南昌市治疗幻幻症哪家医院比较好(南昌治疗双相情感障碍中医) (今日更新中)

BEIJING, July 27 (Xinhuanet) -- Amazon.com’s e-book reader Kindle 3G with special offers is now the company’s top-selling e-book device, according to media reports on Wednesday.Amazon revealed in its quarterly earnings report that the ad-supported version costs 139 U.S. dollars,  50 dollars cheaper than the comparable Kindle 3G, and costs the same as a Kindle with Wi-Fi connectivity. Many believe Kindle is the most popular dedicated e-book device on the market today.The advertisements will appear only in screensavers (which appear when the reader is in an idle state) and at the bottom of the home screen, so they don’t interrupt readers.“Since AT&T agreed to sponsor screensavers, Kindle 3G with Special Offers is now our bestselling Kindle device,” Amazon’s press release said.Having zoomed past the earlier Sony Reader, and kicked off a wave of competition including the Barnes & Noble Nook and the Kobo E-Reader, Kindle is believed the most popular dedicated e-book device on the market today.

WASHINGTON, Sept. 15 (Xinhua) -- A team of researchers has discovered a planet that orbits around a pair of stars, the U.S. space agency NASA announced Thursday.This is the first instance of astronomers finding direct evidence of a so-called circumbinary planet. A few other planets have been suspected of orbiting around both members of a dual-star system, but the transits of the circumbinary planet have never been detected previously.The team, led by Laurance Doyle of the SETI Institute in California, used photometric data from the NASA Kepler space telescope, which monitors the brightness of 155,000 stars.NASA's Kepler mission has discovered a world where two suns set over the horizon instead of just one. The planet, called Kepler-16b, is the most "Tatooine-like" planet yet found in our galaxy. Tatooine is the name of Luke Skywalker's home world in the science fiction movie Star Wars. In this case, the planet it not thought to be habitable. It is a cold world, with a gaseous surface, but like Tatooine, it circles two stars.They found the binary star system by detecting a system where the stars eclipsed each other from the perspective of the Kepler spacecraft. These stars have two eclipses: A primary eclipse when the larger star is partially blocked by the smaller star and a secondary eclipse where the smaller star is fully blocked by the larger star.But the researchers also noticed other times when the brightness of the two stars dropped, even when they were not in an eclipse position. This pattern suggested that there was likely a third object involved. The fact that these so-called tertiary and quaternary eclipses recurred after varying intervals of time, and were of different depths, indicated that the stars were in different positions in their orbit at each instance. This result showed that the tertiary and quaternary eclipses were being caused by something circling both stars, and not an object circling one or the other star.Measurements of the variations in the timing of all four types of eclipses, resulting from the mutual gravitational interactions of the two stars and the third body, demonstrated that the third object was, indeed, a planet. Their work indicates that the planet is less massive than Jupiter, possibly comparable in mass to Saturn, and that the larger of the two binary stars is smaller than our Sun.Their findings will be published Friday in Science."This discovery confirms a new class of planetary systems that could harbor life," Kepler principal investigator William Borucki said in a statement. "Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars. This milestone discovery confirms a theory that scientists have had for decades but could not prove until now."

