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WASHINGTON, Jan. 2 (Xinhua) -- A systematic review of previous studies suggests that there may be a positive connection between physical activity and children's academic performance, according to a report published Monday in the Archives of Pediatrics & Adolescent Medicine.A group of scientists at the Vrije Universiteit (Free University) Medical Center in the Netherlands reviewed evidence on the relationship between physical activity and academic performance because of concerns that pressure to improve test scores may often mean more instructional time for classroom subjects with less time for physical activity.The authors identified 10 observational and four interventional studies for review, 12 of which were done in the United States, one in Canada and one in South Africa. Sample sizes ranged from 53 to about 12,000 participants between the ages of eight years and 18 years old. Follow-up varied from eight weeks to more than five years."According to the best-evidence synthesis, we found strong evidence of a significant positive relationship between physical activity and academic performance. The findings of one high-quality intervention study and one high-quality observational study suggest that being more physically active is positively related to improved academic performance in children," the report said.Background information in the article suggests that exercise may help cognition by increasing blood and oxygen flow to the brain, increasing levels of norepinephrine and endorphin to decrease stress and improve mood, and increasing growth factors that help create new nerve cells and support synaptic plasticity."More high-quality studies are needed on the dose-response relationship between physical activity and academic performance and on the explanatory mechanisms, using reliable and valid measurement instruments to assess this relationship accurately," the report concluded.

XUZHOU, Dec. 13 (Xinhua) -- Three critically injured students died in hospital in east China's Jiangsu Province early Tuesday, the government said, bringing the toll of Monday's school bus overturn to 15.The accident was the third serious one involving a school bus in China in less than a month.At least eight other children are still hospitalized, a government spokesman of Fengxian County said, without elaborating on the conditions of their injuries.A bus carrying 29 students on their way home fell into a roadside ditch when the driver tried to avoid a pedicab in the rural areas of Fengxian at 5:50 p.m. on Monday.The bus belonged to a primary school in Shouxian township. The government said the bus, designed with a maximum carrying capacity of 52 persons, was not overloaded.Also on Monday, another school bus carrying 59 students was badly hit by a truck in the city of Foshan, Guangdong Province, injuring 37 students, Guangzhou Daily reported Tuesday. Seven of the injured had been hospitalized.The accidents occurred only a day after the State Council moved to strengthen school bus safety after a deadly crash killed 19 pupils about a month ago.The nine-seat school bus illegally carrying 64 people collided head-on with a coal truck in northwestern Gansu Province on Nov. 16, killing 19 preschoolers and two adults, and injuring 43 others.Schools are few in numbers in the vast and sparsely populated rural areas of China. School bus is a relatively new thing in some rural areas as for decades children from the countryside had been trekking on rugged countryroads on foot to attend school. But rural school buses varied on quality and safety.Chinese Premier Wen Jiabao had called on government departments to "rapidly" draft safety regulations and standards for school buses while further improving the design, production and distribution of the vehicles.

WASHINGTON, Oct. 9 (Xinhua) -- U.S. researchers have found a way to block, in an animal model, the damaging inflammation that contributes to many disease conditions. In their report receiving early online publication Sunday in Nature Biotechnology, researchers describe using small interfering RNA technology to silence the biochemical signals that attract a particular group of inflammatory cells to areas of tissue damage."The white blood cells known as monocytes play a critical role in the early stages of the immune response," says Matthias Nahrendorf, of the Massachusetts General Hospital (MGH) Center for Systems Biology, the paper's senior author. "We now know there are two subsets of monocytes -- an inflammatory subset that defends against pathogens and a reparative subset that supports healing. But if the inflammatory response is excessive, it can block the healing process and exacerbate conditions such as heart disease and cancer."Cells damaged by injury or disease release a cocktail of chemicals called cytokines that attract immune cells to the site of the damage. Inflammatory monocytes are guided to sites of tissue injury by a receptor protein called CCR2, and the MGH-led team devised a strategy targeting that molecule to block the inflammatory process but not the action of the reparative monocytes.Small interfering RNA (siRNA) technology prevents production of specific proteins by binding to associated messenger RNA molecules and preventing their translation. However, the technique requires extreme precision in developing the right siRNA molecule and delivering it to the correct cellular location.To make sure that their siRNA preparation targeted the right monocytes, researchers first confirmed that its use reduced levels of CCR2 in monocytes and increased levels of the fragments produced when siRNA binds to its target. They then showed that monocytes from mice treated with the siRNA preparation were unable to migrate towards CCR2's usual molecular target. Experiments in animal models of several important diseases showed that the siRNA preparation reduced the amount of cardiac muscle damaged by a heart attack, reduced the size and the number of inflammatory cells in atherosclerotic plaques and in lymphomas, and improved the survival of transplanted pancreatic islets."These inflammatory monocytes are involved in almost every major disease," Nahrendorf explains. "Anti-inflammatory drugs currently on the market hit every inflammatory cell in the body, which can produce unwanted side effects. This new siRNA treatment doesn't affect inflammatory cells that don't rely on the CCR2 receptor. That makes a big difference."

