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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.

BEIJING, Aug. 5 (Xinhuanet) -- A study conducted by Israeli researchers at the Albert Einstein College of Medicine in New York shows that genes, rather than good eating and lifestyle habits, determine longevity, according to media reports Friday. "This study suggests that centenarians may possess additional longevity genes that help to buffer them against the harmful effects of an unhealthy lifestyle," said senior author Nir Barzilai, director of the Institute for Aging Research at Yeshiva University's Albert Einstein College of Medicine.The study involves 477 Ashkenazi Jews between the ages of 95 and 122, of whom 75 percent are women. According to the study, Ashkenazi Jews are chosen as subjects because they are more "genetically uniform than other populations, making it easier to spot gene differences that are present."The study also found that the long-lived Ashkenazi Jews drank slightly more and exercised less than their average counterparts. But Barzilai also warned: “Although this study demonstrates that centenarians can be obese, smoke and avoid exercise, those lifestyle habits are not good choices for most of us who do not have a family history of longevity.""We should watch our weight, avoid smoking and be sure to exercise, since these activities have been shown to have great health benefits for the general population, including a longer lifespan," He added.

BEIJING, Sept. 26 (Xinhuanet) -- Young unmarried migrant women are facing a high risk of induced abortions in China and experts urged that they have better access to reproductive health education.Among the 8 to 10 million induced abortions performed on the mainland each year, nearly 47 percent involve unmarried women younger than 25, according to Cheng Linan, director of the center for clinical research and training of the Shanghai Institute of Planned Parenthood Research.The statistics are based on the results from a recent nationwide survey."The rising trend of induced abortions is even more evident among migrants who usually have poor awareness and access to reproductive health knowledge and services, particularly about contraception," she said on Saturday at an event to mark World Contraceptive Day, which falls on Sept 26.A 2008 survey involving more than 50,000 induced abortions in Beijing showed that roughly 70 percent of the women undergoing the procedure were migrants. For many, it was not their first abortion.According to a nationwide study by the Chinese Medical Association (CMA), of all women having received induced abortions, nearly 56 percent had two operations and 13.5 percent had three or more."That not only causes the women certain physical or mental problems, but it also gives the country a huge economic burden of more than 3 billion yuan" or about 0 million, she said.Among Chinese women who became infertile, more than 88 percent previously had an induced abortion, a study conducted in 2007 showed.Other potential health hazards include hemorrhage, uterine or pelvic infection, uterine perforation and cervical laceration.Apart from low awareness, poor access to professional consultations on contraception, particularly among single young women, is mainly the problem.A 2011 survey by the CMA found that about 44 percent of those polled said they had difficulty accessing scientifically correct contraceptive information, compared with a global average of 15.5 percent.

SAN FRANCISCO, Aug. 17 (Xinhua) -- Microsoft's cloud-based software Microsoft Office 365 on Wednesday experienced its first major outage since its introduction in late June."At approximately 11:30 a.m. PDT, Microsoft became aware of a networking issue affecting customers of some Microsoft services hosted out of one of our North American data centers," said Steven Gerri, general manager for Microsoft Global Foundation Services, in a statement"We apologize for the inconvenience that Office 365 outage has caused today. We are working on resolving the issue," the software giant said via Twitter.Outages were reported in Chicago, Denver and New York City among other locations. According to tweets from affected users, they were unable to access their email and managers were unable to manage accounts.The outage lasted approximately five hours and services have been restored for the moment.According to Microsoft service-level agreement, Microsoft guarantees a 99.9 percent level of uptime. If it fails to reach 99.9 percent uptime, users are eligible for 25 percent service credit.As more industry giants try to entice users to move to the "cloud," a term refers to the management and provision of applications and data over the Internet, the downtime again reminds cloud computing users that they must prepare to deal with outages and rethink their dependency on the service, analysts said.Amazon has suffered two major cloud outages earlier this month and back in April, impacting some of its high-profile users like movie streaming service Netflix and location-based social networking Foursquare.Analysts recommend cloud users to store data with multiple service providers to minimize the risk and limit their dependency on cloud services for business-critical processes.Available in 40 countries and regions since June 28, Office 365, which Microsoft CEO Steve Ballmer said is "where Microsoft office meets the cloud," combines Microsoft Office, SharePoint Online, Exchange Online and Lync Online into a single cloud-based package for business users.

XICHANG, Sichuan, Aug. 12 (Xinhua) -- China launched a communications satellite PAKSAT-1R for Pakistan at 0:15 a.m. Friday from the Xichang Satellite Launch Center in southwest China's Sichuan Province.The satellite was carried by a Long March-3B carrier rocket, according to the launch center. It is China's first in-orbit delivery to Asian customers and also the first commercial satellite export to international users this year.According to statistics from the control center, the satellite successfully separated from its carrier rocket and entered geostationary transfer orbit as scheduled, 26 minutes after being launched.PAKSAT-1R will provide a range of services, including broadband Internet, telecom and broadcasting, covering some regions of Europe, South Asia, the Middle East, and the eastern Africa.The contract for the PAKSAT-1R was signed in 2008 between China Great Wall Industry Corporation and the Space and Upper Atmosphere Research Commission of Pakistan.China and Pakistan share a long history of space technology cooperation. Pakistan's first low-orbit satellite, BADR-A, was launched by China in 1990 with Long March 2E rocket.

来源：资阳报