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LOS ANGELES, June 23 (Xinhua) -- The sun and its inner planets may have formed differently than previously thought, NASA's Jet Propulsion Laboratory (JPL) said on Thursday.Data revealed differences between the sun and planets in oxygen and nitrogen, which are two of the most abundant elements in our solar system, said JPL in Pasadena, Los Angeles.Although the difference is slight, the implications could help determine how our solar system evolved, JPL said.NASA researchers drew the conclusion after analyzing samples returned by NASA's 2004 Genesis mission, according to JPL.The air on Earth contains three different kinds of oxygen atoms which are differentiated by the number of neutrons they contain. Nearly 100 percent of oxygen atoms in the solar system are composed of O-16, but there are also tiny amounts of more exotic oxygen isotopes called O-17 and O-18. Researchers studying the oxygen of Genesis samples found that the percentage of O-16 in the sun is slightly higher than on Earth or on other terrestrial planets. The other isotopes' percentages were slightly lower."We found that Earth, the moon, as well as Martian and other meteorites which are samples of asteroids, have a lower concentration of the O-16 than does the sun," said Kevin McKeegan, a Genesis co-investigator from University of California, Los Angeles (UCLA) and the lead author of one of two papers published this week in Science journal. "The implication is that we did not form out of the same solar nebula materials that created the sun -- just how and why remains to be discovered." Another paper detailed differences between the sun and planets in the element nitrogen. Like oxygen, nitrogen has one isotope, N- 14, that makes up nearly 100 percent of the atoms in the solar system, but there is also a tiny amount of N-15. Researchers studying the same samples saw that when compared to Earth's atmosphere, nitrogen in the sun and Jupiter has slightly more N-14, but 40 percent less N-15. Both the sun and Jupiter appear to have the same nitrogen composition. As is the case for oxygen, Earth and the rest of the inner solar system are very different in nitrogen."These findings show that all solar system objects including the terrestrial planets, meteorites and comets are anomalous compared to the initial composition of the nebula from which the solar system formed," said Bernard Marty, a Genesis co- investigator from Petrographic and Geochemical Research Center in Fracne and the lead author of the other new Science paper. " Understanding the cause of such a heterogeneity will impact our view on the formation of the solar system."Data were obtained from analysis of samples Genesis collected from the solar wind, or material ejected from the outer portion of the sun. This material can be thought of as a fossil of our nebula because the preponderance of scientific evidence suggests that the outer layer of our sun has not changed measurably for billions of years."The sun houses more than 99 percent of the material currently in our solar system, so it's a good idea to get to know it better, " said Genesis Principal Investigator Don Burnett of the California Institute of Technology, Pasadena, California. "While it was more challenging than expected, we have answered some important questions, and like all successful missions, generated plenty more."Genesis was launched in August 2000. The spacecraft traveled to Earth's L1 Lagrange Point about one million miles from Earth, where it remained for 886 days between 2001 and 2004, passively collecting solar-wind samples.JPL managed the Genesis mission for NASA's Science Mission Directorate, Washington. The Genesis mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Alasca.

XICHANG, Sichuan, July 27 (Xinhua)-- China successfully launched an orbiter into space at 5:44 a.m. Beijing Time Wednesday, as a part of its indigenous satellite navigation and positioning network known as Beidou, or Compass system, sources with the launch center said.The orbiter,launched from the Xichang Satellite Launch Center in southwestern Sichuan Province, was boosted by a Long March-3A carrier rocket into a geostationary orbit.China started to build up its own satellite navigation system to break its dependence on the U.S. Global Positioning System (GPS) in 2000.A Long March-3A carrier rocket lifts off at the Xichang Satellite Launch Center in southwest China's Sichuan Province, July 27, 2011. China successfully launched into space a ninth orbiter for its independent satellite navigation and positioning network known as Beidou, or Compass System here early WednesdayBetween October 2000 and May 2003, the country set up a regional satellite navigation system after launching three Beidou geostationary satellites.The system was known as Beidou-1 and is said to have played an important role in the rescue efforts following the devastating earthquake in May 2008 in Wenchuan as it provided the only channel connecting the quake-hit area and the outside.The Beidou-1 system can not meet growing demand, so a better functional Beidou-2 regional and global navigation system will be set up, Qi Faren, former chief designer for Shenzhou spaceships said in an interview with Xinhua early this year.From April 2007 to April this year, China launched another eight orbiters to form its Beidou-2 system, which will eventually consist of 35 satellites.The network will provide satellite navigation, time and short message services for Asia-Pacific regions by 2012 and global services by 2020.

