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WASHINGTON, Aug. 17 (Xinhua) -- Latest research shows that the Moon could be younger than previous estimates. The findings were published online Wednesday in the Nature journal.The prevailing theory of the Moon's origin is that it was created by a giant impact between a large planet-like object and the proto-Earth. The energy of this impact was sufficiently high that the Moon formed from melted material that was ejected into space. As the Moon cooled, this magma solidified into different mineral components. Analysis of lunar rock samples thought to have been derived from the original magma has given scientists a new estimate of the Moon's age.According to this theory for lunar formation, a rock type called ferroan anorthosite, or FAN, is the oldest of the Moon's crustal rocks, but scientists have had difficulty dating FAN samples. The research team used newly refined techniques to determine the age of a sample of FAN from the lunar rock that was brought back to Earth by the Apollo 16 mission in 1972.The team analyzed the isotopes of the elements lead and neodymium to place the FAN sample's age at 4.36 billion years. This figure is significantly younger than earlier estimates of the Moon's age that range as old as the age of the solar system at 4. 568 billion years. The new, younger age obtained for the oldest lunar crust is similar to ages obtained for the oldest terrestrial minerals -- zircons from western Australia -- suggesting that the oldest crusts on both Earth and Moon formed at approximately the same time, and that this time dates from shortly after the giant impact.This study is the first in which a single sample of FAN yielded consistent ages from multiple isotope dating techniques. This result strongly suggests that these ages pinpoint the time at which the sample crystallized."The extraordinarily young age of this lunar sample either means that the Moon solidified significantly later than previous estimates, or that we need to change our entire understanding of the Moon's geochemical history," Carnegie Institute of Science's geochemist and study author Richard Carlson said.

WASHINGTON, Sept. 12 (Xinhua) -- An enzyme that appears to play a role in controlling the brain's response to nicotine and alcohol in mice might be a promising target for a drug that simultaneously would treat nicotine addiction and alcohol abuse in people, U.S. researchers find.Over the course of four weeks, mice genetically engineered to lack the gene for protein kinase C (PKC) epsilon consumed less of a nicotine-containing water solution than normal mice, and were less likely to return to a chamber in which they had been given nicotine. In contrast, normal mice steadily increased their consumption of nicotine solution while the mice lacking PKC epsilon did not.The study conducted by researchers at the Ernest Gallo Clinic and Research Center, affiliated with the University of California, San Francisco, appeared Monday in the online edition of the Proceedings of the National Academy of Sciences.In normal mice, as in humans, nicotine binds to a certain class of nicotinic receptors located on dopamine neurons, which causes dopamine to be released in the brain. Dopamine creates a feeling of enjoyment, and thus prompts a sense of reward. Researchers found that mice lacking PKC epsilon are deficient in these nicotinic receptors.The finding complements earlier research in which researchers found that mice genetically engineered to lack the PKC epsilon enzyme drank less alcohol than normal mice and were disinclined to return to a chamber in which they had been given alcohol."This could mean that these mice might not get the same sense of reward from nicotine or alcohol," said Gallo senior associate director and investigator Robert Messing. "The enzyme looks like it regulates the part of the reward system that involves these nicotinic receptors."The reward system is a complex of areas in the brain that affect craving for nicotine, alcohol and other addictive substances.The next step in the research, said Messing, would be to develop compounds that inhibit PKC epsilon. The ultimate goal, he added, would be medications that could be used "to take the edge off of addiction by helping people get over some of their reward craving."

