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WASHINGTON, Aug. 11 (Xinhua) -- The unique fossils of an adult plesiosaur and its unborn baby may provide the first evidence that these ancient animals gave live birth like mammals, according to a new study to be published Friday in the journal Science.The 78-million-year-old, 15.4-foot-long (4.7-meter-long) adult specimen is a Polycotylus latippinus, one of the giant, carnivorous, four-flippered reptiles that lived during the Mesozoic Era.Dr. Robin O'Keefe of Marshall University in West Virginia and Dr. Luis Chiappe, Dinosaur Institute director of the Natural History Museum in Los Angeles County, have determined that it is the fossil of an embryonic marine reptile contained within the fossil of its mother.The embryonic skeleton contained within shows much of the developing body, including ribs, 20 vertebrae, shoulders, hips, and paddle bones.O'Keefe and Chiappe have also determined that plesiosaurs were unique among aquatic reptiles in giving birth to a single, large offspring, and that they may have lived in social groups and engaged in parental care.Although live birth has been documented in several other groups of Mesozoic aquatic reptiles, no previous evidence of it has been found in the important order of plesiosaurs."Scientists have long known that the bodies of plesiosaurs were not well suited to climbing onto land and laying eggs in a nest," O'Keefe said."So the lack of evidence of live birth in plesiosaurs has been puzzling. This fossil documents live birth in plesiosaurs for the first time, and so finally resolves this mystery."

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."

SAN FRANCISCO, Aug. 22 (Xinhua) -- Hewlett-Packard's tablet TouchPad has become the hottest consumer electronics device on Monday after HP launched a fire sale for the discontinued product line over the weekend."It was like a stampede and they went quick," a Best Buy employee in San Diego told technology news website Betanews, describing the line waiting to buy TouchPad. He said the discontinued tablet was sold out five minutes after the store opened.The device is also getting snatched up at a lighting speed online and increasingly difficult to find.The TouchPad is no longer listed on Bestbuy.com in the United States, which last week was reportedly sitting on 270,000 unsold TouchPads and was hoping HP would buy them back.On Amazon, TouchPad tops the world's largest online retailer's electronics sales list, beating out the electronic reader Kindle and iPod touch.Last Thursday, HP announced that it will completely shut down its webOS operations, specifically the TouchPad tablet and webOS phones.The 16 GB TouchPad currently is only 99.99 U.S. dollars, compared to the original price of 399 dollars. The 32 GB model, which used to be 485.99 dollars, is now priced at 149.99 dollars.

WASHINGTON, Aug. 4 (Xinhua) -- Researchers have found a way to turn mouse embryonic stem cells into sperm and this finding opens up new avenues for infertility research and treatment, according to a study published Thursday in the online edition of journal Cell,A Kyoto University team coaxed mouse embryonic stem cells into sperm precursors, called primordial germ cells (PGCs), and shown that these cells can give rise to healthy sperm. The researchers say that such in vitro reconstitution of germ cell development represents one of the most fundamental challenges in biology.When transplanted into mice that were unable to produce sperm normally, the stem cell derived PGCs produced normal-looking sperm, which were then used to successfully fertilize eggs. These fertilized eggs, when transplanted into a recipient mother, produced healthy offspring that grew into fertile male and female adult mice. The same procedure could produce fertile offspring from induced pluripotent stem cells that are often derived from adult skin cells."Continued investigations aimed at in vitro reconstitution of germ cell development, including the induction of female primordial germ cell-like cells and their descendants, will be crucial for a more comprehensive understanding of germ cell biology in general, as well as for the advancement of reproductive technology and medicine," the researchers wrote.

LOS ANGELES, July 5 (Xinhua) -- NASA's Juno spacecraft is 30 days away before its first launch window opens, the Jet Propulsion Laboratory (JPL) announced on Tuesday."One month from today, our first launch window opens at 11:34 a. m. EDT (8:34 a.m. PDT) and lasts 69 minutes," said Jan Chodas, Juno project manager from NASA's JPL in Pasadena, Los Angeles."Our primary launch period is 22 days long, and so if weather or other issues come up on Aug. 5, we have 21 more days to get Juno flying. Once we get Juno into space, it's a five-year cruise to Jupiter.""The launch window is the length of time allotted every day for an attempt to launch the spacecraft," said Chodas. "The launch period is the period of time in days when everything is in the right place to get your mission off to the right start."For a mission like Juno, getting everything in the right place includes considering the size of the rocket and spacecraft, where our home planet -- and in particular Juno's launch pad -- is pointed at any moment, and its location in space relative to other celestial objects like Juno's final target, Jupiter.Juno is scheduled to launch aboard a United Launch Alliance Atlas V rocket from pad 41-C at the Cape Canaveral Air Force Station, Florida.The solar-powered spacecraft will orbit Jupiter's poles 33 times to find out more about the gas giant's origins, structure, atmosphere and magnetosphere and investigate the existence of a solid planetary core.JPL manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio.The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Alaska. Lockheed Martin Space Systems, Denver, built the spacecraft.

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