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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.

BEIJING, Sept. 2 (Xinhuanet) -- Insomnia costs average U.S. worker 11.3 days, or 2,280 dollars, in lost productivity each year, according to a new study published in journal Sleep.The total cost to the nation is 63.2 billion dollars annually, the study said.Researchers analyzed information about sleep habits and work performance from 7,428 workers taking part in Harvard Medical School's American Insomnia Study survey in 2008-09.As a result, 23.2 percent of the participants suffered insomnia, characterized by a hard time falling or staying asleep.Moreover, insomnia rates were 19.9 percent for those with less than a high school education and 21.5 percent for college graduates."We were shocked by the enormous impact insomnia has on the average person's life," said Ronald C. Kessler, a lead author and a psychiatric epidemiologist at Harvard Medical School."It's an underappreciated problem. Americans are not missing work because of insomnia. They are still going to their jobs but accomplishing less because they're tired," Kessler noted.Employers usually ignore the consequences of insomnia because it's not considered an illness resulting in workers' absenteeism.But the high cost of lost sleep identified in this study indicates that employers need to take it more seriously.

DUBLIN, June 27 (Xinhua) -- The Irish government is aiming to increase internet literacy among older people with the launch of a 1.6 million euro training program, according to a cabinet minister on Monday.The goal of the scheme is to provide basic internet skills to 30,000 elderly people across the country who are less likely engage with the internet themselves.The announcement was made by Irish communications minister Pat Rabbitte at a new computer training facility run by Age Action Ireland, an Irish charity which promotes positive aging and better policies and services for older people.The Irish minister detailed how the training program will help those involved."This scheme will enable thousands of people throughout Ireland, people otherwise likely to be left behind in the knowledge society, to acquire the basic practical know-how to improve their digital skills. In particular this will help older people, those with disabilities, the unemployed and other key target groups. They will learn to use the internet, emails and how to conduct simple on-line transactions," he said."Previous schemes show that learning such basic skills helps people in many ways, giving them new communication options, new opportunities to save money, as well as better access to a wide range of on-line services," he added."We have also seen how such new skills and the opportunities that result from them improve people's confidence and wellbeing. More widespread participation in the knowledge society is a win- win outcome with advantages for citizens, government and the wider economy."

coastline in the U.S. State of California sampled by the state water board harbored fish with mercury in such high concentrations that they shouldn't be eaten by young women and children, a newly released survey has found.Fourteen percent of locations had similarly elevated levels of PCBs, according to the survey published by The Los Angeles Times on Sunday.The most elevated concentrations of mercury and PCBs were found in San Francisco Bay and San Diego Bay, said the survey funded by the state water board.The findings, part of a two-year inquiry that is the largest statewide survey of contaminants in sport fish along the California coast, examined more than 2,000 fish from three dozen species gathered in 2009 from waters near Los Angeles, San Francisco and San Diego, the paper said.The survey highlights the health problem of lingering mercury, a poisonous metal that is found in fish globally, and of PCBs, toxic chemicals the United States banned in the 1970s, the report said.Both substances continue to pose a risk to people who eat fish caught along the California coast because they can lead to nervous system damage and developmental problems in children and can cause cancer, liver damage and reproductive harm, the report quoted researchers as saying."Unfortunately, we're not seeing many areas that are totally clean," said Jay Davis, a senior scientist for the San Francisco Estuary Institute and lead author of the study. But a catalog of where and in what fish the substances abound should help anglers make better choices, Davis said. "With good information, people can reduce their exposure significantly."Sharks had some of the highest levels of mercury because of their unusual tendency to accumulate contaminants in their flesh, while chub mackerel had the lowest levels of contamination, according to the survey.The survey results were used in part to help craft new fish consumption guidelines issued earlier this week for anglers in San Francisco Bay, the first update there by state health officials in 17 years. The advisory identifies shiner perch and other surf perches as unsafe to eat in any quantity and warns young women and children not to eat white sturgeon, striped bass and sharks caught in the bay, The Times said.The buildup of metals and other chemicals in fish is such a problem along the Southern California coast that health officials two years ago expanded the number of fish species on the "do not eat" list from one to five because of high levels of PCBs, mercury and the banned pesticide DDT, the report noted.

LOS ANGELES, July 18 (Xinhua) -- At least 70 genetic mutations may be involved in the formation of colon cancer, far more than scientists previously thought, a new study suggests.The study by researchers at University of Texas (UT) Southwestern Medical Center contradicts previous thinking that only a few mutated genes may play a role in the development of colon cancer."The ways we've been treating patients up to now is to just go after one target when we should be going after three to four different pathways simultaneously," said Dr. Jerry W. Shay, vice chairman and professor of cell biology at UT Southwestern.The new study identified 65 candidate genes and at least five passenger genes whose mutations play significant roles in cancer development. Inactivating the function of any of these tumor- suppressing genes led to a key step in cancer development called anchorage-independent growth, meaning cells piled up on top of each other rather than aligning neatly.According to previous studies, there were 151 candidate genes and that mutations in just eight to 15 of them would lead to cancer. There were 700 other genes classified as passenger genes whose mutations were incidental to cancer growth.Current cancer treatments target just one or two known cancer- driver genes. While patients may get transient tumor burden reduction, almost universally tumor growth returns."Those numbers are dead wrong," Dr. Shay said, suggesting a new approach to colon cancer treatments targeting multiple genes and pathways simultaneously.The next step is further research to classify more accurately which genes drive cancer and which are merely passengers, the researchers said.Study findings were published in the July 2011 Cancer Research (Priority Reports).

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