洛川有算卦准的地方吗(修武哪里有算命比较准的人) (今日更新中)

LOS ANGELES, June 17 (Xinhua) -- The size of low-oxygen zones created by respiring bacteria is extremely sensitive to changes in depth caused by oscillations in climate, thus posing a distant threat to marine life, a new study suggests."The growth of low-oxygen regions is cause for concern because of the detrimental effects on marine populations -- entire ecosystems can die off when marine life cannot escape the low- oxygen water," said lead researcher Curtis Deutsch, assistant professor of atmospheric and oceanic sciences at University of California, Los Angeles."There are widespread areas of the ocean where marine life has had to flee or develop very peculiar adaptations to survive in low- oxygen conditions," Deutsch said in the study to be published in an upcoming print edition of the journal Science.A team led byDeutsch used a specialized computer simulation to demonstrate for the first time that fluctuations in climate can drastically affect the habitability of marine ecosystems.The study also showed that in addition to consuming oxygen, marine bacteria are causing the depletion of nitrogen, an essential nutrient necessary for the survival of most types of algae."We found there is a mechanism that connects climate and its effect on oxygen to the removal of nitrogen from the ocean," Deutsch said. "Our climate acts to change the total amount of nutrients in the ocean over the timescale of decades."Low-oxygen zones are created by bacteria living in the deeper layers of the ocean that consume oxygen by feeding on dead algae that settle from the surface. Just as mountain climbers might feel adverse effects at high altitudes from a lack of air, marine animals that require oxygen to breathe find it difficult or impossible to live in these oxygen-depleted environments, Deutsch said.Sea surface temperatures vary over the course of decades through a climate pattern called the Pacific Decadal Oscillation, during which small changes in depth occur for existing low-oxygen regions, Deutsch said. Low-oxygen regions that rise to warmer, shallower waters expand as bacteria become more active; regions that sink to colder, deeper waters shrink as the bacteria become more sluggish, as if placed in a refrigerator."We have shown for the first time that these low-oxygen regions are intrinsically very sensitive to small changes in climate," Deutsch said in remarks published Friday by the American Association for the Advancement of Science on its website. "That is what makes the growth and shrinkage of these low-oxygen regions so dramatic."Molecular oxygen from the atmosphere dissolves in sea water at the surface and is transported to deeper levels by ocean circulation currents, where it is consumed by bacteria, Deutsch said."The oxygen consumed by bacteria within the deeper layers of the ocean is replaced by water circulating through the ocean," he said. "The water is constantly stirring itself up, allowing the deeper parts to occasionally take a breath from the atmosphere."A lack of oxygen is not the only thing fish and other marine life must contend with, according to Deutsch. When oxygen is very low, the bacteria will begin to consume nitrogen, one of the most important nutrients that sustain marine life."Almost all algae, the very base of the food chain, use nitrogen to stay alive," Deutsch said. "As these low-oxygen regions expand and contract, the amount of nutrients available to keep the algae alive at the surface of the ocean goes up and down. "Understanding the causes of oxygen and nitrogen depletion in the ocean is important for determining the effect on fisheries and fish populations, he said.

WASHINGTON, July 12 (Xinhua) -- Two U.S. astronauts stepped out the International Space Station on Tuesday to retrieve a failed ammonia pump, which is the last spacewalk of the shuttle era, NASA announced.Space station astronauts Mike Fossum and Ron Garan completed the six-hour, 31-minute spacewalk at 3:53 p.m. EDT (1953 GMT). The duo retrieved a pump module from an external stowage platform on station and store it in shuttle Atlantis' cargo bay for return to Earth.The pump module failed in 2010, shutting down half of the space station's cooling system. Engineers will evaluate the module to determine the cause of the failure and plan to refurbish it for use as a spare.The astronauts also attached a Robotic Refueling Module experiment to the space station, which aims to test technologies for repairing and refueling satellites in space.It was the 249th spacewalk by U.S. astronauts and the 160th spacewalk in support of space station assembly and maintenance, totaling 1009 hours, nine minutes.Atlantis lifted off on Friday morning from Kennedy Space Center in Florida, on the 135th and final flight in NASA's shuttle program. Its return to the earth later this month will mark the end of the 30-year shuttle program.

JIUQUAN, Gansu, Aug. 18 (Xinhua) -- China's experimental orbiter SJ-11-04, which was launched by a Long March II-C rocket Thursday, failed to enter the designated orbit due to a malfunction of the rocket.The rocket experienced malfunction during the flight following its launch from Jiuquan Satellite Launch Center at 5:28 p.m. Beijing Time in northwest Gansu Province.The specific cause of the failure is being analyzed.

BEIJING, July 3 (Xinhuanet) -- The Atlantis mission to be launched by NASA on July 8 will not be an end to the space age, as some media suggest.Although it is the final mission of the space shuttle, it will open up "the next chapter" in the United States' space exploration, NASA's administrator Charles Bolden Jr said at the National Press Club in Washington on Friday."When I hear people say - or listen to media reports - that the final shuttle flight marks the end of US human space flight, I have to say . . . these folks must be living on another planet," he said."As a former astronaut and the current NASA administrator, I'm here to tell you that American leadership in space will continue for at least the next half-century because we have laid the foundation for success - and for NASA, failure is not an option," he said.NASA administrator Charles Bolden Jr drew a lot of media attention during his speech at the National Press Club in Washington DC.One of the foundations is the "unprecedented" research capabilities the International Space Station (ISS) now possesses, largely thanks to the space shuttle missions.Although some media imply that "the game will be up" once the ISS is out of orbit in 2020, he said the splendid research results and rich knowledge astronauts and scientists have accumulated through more than 1,200 experiments since 1998 have laid out "a stepping-stone to the rest of the solar system and the tip of what comes next".As NASA turns a new page, it will "focus on deep space exploration", while leaving US private companies to operate low Earth orbit transportation systems for tourism and business, he said.NASA will develop "a deep space crew vehicle and an evolvable heavy-lift rocket," he said. The moon, asteroids and Mars will be the next destinations for humans to live and work, he said."We will maintain and grow US leadership in space and derive all the benefits that flow from it. Tomorrow's space program is taking shape right now," he said.

来源：资阳报