南昌治疗失眠方法(南昌那里有治躁狂) (今日更新中)

WASHINGTON, May 2 (Xinhua) -- Rice originated in China, a team of U.S. genome researchers has concluded in a study tracing back thousands of years of evolutionary history through large-scale gene re-sequencing.Their findings, which appear Monday in the latest issue of the Proceedings of the National Academy of Sciences (PNAS), indicate that domesticated rice may have first appeared as far back as approximately 9,000 years ago in the Yangtze Valley of China. Previous research suggested domesticated rice may have two points of origin -- India as well as China.Asian rice, Oryza sativa, is one of world's oldest crop species. It is also a very diverse crop, with tens of thousands of varieties known throughout the world. Two major subspecies of rice -- japonica and indica -- represent most of the world's varieties. Sushi rice, for example, is a type of japonica, while most of the long-grain rice in risottos are indica.Because rice is so diverse, its origins have been the subject of scientific debate. One theory -- a single-origin model -- suggests that indica and japonica were domesticated once from the wild rice O. rufipogon.Another -- a multiple-origin model -- proposes that these two major rice types were domesticated separately and in different parts of Asia. The multiple-origin model has gained currency in recent years as biologists have observed significant genetic differences between indica and japonica, and several studies examining the evolutionary relationships among rice varieties supported more than domestication in both India and China.In the PNAS study, the researchers re-assessed the evolutionary history, or phylogeny, of domesticated rice using previously published datasets, some of which have been used to argue that indica and japonica rice have separate origins. Using more modern computer algorithms, however, the researchers concluded these two species have the same origin because they have a closer genetic relationship to each other than to any wild rice species found in either India or China.In addition, the study's authors examined the phylogeny of domesticated rice by re-sequencing 630 gene fragments on selected chromosomes from a diverse set of wild and domesticated rice varieties. Using new modeling techniques, which had previously been used to look at genomic data in human evolution, their results showed that the gene sequence data was more consistent with a single origin of rice.In the study, the investigators also used a "molecular clock" of rice genes to see when rice evolved. Depending on how the researchers calibrated their clock, they pinpointed the origin of rice at possibly 8,200 years ago, while japonica and indica split apart from each other about 3,900 years ago. The study's authors pointed out that these molecular dates were consistent with archaeological studies.Archaeologists have uncovered evidence in the last decade for rice domestication in the Yangtze Valley beginning approximately 8, 000 to 9,000 years ago while domestication of rice in the India's Ganges region was around about 4,000 years ago."As rice was brought in from China to India by traders and migrant farmers, it likely hybridized extensively with local wild rice," explained New York University biologist Michael Purugganan, one of the study's co-authors. "So domesticated rice that we may have once thought originated in India actually has its beginnings in China."

BEIJING, May 16 (Xinhuanet) -- NASA has readied the space shuttle Endeavour for its liftoff set for Monday, media reported Monday.Good weather looks 70 percent likely for Monday's scheduled launch of Endeavour, the next-to-last U.S. space shuttle mission as NASA develops a new generation of craft for longer voyages."The updated forecast Sunday for Monday's launch of the shuttle Endeavour remains unchanged with a 70 percent chance of good weather," said NASA spokesman Allard Beutel.The space shuttle Endeavour STS-134 sits on launch pad 39A after the rollback of the Rotating Service Structure at the Kennedy Space Center in Cape Canaveral, Florida May 15, 2011.Liftoff is set for 8:56 a.m. EDT (1256 GMT) from the Kennedy Space Center for the trip to the International Space Station after the U.S. space agency repaired a technical glitch that canceled last month's launch attempt.The initial April 29 launch attempt was scrubbed hours before liftoff when technicians discovered a power failure in a heating line that served to prevent fuel from freezing in orbit.The six-member crew of astronauts including five Americans and one Italian, Roberto Vittori, will deliver a potent physics experiment to probe the origins of the universe during the mission, which will include four spacewalks.The 16-day mission is intended to help get the space station ready for operations after the shuttle fleet is retired. The 135th and final shuttle launch is scheduled for early- to mid-July aboard Atlantis.

GENEVA, May 3 (Xinhua) -- Roughly half to three quarters of adults aged between 18 to 65 years have had headache in the last year, a prevalent problem that went under-treated, the Geneva based World Health Organization (WHO) said in a report issued Tuesday.The report, named "Of Headache Disorders and Resources in the World 2011," regarded headache disorders as one of the most prevalent disorders of mankind.WHO estimated over 10 percent of the adult population suffered from migraine, and 1.7 to 4 percent of them were troubled frequently by headache on 15 or more days every month.Among all cases studied, the report said, on average only 10 percent were treated by neurologists, and the rates were even lower in Africa and South-East Asia.Three types of headache disorders were underlined as the most frequently seen, including migraine, tension-type headache and that caused by medication-overuse.The report concluded that given the very high indirect costs of headache, investment in health care related to headache treatment might be overall cost-saving to society.

SAN FRANCISCO, April 28 (Xinhua) -- Cisco Systems Inc., world's largest maker of computer-networking equipment, on Thursday brought up an early retirement offer to its employees in the United States and Canada, in a move to cut costs and restructure the company.The voluntary plan applies to employees who are at least 50 years old and have a combined age and years of service at Cisco for at least 60 as of July 8, the company said in a memo sent to employees."Cisco employs a variety of different methods to control costs and align investment dollars, and offering this voluntary early retirement program to those eligible employees in the U.S. and Canada is part of our ongoing commitment to responsible business management," the company said in a statement.Cisco gave no details on the costs it would save and the number of employees eligible for the plan.Earlier this month, Cisco CEO John Chambers warned that "tough decisions" would be made to preserve profitability as government budget pressure has been costing the company orders and slowing its sales growth.On April 12, Cisco announced to shut down its Flip Video camcorder business to restructure its business and support its key priorities.

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