read their children only picture books with real-life photographs.
+"I think it's through cumulative exposure to a wide range of different types of books and illustrations that children begin to abstract that the pictures in the books can represent real world things," she says.
+"And not all books are informative about the real world; often they might be animals talking and doing things ... [simply to] entertain."
+
+The idea is you would be able to recharge your laptop without plugging it in
+You may one day be able to recharge your laptop or mobile phone without having to plug it into the wall, says a US physicist.
+But others say there are many hurdles before such transfer of energy means we can say goodbye to wires.
+Assistant Professor Marin Soljacic, of Massachusetts Institute of Technology, will present his team's work at the American Institute of Physics forum in San Francisco this week.
+Today's wireless transfer of energy, such as the transfer of light energy from the Sun for solar power or the transfer of microwaves from transmitters for communication, involve relatively low levels of energy.
+But recharging devices like laptops requires a much higher level of energy. And if this was routinely zapped through the air it could 'fry' any living organisms that get in the way.
+But Soljacic says he's found a way of transmitting energy so that only the devices that it is recharging will pick it up, so it will not affect humans.
+Instead of using traditional radiation, he wants to use the part of the electromagnetic field that is 'non-radiative'.
+He says devices can be tuned to the frequency of this field and thus act as a sink for all the energy the transmitter gives out.
+Soljacic says this would prevent energy radiating out to areas it doesn't need to go to providing an efficient and safe method of wireless energy transfer.
+"The team calculates that an object the size of a laptop could be recharged within a few metres of the power source," he says. "Placing one source in each room could provide coverage throughout your home."
+Soljacic also thinks the technology could be used to power freely roaming robots in a factory.
+Finding a 'magic' frequency
+But Australian physicists, yet to see the full details of Soljacic's work, are sceptical of his claims.
+They say the challenge is finding a 'magic' frequency that doesn't also affect with living organisms and thus pose possible health risks.
+"You would be reintroducing all the problems that we went through with mobile phones," says Dr Geoff Anstis of the University of Technology, Sydney, referring to the uncertainty surrounding any long-term health effects of using mobiles.
+"And it wouldn't be until a couple of decades that you may be happy that there isn't a significant problem."
+His colleague Professor Geoff Smith agrees and says there are also technical challenges to keeping the devices tuned with the transmitters, thus preventing the general release of stray energy.
+"I think this is nice physics but there's a way to go before it would be possible," says Smith.
+He says any changes in the surrounding environment could "de-tune" the system and stop the safe and efficient transfer of power.
+Electrical engineer, Dr Trevor Bird of CSIRO's ICT Centre says attempts so far to develop wireless power transfer have not been very successful.
+He agrees that safety and technical barriers to wireless power systems are huge and would like further details on Soljacic's proposal.
+Bird also says that, depending on the frequency of the field, the antenna on the device being recharged may have to be very large.
+
+Eye of the storm
+Saturn has cooked up a sizeable storm that scientists say is the first in the solar system besides Earth to feature a hurricane-like eye and well formed towers of clouds.
+The storm is smaller than the famed Great Red Spot churning away on Saturn's giant neighbour Jupiter, but is still formidable.
+It sprawls for about two-thirds the diameter of Earth across Saturn's southern pole.
+"It looks like a hurricane, but it doesn't behave like a hurricane," says Dr Andrew Ingersoll, a Cassini scientist at the California Institute of Technology in Pasadena.
+The NASA Cassini spacecraft spent three hours on 11 October observing the beast and clocked its winds at 550 kilometres per hour, twice as strong as Hurricane Katrina at its peak. 
+The spacecraft also imaged a shadow cast by clouds stacked above and ringed around the south pole, as well as two spiral arms of clouds protruding from the central ring.
+Scientists estimate the tower of clouds spans 30-75 kilometres above the clouds in the centre. That's between two and five times taller than the clouds that surround the eye of a hurricane on Earth.
+The Saturn storm can grow much taller because the planet's hydrogen-helium atmosphere is much less dense than Earth's at comparable pressures.
+Also unlike hurricanes on Earth, the storm is not moving around, but appears locked at Saturn's south pole.
+And with a temperature of around minus 170&deg;C, there is no ocean, nor warm tropical water to pump its strength.
+At the base of the eye, scientists can discern, but not explain, dark clouds. They do know Saturn's south pole is warmer than the rest of the planet.
+"The winds decrease with height and the atmosphere is sinking, compressing and heating over the [planet's] south pole," says Dr Richard Achterberg of NASA's Goddard Spaceflight Center.
+Additional observations are planned as the seasons change on Saturn and the south pole transitions from summer to autumn.
+"Whatever it is, we're going to focus on the eye of this storm and find out why it's there," Ingersoll says.
+
+Dr Richard Helmer plays air guitar
+It could make an ideal Christmas present in years to come. Australian scientists have built a t-shirt that lets you play 'air guitar' for real.
+Dr Richard Helmer and his CSIRO colleagues stitched wearable sensors into an ordinary long sleeved t-shirt to create a prototype of what they're calling a 'wearable instrument shirt'.
+Simply by moving one arm to choose chords and the other to strum some imaginary strings, home rockers wearing the shirt could make actual music.
+The tunes come courtesy of a pair of small but resilient sensors placed in the elbows of the t-shirt.
+The sensors bend when you move your arm, sending wireless signals to custom software that turns them into audio samples.
+"When you move your arm it bends a filament in the sensor, which changes its resistance," says Helmer. "It's a bit like a volume control."
+One of the smart things about the technology is the sturdiness of the interface, Helmer says.
+The materials can all stand up to ultraviolet light, moisture and movement, so working up a sweat is less likely to cause problems.
+"It allows you to jump around and the sound generated is just like an original mp3," he says.
+The shirt is part of a wider CSIRO program on intelligent fabrics that aims to tackle more serious applications like health monitoring or 3D computer interfaces.
+So why design an air guitar?
+"I thought we needed to do something that was a little less serious that people could have fun with," Helmer says.
+In the meantime, the researchers aren't deaf to the possibility that their experiment could have commercial potential.
+"It depends on how much people want it," Helmer says.
+The price might start out relatively high, but over a year or two could drop down to "Christmas present level", the researcher says.
+At this stage, no-one knows exactly how much it might retail for, but it would probably be in the hundreds of dollars, Helmer suggests.
+A small price to pay, perhaps, for turning rock star fantasies into reality.
+
+Seabirds and migratory birds are early responders to changes in climate, according to a new report
+Nearly three quarters of all bird species in northeast Australia and more than a third in Europe could become extinct unless efforts to stop global warming are stepped up, a report says. 
+Up to 72% of bird species in northeastern Australia and 38% of bird species in Europe could disappear completely if the planet's temperature continues to rise, according to the international environmental group WWF.
+"This report finds certain bird groups, such as seabirds and migratory birds, to be early, very sensitive responders to current levels of climate change," says WWF's director of climate change policy Hans Verolme. 
+"Large-scale bird extinctions may occur sooner than we thought," he says in Bird species and climate change: the global status report, released today on the sidelines of the UN climate change conference in Nairobi.
+"If high rates of extinction are to be avoided, rapid and significant greenhouse gas emissions cuts must be made," WWF says. 
+Rising sea levels, changes in vegetation and altered temperatures are among the effects of climate change linked to greenhouse gas emissions that impact negatively on bird species worldwide, it says. 
+In the Great Plains of North America, where up to 80% of the continent's ducks come to breed, three quarters may face extinction because of adverse global warming-related changes to their habitat, the report says.
+While the effects would be most significant if the Earth's surface temperature rises 2&deg;C above its pre-industrial level - it is currently 0.8&deg;C above - some birds are already feeling the heat.
+The penguin population of the Galapagos Islands has decreased by half since the early 1970s, due to starvation and an inability to reproduce resulting from the effects of the El Ni&ntilde;o climate pattern.
+While migratory, mountain, island, wetland, Artic, Antarctic and seabirds are all at high risk from climate change, other species that are able to move easily to new habitats will not be as badly effected, it says.
+Scientists also point out that existing conservation programs do not provide sufficient protection, as bird species often shift into unprotected zones, the report says.
+
+Psychologists says the secret of good batting is being able to anticipate the intent of the bowler
+The best batsmen can predict the sort of ball a bowler's going to deliver before it even leaves his hands, a new study into the psychology of cricket shows.
+Less successful batsmen aren't so highly attuned to subtle visual clues, reports Dr Sean Müller of RMIT University in the latest issue of the Quarterly Journal of Experimental Psychology.
+Müller's study shows that a top batsman can predict how a ball will swing and where it will bounce well before it's airborne.
+"[Experienced players] can pick up ... cues that the intermediate and novice players don't or aren't sensitive to," he says.
+A less skilled batsman can only make these judgements once the ball is in flight, giving him less time to get in the right position.
+Time is critical as it can take just half a second from when the ball leaves the bowler's hand to it reaching the crease.
+Video simulations
+Müller put members of the Australian cricket team through a number of tests, which were also repeated on intermediate and novice cricket players.
+Participants included former captain Steve Waugh and Ricky Ponting, who'll skipper Australia when it faces England in the first Ashes Test in Brisbane next week.
+In one test, the subjects were shown a video of a bowler running up, from the batsman's point of view.
+The video was stopped at various stages of the run-up and delivery, and subjects were required to make a prediction about the ball based on this limited information.
+They were also shown a video with various parts of the bowler's body blocked out, for example, with just a hand.
+"We occluded all of the bowler ... so you'd see this little hand running in all the way from the start and then it'll stop, the screen will go black at the point of ball release," he says.
+Experiments were also carried out on the field with batsmen wearing goggles that blacked out parts of the bowler's body.
+Inherent or learnt skill?
+Müller says it appears that movement-related cue-reading is subconscious, because even the batsmen who were best at anticipating the bowler's intention couldn't specify why.
+Müller says while some people may be naturally more attuned to picking up visual cues, it's likely this can be taught and learned.
+"You need to be exposed to different types of bowlers, different ways the ball spins, in order to learn the relationship between a cue and what will actually happen," he says.
+"It takes time to develop [this skill] and practice is needed."
+Can we improve batting?
+His next study will look at whether videos and goggles can be used to refine predictive ability and improve batting.
+"If a player is going through a slump you could use this method to pick up if they need remedial work in picking up particular cues," he says.
+The study has other practical implications.
+Müller says honing our skills of predictive judgement can make us better drivers or help us cross roads more safely.
+He says humans probably developed predictive judgement as an evolutionary skill to help avoid injury or attack.
+Müller was a PhD student at the University of Queensland when he conducted the research.
+
+This false colour image reveals a large dust cloud in the globular cluster M15 (in red), the first time that dust has been seen there
+Dawdling old stars, and not just the spectacular explosions of massive supernovae, may create much of the cosmic dust that builds generations of new stars and planets like our own, say astronomers.
+The NASA Spitzer Space Telescope has spied loads of dust in what was expected to be a dust-free stellar cluster of old stars, known as M15, in the distant Pegasus cluster.
+The surprising observations are pointing to a new way of looking at how the galactic star-making factories work.
+It also may help explain why there's so much more cosmic dust than can be accounted for by supernovae alone.
+"[It] was very surprising to see the dust there," says Chick Woodward, an astronomy professor at the University of Minnesota.
+Woodward and graduate student Martha Boyer led a study of the dust, which appears in the Astrophysical Journal.
+"In a sense it's a very simple observation," but one that had never been made so clearly before, says astronomer Professor Christopher Sneden of the University of Texas at Austin.
+Now there is no doubt that the dust is coming from the old stars. That could help balance the galactic dust equation.
+But before the researchers can even get to that, they need to explain a more fundamental mystery of M15's dust, says Woodward.
+Lots of dust
+According to the accepted theory, cosmic dust needs to be seeded by heavier elements like silicon, oxygen and carbon, which tend to be products of bigger, short-lived stars.
+But M15's big old stars are poor in heavy elements, and there's still lots of dust.
+"How do we form dust when we don't have the metals around to condense them?" says Woodward. Astronomers call all elements heavier than hydrogen and helium 'metals'.
+The fact that dust could be forming in space without metals could mean astronomers may have to revise their basic theories on where and out of what sort of dust newer stars and planets form.
+As for how much dust there ultimately is in the galaxy, for decades astronomers figured the dustiest places are where stars are forming as it's cosmic dust that makes stars in the first place.
+They also suspected that aged stars like those in M15 lose mass to space, but had not witnessed it taking the form of dust until now.
+One reason the dust from old stars has been elusive, says Woodward, is that the stars are in clusters that formed at the same time as the Milky Way, 12.5 billion years ago.
+That's an awful lot of time for the clusters to bob up and down like a dolphin through the galactic plane.
+Spring cleaning the cosmos
+On each pass the clusters probably get a good scouring, a sort of spring clean in which the galactic wind clears away the dust.
+"[The periodic cleaning] helps explain why people haven't seen it in the past," says Sneden of the dust around old stars.
+One of the next steps, says Sneden, will be to look for more cases like M15, just to make sure it's not a fluke.
+"I'd like to know how common this is," he says.
+
+Films not only depict environmental concerns, they can contribute to them, according to a new report
+Scientists say Hollywood is responsible for creating an unwanted special effect in the skies above Los Angeles: pollution.
+A study by the University of California Los Angeles (UCLA) Institute of the Environment says the film industry is responsible for sending 140,000 tonnes of pollutants into the atmosphere every year. 
+Ozone and diesel emissions from trucks and generators used on movie sets as well as pyrotechnic explosions for special effects contribute to the layer of smog that hangs over Los Angeles. 
+"Many industries are moving toward more environmentally sustainable operations, and it's important that we monitor their progress," says institute director and law professor Mary Nichols. 
+Nichols says researchers note that although several studios and production companies are taking steps to minimise damage, the industry's lack of a unified environmental strategy is a barrier to improvement. 
+Two UCLA professors who conducted an analysis as part of the study conclude that Hollywood could be doing more, the report says. 
+"Our overall impression is that, with a few notable and inspiring exceptions, environmental considerations are not high on the agenda in the film and television industry, and that more could be done within the industry to foster environmentally friendly approaches," the professors say.
+The researchers cite the example of the makers of The Day After Tomorrow, who paid for a US$200,000 (A$260,000) package of environmental measures to offset damage caused by vehicles used in the 2004 blockbuster. 
+The makers of the last two Matrix films were also praised for arranging for more than 97% of set materials to be recycled.
+The study found the problem is attributable to the transient nature of production companies.
+"The degree to which work is controlled by short-lived ever-changing production companies ... [makes] it difficult to institutionalise best practices," it says.
+Business groups warn against using the report to crack down on the film and television industry, which generates around US$29 billion a year in combined revenues and employs around 252,000 people.
+
+The protein soup that makes up semen can trigger serious allergic reactions in some women
+Women can become allergic to their partners or other men, according to new research presented this week at a US conference.
+The culprit is semen, reports Dr David Resnick, acting director of the Division of Allergy at the New York Presbyterian Hospital.
+His research is due to be presented at the annual meeting of the American College of Allergy, Asthma and Immunology in Philadelphia.
+It isn't sperm but its accompanying proteins that can cause an allergic response, a phenomenon that allergy experts are recognising more often, he says.
+While there have been no reported deaths from an allergic response to semen, some women may require hospitalisation after experiencing difficulty breathing, hives and swelling.
+Less severe cases may result in itching, burning and swelling after intercourse. 
+More women may have the reaction than are aware of it, says Resnick. 
+"Some women think there's another problem [such as an infection or condom allergy]," Resnick says.
+"[But] in one survey, out of 1073 women who sought related information from a researcher, approximately 13% were determined to have a semen allergy."
+Sufferers, Resnick explains, produce an antibody that recognises the proteins in a partner's semen.
+The antibody triggers a powerful immune response, similar in mild cases to hay fever. Some women are only allergic to the semen of a certain partner, but others react to multiple men.
+Other allergens can be transmitted through the seminal fluid.
+These include medications such as penicillin, and even some foods and beverages, such as walnuts and soft drinks. Women with other allergies tend to be more prone to semen allergies.
+What can we do about it?
+Two basic types of treatment are available. The first is similar to standard allergy treatments that expose a sufferer to the allergen in diluted doses. 
+The second involves removing other proteins known to sometimes interfere with the desensitisation process from the semen plasma, and then injecting a small amount of the processed semen at regular intervals.
+In both cases, frequent sexual contact is needed after the treatment.
+"We actually had one case where the male spouse was unable to engage in such frequent intercourse, so his wife developed the allergy again," says Resnick. 
+Jonathan Bernstein, a professor of medicine at the University of Cincinnati, and one of the world's leading experts on semen allergies, says he agrees with Resnick.
+But he believes that the processed semen, though a more expensive treatment, would be more effective.
+Bernstein also believes the allergy is probably underreported.
+"It may not be as rare as people think," he says. "The allergy may go unrecognised, yet it can have a significant effect on relationships."
+
+Comets may have caused giant tsunamis much more recently, and much more frequently, than anyone thinks
+Enormous comets may have often bombarded our oceans causing tsunamis that dwarf ones seen today, says a small group of scientists.
+But most critics are yet to be convinced there's evidence to back claims about such recent, frequent mega-impacts.
+Conventional wisdom has it that the Earth suffers such violent hits from space only twice every million years.
+But scientists including Australian geomorphologist Associate Professor Ted Bryant of the University of Wollongong have been studying what they say is evidence of massive objects slamming into the Earth's oceans as recently as 500 years ago.
+They say these kilometre-wide objects are likely to have been comets.
+And Bryant says there have been up to 10 such impacts in the past 10,000 years, based on research with others, including Assistant Professor Dallas Abbott from the Lamont-Doherty Earth Observatory at Columbia University.
+Bryant says these would have caused mega-tsunamis 10 times bigger than the 2004 Asian tsunami, one of the largest earthquake-generated tsunamis the world has ever seen.
+"Aceh was a dimple compared to what we're looking at," says Bryant, who is associate dean of science at the university. 
+Evidence from Google Earth
+Bryant used satellite images from Google Earth to identify inland dunes in the shape of arrowheads that he says are signs of mega-tsunamis.
+The tsunamis would have displaced marine deposits containing marine fossils, he says, dumping them inland as 'chevron' dunes.
+"We've found that chevrons are everywhere, everywhere around the world's coasts," he says.
+Abbot used sea surface altimetry, which measures the height of the sea surface to get an image of the seabed, to identify possible underwater craters, which could be evidence of the impact that caused the tsunamis.
+Bryant says Abbot also looked for melted material in cores from the seabed around the craters to confirm impacts caused them. 
+The chevrons and craters were linked by the direction the chevrons were pointing.
+For example, two chevrons identified 6 kilometres inland from the Gulf of Carpentaria in Australia both pointed north in the direction of two craters found in the Gulf of Carpentaria itself, says Bryant. 
+Dating of sediments to the north of the craters suggests the impact happened 1500 years ago, he says, and the well-preserved chevrons also date to around the same time. 
+Indian Ocean crater
+Bryant says chevrons about 4800 years old around the Indian Ocean are associated with a 29 kilometre wide impact crater located thousands of kilometres to the southeast of Madagascar.
+"There are chevrons around the Indian Ocean that all point back to this one crater site," he says.
+And he says this is supported by evidence from an anthropologist on the team who found 170 myths and legends from the area dating back about 4000 years referring to an event that could have been the impact.
+Bryant says other evidence of a mega-tsunami as recently as 500 years ago has been found on the eastern coast of Australia.
+He and Abbott have linked this one to an impact crater south of Stewart Island in New Zealand.
+None of the research has been published but some of it will be presented at an American Geophysical Union meeting in San Francisco next month
+Mixed reception
+Earth scientist Professor Richard Arculus of the Australian National University says he accepts Bryant's evidence of mega-tsunamis.
+But he says working out what caused them and when will require more evidence.
+His colleague, marine sediment specialist Dr Bradley Opdyke, is also not yet convinced.
+"They're heading in the right direction," he says, but believes more evidence is required to prove the existence of the Indian Ocean crater.
+New Zealand-based tsunami expert Dr Mauri McSaveney of GNS Science says there is pretty good evidence that there are more large craters on our planet than mainstream scientists think there should be. 
+While he says Bryant's claims are "perfectly plausible" and the best available evidence suggests the New Zealand crater is one from the Holocene period, this could still be wrong.
+"He has yet to convince me, and a lot of others," says McSaveney.
+But as Arculus says, Bryant is fighting against a tradition in earth sciences that suggests everything we see around us is the product of slow processes rather than sudden catastrophic events.
+"Geologists are naturally anti-catastrophe," he says. "We're inclined to be conservative."
+
+Size matters, say researchers who are urging more scrutiny of nanotechnology
+Urgent research into the potential dangers of nanotechnology needs to be carried to convince the public of its future value in fields such as medicine and computing, scientists urge. 
+They believe the potential of nanotechnology, which operates on an atom-sized scale, will not be realised without clear information about the true risks and how to avoid them. 
+Dr Andrew Maynard, of the Woodrow Wilson International Center for Scholars in Washington, and 13 other international experts warn that time is running out to get it right.
+"If the public loses confidence in the commitment - of governments, business and the science community - to conduct sound and systematic research into possible risks, then the enormous potential of nanotechnology will be squandered. We cannot let that happen," they say in a commentary in the journal Nature.
+Nanotechnology is the design and use of particles as small as one-billionth of a metre. A human hair is about 80,000 nanometres across. 
+It is already being used in cosmetics, computer chips, sunscreens, self-cleaning windows and stain-resistant clothing. But materials on such a small scale can have different properties to larger versions. 
+The experts say instruments to assess environmental exposure to nanomaterials must be developed in the next three to 10 years and that methods are needed within the next 15 years to evaluate the toxicity of nanomaterials.
+They also stress the need to develop models within a decade to predict the potential impact of new nanomaterials on health and the environment, and strategic programmes for risk-focused research over the next 12 months. 
+"It is about whether governments, industry and scientists around the world are willing to make safe nanotechnology a priority," they add.
+
+Analysis of Neanderthal DNA shows they rarely interbred with our ancestors, as some scientists have suggested
+Researchers have sequenced DNA from the leg bone of a Neanderthal man who died 38,000 years ago and say it shows the Neanderthals are truly distant relatives of modern humans who interbred rarely, if at all, with our own immediate ancestors.
+They estimate that modern humans and Neanderthals split from a common ancestor at least 370,000 years ago, and possibly 500,000 years ago, although we share 99.95% of our DNA. 
+"We see no evidence of mixing 40,000, 30,000 years ago in Europe. We don't exclude it, but see no evidence," says Dr Edward Rubin of the US Department of Energy Joint Genome Institute in Walnut Creek, California, who led one study.
+This conflicts with some evidence from other researchers, including a team who said earlier this month that humans may have inherited a brain gene from Neanderthals. 
+The researchers reported their findings jointly in the journals Nature and Science.
+Rubin's team used one method to isolate and sequence part of the Neanderthal's DNA.
+Another team, led by Professor Svante Paabo of the Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, used a separate method to sequence a much larger amount.
+Paabo was the first scientist to find and sequence Neanderthal DNA, in 1997, and first suggested that Neanderthals did not mix with modern humans. 
+"I think the sequence data will serve as a DNA time machine that will tell us about biology and aspects that we will never be able to get from their bones and a limited number of associated artefacts," Rubin says. 
+Neanderthals and modern humans are both descended from Homo erectus, which left Africa and spread around the world about 1.5 million years ago.
+Living side by side
+Neanderthals lived in Europe and the Middle East until about 30,000 years ago. Cro-Magnon people, the ancestors of modern humans, started a second wave of migration out of Africa about 10,000 years earlier. 
+One huge question is how closely they interacted. Paabo's and Rubin's genetic analysis both suggest there was little sexual contact, at least according to the genes from this one male found at the back of a cave in Croatia. 
+Paabo's team sorted through 70 Neanderthal specimens before they found a bone well-preserved enough to provide DNA. They took the tiniest samples they could to preserve the valuable bones. 
+They know it was a male because the DNA has the telltale Y chromosome. 
+Paabo's team says it hopes to have a complete genetic sequence within two years.
+They say the Neanderthal sequences are 99.95% identical to human DNA sequences. This compares to about a 98% similarity between humans and chimpanzees, who split from a common ancestor 6 to 7 million years ago. 
+Three-way comparisons among the human, chimpanzee and Neanderthal genomes should shed light on what makes modern humans unique, experts agree. 
+Rubin and other experts stress that while full sequences of the human genome are available, very little is understood about what the code actually means.
+"We have the book but we haven't yet read it," Rubin says. 
+The researchers found, for instance, sequences linked with eye colour but cannot read the code to tell what colour Neanderthal eyes were.
+
+The robot can adapt to changes in both terrain and itself - walking on three legs, for example, if the fourth is lost
+A star-shaped robot that senses and responds to changes in the environment and damage to its own body has been developed by US researchers.
+Because the robot continually refines its built-in software to move efficiently - wherever it is, and whatever its condition - it could help shape the future of mobile robotics.
+The four-legged Starfish robot is reported by Dr Josh Bongard and team from Cornell University in today's issue of the journal Science.
+The robot can adapt to changes in both terrain and itself - walking on three legs, for example, if the fourth is lost. 
+The Starfish could lead the way for a new generation of autonomous robots that can quickly adjust to unpredictable environments and circumstances, much the same way people and other animals do. 
+The technology is "very powerful," says Professor Dario Floreano, director of the Institute of Systems Engineering in Lausanne, Switzerland.
+"It's a major advance in the field," says Floreano, who is not associated with the research. 
+The software in conventional robots typically doesn't account for unpredictable changes in the environment, or to the robot itself, that could restrict its movement. 
+But the Starfish can explore its own abilities and limitations, taking them into account before planning a move. 
+Robot sensing
+The robot begins by getting a sense of itself, testing each of its joints with random motions. Sensors on the joints capture each joint's range of motion and feed that information to the 15 mathematical models built into its controlling software. 
+Each model figures out one possible mode of locomotion. For example, one model might find how the robot is capable of scurrying scorpion-like on three legs, using the fourth like a tail for balance. Another might offer a way for the robot to scuttle sideways like a crab.
+Every model may be accurate on some level, but not all are efficient.
+To refine the results, a computer program searches through the models, looking for areas of disagreement among their results.
+"This is the key element of the entire process," says team member Dr Hod Lipson, director of the Computational Synthesis Laboratory at Cornell University.
+The most common disagreements represent the biggest flaws, he says. 
+To work out potential kinks in those areas, the robot performs each possible motion where the models disagree, feeding more data about the efficiency of each option back to models. 
+The cycle is repeated 16 times, and in the end, the last model standing is the one that instructs the robot where to go, and how. 
+Challenges ahead
+At the moment, all of the computations are run on a desktop computer. If the robot is to work autonomously, it will need that computing power onboard. 
+"That could be a potential challenge," says Floreano, especially if the robot is equipped with many sensors. 
+But he feels certain that the Cornell team has a solution and expressed confidence in the flexibility of the approach, which "can be applied to any type of robot."
+
+Many people have protested over the use of animals in experiments
+The use of lab animals to develop new medicines, cosmetics and pesticides could be eliminated by virtual experiments on computer, say European researchers.