BEIJING, Aug. 2 (Xinhuanet) -- The first close-up pictures of the asteroid Vesta, a protoplanet that dates back to the early days of the solar system, were revealed Monday by NASA scientists.The images were taken by the U.S. space agency's Dawn robotic probe, which is two weeks into a planned year-long survey of the second largest object in the main asteroid belt, located between Mars and Jupiter.About twice the size of California, Vesta is second in size only to Ceres, Dawn's next target and, along with Pluto, one of just five known dwarf planets. NASA is spending 466 million dollars to explore Vesta and Ceres during the course of a 10-year mission.Images from Dawn show Vesta a surprisingly diverse terrain and several unexplained geologic features. Chaotic terrain near the south pole is dominated by a towering central peak and huge ripple-like grooves stretching around its equatorial belt. Bright spots, dark pits and craters are filled with unexplained streaks of black and white debris. Terrain north of the grooves is much more heavily cratered.Scientists believe Vesta grew from a clump of gas and dust left over after the sun's birth some 4.65 billion years ago, a supernova explosion, which added radioactive materials to the growing body.Dawn will spend about a year circling Vesta, tweaking its orbit and altitude using an innovative technology called ion propulsion system, chief engineer Marc Rayman with NASA's Jet Propulsion Laboratory in California said.The ion propulsion system will enable Dawn to leave Vesta's orbit after a year of study and head off to Ceres, which is the largest object in the asteroid belt.

WASHINGTON, July 15 (Xinhua) -- Researchers at Mount Sinai School of Medicine have found that grape seed polyphenols -- a natural antioxidant -- may help prevent the development or delay the progression of Alzheimer's disease.The research, led by Giulio Pasinetti, was published online Friday in the Journal of Alzheimer's Disease, which causes brain changes that gradually get worse.This is the first study to evaluate the ability of grape- derived polyphenols to prevent the generation of a specific form of amyloid (A) peptide, a substance in the brain long known to cause the neurotoxicity associated with Alzheimer's disease.In partnership with a team at the University of Minnesota, Pasinetti and collaborators administered grape seed polyphenolic extracts to mice genetically determined to develop memory deficits and A neurotoxins similar to those found in Alzheimer's disease. They found that the brain content of the A*56, a specific form of A previously implicated in the promotion of Alzheimer's disease memory loss, was substantially reduced after treatment.Previous studies suggest that increased consumption of grape- derived polyphenols, whose content, for example, is very high in red wine, may protect against cognitive decline in Alzheimer's. This new finding corroborates those theories."Since naturally occurring polyphenols are also generally commercially available as nutritional supplements and have negligible adverse events even after prolonged periods of treatment, this new finding holds significant promise as a preventive method or treatment, and is being tested in translational studies in Alzheimer's disease patients," said Pasinetti.In Alzheimer's disease, brain cells degenerate and die, causing a steady decline in memory and mental function.

WASHINGTON, June 14 (Xinhua) -- Eating a low-carbohydrate, high- protein diet may reduce the risk of cancer and slow the growth of tumors already present, according to a study published Tuesday in Cancer Research, a journal of the American Association for Cancer Research.The study was conducted in mice, but the scientists involved agree that the strong biological findings are definitive enough that an effect in humans can be considered."This shows that something as simple as a change in diet can have an impact on cancer risk," said lead researcher Gerald Krystal, a scientist at the British Columbia Cancer Research Center.Krystal and his colleagues implanted various strains of mice with human tumor cells or with mouse tumor cells and assigned them to one of two diets. The first diet, a typical Western diet, contained about 55 percent carbohydrate, 23 percent protein and 22 percent fat. The second, which is somewhat like a South Beach diet but higher in protein, contained 15 percent carbohydrate, 58 percent protein and 26 percent fat. They found that the tumor cells grew consistently slower on the second diet.As well, mice genetically predisposed to breast cancer were put on these two diets and almost half of them on the Western diet developed breast cancer within their first year of life while none on the low-carbohydrate, high-protein diet did. Interestingly, only one on the Western diet reached a normal life span ( approximately 2 years), with 70 percent of them dying from cancer while only 30 percent of those on the low-carbohydrate diet developed cancer and more than half these mice reached or exceeded their normal life span.Krystal and colleagues also tested the effect of an mTOR inhibitor, which inhibits cell growth, and a COX-2 inhibitor, which reduces inflammation, on tumor development, and found these agents had an additive effect in the mice fed the low-carbohydrate, high-protein diet.When asked to speculate on the biological mechanism, Krystal said that tumor cells, unlike normal cells, need significantly more glucose to grow and thrive. Restricting carbohydrate intake can significantly limit blood glucose and insulin, a hormone that has been shown in many independent studies to promote tumor growth in both humans and mice.Furthermore, a low-carbohydrate, high-protein diet has the potential to both boost the ability of the immune system to kill cancer cells and prevent obesity, which leads to chronic inflammation and cancer.

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