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BEIJING, Sept. 6 (Xinhuanet) -- Scientists from Tufts University of the U.S. have created the world's smallest electrical motor in a single molecule.The finding was published in the journal Nature Nanotechnology on Monday.In the research, scientist successfully made a single molecule accept an electrical charge and rotate as fast as 120 revolutions per second."This is the first time that electrically-driven molecular motors have been demonstrated, despite a few theoretical proposals," said Charles H. Sykes, professor of chemistry at Tufts who led the team.The single molecule electric motor could lead to new types of electrical circuitry, giving hope for scientists to apply it in medicine and engineering, he said."The next thing to do is to couple it to other molecules, lining them up next to one another so they're like miniature cog-wheels, and then watch the rotation propagation down the chain," said Sykes.

BUDAPEST, June 25 (Xinhua) -- Visiting Chinese Premier Wen Jiabao made a five-point proposal here Saturday to enhance China's cooperation with countries in Central and Eastern Europe.When delivering a speech at the China-Central and East European Countries Economic and Trade Forum, Wen said China cherished its longstanding and deep friendship with the countries in the region."Over the past several decades, although the international situation and the domestic situations of both sides have undergone big changes, we have always enjoyed mutual respect, mutual trust, mutual understanding and mutual support," Wen said. Chinese Premier Wen Jiabao addresses the China-Central and Eastern European Countries Economic and Trade Forum in Budapest, Hungary, June 25, 2011.He said cooperation in various fields between the two sides had made tremendous progress, referring to the rapid growth of two-way trade, the burgeoning of mutual investment, the expansion of cooperation areas and the improvement of cooperation mechanisms.China encouraged its companies to "go global" and saw Central and Eastern Europe as a strategic priority, the Chinese leader said, adding that his current visit was "both a journey of friendship and a journey of cooperation."

CANBERRA, June 10 (Xinhua) -- Going to work when you are feeling sick can make you sicker in the long run, an expert told Australia's media on Friday.New Zealand sociologist Professor Kevin Dew from the Victoria University in Wellington, has assessed more than 40 papers about " presenteeism".He defined presenteeism as: "People that are turning up at work when they feel that they should be at home sick.""People feel compelled to go to work because someone else would have to take up the workload (and they have a) feeling of responsibility for not being able to care properly for patients (if they don't show up)," he told the Australia Associated Press on Friday.He said that evidence suggested people who go to work when they are sick can have long term negative effects on health and productivity.Evidence shows that presenteeism increases illness, including musculoskeletal pain, fatigue, depression, and serious coronary events. It also leads to exhaustion which, in turn, leads to more presenteeism.Prof. Dew said certain medical conditions like depression and migraine are also linked with presenteeism because they are not seen as legitimate reasons for absence.He has written an editorial in the latest issue of the British Medical Journal about his findings.

