陕西复读学校实力专业(西安封闭冲刺实力效果好) (今日更新中)

BEIJING, March 22 (Xinhuanet) -- NASA scientists are testing its next-generation Mars rover, which will land on Mars next year, under extreme conditions at space-simulation chamber in California, media reports said Tuesday.Scientists at NASA's Jet Propulsion Laboratory in Pasadena, Calif., say they've installed the Curiosity rover in a space-simulation chamber that can mimic the environment the probe will encounter on Mars.  After the chamber's large door was sealed last week, air was pumped out to near-vacuum pressure, liquid nitrogen in the walls dropped the temperature to minus 130 degrees Celsius, and a bank of powerful lamps simulated the intensity of sunshine on Mars.After the test period, the rover along with other portions of NASA's Mars Science Laboratory spacecraft including the cruise stage, descent stage and backshell -- part of protective covering -- will be shipped to the Kennedy Space Center for final preparation for the launch window from Nov. 25 to Dec. 18, 2011. Curiosity will study whether a selected area of Mars has offered environmental conditions favorable for microbial life and for preserving evidence about whether Martian life has existed.

LOS ANGELES, May 23 (Xinhua) -- NASA's Gravity Recovery And Interior Laboratory spacecraft (Grail) will begin final preparations for a launch on a Moon mission in late summer, the Jet Propulsion Laboratory (JPL) said on Monday.The dynamic duo will orbit the moon to determine the structure of the lunar interior from crust to core and to advance understanding of the thermal evolution of the moon, according to JPL in Pasadena, Los Angeles.After arriving at the Astrotech payload processing facility in Titusville, Florida last week, the Grail twins, known as Grail-A and Grail-B, were removed from their shipping containers Monday. Later this week, they will begin functional testing to verify their state of health, said JPL.The twins were shipped from Lockheed Martin Space Systems, Denver.Over the next four months at the Astrotech facility, the spacecraft will undergo final testing, fueling and packaging in the shroud that will protect them as the Delta II launch vehicle lifts them into space. The spacecraft will then be transported to the Cape Canaveral Air Force Station for installation atop the rocket that will carry them toward the moon, JPL said."We're only a few full moons away from a mission that will reveal clues not only into the history of the moon and Earth, but will provide important data for future lunar exploration," said Maria Zuber, Grail's principal investigator, based at the Massachusetts Institute of Technology.Grail will be carried into space aboard a United Launch Alliance Delta II Heavy rocket lifting off from Launch Complex-19 at the Cape Canaveral Air Force Station in Florida. The launch period opens Sept. 8, 2011, and extends through Oct. 19. For a Sept. 8 liftoff, the launch window opens at 5:37 a.m. PDT (8:37 a.m. EDT) and remains open through 6:16 a.m. PDT (9:16 a.m. EDT).Grail-A and Grail-B will fly in tandem orbits around the moon for several months to measure its gravity field in unprecedented detail.The mission will also answer longstanding questions about Earth' s moon, and provide scientists a better understanding of how Earth and other rocky planets in the solar system formed, according to JPL, which manages the Grail mission.

WASHINGTON, April 25 (Xinhua) -- A class of drugs that shows promise in breast and ovarian cancers with BRCA gene mutations could potentially benefit colorectal cancer patients with a different genetic mutation, a new study from the University of Michigan Comprehensive Cancer Center finds.Working in cell lines from colorectal cancer patients, researchers found that the class of drugs called PARP inhibitors worked against tumors with mutations in the MRE11 gene.About 15 percent of all colorectal cancers have what's called microsatellite instability, a type of error in the DNA. About 82 percent of those tumors have the MRE11 gene mutation."This is a potential broader application for PARP inhibitors, beyond breast and ovarian cancer. This is a class of drug that's already shown safety in early clinical trials and now might benefit some colorectal cancer patients as well," says lead study author Eduardo Vilar-Sanchez, a hematology/oncology fellow at the university, in a statement.The study, which was published Monday in Cancer Research, also found that PARP inhibitors are even more effective when both copies of MRE11 were mutated. Each person carries two copies of each gene, which means mutations can occur in either one or both copies. The researchers suggest that PARP inhibitors could be targeted specifically to colorectal cancer patients who have two copies of the mutated gene.Researchers are planning a phase I clinical trial to look at using PARP inhibitors in colorectal cancer patients with two mutated copies of MRE11. Future trials are being considered using PARP inhibitors to prevent colorectal cancer and other cancers in people with Lynch syndrome whose tumors have this mutation.Microsatellite instability is also seen in prostate cancer and endometrial cancer, suggesting potential for PARP inhibitors to play a role in additional types of cancer as well, Vilar-Sanchez says, adding that more research is needed in these areas.

PANAMA CITY, April 17 (Xinhua) -- In Latin America there are 600,000 people infected with the Acquired Immune Deficiency Syndrome (AIDS) and about 50 percent of them receive treatment, regional director of UNAIDS for Latin America Cesar Nunez said on Sunday."We have to work a lot for the other half get treatment," Nunez told Xinhua during the 124th Assembly of the Inter-parliamentarian Assembly hosted in Panama City from April 15 to 20.Nunez urged the governments of the region to redouble efforts to control this pandemic, by improving the prevention campaigns to stop new infections."The availability of the medicines has grown in the last 10 years and the countries have taken this commitment, however, the number of infections each time is bigger than the number of people we can treat," he said.According to Nunez, despite the increase of new infections among women, the men sector continue being one of the most affected social groups by this virus."In Latin America we have an epidemic where the most affected are men, followed by homosexuals, lesbians and sex workers," he said.Nunez said that during the meeting with the parliamentarians, they exchanged experiences to contribute to improve the management of this disease."We have met with parliamentarians who have voted for more budget to buy more medicines, in favor of laws for more education about this topic and participation in the exchange of information to know about the advances and backwards of the fight against Aids," he said.Some 800 parliamentarians from 125 countries attended the 124th Assembly to debate the recent events in the Arab world, the disaster in Japan and sustainable development.

CHICAGO, Jan. 21 (Xinhua) -- Chinese President Hu Jintao left Chicago for China on Friday after concluding a state visit to the United States, during which he and his U.S. counterpart Barack Obama agreed to build a China-U.S. cooperative partnership based on mutual respect and mutual benefit.Hu, who began his four-day visit Tuesday, had extensive and in-depth discussions with Obama at the White House on Wednesday on major bilateral, regional and world issues.Chinese President Hu Jintao shakes hands with U.S. President Barack Obama during a bilateral meeting at the White House in Washington, the United States, Jan. 19, 2011.The two sides reached "important agreement on China-U.S. relations and major international and regional issues of shared interests," the Chinese president said when he and Obama met the press following their discussions."We both agree to further push forward the positive, cooperative and comprehensive China-U.S. relationship," Hu said, adding that both sides also pledged to forge "a China-U.S. cooperative partnership based on mutual respect and mutual benefit" for the benefit of the two countries and beyond.

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