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WASHINGTON, Jan. 16 (Xinhua) -- A new study examining weather patterns around the worldwide pandemics of influenza, which caused widespread death and illness in 1918, 1957, 1968 and 2009, finds that each of them was preceded by La Nina conditions in the equatorial Pacific. The study findings are published online Monday in the Proceedings of the National Academy of Science.The study's authors -- Jeffrey Shaman of Columbia University's Mailman School of Public Health and Marc Lipsitch of the Harvard School of Public Health -- note that the La Nina pattern is known to alter the migratory patterns of birds, which are thought to be a primary reservoir of human influenza. The scientists theorize that altered migration patterns promote the development of dangerous new strains of influenza.To examine the relationship between weather patterns and influenza pandemics, the researchers studied records of ocean temperatures in the equatorial Pacific in the fall and winter before the four most recent flu pandemics emerged. They found that all four pandemics were preceded by below-normal sea surface temperatures -- consistent with the La Nina phase of the El Nino- Southern Oscillation.The authors cite other research showing that the La Nina pattern alters the migration, stopover time, fitness and interspecies mixing of migratory birds. These conditions could favor the kind of gene swapping or genetic reassortment that creates novel and therefore potentially more variations of the influenza virus."We know that pandemics arise from dramatic changes in the influenza genome. Our hypothesis is that La Nina sets the stage for these changes by reshuffling the mixing patterns of migratory birds, which are a major reservoir for influenza," says Shaman.Changes in migration not only alter the pattern of contact among bird species, they could also change the ways that birds come into contact with domestic animals like pigs. Gene-swapping between avian and pig influenza viruses was a factor in the 2009 swine flu pandemic.
BEIJING, Jan. 1 (Xinhua) -- President Hu Jintao, along with other Chinese leaders, celebrated the New Year with political advisors Sunday morning in Beijing and delivered an important speech.Hu and the other members of the Standing Committee of the Political Bureau of the Communist Party of China (CPC) Central Committee Wu Bangguo, Wen Jiabao, Jia Qinglin, Li Changchun, Xi Jinping, Li Keqiang, He Guoqiang and Zhou Yongkang attended a tea party held by the National Committee of the Chinese People's Political Consultative Conference (CPPCC).

UNITED NATIONS, Oct. 28 (Xinhua) -- China's progress in meeting a development goal on children's health can serve as an inspiration to other countries working towards the same objective, Dr. Renee Van de Weerdt, chief of maternal, newborn and child health at the UN Children's Fund (UNICEF) told Xinhua in an interview Friday.Van de Weerdt said that "the example of China is very encouraging because it means it can be done, even in a very big country with a very big population."China is on track to meet the fourth Millennium Development Goal (MDG), one of the eight development targets that the international community has pledged to meet by 2015. MDG 4 requires that each country reduce its rate of mortality for children under age five to two-thirds of what it was in 1990.According to Van de Weerdt, most deaths of children under five take place in the first month of life. After the first month, the most prevalent causes of death are pneumonia and diarrhea.ACHIEVING THE GOAL WORLDWIDEThe international community has been doing "relatively well" in working towards achieving MDG 4, Van de Weerdt said.The UN Interagency Group for Child Mortality Estimation (IGME) stated in their 2011 Report on Levels and Trends in Child Mortality that the number of under-five deaths worldwide has dropped from more than 12 million in 1990 to 7.6 million in 2010."We really continue to see progress," Van de Weerdt said. "The number of children that die every year continues to drop so we are really pleased to see that progress. Unfortunately, the progress isn't sufficient to really be able to say that if we continue at this pace we would achieve MDG 4 by 2015."Some regions, according to Van de Weerdt, like Latin America and parts of Asia are making more headway towards the goal than others that are currently lagging behind.
BEIJING, Dec. 7 (Xinhua) -- The Chinese government on Wednesday released a white paper on its foreign trade, highlighting the country's achievements in boosting foreign trade and contribution to the world economy.The white paper, titled China's Foreign Trade, was released by the Information Office of the State Council.The white paper introduces China's historic progress, international contribution and policies in foreign trade.
WASHINGTON, Nov. 10 (Xinhua) -- Using its near-infrared vision to peer nine billion years back in time, NASA's Hubble Space Telescope has uncovered an extraordinary population of young dwarf galaxies brimming with star formation, the U.S. space agency announced on Thursday.While dwarf galaxies represent the most common type of galaxy in the universe, the rapid star-birth observed in these newly- found examples may force astronomers to reassess their understanding of the ways in which galaxies form.The galaxies are a hundred times less massive, on average, than the Milky Way, yet they churn out stars at such a furious pace that their stellar content would double in just 10 million years. By comparison, the Milky Way would take a thousand times longer to double its star population.The universe is estimated to be 13.7 billion years old, and these newly-discovered galaxies are extreme even for the young universe -- when most galaxies were forming stars at higher rates than they are today. Astronomers using Hubble's instruments could spot the galaxies because the radiation from young, hot stars has caused the oxygen in the gas surrounding them to light up like a bright neon sign."The galaxies have been there all along, but up until recently astronomers have been able only to survey tiny patches of sky at the sensitivities necessary to detect them," said Arjen van der Wel of the Max Planck Institute for Astronomy in Germany, lead author of a paper on the results to be published online on Nov. 14 in The Astrophysical Journal. "We weren't looking specifically for these galaxies, but they stood out because of their unusual colors. "The observations were part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), an ambitious three- year study to analyze the most distant galaxies in the universe. CANDELS is the first census of dwarf galaxies at such an early epoch."In addition to the images, Hubble has captured spectra that show us the oxygen in a handful of galaxies and confirmed their extreme star-forming nature," said co-author Amber Straughn at NASA's Goddard Space Flight Center. "Spectra are like fingerprints. They tell us the galaxies' chemical composition."The CANDELS team uncovered the 69 young dwarf galaxies in near- infrared images taken with Hubble's Wide Field Camera 3 and Advanced Camera for Surveys.The observations suggest that the newly-discovered galaxies were very common nine billion years ago. However, it is a mystery why the newly-found dwarf galaxies were making batches of stars at such a high rate.
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