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WASHINGTON, July 7 (Xinhua) -- Space shuttle Atlantis will soar into the sky Friday on NASA's 135th and final flight. Its scheduled return to Earth later this month will mark the end of NASA's 30-year space program.Since its onset with the launch of space shuttle Columbia, the program has been seen as a cheap, safe and reliable way for space exploration.Despite its great contributions to U.S. manned space flight, it has also left some grave and tragic lessons, making its termination inevitable.HIKING COSTSLaunched in 1972 by then President Richard Nixon, the shuttle program aimed to provide a new system of affordable space travel and proved to be NASA's most enduring project in its 50 years of existence.In 1981, shuttle Columbia made its first shuttle flight for two days. It was the ultimate hybrid and the first reusable spacecraft.Launched like a rocket and gliding back to Earth like an airplane, space shuttles not only can act as a space taxi to carry astronauts, but have the muscle of a long-distance trucker to haul heavy machinery.The spaceship boasts more than 3,500 subsystems and 2.5 million parts and is nine times faster than a speeding bullet as it climbs heavenward. That versatility, however, has translated into higher costs.NASA originally estimated the program would cost about 90 billion U.S. dollars. However, its actual cost stands at about 200 billion dollars, compared with the 151 billion dollars spent on Apollo which took Americans to the moon in 1969.In an article in Technology Review, John Logsdon, former head of the Space Policy Institute at George Washington University, drew a direct connection between the ravenous shuttle budget and the lack of other large advances in manned space flight."By operating the system for 30 years, with its high costs and high risk, rather than replacing it with a less expensive, less risky second-generation system, NASA compounded the original mistake of developing the most ambitious version of the vehicle," he wrote."The shuttle's cost has been an obstacle to NASA starting other major projects," he added.HIGH RISKIn terms of safety, the shuttles have never been as reliable as their designers had envisioned.On average, one out of every 67 flights ended up with fatal accidents. Based on the rate of deaths per million miles traveled, the space shuttle is 138 times riskier than a passenger jet.Seven astronauts onboard died when Challenger exploded about a minute after launch in 1986. Nearly two decades after the tragic blast, a new catastrophe descended when the shuttle Columbia disintegrated moments before landing in 2003, killing another seven spacemen.Again, the shuttle program was shelved for more than two years as NASA stepped up efforts to make it safer. But experts say the fundamental problem related to shuttles' safety cannot be solved due to their "birth defects.""It is in the nation's interest to replace the Shuttle as soon as possible," concluded the panel that investigated the 2003 Columbia accident.

BEIJING, June 3 (Xinhua) -- Google lacked evidence to support its accusations that Chinese hackers are behind the alleged cyber attacks on hundreds of its email accounts and the timing to make such accusations is evil-intentioned, Chinese experts said on Friday."Google's accusation is neither serious nor credible as it has not published any evidence that shows the hackers are from China," said Dai Yiqi, a cyber security expert with Tsinghua University.Eric Grosse, engineering director of Google's Security Team wrote on the company blog Wednesday that unidentified hacker attacks likely originated from the eastern Chinese city of Jinan, tried to collect user passwords of the Gmail accounts of hundreds of users, including senior U.S. government officials, Chinese "human rights activists" and journalists.A report released in 2009 by the United States-China Economic and Security Review Commission, an organization created by the U.S. Congress, claimed that Jinan is the home of a Chinese military reconnaissance office.An anonymous cyber security expert believes, despite Google not referring to the Chinese government in the latest attack claim, the company is targeting the Chinese government by listing the victims of the attacks as those whom only the Chinese government are interested in."Both their intentions and the timing of the accusation are dubious," Dai said.Google's accusation followed on the heel of the reported Pentagon's first formal cyber strategy. The Wall Street Journal reported Tuesday that the Pentagon concluded that computer sabotage coming from another country can count as an act of war and the United States may respond by using traditional military force.Li Shuisheng, a research fellow with a top military science academy of the People's Liberation Army, believes there are political motives behind Google's accusation.Google may well have attempted to instigate a new round of the cyber row between China and the United States, Li said.Wednesday's accusation by Google came more than a year after the company allegedly uncovered a cyber attack on its systems that it said it traced to China.In January, 2010, Google said it had been attacked by hackers supported by the Chinese government, and later announced to withdraw from Chinese mainland. The row ended up with Google redirecting Chinese mainland users to a site in Hong Kong.In such cyber attacks, it is easy to locate the IP address of hackers but hard to tell where the hackers actually are, said Dai."Hackers usually launch attacks by camouflaging their own IP addresses or controlling computers of others. Therefore, we can hardly tell the location of the hacker unless we have sufficient evidence," he said.China is one of the leading targets of cyber attacks. It has the world's largest number of computers infected with bot, a type of malware which allows a cyber attacker to gain control over the affected computer.About 13 percent of the world's computers infected with bot are in China."Without cooperation between governments, absolute security cannot be guaranteed in cyber community," said Li , adding only cooperation can ensure safe information exchange.

