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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, Dec. 28 (Xinhuanet) -- China started to run its own satellite positioning system, Beidou, on Tuesday as the country climbed the global tech ladder and challenged the monopoly of the West. Beidou, or Big Dipper, the domestic version of the US Global Positioning System (GPS), started providing navigation, positioning and timing data on a pilot basis to China and the neighboring area for free on Tuesday, Ran Chengqi, director of the China Satellite Navigation Office, said. The system, with 10 orbiting satellites, covers an area from Australia in the south to Russia in the north. Signals can reach the Xinjiang Uygur autonomous region in the west and the Pacific Ocean in the east, Ran said. With six more satellites to be launched next year, the system will cover a wider area and eventually the entire globe by 2020 with a constellation of 35 satellites, he said. The accuracy of the positioning service will also improve as more satellites orbit. During the trial run Beidou can offer positioning to within 25 meters but when the system is officially launched next year accuracy will be enhanced to within 10 meters, he said. With the system operational China is the third member of an elite group, along with the US and Russia, to develop a satellite navigation system. The US spent 20 years and more than billion on the GPS. Completed in 1994, the system has 24 navigation satellites and is widely used around the world. Beidou has its own unique features, Ran said. "It not only tells users where they are and what time it is but also allows users to tell others the information through short messages," Ran said, adding that this feature is being considered by other systems. Russia's Glonass system achieved a 24-satellite constellation in 1996 but succumbed to funding problems. The rebuilding of the Glonass system is almost finished and Russian media reported that the system resumed service earlier this month. The European Union and the European Space Agency are building the Galileo satellite navigation system. Japan and India also intend to build independent regional navigation systems. "Countries build their own systems because owning an independent satellite navigation system is important to economic development and national security," said Pang Zhihao, deputy editor-in-chief of the monthly publication Space International. There have long been concerns that the US might take its dominant GPS offline in certain international emergencies. Ran said that the Beidou system will be "helpful" to national defense. An "independent and controllable" satellite navigation system can guarantee national economic development as well as scientific and industrial strength, he said. China started to reduce its reliance on the GPS in 2000, when it sent an experimental pair of positioning satellites into orbit. But Ran stressed that Beidou is "built for the world", as the compatibility of various systems enhances reliability for users. "If you only use GPS there will be blind spots. But from demonstrations I saw recently, receivers that are compatible with Beidou will overcome these problems," he said. He encouraged enterprises at home and abroad to join the research and development of application terminals compatible with Beidou. The office put a test version of the system's Interface Control Document online on Tuesday, which is a technical document vital for the manufacturing and development of receivers and chips. The prospects for the country's satellite navigation industry look bright, experts said. Analysts estimated that around 2020 the industry's output will reach 0 billion globally, including 400 billion yuan ( billion) to 500 billion yuan from China. According to the 2011 Report on Application of Geosaptial Information in China released on Monday, the number of satellite navigation application terminals in China has grown from less than 100,000 in 2000 to more than 10 million in 2009. The number is expected to reach 340 million by 2015. An insider said a compatible receiver for car use costs 1,600 yuan to 3,000 yuan, higher than a GPS receiver. "Chips supporting both GPS and Beidou systems have been developed, and terminals have been produced. There are no technical hurdles for the industry," said Han Shaowei, CEO of Beijing-based Unicore Communications Inc, a major navigation chip and core component provider. Beidou application terminals have been put into use in vehicles, such as government cars in Guangdong province. Ran said that private terminal makers in Guangdong are testing their receivers on the road, and the products seem stable. "The price of the compatible terminals is expected to be slashed next year," he said.

