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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.

BEIJING, Jan. 1 (Xinhua) -- Chinese President Hu Jintao and his South Korean counterpart Lee Myung-bak exchanged new year greetings Sunday and announced the start of the "China-South Korea Friendly Exchange Year".In his message, Hu spoke positively of the relations between the two countries. Seizing the opportunity of the 20th anniversary of the establishment of the China-South Korea diplomatic relations, China is willing to work together with South Korea, by launching various exchange programs, to further promote mutual understanding and friendship between the two peoples, deepen communication and cooperation in all sectors, and push for constant progress of the bilateral relationship, Hu said.For his part, Lee said on the basis of the accomplishments achieved over the two decades of the bilateral diplomatic ties, South Korea looks forward to joining hands with China to build a better future for the bilateral relationship.

SAN FRANCISCO, Nov. 9 (Xinhua) -- Cisco Systems Inc., the world 's biggest networking equipment maker, on Wednesday reported that its profit fell about 7.9 percent in the most recent quarter.In the company's fiscal 2012 first quarter ending on Oct. 29, Cisco posted its net income of nearly 1.78 billion U.S. dollars, compared with 1.93 billion dollars in the same period a year earlier.Excluding some items, earnings per share in the quarter were 43 cents, better than the 39 cents estimated by analysts, according to Bloomberg.Cisco's sales in the quarter reached 11.26 billion dollars, an increase of 4.7 percent year-on-year and also topped analysts' projection of about 11 billion dollars."We delivered a solid quarter," John Chambers, Cisco's chief executive officer, said in a statement."We've completed the majority of our restructuring and have organized Cisco to successfully execute against our strategy of providing intelligent networks, architectures and integrated products that solve customers' business problems," he added.

BEIJING, Jan. 17 (Xinhuanet) -- India has reported the first case of "totally drug-resistant tuberculosis," a long-feared and virtually untreatable form of the killer lung disease.Similar highly resistant cases have been noted before. In 2003, two Italian women died and there were 15 cases reported from Iran in 2009. That same year, The Associated Press reported on a case of a Peruvian teenager who was infected at home but diagnosed while visiting Florida.Such kind of TB has mostly been limited to impoverished areas, and has not spread widely. But experts believe there could be many undocumented cases.No one expects the Indian TB strains to rapidly spread elsewhere.The airborne disease is mainly transmitted through close personal contact and isn't nearly as contagious as the flu. Indeed, most of the cases of this kind of TB were not from person-to-person infection but were mutations that occurred in poorly treated patients.The Indian hospital that saw the initial cases tested a dozen medicines and none of them worked. A TB expert at the U.S. Centers for Disease Control and Prevention said they do appear to be totally resistant to available drugs."It is concerning," said Dr. Kenneth Castro, director of the CDC's Division of Tuberculosis Elimination. "Anytime we see something like this, we better get on top of it before it becomes a more widespread problem."Ordinary TB is easily cured by taking antibiotics for six to nine months. However, if that treatment is interrupted or the dose is cut down, the stubborn bacteria battle back and mutate into a tougher strain that can no longer be killed by standard drugs. The disease becomes harder and more expensive to treat.Tuberculosis is an age-old scourge that lies dormant in an estimated one in three people. About 10 percent of those people eventually develop active TB, which kills roughly 2 million a year, according to WHO. Each victim infects an average of 10 to 15 others every year, typically through sneezing or coughing.If a TB case is found to be resistant to the two most powerful anti-TB drugs, the patient is classified as having multi-drug-resistant TB (MDR). An even worse classification of TB — one the WHO accepts — is extensively drug-resistant TB (XDR), a form of the disease that was first reported in 2006 and is virtually resistant to all drugs.About 20 percent of the world's multi-drug-resistant cases were found in India, which is home to a quarter of all types of tuberculosis cases worldwide.

BEIJING, Nov. 13 (Xinhua) -- China has established an operation committee for management of the country's first space lab module, Tiangong-1, during its two-year orbit of earth.The committee will deal with operations planning, technical appraisal and flight control of the target orbiter after the unmanned Shenzhou-8 spacecraft returns to earth after its mission, the official website of China's manned space program said.The Tiangong-1 space lab module was launched on Sept. 29 and docked with Shenzhou-8 precisely on Nov. 3, China's first ever space docking attempt. The second docking between Tiangong-1 and Shenzhou-8 is scheduled for Nov. 14.The manned space program said earlier that the same target orbiter Tiangong-1 will accommodate another two docking missions performed by two other Shenzhou spaceships, at least one of which will be manned.The 8.5-tonne Tiangong-1 is the first space lab module that China has built, and the committee will also be the first in taking care of a long-running space asset.The operation committee for Tiangong-1 heralds China's manned space program entering a new phase for lengthy flight missions, Niu Hongguang, director of the operation committee, said on the website www.cmse.gov.cn.The orbiting module management will include taking care of the space lab, making preparations for any further docking tests and gathering experience for building a future space station, Niu said.

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