济南痛风怎么办吃什么(济南脚腕痛风怎么治) (今日更新中)

BEIJING, Sept. 23 (Xinhua) -- A defunct U.S. satellite is expected to crash down to Earth Friday, with nobody knowing where or when exactly it will hit. This was avoidable, a Chinese expert said Thursday.Pang Zhihao, a researcher from the Chinese Research Institute of Space Technology, told Xinhua that the crash could have been avoided had the satellite been put into a higher orbit, or manipulated to drop in the South Pacific when it had abundant fuel. It would pose no threat to Earth if these measures had been taken.NASA's tumbling, 5,900 kg Upper Atmosphere Research Satellite, or UARS, is the first of such man-made space vehicles that have been launched into outer space according to the agency's Mission to Planet Earth. The mission was launched in the 1990s.The mission is designed to provide data for better understanding Earth's upper atmosphere and the effects of natural and human interactions on the atmosphere.The satellite was deactivated in 2005 as it ran out of fuel and was left orbiting Earth like a big piece of space junk.There are other cases of defunct satellites. The European Space Agency said earlier its observation satellite ERS-2 has run out of fuel and is deorbiting. It would therefore also crash sooner or later.Pang said all countries which are operating space vehicles should take care of their own spacecrafts so that they won't pose any danger.The expert also said that the public need not worry too much.Pang said most spacecrafts will be incinerated upon re-entering Earth's atmosphere, and the debris will mostly likely fall into the ocean or hit an uninhabited area. In addition, a debris tracker is able to give a comparatively accurate prediction where the craft will fall about two hours before it hits Earth, giving residents, if there are any, time to evacuate.He added that there are several ways to minimize the threat of decommissioned spacecrafts, like putting them into higher orbits and crashing them into designated waters.Scientific progress would possibly bring about more ways of dealing with tumbling satellites. Scientists have already been trying to build spacecrafts with degradable materials so that they can self-destruct when re-entering Earth's atmosphere.

WASHINGTON, July 18 (Xinhua) -- The U.S. National Aeronautics and Space Administration (NASA) on Monday commemorated the 90th birthday of astronaut John Glenn, the first U.S. astronaut to orbit the Earth and also the oldest person to fly to space when he launched on the space shuttle in 1998."John Glenn is a legend, and NASA sends him our best wishes on this major personal milestone," NASA Administrator Charles Bolden said in a statement. "John's legacy and contributions to the continued progress of human spaceflight are immense. His example is one we continue to emulate as we push toward farther destinations in the solar system."After a distinguished flying career with the Marines in World War II and Korea, Glenn joined NASA in 1959 as one of the country' s first astronauts in Project Mercury. On Feb. 20, 1962, Glenn piloted the Mercury-Atlas 6 "Friendship 7" spacecraft on the first U.S. manned orbital mission. He launched from NASA's Kennedy Space Center in Florida to successfully complete three orbits of the Earth.Glenn flew to space again on the STS-95 mission in 1998 aboard the space shuttle Discovery. As a mission specialist, Glenn supported deployment of a variety of research payloads and participated in investigations about spaceflight and the aging process.

TAMPA, the United States, June 18 (Xinhua) -- The HIV/AIDS patients in the U.S. state of Florida are in dispute with state authorities over a proposal to impose tighter restrictions on those who qualify for drugs provided by the state's AIDS Drug Assistance Program (ADAP).According to the proposed restrictions, individuals would have to earn less than 21,000 U.S. dollars annually to qualify for ADAP drugs. If approved by the Florida Department of Health (FDH), this would affect approximately 1,150 HIV/AIDS patients."The FDH is currently looking at the number of cost containment activities, including altering the financial eligibility for ADAP services," said FDH's press secretary Jessica Hammonds. "After soliciting public input on this matter, the department is in the final stages of evaluating the matter."The Florida ADAP program serves almost 9,500 clients, each of whom receiving 8,600 dollars in funding annually, Hammonds said. There are still another 3,482 on a waiting list.Four FDH sponsored public hearings were held in April and May on the proposal to reduce HIV/AIDS funding. Two were held in Miami, one in Tampa, and the other one was held in the state capital city of Tallahassee. Over 1,000 people attended the hearings.The issue has become so ubiquitous that it caught the attention of the Elton John AIDS Foundation (EJAF), created by the popular entertainer of the same name.

LOS ANGELES, June 23 (Xinhua) -- The sun and its inner planets may have formed differently than previously thought, NASA's Jet Propulsion Laboratory (JPL) said on Thursday.Data revealed differences between the sun and planets in oxygen and nitrogen, which are two of the most abundant elements in our solar system, said JPL in Pasadena, Los Angeles.Although the difference is slight, the implications could help determine how our solar system evolved, JPL said.NASA researchers drew the conclusion after analyzing samples returned by NASA's 2004 Genesis mission, according to JPL.The air on Earth contains three different kinds of oxygen atoms which are differentiated by the number of neutrons they contain. Nearly 100 percent of oxygen atoms in the solar system are composed of O-16, but there are also tiny amounts of more exotic oxygen isotopes called O-17 and O-18. Researchers studying the oxygen of Genesis samples found that the percentage of O-16 in the sun is slightly higher than on Earth or on other terrestrial planets. The other isotopes' percentages were slightly lower."We found that Earth, the moon, as well as Martian and other meteorites which are samples of asteroids, have a lower concentration of the O-16 than does the sun," said Kevin McKeegan, a Genesis co-investigator from University of California, Los Angeles (UCLA) and the lead author of one of two papers published this week in Science journal. "The implication is that we did not form out of the same solar nebula materials that created the sun -- just how and why remains to be discovered." Another paper detailed differences between the sun and planets in the element nitrogen. Like oxygen, nitrogen has one isotope, N- 14, that makes up nearly 100 percent of the atoms in the solar system, but there is also a tiny amount of N-15. Researchers studying the same samples saw that when compared to Earth's atmosphere, nitrogen in the sun and Jupiter has slightly more N-14, but 40 percent less N-15. Both the sun and Jupiter appear to have the same nitrogen composition. As is the case for oxygen, Earth and the rest of the inner solar system are very different in nitrogen."These findings show that all solar system objects including the terrestrial planets, meteorites and comets are anomalous compared to the initial composition of the nebula from which the solar system formed," said Bernard Marty, a Genesis co- investigator from Petrographic and Geochemical Research Center in Fracne and the lead author of the other new Science paper. " Understanding the cause of such a heterogeneity will impact our view on the formation of the solar system."Data were obtained from analysis of samples Genesis collected from the solar wind, or material ejected from the outer portion of the sun. This material can be thought of as a fossil of our nebula because the preponderance of scientific evidence suggests that the outer layer of our sun has not changed measurably for billions of years."The sun houses more than 99 percent of the material currently in our solar system, so it's a good idea to get to know it better, " said Genesis Principal Investigator Don Burnett of the California Institute of Technology, Pasadena, California. "While it was more challenging than expected, we have answered some important questions, and like all successful missions, generated plenty more."Genesis was launched in August 2000. The spacecraft traveled to Earth's L1 Lagrange Point about one million miles from Earth, where it remained for 886 days between 2001 and 2004, passively collecting solar-wind samples.JPL managed the Genesis mission for NASA's Science Mission Directorate, Washington. The Genesis mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Alasca.

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