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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."

PARIS, May 20 (Xinhua) -- Heavy-load launcher Ariane 5, carrying two communication satellites GSAT-8 and ST-2, lifted off at around 22:38 p.m. Paris time (GMT 2038) on Friday from Europe' s Spaceport in French Guiana.Built by Japan's Mitsubishi Electric Company, ST-2 will offer Ku-and C-band relay services across the Middle East, Central Asia, India and Southeast Asia to the ST-2 Satellite Ventures joint company of Singapore Telecommunications Ltd (SingTel) and Taiwan' s Chunghwa Telecom Company Ltd..With a weight around 5.1 tons at launch, ST-2 was separated first around 27 minutes after the lift-off. It has a designed life of 15 years and will function at 88 degree East.The lighter passenger GSAT-8, built by the Indian Space Research Organization (ISRO), will serve to augment India's Ku- band relay capabilities and offer aircraft navigation assistance over Indian airspace and adjoining areas with its two-channel GAGAN system.GSAT-8 was expected to be ejected off around 31 minutes into the flight and will be orbited at 55 degree East. Weighed about 3. 1 tons, it has a designed life span of at least 12 years.Arianespace started its 2011 busy year for heavy-lift Ariane 5 with the milestone launch of Europe's second Automated Transfer Vehicle (ATV) on February 16.The next launch of Ariane 5 planned to lift off two TV broadcast and telecommunications relay satellites: BSAT-3c/JCSAT- 110R for Japan's Broadcasting Satellite System Corporation (B-SAT) and SKY Perfect JSAT Corporation, and ASTRA 1N for Luxemburg-based SES company.

BEIJING, March 10 (Xinhuanet) -- Cigarette displays in shops will be banned and tobacco companies may also be forced to make their products in plain wrappers in an attempt to stop people from smoking, announced the UK government Thursday.The prominent displays and attractive packaging of tobacco have long provided shopkeepers with stable income, keeping addicts hooked and quitters tempted.However, the government's move that will begin as early as spring next year will keep cigarettes hidden away and make it just a tad more difficult for smokers to find their fix."Nearly all adult smokers started smoking before they turned 18 and every year, over 300,000 children under 16 try smoking," said Chief Medical Officer Sally Davies."Smoking is undeniably one of the biggest and most stubborn challenges in public health. Over eight million people in England still smoke and it causes more than 80,000 deaths each year," Health Secretary Andrew Lansley said in his statement on the new law.Now, this move has drawn predictable responses from both sides of the tobacco wars, with health groups cheering and retailers grumbling.The British Medical Association said it was "very pleased" with the announcement, citing research which it said showed that a display ban would play "a key role in discouraging children from smoking and also help smokers quit."On the other hand, industry groups and independent retailers complained it would burden them with the cost of refitting their stores and reduce their already narrow profit margins.And according to media interviews, many people kept skeptical about the real impact the move would have, especially on young smokers.

BEIJING, Feb. 24 (Xinhua) -- Chinese Premier Wen Jiabao attended the opening ceremony of the China-EU Year of Youth in Beijing on Wednesday, encouraging young people from China and the EU to build a brighter future for bilateral strategic partnerships.Joining over 500 young people from China and the EU in the Capital Museum in downtown Beijing, Wen said that the year-long youth exchange campaign was the first theme year between China and the EU since the establishment of diplomatic ties, and is also the largest-ever China-EU cultural exchange program."This has revealed that our relations will be more vibrant in the future and full of hopes," he added.China and the EU are in a vital period for deepening cooperation, Wen said, calling on young people from both sides to consider and explore ways to share opportunities, meet challenges and seek common development, which has benefits for China, the EU and the world.Wen hopes that young people from both sides would always be brave in pursuing innovation and the truth. He also encouraged them to learn from each other in a frank and open spirit, in a bid to jointly create a better future for China-EU ties.A video speech from European Commission President Jose Manuel Barosso was aired at the ceremony. He said that the Year of Youth offers an interactive platform for European and Chinese young people to enhance mutual understanding and friendship and also inject vitality to China-EU relations.Premier Wen and Barroso jointly initiated The China-EU Year of Youth during the 12th EU-China summit held in 2009.Along with the opening ceremony in Beijing, Chinese and European youth were immersed in two-day discussions on topics such as culture, education, volunteering, creativity and environmental protection starting on Tuesday."We had excellent discussions on possible cooperation projects, ranging from environmental protection, world heritage to art and intellectual property," said Pierre Arlaud, a member of an EU youth delegation that arrived in Beijing on Monday to participate in the opening ceremony."I can feel there is a strong will from both sides to deepen understanding and forge a stronger partnership," he added.The opening ceremony was the first in a series of exchange activities that will be held throughout the year in China and Europe. The events include cultural seminars, volunteer service conferences, youth summer camps and TV debates.The year-long program was co-hosted by the All-China Youth Federation and the European Commission. The initiative aims to promote intercultural dialogue and strengthen mutual understanding and friendship between young people in China and the EU, as well as encouraging them to support the development of China-EU relations.

BEIJING, Jan. 29 (Xinhua) -- Chinese State Councilor Dai Bingguo and U.S. National Security Advisor Tom Donilon on Saturday both spoke highly of Chinese President Hu Jintao's state visit to the United States earlier this month.During a phone conversation, Dai and Donilon agreed that China and the United States should make joint efforts to properly implement the consensus reached by leaders on both sides and cement the achievements made during Hu's visit, which was on Jan. 18-21.They also said that the two sides should maintain the current momentum in the development of bilateral ties and devote themselves to building a cooperative partnership based on mutual respect and mutual benefit.