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JIUQUAN, Gansu, Sept. 26 (Xinhua) -- Engineers are conducting the final preparations before launching China's first space laboratory module at the end of this week at a launch center in northwest China.The unmanned Tiangong-1 module was originally scheduled to be launched into low Earth orbit between Sept. 27 and 30. However, a weather forecast showing the arrival of a cold air mass at the Jiuquan Satellite Launch Center forced the launch to be rescheduled for Sept. 29 or 30, depending on weather and other factors."This is a significant test. We've never done such a thing before," said Lu Jinrong, the launch center's chief engineer.A full ground simulation was conducted on Sunday afternoon to ensure that the module and its Long March 2F carrier rocket are prepared for the actual launch.Cui Jijun, commander-in-chief of the launch site system and director of Jiuquan Satellite Launch Center, told Xinhua that they developed a new target spacecraft for the mission and made more than 170 technical improvements to the Long March 2F, China's manned orbital carrier rocket.Engineers have also made more than 100 updates at the launch site in order to make it compatible with the Tiangong-1, Cui added.The module will conduct docking experiments after entering orbit, which is the first step in China's space station program.Cui said the launch site has an updated computer center and command monitoring system and increased ability to adapt to changes in mission conditions, as well as the resources to handle both the launch and command duties. An integrated simulation training system for space launching has also been developed for the docking mission.The mission comes just one month after the Long March 2C rocket malfunctioned and failed to send an experimental satellite into orbit. The Tiangong-1 mission was subsequently rescheduled in order to allow engineers to sort out any problems that might occur during the launch.Cui said that engineers conducted a two-month comprehensive technical check on equipment at the launch site from March to May. The safety and reliability of all the instruments have been significantly improved."[The launch site] has the full conditions to conduct the Tiangong-1 mission," said Cui.The Tiangong-1 will remain in orbit for two years. During its mission, it will dock with China's Shenzhou-8, -9 and -10 spacecrafts.Unmanned docking procedures will be an essential step toward China achieving its goal of establishing a manned space station around 2020.

LOS ANGELES, Sept. 1 (Xinhua) -- Fisker Automotive, a Southern California electric car maker, announced on Thursday that it has signed a pact with BMW regarding the supply of engines and other related components for future models in a major tieup.The Anaheim, Orange County-based U.S. car maker will get a four-cylinder turbocharged engine, totalling 100,000 units every year, for its next generation of cars under a project code-named "Project Nina," the company said.The production of the model, a mass-market plug-in hybrid sedan, will begin at the end of 2012 and the sale is slated for 2013."The BMW engine was an obvious choice for us, as BMW is known for producing the best and most fuel efficient gasoline engines in the world," Fisker's CEO and Executive Design Director Henrik Fisker said. "We are very pleased to have signed this agreement with BMW."The firm did not disclose the terms.The U.S. automaker, founded in 2007, has produced electric vehicles with extended range (EVer). The first derivative of "Project Nina" will be a mid-sized premium sedan which utilizes the technology.The company's other products include Fisker Karma Sedan, a luxury sports car and the world's first premium electric plug-in hybrid.

BEIJING, June 28 (Xinhuanet) -- A truck-sized asteroid passed over the Atlantic Ocean within 7,500 miles of the Earth on Monday, according to NASA's Jet Propulsion Laboratory.The space rock, called asteroid 2011 MD, is the second space rock to zip extremely close to the Earth this year.The asteroid, with latest size estimates ranging from 16 to 66 feet (5 to 20 meters) wide, was discovered just last week on June 22, but there was never any risk of it impacting the Earth, NASA scientists said. That means asteroid 2011 MD would likely be too small to survive the fiery plunge through the Earth's atmosphere, let alone reach the surface, NASA scientists said. Asteroids this size can be expected to buzz Earth with close shaves about once every six years, they added.The space rock flew well below geosynchronous satellites, which orbit 22,236 miles (35,786 km) above the Earth, but well above the 220-mile (354-km) altitude of the International Space Station.There was little chance that the asteroid would hit a satellite because of the vastness of space and relatively small number of satellites, experts said.

WASHINGTON, July 8 (Xinhua) -- U.S. President Barack Obama on Friday hailed space shuttle Atlantis' final flight in NASA's shuttle program, saying Americans across the country watched with pride as America reached for the heavens once more.Obama expressed his "sincere gratitude" to Atlantis astronauts and space workers because they "helped our country lead the space age.""Today's launch may mark the final flight of the space shuttle, " Obama said in a statement. "But it propels us into the next era of our never-ending adventure to push the very frontiers of exploration and discovery in space."Friday's flight is the 33rd voyage for Atlantis. Its return to the earth later this month will mark the end of the 30-year shuttle program."What a truly awesome day today," said NASA Associate Administrator for Space Operations Bill Gerstenmaier at the STS- 135 postlaunch news conference. "What you saw is the finest launch team and shuttle preparation teams in the world.""It truly was an awesome, spectacular launch," added Kennedy Space Center Director Bob Cabana, who looked ahead to plans for future development beyond the shuttle program as space station operations continue.Atlantis will be the last shuttle to be retired. Discovery was first in March, followed by Endeavour at the beginning of June. Each shuttle will head to a museum.When the U.S. space shuttle program officially ends later this year, the Russian space program's Soyuz capsule will be the only method for transporting astronauts to and from the station.

WASHINGTON, June 16 (Xinhua) -- Cells in the human body are constantly being exposed to stress from environmental chemicals or errors in routine cellular processes. While stress can cause damage, it can also provide the stimulus for undoing the damage. New research by a team of scientists at the University of Rochester has unveiled an important new mechanism that allows cells to recognize when they are under stress and prime the DNA repair machinery to respond to the threat of damage.Their findings will be published Friday in journal Science. Cells in the human body are constantly being exposed to stress from environmental chemicals or errors in routine cellular processes. While stress can cause damage, it can also provide the stimulus for undoing the damage.The scientists, led by biologists Vera Gorbunova and Andrei Seluanov, focused on the most dangerous type of DNA damage -- double strand breaks. Unrepaired, this type of damage can lead to premature aging and cancer. They studied how oxidative stress affects efficiency of DNA repair. Oxidative stress occurs when the body is unable to neutralize the highly-reactive molecules, which are typically produced during routine cellular activities.The research team found that human cells undergoing oxidative stress synthesized more of a protein called SIRT6. By increasing SIRT6 levels, cells were able to stimulate their ability to repair double strand breaks. When the cells were treated with a drug that inactivated SIRT6, DNA repair came to a halt, thus confirming the role of SIRT6 in DNA repair. Gorbunova notes that the SIRT6 protein is structurally related to another protein, SIR2, which has been shown to extend lifespan in multiple model organisms."SIRT6 also affects DNA repair when there is no oxidative stress," explains Gorbunova. "It's just that the effect is magnified when the cells are challenged with even small amounts of oxidative stress."SIRT6 allows the cells to be economical with their resources, priming the repair enzymes only when there is damage that needs to be repaired. Thus SIRT6 may be a master regulator that coordinates stress and DNA repair activities, according to Gorbunova.

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