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WASHINGTON, Dec. 7 (Xinhua) -- Drugs that affect the levels of an important brain protein involved in learning and memory reverse cellular changes in the brain seen during aging, according to an animal study published Wednesday in the Journal of Neuroscience. The findings could one day aid in the development of new drugs that enhance cognitive function in older adults.Aging-related memory loss is associated with the gradual deterioration of the structure and function of synapses (the connections between brain cells) in brain regions critical to learning and memory, such as the hippocampus.Recent studies suggested that histone acetylation, a chemical process that controls whether genes are turned on, affects this process. Specifically, it affects brain cells' ability to alter the strength and structure of their connections for information storage, a process known as synaptic plasticity, which is a cellular signature of memory.In the current study, Cui-Wei Xie, of the University of California, Los Angeles, and colleagues found that compared with younger rats, hippocampi from older rats have less brain-derived neurotrophic factor (BDNF) -- a protein that promotes synaptic plasticity -- and less histone acetylation of the Bdnf gene. By treating the hippocampal tissue from older animals with a drug that increased histone acetylation, they were able to restore BDNF production and synaptic plasticity to levels found in younger animals."These findings shed light on why synapses become less efficient and more vulnerable to impairment during aging," said Xie, who led the study. "Such knowledge could help develop new drugs for cognitive aging and aging-related neurodegenerative diseases, such as Alzheimer's disease," she added.

MOSCOW, Oct. 3 (Xinhua) -- A Soyuz-2.1B rocket carried a Glonass-M navigation satellite into orbit early Monday after a two-day delay caused by high winds, a Russian Space Forces spokesman said."The launch of the booster rocket is as scheduled. The satellite Glonass-M was put into the orbit under control at 03:55 Moscow time (2355 GMT on Sunday)," said Colonel Alexei Zolotukhin.Zolotukhin told reporters that the rocket was launched at 0:15 Moscow time (2015 GMT, Sunday) from the Plesetsk Space Center in northern Russia.The Russian Space Forces said the launch was initially scheduled for Saturday but was postponed due to high winds.Glonass is the Russian equivalent of the U.S. Global Positioning System (GPS), which is designed for both military and civilian use. The system requires 24 operational and 2-3 reserve satellites in orbit to ensure global coverage.In December 2010, a malfunction of the booster resulted in a loss of three Glonass satellites.

BEIJING, Jan. 14 (Xinhua) -- China and member countries of the Association of Southeast Asian Nations (ASEAN) on Saturday held a meeting of senior officials on the implementation of the Declaration on the Conduct of Parties in South China Sea.All the participants had in-depth discussion and reached a series of consensus, said a press release posted on the Foreign Ministry's official website (www.fmprc.gov.cn).The meeting concluded that the general situation of South China Sea is peaceful and stable, and appreciated the positive efforts from all concerned sides.The meeting regarded 2011 as a fruitful year with positive progress made in implementing the declaration, and reached consensus on the future works, including to speed up specific cooperation projects, and to host seminars on maritime disaster-relief, environment, rescue and biology research.All the parties agreed to set up experts committees on maritime scientific research, environmental protection, security and rescue, and on the crackdown on cross-border crimes, and to better utilize the China-ASEAN fund on maritime cooperation.

BEIJING, Oct. 20 (Xinhuanet) -- A Teenager's intelligence is not fixed as usually thought. Instead, it can go through swings in a few years, according to a British study reported online in Nature.Teenagers' IQ can rise or fall 20 points over time, researchers from Wellcome Trust Centre for Neuroimaging of Kings College, showed in their study.IQ (short for "intelligent quotient") is an gauge of mental capability measured through a series of standardized tests of language skill, spatial ability, arithmetic, memory and reasoning.To get the findings, Cathy Price, senior researcher of the study, and her colleagues tested 33 British teenagers between the ages of 12 to 16 in 2004, who had average IQ scores around 100. Then the teenagers were retested four years later.The researchers found the volunteers' IQ scores went up and down over the four years, with some teenager's scores rising by as many as 20 points, and others' dropping by the same points."That is quite astounding," cheered psychologist Robert Plomin from the same university but not involved in the study. Dr. Price and her colleagues don't know the causes of such fluctuations in the scores they tested, but speculate that learning experiences might account the changes, reported by the Wall Street Journal Today. "We have to be careful not to write off poorer performers at an early stage when in fact their IQ may improve significantly given a few more years," stated Dr. Price cited by the Huffington Post.

HONOLULU, United States, Nov. 12 (Xinhua) -- Chinese President Hu Jintao said here Saturday that China will deepen economic structural reform, grow a green economy, enhance protection of intellectual property rights and open wider to the outside world.Hu made the remarks at the CEO summit of the Asia-Pacific Economic Cooperation (APEC) ahead of the APEC Economic Leaders' Meeting.Hu noted that while China's economy has grown steadily and the country is opening wider to the outside world, China still faces the major challenge of unbalanced, uncoordinated and unsustainable development.China, he said, will continue to deepen reform and opening-up, improve people's livelihood and promote sustained, steady and fairly fast economic growth and social harmony and stability.Hu then laid out a four-point proposal to achieve the goals, with the first being that China will deepen economic structural reform and improve business and investment environment.Second, China will honor its commitment to growing a green economy and promoting the conservation culture, Hu said.From 2011 to 2015, China's investment in the environmental sector will double that of the previous five years to about 3.1 trillion yuan (about 488.5 billion U.S. dollars), Hu said, adding that China's green industry is a key area for foreign investment.Third, China will step up protection of intellectual property rights and make itself a country driven by innovation, he said.China will vigorously boost scientific and technological innovation and turn enterprises into major players of such innovation, while further improving the legal system for intellectual property rights protection, he said.Fourth, China will open wider to the outside world and take an active part in global economic governance and regional cooperation, Hu said.China, he said, will give equal importance to import and export and focus more on increasing import while maintaining a stable level of export.Noting that China's development constitutes an important force driving regional and global economic growth, Hu said that China will work together with others to create a better future for the Asia-Pacific region.

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