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LOS ANGELES, June 10 (Xinhua) -- The Aquarius/SAC-D observatory, NASA's first ever satellite to study the saltiness of Earth's oceans, is in excellent health after its launch early Friday, initial telemetry reports showed.The observatory rocketed into space from Vandenberg Air Force Base in California atop a United Launch Alliance Delta II rocket at 7:20:13 a.m. PDT (10:20:13 a.m. EDT).Less than 57 minutes later, the observatory separated from the rocket's second stage and began activation procedures, establishing communications with ground controllers and unfurling its solar arrays, NASA's Jet Propulsion Laboratory (JPL) said.During the next 25 days, the Aquarius/SAC-D service platform will be tested and maneuvered into its final operational, near-polar orbit 408 miles (657 kilometers) above Earth. Science operations will begin after the observatory's instruments are checked out. This commissioning phase may last up to 65 days, JPL said.Aquarius will map the global open ocean once every seven days for at least three years with a resolution of 93 miles (150 kilometers). The maps will show how ocean surface salinity changes each month, season and year. Scientists expect to release preliminary salinity maps later this year."Aquarius is a critical component of our Earth sciences work, and part of the next generation of space-based instruments that will take our knowledge of our home planet to new heights," said NASA Deputy Administrator Lori Garver. "The innovative scientists and engineers who contributed to this mission are part of the talented team that will help America win the future and make a positive impact across the globe."Aquarius will measure salinity by sensing thermal microwave emissions from the water's surface with three microwave instruments called radiometers. When other environmental factors are equal, these emissions indicate the saltiness of surface water. A microwave radar scatterometer instrument will measure ocean waves that affect the precision of the salinity measurement.Because salinity levels in the open ocean vary by only about five parts per thousand, Aquarius will be able to detect changes as small as approximately two parts per 10,000, equivalent to about one-eighth of a teaspoon of salt in a gallon of water."Data from this mission will advance our understanding of the ocean and prediction of the global water cycle," said Michael Freilich, director of NASA's Earth Science Division in the Science Mission Directorate at agency headquarters in Washington. "This mission demonstrates the power of international collaboration and accurate spaceborne measurements for science and societal benefit. This would not be possible without the sustained cooperation of NASA, CONAE and our other partners."The Aquarius/SAC-D (Satellite de Aplicaciones Cientificas) observatory is a collaboration between NASA and Argentina's space agency, Comision Nacional de Actividades Espaciales (CONAE).Aquarius was built by NASA's JPL and the Goddard Space Flight Center in Greenbelt, Maryland. NASA's Launch Services Program at the Kennedy Space Center in Florida manages the launch.JPL will manage Aquarius through its commissioning phase and archive mission data. Goddard will manage Aquarius mission operations and process science data. CONAE is providing the SAC-D spacecraft, optical camera, thermal camera with Canada, microwave radiometer, sensors from various Argentine institutions and the mission operations center. France and Italy also are contributing instruments.

BEIJING, Sept. 6 (Xinhuanet) -- Scientists from Tufts University of the U.S. have created the world's smallest electrical motor in a single molecule.The finding was published in the journal Nature Nanotechnology on Monday.In the research, scientist successfully made a single molecule accept an electrical charge and rotate as fast as 120 revolutions per second."This is the first time that electrically-driven molecular motors have been demonstrated, despite a few theoretical proposals," said Charles H. Sykes, professor of chemistry at Tufts who led the team.The single molecule electric motor could lead to new types of electrical circuitry, giving hope for scientists to apply it in medicine and engineering, he said."The next thing to do is to couple it to other molecules, lining them up next to one another so they're like miniature cog-wheels, and then watch the rotation propagation down the chain," said Sykes.

GENEVA, Aug. 19 (Xinhua) -- The World Health Organization (WHO) and the UN Children's Fund (UNICEF) started an emergency vaccination campaign in all accessible areas of South and Central Somalia, WTO spokesperson Tarek Jasarevic said here on Friday.In July 2011 alone, 1,019 suspected measles cases and 31 related deaths were reported in South and Central Somalia, representing 20 percent of all reported cases for this year.The major factors for a measles outbreak in Somalia are low coverage, malnutrition, population movements, and overcrowed internally displaced (IDP) camps."WHO fears that the measles outbreak could affect a high number of people, especially among the vulnerable IDPs whose overall health is already fragile," Jasarevic said.About 2.5 million children aged between 6 and 15 in 10 regions of South and Central Somalia, including children in Mogadishu, will be targeted during this campaign.

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.

ROME, Sept. 27 (Xinhua) -- The 30th general assembly of the International Council for Science (ICSU) kicked off here on Tuesday to address key global challenges, featuring over 275 scientists and experts from all over the world.The goal of the four-day event, hosted for the first time in Rome by the National Research Center (CNR) as Italy's scientific member at ICSU, is to discuss how science can contribute to boosting sustainable development, fighting climate change, increasing well-being and health in the changing urban environment and tackling the side-effects of progress.At the official opening ceremony, CNR president Francesco Profumo stressed that scientific research was the key to solving all current crises."It's during times of crises that inventions, great strategies and discoveries are made," he said quoting Albert Einstein."Global cooperation is crucial in addressing society's needs. In the wake of the negative economic outlook we are witnessing research and technological transfer can turn into efficient instruments to guide countries towards a solid development giving us the tools to tackle with lucidity the great obstacles we face," observed Profumo.Appealing to both private and public institutions, Profumo thus urged to boost strategic partnerships between universities, governments and research centres."We must create a network of knowledge-sharing together with enterprises in order to multiply and better implement growth and well-being opportunities. But in order to do so concrete political decisions must be undertaken and financial resources are needed," he added.

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