SINGAPORE, July 3 (Xinhua) -- The over 60 nursing homes in Singapore, especially those run by voluntary welfare organizations, are facing a bed crunch, local daily Straits Times reported on Sunday.The newspaper found in a check with 20 homes that more than half of the nursing homes were running at full or almost full capacity. Homes run by voluntary welfare organizations, where there are subsidized beds, have long waiting lists.The average waiting time for a bed in nursing homes run by voluntary welfare organizations rose from 50 days in 2008 to about 60 days early last year, the newspaper said.It is easier to get a bed in a privately run home, though only slightly and if you can afford it. Econ Healthcare Group, which runs eight nursing homes in Singapore, said the occupancy rate is 99 percent and it has waiting lists of up to 20 people at some branches.Demand for nursing homes in the city state can only grow given the aging population. By 2030, the number of people aged 65 or above is projected to reach 900,000, or one in every five residents.

WUHAN, Aug. 6 (Xinhua) -- A Chinese man nearing 80 years old was recently diagnosed with HIV and doctors say he probably caught the virus through having "frequent unprotected sex."The case is the latest to support the opinions of experts who believe the virus is spreading fast among older Chinese men who have been largely neglected in the country's anti-AIDS campaigns.The latest diagnosed man, whose identity has been concealed for privacy reasons, was admitted to Zhongnan Hospital in central Chinese city of Wuhan with a lingering fever. He was later found to be HIV positive, doctors at the hospital said Friday.The man was widowed in his old age, has no record of blood transfusions, but had an "active unprotected sexual life," they said.Gao Shicheng, a HIV specialist in Zhongnan Hospital, said that HIV/AIDS has started to infect middle-aged and elderly Chinese men who have little or no AIDS prevention knowledge.Gao said this year alone he had diagnosed two senior men with HIV. Both contracted the virus through unprotected sex outside marriage.A recent survey conducted by the Chinese Center for Disease Control and Prevention (China CDC) shows that among the new HIV infections, the percentage of people aged 50 or above with it grew from 7.8 to 14.9 percent. Most of them were male and were found to have contracted the virus through sexual intercourse.Experts say the spread of HIV/AIDS has picked up among older Chinese men in recent years because China's senior citizens have become healthier, more open-minded about sex, and increasingly bored after retirement.They called for anti-AIDS campaigns, which usually target young people with a focus on gays, sex workers, and rural migrants, to also cover seniors in a bid to raise the awareness of HIV/AIDS prevention knowledge.China is fighting a hard battle to contain the spread of HIV/AIDS. According to a UNAIDS estimate, the country had about 740,000 people living with HIV by the end of 2009. Among them, 105,000 were estimated to have AIDS.By the end of August 2010, the cumulative total of reported HIV positives in China was 361,599, with 65,104 recorded deaths.Sex, other than blood transmission or mother-to-child transmission, has become the main channel for the spread of HIV in China.

BEIJING, Sept. 26 (Xinhuanet) -- One of the world's brightest minds aims to bring to the world a new, advanced three-dimensional image technology that will leave other such technology in the shadows."Our new technology will be better than that used in Avatar," says Professor Yau Shing-tung of Harvard University."The image will be more vivid than with technologies used in previous movies. The new technology is not only quicker but cheaper."Yau is one of the world's greatest mathematicians, having won the prestigious Fields Medal. He was once the dean of the department of mathematics at Harvard, and is now a professor there. He is also a visiting professor at Tsinghua University.Professor Yau and his team met professionals from Tsinghua University and Renmin University of China last week, and they discussed possible cooperation to apply the technology in making a demonstration movie using the new technology.Yau and a team started working on the new 3D technology, founded on geometrical principles, at Harvard 10 years ago.What marks it out is the extremely vivid pictures it produces.3D technology is used not only in making movies and in Internet games but in other areas , such as medicine. Movie audiences the world over were awestruck by the technology used in the movie Avatar."After I watched the movie, all I could say was 'Wow'," said Shen Yiren, an IT staff worker in Zhongguancun Science and Technology Park Zone. "3D technology has extended the boundaries of the human imagination."Yau says that six years ago the makers of Avatar had wanted him to cooperate with them but he turned them down."I was not sure that (Avatar) would be such a big success."Avatar's facial caption technology puts points on models' faces while the new technology uses geometric methods, saving time and money, Yau says.

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