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LOS ANGELES, July 22 (Xinhua) -- Two teams of astronomers have discovered the largest and farthest reservoir of water ever detected in the universe, NASA's Jet Propulsion Laboratory (JPL) said on Friday.The water, equivalent to 140 trillion times all the water in the world's ocean, surrounds a huge, feeding black hole, called a quasar, more than 12 billion light-years away, according to JPL in Pasadena, California."The environment around this quasar is very unique in that it's producing this huge mass of water," said Matt Bradford, a scientist at JPL. "It's another demonstration that water is pervasive throughout the universe, even at the very earliest times. "This artist's concept illustrates a quasar, or feeding black hole, similar to APM 08279+5255, where astronomers discovered huge amounts of water vapor. Gas and dust likely form a torus around the central black hole, with clouds of charged gas above and below. X-rays emerge from the very central region, while thermal infrared radiation is emitted by dust throughout most of the torus. While this figure shows the quasar's torus approximately edge-on, the torus around APM 08279+5255 is likely positioned face-on from our point of view.A quasar is powered by an enormous black hole that steadily consumes a surrounding disk of gas and dust. As it eats, the quasar spews out huge amounts of energy. Both groups of astronomers studied a particular quasar called APM 08279+5255, which harbors a black hole 20 billion times more massive than the sun and produces as much energy as a thousand trillion suns.Astronomers expected water vapor to be present even in the early, distant universe, but had not detected it this far away before. There's water vapor in the Milky Way, although the total amount is 4,000 times less than in the quasar, because most of the Milky Way's water is frozen in ice. Water vapor is an important trace gas that reveals the nature of the quasar. In this particular quasar, the water vapor is distributed around the black hole in a gaseous region spanning hundreds of light-years in size (a light-year is about six trillion miles).Its presence indicates that the quasar is bathing the gas in X- rays and infrared radiation, and that the gas is unusually warm and dense by astronomical standards, JPL said.Although the gas is at a chilly minus 63 degrees Fahrenheit ( minus 53 degrees Celsius) and is 300 trillion times less dense than Earth's atmosphere, it's still five times hotter and 10 to 100 times denser than what's typical in galaxies like the Milky Way, said JPL.Measurements of the water vapor and of other molecules, such as carbon monoxide, suggest there is enough gas to feed the black hole until it grows to about six times its size, JPL said.Whether this will happen is not clear, the astronomers say, since some of the gas may end up condensing into stars or might be ejected from the quasar.Bradford's team made their observations starting in 2008, using an instrument called "Z-Spec" at the California Institute of Technology's (Caltech's) Submillimeter Observatory, a 33-foot (10- meter) telescope near the summit of Mauna Kea in Hawaii. Follow-up observations were made with the Combined Array for Research in Millimeter-Wave Astronomy (CARMA), an array of radio dishes in the Inyo Mountains of Southern California.The second group, led by Dariusz Lis, senior research associate in physics at Caltech and deputy director of the Caltech Submillimeter Observatory, used the Plateau de Bure Interferometer in the French Alps to find water. In 2010, Lis's team serendipitously detected water in APM 8279+5255, observing one spectral signature.Bradford's team was able to get more information about the water, including its enormous mass, because they detected several spectral signatures of the water, according to JPL.

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.

