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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.

CANBERRA, Sept. 6 (Xinhua) -- A rare virus that can be contracted by humans has killed a large number of Victorian pigeons after being detected in the Australian state for the first time, Agriculture Department confirmed on Tuesday.According to the Australian Chief Veterinary Officer, Dr Mark Schipp, the avian paramyxo virus has already started killing some hobby birds, and threatens to spread to Victoria's chicken population.He said the affected birds have died suddenly in large numbers and have sometimes appeared tired or have shown neurological signs such as circling or head flicking before death.He added that the bug can also cause conjunctivitis or influenza-like symptoms in humans."The virus causes only mild, short-term conjunctivitis or influenza-like symptoms (in humans)," Australia Associated Press quoted Schipp as reporting on Tuesday."Human infection with this virus is extremely rare and usually occurs only in people who have close direct contact with infected birds."At this stage, there are no reports of the virus causing disease in wild birds, but the Australian Wildlife Health Network has been asked to monitor the situation.

WASHINGTON, Sept. 27 (Xinhua) -- At least 13 people had been killed amid 72 sickened in 18 states in listeria outbreak traced to Colorado cantaloupes, making it the most deadly U.S. outbreak of food-borne infection since 1998, the Centers for Disease Control and Prevention (CDC) said Tuesday in a statement posted on its website.Of the 13 deaths, four were in New Mexico, two were in Colorado, two were in Texas, and there was one each in Kansas, Maryland, Missouri, Nebraska and Oklahoma.Victims range in age from 35 to 96 years, with an average age of 78. All of the illnesses started on or after July 31.The figures were the latest confirmed as of Monday morning, according to the CDC. But they may well rise in the still-widening outbreak as state and local officials are investigating three additional deaths that may be connected.In 1998, 21 people died from listeria linked to tainted hot dogs, according to a CDC online database.The Food and Drug Administration on Sept. 14 warned consumers not to eat cantaloupes from Colorado's Rocky Ford region shipped by Jensen Farms. The cantaloupes with the brand name Rocky Ford were distributed from July 29 to Sept. 10 in at least 17 states.Listeria is a common bacterium that typically causes mild illness in healthy people, but can cause severe illness in older people and those with compromised immune systems. It also can cause miscarriages and stillbirths in pregnant women and severe infections in new babies.Listeria infections lead to about 1,600 serious illnesses each year and about 260 people die, according to the CDC.The CDC estimates that about 48 million people in the U.S. each year get sick from tainted food, with about 128,000 hospitalized and 3,000 deaths.

BEIJING, Aug. 31 (Xinhuanet) – The pressure of modern society is taking a toll on sexual satisfaction, experts say following the release of an online survey.About 34 percent of people polled in the survey said that they are unsatisfied with their sex lives, with 6.5 percent "very unsatisfied".Another 32 percent condemned their sex lives as "just so-so".The survey interviewed more than 3,000 people, aged between 15 and 55, with men accounting for 74 percent of the interviewees.It was conducted by the China Population Communication Center and the Shanghai Academy of Social Sciences from May 1 to June 20. The survey did not give a margin of error.Only 23 percent of respondents said that they are "satisfied" with their sex lives, with 3.6 percent "very satisfied", according to the survey.But women seem to have a higher rate of satisfaction than men, with only 26 percent saying they are unsatisfied. The rate for men is 42 percent.The rate of sexual satisfaction among Chinese people is below the global average of 44 percent, according to an earlier survey by Durex. The 2007 Durex Global Sexual Wellbeing Survey questioned more than 26,000 people in 26 countries about all aspects of their sex lives - including satisfaction levels.Jiang Hui, president-elect of the Chinese Society of Andrology, attributed the lower rate of sexual satisfaction among Chinese people to rapid economic growth, which inevitably increases work and social pressure.Health problems associated with a modern lifestyle, such as diabetes and hypertension, are also to blame, he said.Jiang said his department of andrology used to receive about 10 patients a day 10 years ago. Now the figure has risen to more than 250.Rising awareness of sex and a more open attitude toward the once-taboo topic among the public also contributed to higher sexual expectations, he said.The survey also revealed that about 30 percent of respondents in the 35-55 age group had sex less than once a week."That rate is quite low, compared with the global average of 103 times a year, or 1.98 times a week," said Yang Xiong, who heads the social survey center at the Shanghai Academy of Social Sciences.Only 16.9 percent of respondents said that they had sex more than 10 times a month. Most respondents had sex three to nine times every month.About 8 percent of respondents said that they basically had no sex at all or it was too infrequent to be classified.The survey seemed to find that the more you made, the less you had. Those who earned at least 9,000 yuan (,400) a month had less sex than those who earned less, according to the survey.Among those making more than 9,000 yuan per month, over 70 percent said they had sex less than twice a month, compared with 16.5 percent for those with a monthly salary of less than 6,000 yuan.The survey also found that when people run into problems with their sex lives, 83 percent turn to the Internet, rather than professionals, for help. Less than 6 percent said they would see doctors to solve sex-related problems.Nearly 70 percent of those polled said they suffered from sexual health problems, such as erectile dysfunction (ED)."Many patients, especially men, are reluctant to see a doctor, which they think harms their manhood," Jiang said.According to a study conducted by the Chinese Society of Andrology, at least 40 percent of men aged 40 and above suffered from erectile dysfunction, roughly the global average.But Yang, from the Shanghai academy, noted that surveys conducted online tend to produce far different results than those conducted face-to-face.He expressed reservations about the survey's accuracy and said the public should only use the results for reference.

BEIJING, Sept. 10 (Xinhua) -- China will start "overall and thorough" safety checks on offshore oil exploration and production to eliminate risks in the wake of oil spills in the country's northern Bohai Bay, the work safety authority said Saturday.The checks, which starts from September 10 to December 10, will be applied to all offshore oil exploration and production, the State Administration of Work Safety said in a circular addressed to oil companies on its website.The companies include China National Petroleum Corporation, China Petrochemical Corporation, China National Offshore Oil Corporation, ConocoPhillips China, Kerr-McGee China Petroleum Ltd., Roc Oil (Bohai) Company, CACT Operators Group, Husky Oil China Ltd., Shanghai Petroleum Co., Energy Development Corporation (EDC) China and Tincy Group Energy, the statement said.The administration urged these enterprises to conduct self-examinations on their offshore fixed and mobile platforms and floating production storage and offloading units, submarine pipelines and onshore oil terminals in two months till November 10. They should file result reports before November 20.The authority's officials, joined by experts, will launch inspections from late November, the statement said. The checks cover well control amid drilling operation, safety management during production, facilities, and management over extreme weather, it added.The order came after the State Council on Wednesday called for strengthened monitoring and management of the marine environment as well as safety checks over the country's ocean oil fields to toughen safety measures and erase potential risks.The decision was made after oil spills at an offshore oil field run by U.S. oil giant ConocoPhillips have polluted more than 5,500 square km of sea water in the Bohai Bay since June.The central government also imposed restricts on new petrochemical projects and ban reclamation projects in the bay for environmental concerns.China has stepped up efforts to explore and materialize offshore resources to seek more dependence of the marine industries as a strategic development move. In its 12th Five-Year Plan, the government advocates greater scientific and systematic utilization of marine resources and coastal areas as energy demand soars.