SAN FRANCISCO, Nov. 11 (Xinhua) -- Logitech, a provider of personal peripherals for computers and other digital platforms, said its production of Google TV was a "big mistake," giving a major blow to Google's aspiration to change the traditional TV experience, U.S. media reported on Friday.According to technology news site The Verge, at a recent analyst and investor meeting, Logitech chief executive officer Guerrino De Luca said the launch of Logitech Revue (with Google TV set-top box) last year was "a mistake of implementation of a gigantic nature."The project cost the company more than 100 million U.S. dollars in operating profit.He said the company had "brought closure to the Logitech Revue saga" and has "no plans to introduce another box to replace Revue" after the inventory runs out this quarter.The CEO also predicted that Google TV will have a chance sometime in the future, but it would be a "grandchild of Google TV " that would do it. Logitech has no plans to help make that happen.Launched during the holiday shopping season last year, the Logitech Revue with Google TV system was criticized for being pricey and unpolished although it gives consumers a streamlined experience of traditional TV content and online media. In August, Logitech slashed the price from 249 dollars to 99 dollars.Last month, Google introduced a redesigned Google TV after sales of the first version did not meet expectations.In April, Logitech reported that Revue with Google TV set-top box and related gear only brought five million dollars in sales during the first quarter of this year, 72 percent less than the company had expected.However, support from some leading TV manufacturers may still help Google fulfill its TV plan. A Bloomberg report said Friday that Google and LG Electronics, world's second-largest TV manufacturer, may unveil a television using the search giant's software at the upcoming Consumer Electronics Show in Las Vegas.Samsung, world's largest TV manufacturer, said in February that it was in discussions with Google to develop a TV product.

SAN FRANCISCO, Dec. 29 (Xinhua) -- The United States Patent and Trademark Office on Thursday published a patent application from Apple related to face and presence detection for iOS devices, which is expected to be one of the next chapters for mobile security.According to AppleInsider, a news and rumor website focusing on Apple, the patent is entitled "low threshold face recognition" which is a low-computation solution for quickly and accurately recognizing a user on iPhone, iPad, iPod Touch and MacBook.Patently Apple, a blog focusing on Apple's latest intellectual properties, said that iOS devices would acknowledge the presence of the potential user by turning on the display and then trigger a subsequent process for recognizing the potential user's face.Currently, most face recognition systems tend to be robust ones working in various lighting conditions, orientations, scale and etc., which will require computing resources and drain battery life. There are also security-type face recognition systems working under controlled lighting conditions which could be ineffective due to factors like proximity of the user to the camera.Google's latest Android 4.0 operating system, codenamed Ice Cream Sandwich, already features face detection. But it is reported that the feature doesn't always work and can be bypassed by using a photograph of the phone's owner.Apple's solution would reduce the impact of lighting conditions and biometric distortions on an image, said AppleInsider, citing the filing. Apple said it would rely on a "high information portion" of a human face, such as eyes, mouth or the tip of a user 's nose.The "likely presence" of a human face in front of the camera would be captured through an "orange-distance filter" which would also be used to detect the potential user's skin tone and measure the distance of their face from the camera.Meanwhile, iOS devices could also be set to recognize faces of multiple users, presenting each user with a personalized configuration.According to AppleInsider, the patent application was first filed by Apple in June, 2009.Analysts said that the proposed technology could be Apple's next big innovation as it has record of redesign and give its unique appeal to products that have not caught on with the general public.

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