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CANBERRA, Aug. 17 (Xinhua) -- Australian scientist on Wednesday said his international research team has discovered the trick on how butterfly learn to change its wing pattern to avoid being eaten by birds.The Amazonian butterfly, Heliconius numata, has learnt to carry out a single genetic switch to alter its wing pattern so it appears to be another bad-tasting butterfly that birds will avoid.Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at Australia's University of Melbourne was part of the international research team, which was led by scientists at Centre National de la Recherche Scientifique (CNRS) and the University of Exeter in United Kingdom.Dr. Lee said the historical mystery had puzzled researchers for decades."Charles Darwin was puzzled by how butterflies evolved such similar patterns of warning coloration," Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at the University of Melbourne told Western Australia Today."We have now solved this mystery, identifying the region of chromosome responsible for changing wing pattern."He said the research team identified a genetic switch known as a supergene, which allowed the butterfly to morph into several different forms, allowing one species to mimic another."It is amazing that by changing just one small region of the chromosomes, the butterfly is able to fool its predators by mimicking a range of different butterflies that taste bad," he said."The butterflies rearrange this supergene DNA like a small pack of cards, and the result is new wing patterns. It means that butterflies look completely different but have the same DNA."There are other butterflies doing similar tricks, but this is the most elegant one."I was just fascinated by how elegant they were."He said the discovery proves that small chromosomal changes can preserve successful gene combinations, and thus help a species to adapt.The findings of the study are published on August 14 in the international journal Nature.

WASHINGTON, June 14 (Xinhua) -- Short sleep duration may contribute to the development or worsening of hyperactivity and inattention during early childhood, suggests a research abstract that was presented Tuesday at SLEEP 2011, the 25th Anniversary Meeting of the Associated Professional Sleep Societies LLC.Results show that less sleep in preschool-age children significantly predicted worse parent-reported hyperactivity and inattention at kindergarten. The sample consisted of approximately 6,860 children, and analyses controlled for gender, ethnicity and family income."Children who were reported to sleep less in preschool were rated by their parents as more hyperactive and less attentive compared to their peers at kindergarten," said lead author Erika Gaylor, senior researcher for SRI International, an independent, nonprofit research institute in Menlo Park, California. "These findings suggest that some children who are not getting adequate sleep may be at risk for developing behavioral problems manifested by hyperactivity, impulsivity, and problems sitting still and paying attention." According to the authors, attention-deficit/hyperactivity disorder (ADHD) is not generally diagnosed until the school-age years. However, the onset of developmentally inappropriate inattention, hyperactivity and impulsivity is often much younger. Sleep problems, particularly difficulty falling asleep and staying asleep, are frequently reported in children and adolescents with ADHD. However, the direction of causation, if any, has been difficult to determine. Longitudinal studies may provide a window into the direction of this complex relationship.Last year at SLEEP 2010, Gaylor reported that having a regular bedtime was the most consistent predictor of positive developmental outcomes at four years of age. Having an earlier bedtime also was predictive of higher scores for most developmental measures.

LONDON, Sept. 22 (Xinhua) -- A British publisher on Thursday issued an "unauthorized autobiography" of the founder of the controversial Wikileaks website Julian Assange.Assange became a global figure after he published 250,000 secret United States diplomatic cables on his Wikileaks website, which became a serious embarrassment to the American government.He was then accused by two women of rape when he was in Sweden. Swedish police said they wanted to question him, and issued a European Arrest Warrant in 2010 for him.Assange, 40, denies the allegations and surrendered himself to police in London at the end of 2010, and the Swedish authorities applied for his extradition to face questioning.Assange fought the extradition bid in the English courts, fearing that he could face further extradition from Sweden to the United States where he could face criminal charges related to the publishing of the secret cables, but failed.He appealed against the extradition ruling in July and a final decision on the case will be made by senior English judges, probably before Christmas.Assange agreed to cooperate with Edinburgh-based publisher Canongate in publishing an autobiography and had 50 hours of interviews with a ghostwriter between January and March this year, while he was on bail awaiting an outcome of the extradition hearings.He received a 500,000 pound advance (about 768,000 U.S. dollars) for the book.Publisher's spokesman Liz Sich told Xinhua Thursday, "It's an unauthorized autobiography -- it is his words. He was contracted to write his autobiography in December; a ghostwriter was assigned to it, approved by the publisher and Julian and an intense amount of work was done in the first three months of 2011. The first draft was delivered on schedule at the end of March. After that there was an hiatus and nothing happened; in June Julian decided he wanted to tear up the contract."Assange has opposed publication, but Sich said, "It is very much Julian's words, it is written in the first person. He didn't want it to be published but he was in breach of his contract. He couldn't pay the advance back because he had used it to pay his lawyers."The book is available only in English at the moment, but a Dutch publisher and a Turkish publisher said they would print translations in their languages, and other foreign language editions are also likely.

BERLIN, June 5 (Xinhua) -- German authority said on Sunday that bean sprouts might be the "most convincing" source for the E. coli outbreak which has killed 22 people and infected more than 2,000 in the Europe.Gert Lindemann, Agriculture Minister of the state Lower Saxony, told reporters in a press conference that restaurants and food outlets where the cases of E. coli had been reported all had received shipments of the particular bean sprouts.A related company in the Uelzen region has been shut down and its products have been recalled, he said."It is the most convincing... source for the E. coli outbreak," Lindemann said. Although a conclusive laboratory analysis will not come out until Monday, current indications were strong enough to issue a public warning, he said.Authorities have been racing to track down the source of the pathogen since the outbreak, which has infected people in 12 countries - all of whom had once traveled in northern Germany. More than 600 of those infected have developed Hemolytic Uremic Syndrome (HUS), a potentially deadly complication attacking the kidneys.The source of E.coli was first thought to be the cucumbers from Spain, which has caused huge loses for Spain farmers. However, this conclusion was overthrown by Laboratory tests in Hamburg on Tuesday.

CANBERRA, Aug. 31 (Xinhua) -- Australia's new chief medical officer, Professor Chris Baggoley, on Wednesday said Australian should not be worried about reports that a mutant strain of the deadly bird flu virus is spreading across Asia and beyond.On Monday, the UN's Food and Agriculture Organization (FAO) said a mutant strain of the deadly avian influenza virus was spreading in Asia and issued a warning that the bird flu could spread from poultry to humans. It urged "heightened readiness and surveillance" as the mutant strain posed "unpredictable risks to human health."But Professor Baggoley, who took office on Tuesday, said Australia is well served by strict testing and customs regimes, adding that avian migration patterns also mean infected birds are highly unlikely to arrive in Australia."I don't think we should be worried," Prof Baggoley told Sky News."The country and the Australian government is certainly vigilant in relation to bird flu."Prof. Baggoley insisted the H5N1 virus remains overwhelmingly a disease of birds and it is very uncommon for humans to catch it. It is also exceedingly rare for humans to spread it among themselves.He said that even if bird flu did arrive and affected humans, Australia is ready to respond to any new and significant developments in bird flu."Australia tests migratory wild birds, looking for H5N1, and has been doing this for some years and has never found it," he said."On the human side of things, Australia has been preparing for a possible outbreak of H5N1 since 2004."We've got the laboratory capacity to diagnose influenza; we've got arrangements in place for a rapid production of an H5N1 vaccine for humans, and we've got ready access to antivirals."There have been no outbreaks of bird flu in Australia to date.The UN said the latest human death from bird flu occurred earlier this month in Cambodia, which has registered eight cases of human infection this year, all of them fatal.H5N1 has infected 565 people since it first appeared in 2003, killing 331.

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