+The virtual tests could be run using computer models that draw on a vast database of information about chemical compounds.
+And the system could also help develop new compounds in record time, the researchers say.
+Developing new chemical compounds consists of multiple steps, from identifying an active chemical among millions of potential leads to pinpointing a target.
+Finding an effective chemical requires a lot of mixing and matching of compounds in the lab. 
+But access to a centralised database of chemical candidates under development, known as Chemomentum, could help researchers save some lab time, and lab animals.
+Modelling tools available in the software could be used to optimise the chemical structure of the compound and analyse whether those changes make it interact better or worse with a potential target.
+Once the right chemical compound is pinpointed, it needs to be tested for effectiveness as well as toxicity. Classic toxicity tests are done by exposing animals to increasing doses of a chemical.
+At a low dose no effect is seen; at a high dose, all animals die. The right dose is somewhere in between. Based on such animal tests, the lethal dose of a chemical is extrapolated to humans.
+According to the British Union for the Abolition of Vivisection, 100 million animals are used in laboratories to tests range of goods, including household products, cosmetics, food additives, pharmaceuticals, and industrial and agricultural chemicals, to name a few.
+Mathilde Romberg, a research fellow at the University of Ulster in the UK and one of the principal investigators on the Chemomentum project, hopes the new system can reduce those numbers.
+Romberg has partnered with experts at eight universities, institutes and companies from France, Germany, Italy, Estonia and Switzerland to compile the system.
+She says the user-friendly program should "help the chemical industry and European regulatory bodies evaluate the substances and assess related risks, with fewer and fewer animal tests."
+In theory, experimental tests may not be necessary with Chemomentum. Rather, users would input information about the leads and targets they are interested in and the system would return the corresponding toxicity predictions.
+The software will be designed to perform calculations using standard PCs or draw upon the computing power of PC clusters - also known as grid computing - to crunch more complex data expeditiously.
+At the moment, the models that predict toxicity are new and people are sceptical about using them, said Paolo Mazzatorta, a scientist in the Chemical Food Safety Group at Nestl&eacute; Research Center in Lausanne, Switzerland.
+But experimental tests are expensive and that could eventually drive more interest in predictive modelling.
+"I think there will come a moment when this science will be more mature and it will be used," he says.
+
+Researchers are trying to find out more about paranormal experiences
+An international online survey of paranormal experiences has met with an overwhelming response, say Australian researchers.
+The survey, on phenomena that cannot be explained using the current laws of science, is by researchers at Monash University in Melbourne.
+"The paranormal is covered by the media everyday. It is also in the public domain via chatrooms and websites and email lists," says Rosemary Breen, who will use the survey results as part of a Masters degree. 
+"I wanted to tap into this and give a scholarly voice to these experiences."
+A recent Gallup poll revealed that 75% of Americans hold at least one paranormal belief, and a UK newspaper poll showed that 60% of Britons accept the existence of the paranormal, say the researchers.
+But little is known about contemporary spontaneous experiences, and official surveys are rare, they say.
+Breen says the survey is not about beliefs or whether parapsychological phenomena exist, rather it is about what people have experienced and the impact it has had on their lives.
+And she says she is not aware of any equivalent study in the world.
+Thousands of responses
+Some 2,000 people have made contact via the internet since the survey began six weeks ago, says Dr Beverley Jane, who is supervising Breen's research.
+She says 96% of respondents claim to have had at least one brush with the paranormal,
+The exercise seeks to gauge the frequency, effect and age of onset of unexplained phenomena such as premonitions, out-of-body and near-death episodes, telepathy and apparitions. 
+Results to date showed 70% of respondents believe an unexplained event changed their lives, mostly in a positive way. 
+Some 70% also claim to have seen, heard or been touched by animal or person that wasn't there, 80% report having had a premonition, and almost 50% recalled a previous life. 
+"The respondents are sincere and they want to report what they have experienced," Jane says. 
+She is amazed by the strong response on such a sensitive subject, and put this down to the virtual nature of the study.
+"People can do it in the privacy of their homes instead of in front of the researcher, so they can answer honestly," she says.
+While the survey was anonymous, some people later sent emails with their contact details, Jane says. 
+She says the study is not seeking to assess respondents' mental health, but says it does offer people the chance to tell somebody about experiences they would normally keep to themselves.
+Due to the overwhelming response to the survey the researchers expect to extend the closing date for responses past its initial November deadline.
+
+Massage may make baby happier, but the evidence to date suggests it won't improve physical or emotional development
+A gentle massage appears to lower levels of stress hormones in unsettled babies, but there's no evidence that infant massage has any benefit on growth or development, a scientific analysis shows.
+Infant massage has long been used in many Asian and African cultures to ease colic and crying, help babies sleep, and even aid their growth and development. 
+There has also been growing interest in infant massage among parents in Western countries. 
+UK researchers seeking to assess the science behind the practice analysed 23 clinical trials.
+They report their findings in the latest issue of The Cochrane Library, a publication of the Cochrane Collaboration, an international organisation that evaluates medical research.
+The trials involved infants aged six months and under who were randomly assigned to receive massage or not.
+The researchers found that across nine of the studies, gentle massage appeared to improve infants' sleep patterns, ease crying, and strengthen mother-child bonding. 
+Some studies found that massage reduced babies' levels of the stress hormones norepinephrine and epinephrine and appeared to release melatonin, which is associated with sleep patterns.
+Given this apparent hormonal effect, it's "not surprising" that massage seemed to improve sleep and crying, according to the researchers, led by Dr Angela Underdown of the University of Warwick in Coventry, England. 
+Tentative support
+But the nine studies failed to come up with any evidence of cognitive or behavioural benefits.
+"There is no evidence of any impact on infant attachment, temperament, psychomotor or mental development," the researchers say.
+Overall, the results offer "tentative support" for teaching parents and caregivers infant massage, the investigators conclude.
+But they say there isn't enough evidence to universally recommend the practice.
+The trials included in the review were conducted in China, North America, Great Britain and Israel, and included 598 healthy, full-term infants. 
+In some studies, researchers provided the massage, while parents did in others.
+Most looked at the effects of daily massage over a period of weeks. 
+The researchers said 14 of the 23 trials they looked at were not entirely reliable because of concerns about their methodology.
+For example, some lacked information about how the study was designed and conducted, meaning more quality research is needed. 
+It's also unclear how often, when or for how long babies should receive massage to get the most benefits. 
+Underdown and colleagues recommend that future studies examine these questions.
+
+New research suggests that whale communication is even more sophisticated than previously thought
+Whales have such a broad vocal repertoire that they can call to their young, woo potential mates and even express emotions, according to researchers who have identified 622 social sounds in humpback whales.
+Their work will be presented at the upcoming joint meetings of the Acoustical Society of America and the Acoustical Society of Japan in Hawaii.
+Social sounds are brief, unpatterned noises that are distinct from lengthier, complex whale songs.
+The new research adds to a growing body of evidence that whales convey more meaning through vocalisations than previously thought.
+"I wouldn't say (whales possess) language, as that's a human term," says Dr Rebecca Dunlop, a researcher in the School of Veterinary Sciences at the University of Queensland, who worked on the study.
+"Whales don't string these sounds together like words and form sentences. It's more like a simple vocabulary," she says.
+The scientists visually tracked 60 pods of whales migrating along the east coast of Australia.
+The researchers used a static hydrophone array, sensitive equipment that detects sound waves, linking the whale sounds to various activities and contexts.
+Wops, thwops and yaps
+They identified 622 distinct sounds, which fell into 35 basic types.
+These include "wops" made by females, "thwops" made by males, "yaps" made when pods split, and high pitched cries that appeared to express anger.
+In addition to vocalisations, the researchers found that whales send messages through body language, by breaching the surface, slapping water with their tails and blowing underwater bubbles.
+Famous for their long, complex songs, whales also sometimes "speak" short song units individually instead of singing them.
+Males especially seem to do this when trying to woo a female.
+"Song is a loud broadcast signal and two singers singing at the same time is bound to be confusing to the receiver," Dunlop says.
+"If he's trying to attract a female, but doesn't want his signal confused with another singer in the area, then using song units in this case might be the way forward."
+She thinks one reason whales are so vocal is because sound travels better in water than light, and so sight is less useful to whales than hearing.
+Human interference
+Dr Christopher Clark, director of the Bioacoustics Research Program at Cornell University, conducted a similar study on right whales.
+He says that just as researchers are gaining a better understanding of whale vocalisations, humans are creating so much ocean noise, through shipping, oil and gas exploration, recreational traffic and more, that we often prevent whales from communicating.
+"Many whales have very traditional feeding grounds and their migratory routes occur along shallow coastlines, which are now some of the noisiest, most heavily impacted habitats," he says.
+"The ocean area over which a whale can communicate and listen today has shriveled down to a small fraction of what it was less than a century ago."
+
+Scientists say they can genetically engineer cotton plants to remove a toxic compound, making cottonseed fit for humans to eat
+Scientists say they have found a way of using the cotton plant to feed potentially half a billion people a year.
+Texas A&M University plant biotechnologist Associate Professor Keerti Rathore and colleagues report they have genetically altered the plant to reduce the levels of the toxic chemical gossypol in cottonseed, making it fit for humans to eat.
+"It actually tastes pretty good. It reminds me of chickpea. It's a fairly good-tasting seed," he says. 
+"It tasted better than soybean, I can tell you that," adds Rathore, who publishes the team's research in the Proceedings of the National Academy of Sciences.
+The protein-rich, GM cottonseed could be ground into a flour and made into bread and other foods, he says. 
+Rathore and his team turned to a technique also being used in cancer and AIDS research.
+They used so-called RNAi or RNA interference technology that can 'silence' a gene to cut the amount of gossypol in the cottonseed.
+When humans eat gossypol it can damage their heart and liver. 
+The researchers left gossypol intact in the rest of the plant because it guards against insects and disease. 
+"So the trick is not to affect the levels of these compounds in the rest of the plant, but eliminate it from the seed only. And that's what we have done," Rathore says. 
+This cottonseed could serve as a high-protein food for the world's hungry, and falls well within the criteria set by the World Health Organization and US Food and Drug Administration for food consumption, the researchers say.
+"Potentially, if all of the cottonseed today which is produced can be utilised for human nutrition directly, it can meet the protein requirements of 500 million people on an annual basis," Rathore says. 
+Wasted protein
+"That is a lot of protein right now really being wasted," he adds, noting that cottonseed often is fed to cattle because bacteria in their stomachs can break down gossypol.
+The chemical is present naturally within the glands in the above-ground parts of the cotton plant. 
+For millennia, people have spun cotton fibres into clothing and other fabrics. But for each kilogram of cotton fibre, the plant produces 1.6 kilograms of seed, Rathore says.
+Cotton is grown in more than 80 countries worldwide. With the exception of the US and Australia, he says, it is grown primarily in developing countries.
+Researchers estimate that it will take at least another decade to develop cotton varieties with these qualities for broad commercial production. 
+In the 1950s and 1960s, agricultural scientists bred cotton varieties that had no gossypol glands. But they were a commercial flop because the absence of the toxin made the plants too vulnerable to insects and disease. 
+In addition to edible cottonseed, the RNAi technique might be applied to other crops with toxic components, such as fava beans, to increase their use, the researchers say.
+
+Firefighters face long-term health risks, new research shows
+Firefighters appear to have higher-than-average rates of cancer, the largest study of its kind shows. 
+The analysis, of 32 previous studies, shows that firefighters are at greater risk of prostate and testicular cancers, as well as the immune system cancers non-Hodgkin's lymphoma and multiple myeloma.
+Eight additional cancers show possible links to the job, according to findings published in the Journal of Occupational and Environmental Medicine. 
+Firefighters are exposed to many potentially cancer-causing chemicals released from burning materials.
+Though they wear breathing apparatus and other protective equipment while fighting fires, researchers point out, they typically remove the gear when they're merely in the vicinity of the fire. 
+At the scene of the fire, toxic substances such as benzene, lead, uranium and asbestos can be inhaled or absorbed through the skin. And at the fire station, idling trucks expose firefighters to diesel exhaust. 
+The cancer risks seen in this latest study suggest that firefighters need better on-the-job protection, according to the study authors. 
+"Firefighters work in an inherently dangerous occupation on a daily basis," says lead author Dr Grace LeMasters of the University of Cincinnati College of Medicine.
+She and her colleagues based their findings on an analysis of 32 international studies that included more than 110,000 firefighters in all. 
+Across the studies, firefighters had double the risk of testicular cancer as men in other occupations, a 50% higher risk of both multiple myeloma and non-Hodgkin's lymphoma, and a 28% higher risk of prostate cancer. 
+These findings "raise red flags", LeMasters and her colleagues write, and point to a need for "innovative comfortable protective equipment allowing firefighters to do their job without compromising their health". 
+Another, more immediate measure would be for firefighters to shower as soon as they return to the fire station, the researchers say.
+Other investigators, they note, have found that firefighters often say their skin ends up covered in soot after battling a blaze.
+
+Male chimps fight over older females, who are seen as a prize catch
+Chimpanzee males prefer to have sex with older females, according to US researchers, showing one of the biggest behavioural differences between humans and our closest biological relatives.
+Male chimps will chase down and fight over the oldest females.
+Meanwhile, the youngest female chimps are forced to beg for masculine attention, say anthropologist Assistant Professor Martin Muller and colleagues at Boston University. 
+"It's really dramatic because it's not just that the old chimps are avoiding the youngest adult females. They actually have a strong preference for the older mothers," Muller says. 
+Writing in the journal Current Biology, Muller and colleagues say they studied chimpanzees living in the Kanyawara community of Kibale National Park in Uganda. 
+It is easy to observe their mating behaviour. 
+"Chimpanzee copulations are frequently preceded by a series of male courtship signals (eg, glancing with erect penis and branch shaking), after which either the male or the female approaches the other to mate," the researchers write. 
+They also collected the chimps' urine to test for various hormones that demonstrate fertility. 
+The researchers were checking to see if chimpanzees behave like humans, their closest living relatives, who form long-term mating bonds and who value younger females. 
+This is most definitely not the case with chimps. The very oldest adult females were the most sought after. 
+"The males fight over them more," Muller says. 
+"They don't have to do anything to get the males interested. The males find them. They follow them around. If you look at the very youngest females, the males will mate with them but it does take more work on the female's part." 
+Showing off
+Also unlike humans, female chimpanzees actively advertise when they are fertile, with bright red swellings around the genital area.
+And unlike human females, chimpanzees apparently remain fertile their entire lives, although these wild Ugandan chimpanzees rarely lived beyond the age of 40.
+Muller says that older female chimpanzees are more dominant socially and have access to better food. 
+"The females that have access to the most food are the most fecund, the most likely to conceive in any cycle," he says. And males may know that.
+Older females may also be better mothers, the researchers guess. 
+"The males do end up mating with all the females for the most part," Muller notes. But he says the study challenges common conceptions. 
+"Normally, I think peoples' default assumption is, 'Well other animals, they must also find young females attractive'," Muller says. "And people assume that young females are more fertile than older females." 
+But female chimpanzees do not experience the rapid decline in fertility that is seen in human females after their 20s.
+
+What happens to tissue that's removed during a biopsy and stored in liquid nitrogen?
+Some Australians are concerned that tissue samples held by hospitals could be used to make human clones, a survey of public attitudes towards tissue banking reveals.
+Early findings from the study, by researchers from the Centre for Values, Ethics and the Law in Medicine at the University of Sydney, show some people are also opposed to biopsy tissue, such as cut-out tumours, being used as a source of stem cells or by drug companies.
+Most hospitals have a collection of tissue that's been removed for diagnosis and serves as a research resource.
+The tissue can be used for in-house research or passed on to other institutions and private companies.
+But the laws relating to stored tissue are confusing and contradictory because of differences between state and federal jurisdictions, says Bronwen Morrell, who will present the study's interim findings at the Australian Health and Medical Research Congress in Melbourne this week.
+She says her study indicates that people want laws setting down basic parameters about consent, information about the type of research and whether their tissue can be used for profit.
+Morrell asked participants a range of questions including whether there was any sort of research they wouldn't want their tissue used for.
+"Two things that came up repeatedly were cloning and stem cells," she says.
+"Cloning came up repeatedly, which is interesting because I think they were thinking of reproductive cloning which isn't allowed in Australia anyway ... but obviously that's something that's very much on their mind."
+The federal government is currently debating recommendations of the Lockhart Review to allow therapeutic cloning in Australia, but reproductive cloning remains banned.
+Morrell says the study also shows some people trust the public sector more with their tissue than private companies.
+"As long as research was being done in a public hospital they would feel comfortable with that," she says.
+"But if it was a private company doing the research, especially drug companies, they wouldn't be that happy."
+Some people also wanted any profit made out of their tissue to go back into research, she says.
+Dr Wendy Lipworth, who was involved in the research, says that genetic technology has raised new issues for tissue banks.
+"I think 30 or 40 years ago nobody would have thought anything of it, they would have thought why would I care, it's just the leftover bits of my tumour," she says.
+"But as genetic technology has evolved you can find out more and do more with that material. There wasn't as much at stake until recently."
+Recommendations
+The current survey is part of a three-part study into in the ethics of tumour banking.
+The first part of the study, published in the Journal of Law and Medicine this year, surveyed hospitals and private research institutions.
+The second part, which questioned experts and medical professionals, is still being analysed.
+The third and final part subjected 20 people including patients, parents, consumer representatives and health advocates to a in-depth one hour interview.
+Morrell says researchers hope to publish a series of reports when the results are fully analysed.
+The researchers may also make recommendations about the sorts of procedures that tissue banks should follow, Worrell says.
+
+Scientists say they haven't heard from the Mars Global Surveyor in weeks
+NASA scientists conceded that the 10-year-old Mars Global Surveyor is probably lost in space after the US agency tried unsuccessfully for two weeks to make contact.
+The spacecraft, the oldest of five NASA robotic explorers studying Mars, was circling the planet snapping high-resolution images and studying the climate.
+It was on a mission that led to the first evidence that water once flowed on the planet's surface. 
+The probe went silent after reporting problems with a sticky solar panel, and scans of the skies have produced no sign of it. 
+"[Mars Global Surveyor] was a fantastic mission. It has really revolutionised how we look at Mars," says Dr Fuk Li, Mars Exploration Program manager.
+"We haven't given up hope, but we are all ready to celebrate a long life and a job well done." 
+One chance remained this week to recover the probe, which has been programmed to transmit a signal to NASA's robotic geology station, Opportunity, located near Mars' equator. 
+Opportunity will relay any signal from the orbiter to Earth during passes this week via the Mars Odyssey. 
+"If [Mars Global Surveyor] is in the sky and its [transmitter] is on, then Opportunity should receive it," says Dr John Callas, project manager for the Mars Exploration Rover mission.
+Scientists at NASA's Jet Propulsion Laboratory in Pasadena, California, lost contact with the spacecraft on 2 November after it signalled it was having trouble moving one of its solar panels to track the Sun as it emerged from behind Mars.
+The spacecraft is programmed to position itself so that a stuck panel faces the Sun, but that orientation could block its communication with mission controllers, says Tom Thorpe, the Mars Global Surveyor project manager.
+Power problem
+If Mars Global Surveyor is turned away from the Sun for more than a few orbits it could be low on power, an outcome that seemed to be supported by the spacecraft's apparent failure to respond to commands that would raise its transmitter, Thorpe says.
+"We don't believe the [solar] panel is in any way degraded ... the problem seems to be the gimble motor that is sticking," Thorpe says. "Why we can't raise the transmitter could be a function of the power problem." 
+Mission scientists first hailed the orbiter via the Deep Space Network, receiving what they believed was a weak carrier signal from the probe two or three days into the search. Then it went silent. 
+They then turned to the newly arrived Mars Reconnaissance Orbiter, which used its onboard cameras during recent passes near Mars Global Surveyor's last known orbit. But that probe had no definitive sightings of its sister craft. 
+If Opportunity records no sign of Mars Global Surveyor, scientists say they will have exhausted the most likely possibilities for contacting it.
+The 10-year mission, which was extended four times, cost a relatively modest US$377 million (A$489 million). 
+Mars Global Surveyor's cameras were the first to record topographic features suggesting flowing water on Mars, and its magnometer found the remains of magnetic fields that once shielded Mars' surface from deadly cosmic rays. 
+Its mineral mapping helped scientists choose landing sites for Opportunity and its twin, Spirit, and will be used to evaluate landing sites for the next-generation of Mars surface probes, the Phoenix and the Mars Science Laboratory.
+
+Tall men have the advantage when it comes to speed-dating
+If you want to be a big hit at speed-dating, walk tall, say UK scientists.
+Their survey found that taller men are more likely to get a date.
+The University of Essex scientists calculated that for every 2.5 centimetres taller a man is than his speed-dating rivals, the number of women who want to meet him goes up by about 5%.
+Dr Michele Belot and Dr Marco Francesconi analysed the choices made by 1800 men and 1800 women at 84 speed-dating events. 
+They found that women prefer men who are young and tall, while men are more attracted to women who are young and thin.
+"What we try to show is that there is a pattern in how people choose each other," says Belot. 
+But she readily concedes that science does not have the answer to all affairs of the heart.
+"It is true we can explain quite a lot, but there is still a part that is unexplained. That is where love will play a role," she says. 
+But, in the unforgiving numbers game of love, age is crucial. 
+Each extra year, in comparison with others in the speed-dating group, reduces a man's chance of finding a partner by 4%. For women it is 5%. 
+And it is often all about the luck of the draw on the big night.
+Should a man of average height turn up at the speed-dating event, all is not lost. 
+If all his male rivals are short, then women may decide that he does measure up after all. 
+"We also found that an overweight woman is 16% less likely to receive a proposal from men. Men, on the other hand do not seem to be penalised for being overweight," Belot says. 
+The survey also explodes the myth that blondes have more fun. Hair colour was not a major issue when speed-dating.
+And when the big night was over, women were much pickier than men, choosing only 2.6 men as possible future dates.
+To add insult to injury, almost half of the women said they did not want to see any of the men again.
+
+Green turtle returning to the sea after laying a clutch of eggs on the beach at Enu Island in Indonesia
+Scientists have conducted the first genetic census of endangered green turtles throughout southeast Asia and Australia, providing a conservation tool.
+"The green turtle is on the red list of endangered species internationally, so we wanted to be able to identify if there were particular groups that might need specific conservation efforts," says PhD student Kiki Dethmers from the University of Queensland.
+Her work on the turtle Chelonia mydas appears in the November issue of the journal Molecular Ecology.
+Turtle populations are shrinking for a range of reasons, she says.
+Some are hunted for food, others are accidentally caught in fishing nets, while others still are affected by a loss of habitat or viral diseases.
+Dethmers and her colleagues gathered skin or blood samples from turtles nesting at 27 different sites in Malaysia, the Philippines, Micronesia, Indonesia, Papua New Guinea and Australia.
+From each sample they extracted a mitochondrial DNA, genetic material that is passed down from mother to child.
+"Mitochondrial DNA is inherited through the female line, and females come to the beaches to nest, so our study was based on sampling the female population," Dethmers says.
+The results show that there are just 17 distinct genetic groups within the region.
+Some groups were made up of a single nesting beach. But in other cases, nesting sites in different locations turn out to be genetically related.
+Some of the groups were substantial, such as the 125,000 related turtles that nest on Western Australia's northwest shelf.
+Others, like some groups in Malaysia, might contain just a few hundred turtles.
+The information Dethmers and her colleagues have gathered could be vital for future conservation efforts.
+"The turtles' situation varies from one area to another," she says. "Our data would be useful for example if one of the groups is particularly threatened, because it would give you an idea of how many turtles are being affected.
+"This can help you make predictions about whether that is going to make a certain population go extinct."
+
+Cooling towers are one option for getting rid of waste heat from power plants
+Any Australian nuclear power plants would most likely need to be built on the coast where gigalitres of seawater could be used to cool them, suggest experts.
+"Because we've got a water shortage in this country it would be best to place them on the coast," says nuclear power engineer Professor John Price of Monash University in Melbourne.
+Price's comments come in the wake of a draft report from Prime Minister John Howard's nuclear taskforce that proposes constructing 25 nuclear power plants to meet Australia's future energy needs.
+Price, who welcomes the new report, says "gigantic" amounts of water are required to cool a nuclear power station.
+"I'm talking about tonnes per second," says Price, who has designed nuclear power stations in the UK.
+According to the taskforce, headed by nuclear physicist Dr Ziggy Switkowski, nuclear power plants are less efficient than coal-fired plants and thus require more cooling.
+One estimate, from a recent report to the Queensland government, suggests a 1400 megawatt nuclear power station would use around 25 gigalitres of water a year.
+This is about 1.26 times the water used by an equivalent coal-fired power station, says the report by Dr Ian Rose of Roam Consulting, a Queensland-based company with expertise in energy modelling.
+Water cooling
+While the Switkowski report does not consider specific locations for nuclear power plants in Australia, it says they are often located near existing power stations because this ensures ready access to appropriate infrastructure and water for cooling.
+Most nuclear power stations are cooled using water from a river, lake or the ocean, the report says.
+But the Rose report says a lack of reliable river water makes a nuclear power station cooled by river water "not an option for Australian conditions".
+Both Rose and Price also raise the issue of environmental effects of the warmer water discharged from nuclear power stations on rivers.
+"I wouldn't think that would be a good idea [siting a nuclear power station on a river] in Australia because the river volumes are not huge and you don't want to heat the river up," says Price.
+Price suggests power stations by the sea are preferable because the sea can more easily dilute the heat of the discharge.
+But Rose says it may be difficult to find suitable seaside locations.
+"The number of seaboard nuclear sites in areas close to a major transmission grid in eastern Australia is likely to be limited," his report says.
+The US Environmental Protection Agency says that discharge from nuclear power stations can also contain heavy metals and salts that can harm aquatic life.
+It also says removal of water upstream in the first place can also damage river environments.
+Cooling options
+Instead of discharging warm water, some nuclear power stations evaporate water into the air through cooling towers, Price says. 
+While Rose says this is a preferred option, Price says this is a waste of water.
+According to the Switkowski and Rose reports, it is also possible to use 'dry' cooling, which reduces water consumption by using air as a coolant. But they say this would be more expensive.
+Another option, says Price, is to use waste heat from nuclear power stations to desalinate water.
+"That may be one of the most interesting outputs, as far as Australia is concerned," he says.
+The nuclear taskforce is inviting public submissions on its draft report until 12 December and the final report is due at the end of the year.
+
+Left-handed people seem to have better connections between the left and right halves of their brain. So does this mean they are better at complex tasks like gaming?
+Left-handed people often perform better than right-handers at fast or difficult tasks that involve lots of information or stimuli, new research suggests.
+For instance left-handers might be better at playing fast computer games, talking while driving in heavy traffic and piloting a jet fighter - activities that need both hemispheres of the brain to process information.
+Research shows that the left and right hemispheres communicate and work together better in left-handers, as information transfers from one to the other slightly faster and perhaps more efficiently.
+Dr Nick Cherbuin from the Australian National University and colleagues report their findings in the November issue of the journal Neuropsychology.
