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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, Aug. 16 (Xinhuanet) -- Almost one in four Chinese students aged between 12 and 14 have tried smoking, according to the results of a survey released by the Chinese Association on Tobacco Control (CATC).The survey, carried out among 38,839 students and 6,503 teachers from middle and high schools in 11 provinces across the country between May and June, showed that 22.5 percent of students aged between 12 and 14 had tried smoking and that 15.8 percent of middle and high school students smoke regularly."There are definitely quite a number of boy students in my class who smoke regularly as some have been found smoking outside campus during lunch break," said Li Xiaolan, an English teacher from a high school in Shanghai. The survey also found that 39 percent of students took their first cigarette from their classmates."It was quite common to smoke with my classmates at school and we usually smoked in toilets or in corners of the playground after lunch," said Zhou Guangrong, a 22-year-old university student from Guiyang, Guizhou province, who started smoking when he was 12.The majority of student smokers buy cigarettes themselves and about 76 percent of the adolescent smokers said that there is at least one cigarette shop within 200 meters from their school."When I was a student at middle and high schools, they were surrounded by cigarette shops," said Zhou who used to smoke two cigarettes per day in primary school and two packs per week in middle and high school."We're keen to show that more adolescents are starting smoking much younger than before, and that we need to minimize the number of young smokers," said Duan Jiali, secretary-general of the youth tobacco control commission under CATC. Duan added that teachers and parents should set a good example for teenagers by not smoking in front of them at school or at home, which is the most influential way of stopping adolescents from smoking.China banned smoking in 16 types of public indoor venues - including hospitals, schools, bars, restaurants and hotels - on May 1 in an attempt to curb tobacco use in the country with the world's largest number of smokers.Currently, there are more than 300 million smokers in China, and about 1.2 million people die from smoking-related diseases every year, accounting for one-fifth of the world's total, according to statistics from the World Health Organization."Meanwhile, about 540 million people are exposed to secondhand smoke, 48.9 percent of which are adolescents (from 15 to 19 years old)," said Xu Guihua, deputy director of the CATC."It's essential and urgent for us to control the number of adult smokers who potentially tempt adolescents to smoke."

BRUSSELS, May 31 (Xinhua) -- Baby bottles containing the substance Bisphenol A (BPA) would have to be pulled from the shelves across the European Union (EU) starting from Wednesday, in a "milestone" move to better protect the health of EU citizens, an official said Tuesday."Due to the fact that there are uncertainties concerning the effect of the exposure of infants to Bisphenol A, the commission deemed it both necessary and appropriate to take action," said John Dalli, EU Health and Consumer Policy Commissioner."The aim is to further reduce the exposure of the most vulnerable part of our population, i.e. infants," he said.The ban, adopted in an EU directive in late January, would prohibit baby bottles containing BPA from placing on the EU market and import into the 27-member EU from June 1.Previously, the bloc had already banned the manufacture of the controversial baby bottles on March 1, and the industry has been withdrawing such products voluntarily.BPA is an organic molecule that is used in the manufacture of polycarbonate plastics, which are used to manufacture plastic materials, such as baby bottles.Traces of BPA can be released from plastic containers into the food they carry if these containers are heated at high temperatures. They may lead to early sexual development of children and could cause cancer, according to health officials.China would also prohibit the manufacture of feeding bottles containing BPA from June 1, while imports and sales of bottles containing BPA would be banned starting from Sept. 1.

SAN FRANCISCO, Sept. 13 (Xinhua) -- Microsoft released on Tuesday a test version of Windows 8 to developers, posing to regain ground of the tablet market dominated by Apple and Google.At its developer-focused BUILD conference held in Anaheim, California, the software giant handed out new Samsung tablet computers with a test version of the code-named "Windows 8," the first detailed preview of the system for developers and people outside Microsoft.Generally expected to be launched in fall 2012, Microsoft did not say when the system will ship or its price.Microsoft Windows President Steven Sinofsky introduces the new tablet running a test version of its touch-enabled Windows 8 at the Build conference in Anaheim, California September 13, 2011Featuring a home page filled with colorful application tiles, the new system boots up in seconds. Microsoft said the system will run on low-power ARM-based chips that power smartphones and tablets. Windows 8 also introduces a new "Metro style" interface, which run full-screen and users can multitask in two at a time."We reimagined Windows," said Steven Sinofsky, president of the Windows and Windows Live Division at Microsoft, in his keynote address to the thousands of developers in attendance. "From the chipset to the user experience, Windows 8 brings a new range of capabilities without compromise."Analysts said the new system is consumer-oriented and intuitive but it will take time to see whether it is an "iPad killer."As professionals and consumers began to spend more time on smartphones and tablets, Microsoft has not got a significant bite of the market, losing ground to Apple's iPad and devices running Google's Android system.

BEIJING, Sept. 4 (Xinhua) -- Officials and delegations from China and African countries have gathered at a seminar being held in Beijing to discuss rural development and economic growth.The seven-day seminar kicked off on Sunday, attracting representatives from China and 11 African countries to exchange views and experiences related to the seminar's theme of "agriculture and rural development."Justin Lin Yifu, chief economist and senior vice president of the World Bank, said at the seminar's opening ceremony that African countries should take cues from China's experience in creating a series of policies to bolster agricultural and rural development, as these policies have also facilitated the country's economic growth.Hu Jinglin, assistant to China's Minister of Finance, said improved agricultural cooperation between China and Africa will help enhance global grain security.China has worked on 142 cooperative agricultural projects with 14 African countries to date. In addition, it has sent 104 agricultural experts to 33 African countries to train more than 4,200 local agricultural technicians.

来源：资阳报