濮阳东方医院治早泄口碑非常高(濮阳市东方医院咨询预约) (今日更新中)

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, Aug. 2 (Xinhua) -- A new study has identified the recent emergence of a multidrug-resistant strain of Salmonella that has a high level resistance to ciprofloxacin, a common treatment for severe Salmonella infections. The study was published on-line Tuesday in The Journal of Infectious Diseases.Francois-Xavier Weill at the Pasteur Institute in France and colleagues studied information from national surveillance systems in France, England and Wales, Denmark, and the United States. The data showed that a multidrug-resistant strain of Salmonella, known as S. Kentucky, infected 489 patients in France, England and Wales, and Denmark between 2000 and 2008. In addition, researchers reported that the first infections were acquired mainly in Egypt between 2002 and 2005, while since 2006 the infections have also been acquired in various parts of Africa and the Middle East. The absence of reported international travel in approximately 10 percent of the patients suggests that infections may have also occurred in Europe through consumption of contaminated imported foods or through secondary contaminations.In this study, multidrug-resistant S. Kentucky was isolated from chickens and turkeys from Ethiopia, Morocco, and Nigeria, suggesting that poultry is an important agent for infection. The common use of fluoroquinolones in chicken and turkey production in Nigeria and Morocco may have contributed to this rapid spread, according to the researchers.This study highlights the importance of public health surveillance in a global food system. The investigators reported that they will continue to monitor this multidrug-resistant strain as well as help strengthen the capacities of national and regional laboratories in the surveillance of Salmonella and other major foodborne pathogens through the World Health Organization Global Foodborne Infections Network.Salmonella infection represents a major public health problem worldwide. An estimated 1.7 million such infections occur in North America each year. More than 1.6 million cases were reported between 1999 and 2008 in 27 European countries. Although most Salmonella infections produce only mild gastroenteritis, elderly and immunocompromised patients are especially at risk for life- threatening infections. These cases are typically treated with antimicrobials called fluoroquinolones, such as ciprofloxacin.

NANNING, Sept. 1 (Xinhua) -- In south China's Guangxi Zhuang Autonomous Region, an area renowned for its history of musical folklore, local residents have found a unique way to spread knowledge regarding AIDS prevention."All people unite to fight AIDS! AIDS will stay away if we are equipped with AIDS knowledge," state the lyrics of one song that was penned by local songwriters as part of a local anti-AIDS campaign."We asked eight local singers to write and record songs about the disease. We think this is an effective way for local people to acquire AIDS knowledge," said 55-year-old Huang Zhanghui, a resident of the village of Shantun. He said that the songs are played through loudspeakers in his village every evening.The songwriting campaign has been effective because folk songs are a traditional artform in the region, making them more readily understandable and acceptable for local residents, Huang said.Guangxi has been one of the hardest-hit areas in China in terms of the number of AIDS infections discovered there, ranking only after central China's Henan Province. More than 76 percent of the infections are sexually transmitted, according to Ge Xianmin, an official from the AIDS prevention office of the Guangxi regional government.Bama County, which administers Shantun, is known for the longevity of its residents. Nearly 2,500 of its residents are more than 80 years old, and another 81 have celebrated their 100th birthdays."We will not let AIDS threaten this tradition," Huang said.Huang was selected to be the head of the village's AIDS prevention office just two months ago. In addition to the creation of folk songs, the office spreads AIDS prevention knowledge through text messages and publicly screened films.

LOS ANGELES, Sept. 10 (Xinhua) -- Scientists at the University of California Los Angeles campus have announced that they have successfully used new prediction algorithms to forecast climate up to 16 months in advance.Professor Michael Ghil said in a UCLA news release Friday his team used new prediction algorithms based on matching ocean temperature records with new theories on how long-term climate trends are influenced by short-term weather extremes.That's twice as far into the future as previously accomplished.Ghil, a distinguished professor of climate dynamics in the UCLA Department of Atmospheric and Oceanic Sciences and senior author of the research, said the new prediction formulas will give climate experts and governments clues about long-term swings in the El Nino/La Nina oscillation in the Pacific Ocean, which drastically affects weather in the Americas, Asia and Australia.The new forecasting tool uses sea temperatures and has been tested on decades of historical data. The forecasts were then cross-checked against actual climate trends.The UCLA team also said that their 16-month forecasts were more accurate than previous forecasts that went only 8 months forward.Ghil emphasized that the forecasting tools are for climate, which is long-range, global patterns, but not for meteorology, which is short-term weather forecasting."Certain climate features might be predictable, although not in such detail as the temperature and whether it will rain in Los Angeles on such a day two years from now," said Ghil, who is also a member of UCLA's Institute of Geophysics and Planetary Physics. "These are averages over larger areas and longer time spans."The study is currently available online in the journal Proceedings of the National Academy of Sciences (PNAS) and will be published in an upcoming print edition of the journal.

CANBERRA, Sept. 9 (Xinhua) -- Australia on Friday launched the first national study to find out whether low to moderate levels of alcohol drank by pregnant women are harmful or not to an unborn child, hoping to provide a clear indication about the safe amount of alcohol for pregnant women.The Murdoch Children's Research Institute in Melbourne, which commissioned the study, is recruiting 2000 pregnant women who will be quizzed throughout their pregnancy about their drinking habits, general health and diets.Their babies will then undergo medical checks, when they turn one and again at two to see if their brains, development and behavior was affected by alcohol consumed by their mums.According to lead researcher associate professor, Jane Halliday, while there was solid evidence about the dangers of heavy drinking for an unborn baby, it was not known if there was a safe amount of alcohol pregnant women could drink.She said the study hoped to shed light on the best approach to alcohol use during pregnancy."The problem is that for about half of women that get pregnant it is unplanned, and a lot of women are drinking around the time they get pregnant and may drink for the first month or so and that creates a lot of anxiety," Assoc Prof Halliday said in a statement."From the few international and Australian studies there's conflicting evidence as to whether there's an adverse effect."We firmly believe that no drinking is the safest option, but our main aim is to provide an evidence base to the policy and answer questions about individual risks."The study came after research by the University of Newcastle published in 2010 revealed 80 percent of Australian women drank during pregnancy.

来源：资阳报