+He says the left-hander's brain is wired slightly differently to the right-hander's as it tends to be more symmetrical with larger and perhaps faster connections between hemispheres.
+The research found that on average those with faster connections were more efficient at performing tasks that require processing in two hemispheres.
+"Typically we tend to use more our two hemispheres together  when tasks are very fast or very hard and one hemisphere does not have enough resources to cope," Cherbuin says. 
+"Examples might be dealing with multiple stimuli that are presented very briefly or tasks which require interpretation of a lot of information such as talking while driving in heavy traffic, piloting a jet fighter or playing fast computer games.
+"As our brain ages we lose processing resources in the two hemispheres but left-handers may be able to cope better because the sharing of resource across their hemispheres is more efficient."
+The computer tests in 80 right and 20 left-handers measured how fast information transferred between hemispheres by hitting a button to indicate whether a light flash was left or right of a dot.
+Another test to match letters found left-handers performed better when letters flashed on both sides of the dot, requiring collaboration across hemispheres.
+Right-handers did better when letters were on the same side of the dot, making them more efficient at single hemisphere processing. 
+Cherbuin, a right-hander, says the 7-10% of people who are left-handed adjust to our right-handed world by using their right hand more.
+
+Superimposing copy number profiles of different human genomes shows each chromosome has distinctive pattern of DNA gains (shown in green) and losses (red). Yellow areas show where there is no difference
+New investigations into the code for life suggest the assumption that humans are genetically almost identical is wide of the mark, and the implications could be resounding. 
+Current thinking, inspired by the results five years ago from the Human Genome Project, is that the 6 billion humans alive today are 99.9% similiar when it comes to genetic content and identity.
+But research published today in the journal Nature suggests we are genetically more diverse.
+The repercussions could be far-reaching for medical diagnosis, new drugs and the tale of human evolution itself, the researchers say. 
+Until now, analysis of the genome has focused overwhelmingly on comparing differences, or polymorphisms, in the patterns of single letters in the chemical code for making and sustaining human life.
+But an international consortium of scientists has taken a different tack and believes it has uncovered a complex, higher-order variation in the code. 
+This better explains why some individuals are vulnerable to certain diseases and respond well to specific drugs, while others swiftly fall sick or never respond to treatment, the authors believe.
+Their focus has been to dig out deletions or duplications of code among relatively long sequences of individual DNA and then compare these so-called copy number variations (CNVs) across a range of volunteers of different ancestry. 
+The researchers were astonished to locate 1447 CNVs in nearly 2900 genes, or around one eighth of the human genetic code.
+"Each one of us has a unique pattern of gains and losses of complete sections of DNA," says Dr Matthew Hurles of the UK's Wellcome Trust Sanger Institute, one of the project's partners.
+"One of the real surprises of these results was just how much of our DNA varies in copy number. We estimate this to be at least 12% of the genome.
+"The copy number variation that researchers had seen before was simply the tip of the iceberg, while the bulk lay submerged, undetected. We now appreciate the immense contribution of this phenomenon to genetic differences between individuals." 
+Some of the missing or duplicated stretches are very long, suggesting that, like backroom switches in a protein factory, CNVs must have a big impact on gene expression.
+Genetic diseases
+Nearly 16% of genes that are known to be related to disease have CNVs, the group found.
+These include genes involved in rare genetic disorders such as DiGeorge, Williams-Beuren and Prader-Willi syndromes and those linked with schizophrenia, cataracts, spinal muscular atrophy and atherosclerosis. 
+But kidney disease, Parkinson's, Alzheimer's and vulnerability to malaria and HIV, which recent research has blamed on  single-letter variations in the gene code, may also well be rooted in CNVs, the scientists believe. 
+"The stage is set for global studies to explore anew ... the clinical significance of human variation," say Professor Huntington Willard and Dr Kevin Shianna of the Institute for Genome Sciences and Policy at Duke University in North Carolina, in a review of the research.
+How about evolution?
+Evolution is another area that will come under new scrutiny. 
+The Out of Africa scenario, by which Homo sapiens emerged from east Africa and spread around the globe, will not be challenged, though. 
+Our origins are so recent that the vast majority of CNVs, around 89%, was found to be shared among the 269 people who volunteered blood as samples for the study.
+These individuals included Japanese people from Tokyo, Han Chinese from Beijing, Yoruba from Nigeria and Americans of northern and western European ancestry.
+All the same, there are widespread differences in CNVs according to the three geographical origins of the samples. 
+This implies that, over the past 200,000 years or so, subtle variants have arisen in the genome to allow different populations of humans adapt to their different environments, according to scientists at Wellcome Trust Sanger.
+The research is based on two technical advances, one in faster, accurate sequencing of DNA and the other in a powerful software programme to spot the CNVs.
+
+The first supernova, ringed on the right in the image, was detected in June and the second supernova, on the left, in November. The central bright spot is the galaxy core and the bright object to the far left, like an earring, is a foreground star
+Stars are blowing themselves to smithereens more often than usual in galaxy NGC 1316.
+Astronomers have stumbled across two supernovae letting loose there just months apart, in addition to two previous mega-blasts in the past 26 years. 
+That makes the rate of exploding stars in NGC 1316 many times higher than any other known galaxy.
+The NASA Swift satellite observatory detected the recent twin supernovae on 19 June and 5 November of this year.
+In the images, the supernovae are visible on either side of the bright galaxy centre. 
+"It is actually very puzzling," says Professor Neil Gehrels, a Swift investigator at NASA's Goddard Space Flight Center.
+"That's the most [supernovae] there have ever been in such a short time."
+A more typical rate is around one a century in a given galaxy.
+So what makes NGC 1316 different? Not a lot, at least so far as researchers can tell.
+It's a large elliptical galaxy about 80 million light-years away, believed to have recently collided and merged with a spiral galaxy, which may have something to do with the accelerated rate of supernovae, or not.
+Galactic mergers are believed to stir up cosmic dust in a way that can create supermassive stars, the sort that eventually explode as supernovae.
+But the supernovae in NGC 1316 have the spectral fingerprints of type 1A supernovae, which begin as small, dying white dwarf stars rather than supermassive ones.
+There's no reason to believe that a galactic merger would create a larger number of white dwarfs than normal. So the mystery continues.
+Baby boomers
+Another possible explanation is that there are an inordinate number of white dwarfs in NGC 1316, which are the corpses of an extraordinary 'baby boom' of stars in NGC 1316.
+If that's the case, a surge of white dwarf-triggered supernovae would be expected when all the 'boomer generation' stars reach a similar age. 
+On the other hand, it could just be chance.
+Of the thousands of observable galaxies, odds are in favour of an occasional random clustering of supernovae in one galaxy, says John Nousek, a professor of astronomy and astrophysics at Pennsylvania State University.
+"This sort of thing is more of a cosmic coincidence than a cosmic Rosetta stone," says Nousek.
+He and graduate student Peter Brown have been hard at work monitoring and trying to make sense of the double explosions. 
+"The exact mechanism is not well understood," says Gehrels. "This is a fairly hot topic."
+
+Silicon has been converted into a superconductor, but at very low temperatures. If this could be reproduced at room temperatures, then we could build super-efficient computer circuit boards
+Scientists say they have treated silicon, the material of choice for semiconductors, so that it paradoxically becomes a superconductor, a material that offers no resistance.
+This potentially has huge uses in the efficient transfer of energy, whether that's on a large scale like electronic cables or on a smaller scale, like in a computer chip.
+But superconductivity in the treated silicon occurs only at 0.3&deg;K, or 0.3&deg;C above absolute zero.
+This means the novel material has no practical use and is only of theoretical interest right now.
+Dr Etienne Bustarret of France's National Centre for Scientific Research (CNRS) in Grenoble and colleagues converted the silicon by 'doping' it with high levels of boron, using a pulsed laser at normal pressure.
+They publish their research today in the journal Nature alongside a commentary that describes the findings as "a breakthrough".
+Superconductivity has been found in only a number of materials which, at very cold temperatures, allow electricity to flow through them without offering any resistance or losing some of the energy as heat.
+Scientific but also industrial interest in superconductors is huge, as superconductive cable and dynamos would be many times more energy-efficient than traditional copper and other conductors. 
+In addition, superconductor computers could be many times faster than today's.
+Their semiconductors would not be hampered by heat, one of the biggest problems facing designers today who are tasked with crowding ever more circuits onto a chip.
+Exotic oxides, cooled by liquid nitrogen, have provided the best transition temperatures to superconductivity, with temperatures as high as 160&deg;K.
+
+Stripes on the shoulder of this basketball jersey light up for each foul the player commits
+An Australian researcher has developed a sports jersey that lights up to show players' goals or fouls, and how much time they have left to play.
+The jersey is called TeamAwear and is the brainchild of design computing student Mitchell Page of the University of Sydney.
+In fast-scoring games like basketball it can be quite hard to keep up-to-date with constantly changing statistics that help you understand what's going on, says Page.
+While some information is posted on the scoreboard this can be difficult to look at during the game.
+Page decided that displaying information on players' jerseys would be a good idea because these are at the centre of the game.
+"Everyone's focus is directed towards them," he says.
+And the jerseys could display real-time information on individual players that is generally not publicly available.
+Page developed a basketball jersey with displays made out of electroluminescent panels that light up when electricity flow through them. These are connected by conductive thread woven into the jersey.
+A microcontroller communicates via a wireless connection to a computer at the bench, where someone can input the detailed information as required.
+There are four stripes over the jersey's shoulder that light up as the number of fouls increase and three bars on the side of the jersey each representing 10 goals.
+Two bars on the front of the jersey warn the player when they are nearly out of time. 
+One warns when the game is nearly up and the other warns when they need to shoot without incurring a penalty.
+And panels on the back, mainly for the benefit of the spectators, light up to show the winning side.
+Page says when players tested the jerseys they found they were comfortable to wear and improved play by giving them immediate access to more information.
+He says the players found the displays intuitive and easy to understand without being distracting.
+The warning lights on the front were the most important. If it was a tight game they could pick up pace. But if a player had a lot of fouls, they would have to play conservatively.
+Players might also choose the displays to choose a high-scoring player to pass the ball to.
+Page says the jerseys also had an unexpected effect on players' psychology.
+"Athletes said they were more confident when they could see that they had high points or they could see that they were winning," he says.
+The coach and referee can also use the displays to choose who to keep on the court, without having to refer to the benches and scoreboards as often, says Page.
+Page says while slow sports like golf would probably not benefit from his jersey, he hopes the idea can be applied to other team activities.
+He says it might be useful for emergency service personnel working in noisy, chaotic environments where verbal communication is difficult.
+Teams of people with hearing disabilities, debaters and possibly even orchestra members, might also benefit from the technology, says Page.
+
+Wild emmer wheat, shown here, is more nutritious than some types of domestic wheat. So scientists have crossbred new and old strains to improve levels of protein, zinc and iron
+Scientists have found a way to boost wheat's nutrient content by reintroducing a gene that was 'lost' over the years as the wild plant was domesticated.
+Writing in the journal Science, the researchers say they used conventional breeding methods to bring the gene into cultivated wheat varieties, enhancing their protein, zinc and iron value.
+The gene, which Professor Jorge Dubcovsky from the University of California, Davis and colleagues have identified, has became nonfunctional for unknown reasons over the years.
+This occurred as humans cultivated the wild wheat, known as wild emmer wheat (Triticum turgidum ssp dicoccoides).
+Wheat represents one of the major crops feeding people worldwide, providing about 20% of all calories consumed.
+The World Health Organization says that upward of 2 billion people get too little zinc and iron in their diet, and more than 160 million children under the age of 5 lack adequate protein. 
+"We really can produce wheat with more protein and more zinc and iron," Dubcovsky says.
+"So if that is grown in a developing country or is used as food aid, it will really provide more of those needed things in places where it's necessary." 
+Same taste
+In making the wheat more nutritious, the researchers did not change how it tastes, Dubcovsky says.
+"We're not changing the composition or anything very dramatic in the grain," he says. 
+"I don't think a simple step like this will solve hunger in the world. I'm not that naive. But I think it's heading in the right direction," Dubcovsky says. 
+The gene made the grain mature more quickly while also boosting its protein and micronutrient content by 10-15% in the pasta and bread wheat varieties with which the researchers worked.
+"What this gene does is it uses better what is in the plant already, so rather than leave the protein and the zinc and iron in the straw, we've moved a little bit more into the grain," Dubcovsky says. 
+The wheat varieties bred by the scientists are not genetically modified, which could help them become accepted commercially, they say. 
+"We didn't do it by genetic modification. The normal wheat crosses perfectly well with the wild wheat. So we just crossed it after normal breeding," Dubcovsky says.
+The research team includes scientists from the US Department of Agriculture and the University of Haifa in Israel. 
+Dubcovsky heads a consortium of 20 public wheat-breeding programs called the Wheat Coordinated Agricultural Project.
+Annual wheat production is estimated at 620 million tonnes of grain worldwide.
+
+The mass extinction known as the Great Dying 250 million years ago had profound and lasting effects on marine life. The upper part of the image represents life before the mass extinction, the lower part afterwards
+About 95% of the Earth's marine species and 70% of its land species were wiped out during a mass extinction about 250 million years ago, according to Australian and US researchers.
+This event, which occurred at the end of the Permian age and is known as the Great Dying, fundamentally changed which species survived in the world's oceans.
+And scientists at James Cook University in Townsville, Queensland and the Field Museum in Chicago warn that modern human-induced changes to the ecosystem could have a similar impact. 
+The researchers report in today's issue of the journal Science how they came across the culling of species while examining figures on the numbers of marine life forms in communities over the past 540 million years. 
+Simple species that did not move or search for food were largely wiped out, they conclude.
+More complex life forms such as crabs and snails that went looking for food took over. 
+The biological devastation occurred when the Earth was believed to have had only one continent, surrounded by a single ocean.
+The researchers did not go into what caused the mass extinction.
+But using a new palaeobiology database, they gave what they say are the most exhaustive details ever assembled of its effect. 
+'Ecologically simple' species such as stationary shells and other forms that filtered food out of the water were replaced by complex communities, mobile species such as crabs and clams.
+"We think these are the first analyses of this type at this large scale," says Dr Peter Wagner, associate curator of fossil invertebrates at the Field Museum and lead author of the study, who worked with Dr Matthew Kosnik of James Cook University. 
+"They show that the end-Permian mass extinction permanently altered not just taxonomic diversity but also the prevailing marine ecosystem structure," Wagner says.
+The results of the study could provide a warning on how we treat the ecosystem now, the experts say.
+"Studies by modern marine ecologists suggest that humans are reducing certain marine ecosystems to something reminiscent of 550 million years ago, prior to the explosion of animal diversity," Wagner says.
+"The asteroid that wiped out the dinosaurs couldn't manage that."
+
+A fraction of the amber collected so far from the beaches of northern Australia
+Huge chunks of amber containing the remnants of ancient rainforests have been found along beaches in Far North Queensland, the first amber fossils to be found in Australia.
+The amber pieces, some as big as a football, contain flies, beetles, spiders, flowers, fungi, moss, fern spores and pollen as well as bubbles of gas and water from the time, the researchers say.
+The fossils are at least 4 million years old, they say, possibly much older.
+Fisherman Dale Wicks and partner Beth Norris discovered the amber while taking evening walks along the beach on the Cape York Peninsula, says University of New South Wales palaeontologist Henk Godthelp.
+"It turns out that it was the very first discovery of true amber in Australia," says Godthelp, who was invited to analyse the fossils and reported the find at the Riversleigh Society meeting in Sydney this week.
+While amber-like substances such as copal and coal resin are found in Australia, no-one had found true amber, he says.
+Godthelp, who studies the evolution of rainforests, says the fossilised resin is most likely from kauri pine, which grows in rainforests. 
+He says amber is very good at preserving living creatures trapped inside it because it stops the air from getting to them and also contains chemicals that act as preservatives.
+Anything trapped inside it, he says, will give a unique picture of ancient rainforests.
+This includes insects, which come from the rainforest canopy, and bubbles of water or gas, which he says could provide clues about past climates.
+Nearly one in five of the amber pieces found contain fossils or bubbles of water or gas, says Godthelp.
+"By world standards, that's remarkably high."
+How old?
+Godthelp says he doesn't know how old the amber is yet but it would be at least 4 million years old, possibly much older.
+"We think it's probably Tertiary," he says.
+
+Polonium interferes with the body's ability to repair itself
+Polonium-210, the highly toxic radioactive isotope found in the body of poisoned former Russian spy Alexander Litvinenko is a very rare, exotic material that is difficult to obtain, scientists say.
+The UK's Health Protection Agency says Litvinenko, who died last week in a London hospital, had a significant amount of the radioactive isotope in his body.
+But how it got there and where it came from is a mystery.
+Radiation and chemistry experts say large-scale equipment, such as a nuclear reactor, would be needed to produce sufficient amounts to kill.
+"It is not as simple as the idea that somebody might have broken into a radioactivity cabinet at some local hospital and walked off with some polonium," says Dr Andrea Sella, a lecturer in chemistry at University College London.
+Although scientists would not speculate on the source of the polonium, Sella says Litvinenko's death is not a random killing.
+"This is not a tool chosen by a group of amateurs. These people had some serious resources behind them," he says.
+Polonium is a by-product of uranium that was discovered by Polish chemist Marie Curie in the late 19th century.
+It's a rare but naturally occurring metalloid found in the soil and atmosphere, and even in the human body.
+But at high doses it is highly toxic if ingested or inhaled; it emits alpha particles that can damage the body's tissues and organs.
+"[Alpha particles] are unable to penetrate a sheet of paper and so it is not a hazard unless ingested," says Professor William Gelletly of the University of Surrey.
+Long-term exposure to radiation can cause mutations and cancer. But exposure to a short, intense burst of radiation causes major damage to key control centres in cells.
+"An alpha particle strikes a strand of DNA. It snips it in two, which is bad news, or glues two strands together. Either way normal cell repair mechanisms may be unable to sort that out," says Sella.
+"The result is that essentially the cellular command and control network [in the body] falls apart. That is what radiation sickness is all about."
+Professor David Ray, of the University of Nottingham, says even if a high dose of radiation could not be detected externally after Litvinenko was admitted to hospital a fatal dose could have concentrated in deep tissues such as bone marrow.
+"The limited information that has been released about Mr Litvinenko's condition and the timing of his death is consistent with either radiation poisoning or chemicals that stop cell division," he says.
+Polonium-210 also has a very short half-life of 138 days, at which point it loses half of its radioactivity.
+"That is long enough so you can handle it and deliver it to your target and it will pack a punch," Sella says.
+Polonium-210 is used in research and medicine, as well as a heating source for space components.
+But in those forms it is not conducive to easy poisoning, scientists say.
+
+Compounds isolated from mangoes could be used to treat metabolic disorders, early research suggests
+A mango a day may one day protect against diabetes and high cholesterol, a preliminary study suggests.
+The study is analysing how individual components of the luscious summer favourite affect human cells.
+And early results, presented at the Australian Health and Medical Research Congress in Melbourne this week, suggest that some mango components act on the same pathways that diabetes and cholesterol drugs target.
+University of Queensland PhD student Ashley Wilkinson says the study, the first of its kind, aims to find unique ingredients in mangoes and other tropical fruit like paw paws.
+"There's been a lot of research looking at nutritional bioactives but it's focused on more temperate fruit and vegetables like broccoli and grapes. And there hasn't been any research looking at tropical fruit in the context of looking at modulating cellular processes," she says.
+Dr Sarah Roberts-Thomson of the university's school of pharmacy, who is supervising the work, says early results suggest some compounds in mangoes work by activating or inhibiting groups of receptors known as peroxisome proliferator-activated receptors, or PPARs.
+"We don't know yet how the whole thing's going to play out but we know some of the individual components activate these receptors or even inhibit them," she says.
+"That could end up with positive nutritional health benefits for diabetes and high cholesterol."
+PPARs are also increasingly being linked to colon and breast cancer, and the study will investigate whether compounds in mangoes can also kill cancerous cells. 
+One of the compounds the researchers are focusing on is quercetin, a chemical also found in onions.
+Another is norathyriol, a by-product of mangiferin, which is found in a range of fruits and traditional antidiabetic herbs.
+Gut bacteria convert mangiferin into norathyriol, Wilkinson says. Once converted, it appears to have an even more potent affect on PPARs.
+Preliminary findings also suggest that mango skin, often a component of mango juice, is particularly rich in these compounds, Roberts-Thomson says.
+A long way down the track these compounds could be isolated to form alternative treatments for metabolic disorders like diabetes and high cholesterol, she says.
+The study is being conducted with the Queensland Department of Primary Industries.
+
+The real-life study found clubbers were using much higher doses of MDMA than lab studies could ever test
+The idea of being followed around a nightclub by a researcher bent on taking a blood sample and measuring your temperature may not be your idea of a good time.
+But 'field' studies like this may be the only way to get the full picture of the effects of the drug ecstasy, or MDMA, says University of Adelaide pharmacologist Professor Rod Irvine.
+Irvine, whose unique recreation-setting study of ecstasy was presented at the Australian Health and Medical Research Congress in Melbourne today, says real-life studies of ecstasy paint a very different picture to conventional, controlled, low-dose laboratory studies.
+"I'm not saying that we must go out into clubs and do naturalistic studies and that they're the only things to do, but those sorts of studies must be included in the spectra of what we're doing," he says.
+"People out there will use much higher doses of the drugs than would ever be allowed ethically in a controlled clinical setting.
+"So it gives you the opportunity ... to perhaps pick up data that you could never replicate in a laboratory."
+Taking the lab to the club
+Irvine's study, conducted with the PhD student Kate Morefield, analysed 10 people who took ecstasy in a party setting.
+The subjects, aged around 27, had taken one to five pills.
+Blood samples were collected just before taking the ecstasy and once an hour for the next four hours. Heart rate, temperature and blood pressure was also regularly monitored.
+The study showed that using the drug in a recreational setting produced higher elevations in heart rate, blood pressure and skin temperature than previous laboratory studies had shown.
+The concentration of MDMA, or methylenedioxymethamphetamine, in clubbers' blood also exceeded those reported in clinical research, Irvine says.
+"In recreational settings, individuals experience or tolerate physiological effects of greater magnitude and achieve considerably higher blood concentrations of MDMA ... than those reported in controlled clinical studies," the research, contained in a poster presentation, says.
+For more information about ecstasy and other drugs, see the DrugInfo Clearing House website, run by the Australian Drug Foundation.
+
+Humpback whales have surprisingly complex brains, which raises questions about how these cetaceans evolved
+Humpback whales have a type of brain cell seen only in humans, the great apes, and other cetaceans such as dolphins, US researchers report.
+This might mean such whales are more intelligent than they have been given credit for, the scientists say.
+And it suggests the basis for complex brains either evolved more than once, or has gone unused by most animal species.
+The finding may help explain some whale behaviours, such as intricate communication skills, the formation of alliances, cooperation, cultural transmission and the use of tools, the researchers report in journal The Anatomical Record. 
+Professor Patrick Hof and colleagues from the Mount Sinai School of Medicine in New York discovered a type of cell called a spindle neurone in the cortex of the whale brains.
+They found the cells in areas comparable to where they are seen in humans and great apes.
+Although the function of spindle neurones is not well understood, they may be involved in cognition - learning, remembering and recognising the world.
+Spindle cells may be affected by Alzheimer's disease and other debilitating brain disorders such as autism and schizophrenia. 
+Complex social patterns
+The researches found spindle neurones in the same location in toothed whales with the largest brains, which the researchers say suggests the cells may be related to brain size.
+Toothed whales such as orcas are generally considered more intelligent than baleen whales such as humpbacks and blue whales, which filter water for their food.
+The humpbacks also have structures that resemble 'islands' in the cerebral cortex, also seen in some other mammals.
+These islands may have evolved to promote fast and efficient communication between neurones, the researchers say. 
+Spindle neurones probably first appeared in the common ancestor of hominids, humans and great apes about 15 million years ago, the researchers say. They are not seen in lesser apes or monkeys.
+In cetaceans they would have evolved earlier, possibly as early as 30 million years ago, the researchers say. 
+How did these cells evolve?
+Either the spindle neurones were only kept in the animals with the largest brains or they evolved several times independently, the researchers say. 
+"In spite of the relative scarcity of information on many cetacean species, it is important to note in this context that sperm whales, killer whales, and certainly humpback whales, exhibit complex social patterns that included intricate communication skills, coalition-formation, cooperation, cultural transmission and tool usage," the researchers write. 
+"It is thus likely that some of these abilities are related to comparable histological complexity in brain organisation in cetaceans and in hominids."
+
+The shapes and colours of this abalone shell are governed by genes that are expressed in precise locations beneath its shell
+Scientists have found the genes responsible for the spectacular kaleidoscope of shapes, patterns and colours that are the hallmark of tropical abalone, edible marine snails found in Australia's Great Barrier Reef.
+Researchers say the vibrant range of patterns and colours on their shell mirror the expression of specific genes in the mollusc's mantle, the umbrella of skin just below the shell.
+The international research team publish its findings in the journal BMC Biology.
+All snails have a mantle, which creates their shell. But marine snails don't build their shells from within.
+"Instead they release molecules into the sea water and then pull together things like calcium and chalk from the water [to add to the molecules to create their shells]," says Australian co-author Professor Bernie Degnan, from the University of Queensland.
+"So the beautiful shells you see are actually the product of taking things out of the sea water."
+This combination of secreted molecules and molecules from the sea acts to strengthen the shell.
+Mystery molecules
+The research team was interested in finding out which molecules the marine snail releases through its mantle.
+To do this, they sequenced 530 randomly-selected genes in the mantle tissue of the Haliotis asinina abalone.
+They then collaborated with German colleagues from the University of G&ouml;ttingen to analyse how these genes are expressed.
+The team identified 331 genes that encode proteins expressed in the mantle, a quarter of which are secreted. 
+Each gene is expressed in a specific part of the mantle, with each area responsible for creating a specific shape, pattern or colour on the shell.
+"What happens is that the mantle secretes proteins and somehow these proteins interact with the seawater to make the shell," Degnan says.
+By comparing the abalone DNA sequences with the genome of a related mollusc, the team showed that the genes encoding the secreted mantle proteins are likely to be rapidly evolving.
+
+Australia's free trade deal with the US may mean nanotherapies may be rushed through tests for safety, efficacy and quality, one critic says. But not everyone agrees
+Australia may be forced to rush through inadequately tested and unsafe medical nanotherapies because of its free trade agreement with the US, a health technology regulation expert says.
+Dr Thomas Faunce, a senior lecturer at the Australian National University college of law and medical school, says Australia is obliged under the free trade agreement (FTA) to make innovative pharmaceutical products more readily available.
+Drugs and medical devices using nanotechnology could fall under this banner, he says.
+Faunce, who presented his concerns at the Australian Health and Medical Research Congress in Melbourne today, says as a result of the FTA, the Therapeutic Goods Administration (TGA) may come under pressure to rush trials of new nanotherapies, particulary during preliminary safety, efficacy and quality testing.
+"The main concern is that the FTA puts obligations on the TGA to initiate a discussion [with US authorities] about fast tracking innovative medical products," he says.