BEIJING, Aug. 24 (Xinhuanet) -- Married patients are more likely than single ones to survive 15 years after heart surgery, according to a study online in the Health Psychology.Researchers of the study tracked 225 people who underwent coronary bypass surgery from 1987 to 1990. They found that 124 patients of them, or about 55 percent, survived for at least the next 15 years. And 61 percent of the married patients and 30 percent of the unmarried survived.Kathleen King, lead author of study, said that the close connection to another person in a marriage lengthened patients’ lives."Marriage gives you purpose in life, and feeling like you have a reason to live is an important part of doing the things you need to do to stay alive," Harry T. Reis, co-author of the study, said. "Married people also help each other; remind each other it's time to take their pills. And they probably eat healthier."However, the marriage quality had different effects on the survival odds between men and women. Men who had bypass surgery lived longer by virtue of simply being married, regardless of how happy or miserable the union, but the marriage quality had more impact on women's survival after surgery. 83 percent of the happily married women had survived, compared with 28 percent of the less happily married women and 27 percent of the single women. Among the men, 83 percent of the happily married were still alive, compared with 60 percent of the less happily married and 36 percent of the single."The most dramatic thing to me is [that] just being married, especially if you had a happy marriage, had that big an effect 15 years later," King told ABCNews.com.Marriage does not only have a positive effect on the survival of patients after heart surgery, but also benefits patients with other diseases.In recent years, a number of studies have showed several apparent health benefits of marriage. For instance, it might slightly add the odds of survival from colon cancer and help reduce pain in rheumatoid arthritis patients.

XICHANG, Sichuan, Aug. 12 (Xinhua) -- China launched a communications satellite PAKSAT-1R for Pakistan at 0:15 a.m. Friday from the Xichang Satellite Launch Center in southwest China's Sichuan Province.The satellite was carried by a Long March-3B carrier rocket, according to the launch center. It is China's first in-orbit delivery to Asian customers and also the first commercial satellite export to international users this year.According to statistics from the control center, the satellite successfully separated from its carrier rocket and entered geostationary transfer orbit as scheduled, 26 minutes after being launched.PAKSAT-1R will provide a range of services, including broadband Internet, telecom and broadcasting, covering some regions of Europe, South Asia, the Middle East, and the eastern Africa.The contract for the PAKSAT-1R was signed in 2008 between China Great Wall Industry Corporation and the Space and Upper Atmosphere Research Commission of Pakistan.China and Pakistan share a long history of space technology cooperation. Pakistan's first low-orbit satellite, BADR-A, was launched by China in 1990 with Long March 2E rocket.

WASHINGTON, Aug. 18 (Xinhua) -- Black scientists were significantly less likely than their white counterparts to receive research funding from the National Institutes of Health (NIH), according to an analysis of data from 2000 to 2006.University of Kansas Professor of Economics Donna Ginther was the lead author on the study commissioned by the NIH, which will appear Friday in journal Science.The researchers found a 10 percentage point gap in research funding -- even after taking into consideration demographics, education and training, employer characteristics, NIH experience and research productivity. For example, for every 100 grants submitted to NIH, 30 grants from white applicants were funded, compared to 20 grants for black applicants.Applications for NIH funding go through peer review that considers the significance, innovation and approach of grant applications, the investigator(s) and the research environment. About half of the applications are determined to be worth scoring. Among those scored, budgets and NIH Institutes priorities determine which applications are funded. Priorities can vary by year and by Institute.The study found that applications from black researchers were less likely to be scored and on average had worse scores. After controlling for the score of the grant, there were no race or ethnicity differences in funding.Applicants self-identify race, ethnicity and gender, but that information is not available during the peer review. However, biographical facts that are included in the review materials can provide clues to the identity of the applicants.The research suggests it is possible that cumulative advantage may explain the funding differences."Small differences in access to research resources and mentoring during training or at the beginning of a career may accumulate to become large between-group differences," the paper says.Additionally, the paper suggests further research is needed to determine why black researchers are less likely to be funded.NIH Director Francis Collins and Principal Deputy Director Lawrence Tabak call the findings unacceptable and commit to immediate action by the NIH."NIH commissioned this study because we want to learn more about the challenges facing the scientific community and address them head on. The results of this study are disturbing and disheartening, and we are committed to taking action," said Collins in an accompanying commentary. "The strength of the U.S. scientific enterprise depends upon our ability to recruit and retain the brightest minds, regardless of race or ethnicity. This study shows that we still have a long way to go."NIH initiated the study in 2008 to determine if researchers of different races and ethnicities with similar research records and affiliations had similar likelihoods of being awarded a new NIH research project grant.