昌吉包皮割不割(佳美引产价格表) (今日更新中)

LOS ANGELES, July 3 (Xinhua) -- Warming of the ocean's subsurface layers will melt underwater portions of the Greenland and Antarctic ice sheets faster than previously thought, increasing the sea level more than already projected, a new study suggests.The subsurface ocean layers surrounding the polar ice sheets will warm substantially as global warming progresses, according to the study led by researchers from the University of Arizona (UA).In addition to being exposed to warming air, underwater portions of the polar ice sheets and glaciers will be bathed in warming seawater, said the study appearing on the website of the American Association for the Advancement of Science (AAAS) on Sunday.The research, based on 19 state-of-the-art climate models, proposes a new mechanism by which global warming will accelerate the melting of the great ice sheets during this century and the next."To my knowledge, this study is the first to quantify and compare future ocean warming around the Greenland and the Antarctic ice sheets using an ensemble of models," said lead author Jianjun Yin, a UA assistant professor of geosciences.According to the study, the subsurface ocean along the Greenland coast could increase as much as 3.6 F (2 C) by 2100.Most previous research has focused on how increases in atmospheric temperatures would affect the ice sheets, he said."Ocean warming is very important compared to atmospheric warming because water has a much larger heat capacity than air," Yin said. "If you put an ice cube in a warm room, it will melt in several hours. But if you put an ice cube in a cup of warm water, it will disappear in just minutes."Given a mid-level increase in greenhouse gases, the researchers found the ocean layer about 650 to 1,650 feet (200 to 500 meters) below the surface would warm, on average, about 1.8 F (1 C) by 2100. Along the Greenland coast, that layer would warm twice as much, but along Antarctica would warm less, only 0.9 F (0.5 C)."No one has noticed this discrepancy before -- that the subsurface oceans surrounding Greenland and Antarctica warm very differently," Yin said.Part of the warming in the North comes from the Gulf Stream carrying warm subtropical waters north. By contrast, the Antarctic Circumpolar Current blocks some of the subtropical warmth from entering the Antarctic's coastal waters.Even so, the Antarctic ice sheet will be bathed in warming waters, according to the study.This paper adds to the evidence that sea level would rise by the end of this century by around one meter and a good deal more in succeeding centuries, the study noted.The study, "Different Magnitudes of Projected Subsurface Ocean Warming Around Greenland and Antarctica," is scheduled for the upcoming edition of Nature Geoscience later this month.

BEIJING, Sept. 6 (Xinhuanet) -- The amount of space junks floating in Earth's orbit has reached a critical level, warned scientists.The future space missions may become too dangerous to fly for a risk of colliding with space junks, said a report released recently by the U.S. National Research Council (NRC).The kinds of space junks range from huge, the report said, there are thousands of discarded satellites and rocket boosters and countless tiny pieces of daily gabages from space missions.The debris are traveling in orbit at 17,500mph, at such a speed even a tiny clash can destroy a spacecraft.The NRC recommended that NASA should launch a plan to clean up the floating debris and called on other major space nations' cooperation."The current space environment is growing increasingly hazardous to spacecraft and astronauts," said Kessler, an ex-NASA researcher, "NASA needs to determine the best path forward for tackling the multifaceted problems caused by meteoroids and orbital debris that put human and robotic space operations at risk."

CANBERRA, June 6 (Xinhua) -- Australian beef is not to blame for a recent outbreak of E.coli in Japan, Meat and Livestock Australia confirmed on Monday.Twenty people have fallen ill in Japan's Toyama prefecture, with 15 of them infected with the O157 strain of E.coli after eating at a popular Korean-style barbecue restaurant chain, Gyukaka, on May 6.The operators of the restaurant chain, REINS International, said they suspected the bacterium might have been carried by beef imported from Australia.After conducting an investigation into the Japanese outbreak, regional manager for Meat and Livestock Australia, Melanie Brock, said testing shows Australian beef was not the source of the outbreak."The Toyama prefecture health authorities have confirmed following a thorough inspection that imported Australian beef was not the source of an incident of E.coli," Brock said in a statement on Monday."The authorities continue to investigate other food consumed by the affected customers."Brock said Australian beef has long been recognized by the Japanese trade and consumers for its strong safety record.Brock added that Australian beef for export to Japan is processed under the veterinary supervision of the Australian Quarantine and Inspection Service, and is recognized internationally as bearing a high hygienic standard.

