许昌市智能美甲加盟电话多少钱(榆林市优田美甲加盟电话多少钱) (今日更新中)

WASHINGTON, June 15 (Xinhua) -- Using the deepest X-ray image ever taken, astronomers found the first direct evidence that massive black holes were common in the early universe, the U.S. National Aeronautics and Space Administration (NASA) said Wednesday in a statement.The discovery from NASA's Chandra X-ray Observatory shows that very young black holes grew more aggressively than previously thought, in tandem with the growth of their host galaxies.By pointing Chandra at a patch of sky for more than six weeks, astronomers obtained what is known as the Chandra Deep Field South (CDFS). When combined with very deep optical and infrared images from NASA's Hubble Space Telescope, the new Chandra data allowed astronomers to search for black holes in 200 distant galaxies, from when the universe was between about 800 million to 950 million years old."Until now, we had no idea what the black holes in these early galaxies were doing, or if they even existed," said Ezequiel Treister of the University of Hawaii, lead author of the study to appear Thursday in journal Nature. "Now we know they are there, and they are growing like gangbusters."The super-sized growth means that the black holes in the CDFS are less extreme versions of quasars -- very luminous, rare objects powered by material falling onto supermassive black holes. However, the sources in the CDFS are about a hundred times fainter and the black holes are about a thousand times less massive than the ones in quasars.The observations found that between 30 and 100 percent of the distant galaxies contain growing supermassive black holes. Extrapolating these results from the small observed field to the full sky, there are at least 30 million supermassive black holes in the early universe. This is a factor of 10,000 larger than the estimated number of quasars in the early universe."It appears we've found a whole new population of baby black holes," said co-author Kevin Schawinski of Yale University. "We think these babies will grow by a factor of about a hundred or a thousand, eventually becoming like the giant black holes we see today almost 13 billion years later."

BEIJING, Sep. 16 (Xinhuanet) -- Government incentives are important to pave a low-carbon road to economic growth, but companies that improve their industry models and technologies are the main players and also benefit receivers, noted officials and industry insiders at the Summer Davos forum held in Dalian on Sep 14."The most important thing is to have the right direction," said Gao Jifan, chairman and CEO of Trina Solar, a national leading solar panel manufacturer in China.According to Gao, new energy solutions such as solar power, is the "right direction" of future growth, although many deficiencies still exist today. "As long as we have the direction correct, we can succeed as last. But this also requires policies, technologies and investment," he said.Malini Mehra, founder and CEO of the Centre for Social Markets, a non-profit organization that promotes sustainability, said there are two ways in which the governments can support low-carbon businesses to continue along a "green" path."The first is to provide some means of recognizing their good work," she said. And the second is building a measuring system to "verify which company is actually doing well, not just talking about doing well".Preferential policies are only the foundation, said Gao. "We must have a good overall plan along with advanced technologies to bring value back to the investors."Gao envisions that most of the world’s families will have "zero-consumption" houses with energy supply and storage systems relying purely on solar power by 2020.Without grid limitations, the technology can be used everywhere in the world, especially in the less developed areas."The cost of solar technologies has been on the decline over the past few years because of policy incentives and innovations of companies around the world," said Gao.A solar panel producing one watt’s electricity cost in 2005, but now it is reduced to only .2 to .3, he explained."This is the result of technological innovations and large-scale manufacturing. And it makes us more confident to see the solar energy to become a major part of the energy system in the future."Being low-carbon also helps a company attract clients because it is the current fashion and customers are more likely to choose low-carbon products, noted Klaus Kleifeld, CEO of the US aluminum products maker Alcoa Inc."The generation that we recruit today has a very different social consciousness and standards," he said. "They want to see and only want to work for companies that are sustainable."

SAN FRANCISCO, Aug. 15 (Xinhua) -- Facebook and Yahoo on Monday started to test "six degrees of separation," an iconic social experiment in the 1960s that showed everyone is on average approximately six steps away from any other person on earth.The current Facebook-Yahoo "small world" experiment, based on more than 750 million active Facebook users, is expected to determine the social path length between two strangers.Anyone with a Facebook account can participate by going to smallworld.sandbox.yahoo.com and will be assigned a "target person. " The participant will be asked to select one of his or her Facebook friends, whom will be forwarded a message and then pass the message from friend to friend so that the participant will get a message to the "target person" in as few steps as possible.The study is intended as academic social research and will be published in peer-reviews scientific journal, Duncan Watts, Yahoo' s principal research scientist who is leading the experiment, told San Jose Mercury News.In the 1960s, American social psychologist Stanley Milgram and other researchers conducted several experiments to examine the average path length for social networks of people in the United States, suggesting that human society is a small world type network by around 5.5 people steps or about six people on average.It is now currently accepted that there were potential flaws in the so-called "small world experiment" because the conclusions were based on relatively small number of research samples.

CHENGDU, Sept. 3 (Xinhua) -- A list of this year's top 500 Chinese enterprises was unveiled in the city of Chengdu in southwest China's Sichuan Province on Saturday.The Sinopec Group was ranked first, with last year's revenues reaching 1.97 trillion yuan (307.81 billion U.S. dollars), followed by the China National Petroleum Corp. and State Grid Corp., whose revenues hit 1.72 trillion yuan and 1.53 trillion yuan last year, respectively.The rest of the top 10 was rounded out by the Industrial and Commercial Bank of China, China Mobile, China Railway Group, China Railway Construction Corp., China Construction Bank, China Life Insurance Co. and Agricultural Bank of China.The list is the 10th of its kind to be jointly released by the China Enterprise Confederation and the China Enterprise Directors Association. The threshold for entering the list was raised to 14.2 billion yuan in revenues, an increase over the 11.08-billion-yuan threshold used during the previous year.Revenues for China's top 500 companies rose 31.6 percent year-on-year to 36.31 trillion yuan in 2010, while their total assets increased by 18.4 percent to 108.1 trillion yuan, the two organizations said.The companies reported profits of 2.08 trillion yuan for last year, a rise of 38.67 percent from one year earlier.They paid 2.73 trillion yuan in taxes in 2010, accounting for 37.3 percent of the country's total tax revenues.

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.

来源：资阳报