+"It's not quite sure exactly what that means but the concern is that we're still in a situation where it hasn't been definitively established that nanotechnology is safe."
+Nanotechnology involves using extremely small particles on the scale of one billionth of a metre.
+In medicine, it could be used to create tiny 'machines' that are introduced into our bodies to deliver medicine, diagnose disease or even fight cancer cell by cell.
+But because the technology is so new there are concerns about its safety, Faunce says. 
+This is because the minute size of the particles means they could evade our normal respiratory and immune defences to enter the lungs or even penetrate our skin.
+There are fears that once in our bodies, nanoparticles could enter our circulatory and nervous systems, potentially becoming lodged in organs including the lungs and brain.
+"Major concern with this unprecedented research and development is that engineered nanoparticles may present unique health risks when used in medical applications," Faunce says.
+"They are highly reactive and mobile within the human body and there are currently no effective methods to monitor exposure risks."
+Is this a problem?
+Monash University's Professor Brian Priestly, director of the Australian Centre for Human Health Risk Assessment, says it's probably true that developments in nanotechnology are happening too fast for the regulators to keep up with them.
+"But that's not to say that it's being ignored," says Priestly, who has worked with the TGA in the past.
+"I know that the TGA looks very carefully at all sorts of innovative technologies so they'll certainly be looking at any developments in anotechnology."
+A TGA spokesperson says rigorous testing is required for all new drug products and nanotherapies are no exception.
+"Extensive, non-clinical, toxicological and clinical safety testing is required for all new drug products," the spokesperson says.
+"No concessions or reductions in these requirements will apply to nanomaterials in therapeutic products."
+The federal government is currently considering the need for a distinct nanotechnology regulatory body and is expected to release a national nanotechnology strategy in coming months.
+
+Honey bees stick out their proboscis when they smell explosives. So could they do sniffer dogs out of a job?
+Bees have been trained to sniff out explosives in a project scientists say could have far-reaching applications for security and the Iraq war.
+Scientists at a US weapons laboratory say they trained honey bees to stick out their proboscis, the tube they use to feed on nectar, when they smell explosives in anything from cars and roadside bombs to belts similar to those used by suicide bombers.
+Researchers at the Los Alamos National Laboratory have dubbed their research the Stealthy Insect Sensor Project. 
+They trained bees to recognise substances by exposing them to the odour of explosives followed by a sugar water reward.
+Among the substances they can sniff are dynamite and C-4 plastic explosives to the Howitzer propellant grains used in improvised explosive devices in Iraq. 
+"When bees detect the presence of explosives, they simply stick their proboscis out," says research scientist Tim Haarmann.
+"You don't have to be an expert in animal behaviour to understand it as there is no ambiguity."
+The findings followed 18 months of research at the Los Alamos facility, the nation's leading nuclear weapons laboratory.
+"We are very excited at the success of our research as it could have far-reaching implications for both defence and homeland security," Haarmann says. 
+While scientists have trained wasps to respond to the trace of explosives, Haarmann says research with bees appeared to show more promise. 
+Haarmann says the bees could be carried in hand-held detectors the size of a shoe box, and could be used to sniff out explosives in airports, roadside security checks, or even placed in robot bomb disposal equipment. 
+He says the next step would be to manufacture the bee boxes and train security guards in their use. 
+"It would be great to start saving some lives with this," he says.
+
+This binary system regularly emits the most energetic gamma rays ever observed. The system consists of a huge star and a compact object, possibly a black hole
+Astronomers have discovered an 'orbital clock' in the Milky Way, a gamma ray source 100,000 times more energetic than any other.
+The repeated emission comes from a binary system where a compact object, possibly a small black hole, orbits a massive star about every 4 days.  
+An international team of scientists reports its findings in the Journal of Astronomy and Astrophysics. 
+Very High Energy (VHE) gamma rays in this system are produced when particles are accelerated to move at close to the speed of light.
+This happens when particles from the strong stellar wind collide with particles from the compact object.
+But the process is reversed when the gamma rays meet the intense ultraviolet light radiated by the star, and are absorbed. 
+It is the production, then absorption, of the gamma rays that is responsible for complex variations in the signal.
+The signal is strongest when the compact object is in front of the star and weakest when it is behind it.  
+"This is the first time we've been able to identify this orbital variation in a high energy gamma ray source and it allows us to probe to much greater depth the astrophysics of gamma ray production and absorption," says Australian co-author Dr Gavin Rowell from the University of Adelaide. 
+Neither the production nor the absorption processes are well understood. VHE gamma ray emission is rare and the object is one of just 30 such sources discovered in the past few years.
+It is also the only one where the intensity of the emission changes in a regular fashion.
+Rowell says a number of factors are involved in the signal's periodic patterns.
+These include geometric effects relating to the orientation of the compact object to the star and the angle at which the system is seen from Earth.
+"There is lots of interaction between events which leads to the flux profile we see.  The rules are quite simple but separating the influences of changes in the magnetic field, the intensity of the stellar wind and mechanisms contributing to particle acceleration and absorption is difficult," Rowell says.
+"Orbital signatures like this are useful keys. They act as a probe of the changing environment as the compact object moves along its orbit and give a useful insight into how gamma rays are produced and what happens to them."
+The source was detected as part of a survey of VHE gamma ray sources in the southern sky using the most sensitive ground based gamma ray detector, the High Energy Spectroscopic System in Namibia, southwest Africa.
+
+The Antikythera Mechanism was so advanced in its mathematics and technology that the history of Ancient Greece may have to be rewritten
+A 2100 year old clockwork machine whose remains were retrieved from a shipwreck more than a century ago has turned out to be the celestial supercomputer of the ancient world.
+Scientists used 21st century technology to peer beneath the surface of the encrusted gearwheels of the so-called Antikythera Mechanism, made by the Ancient Greeks.
+The researchers were stunned to find it could predict the ballet of the Sun and Moon over decades and calculate a lunar anomaly that would bedevil Isaac Newton himself. 
+And nothing as complex was built for at least a thousand years, say the researchers, who publish their results today in the journal Nature.
+"It's beautifully designed. Your jaw drops when you work out what they did and what they put into this," says astronomer Professor Mike Edmunds of Cardiff University.
+"It implies the Greeks had great technical sophistication."
+The Antikythera Mechanism was built in Greece around 150-100 BC and may be linked to the astronomer and mathematician Hipparchos.
+But the machine did not surface until 1901 when Greek divers, who were exploring a Roman shipwreck, found 82 curious bronze fragments.
+At first, these pieces, thickly encrusted and jammed together after lying more two millennia on the sea floor, lay forgotten.
+But a closer look showed them to be exquisitely made, hand-cut, toothed gearwheels. 
+The 29 gearwheels fitted together, possibly making some sort of astronomical calendar. But of what, exactly? 
+The mystery unfolds
+For a quarter of a century, the textbook on the strange find was a work written by a historian of science and technology, Professor Derek de Solla Price of Yale University.
+He hypothesised that the machine in fact had 31 gearwheels, and did something pretty astonishing. 
+It linked the solar year with a 19-year cycle in the phases of the Moon. This is the so-called Metonic cycle, which takes the Moon 235 lunar months to the same phase on the same date in the year.
+Edmunds' team, gathering experts from the UK, Greece and the US, has now taken the tale several chapters forward.
+21st century techniques
+They used 3D x-ray computation tomography and high-resolution surface imaging to peek beneath the machine's surface, yet without damaging the priceless artefact.
+There, they read inscriptions on the bronze cogs that had been unseen by human eyes since that Roman ship came to grief aeons before. 
+The original device, they believe, is likely to have had 37 gearwheels and two clock-like faces, one front and one back.
+It would have fitted into a slim wooden box measuring 31.5 x 19 centimetres, which was 10 centimetres thick. 
+The machine was a 365-day calendar, which ingeniously factored in the leap year every four years. 
+It not only provided the Metonic cycle, which was known to the Babylonians, it also gave the so-called Callippic cycle, which is four Metonic cycles minus one day and reconciles the solar year with the lunar calendar. 
+It could also predict lunar and solar eclipses under the Saros cycle, a 223-month repetitive interplay of the Sun, Earth and Moon.
+This function, presumably, would been useful for religious purposes, given that eclipses are traditionally taken as omens. 
+The machine was also a star almanac, showing the times when the major stars and constellations of the Greek zodiac would rise or set and, speculatively, may also have shown the positions of the planets. 
+Lunar anomaly
+But even more impressive is a tiny pin-and-slot device that factors in a movement of the Moon that, for centuries, puzzled sky-watchers. 
+In this so-called main lunar anomaly, the Moon appears to move across the heavens at different speeds at different times, the reason being its elliptical orbit around Earth.
+"Newton used to say he would think about this until his head hurt," says Edmunds. 
+This latter discovery prompts the scientists to wonder if the great Hipparchos, who drew up the first catalogue of the stars and wrote about the lunar anomaly in the 2nd century BC, may have had a hand in designing the mechanism. 
+Adding circumstantial evidence to this theory is that the shipwreck was found to have jars and coins from Rhodes, where Hipparchos lived. 
+The computer is so advanced in its mathematics and technology that the history of Ancient Greece may have to be rewritten, says Edmunds. 
+"We now must ask: What else could they do? That's a difficult thing, because this is really the only surviving metallic artefact of its kind. Who knows what else may be lost?" 
+Islamic science
+It was not until the end of the first millennium AD and the golden age of Islamic science that anything so technologically wondrous surfaced again, if the archaeological evidence is a guide. 
+This was an eight-geared astrolabe, depicting the movements of the Sun and Earth, by the Islamic astronomer al-Biruni in 996 AD. 
+Had the Greeks' knowledge somehow survived and been transmitted across the centuries, to inspire al-Biruni?
+Or had it withered away and disappeared, leaving Islamic scholars with the task of rediscovering what had been known 1000 years before?
+
+Some scientists believe that the diversity of early Australians is explained by there being more than one founding population. But not everyone agrees
+New genetic evidence suggests Australia may have been populated by two separate groups of humans, one arriving via Papua New Guinea, the other via Indonesia, a researcher says. 
+But more work is needed to confirm the idea. And not all scientists agree that these latest results shed new light on the long-standing debate on how humans colonised Australia.
+Dr Sheila van Holst Pellekaan, a molecular anthropologist from the University of New South Wales in Sydney, will present her research at a Australian Archaeological Association conference in Melbourne next month.
+Previous genetic analysis shows that modern humans took two migration routes out of Africa 100,000 to 150,000 years ago, she says.
+One group went north into Europe and Northern Eurasia, the other along the coast via Saudi Arabia, India and Southeast Asia.
+Van Holst Pellekaan analysed mitochondrial DNA (mtDNA) from Aboriginal people in western New South Wales and Central Australia.
+She says she found evidence of two ancient genetic groups that appear to be linked to these two migration routes.
+Van Holst Pellekaan says some archaeologists argue there was more than one founding population of Australia and her research is the first genetic evidence that could be used to support this. 
+It's possible that some Australians came in from the north via Papua New Guinea and the other took a more southerly route via Indonesia, she says.
+Different views
+Archaeologist Dr Colin Pardoe, who is speaking at the conference on a related topic, disagrees.
+He believes the diversity of early Australians could have arisen from one group that came in from Southeast Asia and then diversified as it adapted to different environments.
+Pardoe is not convinced van Holst Pellekaan has identified two founding groups.
+"Are these two totally distinct groups that came in or are they representatives of one major group that came in that has all that diversity within it?" he asks.
+This is a possibility that van Holst Pellekaan accepts.
+"The idea of two founding populations is speculative," she says. "I can't prove it either way." 
+Pardoe says more DNA samples from other places such as the Indonesian islands and Papua New Guinea would need to be analysed.
+"We need to understand the pattern of variation in these large groupings to see where Australians are coming from," he says.
+Professor Peter Brown of the University of New England in Armidale also says further data is required, including studies of Y chromosome DNA, as mtDNA only reflects the maternal line.
+Van Holst Pellekaan says some Y-chromosome studies of Aboriginal people from Central Australia have found a connection with India, but there have been no comprehensive studies of this type.
+Genetics reflects long Aboriginal history
+Van Holst Pellekaan says despite the links with the global lineages that came out of Africa, the Australian groups are quite different from those shown in samples from Papua New Guinea, the Andaman and Nicobar Islands and Malaysia.
+"[People] have to have been in Australia for a very long time for that diversity to generate. We're saying at least 40,000 years," she says.
+Van Holst Pellekaan accepts the idea of tracing Aboriginal people back to Africa can clash with some cultural beliefs, which she respects.
+"I simply present it to them as a scientist's way of seeing how the language groups might have related to each other," she says.
+"I can only give them the information I come up with. I don't ask them to believe it."
+
+Spider monkeys chew fragrant plants and 'anoint' themselves with the smelly mash. But no-one is sure why
+What may be the most natural cologne in the world was recently discovered in a Mexican forest. The ingredients? Monkey spit and chewed up leaves.
+According to a paper in the journal Primates, male Mexican spider monkeys chew the leaves of three aromatic plants: the Alamos pea tree, which has fragrant leaves and flowers, a flowering trumpet tree, and wild celery. 
+Matthias Laska, a professor of zoology at Link&ouml;ping University in Sweden calls the ritual, which typically takes anywhere from 30 seconds to 2 minutes, monkey "self-anointing".
+Laska and his colleagues observed the behaviour 20 times in two male spider monkeys that were part of a free-ranging group at the Parque de Flora y Fauna Silvestre Tropical in Veracruz, Mexico. 
+The researchers determined the monkeys always applied just one plant species at a time. The application was routine, not unlike a man who regularly squirts on deodorant or cologne.
+"In the majority of cases, the arm that did not hold the scent-bearing material was held high or grabbed a branch above the animal," Laska and his team write.
+While this is the first reported case of such behaviour in wild Mexican spider monkeys, similar routines have been spotted among both male and female capuchin monkeys, owl monkeys, other spider monkeys and lemurs. 
+In most of these cases, the scientists speculate that the leaf mash might have been used to mitigate topical skin infections or repel bugs.
+But Laska and his team found that of the plants used by the Mexican spider monkeys, only wild celery is known to have insect-repelling compounds and antifungal properties. The other plants simply smell good.
+The scientists, therefore, conclude that self-anointing "may play a role in the context of social communication, possibly for signalling of social status or to increase sexual attractiveness". 
+In other words, monkeys could do it for the same basic reasons people use cologne.
+Chemistry still a mystery
+While the chemistry behind this remains a mystery, the odours may mimic those of fragrant, naturally occurring primate steroids, which are presumed to act as sex-stimulating pheromones.
+Laska conducted an earlier study that found spider monkeys are particularly gifted at sniffing out such scents.
+But not all monkeys want to smell like flowers and celery.
+Dr Mary Baker, assistant professor of anthropology at Rhode Island College, has observed capuchin monkeys applying citrus and tobacco leaf mashes to their bodies.
+Dr Christina Campbell, a scientist at the Cotsen Institute of Archaeology at the University of California at Los Angeles, observed the same behaviour in black-handed spider monkeys in Panama.
+"In general, I agree with the [new] findings," says Campbell. But she hasn't yet ruled out other possible reasons for scent rubbing.
+"I think the behaviour may be some kind of signalling, although I am not convinced," she says.
+"I also wonder whether it may function to stimulate or clean the gland that they rub the plant mixture on."
+Laska hopes future studies will resolve such questions about the fragrant ritual.
+
+Children may have permanent brain damage after chemotherapy, experts say 
+Chemotherapy damages brain cells, according to two studies published this week, leading to memory loss and confusion in cancer patients, and possibly permanent damage in young children.
+Cancer patients have long complained of 'chemobrain', a nickname for loss of memory and inability to solve problems and in general think clearly often seen after chemotherapy.
+While the effects may wane in adults after a few years, one expert points out that the effects may be more permanent in children with growing brains.
+Dr Masatoshi Inagaki of the Breast Cancer Survivors' Brain MRI Database Group in Japan and colleagues tested more than 200 breast cancer patients, some who had chemotherapy along with surgery and some who did not.
+They used magnetic resonance imaging, or MRI, to take detailed pictures of the patients' brains one and three years after treatment. 
+A year after 51 patients had chemotherapy, the researchers found significant regions of the brain were smaller, notably those important to cognition. 
+Cognition includes learning, some types of memory and the ability to understand the surrounding world clearly. 
+But in 73 patients screened three years after chemotherapy, there were no such differences, Inagaki's team reports in the journal Cancer.
+"Results lead to the idea that adjuvant chemotherapy could have a temporary effect on brain structure," the researchers write. 
+"These findings can provide new insights for future research to improve the quality of life of cancer patients," they add.
+Deadly damage
+A second study shows that drugs used to treat cancer may damage normal, healthy brain cells more than the cancer cells they are meant to target. 
+Dr Joerg Dietrich and colleagues at the University of Rochester in New York worked with human brain cells in lab dishes.
+They exposed them to common chemotherapy drugs such as cisplatin, carmustine and cytarabine. They also soaked cells from real human tumours in the drugs. 
+The drugs killed more brain cells than tumour cells, they report in the Journal of Biology.
+Low doses of the chemotherapy drugs killed 60-90% of brain cells called oligodendrocyte precursor cells and neurone precursor cells, but had little effect on most of the cancer cells.
+To kill 80% of cancer cells, doses that killed 70-100% of the brain cells were required.
+When they treated live mice with the drugs, Dietrich's team found that brain cells in the mice continued to die for at least six weeks after the end of treatment.
+Straight to the head
+Dr Patricia Duffner, a neurologist at the University of Buffalo School of Medicine in New York, says radiation therapy on the head has long been known to affect intelligence. 
+"Cranial irradiation can be so devastating to the brains of young children [under three to five years] that, by the mid-1980s, many families opted not to treat babies and very young children who had malignant brain tumours," she writes in a commentary in the same journal.
+"Very high-dose chemotherapy, requiring bone marrow transplantation or peripheral stem cell support, is now standard therapy for children with certain brain tumours, especially for the very young," she adds.
+"There are no easy answers. We must balance the need for survival with quality of life."
+
+The Ngarrindjeri people put the repatriated remains of their ancestors to rest. Image used with permission from the Aboriginal community
+Aboriginal human remains stolen in the name of science are being reburied in traditional burial mounds using the latest technology to ensure that existing burials are not disturbed.
+The reburial project, involving the Ngarrindjeri people of South Australia, will be discussed at the Australian Archaeological Association Conference in Melbourne next week.
+Members of a thriving medical research community took Ngarrindjeri human remains during the 19th century and as late as the 1950s, says Flinders University archaeologist Dr Lynley Wallis, who is helping with the project.
+She says literally thousands, if not tens of thousands, of bodies were removed.
+"People were stealing bodies from graves around Adelaide," she says, adding that many traditional burial mounds were in sand dunes, which made it particularly easy for bodies to be taken.
+"Sometimes it was within days or weeks [of burial]," she says. "Worse than that, they were being taken out of the morgue in Adelaide."
+Remains were sent to places such as the British Museum and the Museum of Edinburgh in the UK, as well as the South Australian Museum and Museum Victoria in Australia, says Willis.
+In 2003, the Museum of Edinburgh became the first to repatriate the remains of more than 300 Ngarrinjeri people.
+Remains were not always complete sets of bones, she says.
+"Sometimes it might be an organ in a jar. Sometimes it's a skull, sometimes it's a leg bone."
+Some remains were up to 2200 years old, she says, and many of them had never been examined.
+Voices of the Aboriginal community
+Wallis is keen to emphasise she cannot speak on behalf of the Ngarrindjeri community, representatives of which were not immediately contactable.
+But in an interview last year with a Flinders University researcher, chair of the Ngarrindjeri Heritage Committee, Uncle Tom Trevorrow, explained the need for reburial ceremonies for the repatriated remains of Old People, the term of respect used when referring to ancestors.
+"We're forced to do a repeat of a funeral ceremony because other people have gone in and taken our Old People's bodies without listening to us or getting our permission," he said.
+"We don't know what those Old People have been through, we don't know what they've done to them."
+The customary burial ceremony involves smoking bodies to allow their spirits to travel and to be at rest.
+Once disturbed from their resting places, this ceremony needed to be carried out again, Uncle Tom said.
+Role of the archaeologists
+Using the limited paperwork accompanying the remains, the Ngarrindjeri community has been identifying which burial mounds they were taken from.
+"If they come from the river that's their country ... if they come from the lake that's their group," said Uncle Tom.
+The first reburial took place at Hack's Point on 23 September this year.
+To make sure they didn't disturb people and cultural objects already buried in the mounds, the community called on Wallis and others to help.
+"The last thing they wanted to do was to disturb existing burials," says Wallis.
+The team used various geophysical techniques to work out which areas in the burial mound they could dig up safely.
+This is the first time such technology has been used for Indigenous reburials in Australia, says Wallis.
+The researchers used a magnetometer to detect the mineral maghaemite, which could have formed from fires used during ceremonies.
+The team also used electromagnetic induction that detects changes in moisture and conductivity of sediments that occur when ground is disturbed.
+By combining the results of the two surveys the team identified a location in the burial mound where there had been no disturbance.
+The remains of 23 people repatriated from the Museum of Edinburghwere reburied in the first ceremony.
+"Thankfully our science worked and we didn't hit any existing burials," says Wallis.
+Signs from the ancestors?
+Wallis says the day before the first reburial a storm blew up over nearby Kangaroo Island, which Ngarrindjeri people call the "island of the dead", where spirits go after people have been buried.
+They thought this was the old people stirring because they knew something was about to happen, says Wallis.
+On the day itself, a large flock of pelicans flew over the burial ceremony, says Wallis who was present at the reburial.
+Pelicans, known as ngori, are a totem for the Ngarrindjeri people and the flock were seen as the spirits of the old people coming to see the burial, says Wallis.
+"It was so amazing, these huge flocks flying in formation. If you didn't believe in Indigenous connection to country, after going through that process you certainly would have."
+
+Nanoparticles are already used in consumer products including toiletries
+Fears about nanotechnology may be overblown, says an Australian expert in toxicology and environmental health.
+Monash University's Professor Brian Priestly, director of the Australian Centre for Human Health Risk Assessment, says we need to put fears about the potential health risks of nanoparticles into perspective.
+Priestly was among a number of nanotech specialists who spoke about nanotoxicology at the Australian Health and Medical Research Congress in Melbourne this week.
+"I'm not saying that we don't have knowledge gaps that we have to fill," he says. "But some of the statements that are being made I think are extreme."
+The federal government is expected to release a national strategy on nanotechnology in the coming months and is considering whether an independent regulator should be established to oversee this rapidly advancing field.
+Priestly says it's unlikely that members of the general public will be exposed to nanoparticles.
+"What we have to ask is what are the chances that we will be exposed to these very fine manufactured nanoparticles, because risk is really a function of toxicity and exposure," he says.
+"These things may have slightly higher grades of toxicity than larger particles but a lot depends upon whether we're exposed to them and how we're exposed to them.
+"If they get into the air and we inhale them, yeah, they're likely to present the same sorts of risks we have with other types of air pollution of very fine particles."
+He also says the majority of nanoparticles will be safe because they're fixed in surface coatings.
+Dr Kelly BéruBé, a lecturer in cell biology at Cardiff University in Wales, has been studying nanosized products of combustion like soot and coal ash as a model for engineered nanoparticles.
+She says human have been exposed to these particles for as long as we have been burning things, and it's known they can cause inflammatory responses and cardiac problems.
+She says these are the sorts of particles we should be worried about, rather than engineered nanoparticles.
+"These are the ones that everybody's exposed to every day. It's highly unlikely that the average person like you or I is going to be exposed to any of these engineered ones," she says.
+Uses of nanoparticles
+Nanotechnoloy involves the manipulation of atoms and molecules for uses in medicine, research, computing and the creation of new types of materials and surfaces.
+Nanoparticles are already used in a wide range of commercially available products including sun screens, cosmetics, shoe polish, crayons and even tennis racquets. 
+The federal government says it has been assessing therapeutic products containing nanotechnology components for many years.
+"Fumed silicon dioxide nanoparticle aggregates for example, have been use in food, cosmetics and pharmaceuticals for about half a century and carbon black nanoparticles have been used in rubber products for more than a century," a health department spokesperson says.
+Sunblock creams using zinc oxide and titanium dioxide nanoparticles are also being manufactured in Australia.
+Red flags
+But Dr Paul Wright, associate professor in immunotoxicology at RMIT University and director of the research network Nanosafe Australia, says rapid recent developments highlight the need for caution.
+He says engineered nanoparticles have unique and properties compared to the sort of particles BéruBé has been looking at.
+"These are derivitised, these are functionalised nanoparticles, they can have totally unknown effects on the biological system," he says.
+Dr Sam Bruschi is a consultant in medicinal chemistry, who recently finished a review of nanotech safety issues for the Australian Safety and Compensation Council.
+He says the little that we do know about the health impact of nanotechnology has raised some red flags.
+He says animal studies have found pre-cancerous lesions like fibrosis and granulomas in mice that have had carbon nanotubes aspirated into their lungs. 
+Tumours associated with titanium nanoparticles, which are used in sunscreen, have been found in research animals, he says. And in the lab, "quantum dots kill cells quite happily".
+"There are some smoking guns out there and all we have to do is find the bullets," he says.
+Because of their size, nanoparticles can evade the body's normal respiratory and immune defences and once inhaled or absorbed through the skin, potentially finding their way into the nervous and circulatory systems and becoming deposited in organs including the brain.
+Much of the concern has also focused on carbon nanotubes, because of fears they are the right size and shape to act like deadly asbestos fibres.
+Jury's out
+BéruBé says until we have microscopes powerful to actually track where nanoparticles are going in the environment and in our bodies, and what they actually do there, the jury must remain out about any pending health catastrophe.
+"We don't have the technology there to see exactly what these particles are doing, so we can't tell you exactly what the health impacts will be," she says.
+"Unregulated use [of nanoparticles] could open society up to the asbestos of the 20th century.
+"But we've been living with [combustion-derived nanoparticles since caveman times and we've learned to adapt to it."
+
+We may soon be getting weather reports from Mars without sending probes into space. And scientists say an old way of gathering data may do the trick
+Astronomers have shown that an old technique for mapping the topography of Mars from Earth could be used in a novel way to map the Red Planet's weather. 
+The thin atmosphere on Mars consists almost entirely of carbon dioxide.
+And before spacecraft images revealed the planet's surface features, astronomers tried to use variations in the density of carbon dioxide to map the topography, with mixed results.
+Now preliminary ground-based images of Mars taken in the near infrared region of the spectrum, which is most sensitive to carbon dioxide, have revealed interesting surface features.
+These show remarkable agreement with the accurate topographical data obtained from the Mars Orbiting Laser Altimeter aboard the Mars Global Surveyor. 
+The density of carbon dioxide also indicates the atmospheric pressure at the surface, which is subject to huge seasonal variation as carbon dioxide readily transports from one pole to another.
+So PhD candidate Sarah Chamberlain from the Australian Centre for Astrobiology at Macquarie University says the technique could be now be used for remotely sensing changes in atmospheric pressure in the Red Planet's dynamic weather system.  