LOS ANGELES, May 30 (Xinhua) -- The American Academy of Pediatrics (AAP) warned on Monday that children should keep away from energy drinks which may be dangerous for minors.The AAP urged young children and teens to avoid energy drinks entirely, saying routine consumption of sports drinks should be limited or eliminated.Energy drinks include such popular brands as Red Bull, AMP and Rockstar, the AAP said in a report.These drinks, the report said, tend to be heavily caffeinated, potentially having several times the level of caffeine found in a cup of coffee.In addition, manufacturers often add sugar and herbal stimulants such as guarana and taurine to the drinks, which are popular among kids, according to the report."There's no place for energy drinks for kids," said report co-author Dr. Marcie Beth Schneider, an adolescent physician in Greenwich, Connecticut. "There's a place for sports drinks, but that place is very specific."The caffeine in energy drinks can lead to high blood pressure, high heart rate and insomnia, she said.The other ingredients can boost the power of the caffeine, she said, adding that the drinks will have a greater effect on children because they're smaller than adults."Kids don't need to have this," she said. "This is not something they should be drinking."Schneider declined to identify any energy drinks that may be better than others for kids who insist on drinking them. If kids use energy drinks because they're tired, she said, they should get more rest instead of chugging caffeine.Half of the nation's 5,448 reported caffeine overdoses in 2007 were in people under age 19, although it's not known how many of the cases were the result of energy drink consumption, according to statistics provided by the AAP.

MOSCOW, Aug. 24 (Xinhua) -- A Russian Progress cargo ship crashed into Siberia after failing to reach the right orbit Wednesday. The crash marked the second failure in space launch in less than a week and the third in this year, prompting local media to suspect a major reshuffle in Russia's space industry.UNPRECEDENTED FAILUREThe Progress M-12M unmanned freighter was launched to the International Space Station from Baikonur space center in Kazakhstan on Wednesday. It was expected to reach a near-Earth orbit in about nine minutes after launch.However, after the 325th second of the flight, which was just a few seconds before the vessel should reach the orbit, the ground control center lost it.Russian space agency Roscosmos confirmed later that the cargo ship failed to reach the orbit and fell down. Russian Progress M-12M cargo ship is launched to the International Space Station from Baikonur space center in Kazakhstan on Wednesday, Aug. 24, 2011. It has failed to reach the orbit, the Interfax news agency reported.The malfunction of the Soyuz-U rocket's engine was generally believed to be the cause of the accident, according to local media.A source in the space industry said the spaceship had sent a breakdown report while separating from the Soyuz rocket.Some unconfirmed reports said the fuel tank of the booster leaked and the engine was automatically turned off to avoid explosion.The wreckage of the Progress cargo ship has already fallen in southern Siberia's Altai Republic, where a big explosion was heard by locals, reported RIA Novosti news agency.A state investigation committee has been formed to look into the first ever loss of a Progress freighter.CONCERNS OVER FUTUREThe unprecedented accident raised concerns over the reserves of the six crew members on board the ISS.The ship was loaded with over 3.5 tons of supplies for the ISS, including scientific materials, oxygen, water and food.According to Russia's Ground Control, the loss of these supplies will not affect the ISS crew as there are enough stocks of necessities for two to three months.Also, there is no need for premature return of the crew, said Vladimir Solovyov, a space official.However, it still casts some shadow over the ISS program that relies on Russia exclusively following the retirement of U.S. shuttles.A source from the Russian space industry said the scheduled launches of the Soyuz rockets are likely to be suspended until the reasons of the accident are established.This means that current crew members of the ISS would likely stay longer in the space than planned, as the new members might not be able to replace them on schedule, the source explained. Solovyov said the launch of the next Progress is scheduled for October 28.So far, Roscosmos has refrained from comments regarding the possible halt in manned missions aboard Soyuz carrier rockets."Comments will follow. Now it is necessary to determine the causes of today's abortive launch of a Soyuz-u carrier rocket with the Progress M-2M transport ship," Roscosmos told Itar-Tass news agency.Local media raised the prospect of a major reshuffle in Russia' s space industry as the country has lost a total of six space vehicles over the past nine months.On Aug. 18, a carrier rocket Proton-M failed to deliver to the orbit communication satellite Express-AM4. Earlier in February, Russia had lost a satellite named Geo-IK2.In December 2010, a booster malfunction resulted in the loss of three satellites in the global positioning and navigation system GLONASS.

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