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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, Oct. 18 (Xinhuanet) -- NASA recently unveiled its new rocket design, named Space Launch System (SLS), according to media reports.The rocket will make its first unmanned flight in 2017, and the flight with astronauts aboard won't happen until 2021, according to NASA's plan.The new rocket was 320 feet in length (the space shuttle was 184 feet on the launch pad), 5.5 million pounds in weight, and with the capacity of holding four astronauts at the top speed of 25,000 miles per hour, Washington Post reported Tuesday.Compared with space shuttle and other predecessors, the new rocket will aim for much farther destinations into the space with its most powerful engine ever built, according to the plan."We're investing in technologies to live and work in space, and it sets the stage for visiting asteroids and Mars," the NASA administrator Charles Bolden briefed the media at a news conference in Washington.NASA expected to devote 3 billion U.S. dollars a year to the effort, or a total of about 18 billion U.S. dollars over the next six years, said William Gerstenmaier, the agency’s associate administrator for human exploration.The current financial condition of U.S. may slow down the pace of progress, which will be much slower than NASA's Apollo heyday in the 1960s.

BEIJING, Dec. 7 (Xinhua) -- China backs European efforts for further integration and supports current initiatives by the European Union to tackle the debt crisis, Chinese Foreign Ministry spokesman Hong Lei said Wednesday.Hong told a regular press briefing that China will work with the international community to help stabilize the global financial market and promote the recovery and growth of the world economy."We have noted that the EU has made a series of important proposals to address the European sovereign debt crisis and we hope such proposals can work to help stabilize the market, restore market faith and prevent the crisis from deteriorating," Hong added.Europe's powerhouses France and Germany agreed Monday on a series of reforms aimed at changing the European Union treaty to impose tough controls on eurozone budgets.The new treaty would include automatic sanctions for states that fail to observe the 3 percent deficit rule, as well as a budget-balancing rule across the eurozone.New and significant decisions to tackle the crisis might be made during the EU summit to be held from Dec. 8 to 9, Hong predicted.Leaders from the 27 member states of the European Union will meet in Brussels on Dec. 8-9 to discuss how to resolve the eurozone crisis.

BEIJING, Nov. 13 (Xinhua) -- A campaign that aims to boost the public's role in safeguarding food safety and promote awareness of the issue was launched at the 9th China Food Safety Annual Conference, which closed on Sunday.Food safety has a bearing on people's health as well as the nation's sound and harmonious development, said Shi Xiushi, chairman of the Financial and Economic Committee of China's National People's Congress (NPC), at the opening, calling for efforts to raise companies' sense of responsibility and consumers' awareness in preventing and dealing with food safety crimes.The new campaign is part of a broader five-year program (2011-2015) of food safety education announced by the State Council Food Safety Commission (SCFSC) in May.The program aims for more than 80 percent of the public to be aware of basic food safety by 2015, with the rate for primary and high-school students reaching up to 85 percent or more.ARDUOUS WORKFood safety has become a growing public concern in China following a string of scandals over recent years. In the latest one, illegal workshops were found making and selling "gutter oil," which is processed from leftovers dredged from gutters.Gu Xiulian, former vice chairwoman of the NPC's Standing Committee, the country's top legislature, said ensuring safety is the top priority for the food sector, the country's pillar industry with an output of 550 million yuan (97.3 million U.S. dollars) in the first nine months of 2011.The development of the nation's food safety has failed to keep up with the demands of a public whose living standards have improved substantially in recent years, said Shi.Pledging to do everything it can to ensure food safety, the government takes a zero-tolerance approach to companies that sell unsafe food. In 2010 alone, authorities across the country investigated and handled 130,000 cases of food safety violations, shutting down more than 100,000 companies, according to the SCFSC."The food industry's overall development level is relatively low. There are weak links in the sector's credibility, management, detection techniques and even the laws and regulations," said Pu Changcheng, deputy director of the Administration of Quality Supervision, Inspection and Quarantine.Pu's points are exemplified by China's agricultural industry, which is largely based around small-scale production managed by disparate bodies. It would be a formidable task to eradicate the sector's safety issues.The catering business also faces a similar plight. The country has issued licenses to 2.2 million catering companies, most of which are small and individually operated, making safety supervision extremely difficult, according to Bian Zhenjia, deputy head of the State Food and Drug Administration.

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