+"Since we now have an accurate topographic map of the Martian surface, we can use the technique to look for variations from the topography to indicate regions of high and low pressure," she says.  
+This will provide a pressure map that will help with understanding weather patterns through seasonal changes across the planet.  
+"Weather is important to understand on Mars for landing spacecraft and looking at the atmospheric dynamics on other planets," says Chamberlain. 
+Measurements of the surface pressure distribution on Mars provide the key data needed for testing general circulation models of the Martian atmosphere.
+The only pressure measurements that have been made so far are from the Viking landers in 1976 and later the Pathfinder Rover, which cannot give a global picture of the Martian atmosphere.
+Chamberlain is co-author of a paper in the latest Publications of the Astronomical Society of Australia, which suggests that until a network of surface stations can be established on Mars, remote-sensing techniques such as the one demonstrated will provide the only way of obtaining such data.
+
+Criminal psychopaths might not stop their attacks because they may have learned to dampen their brain's response to other peoples' distress signals
+A biological defect in the way blood flows in the brain rather than a psychological defect could be one reason why some people become criminal psychopaths, a new study shows. 
+Researchers from the Institute of Psychiatry at King's College London monitored the emotional responses of six men who had committed repeat offences such as attempted murder, rape with strangulation and grievous bodily harm. 
+All six subjects scored highly on the Hare Psychopathy Checklist, a test that looks for the presence of cunning, manipulative or exploitative behaviours as well as lack of guilt or remorse.
+It is thought that people with psychopathic disorders lack empathy because they cannot process when someone is distressed, for instance a face that looks scared.
+To test this, the people in the study were shown images of fearful, happy and neutral faces.
+Their brains were then imaged with functional MRI, a type of brain scan that shows which parts of the brain 'light up' in response to these images.
+Their brain scans were then compared to those of healthy control subjects. 
+"We've never been able to look directly in the brain before and what we found is that when psychopaths were exposed to frightened faces the distress cue didn't increase the psychopath's blood flow. It decreased it," says author Professor Declan Murphy.
+He adds psychopaths might not stop their attacks because they may have learned to dampen their brain's response to other peoples' distress signals. 
+Tom Fahy, professor of forensic mental health and co-author of the study, which is published in the latest issue of the British Journal of Psychiatry, says criminal psychopathy may be inherited or acquired through very deprived and abusive childhoods.
+He adds the findings of the study open possibilities for new treatments other than counselling therapies and could be used to identify people who had a higher risk of re-offending. 
+"Psychopaths currently respond pretty poorly to treatment but this biological problem could be used as a marker for people who say they have recovered but actually haven't," Murphy says.
+
+The future is nuclear, says a new report into Australia's rich uranium resources
+New nuclear technology will cut waste so significantly that we may no longer need to dump it underground, according to an Australian government report.
+The report, tabled in parliament this week, also says Australia should lift restrictions on uranium exploration, mining and export because at present nuclear power is the only "reliable and proven" way of cutting greenhouse gas emissions.
+"Advanced nuclear reactors and spent fuel reprocessing technologies are now being developed which will significantly reduce the quantity and toxicity of nuclear waste," says the report, Australia's uranium - greenhouse friendly fuel for an energy hungry world.
+"These technological advances could potentially obviate the need for geological repositories altogether."
+The new generation of reactors could also reduce the isolation period needed for waste to "just a few hundred years".
+But Dr Mark Diesendorf of the Institute of Environmental Studies at the University of New South Wales, has dismissed these comments as "propaganda for the nuclear industry".
+He says the 440 nuclear reactors operating around the world today are "almost identical" to those of 25 years ago.
+"This is speculation about future reactors that are not on the market," he says of comments made in the report.
+Reducing waste
+Nuclear waste consists of spent uranium, plutonium and other by-products, which critics like Diesendorf say needs to be managed for up to hundreds of thousands of years.
+Professor Stephen Lincoln, an expert in nuclear energy and uranium from the University of Adelaide, says it's possible to recycle some of this waste by turning it into a mixed uranium-plutonium oxide, or MOX.
+"So instead of just using uranium oxide in the fuel rods you use mixed uranium and plutonium. That burns up the plutonium but it also produces nuclear power," he says.
+Professor Leslie Kemeny, Australian foundation member of the International Nuclear Energy Academy and a consultant nuclear physicist, says three reactors around the world are already using this so-called MOX.
+Kemeny says we'll also get better at developing ways of using waste from nuclear reactors, not only as an energy source but for use in industry and hospitals.
+"I firmly believe ... everything that is taken out of the reactor core to be put into a waste depository is highly valuable," he says.
+Improving safety
+Kemeny says new technology will not only cut back waste, but will make nuclear reactors safer.
+He says pebble-bed reactors are being developed that package the uranium in graphite balls rather than iron rods, making waste easier to handle.
+"With the generation IV reactors you will go for a fuel element that is enriched particles of uranium interspersed with silicon and carbon in a small ball or hexagonal shaped fuel element," he says.
+"You can circulate these balls in and out of the reactor or just drop in a set of orange-sized or tennis ball-sized and take out ones that have been there a long time."
+And because pebble-bed reactors are cooled by gas like helium or carbon dioxide they reduce the risk of overheating and a Chernobyl-style meltdown, he says.
+But Deisendorf says according to his calculations pebble-bed reactors would produce 13 times more nuclear waste than conventional ones.
+"You don't have rods but you have 13 times the quantity of nuclear waste because you're embedding the fuel in pebbles, and the pebbles occupy a lot of volume and it all becomes highly radioactive," he says.
+Lincoln says while pebble bed rectors are "fine in principle", none are currently being used to generate power and the fuel is more expensive to produce.
+"When you bring in any new technology it's got to be proved and tested and the final analysis is, is it commercially competitive in terms of producing electricity by comparison with the currently used reactors?" he says.
+Lincoln says no degree of technological sophistication will ensure 100% safety at nuclear reactors and adds it's difficult to imagine a reactor so advanced that it produces no waste at all. 
+"It's true that modern reactors are better in that respect, they produce less waste. But they're always going to produce it," he says.
+"It's still quite a significant issue because at this point in time there is not one single permanent storage for high-level nuclear waste."
+
+Reef sharks in Australia's Great Barrier Reef are being fished to the brink of extinction, a new report suggests
+Southeast Asia's voracious appetite for shark fin soup may be contributing to a dramatic drop in the number of reef sharks in Australia's Great Barrier Reef, a marine scientist says.
+Dr Sean Connolly and colleagues from James Cook University found a 10-fold decrease in shark numbers in areas where fishing is allowed after conducting the first shark census in the World Heritage listed area.
+The study, published in the latest issue of the journal Current Biology,  looked at two species of shark, the grey reef shark (Carcharhinus amblyrhynchos) and the whitetip reef shark (Triaenodon obesus).
+The sharks were observed across four fishing management zones, ranging from strict no-entry to open fishing.
+"We found [where fishing is strictly banned] shark numbers are 10 times higher than in zones where there is fishing," Connolly says.
+"We can see that the populations are severely depleted already but we also have projections that say that those declines are ongoing and quite rapid." 
+The study sent out divers to count shark numbers as well as using mathematical modelling taking into account births, deaths and population growth patterns.
+It found whitetip reef sharks are declining at an average rate of 7% a year with a 17% rate of decline for grey reef sharks. 
+The study predicts that if the trend continues populations will drop to 5% and 0.1% of what they would be without fishing.
+Shark fin soup
+Conolly says the results show that fishing is threatening reef sharks with ecological extinction, where their numbers will be so small they will no longer play a role in the marine ecosystem.
+Some overfishing could be driven by the international market for shark fins, he says.
+People fishing in certain areas of the reef are able to catch sharks and sell their fins separately, although they must bring back the carcass.
+"There probably is some selling of shark fin to the international market and that pressure is likely to increase as the price for fins goes up, because there will be growing demand and an increasingly depleted shark populations," Connolly says.
+Sharks are also often viewed as a pest by anglers looking for other game, such as coral trout, he says. Or they could be caught by accident.
+"One of the main causes of decline in sharks is because they are what's called a bycatch species, which means you catch them by mistake when you're trying to get something else," he says.
+Total landings of all shark species on the Great Barrier Reef have increased about four fold in the past 10 years, Connolly says.
+Impact on the reef
+Sharks sit at the top of the reef food chain but Connolly says it's hard to predict exactly how their loss would affect the coral reef ecosystem.
+"Some modelling suggests that removing sharks can erode the resilience of coral reefs because if you take sharks out the smaller predators in the system could increase in number, and that could potentially decrease number of grazing seaweed eating fish," he says.
+The study concludes that "immediate and substantial" reductions in shark fishing are needed for reef populations to recover.
+
+A base on the Moon would be used to test technologies needed for future trips to Mars
+The US space agency says it plans to build a permanently occupied base on the Moon, most likely at its south pole. 
+The base will serve as a science outpost as well as a testbed for technologies needed for future travel to Mars, NASA says.
+Construction will follow a series of flights to the Moon scheduled to begin by 2020.
+"We're going for a base on the Moon," says Dr Scott Doc Horowitz, NASA's associate administrator for exploration from the Johnson Space Center in Houston.
+Plans for what the base will look like and what astronauts would do there have yet to be determined.
+Similarly, NASA has not projected a date when the base would go into operation. 
+The Moon's polar sites are preferred to equatorial regions because of more moderate temperatures and longer periods of sunlight, which is critical for the solar-powered electrical systems NASA plans to develop.
+Eventually, nuclear power may be used to augment or replace the solar energy systems. 
+Scientists also suspect the poles have resources such as hydrogen, ice and other materials that could be used to support life. 
+"It's exciting," says NASA deputy administrator Shana Dale. "We don't know as much about the polar regions."
+The US has already announced plans to develop new spacecraft to travel to the Moon and land on its surface for the first time since the last Apollo flight there in 1972.
+It also plans to provide a communications system linking Earth and the Moon. 
+But NASA doesn't plan to go to the Moon alone. The US will look for international and commercial partners to share the expense and possibly provide components such as additional power systems, living quarters and resources for lunar surface travel. 
+NASA is not expecting a budget increase to pay for the program. Rather, it will transition funds currently being used to support the space shuttle into the Moon exploration program as the shuttle fleet is phased out. 
+The shuttles are set to be retired in 2010. By that time, NASA plans to have finished building the space station, leaving the Moon initiative as a successor to both programs.
+
+Earthquakes and crystallising lava are clues that volcanoes are about to blow, new research shows
+Better predictions of when volcanoes are going to erupt may be possible with a new computer model developed by Australian scientists.
+Dr Alina Hale from the Earth Systems Science Computational Centre at the University of Queensland and colleagues have been investigating a type of repetitive earthquake that typically occurs before volcanic eruptions.
+"Quite often these long-period earthquakes are observed before a volcano does something nasty," says Hales.
+"It's basically an indication that something's going to happen, but no-one has actually worked out how they occur."
+Recently, scientists have begun to think the quakes may be caused by areas of instability in volcanic lava called shear bands. But until now there has been no accurate way to explain the connection.
+"It's been eluding us exactly what the volcano is trying to tell us with these signals," Hale says.
+"People have had a go at trying to correlate shear bands with these earthquakes, but so far it hasn't been convincing."
+At the Australian Institute of Physics conference in Brisbane today, Hale described how her new model incorporates processes such as the formation of crystals in lava to make the correlation more precise.
+"It was a case of putting two and two together to pinpoint how these signals are being generated," she says.
+When Hale used real-world data from Soufri&egrave;re Hills Volcano, which devastated the island of Montserrat, her model confirmed that shear bands were being generated at the depths where long-period earthquakes occur.
+More research needs to be done to further refine scientists' understanding of the processes behind long-period earthquakes, Hale says, but the new model could be an important development.
+"We're now getting closer to understanding where and why these signals occur," she says.
+"Basically it could potentially give us the ability to predict eruptions."
+
+Neanderthal foot bones in a block of cemented sand and clay from the El Sidrón cave in Spain
+Neanderthals had different ethnic groups, often starved and probably practised cannibalism.
+That's the news from a recent study of the skeletal remains from eight Neanderthals who lived 43,000 years ago in northwest Spain.
+The findings, published online in the Proceedings of the National Academy of Sciences, raise questions about Neanderthal lifestyle.
+Why, for instance, would they have resorted to cannibalism? What harsh conditions caused the wear and tear evident on surviving bones?
+There are two possible reasons why Neanderthals would have dined on their dead, according to lead author Dr Antonio Rosas, a scientist in the palaeobiology department at the National Museum of Natural Sciences in Madrid.
+"One is that they needed to eat whatever was at hand, including human flesh, because ecological conditions for their survivorship, such as extreme cold weather and no meat from hunting, were really hard," Rosas says.
+The other possibility, he says, is that "this was done in the context of something we may think of as symbolic".
+Rosas suggests the virtual absence of animal remains at the site, a cave called El Sidr&oacute;n, may point either to ritual killings or unsuccessful hunting. Neanderthals are thought to have subsisted primarily on meat.
+Toothy clues
+The Neanderthals studied ranged in age from infancy to young adulthood. Their teeth revealed that tooth growth often stopped abruptly due to illness or malnutrition. 
+Adolescence in general appears to have been a particularly hard time, possibly due to separation from parents and the resulting need for self-sufficiency.
+Cut marks associated with butchery were found on some of the remains, particularly those of the younger individuals.
+The skeletal remains also reveal that these Neanderthals possess a different bone structure than individuals found elsewhere in Europe.
+It appears that Neanderthals fell into at least two basic ethnic groups that coincided with their north-south geographical distribution.
+Southern Neanderthals from the Iberian Peninsula, the Balkans, the Middle East and Italy had broader and shorter faces than northern Neanderthals from populations living north of the Pyrenees, the Alps, portions of Asia and central and eastern Europe, the researchers say.
+Scientists are now debating whether interbreeding with modern humans occurred and why all of these Neanderthal groups appear to have gone extinct.
+"It does look, from a variety of data, that Neanderthals were subject to episodes of extreme scarcity, with which their cultural and social systems sometimes couldn't cope," says Professor Steven Kuhn, an anthropologist at the University of Arizona.
+"There could also be a link between boom-and-bust subsistence and occasional cannibalism."
+Sharing out the chores
+Kuhn and colleague Professor Mary Stiner theorise that modern humans better divided labour along the lines of gender and age.
+Instead of everyone working toward the next big kill, women and children in early modern human groups devised other food-obtaining strategies, such as gathering fruits and nuts.
+Such diversification underlies our success, even today, they say.
+"It is clear that the kinds of cooperative, diversified economies practised by recent hunter gatherers are 'underwritten by' our sophisticated cognitive and communicative abilities," says Kuhn.
+"That's what allows people to negotiate and maintain their complex patterns of dependency and cooperation, keep each other in line, etc. But whether the cognitive development is cause or consequence isn't clear to us."
+
+Transparent module of skinny sliver cells, which provide a greater surface area to capture sunlight
+The cost of producing solar panels could be sliced by more than 60% thanks to technology being developed by Australian researchers, physicists heard today.
+Professor Andrew Blakers, director of the Centre for Sustainable Energy Systems at the Australian National University, says 'sliver technology' could reduce the price of solar power to below the current retail price of electricity.
+And he says this could make it cost-effective for householders to buy solar panels rather than electricity from the grid.
+Blakers describes the latest refinements in the technology at the Australian Institute of Physics conference in Brisbane.
+The system works by taking a standard solar cell about 1 millimetre thick and cutting it into tiny slices that are just 120 micrometres wide.
+"Imagine a standard solar cell is a loaf of bread. When you put it out in the sun it generates energy based on its surface area," Blakers says.
+"Now imagine you cut that loaf up into slices and lay them horizontally. You get a lot more surface area."
+This technique allows researchers to use much smaller amounts of expensive silicon to generate the same amount of electricity.
+This can also keep manufacturing costs down, as all the processing steps normally carried out on solar cells are done while the slices are still in the 'loaf'.
+"We're looking at major reductions in the total cost without the need for major scientific breakthroughs," Blakers says.
+"It's about doing a good engineering job using known scientific principles, in contrast to some other technologies."
+The sliver technology is also efficient at converting sunlight to electricity, he says.
+In recent months, the researchers have achieved efficiencies over 20%, making it the world's most efficient commercial thin-film solar cell.
+But further developments would be needed, such as figuring out how to cut thinner slivers, he says.
+Blakers invented the technology with colleague Dr Klaus Weber and developed it with funding from energy supplier Origin Energy and the Australian Research Council.
+Blakers and Weber won the Australian Institute of Physics' Walsh Medal for their work.
+
+Would you use car tyres made using nanotechnology?
+The public has a neutral attitude towards the risk of nanotechnology and will accept some risk from specific products if their benefits are high, a new US survey has found.
+The first large-scale survey of its kind is published in the current issue of the journal Nature Nanotechnology.
+"Our results showed that nanotechnology was seen as relatively neutral," say Professor Steven Currall of University College London and colleagues.
+The survey found people perceived nanotechnology as less risky and more beneficial than a number of other technologies such as genetically modified organisms, pesticides, chemical disinfectants and human genetic engineering. 
+But they saw it as less beneficial than solar power, vaccinations, hydroelectric power and computer display screens.
+The researchers also studied people's acceptance of four hypothetical nanotechnology applications - a drug, a skin lotion, car tyres and refrigerator gas coolant.
+The researchers defined the environmental and health risks of each application and they found that people judged risks and benefits as a package.
+"When the benefits are low, consumers are more concerned about risks than when benefits are high," they say.
+The researchers say if the public is to have a measured and informed response to nanotechnology in the future, they need easy access to information on risks and benefits.
+"Now is the time to educate the public aggressively with facts about the risks and benefits of nanotechnology," they say.
+But Australian researcher, Dr Stephen Healy of the School of History and Philosophy of Science at the University of New South Wales, says most people don't just trade-off risks and benefits to decide whether to accept a technology.
+People's trust in decision-makers also play an important role, says Healy, whose research interests include risk and public involvement in decision-making on new technologies.
+He also says the researchers mistakenly suggest risks are a property of technologies themselves in isolation.
+But whether or not nanoparticles present a risk, for example, will be partly determined by what people do with them, says Healy.
+"It's not simply a matter of public perception and it's not simply a matter of the way they're made, it's a matter of the way they're used," he says.
+Healy is not surprised the survey found the public has a neutral view on nanotechnology.
+"Nanotechnology is very much an emergent technology and the existing commercial applications are very low profile to say the least," he says.
+Professor Jim Falk of the Australian Centre for Science, Innovation and Society at the University of Melbourne, says the survey findings call for genuine public engagement on new technologies like nanotechnology.
+"We have no national capacity in Australia for engaging the public in those issues except through the media and commissions of inquiry," he says.
+Over 5500 people were involved in the web and telephone survey, which was funded by the US National Science Foundation and Rice University in Texas.
+
+This gully deposit, which scientists say is evidence of water on Mars, formed sometime between August 1999 and February 2004. So does this mean that water is still flowing today?
+Photographs of Mars show features that most likely were made by water flowing on the planet today, says the US space agency.
+"No one expected what we found today," says Dr Kenneth Edgett, a scientist with Malin Space Science Systems in San Diego. "We are talking about liquid water that is present on Mars right now."
+The images were taken by NASA's Mars Global Surveyor, which had been studying the Red Planet for a decade before an apparent mission-ending failure last month.
+The discovery raises the prospect that life could exist on Mars today, says Dr Michael Meyer, lead scientist for NASA's Mars Exploration Program.
+The agency has mounted a series of increasingly sophisticated missions to look for signs of past water on Mars in hopes of identifying areas that could have been suitable for life to form.
+"Maybe we no longer have to think about following the water, but watching the water," Edgett says.
+The conclusion that water flows on Mars today is based on photographs the Global Surveyor took of gullies etched in the Martian soil.
+Two sites in particular caught researchers' eyes because there were noticeable changes between pictures taken six years ago and ones snapped in 2004 and 2005.
+Both show the gullies had filled with a light-coloured deposit, which is believed to be frozen water.
+Scientists believe the water emanated from deep within the planet and gradually welled up toward the surface. Once it encountered the frigid Martian air, however, it froze, forming an ice dam.
+Water continued to build up underground until there was enough pressure to burst the ice cap and allow a jet of water to flow down the channels.
+The amount of water is about what would be needed to fill five to 10 swimming pools, Edgett says.
+The findings will be followed up by a new higher-resolution camera aboard NASA's Mars Reconnaissance Orbiter, which began its mission last month.
+The Global Surveyor team also found new impact craters, raising the prospect that meteorite hits are a concern as NASA begins to think about sending human explorers to Mars.
+
+Big brown bats, like this one, navigate over long distances using the Earth's magnetic field as a guide
+Scientists believe a species of bat has an in-built magnetic compass to find its way home over long distances, in addition to its famous echolocation, which guides it around its neighbourhood. 
+Princeton University batologists publish their findings today in the journal Nature.
+The researchers used radio telemetry aboard a small aircraft to track big brown bats (Eptesicus fuscus) that were released 20 kilometres north of their home.
+They first tested a control group of bats, which headed due south towards the roost without a problem. 
+Two other groups of bats were then exposed to a false magnetic field for 90 minutes, 45 minutes before and 45 minutes after sunset. 
+One field was 90&deg; clockwise and the other was 90&deg; anticlockwise from magnetic north.
+The point of this was to see whether the bats used Earth's magnetic field as a guide and, if so, to see whether the bats used sunset or the stars as an additional cue. 
+The 'clockwise' group of bats flew due east, while the 'anticlockwise' group went due west, suggesting that they had been using a magnetic compass that may have been calibrated by the sunset. 
+But some of the bats corrected their course and arrived home safely, which implies that, like homing pigeons, they can make a fix if a navigational glitch occurs.
+World's longest bat tongue?
+Meanwhile, another study, also published by Nature, sheds light on a remarkable bat species whose tongues are one and half times longer than their bodies. 
+The nectar bat (Anoura fistulata) lives in the cloud forests of the Ecuadorean Andes, feeding on flowers whose nectar is hidden at the end of long funnels.
+Nathan Muchhala, of the University of Miami, suggests the extreme length of the bat's tongue coevolved with the long flowers of the plant.
+
+A message sent using entangled, or spooky, particles of light has been beamed across the ocean
+Scientists have used quantum physics to zap an encrypted message more than 140 kilometres between two Spanish islands.
+Professor Anton Zeilinger from the University of Vienna and an international team of scientists used 'spooky' pulses of light to send the message.
+They say this is an important step towards making international communications more secure.
+Zeilinger described the study this week at the Australian Institute of Physics meeting in Brisbane.
+The photons they sent were linked together through a process known as quantum entanglement.
+This means that their properties remained tightly entwined or entangled, even when separated by large distances, a property Einstein called spooky.
+The group's achievement is important for the emerging field of quantum cryptography, which aims to use properties such as entanglement to send encrypted messages.
+Research groups around the world are working in this field. But until now they have only been able to send messages relatively short distances, limiting their usefulness.
+Zeilinger's team wants to be able to beam the messages to satellites in space, so they could theoretically be relayed anywhere on the planet.
+To test their system, the team went to Tenerife in the Canary Islands, where the European Space Agency operates a telescope specifically designed to communicate with satellites.
+Instead of pointing the telescope at the stars, Zeilinger says, the scientists turned it to the horizontal and aimed it towards a photon sending station 144 kilometres away on the neighbouring island of La Palma.
+"Very broadly speaking, we were able to establish a quantum communication connection," he says.
+"We worried a lot about whether atmospheric turbulence would destroy the quantum states. But it turned out to work much better than we feared."
+The results suggest it should be possible to send encrypted photons to a satellite orbiting 300 or 400 kilometres above the Earth, he says.
+"This is our hope. We believe that such a system is feasible."
+The next step is to try the system out with an actual satellite, a project which is likely to involve the European Space Agency and others.
+"This is about developing quantum communications on a grand scale,"
+Zeilinger says.
+His team expects to publish its results soon.
+
+Embryonic stem cells could be grown into islet cells to treat diabetes, say researchers
+Australian stem cell researchers will start negotiating with IVF clinics to access human eggs following this week's landmark decision to overturn a ban on creating cloned embryos specifically for scientific research.
+Despite objections from Prime Minister John Howard and the new leader of the opposition, Kevin Rudd, the lower house of the Australian parliament last night voted to allow the process.
+This paves the way for laws to implement the recommendations of the Lockhart review into stem cell research.
+"I think it's fantastic news. It's raised the morale of the scientists," says Professor Alan Trounson, international director of the Australian Stem Cell Centre. "We're thrilled."
+His team wants to use somatic cell nuclear transfer (SCNT) to investigate options for disease diagnosis and treatment once the new laws are enacted.
+SCNT involves the creation of an embryo by inserting a nucleus from a patient's body cell into an egg cell that has had its nucleus removed.
+Under the new laws such an embryo would be permitted to grow for 14 days and provide scientists with stem cells for use in research.
+But the first step for researchers like Trounson is to get hold of a ready supply of human eggs and he's not sure whether there will be enough.
+"We're looking forward to seeing whether we can obtain eggs for these studies. That will be the critical component I think," he says.
+"We'll be talking to our colleagues in the infertility clinics because they will be the connection to obtaining human eggs for making embryonic stem cells."
+Eggs a limiting factor
+Neuroscientist Professor Peter Schofield of the Lockhart review agrees that finding eggs will be a key issue.
+"In practice we will probably find that eggs may be a limiting factor," he says.
+
+Gorillas' social habits make it easy for the Ebola virus to spread among and between groups, researchers say
+The Ebola virus may have killed more than 5000 gorillas in West Africa, enough to send them into extinction if people continue to hunt them too, researchers say.
+The virus is spreading from one group of the already endangered animals to another, the international team of experts report today in the journal Science. 
+And it appears to be spreading faster than it is among humans. 
+"The Zaire strain of Ebola virus killed about 5000 gorillas in our study area alone," write primatologist Dr Magdalena Bermejo of the University of Barcelona in Spain and colleagues.
+Ebola haemorrhagic fever is one of the most virulent viruses ever seen, killing 50-90% of victims.
+The World Health Organization says that it killed 1200 people infected between its discovery in 1976 and 2004.
+The virus is transmitted by direct contact with blood, organs or other bodily fluids. There is no cure or good treatment, although several groups are working on vaccines. 
+Several experts have noted that chimpanzees and gorillas are also killed by the virus, and suspect that people may have caught it from infected apes, perhaps when hunting them. 
+But it is not clear whether the gorillas are infecting one another, or being repeatedly infected and reinfected by another species of animal, perhaps a bat. 
+Bermejo's team has been studying a group of western gorillas in the Lossi Sanctuary in northwest Republic of Congo.
+"By 2002 we had identified 10 social groups with 143 individuals," they write. 
+Quick deaths
+In 2001 and 2002, several outbreaks of Ebola had begun killing people along the Gabon-Congo border.
+By October 2002, the researchers had found 32 dead gorillas, and of the 12 they tested for Ebola, nine were positive. 
+"[Bermejo] knew these animals individually, and in the course of three months they all died," says Dr Peter Walsh, an ecologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who worked on the study. 