WASHINGTON, May 30 (Xinhua) -- After nearly 12 days together in orbit, U.S. space shuttle Endeavour undocked from the International Space Station on Sunday night, NASA announced on Monday.According to NASA, the undocking took place at 11:55 p.m. EDT ( 0355 GMT Monday) as the spacecraft sailed 215 miles (346 km) above Bolivia.Pilot Greg Johnson, at the aft flight deck controls, flew Endeavour in a circle around the station at distances of about 450 to 650 feet. Crew members took still and video images of the station.The Space Shuttle Endeavour is seen as it departs the International Space Station after undocking in this image from NASA TV May 29, 2011.As Johnson was about to begin the flyaround, Commander Mark Kelly radioed mission control that he could see the two-billion-U. S.-dollar Alpha Magnetic Spectrometer (AMS) particle physics detector Endeavour had brought to orbit. "It's a new day for science on the space station," he said to mission control.The AMS will be left at the space station to scour the universe for clues about dark matter and antimatter. Endeavour is scheduled to land at the Kennedy Space Center at 2:35 a.m. (0635 GMT) on Wednesday.During their stay at the space station, the Endeavour crew conducted four spacewalks to complete construction of the U.S. side of the 100-billion-dollar outpost, a project of 16 nations that has been being assembled in orbit since 1998.They also brought up a logistics carrier with spare parts and performed some maintenance and installation work during the four spacewalks, the last to be carried out by an American shuttle crew.NASA plans to decommission Endeavour, its youngest shuttle with 25 voyages, and send it to a museum in Los Angeles for display.NASA's 30-year-old shuttle program is ending due to high operating costs. The Obama administration wants to spur private companies to get into the space taxi business, freeing NASA to focus on deep space exploration and new technology development.When the U.S. space shuttle program officially ends later this year, the Russian space program's Soyuz capsule will be the only method for transporting astronauts to and from the space station.

WASHINGTON, Sept. 14 (Xinhua) -- Controlling diabetes may someday involve mining stem cells from the lining of the uterus, Yale School of Medicine researchers report in a new study published Wednesday in the journal Molecular Therapy. The team treated diabetes in mice by converting cells from the uterine lining into insulin-producing cells.The endometrium or uterine lining, is a source of adult stem cells. These cells generate uterine tissue each month as part of the menstrual cycle. Like other stem cells, however, they can divide to form other kinds of cells.Led by Yale Professor Hugh Taylor, the researchers bathed endometrial stem cells in cultures containing special nutrients and growth factors. Responding to these substances, the endometrial stem cells adopted the characteristics of beta cells in the pancreas that produce insulin. Over the course of a three- week incubation process, the endometrial stem cells took on the shape of beta cells and began to make proteins typically made by beta cells. Some of these cells also produced insulin.After a meal, the body breaks food down into components like the sugar glucose, which then circulates in the blood. In response, beta cells release insulin, which allows the body's cells to take in the circulating glucose. In this study, Taylor and his team exposed the mature stem cells to glucose and found that, like typical beta cells, the cultured cells responded by producing insulin. The team then injected diabetic mice with the mature, insulin-making stem cells. The mice had few working beta cells and very high levels of blood glucose.Mice that did not receive the stem cell therapy continued having high blood sugar levels, developed cataracts and were lethargic. In contrast, mice that received the cell therapy were active and did not develop cataracts, but the animals' blood sugar levels remained higher than normal.The Yale team's findings suggest that endometrial stem cells could be used to develop insulin-producing islet cells, which are found in the pancreas. These islet cells could then be used to advance the study of islet cell transplantation to treat people with diabetes.Taylor said in a statement that the next step in the research will be to verify how long this treatment remains effective.

ROME, Sept. 27 (Xinhua) -- The 30th general assembly of the International Council for Science (ICSU) kicked off here on Tuesday to address key global challenges, featuring over 275 scientists and experts from all over the world.The goal of the four-day event, hosted for the first time in Rome by the National Research Center (CNR) as Italy's scientific member at ICSU, is to discuss how science can contribute to boosting sustainable development, fighting climate change, increasing well-being and health in the changing urban environment and tackling the side-effects of progress.At the official opening ceremony, CNR president Francesco Profumo stressed that scientific research was the key to solving all current crises."It's during times of crises that inventions, great strategies and discoveries are made," he said quoting Albert Einstein."Global cooperation is crucial in addressing society's needs. In the wake of the negative economic outlook we are witnessing research and technological transfer can turn into efficient instruments to guide countries towards a solid development giving us the tools to tackle with lucidity the great obstacles we face," observed Profumo.Appealing to both private and public institutions, Profumo thus urged to boost strategic partnerships between universities, governments and research centres."We must create a network of knowledge-sharing together with enterprises in order to multiply and better implement growth and well-being opportunities. But in order to do so concrete political decisions must be undertaken and financial resources are needed," he added.

来源：资阳报