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OTTAWA, Sept. 29 (Xinhua) -- Climate change could cost Canada billions of dollars a year by the end of this decade, a government funded study group announced Thursday.The National Round Table on the Environment and the Economy said the cost of climate change for Canada could start at roughly 5 billion Canadian dollars per year in 2020 and increase to between 21 billion and 43 billion per year by 2050. Those costs would come from shoreline damage, public health problems, and disruptions to the economy.It also predicted a slight increase in deaths in major cities from heat and air pollution.The round table researchers estimated the cost of climate change is expected to be roughly 0.8 percent to 1.0 percent of GDP -- or 43 billion Canadian dollars a year -- by 2050, if the problem is allowed to worsen.But the report did not address possible benefits, such as reduced demand for hea

PHNOM PENH, Aug. 17 (Xinhua) -- The critically endangered Irrawaddy dolphin population in the Mekong River numbers just 85, World Wildlife Fund (WWF) new research revealed on Wednesday.Calf survival was found to be very low, leading researchers to conclude that the small population is declining and at high risk of extinction, said the Fund's statement sent to Xinhua News Agency on Wednesday.According to Li Lifeng, Director of WWF's Freshwater Program, the research is based on photographic identification of dolphins through individually unique features of their dorsal fins. "Most of the dolphins can be identified, and we use that information to estimate the population size," he said.Although this population estimate is slightly higher than the previous estimate, the researchers were quick to note that the population had not increased over the last few years."With a larger dataset and recent analytical advances, previously unidentifiable dolphins which had few marks on their dorsal fins have been included," he added.However, surveys conducted from 2007 to 2010 show the population slowly declining."Evidence is strong that very few young animals survive to adulthood, as older dolphins die off and are not replaced," he explained."Pressures of gill net entanglement and high calf mortality we are really worried for the future of dolphins," Li said.However, Touch Seang Tana, chairman of Cambodia's Commission for Conversation and Development of the Mekong River Dolphins Eco- tourism Zone, rejected the WWF's finding, saying that last year, 4 dolphins were killed by fishing nets, but up to 7 newborn dolphin babies were found.He estimated that the total population of Mekong dolphins in the north-eastern provinces of Kratie and Stung Treng is between 155 and 177 now, up from just 100 in 2006.The Mekong River Irrawaddy dolphin has been listed as critically endangered on the World Conservation Union Red List of Threatened Species since 2004.

LOS ANGELES, July 28 (Xinhua) -- Mainly due to rampant obesity, Americans' life expectancy is one-and-a-half-year shorter than that of Western Europeans on the average, according to a new study published on Thursday.But 40 years ago, Americans could expect to live slightly longer than Europeans, said the study jointly conducted by researchers from University of Southern California (USC), the Harvard School of Public Health and the RAND Corp., a non-profit think tank.In addition to Western Europeans, Americans also die younger than the residents of most other developed nations, according to the study appearing in the July issue of Social Science & Medicine.The life-expectancy disparity, which begins around the age of 50, stems from higher levels of middle-age obesity and obesity-related chronic diseases, such as hypertension and diabetes, said the study.In the first half of the last century, average life expectancy increased by saving more babies, said author Dana Goldman, director of the Schaeffer Center for Health Policy and Economics at the USC."But now it is reduction in mortality among the elderly, rather than the young, that propels increases in life expectancy," he said. "The question is whether 'being American' is an independent mortality risk factor."If 50-year-old U.S. adults could be as healthy as Europeans, it could save Medicare and Medicaid 632 billion dollars by 2050, the study said.Though the transition to better health initially raises expenditures, the researchers estimate that by 2050 healthcare savings from health improvements among the middle age could total more than 1.1 trillion dollars."The international life expectancy gap appears much easier to explain than gaps within countries: there is no American-specific effect on longevity beyond differences in disease at age 50," said Darius Lakdawalla, an associate professor in the USC School of Policy, Planning and Development.

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."

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