+Eventually the researchers counted 221 dead gorillas. Based on what they and other experts knew, Walsh extrapolated what the total impact must be to come up with the estimate of 5500 gorillas killed by Ebola in that area. 
+He says no one knows precisely how many gorillas are in the world and how many have died.
+"But I know what's the typical mortality rate in those areas that are affected. It's an educated guess. A quarter of the gorillas in the world have died from Ebola in the last 12 years. It's huge," Walsh says. 
+"Add commercial hunting to the mix, and we have a recipe for rapid ecological extinction," the researchers write. 
+Their report supports a study published in July that showed gorillas were spreading the virus within their social groups. 
+"Our work is complementary to that; we have shown it is spreading between groups," Walsh says. 
+Walsh says gorilla groups share territories, often eating fruit from the same tree, although at different times. Faeces from a sick gorilla could easily infect other gorillas. 
+Gorillas and chimpanzees also touch and handle the bodies of other apes when they find them, something known to transmit Ebola between humans. 
+"The issue here is that there is a certain amount of work that needs to be done to take these vaccines that already exist and put them into gorillas," Walsh says.
+
+Africa is suffering from a double blow: malaria and HIV. Now scientists say that one could exacerbate the other
+Malaria may be helping to spread HIV across Africa, the continent hardest hit by AIDS, scientists say. 
+The way the two diseases interact greatly expands the prevalence of both among people in sub-Saharan Africa, a team of scientists say today in the journal Science.
+Malaria, a mosquito-borne disease caused by a parasite, greatly boosts viral load, the amount of HIV in the blood of infected people, they say.
+This makes them more likely to infect a sexual partner with HIV.
+"Higher viral load causes more HIV transmission, and malaria causes high HIV viral load," says lead study author Dr Laith Abu-Raddad of the Fred Hutchinson Cancer Research Center in Seattle and the University of Washington. 
+Abu-Raddad, an AIDS researcher, estimates that malaria has helped HIV infect hundreds of thousands and perhaps millions of people in sub-Saharan Africa.
+At the same time, HIV fuels malaria's spread because HIV-infected people are more susceptible to malaria as a result of HIV ravaging the immune system, the body's natural defences, the researchers say. 
+AIDS and malaria are concentrated in sub-Saharan Africa. And Abu-Raddad says scientists were puzzled when they realised that the risky sexual behaviour by people in the region was not by itself sufficient to explain the swift spread of HIV, so other factors must be involved. 
+They focused their work on Kisumu, a Kenyan city by Lake Victoria where HIV and malaria are both common.
+They say 5% of HIV infections can be blamed on the increased HIV viral load due to malaria, and 10% of adult malaria cases can be blamed on HIV. 
+Since 1980, 8500 more people became HIV positive, and there were 980,000 more episodes of malaria (a person can get it more than once) in a city whose adult population is 200,000, the study found.
+Public health efforts
+The findings have implications for public health efforts, Abu-Raddad says, showing the importance for authorities to tackle these diseases together. 
+Of the 39.5 million people worldwide infected with HIV, 24.7 million are in the poor countries of sub-Saharan Africa. About 2.1 million of the world's 2.9 million AIDS deaths in the past year were also in this region.
+Malaria kills more than a million people annually, mostly young children in sub-Saharan Africa. 
+The researchers produced their results with a mathematical model using HIV and malaria infection data gathered in Malawi by Dr James Kublin of the Hutchinson Center.
+This enabled them to quantify for the first time the synergy between malaria on HIV and its toll on people. 
+Scientists previously determined that a lack of male circumcision and the incidence of genital herpes also were facilitating the spread of HIV.
+Abu-Raddad notes that circumcised men are much less likely to get HIV, and that genital herpes opens a door for HIV to infect a person. 
+Abu-Raddad says malaria now can be considered a third serious factor facilitating the spread of HIV. 
+The two diseases drive one another even though they have different modes of transmission - malaria by mosquito and HIV predominantly by sexual intercourse - Abu-Raddad notes. 
+He says once a person with HIV gets malaria, his or her viral load goes up and stays higher for six to eight weeks, making the person far more infectious to others.
+
+Just because you know someone well doesn't mean you can choose the right present, new research shows
+If you really want an mp3 player this Christmas, but your beloved buys you a radio, don't be too disappointed.
+New international research suggests knowing someone very well actually makes predicting his or her tastes more difficult.
+The study, published in the December issue of the Journal of Consumer Research, goes some way to explaining why people often miss the mark and end up buying weird, inappropriate, or just plain bad gifts for the ones they love most.
+Researchers from the Netherlands and Belgium invited 35 couples who had been in a relationship for at least six months to predict their partners' taste in furniture.
+All 70 participants were first asked to choose their own favourite bedroom suites from 30 on offer.
+Half were then asked to predict their partner's favourites while the other half were asked to predict the favourites of a stranger, person X, who in reality was their partner.
+The researchers conclude that knowing a lot about your partner can actually get in the way of choosing the perfect gift.
+Not only do people become overconfident that they know what their partner will like, but their tendency to assume their tastes are very similar mean they often miss the cue that they're getting it wrong.
+"Our results suggest that familiarity causes [people] to put an overly heavy weight on pre-stored information," write the authors. 
+"The pre-stored information that people possess about their partner is extensive. This elaborate knowledge makes predictors overly confident, such that they do not even attend to product-specific attitude feedback." 
+Australian professor of psychology at the University of New South Wales, Joseph Forgas, says it's hardly surprising that people get it wrong when buying presents for others, as they often get it wrong when buying things for themselves.
+The possible reason? Affluence.
+"People already pretty much have everything that has real utility value for them, so most discretionary purchases are to buy items we don't really need, ie goods that have only symbolic, identity value and only minimal utility value," he says.
+"Such purchases are mainly to make statements about ourselves. And people are not very good in figuring out what statement to make, and what to make it with.
+"For example, some people may think that buying a red Ferrari signals power and wealth, while to others it may just signal sexual inadequacy and impotence."
+
+Could automated answers to your IT questions help reduce frustration when things go wrong?
+The next time you email the IT help desk, you may find yourself dealing with a computer, not a human.
+If a new system that Australian researchers are developing takes off, 'intelligent' computers will generate their own answers to your queries.
+The research by computer scientists Dr Yuval Marom and Professor Ingrid Zukerman of Monash University in Melbourne will be presented at the International Joint Conference on Artificial Intelligence in Hyderabad, India next month.
+"Help desk operators are generally dealing with the same thing over and over again," says Marom.
+And he says many emails can be answered by mixing and matching parts of generic responses, which the researchers' software will generate.
+It can also help automate answers that require a more personalised response, says Marom.
+The software was developed by analysing patterns between a set of 30,000 genuine pairs of questions and answers from an email help desk and generalising relationships between them.
+The emails came from the large international computer hardware company involved in the Australian Research Council Linkage grant that funded the research.
+The software defines several categories of questions that can be answered by generic responses, such as standard advice on how to arrange for a computer to be repaired.
+Then there are questions that require more specific answers. 
+These involve the system directly matching the words in the question to answers in the database, using similar technology to Google.
+But unlike Google, the customer can enter in a much longer query, describing the problem in detail and what they have already done to try and solve it.
+Speed and accuracy
+Marom says the benefit of automated responses is that they can be obtained at "Google speed" instead of having to wait longer for a human to get around to typing a response.
+But how accurate are the answers?
+Marom says the system can be set so that it only fires off an automated answer when it has a certain level of confidence the answer is accurate.
+But customers will tolerate some inaccuracy or incomplete answers as long as they are sufficiently knowledgeable, he says.
+For example, if the system gives the customer the right webpage for downloading some software but tells them the wrong procedure, the customer might still find the automated answer useful.
+And if they get fed up they can always opt out and contact a human instead with the click a button, says Marom.
+So far ratings by staff in Marom's department suggest the automated answers are pretty good when compared to the answers humans give.
+But he says the next step is to evaluate the system online with a real-life email help desk.
+Accuracy and jobs
+Marom says that automated help desk software will cost jobs. But he says some humans will always be required to answer questions the system is not confident of answering.
+Exactly how many humans will depend on where the confidence levels are set as it's a trade-off. 
+If the confidence level is set too high, the system requires more humans to answer the harder questions. 
+If the confidence level is set too low, it could risk annoying customers.
+Marom says the system could be applied in many areas from tax queries to health queries.
+Although of course, he says, the level of confidence for answering health queries would have to be pretty high.
+
+Fossils found on New Zealand's South Island belong to an ancient mammal lineage
+Palaeontologists have found remains of one of the most primitive type of land mammal in the world, a mouse-sized creature that's unlike any mammal alive today.
+The find, at the edge of a swampy lake on New Zealand's South Island, not only fills a gap of the nation's fossil record, it may also help us understand more about the origin of mammals worldwide.
+Researchers, led by Trevor Worthy from Australia's University of Adelaide, publish their results today online in the Proceedings of the National Academy of Sciences.
+Many types of mammals evolved in the Mesozoic period when the dinosaurs dominated, says co-author Alan Tennyson, a palaeontologist from the Museum of New Zealand Te Papa Tongarewa.
+But most of those early lineages are now extinct and mammals living today fall into only one of three groups: placentals, marsupials or monotremes.
+But this latest find, in sediments deposited 16-19 million years ago, doesn't fit into any of these groups.
+"This is an incredible find. We never expected to find anything like this," says Tennyson.
+"What's so exciting about this fossil mammal is that it is from one of those ancient lineages that we thought had become extinct much earlier. This will help us understand more about the origin of mammals worldwide," he says.
+The find is particularly significant for New Zealand as there are virtually no fossils of terrestrial vertebrates between 65 million years ago, when an asteroid impact is thought to have wiped out the dinosaurs, and about 1 million years ago.
+In other parts of the world many different mammals evolved to replace dinosaurs as the dominant species.
+But in New Zealand the only terrestrial vertebrates that seemed to have evolved were reptiles, frogs, and birds - not mammals.
+That's despite the fact that New Zealand's landmass separated from Gondwana after many mammals had evolved.
+"The suggestion has been that giant birds, like the extinct Haast eagle and the moa, filled the ecological niches that mammals like tigers and grazing animals did elsewhere," says Tennyson.
+"But this is a very primitive mammal and it's unlikely to have lived here for 60 million years without diversification. So it opens the possibility that there may be bigger mammals to be found."
+The researchers say the discovery implies the existence of one or more 'ghost lineages' and suggests that mammals may have existed on New Zealand more than 125 million years ago.
+That may contradict an alternative theory for the lack of fossil evidence for terrestrial mammals: that New Zealand was completely submerged about 25 million years ago and that all of its animals and plants arrived from nearby landmasses. 
+But the paper suggests that the discovery, along with other Mesozoic survivors such as the lizard-like tuatara and New Zealand's primitive frogs, confirms that at least some land remained above water throughout the period.
+
+A colonial siphonophore, which grows to 1.5 centimetres, found off the coast of Broome in northwestern Australia
+A Jurassic 'shrimp' thought extinct 50 million years ago has been found in Australian waters, a census of marine life shows.
+Neoglyphea neocaledonica, found on an underwater peak in the Coral Sea, is the oldest marine organism listed in the 2006 Census of Marine Life, a global effort involving 70 nations.
+The census, which is due for completion in 2010, also found marine creatures thriving by a record hot volcanic vent in the Atlantic and in dark waters under thick Antarctic ice.
+Researchers also found 150 new types of fish among 500 new marine species, including furry crabs and a lobster off Madagascar.
+Many species were found in places long thought too hostile for life including by a vent spewing liquids at 407&deg;C and other habitats that are dark, cold or deep.
+Some places seem as inhospitable as planets such as Mars or Venus, the researchers say. 
+"The age of discovery is not over," says Jesse Ausubel, a program manager at the US Sloan Foundation, a sponsor of the 10-year census.
+Among discoveries in 2006 are shrimps, clams and bacteria living by the searing 407&deg;C vent on the floor of the Atlantic Ocean north of Ascension Island, the hottest sea vent ever documented and more than hot enough to melt lead.
+"This is the most extreme environment and there is plenty of life around it," says Professsor Chris German, of the UK's National Oceanography Centre and a leader of the Atlantic survey.
+He says one big puzzle is how creatures cope with shifts in temperatures. For instance, water on the seabed at 3000 metres is just 2&deg;C yet many creatures withstand near-boiling temperatures of up to 80&deg;C from the thermal vent.
+German says it is a bit like a person agreeing to live in a blistering sauna and be hosed at random with freezing water. 
+Scientists have not yet probed how hardy the microbes nearest the hottest part of the vent are.
+Another expedition found crustaceans, jellyfish and single-celled creatures living in darkness in the Weddell Sea off Antarctica under ice 700 metres thick and 200 kilometres from open water. Most of those creatures are new to science. 
+"You can think of it as a cave, one of the remotest caves on Earth," Ausubel says of findings by a robot camera. 
+"Wherever we've gone on Earth we've continued to find life," German says, adding that recent discoveries could be encouraging for the search for life elsewhere in the universe.
+The biggest new species in the census is probably a 1.8 kilomgram rock lobster found off Madagascar. A furry crab, dubbed a 'Yeti crab', was also found off Easter Island.
+In the longest migration ever documented, census researchers tracked sooty shearwater birds on a 70,000 kilometre flight sweeping round the Pacific in 200 days, an average 350 kilometres a day.
+
+Ten studies published since 1999 have identified the human papillomavirus in breast tumours. But more studies are needed to show how closely the two are linked
+Breast cancer could be sexually transmitted, says a researcher who has found the same virus that causes cervical cancer in breast cancer tumours from Australian women.
+Emeritus Professor James Lawson of the University of New South Wales and colleagues have found the same form of the human papillomavirus (HPV) associated with cervical cancer in almost half the breast tumour samples they tested.
+It's the first study of its kind in Australia, although international studies have also found cervical cancer-related HPV in breast cancer cells.
+He says while the evidence is far from conclusive, "it's possible and totally worthy of investigation" to suspect that HPV could also cause breast cancer.
+Lawson says it's possible that HPV is spread by sexual activity or during showers or baths, when the virus could be transferred from the genital area to the breasts via the nipple ducts.
+"We know that the virus explodes out of the cell and is spread by touch, so it's fairly obvious that it could be spread by sexual activity to the breast, you could also argue that it would be spread by washing and bathing," he says.
+Lawson says more research is needed to establish whether HPV is actually causing the breast cancer or if women with breast cancer are more prone to infection with the virus.
+Younger women
+Lawson and colleagues last year published the results of a DNA analysis which found 24 out of 50 breast cancer samples also tested positive to HPV 18, the same form of the virus implicated in breast cancer.
+A subsequent review, published in the journal Future Microbiology in June this year, found various forms of high-risk HPV had been identified in 10 separate breast cancer studies since 1999.
+In a letter published online in the British Journal of Cancer last month Lawson reports that a review of the 2005 study found women with HPV positive breast cancers were on average about eight years younger than those whose tumours did not test positive to the virus.
+He says this lends weight to the sexual transmission theory, because HPV is more common in younger women who are more likely than older women to have had multiple sexual partners, something he describes as a "post-pill phenomenon".
+Lawson says it isn't the first time a virus has been associated with breast cancer. 
+The mouse mammary tumour virus, which causes breast cancer in mice, has been known about since the 1930s, and in a 2004 study Lawson reported finding a genetically similar version of the virus in Australian women.
+Lawson says if it's true that HPV can cause breast cancer as well cervical cancer, the introduction of the cervical cancer vaccine, developed by Australian of the Year Professor Ian Frazer, should also cut rates of breast cancer.
+He says he is currently pushing for a study into this.
+"The real proof of all this will be the vaccine, but you'll have to wait [a long time] for [the results]," he says.
+"It makes sense to follow that group of girls, and when some of them get breast cancer, to see if any of them are HPV positive breast cancers.
+"Theoretically the answer should be no."
+Doubts
+But chief executive officer of Cancer Council Australia, Professor Ian Olver, says while it's possible that a virus could cause breast cancer the existing studies are small and inconclusive.
+"What we've got is small studies that have found an association between HPV and breast cancer ... but they haven't shown anything that could say it's causal," he says.
+"I think you need much bigger studies and a mechanism by which HPV was implicated in the development."
+A recent article published online ahead of appearing in the journal The Breast failed to find evidence of HPV in a study of 81 Swiss women.
+"Our analysis could not support a role of HPV in breast carcinoma," the study concludes.
+
+New research shows that the outermost layer of the atmosphere will lose 3% of its density over the coming decade, a sign of the far-reaching impacts of greenhouse gas emissions. As the density declines, orbiting satellites and space junk will experience less drag
+Human increases in carbon dioxide emissions are thinning the Earth's outer atmosphere, making it easier to keep the space station aloft but prolonging the life of dangerous space junk, scientists say. 
+"It's a bit of a two-edge sword," says Stanley Solomon, a US scientist at the National Center for Atmospheric Research in Boulder, Colorado.
+"In the future, it will be a little bit easier to keep the space station, for instance, in orbit. It will need a little bit less fuel," he says.
+"On the other hand, it will give space junk a much longer lifetime," he told a meeting of the American Geophysical Union in San Francisco. 
+Solomon is the co-author of a study presented this week that found the burning of fossil fuels and increase of carbon dioxide emissions will make the Earth's outer atmosphere above 100 kilometres 3% less dense by 2017.
+The study, which is also published in the journal Geophysical Research Letters, found a decrease in density of about 5% between 1970 and 2000. 
+Although scientists say that carbon dioxide contributes to global warming closer to Earth's surface, in the thinner outer atmosphere where spacecraft orbit, a cooling effect takes place. Solar activity also affects the outer atmosphere. 
+As this outermost region becomes less dense, it produces less drag on satellites, spacecraft and tens of thousands of pieces of discarded space debris from previous missions orbiting at about 400 kilometres from Earth's surface.
+"These objects are now experiencing less drag proportionally than they did 30 years ago," Solomon says. 
+A steady stream of space launches since Sputnik's in 1957 has left about 10,000 orbiting objects bigger than the size of a grapefruit, and 100,000 larger than a centimetre, says Dr Kent Tobiska, president and chief scientist of Space Environment Technologies in Pacific Palisades, California. 
+The International Space Station now in orbit must readjust its path several times a year to avoid colliding with such debris; a chance hit with a spacewalking astronaut could prove fatal.
+
+A researcher has suggested that the origin of Aboriginal language can be traced back to a time when Australia and New Guinea were one
+Aboriginal languages may be much older than people think, argues a linguistic anthropologist who says they originated as far back as the end of the last ice age around 13,000 years ago.
+This challenges existing thinking, which suggests Aboriginal languages developed from a proto-language that spread through Australia 5000 to 6000 years ago.
+The key to the new hypothesis is prehistoric Australia's single land mass 13,000 to 28,000 years ago, when New Guinea and Tasmania were still attached, says Dr Mark Clendon in the journal Current Anthropology.
+Clendon says the continent, known as Sahul, was relatively densely populated on the land bridge connecting northern Australia to New Guinea, now separated by the Arafura Sea.
+The other populated area was along what is now Australia's eastern seaboard.
+The two population groups were separated by a vast, cold, windswept, arid stretch of land that covered most of the continent, says Clendon, who was with the Batchelor Institute of Indigenous Tertiary Education when he published the research.
+The eastern group spoke a tongue that became what is known today as Pama Nyungan and includes languages like Pitjantjatjara, Yolngu and Warlpiri.
+And the Arafurans spoke another family of languages used in northern Australia today.
+"What I'm suggesting is that Pama Nyungan and non-Pama Nyungan languages go back about 13,000 years to when there was a land bridge between New Guinea and Australia," he says.
+Until now, the reason why these two Aboriginal language groups are so different, each with a distinct grammar and vocabulary, has been a mystery.
+Climate change
+Around 11,000 years ago what was the Arafura plain was flooded by rising seas as the ice age ended.
+This caused the northern people to migrate into either New Guinea or to northern parts of Australia.
+Meanwhile, increased rainfall and warmer temperatures made inland parts of the continent more habitable and sparked a westward migration of eastern dwellers.
+This introduced their language group to more central areas of Australia.
+Both groups maintained their distinct languages, Clendon says. 
+His hypothesis provides an alternative picture to the traditional view that 6000 years ago a single proto-language spread from the Gulf of Carpentaria around Australia, eventually giving rise to existing Aboriginal languages.
+"We know about changes in climate and sea levels at the end of the Pleistocene era," Clendon says.
+"I'm suggesting the way languages are configured in Australia today are a result of those changes that happened at the end of the ice age."
+Provocative but unconvincing
+Writing in a reply to Clendon's article, Professor Nicholas Evans, an expert in Aboriginal languages from the University of Melbourne, describes Clendon's hypothesis as "fresh and provocative".
+However, he says there are flaws in the argument, including that there is only weak evidence of similarities between southern New Guinea and northern Aboriginal languages.
+Evans says he remains to be convinced about Clendon's proposal.
+"[But] it adds a welcome alternative to a field in which we are still a long way from having any clear picture of the unimaginably long human occupation of Sahul," he says.
+
+Air pollution in Asia is increasing rainfall in parts of Australia. But scientists are concerned that could be reversed when the pollution is cleared up, therefore plunging more of Australia into drought
+More of Australia could become affected by drought if its nearest neighbours start reducing air pollution, a study suggests.
+Dr Leon Rotstayn of CSIRO Marine and Atmospheric Research says a new computer climate model shows aerosol pollution in Asia is having a long-distance effect on weather in Australia.
+He says the modelling shows that the airborne haze made up of tiny particles from industrial and domestic pollution is cooling the land and oceans around Asia.
+The haze isn't travelling to Australia. But it's been changing the balance of wind and temperature between Asia and Australia, causing heavier rainfalls in central and northwest parts of Australia.
+"What has been observed in the last 50 years is that it has been getting drier in the south and east of Australia and wetter in the northwest and centre," he says.
+"Our pilot modelling results suggest that the Asian haze may be driving that trend towards more rain." 
+Getting rid of the haze could reverse that pattern, he says.
+The research, which will be published in the  Journal of Geophysical Research early next year, is the first time researchers have tried to demonstrate the effect of aerosols on Australia's climate.
+Particles
+The pollution factored into the CSIRO model includes industrial and domestic emissions of particles such as black carbon, from burning diesel, and sulfide particles from coal.
+Rotstayn says this aerosol pollution has a cooling effect because it forms a blanket that keeps the Sun's radiation from reaching the surface of the Earth.
+The particles also cause thicker and more persistent clouds, which reflect heat back into space.
+"The cooling effect of aerosols is a combination of the direct effect of stopping sunlight getting through and the indirect effect whereby the aerosols make clouds more effective," he says.
+"The aerosol haze is cooling Asia and the oceans around [it] and that's affecting the monsoonal winds which bring the summer-time rainfall to the northern parts of Australia."
+He says the trend could be reversed, with serious implications for Australia, if Asian emissions are reduced.
+"Sooner or later those emissions will be cleaned up and a trend of increasing rainfall in the northwest and centre could be reversed," he says.
+"This is potentially serious, because the northwest and centre are the only parts of Australia where rainfall has been increasing."
+Not just a greenhouse problem
+The study shows that we shouldn't underestimate the impact of aerosols on Australia's climate, Rotstayn says.
+"We don't really have much aerosol pollution in Australia most of the time so there's been an assumption that aerosols are not very important to Australian climate. 
+"But when we did these simulations ... without the aerosols we got a completely different rainfall response over Australia.
+"That's suggesting [aerosols are] something we have to take very seriously if we're going to be able to predict climate change and not simply treat it as solely a greenhouse gas problem, because it clearly is not."
+
+Prefer to stay up late? It's your inner creativity speaking
+Do your best work at night? Take solace as new research suggests that night owls are more likely to be creative thinkers.
+Scientists can't yet fully explain why evening types appear to be more creative, but they suggest it could be an adaptation to living outside the norm.
+"Being in a situation which diverges from conventional habit, nocturnal types often experience this situation, may encourage the development of a non-conventional spirit and of the ability to find alternative and original solutions," says Professor Marina Giampietro, lead author of a study to be published in the February 2007 issue of the journal Personality and Individual Differences.
+The Italian researchers, from the Department of Psychology at the Catholic University of the Sacred Heart in Milan, studied 120 men and women of varying ages.
+A self-report questionnaire evaluated degrees of morning and evening dispositions. In fact, true morning and evening-oriented people are actually rare, since most of us fall somewhere in between.
+Once the subjects were categorised into either morning, evening or intermediate types, they underwent three tests designed to measure creative thinking.
+During the first activity, test subjects were asked to draw and title a picture based on an image shown by the researchers.
+For the second activity, called incomplete shapes, test subjects added lines to create pictures out of straight and curved lines. They then were asked to give their pictures a title.
+The final test was similar, only this time the individuals were presented with 30 pairs of vertical lines.
+Scientists scored each completed activity on originality, elaboration, fluidity and flexibility factors.
+Evening types aced each test based on these criteria, while morning and intermediate type people struggled to get scores over 50.
+The researchers also discovered that age didn't curtail creativity.
+"Our study supports the notion that creative characteristics persist in aged people," the scientists write.
+Night owl? Blame your brain
+Hans Van Dongen, associate research professor at the Sleep and Performance Research Center at Washington State University, helped to discover the biological explanation behind morning and evening types.
+He and his colleagues found that a small group of brain cells, called suprachiasmatic nuclei, emit signals to the body that synchronise the time of day.
+This biological clock runs two hours ahead in morning types and two hours later in evening types.
+Morning and evening-oriented people may follow other schedules, due to work, school and other demands, but their preferred schedule is more in sync with this internal clock, which may be partly determined by genetics.
+Van Dongen says that the finding about creativity and evening types is "certainly novel, and one I would not have expected on biological grounds".
+He suggests that the observed differences in creativity might have to do with the fact that evening people also tend to be more extroverted than morning and intermediate types.
+"One could reasonably envision a link between the personality trait of extroversion and the finding of creativity," Van Dongen says.
+
+The Australian Alps had the thinnest and shortest snow season since at least 1982
+Planet Earth had its sixth hottest year on record and a deluge of severe record-breaking weather, according to a new report.
+The findings come from the World Meteorological Organization's (WMO) preliminary report on global climate data for 2006, released today.
+"All over the world we are starting to see extreme weather records being broken," says Dr Michael Coughlan, head of the National Climate Centre at Australia's Bureau of Meteorology, which contributed to the WMO report.
+"While we have had severe events in the past, there does seem to be a pattern now of increasing severity."
+This year was the sixth hottest on record and 2005 was the second hottest.
+"It's unequivocal that temperatures are rising," says Coughlan.
+He says the WMO compared this year's temperatures with instrumental records dating back to 1861 and palaeoclimate data extending back thousands of years.
+Drought
+High temperatures and low rainfall through 2006, combined with an El Ni&ntilde;o, brought severe drought to much of southern Australia.
+Major cropping zones had the driest and warmest 5 years on record.
+And the Australian Alps had the thinnest and shortest snow season since at least 1982, and anecdotally for at least 40 years.
+"In terms of the rainfall this is certainly one of the worst drought on record," says Coughlan.