BEIJING, Sept. 25 (Xinhua) -- As China's economy has soared to the second place in the world, the country's scientific strength has also surged -- if only measured by the numbers.Chinese researchers published more than 1.2 million papers from 2006 to 2010 -- second only to the United States but well ahead of Britain, Germany and Japan, according to data recently published by Elsevier, a leading international scientific publisher and data provider. This figure represents a 14 percent increase over the period from 2005 to 2009.The number of published academic papers in science and technology is often seen as a gauge of national scientific prowess.But these impressive numbers mask an uncomfortable fact: most of these papers are of low quality or have little impact. Citation per article (CPA) measures the quality and impact of papers. China's CPA is 1.47, the lowest figure among the top 20 publishing countries, according to Elsevier's Scopus citation database.China's CPA dropped from 1.72 for the period from 2005 to 2009, and is now below emerging countries such as India and Brazil. Among papers lead-authored by Chinese researchers, most citations were by domestic peers and, in many cases, were self-citations."While quantity is an important indicator because it gives a sense of scientific capacity and the overall level of scientific activity in any particular field, citations are the primary indicator of overall scientific impact," said Daniel Calto, Director of SciVal Solutions at Elsevier North America.Calto attributed China's low CPA to a "dilution effect.""When the rise in the number of publications is so rapid, as it has been in China -- increasing quantity does not necessarily imply an overall increase in quality," said Calto.He noted the same pattern in a variety of rapidly emerging research countries such as India, Brazil, and earlier in places like the Republic of Korea."Chinese researchers are too obsessed with SCI (Science Citation Index), churning out too many articles of low quality," said Mu Rongping, Director-General of the Institute of Policy and Management at the Chinese Academy of Sciences, China's major think tank.SCI is one of the databases used by Chinese researchers to look-up their citation performance. The alternative, Scopus, provides a wider coverage worldwide."Chinese researchers from a wide range of areas and institutions are vying for publication, as it is a key criterion for academic appraisal in China, if not the only one. As a result, the growth of quality pales in comparison to that of quantity," said Mu, an expert on China's national science policy and competitiveness.On the other hand, China also falls behind the United States in multidisciplinary research, which is a core engine for scientific advance and research excellence.From 2006 to 2010, China published 1,229,706 papers while the United States churned out 2,082,733. According to a new metric introduced by Elsevier's Spotlight research assessment solution, China generated 885 competencies while the United States had 1,817.In other words, China's total research output is more than half that of the United States, while the number of competencies showing China's strength in multidisciplinary research is less than half that of the United States.Cong Cao, an expert on China's science and technology, put it more bluntly in an article he wrote: "When the paper bubble bursts, which will happen sooner or later, one may find that the real situation of scientific research in China probably is not that rosy."China has been investing heavily in scientific research and technological development in recent years to strengthen its innovative capacity, The proportion of GDP spent on R&D grew from 0.9 percent in 2000 to 1.4 percent in 2007, according to the World Bank.An IMF forecast in 2010 says China now ranks second globally in R&D spending. The IMF calculates China's R&D expenditure at 150 billion U.S. dollars when based on Purchasing Power Parity, a widely used economic concept that attempts to equalize differences in standard of living among countries.By this measure, China surpassed Japan in R&D spending in 2010.Many see China's huge investment in R&D as the momentum behind the country's explosive increase in research papers."Getting published is, in some ways, an improvement over being unable to get published," Mu said. "But the problem is, if the papers continue to be of low quality for a long time, it will be a waste of resources."In China, academic papers play a central role in the academic appraisal system, which is closely related to degrees and job promotions.While acknowledging the importance of academic papers in research, Mu believes a more balanced appraisal system should be adopted. "This is a problem with science management. If we put too much focus on the quantity of research papers, we leave the job of appraisal to journal editors."In China, the avid pursuit of publishing sometimes gives rise to scientific fraud. In the most high-profile case in recent years, two lecturers from central China's Jinggangshan University were sacked in 2010 after a journal that published their work admitted 70 papers they wrote over two years had been falsified."This is one of the worst cases. These unethical people not only deceived people to further their academic reputations, they also led academic research on the wrong path, which is a waste of resources," Mu said.A study done by researchers at Wuhan University in 2010 says more than 100 million U.S. dollars changes hands in China every year for ghost-written academic papers. The market in buying and selling scientific papers has grown five-fold in the past three years.The study says Chinese academics and students often buy and sell scientific papers to swell publication lists and many of the purported authors never write the papers they sign. Some master's or doctoral students are making a living by churning out papers for others. Others mass-produce scientific papers in order to get monetary rewards from their institutions.A 2009 survey by the China Association for Science and Technology (CAST) of 30,078 people doing science-related work shows that nearly one-third of respondents attributed fraud to the current system that evaluates researchers' academic performance largely on the basis of how many papers they write and publish.Despite rampant fraud, China will continue to inject huge money into science. According to the latest national science guideline, which was issued in 2006 by the State Council, the investment in R&D will account for 2.5 percent of GDP in 2020."If China achieves its stated goal of investing 2.5 percent of its GDP in R&D in 2020, and sustains its very fast economic growth over the next decade, it would quite likely pass the U.S. in terms of total R&D investment sometime in the late 2010s," said Calto, adding that it is also quite likely that at some point China will churn out more papers than the United States.According to Calto, China does mostly applied research, which helps drive manufacturing and economic growth, while basic research only accounts for 6 percent, compared with about 35 percent in Germany, Britain, and the United States, and 16 percent in Japan."In the long term, in order to really achieve dominance in any scientific area, I think it will be necessary to put significant financial resources into fundamental basic research -- these are the theoretical areas that can drive the highest level of innovation," Calto said.

BEIJING, Aug. 24 (Xinhuanet)-- A new study shows that a diet rich in cholesterol-friendly foods, such as soy products and tree nuts, can decrease LDL (bad) cholesterol significantly, according to media reports on Tuesday.The study, published in the Journal of the American Medical Association, found that people who ate a healthy diet filled with cholesterol-lowering foods experienced a 13 percent decrease in their LDL cholesterol levels.For patients with high levels of so-called bad cholesterol, doctors usually have two prescriptions: cholesterol-lowering statin drugs and a diet that cuts out foods high in saturated fat, such as ice cream, red meat and butter.But the new study found that when it comes to lowering artery-clogging cholesterol, what you eat may be more important than what you don't eat.David Jenkins of St. Michael's Hospital and the University created the "portfolio diet," which includes regular consumption of tree nuts and high amounts of fiber from oats, barley and vegetables. The diet, which replaces butter with plant sterol-enriched margarine and substitute soy-based products for meat, allows maximum benefit in lowering cholesterol and preventing heart disease. "The study highlighted the power of food to lower risk for cardiovascular disease: What you do eat and what you don't eat are both important," said Dr. Jane Klauer, a New York internist specializing in metabolism and nutrition.A high overall cholesterol level makes a person nearly twice as likely to suffer a heart attack or stroke as someone whose total cholesterol falls into a healthy range.

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