贵阳白癜风研究(贵阳哪个医院治疗白癜风正规) (今日更新中)

LOS ANGELES, June 24 (Xinhua) -- Near-Earth asteroid 2011 MD will whip past Earth on June 27, but will not pose any threat, NASA's Jet Propulsion Laboratory (JPL) said on Friday.The asteroid will pass only 12,000 kilometers (7,500 miles) above the Earth's surface at about 9:30 EDT, according to JPL in Pasadena, Los Angeles.This small asteroid, only 5-20 meters in diameter, is in a very Earth-like orbit about the Sun, but an orbital analysis indicates there is no chance it will actually strike Earth on Monday, JPL said.If a rocky asteroid the size of 2011 MD were to enter Earth's atmosphere, it would be expected to burn up high in the atmosphere and cause no damage to Earth's surface, said JPL.The accompanying diagram gives a view of the asteroid's trajectory from the general direction of the Sun. This view indicates that 2011 MD will reach its closest Earth approach point in extreme southern latitudes (in fact over the southern Atlantic Ocean), according to JPL. The incoming trajectory leg passes several thousand kilometers outside the geosynchronous ring of satellites and the outgoing leg passes well inside the ring, JPL said.For a brief time, it may be bright enough to be seen even with a modest-sized telescope.One would expect an object of this size to come this close to Earth about every six years on average.The asteroid was discovered by the LINEAR near-Earth object discovery team observing from Socorro, New Mexico.

WASHINGTON, June 6 (Xinhua) -- Forests in many regions are becoming larger carbon sinks thanks to higher density, U.S. and European researchers say in a new report.In Europe and North America, increased density significantly raised carbon storage despite little or no expansion of forest area, according to the study, led by Aapo Rautiainen of the University of Helsinki, Finland, and published Monday in the on- line, open-access journal PLoS One.Even in the South American nations studied, more density helped maintain regional carbon levels in the face of deforestation.The researchers analyzed information from 68 nations, which together account for 72 percent of the world's forested land and 68 percent of reported carbon mass. They conclude that managing forests for timber growth and density offers a way to increase stored carbon, even with little or no expansion of forest area."In 2004 emissions and removals of carbon dioxide from land use, land-use change and forestry comprised about one fifth of total emissions. Tempering the fifth by slowing or reversing the loss of carbon in forests would be a worthwhile mitigation. The great role of density means that not only conservation of forest area but also managing denser, healthier forests can mitigate carbon emission," says Rautiainen.

WASHINGTON, Aug. 16 (Xinhua) -- The White House announced Tuesday that the U.S. Departments of Agriculture, Energy and Navy will invest up to 510 million U.S. dollars in partnership with the private sector to facilitate the country's biofuel industry development."Biofuels are an important part of reducing America's dependence on foreign oil and creating jobs here at home," U.S. President Barack Obama said in a White House statement.The initiative is a response to a directive from Obama issued in March as part of the Blueprint for A Secure Energy Future, the administration's framework for reducing dependence on foreign oil."But supporting biofuels cannot be the role of government alone. That's why we're partnering with the private sector to speed development of next-generation biofuels that will help us continue to take steps towards energy independence and strengthen communities across our country," Obama added.The joint plan calls for the three departments to invest up to 510 million dollars in the next three years, which will require substantial cost share from private industry, in a bid to reduce U. S. reliance on foreign oil and create jobs at home."By building a national biofuels industry, we are creating construction jobs, refinery jobs and economic opportunity in rural communities throughout the country," said U.S. Agriculture Secretary Tom Vilsack.White House figures revealed that the world's largest economy spends more than 300 billion dollars on imported crude oil every year.With a slackening economic recovery and the government's approval rate at a record low level, the Obama administration is rolling out a string of measures in recent days to accelerate economic growth and job creation.

HONG KONG, July 19 (Xinhua) -- A gene controlled by male hormone was critical for the growth of liver tumor, leading to a higher incidence of the disease in men than in women, according to the Chinese University of Hong Kong which made the results public on Tuesday.There is a significant gender bias in liver cancer incidence. In Hong Kong, men are three times more likely to develop liver cancer than women. Such phenomenon prompted researchers from the university to carry out a genomic location analysis in liver cancer cells starting from 2008.The researchers discovered, out of 17,000 human genes, that a gene called Cell Cycle-Related Kinase (CCRK) was directly controlled by androgen receptor. They further found that CCRK was critical for the induction of signaling pathway leading to abnormal liver cell growth and tumor formation.The results also reveal that 70 percent of patients with liver cancer were found to produce high levels of CCRK. More importantly, these patients were more likely to have late-stage cancers and lived shorter than those with low CCRK level.Using mouse models, the researchers found that either lowering the level or blocking the signaling pathway of CCRK in liver cancer cells could significantly reduce the tumor growth rate.The study has validated that CCRK is an important gene that has potential to cause liver cancer and the gene can be tested as a new targeted therapy in future.Vice-Chancellor of the university Joseph Sung, who is also team leader of the research project, said the results explained why men have a higher risk of liver cancer than women and helped push ahead with the development of a novel treatment of the disease.The above study results were published online in July in Journal of Clinical Investigation.

BEIJING, Aug. 22 (Xinhuanet) -- U.S. presidential candidate Rick Perry's controversial stem-cell treatment may inspire desperate patients to follow his lead while causing medical and legal concerns, according to media reports Monday.The Texas governor underwent a procedure on July 1 where stem cells, made from fat taken from his body, were put into his bloodstream to see if they might find their way to fix a bad back.The treatment carries potential risks ranging from blood clots to infection to cancer and may even run afoul of federal rules, doctors say. File photo of U.S. Republican presidential candidate Texas Governor Rick Perry."As a highly influential person of power, Perry’s actions have the unfortunate potential to push desperate patients into the clinic of quacks,” Harvard’s stem cell expert George Daley told the Associated Press.Worries about the safety and wisdom of this treatment are widespread among stem cell researchers as such a treatment has not been thoroughly vetted by researchers or approved by the FDA.

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