+Southeastern Australia also had record low temperatures in May and June and severe crop-damaging frosts in late September and mid-October.
+This year's drought followed a 5 to 10 year decline in rainfall in southern and eastern Australia.
+And in the case of southwest western Australia the downward trend in rainfall extends back 20 to 30 years, says Coughlan.
+He says that in this area research by the Indian Ocean Climate Initiatve has linked the decline in rainfall partially to greenhouse gas-induced global warming.
+But in southeastern Australia, where the downturn in rainfall is relatively recent, this link has yet to be made, says Coughlan.
+Australia was not the only place affected by drought, says the WMO report.
+Long-term drought was a problem in the US, Brazil, China and southern Africa, where at least 11 million people were affected by food shortages.
+Flooding rain
+The decrease in rainfall leading to drought in some places is accompanied by increases in rainfall elsewhere, leading to floods.
+Overall, the trend in Australia is for increasing rainfall, just not in the agricultural areas.
+Australia's tropical north had its fifth wettest wet season on record and tropical cyclone Larry in March was the strongest cyclone to make landfall in Queensland since 1918.
+Flooding was also a feature globally.
+The Indian monsoon, for example, brought the highest rainfall in 24 hours ever recorded in several locations.
+Meanwhile, the Danube river reached its highest level for more than a century in April 2006 affecting tens of thousands of people in eastern Europe.
+In May, floods in some of the New England area of the US were the worst in 70 years.
+And the Canadian city of Vancouver had its wettest month ever in November.
+Somalia is currently suffering the worst flooding in recent history with some places receiving more than six times the average monthly rainfall, affecting hundreds and thousands of people.
+Last year also saw the largest ozone hole over the Antarctic and a continued sharp decrease in Arctic sea ice. Over 60,000 square kilometres (about two thirds the size of the state of New South Wales) is being lost a year.
+
+Experts say the reduced HIV risk may be because cells on the inside of the foreskin, the part of the penis cut off in circumcision, are particularly susceptible to HIV infection
+Circumcising men cuts their risk of being infected with HIV in half, and could prevent hundreds of thousands or even millions of new infections, researchers say.
+Circumcising men worked so well that the researchers stopped two large clinical trials in Kenya and Uganda to announce the results, although they caution that the procedure does not make men immune to the virus. 
+Public health leaders hailed the results as pointing to a potentially powerful way to reduce HIV infections in Africa, the continent hardest hit by AIDS. 
+"It does have the potential to prevent many tens of thousands, many hundreds of thousands and perhaps millions of infections over coming years," says Dr Kevin De Cock, director of the World Health Organization's Department of HIV/AIDS. 
+The US National Institutes of Health (NIH) study in Kisumu, Kenya, involving 2784 men aged 18 to 24 showed a 53% reduction of HIV infections in circumcised men compared to uncircumcised men.
+A parallel study involving 4996 men aged 15 to 49 in Rakai, Uganda, showed circumcised men were 48% less likely than uncircumcised men to become infected. 
+Researchers previously noticed that in places where circumcision is common, HIV is less common. 
+Results of the first major study on the issue were reported last year out of South Africa, with researchers seeing a 60% reduction in HIV risk for circumcised men. Researchers view the results of the new trial as strong confirmation. 
+Dr Anthony Fauci, director of the NIH's National Institute of Allergy and Infectious Diseases says the institute ended both trials early and offered circumcision to all men involved in them. The trials began in 2005 and were due to go until mid-2007.
+HIV prevention
+"These results indicate that adult male circumcision could be an important addition to an HIV prevention strategy for men. Male circumcision can lower both an individual's risk of infection and hopefully the rate of HIV spread through the community," Fauci says. 
+Experts say the prevalence of male circumcision varies by region in African countries south of the Sahara, with large numbers of men in some areas remaining uncircumcised. 
+Fauci says while the initial circumcision benefits would be fewer HIV infections in men, the practice could lead to fewer women getting infected in parts of the world like Africa where the virus is passed largely through sex between a man and woman, not homosexual sex. 
+Another study is under way in Uganda assessing HIV infection risk for women with circumcised partners. 
+Experts say the reduced HIV risk may be because cells on the inside of the foreskin, the part of the penis cut off in circumcision, are particularly susceptible to HIV infection.
+HIV also may survive better in a warm, wet environment like that found beneath a foreskin. 
+Circumcision just part of the story
+Fauci says circumcision is not completely protective "and must be seen as a powerful addition to, not a replacement for, other HIV prevention methods".
+He says the benefits could be negated by small decreases in condom use by men or if men add more sexual partners. 
+"These results only apply to men where the risk of HIV transmission is through the penis. Transmission by injection drug use or receptive anal intercourse will not be affected by adult male circumcision," Fauci adds. 
+De Cock says public health experts might encounter cultural and social barriers in parts of Africa to male circumcision. 
+Of the 39.5 million people worldwide infected with the human immunodeficiency virus, 24.7 million are in sub-Saharan Africa. About 25 million people have died from AIDS since it was first identified a quarter century ago.
+
+The newly discovered glider was an agile flyer and had pointed, sharp teeth that it used to eat insects
+Gliding squirrel-like mammals that lived with the dinosaurs at least 130 million years ago may have conquered the skies around the same time as birds, or even earlier, scientists say.
+The newly discovered flyer, called Volaticotherium antiquus or ancient gliding beast, extends the earliest record of gliding flight for mammals to at least 70 million years earlier than once thought.
+A fossil of the creature, which represents a previously unknown group of mammals, was found in rock beds in northeastern China. 
+"It is the first fossil record of a gliding mammal in the Mesozoic, in the age of the dinosaurs. Previously we have had no fossil record of a mammal that had the ability of flight," says Dr Jin Meng, a palaeontologist at the American Museum of Natural History in New York.
+The find suggest other mammals from the Mesozoic era, from 248 to 65 million years ago, could have been much more diverse than scientists think. 
+Meng and his colleagues describe the flying mammal in the journal Nature.
+It is thought to be one of the most important discoveries of a major mammalian group since a review of Mesozoic mammals by Richard Owen in 1871.
+"This mammal is so different from what we know of Mesozoic mammals. So we think it presents a new branch of early mammals," Meng says. 
+The oldest previously known gliding mammal was a rodent. Bats took to the skies with powered flight about 51 million years ago. But the new gliding mammal is not a direct ancestor of any other living mammals.  
+Small agile glider
+The fossil shows the newly discovered mammal weighed 450 grams, was an agile flyer and had pointed, sharp teeth that it used to eat insects. 
+Toe bones suggest it was also able to climb trees, critical for a glider to reach heights from which to take off. 
+It had a large skin membrane from its fore to hind limbs that acted like an aerofoil during flight. There is also evidence of fur on the membrane and other parts of its body.
+A long tail could have acted as a rudder during flight. 
+Fossils of gliding animals are extremely rare. The scientists say the fossil record for gliding mammals is so scant because the small creatures are poorly preserved, particularly their gliding structure.
+"Because they are small mammals and live in forests it is harder for them to be preserved as fossils," says Meng.
+
+Golden coloured cocker spaniels are supposed to be more aggressive than black ones. But are other influences more important in shaping a dog's personality?
+A dog's colour reflects a pooch's personality, scientists say, at least in one breed, the English cocker spaniel.
+The latest study, recently published in the journal Applied Animal Behaviour Science, shows that golden/red English cocker spaniels exhibit the most dominant and aggressive behaviour.
+Black dogs in this breed are the second most aggressive, while particolour (white with patches of colour) are more mild-mannered.
+Earlier research suggests that hair colour is also linked to behaviour in labrador retrievers.
+For this breed, the most aggressive are the yellow ones, the next most aggressive are the black dogs and the least aggressive are the chocolate coloured ones. 
+The behaviour-hair colour connection is likely due to related genetic coding that takes place during the pup's earliest life stages, according to lead author Dr Joaqu&iacute;n P&eacute;rez-Guisado.
+"Maybe the link [to coat colour] is due to the fact that the ectoderm [one of the three primary germ cell layers] is where the skin and central nervous system originate in the embryo," he says.
+P&eacute;rez-Guisado, a Spanish researcher in the Department of Medicine and Animal Surgery at the University of Cordoba, and his colleagues measured levels of dominance and aggression in 51 seven-week-old English cocker spaniel puppies that were either full siblings or half siblings.
+The tests looked at how quickly a person could capture a puppy's attention, how well puppies followed the individual, how the dogs behaved while restrained, how they exerted their social dominance and what they did when they were lifted off the floor.
+In many cases, the golden-coloured dogs resisted human contact and even tried to bite the tester, while the particolour pups often wagged their tails and seemed to enjoy the attention.
+While genes control coat colour and appear to predispose behaviour in certain dogs, P&eacute;rez-Guisado says how dogs are raised plays the biggest role in behaviour. 
+He shows that environmental factors account for 80% of dominant, aggressive personalities while genes only influence 20% of dogs' demeanours.
+"It is very important to give the dog an optimum and suitable environment in order to have a dog with a low dominance aggressive behaviour level," he says.
+"For that reason, owners are primarily responsible for this undesirable dog behaviour."
+Hardly surprising
+Canine behaviourist and trainer Wendy Volhard and professional breeder Carolyn Sisson, who is president of the English Cocker Spaniel Club of San Diego, California, both say they're not surprised by the findings.
+They say that the link between coat colour and behaviour has been "a well-known, old wives' tale" for years.
+Although they both think there is "some truth to the recent findings", Sisson believes a dog's genetic lineage, going back many generations, is a better indicator of temperament than colour.
+Sisson says there are 29 recognised different coat colours for English cocker spaniels, and combinations other than golds mating with golds can result in a golden dog.
+"It's the line breeding out of puppy mills in England that probably resulted in the dominant traits," Sisson says.
+"The very best and worst of my dogs have been spaniels. They seem to cover every behavioural extreme," she adds.
+Looking at DNA
+P&eacute;rez-Guisado and his colleagues next plan to study the English springer spaniel and English cocker spaniel genomes to pinpoint common genes associated with so-called dog rage and colouration.
+Earlier research has also found that hair type may indicate a dog's temperament.
+In a study, wiry-haired mini dachshunds were often more feisty than their mellower, long-haired cousins.
+
+Hundreds of planetary nebulae with intriguing shapes like this helix nebula have been found by an Australian-led team
+The discovery of over 1000 glowing planetary nebulae could help balance cosmic accounts, says an international team of astronomers.
+The researchers say that their discovery could help them calculate what happens to stars' missing matter, mass that seems to be 'lost' when they die.
+Dr Quentin Parker, of Australia's Macquarie University in Sydney, and colleagues, say they have found 900 new planetary nebulae in the Milky Way and 500 in the neighbouring Large Magellanic Cloud.
+"Planetary nebulae are the death throes of stars," says Parker, who is also with the Anglo-Australian Observatory. 
+They are glowing regions of ionised gas that average-sized stars like our Sun throw off when they get old.
+The gas the dying star ejects interacts with the environment around it, such as the interstellar medium, to form weird and wonderful shapes.
+These have been given names like the cat's eye, hourglass, helix, ant and red spider.
+Missing matter
+Studying planetary nebulae helps tell us about how stars' matter is recycled from old to new stars.
+Nebulae last for tens and thousands of years so it's important for astronomers to study both young and old ones. 
+In general, it has been a lot easier for astronomers to find younger nebulae because they glow brighter.
+But Parker and colleagues have been able to find the fainter older ones and are now confident that they have representative sample of different ages, especially of nebulae close to our Sun.
+The mystery about dying stars is that they seem to lose much more mass than what appears to be thrown off in their nebulae. Some 85% of the mass appears to be unaccounted for.
+Parker hope that analysing the hundreds of new nebulae discovered will help explains where the extra mass goes.
+In the team's more detailed study of the Large Magellanic Cloud the team has found numerous extremely faint haloes around 60% of the planetary nebulae there.
+
+Tapping Boswellia tree for frankincense in Eritrea
+If Jesus was born today, the three wise men might have had to substitute frankincense for another gift, according to new research suggesting that production of the fragrant substance is in trouble.
+Frankincense, an aromatic hardened wood resin obtained by tapping Boswellia trees, has been an ingredient in perfumes and incense for thousands of years.
+The Bible says that at Christmas, the magi brought gifts to Jesus of gold, frankincense and myrrh. 
+Now ecologists from the Netherlands and Eritrea warn that current rates of tapping frankincense from Boswellia trees are endangering sustained production of the aromatic resin.
+Writing in the December issue of the Journal of Applied Ecology, Professor Frans Bongers of Wageningen University says that over-tapping the trees results in them producing fewer, less viable seeds.
+And production, in the Horn of Africa, is declining because Boswellia woodlands are failing to regenerate.
+The ecologists hypothesise that poor regeneration, due to intensive tapping, means trees are diverting too much carbohydrate into resin at the expense of reproductive organs such as flowers, fruit and seeds.
+They tested the theory by looking at how many seeds were produced by intensively tapped trees in southwestern Eritrea compared with untapped trees, and their germination rates.
+"At all study sites, trees subject to experimental tapping produced fewer flowers, fruit and seeds than trees that were exempt from tapping," Bongers says.
+"Furthermore tapped trees produced smaller fruits with seeds of lower weight and reduced vitality than non-tapped trees."
+The ecologists suggest changing the way trees are tapped, by reducing the number of tapping points per tree and enabling rest periods, would help ensure production is sustainable.
+"In order to control the decline in fruit and seed production, less intensive tapping procedures should be developed," they write.
+"As our results show that six tapping points per tree are already having a negative impact, we suggest reducing the number of tapping points.
+"New tapping regimes should also include rest periods when there is no resin harvesting to allow the trees to recover."
+The study is the first to show the fragile relationship between extracting wood exudates and tree regeneration in natural populations.
+
+Embryonic stem cells have been harvested from mouse embryos produced without sperm
+Mouse embryos created through a 'virgin birth' process called parthenogenesis show that egg cells can be a source of valued embryonic stem cells, researchers say. 
+The cells can be closely matched to the immune system of the recipient, making them a potential source for transplants, the researchers report today in the journal Science. 
+There are fewer obstacles to developing these stem cells than by using cloning technology, also called somatic cell nuclear transfer, researchers say. 
+"I think it is a much more real-world possibility than nuclear transfer," says Dr George Daley of the Children's Hospital and Harvard Medical School in Boston, who led the study. 
+If the experiment could be reproduced in humans, such cells might provide an alternative way to produce tailored tissues for transplanting, or for studying disease, Daley says. 
+"We are aggressively trying to produce human parthenogenetic embryonic stem cells," he says. 
+How did they do it?
+The researchers say they have produced dozens of genetically matched mice embryonic stem cell lines by means of a novel procedure called parthenogenesis.
+The word comes from Latin and Greek roots meaning virgin beginning and the process occurs when an egg cell starts dividing to produce an embryo without using sperm to fertilise it. 
+The researchers generated stem cells from unfertilised mouse eggs, screened them to ensure they would not be rejected by the rodent's immune system and then injected them back into the mouse. 
+The customised cells were successfully transplanted and yielded many, but not all, types of specialised tissue, possibly because of the absence of any male DNA. 
+The study establishes the principle of using unfertilised eggs as a source of customised embryonic stem cells that are genetically screened to ensure they carry the genes that allow the recipient's immune system to recognise them, making them fit for transplantation therapies.
+Scientists have experimented with parthenogenesis in mice before, but this is the first time that the procedure has yielded the embryonic stem cells or so-called master cells that have the potential to develop into any other type of cell in the body. 
+The study's authors are particularly encouraged because the unfertilised mice eggs produced embryonic stem cells 70% of the time.
+This suggests, the researchers say, that this technique is a much more robust and effective way of generating this highly sought-after genetic material than the current alternative, nuclear transfer. 
+Daley says the cell lines could also be studied for a better understanding of the basic biology of disease. 
+"For instance, a woman with a genetic condition - some kind of early-onset Parkinson's, bone marrow failure - you could use them as an in vitro model of the disease," he says.
+Still, Daley cautions that there are safety concerns with the procedure, which requires the egg to be chemically tricked into spitting out half its genetic material, leaving it with one set of female chromosomes. 
+In particular, tissue obtained in this way can carry some risk of cancer and abnormal growth. 
+"We'll have to demonstrate the safety and durability of cells from parthenogenetic embryonic stems cells before we could imagine any clinical use," says Daley. 
+Human eggs?
+Still, Daley and his team have begun experimenting with the procedure in human eggs, using eggs discarded by women undergoing in vitro fertilisation treatment at Boston's Brigham and Women's Hospital.
+So far, they have not been successful in isolating human embryonic stem cells from these eggs, which are typically 25 hours old by the time they reach the laboratory.
+The research team plans to recruit female volunteers to donate their eggs for research purposes a year or so from now, with the hope that these eggs will deliver better results.
+
+Flares from the Sun are random events but are usually only big at high points in the cycle of solar activity, when this image was taken
+Communication systems are being disrupted by the effects of an unusually large solar explosion that started lashing the Earth this week.
+The explosion could also cause spectacular auroras in the night skies as far north as Sydney, weather permitting.
+Dr David Cole, director of the Australian Government's space weather service, says the massive solar explosion as the Sun is supposed to be in a fairly quiet phase.
+"We didn't expect anything in particular and suddenly this turns up and it's really fierce," says Cole, of IPS Radio and Space Services in Sydney.
+When magnetic fields in the Sun coalesce in dark regions called sunspots they can explode sending a blast of radiation. Such solar flares reach Earth within minutes.
+This is followed by a cloud of plasma or coronal mass ejection (CME) that takes a day or so to reach Earth.
+The flare and CME alter the ionosphere, the outermost part of Earth's atmosphere, and cause problems with communication systems.
+Unpredictable
+Although solar explosions are random, they are more likely to happen when the Sun is most active, during what is called a solar maximum that happens every 11 years. But there is currently a solar minimum.
+Cole says solar flares are hard to predict because there are no models of how they work.
+While Coles' agency suspected something might happen when they saw a sunspot pointing directly at the Earth and a build up in magnetic fields, they couldn't tell exactly if or when an explosion would occur.
+"It's like someone snapping their fingers, you don't know when they're going to do it," he says.
+GPS and short-wave communications blocked
+Cole says the solar flare that reached the Earth mid-week, had possibly the strongest emission at 1.4 gigahertz ever seen, matching almost exactly the wavelength GPS satellites use. 
+He says communication with GPS navigation satellites in the lower ionosphere was blacked out for up to two hours.
+Short-wave radio communications, used by defence forces, aviation and emergency services, were also affected, says Cole. Such communications pass through or bounce off the ionosphere. 
+But Cole stresses air traffic control does not rely on short-wave communication.
+Fire fighters affected?
+Another CME reached Earth today and Cole predicts its effects on short-wave communications will last throughout the weekend.
+It might also affect short-wave communication of some personnel currently fighting Australia's severe bushfires.
+He says his agency will let such emergency services know which frequencies will be unaffected by the CME so they can use these instead.
+Cole says electricity grids close to the poles could also be disrupted today by the CME.
+Cole says the same sunspot produced caused less serious explosions earlier this month and may cause another in around two weeks time.
+Spacewalkers take cover
+While humans on Earth are protected from the effects of solar explosions, those in space are vulnerable, says Cole.
+For instance this week astronauts on the shuttle Discovery and the International Space Station have been sleeping in protected areas and may need to cut planned spacewalks short if radiation levels get too high.
+
+With the new system, individual sensors in a network detect an environmental condition, like temperature, and tell their neighbouring sensors about it. This creates 'clones' that perform tasks based on what their neighbours are doing or sensing
+It has the classic elements of a good spy story: secret agents that infiltrate a network and clone themselves to do the work of many. But this story has a happy ending.
+The agents in question are mobile, self-contained pieces of software that can take over sensors in a wireless network and direct them to accomplish specific tasks.
+The technology could help fight fires, monitor environmental conditions, or even help blind people navigate buildings.
+"Our software is the first to allow this flexible sharing of a sensor network infrastructure," says Professor Gruia-Catalin Roman, chair of the department of computer science and engineering at Washington University in St Louis.
+Most existing wireless sensor networks are built with small devices called motes.
+Each mote includes a battery, a computer, a radio and a sensor that monitors variables such as light, vibration and temperature, takes pictures, or listens for sounds.
+Such networks can consist of hundreds or even thousands of motes, and they can be placed just about anywhere it might be useful to pick up information from the environment.
+Most of them perform a single task, for example monitoring temperature or vibrations in the air. Re-tasking generally requires configuring each sensor anew.
+"This is a major problem. Since these systems exist in the real world, the dynamics and unpredictability often require new solutions," says Professor Jack Stankovic of the University of Virginia in Charlottesville, who is not associated with the research.
+To overcome that limitation, Roman, colleague Assistant Professor Chenyang Lu and their doctoral student Chien-Liang Fok have developed a software system called Agilla.
+Once equipped with the software, individual sensors in a network can detect an environmental condition and communicate with the neighbouring sensors.
+This creates 'clones' that perform tasks based on what their neighbours are doing or sensing.
+In laboratory experiments, Roman and his colleagues used the agents to monitor simulated fires and help robots navigate around them.
+In a real-life situation, a firefighter could potentially tap into the network with a PDA and learn where the fire is and how intense it is.
+"Agilla is small enough to fit on motes, general enough to support many kinds of functionality. I think it is also efficient enough to be viable," says Stankovic.
+
+Nanowires can function as highly sensitive tuning forks, scientists say
+Scientists say they have made the world's strongest nanowire, reaching the theoretical limits of what they'd planned to build.
+The nanowire, which is about 1000 times thinner than a human hair, is so strong it could support 16 African elephants if it was scaled up to the size of a child's finger, says Associate Professor John Sader from Australia's University of Melbourne.
+Sader is part of an international team of scientists that grew the semiconducting nanomaterial, publishing the results in the journal Nano Letters.
+"The ultimate strength we report is the highest recorded for any semiconductor material system and is at the theoretically predicted limit," says Sader, who was involved in measuring the strength of the wires using an atomic force microscope.
+"This indicates that these nanowires are near perfect materials." 
+Experts say that such nanowires could one day be used to make electrical and electromechanical devices like environmental sensors or even ultra-precise clocks.
+To built a nanowire
+The nanowires were built from germanium, an element the researchers say has similar chemical properties to tin.
+They built the material on a surface coated with gold nanocrystals, which allowed the germanium to nucleate and grow.
+They then tested the strength by placing it across a small trench and manipulating it sideways.
+They found it could bend and stretch further than any other nanowire anyone had ever made, sustaining 15 gigapascals before snapping.
+This was roughly the same as the predicted ultimate force, compared to many other semiconducting nanowires, which snap at just 15% of their theoretical limits.
+If the wire was one centimetre in diameter it could hold up to 100 tonnes without breaking, he says.
+This resilience will result in failproof nanodevices, says Sader, adding it is not theoretically possible to make a stronger nanowire.
+"This exhibits the theoretical limits, so this is basically it," he says.
+Tuning forks and metronomes
+Professor Paul Mulvaney from the University of Melbourne's school of chemistry, who wasn't involved in the research, says the nanowires could be used as sensors to detect gases, air pollutants or biological agents.
+This is because they function as super-sensitive 'tuning forks' that change frequency when molecules become attached to them.
+"Because the wires are so small, they can detect very small amounts of materials absorbing onto their surface," he says.
+They could also be used as nanoscale metronomes that vibrate in high-frequency timing devices or in computer chips, he says.
+Germanium nanowires are also ideal candidates for making optical devices like light-emitting diodes and tuneable lasers, Mulvaney says.
+
+The batfish has literally emerged from the blue as a potential saviour of dying coral reefs
+A fish that gatecrashed an experiment in Australia's Great Barrier Reef has surprised scientists by emerging as an unexpected weapon against the worldwide decline of coral reefs.
+Scientists from the Australian Research Council Centre of Excellence for Coral Reef Studies (CoECRS) had been studying ways of reversing the effects of coral bleaching at a reef near Orpheus Island in the World Heritage listed marine park.
+Part of the research involved generating a bloom of the tropical kelp sargassum weed and seeing if local weed eating fish would chomp their way through it, says CoECRS director Professor Terry Hughes.
+While herbivorous species like the parrotfish and surgeon fish only nibbled disinterestedly at the algae, the batfish (Platax pinnatus) turned up and cleared the weed within two months.
+"The surprising finding ... was that a different group of fish was responsible for reversing the algal bloom," Hughes says.
+"Batfish are normally considered to be plankton feeders so we were amazed when we captured on video the effects those fish were having."
+Chief investigator Professor David Bellwood of the CoECRS and James Cook University says the batfish's voracious appetite for weed saved the coral from being choked to death.
+"In five days they had halved the amount of weed. In eight weeks it was completely gone and the coral was free to grow unhindered," he says.
+Weed warriors
+Bellwood says declining coastal mangroves serve as nurseries for batfish, which are found in reefs around the world.
+This highlights the need to preserve mangroves and protect these accidental weed warriors, he says.
+Other reef weed-mowers like the green turtle and dugong, are both seriously endangered, he says.
+"If Platax is the last grazer of dense weedy stands on inshore coral reefs and it goes into decline the capacity of these reefs to recover ... could be lost," he says.
+Reporting in the journal Current Biology today, Bellwood describes the batfish as a "sleeping functional group", or a species with a hitherto unrecognised role in reef life.
+Adapting to climate change
+The study is the first extensive demonstration of the role of fish in promoting the recovery of coral reefs, Hughes says.
+He says it shows that reefs can adapt to climate change, which has been linked to coral bleaching and subsequent overgrowth of weed.
+"We're only beginning to scratch the surface in terms of the changes that climate change is already causing," he says.
+"I am of the opinion that coral reefs have already started to adapt ... I think we'll see a shift in the abundance of particular species depending on their ability to respond."
+
+Designers and engineers are sharing information online about how to build a better car, free from patents and profit margins
+The open source movement responsible for software like Linux and the browser Firefox is proving contagious. Now a German entrepreneur is applying the same approach to designing a car.
+Former BMW employee Markus Merz, who now owns an automobile consulting firm in Dingolfing, Germany, calls his project Oscar, shorthand for Open Source Car.
+The idea behind open source development is to allow anyone to copy, modify and redistribute ordinarily secret information about a technology without paying royalties to the original developers.
+The project, which Merz calls his hobby, is bringing together automobile engineers, designers and other experts on online forums to exchange ideas on how to improve mobility, specifically car design. 
+The hope is that, unrestrained by patents and other conventional restrictions such as profit margin, marketing and technology, a community of experts will come up with fresh solutions.
+"We [usually work] in front of the computer to generate stuff that people in front of a computer will use. It's boring," says Merz.
+"It would be a great idea to combine the idea of open source with the idea of hardware, and a car is hardware that is interesting."
+Designers share ideas online 
+A website serves as headquarters for the concept car. Participants interact according to a few simple rules about performance specifications.
+For example, the car will be about 4 metres long and 2 metres wide, and will have four doors. It will be powered by electricity and have a maximum speed of about 150 kilometres per hour.
+Participants discuss their ideas on online forums organised into four main topics: integration, which includes design, package and distribution; modules, which includes discussion of the body, engine and safety systems; tools, which includes conversations about computer-aided design tools and simulations; and network, where participants discuss potential partnerships.