WASHINGTON, June 8 (Xinhua) -- Hundreds of small genetic variations are associated with autism spectrum disorders, including an area of DNA that may be a key to understanding why humans are social animals, according to a multi-site collaborative study led by researchers at Yale University.To be published Thursday in the journal Neuron, the study reinforces the theory that autism, a disorder that develops in early childhood involving impairments in social interaction, language deficits and distinctive behaviors, is not caused by one or two major genetic defects, but by many small variations, each associated with a small percentage of cases.The study looked at more than 1,000 families in which there was a single child with an autism spectrum disorder, an unaffected sibling and unaffected parents. The team compared individuals with autism to their siblings to determine what types of genetic changes distinguished the affected child from the unaffected child.One of the most intriguing of these findings points to the same small section of the genome that causes Williams syndrome -- a developmental disorder marked by high sociability and an unusual aptitude for music.In autism, there is an increase in the chromosomal material, an extra copy of this region, and in Williams syndrome, there's a loss of that same material," said lead author Matthew State. "What makes this observation particularly interesting is that Williams syndrome is known for a personality type that is highly empathetic, social, and sensitive to the emotional state of others. Individuals with autism often have difficulties in the opposite direction. This suggests that there is an important key in that region to understanding the nature of the social brain."State and his team also found about 30 other regions in the genome that are very likely contributing to autism and are focused on about six of those regions that showed the strongest evidence."We're now moving on to a second phase of the study looking at an additional 1,600 families and should be able to identify multiple new regions that are strongly implicated in autism," he said.

SAN FRANCISCO, June 20 (Xinhua) -- Google and the British Library announced Monday that the Internet search giant will digitize 250,000 out-of-copyright books from the library's collections, making up to 40 million pages from 1700 to 1870 available to the public online.In a joint statement, the British Library and Google said they will work in partnership over the coming years to deliver the content free through Google Books and the library's website, and full text search, download and reading will be available. Google will cover all digitization costs.The project is going to cover a huge range of printed books, pamphlets and periodicals dated 1700 to 1870, a period of political and technological turmoil, from the Industrial Revolution to the French Revolution, from the introduction of the income tax in Britain and the invention of the telegraph and railway.It will include material in a variety of major European languages and will focus on books that are not yet freely available in digital form online, said the statement.Since December 2004, Google has announced partnership with some 40 high-profile university and public libraries, planning to digitize and make available some 15 million volumes within a decade through Google Books service.The project has triggered controversy as publisher and author associations oppose the plan to put copyrighted titles online in a class action lawsuit.

CANBERRA, Sept. 1 (Xinhua) -- Bushranger Ned Kelly's headless body has finally been identified in Australia, more than 130 years after his execution in the Old Melbourne Gaol, Victoria's Attorney- General Robert Clark announced on Thursday.Clark said the bushranger's remains have been identified by doctors and scientists at the Victorian Institute of Forensic Medicine (VIFM).Kelly was an Irish Australian bushranger, considered by some merely a cold-blooded killer, while by others a folk hero and symbol of Irish Australian resistance against oppression by the British ruling class for his defiance of the colonial authorities. He was hanged for murder in 1880 at Old Melbourne Gaol. His daring and notoriety made him an iconic figure in Australian history, folklore, literature, art and film.The project involved collaboration with the ancient DNA laboratory EAAF in Argentina, which has worked with the VIFM on other forensic projects.Clark said "This is an extraordinary achievement by our forensic team here in Victoria," he told reporters in Melbourne on Thursday."To think a group of scientists could identify the body of a man who was executed more than 130 years ago, moved and buried in a haphazard fashion among 33 other prisoners, most of whom are not identified, is amazing." The investigation started when a skull believed to belong to Kelly was handed to the VIFM on Nov. 11, 2009.The skull handed in in 2009 was found not to be that of Ned Kelly, and Glenrowan historian Gary Deans said the next step is to find Kelly's skull."The Government should put a request in the public arena for the return of Ned Kelly's skull," he told ABC News."We know thanks to Jack Cranston, who held the skull around 1929, that it was sitting on a detective's desk. This was around the same time that remains were dug up in the Old Melbourne Gaol."I imagine that that detective or somebody else took it home."