ISLAMABAD, Oct. 24 (Xinhua) -- Samina, 38, was shocked when doctor told her that she has been suffering from breast cancer for three years and due to late diagnosis the disease spread into her bones making the chances of survival very slim.Samina said that she is trying hard to fight the disease, at the same time she holds the doctors of her village responsible for failing to diagnose the disease in three long years. She is also concerned about her three kids too young to accept any bitter reality."I can't see the distressed faces of my children, I can't bear the fear that looms in their eyes, they know that with every coming day their mother is moving a step forward to death," Samina told Xinhua in a very low tone.When Samina and all other patients of that gloomy medical ward for breast cancer patients, in Nuclear Medicine Oncology and Radiography (NORI) hospital in Islamabad, were told that October is being observed as breast cancer awareness month they murmured that the awareness message should be reached to every nook and corner of the country this year so that no other woman would die due to unawareness.In a country like Pakistan where one in nine women is prone to breast cancer and around 40,000 women die every year due to lack of awareness of this disease. They come to visit oncology department of hospitals at a stage when the chances of survival are very remote.Omer Aftab, National Coordinator of the Pink Ribbon, said that Pakistan has the highest rate of breast cancer among Asian nations. It is the most common malignancy in women, and accounts for 38.5 percent of all female cancer patients, with 90,000 new cases every year.

BEIJING, Oct. 24 (Xinhuanet) -- The average global land temperature has increased by around one degree Cetigrade since the mid-1950s, American scientists announced last week after reviewing historical temperature records to date.According to media reports, the scientists of the Berkeley Earth project have studied more than a billion temperature records dating back to the 1800s from 15 sources around the world.And the result is in line with the estimate made by major institutions which keep official records on the global climate, including the Nasa's Goddard Institute for Space Studies in the US and the Met Office's Hadley Centre in Britain.Meanwhile, the scientists established an open database for the climate records so that skeptics on climate change can assess climage change on their own.Nevertheless, the finding of the scientists at the University of California, Berkeley did not convince climate change skeptics, according to a New York Times report.Anthony Watts, one prominent US skeptics, claimed the study's "methodology was flawed". He also noted that the finding was submitted to journal Geophysical Research Letters before being peer-reviewed.Richard Muller, a physicist and head of the project, argued that the decision to circulate the papers before publication was part a long-standing academic tradition of sanity-checking results with colleagues.He added, cited by the Guardian, "We will get much more feedback from making these papers public before publication."

VIENNA, Dec. 10 (Xinhua) -- China is one of the active supporters of the international community to European crisis settlement, Chinese Vice Foreign Minister Fu Ying said here on Saturday.Attending the fourth World Policy Conference, she voiced the hope that Europe could expand the mutually beneficial cooperation between Europe and China, and create a favorite condition for attracting investment from developing countries including China.In the afternoon, Fu attended a seminar with the topic of "Europe as a laboratory for global governance" and answered questions from the attendants.Asked if China and other BRICS countries should "rescue" Europe or not, she said that the word "rescue" often used by the European media could be misleading.She said that as the world's largest economy, the European Union (EU) has strong real economy and much higher living standard than developing countries. Europe does not need a "savior" but international partners with a win-win relationship.Currently, Europe is facing severe challenges such as the debt crisis and is actively seeking solutions. The EU is China's largest trading partner and one of the main sources of technology and investments. The settlement of crisis in Europe is closely related with not only the world but also China.China has been expressing its confidence in the European economy and the euro, believing that Europe is able to find out solutions to the problems, she said.She also pointed out that the current financial cooperation between Europe and China was mentioned in the same breath with the European financial expansion in Asia in the early 20th century by some European media, which was really a tale of a tub.China sticks to the foreign policy of promoting peace, development and cooperation, and has no intention to control European countries through financial tools, she said.Regarding to the role China played in the settlement of the current European debt crisis, Fu pointed out that China has been an active part of the international community supporting Europe to overcome its crisis.In addition to the cooperation in the financial sector, China also expands its imports, exploring ways to strengthen the investments in Europe and helping create jobs and restore economic growth, according to her.In her speech, she also said that in the process of industrialization, technological innovation, as well as in the fields such as green economy, Europe has always been a leading player in the world.After World War II, European countries learned from their mistakes and started the integration process to create lasting peace. The EU has been successful in maintaining regional peace and promoting economic prosperity. The governance experience in Europe is useful to other regions of the world.However, the European experience should not be completely copied by other regions due to their unique history and real situations.

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