+A group of technicians heads each forum to ensure that the best ideas are moved forward to computer modelling and testing. From there, anyone, including car manufacturers, will be encouraged to build the car.
+There will be no patents, and no proprietary data.
+"The most effective tool you can have to get anything done is passion and creativity and that needs to be unleashed, and then it's much more powerful than money," says Lukas Neckerman, head of automotive business development at a financial services company in Munich.
+Oscar is also a hobby for Neckermann, who is responsible for communications.
+Encouraging creativity
+Mechanical engineer Achim Schillak agrees that people have a desire to contribute their ideas to innovative projects, and if they can't do that in their current occupation, they will find another outlet.
+Schillak wrote a case study about Oscar while he was studying business management at New York University.
+But he believes that there are some limitations applying the open source approach to cars.
+"After design studies and calculations, you have to build a prototype and crash test it and that is a major difference to developing some software," says Schillak.
+And Oscar is not set up to build the car. But Merz has faith that any of several small auto manufacturers could eventually take the concept to its 3D form.
+"The greatest success for me would be if I can ride in this car," says Merz.
+
+Should people take cod liver oil capsules, which are rich in vitamin D, to prevent MS?
+A new study provides the most compelling evidence yet that vitamin D, the so-called sunshine vitamin, may protect against the neurological disease multiple sclerosis (MS). 
+Harvard University researchers who reviewed the medical data of more than seven million US military personnel found the risk of MS fell dramatically as the level of the vitamin circulating in the blood rose. 
+The effect was only seen in Caucasians; the data in the study for African Americans and people of Hispanic descent was inconclusive. 
+The relationship was particularly strong in the under-20 age group, according to the study published today in the Journal of the American Medical Association.
+Individuals who ranked in the top 20% of the sample for vitamin D levels had a 62% lower risk for the chronic autoimmune disease than those in the bottom 20%. 
+The study also found that there was a 41% decrease in risk for MS with every increase of 50 nanomoles per litre of circulating vitamin D. 
+"The study strongly suggests that vitamin D has a protective effect, and one which could potentially prevent thousands of cases of MS," says co-author Alberto Ascherio, associate professor of nutrition and epidemiology at the Harvard School of Public Health.
+The findings add to a growing body of evidence that vitamin D could reduce the incidence of the incurable condition. 
+But Ascherio says it is still insufficient to make the case for an increase in the recommended daily dietary intake of vitamin D.
+"It's important to establish whether it's a true causal relationship," says Ascherio.
+He says the question should be urgently addressed by means of a trial that would enrol volunteers and assign them to take the supplement. 
+MS is a chronic inflammatory disease of the central nervous system that afflicts some two million people worldwide.
+It is more common among people with northern European ancestry, according to the US National Multiple Sclerosis Society.
+The illness can be relapsing and remitting or progressive, with symptoms that range from fatigue and slurred speech to tremors, stiffness, poor coordination and in the most severe cases paralysis.
+Vitamin D, dubbed the sunshine vitamin because it is naturally produced in skin that is exposed to the Sun's ultraviolet rays, is thought to rein in the overzealous immune system cells that cause the condition. 
+For more information on MS, including information for patients and their carers, see the MS Australia website.
+
+Humans may be able to understand a dog's bark because all mammals speak a universal language
+What do dog barks have in common with bird tweets and human baby cries?
+All appear to communicate basic emotions, such as fear, aggression and submission in somewhat the same acoustic way, according to a new study in the journal Applied Animal Behaviour Science.
+The find suggests a primitive communication system may unite virtually all mammals.
+The theory could help explain why previous research has found that many mammals, including humans, understand the vocalisations of different species.
+For example, a study in the journal Language Communication shows young children can identify simple emotions conveyed in macaque calls.
+For the recent research, Professor P&eacute;ter Pongr&aacute;cz and colleagues studied how well people could describe the emotional content of several artificially assembled bark sequences.
+The barks were based on sounds made by a mudi (a Hungarian herding dog) and covered five emotional states: aggressiveness, fear, despair, playfulness and happiness.
+Pongr&aacute;cz, a professor of ethology at E&ouml;tv&ouml;s Lor&aacute;nd University in Budapest, Hungary, and his team then compared the listeners' answers to the barks' acoustic features.
+The scientists discovered that changes in three basic sound qualities - tone, pitch, and the time between barks - determined how listeners perceived the barks.
+In general, high-pitched barks with longer intervals between each bark were rated as less aggressive than lower-pitched barks heard in frequent succession.
+Just like humans
+Human babies make similar changes in sound quality when they cry, except frequency range appears to be more important than pitch when they express their needs.
+This link between pitch or frequency and perceived emotion appears to carry across many different species, according to Pongr&aacute;cz, who cited an earlier theory proposed by avian expert Professor Eugene Morton.
+"His basic argument was that, according to the general physical laws, larger bodies emit sounds characterised by lower frequencies and these are also noisier/atonal. Thus receivers can predict the size of the sender," Pongr&aacute;cz and his team write.
+"This relationship could have formed the basis of an evolutionary ritualisation process whereby low-pitched vocalisations tended to signal aggression because larger animals are more likely to win contests ... and high-pitched vocalisations became predictors of submission or friendly intent."
+Since the people in the dog study also linked barks signifying despair, happiness and playfulness, the researchers suspect dogs and humans share a unique ability to communicate with one another that goes beyond the proposed universal mammal 'language'.
+The scientists believe years of domestication have improved the way that dogs, versus their wolf ancestors, can communicate with us.
+They point out that such communication isn't limited to vocalisations. It also includes visual signals, such as changes in looks.
+Common house cats also appear to have evolved improved means of communicating with humans, according to a study conducted by Cornell University researcher Nicholas Nicastro. Cats, however, seem more intent on manipulating us.
+"Though they lack language, cats have become very skilled at managing humans to get what they want - basically food, shelter and a little human affection," says Nicastro.
+Alan Beck, professor and director of the Center for Human-Animal Bond at Purdue University, says that we have to be careful not to interpret behaviour according to "our projection of intent".
+But he admits dogs might be able to communicate with us through their barks.
+"As dogs and humans share some basic non-verbal communications, it is very possible that verbal ones also exist," Beck says.
+
+Your music would be grouped in 'islands', which you could see on a screen. The more jazz in your collection, for example, the steeper the contours of the jazz island. And when you hover over the island, you'd see a list of songs floating like clouds
+Music fans are downloading digital music and storing hundreds, if not thousands, of songs onto smaller and smaller devices.
+Yet organising those songs remains a throw back to the days of vinyl, an uninspired structure of artist, album or track.
+Researchers have now developed a program that automatically organises a collection of digital music files into a virtual landscape.
+Instead of digging deeper and deeper through categories and subcategories of songs, you fly over an archipelago of sound-specific islands.
+"It could work like a flight simulator," says Peter Knees, a PhD candidate and project assistant at Johannes Kepler University in Linz, Austria.
+"You see landmarks that relate to style. If you dive deeper, it will reveal artists and then deeper to see individual songs."
+Such a visual experience with digital files could fuel the music industry in new ways, says Ichiro Fujinaga, associate professor at the Schulich School of Music at McGill University in Montreal, who is not associated with the research.
+"Good solutions may allow vendors to sell more music," he says.
+So far, the solution Knees and his team propose organises about 500 music files. It's capable of analysing tens of thousands, but the researchers are keeping things simple while they make refinements.
+The software analyses certain features from the audio signal, such as how much bass or treble exists and sound patterns that have to do with rhythm and tempo. Then the program clusters similar sounding pieces into regions of music.
+The more similar pieces the user owns - let's say, Latin jazz - the higher the terrain on the Latin jazz island.
+The user flies over the landscape using a joystick. As she approaches an island, she will hear an auditory impression of the musical style of the region. She also sees song titles, artist names, and even images floating like little clouds above the landscape.
+If she wants to hear a specific song, she simply hovers over it. Or if she wants to hear anything from Latin jazz, she hovers over the region.
+There are some things the software doesn't address, Fuinaga points out, such as the user's profile (is she a teenager or an opera buff?) or the listening context (is the person driving, showering on a date?).
+And as good as any 3D music interface might be, some people are still sceptical about whether it's really necessary. But then, is a US$500 mp3 player really necessary?
+Knees and his team are currently developing the program for a public exhibition at an Austrian science museum that specialises in new media technology.
+Museum goers will be able to play with music files already stored in the computer or download their own files to see what their collection looks like.
+
+Latest image of the first light in the universe
+Fresh evidence of the first objects to emerge after the Big Bang has left scientists debating what these could be.
+Researchers say the cosmic glow could be the first stars or quasars, but are not sure which.
+Dr Alexander Kashlinsky and colleagues at the  NASA Goddard Space Flight Center will report their findings in the 1 January issue of The Astrophysical Journal.
+Using NASA's Spitzer Space Telescope, the researchers analysed infrared radiation from deep space.
+They first removed the bright signal of recent galaxies in the foreground to detect the the ancient background glow.
+The researchers saw clumps in this infrared background radiation they believe comes from the first objects to emerge from the Big Bang.
+"Observing the cosmic infrared background is like watching distant fireworks from within a brightly lit city," says Kashlinsky. 
+"It's as if we have turned off the city lights one by one to see the bursts more clearly."
+Building on their study published in the journal Nature last year, the researchers say they could be picking up light from the earliest stars, stretched to infrared wavelengths by the expansion of the universe.
+Alternatively, they say the distant glow could be from quasars - large black holes that consume enormous amounts of gas and debris and re-emit the materials in powerful burst of energy.
+Less certain the glow comes from stars
+Last year the researchers were reportedly certain the signals from deep space were from the earliest stars.
+Kashlinksy says this was because his team failed to explain that current equipment does not allow the researchers to pinpoint individual sources of the radiation.
+"We did not make this point sufficiently clear in the Nature paper in 2005 and, hence, added a caveat on this in the new papers," says Kashlinksy.
+"While we can't resolve each spark in the fireworks, we can see the large scale structures and their glow."
+
+The way your gut microbes digest food could influence your body weight, scientists say
+Bacteria in your gut may determine whether you are skinny or obese, according to scientists who say that food, exercise and genetics may not be the only things to influence body weight.
+US scientists have discovered that levels of two types of good bacteria in the gut that help to break down foods are different in obese and lean people and mice.
+The finding, reported today in the journal Nature, could lead to a better understanding of why some people may be prone to obesity and help find new ways of preventing or treating it. 
+"Our gut microbial structure should be considered when understanding the elements that might regulate our energy balance and may predispose us to obesity," says Professor Jeffrey Gordon, of the Washington University School of Medicine in St Louis.
+"There is something very startling about the amount of fat you have and the structure of your gut microbial community," he adds. 
+There are trillions of bacteria in the gastrointestinal tract, but two groups called the bacteroidetes and the firmicutes are the most dominant and their proportion varies in lean and obese mice and humans.
+The scientists found that the proportion of bacteroidetes bacteria is lower in obese mice and people than in lean people. 
+But when Gordon and his team studied 12 obese people who followed low-calorie diets for a year, they found their levels of bacteroidetes rose as their weight decreased. 
+"They increased as the weight is lost and in proportion to the amount of weight loss," says Gordon. 
+The results suggest that there may be a microbial component to obesity. But scientists do not yet know if people start out with lower levels of bacteroidetes or firmicutes that may make them prone to obesity. 
+"These are things we are exploring now. What are the signals between the amount of fat and different groups of bacteria that exist in the gut," says Gordon.
+University of Cincinnati researchers, writing in an accompanying commentary in the journal, say:
+"This is a potentially revolutionary idea that could change our views of what causes obesity and how we depend on the bacteria that inhabit our gut. But a great deal remains poorly understood."
+
+This komodo dragon was a 'virgin birth' at London Zoo recently. Another batch is expected at Chester Zoo this Christmas
+Flora, a pregnant komodo dragon living in a UK zoo, is expecting eight babies in what scientists say could be a Christmas virgin birth. 
+Flora has never mated, or even mixed, with a male dragon, and fertilised all the eggs herself, a process culminating in parthenogenesis, or virgin birth.
+"Nobody in their wildest dreams expected this. But you have a female dragon on her own. She produces a clutch of eggs and those eggs turn out to be fertile. It is nature finding a way," says Kevin Buley of Chester Zoo.
+He says the incubating eggs could hatch around Christmas. 
+Parthenogenesis has occurred in other lizard species, but Buley and his team says this is the first time it has been shown in komodo dragons, the world's largest lizards. 
+Scientists at the University of Liverpool discovered Flora had had no male help after doing genetic tests on three eggs that collapsed after being put in an incubator. 
+The tests on the embryos and on Flora, her sister and other dragons confirmed that komodo dragons can reproduce through self-fertilisation. 
+"Those genetic tests confirmed absolutely that Flora was both the mother and the father of the embryos. It completely blew us away because it [parthenogenesis] has never been seen in such a large species," Buley says. 
+A komodo dragon at London Zoo gave birth earlier this year after being separated from males for more than two years. 
+Scientists thought she had been able to store sperm from her earlier encounter with a male.
+But after hearing about Flora's eggs, researchers conducted tests that showed her eggs were also produced without male help. 
+"You have two institutions within a few short months of each other having a previously unheard of event. It is really quite unprecedented," says Buley. 
+The scientists, reporting the discovery today in the journal Nature, say it could help them understand how reptiles colonise new areas.
+A female dragon could, for instance, swim to another island and establish a new colony on her own. 
+"The genetics of self-fertilisation in lizards means that all her hatchlings would have to be male. These would grow up to mate with their own mother and therefore, within one generation, there would potentially be a population able to reproduce normally on the new island," Buley says.
+
+This giant sauropod weighed a massive 48 tonnes, eight times more than Tyrannosaurus rex
+The fossilised remains of a gargantuan plant-eating dinosaur, one of the largest animals ever to walk the Earth, has been found in Spain.
+The giant would have been up to 38 metres long and weighed as much as seven elephants.
+Turiasaurus riodevensis, named after the region and village in Spain where it was found, lived about 145 million years ago, the research team reports today in the journal Science.
+It was a sauropod, the familiar kind of dinosaur with a long neck, long tail and massive body that walked on four stout legs. 
+Sauropods are the largest land animals in Earth's history and this particular one is the largest dinosaur ever found in Europe.
+Previous dinosaurs of this scale have been found mostly in the Americas and Africa. 
+This one is emblematic of a previously unrecognised branch of European sauropod evolution, the scientists say.
+"This discovery is the dream of a palaeontologist," says co-author Dr Luis Alcala of Fundaci&oacute;n Conjunto Paleontol&oacute;gico de Teruel-Dinopolis in Spain. "Really, I'm not dreaming?" 
+The dinosaur came from a time right at the boundary between the latter two periods of the Age of Dinosaurs, the Jurassic and Cretaceous. Relatively little has been known about European dinosaurs dating from then. 
+Scientists believe this dinosaur spent its days munching plants in an area close to the shoreline of the ancient Tethys Sea, forerunner of the Mediterranean Sea. 
+The first bones were found in an abandoned wheat field near the village of Riodeva in northeastern Spain in May 2003, Alcala says. 
+Alcala says it weighed 40-48 tonnes and was 36-38 metres long. Tyrannosaurus rex was a baby by comparison, weighing just 6 tonnes and about 13 metres long.
+The Spanish dinosaur's humerus, the bone in the front leg that extends from shoulder to elbow, was as big as a full-grown man. 
+Turiasaurus rivals the size of the largest known dinosaurs, all sauropods, and its remains were more complete than those of many of them.
+These include the African giant Paralititan, Seismosaurus in North America and Argentinosaurus and Puertasaurus in South America. 
+"It's a tremendously large animal, not quite to the scale of the 'land whales', things like Argentinosaurus and Puertasaurus or Sauroposeidon. But it's pretty darned big," says Dr Thomas Holtz, a dinosaur expert at the University of Maryland who was not involved in the research.
+"This is the first real super-giant from Europe," Holtz says. 
+Other fossils found at the site indicates Turiasaurus lived alongside other dinosaurs, including two-legged meat eaters, other sauropods and plant eaters similar to the armoured Stegosaurus. Turtles and crocodile-like reptiles were also around at the time.
+The researchers say Turiasaurus was more primitive from an evolutionary perspective than other known giant sauropods. 
+The team found 70 pieces of the fossilised remains representing about a quarter of its skeleton, including fragments of the skull, leg, back, toes, ribs, shoulder blade and teeth. 
+Finding most of the key parts, the only vital missing piece was the pelvic girdle, allowed the scientists to ascertain its dimensions and appearance.     
+Other well-known sauropods include Apatosaurus (formerly known as Brontosaurus), Brachiosaurus and Diplodocus.
+
+Researchers have found DNA associated with nanoparticles from kidney stones. Could these strange particles be nanobacteria?
+Researchers who've found strange nanoparticles in a handful of kidney stones say these self-replicating specks may play a role in disease.
+The US researchers are not sure whether these tiny particles, 50 to 100 nanometres across, are living nanobacteria or just some strange non-living self-assembling ball of chemicals.
+"We have some evidence that would support either possibility," says kidney specialist Dr John Lieske of the Mayo Clinic College of Medicine.
+He and colleagues report their findings in the December issue of the Journal of Investigative Medicine.
+At some point in their life about 10% of people will get kidney stones, a painful condition in which calcium deposits clog the kidneys.
+Scientists aren't sure what causes these deposits. But one theory that Lieske and colleagues are investigating is that tiny calcium-covered particles are partly to blame.
+Previous research has found such particles in human serum, urine, renal cysts from patients with kidney disease, as well as in kidney stones.
+Lieske says some researchers dub the particles nanobacteria, and propose they are a new disease-causing agent.
+But Lieske says there is not yet enough evidence these particles are alive.
+Nanoparticle investigation
+Lieske's team isolated the nanoparticles, which have a protein-lipid core surrounded by a calcium phosphate shell, from kidney stones. 
+The researchers grew the nanoparticles in culture over a period of four to eight weeks.
+They found that antibiotics and metabolic inhibitors slowed the particles' growth.
+Then the researchers grew a large batch of nanoparticles, dissolved the calcium shells and extracted proteins and DNA.
+Does all this mean that the nanoparticles are nanobacteria after all? 
+Lieske says it's still too early to say.
+"There definitely is DNA associated with [the nanoparticles]," he says. "But is that a contaminant?"
+He says some fragments of the protein and DNA appear to match known bacteria.
+His team now plans to grow more nanoparticles and see if they can find a unique genetic signature that would prove the nanoparticles are indeed nanobacteria.
+Scepticism
+Geologists and astrobiologists have also considered the possibility of nanobacteria over the years. For instance, understanding the full range of life forms is important in our search for extraterrestrial life.
+Professor Malcolm Walter of the Australian Centre for Astrobiology in Sydney, says there has been much scepticism about nanobacteria.
+
diff --git a/031602408/bin/lib/Store$1.class b/031602408/bin/lib/Store$1.class
new file mode 100644
index 0000000000000000000000000000000000000000..c3886c2d4a6bffc9e388e3a1d6d91ae97dc6504d
GIT binary patch
literal 1236
zcmbtTOK;Oa5dJnVH;zLdO#*~hfdF|nq%EgZkx*15ODP<Jaz#$Eq^?{$vNuQ-e~Am1
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rUEsMNG$<(u8kFOM#ZZ;DT3ALM4XJHn7afxF<X6NV4iZTjl2m^HotGtQ

literal 0
HcmV?d00001

diff --git a/031602408/wordCount/bin/lib/java/Store.class b/031602408/bin/lib/Store.class
similarity index 62%
rename from 031602408/wordCount/bin/lib/java/Store.class
rename to 031602408/bin/lib/Store.class
index 9c61077ef908058ae2fe64829c109d4ea8a2609d..c42b71d0ab5dff16defb6ac2b1eb494d3e70d3d4 100644
GIT binary patch
delta 339
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Rp(r8-YlsX}BBZfD`wOhyHZK4G

delta 356
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diff --git a/031602408/src/Main.class b/031602408/src/Main.class
new file mode 100644
index 0000000000000000000000000000000000000000..e793eb567bc9f23db7f318aa3c56bf11ac1ff608
GIT binary patch
literal 2461
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literal 0
HcmV?d00001

diff --git a/031602408/wordCount/src/main/java/WordCount.java b/031602408/src/Main.java
similarity index 80%
rename from 031602408/wordCount/src/main/java/WordCount.java
rename to 031602408/src/Main.java
index 039fb40..3d087c4 100644
--- a/031602408/wordCount/src/main/java/WordCount.java
+++ b/031602408/src/Main.java
@@ -1,7 +1,6 @@
-package main.java;
-
 import java.io.BufferedReader;
 import java.io.CharArrayWriter;
+import java.io.File;
 import java.io.FileReader;
 import java.io.FileWriter;
 import java.io.Reader;
@@ -9,16 +8,16 @@
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
-import java.util.Scanner;
 import java.util.TreeMap;
-import lib.java.Store;
-public class WordCount { 
+
+import lib.Store;
+public class Main{ 
 	  public static void main(String[] args) throws Exception {  
 	    	try {
-		     //File file = new File(args[0]);
-	    	//String pathname = file.getPath();
-	    	Scanner scanner=new Scanner(System.in);
-	    	String pathname=scanner.nextLine();
+	    		File file = new File(args[0]);
+	        	String pathname = file.getPath();
+//	    	Scanner scanner=new Scanner(System.in);
+//	    	String pathname=scanner.nextLine();
 	    	Reader myReader = new FileReader(pathname);
 	    	Reader myBufferedReader = new BufferedReader(myReader);  	 	
 	    	//¶ÔÎı¾´¦Àí
@@ -54,15 +53,17 @@ public static void main(String[] args) throws Exception {
 	            for (String word : wordsArr1) {  
 	                if(word.length() != 0){  //È¥³ý³¤¶ÈΪ0µÄÐÐ
 	                	
-	                	while(!(word.charAt(0)>=97&&word.charAt(0)<=122))
+	                	/*while(!(word.charAt(0)>=97&&word.charAt(0)<=122))
 	                	{
 	                		word = word.substring(1, word.length());
-	                	}
-	                	if(word.length()>=4) wordcount++;
+	                	}*/
+	                	if((word.length()>=4)&&(Character.isLetter(word.charAt(0))&&Character.isLetter(word.charAt(1))&&Character.isLetter(word.charAt(2))&&Character.isLetter(word.charAt(3)))) 	
+	                	{ wordcount++;
 	                    lists.add(word);  
 	                }  
 	            }  
-	        }  
+	        }
+			}
 			
 		
 	          
diff --git a/031602408/src/input.txt b/031602408/src/input.txt
new file mode 100644
index 0000000..24c0ba7
--- /dev/null
+++ b/031602408/src/input.txt
@@ -0,0 +1,7 @@
+aaa
+123bbb
+abc123
+dddd
+dddd
+abc123
+abc123
\ No newline at end of file
diff --git a/031602408/src/lib/Store$1.class b/031602408/src/lib/Store$1.class
new file mode 100644
index 0000000000000000000000000000000000000000..e6ad0245e50c483c7d66204a9cf3b2362f0120cc
GIT binary patch
literal 974
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diff --git a/031602408/src/lib/Store.class b/031602408/src/lib/Store.class
new file mode 100644
index 0000000000000000000000000000000000000000..2605f76087409f3eda87bf3ac594e349e786a646
GIT binary patch
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literal 0
HcmV?d00001

diff --git a/031602408/wordCount/src/lib/java/Store.java b/031602408/src/lib/Store.java
similarity index 90%
rename from 031602408/wordCount/src/lib/java/Store.java
rename to 031602408/src/lib/Store.java
index 0f8b90b..e30097f 100644
--- a/031602408/wordCount/src/lib/java/Store.java
+++ b/031602408/src/lib/Store.java
@@ -1,4 +1,5 @@
-package lib.java;
+package lib;
+
 import java.io.BufferedWriter;
 import java.io.File;
 import java.io.FileWriter;
@@ -19,9 +20,9 @@ public int compare(Entry<String, Integer> o1, Entry<String, Integer> o2) {
 		         }); 
 		          try {
 			      //System.out.println(wordcount);
-		          File file = new File("src//result.txt");
+		          File file = new File("result.txt");
 		          BufferedWriter bi = new BufferedWriter(new FileWriter(file));
-		          bi.write("characters: "+(characterscount+wordline)+"\r\n");
+		          bi.write("characters: "+(characterscount+wordline-1)+"\r\n");
 		          bi.write("words: "+wordcount+"\r\n");
 		          bi.write("lines: "+wordline+"\r\n");
 		            int k=0;
diff --git a/031602408/src/result.txt b/031602408/src/result.txt
new file mode 100644
index 0000000..a954ce7
--- /dev/null
+++ b/031602408/src/result.txt
@@ -0,0 +1,4 @@
+characters: 41
+words: 2
+lines: 7
+<dddd>: 2
diff --git a/031602408/wordCount/bin/input.txt b/031602408/wordCount/bin/input.txt
deleted file mode 100644
index b4c24b9..0000000
--- a/031602408/wordCount/bin/input.txt
+++ /dev/null
@@ -1,10 +0,0 @@
-a
-a
-a
-abcd
-abcd1234
-abcd
- abcd
-file
-file
-123file
\ No newline at end of file
diff --git a/031602408/wordCount/bin/lib/java/Store$1.class b/031602408/wordCount/bin/lib/java/Store$1.class
deleted file mode 100644
index dfd9dd618bae2623e1aa6193b68927b63c26750f..0000000000000000000000000000000000000000
GIT binary patch
literal 0
HcmV?d00001

literal 1251
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diff --git a/031602408/wordCount/bin/main/java/WordCount.class b/031602408/wordCount/bin/main/java/WordCount.class
deleted file mode 100644
index 16fe6a7951a080614a990a8ea499e6ef5b094c03..0000000000000000000000000000000000000000
GIT binary patch
literal 0
HcmV?d00001

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diff --git a/031602408/wordCount/src/input.txt b/031602408/wordCount/src/input.txt
deleted file mode 100644
index b4c24b9..0000000
--- a/031602408/wordCount/src/input.txt
+++ /dev/null
@@ -1,10 +0,0 @@
-a
-a
-a
-abcd
-abcd1234
-abcd
- abcd
-file
-file
-123file
\ No newline at end of file
diff --git a/031602408/wordCount/src/main/java/wordCount.txt b/031602408/wordCount/src/main/java/wordCount.txt
deleted file mode 100644
index b4c24b9..0000000
--- a/031602408/wordCount/src/main/java/wordCount.txt
+++ /dev/null
@@ -1,10 +0,0 @@
-a
-a
-a
-abcd
-abcd1234
-abcd
- abcd
-file
-file
-123file
\ No newline at end of file
diff --git a/031602408/wordCount/src/result.txt b/031602408/wordCount/src/result.txt
deleted file mode 100644
index 3eea6de..0000000
--- a/031602408/wordCount/src/result.txt
+++ /dev/null
@@ -1,6 +0,0 @@
-characters: 49
-words: 7
-lines: 10
-<abcd>: 3
-<file>: 3
-<abcd1234>: 1