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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.

BEIJING, Aug. 12 (Xinhuanet) -- The risk of developing coronary heart disease is 25 percent higher for women smokers compared with men, according to a study published in the British medical journal "The Lancet".The authors say this could be due to the physiological differences between the sexes with cigarette smoke toxins having a more potent effect on women.The study by Dr Rachel R Huxley from the University of Minnesota and Dr Mark Woodward from Johns Hopkins University involved a meta-analysis of around four million individuals and 67,000 coronary heart disease events from 86 studies.The researchers found that the pooled adjusted female-to-male relative risk ratio (RRR) of smoking compared with not smoking for coronary heart disease (CHD) was 1.25 (25 percent) higher for women.This RRR increased by 2 percent for every additional year of follow-up, meaning that the longer a woman smokes, the higher her risk of developing CHD becomes compared with a man who has smoked the same length of time.The authors say, "The finding lends support to the idea of a pathophysiological basis for the sex difference. For example, women might extract a greater quantity of carcinogens and other toxic agents from the same number of cigarettes than men. This occurrence could explain why women who smoke have double the risk of lung cancer compared with their male counterparts."Worldwide, there are 1.1 billion smokers, of whom a fifth are women.According to the Tobacco Atlas, India, with around a crore female smokers, ranks third in the top 20 female smoking populations across the globe, only the U.S. with 2.3 crore female smokers and China with 1.3 crore female smokers, are worse off.

BEIJING, Aug. 26 (Xinhua) -- China's maritime authority on Friday once again urged U.S. oil giant ConocoPhillips to finish cleaning up oil spills in north China's Bohai Bay as soon as possible.Aug. 31 is the deadline set by the government. "There are only five days to go before the arrival of the deadline," said a statement of the State Oceanic Administration (SOA).The SOA urged ConocoPhillips China to adopt all technical measures that could be used to clean up oil spills, and to do it "with an active manner."Liu Cigui, head of the SOA, said Thursday that his administration is collecting evidence and gauging the ecological impact of the spills in preparation for possible legal action against the company.ConocoPhillips China, a subsidiary of ConocoPhillips, first reported the oil spills in June. The spills have spread to beaches in Hebei and Liaoning provinces and been blamed for losses in local tourism and aquatic farming industries.Although the company has worked to clean up the spills, pollutants have still been found in the bay, even after cleanup efforts were reported to be complete.ConocoPhillips China admitted that a total of 16 oil spill sources have been found in the bay as of Friday.

WASHINGTON, June 7 (Xinhua) -- Advanced hepatitis C patients with chronic liver disease may benefit from drinking coffee during treatment, according to a new study published Tuesday in Gastroenterology, the official journal of the American Gastroenterological Association Institute.The study shows that patients who received peginterferon plus ribavirin treatment and who drank three or more cups of coffee per day were two times more likely to respond to treatment than non- drinkers.Among non-drinkers, 46 percent had an early virologic response; 26 percent had no detectable serum hepatitis C virus (HCV) ribonucleic acid at week 20; 22 percent had no detectable serum at week 48; and 11 percent had a sustained virologic response. In contrast, the corresponding proportions for those who drank three or more cups of coffee per day were 73 percent, 52 percent, 49 percent and 26 percent, respectively."Coffee intake has been associated with a lower level of liver enzymes, reduced progression of chronic liver disease and reduced incidence of liver cancer," said Neal Freedman, of the National Cancer Institute and lead author of this study. "Although we observed an independent association between coffee intake and virologic response to treatment, this association needs replication in other studies."Approximately 70 to 80 percent of individuals exposed to HCV become chronically infected. Worldwide, these individuals are estimated to number between 130 and 170 million. Higher coffee consumption has been associated with slower progression of pre- existing liver disease and lower risk of liver cancer. However, the relationship with response to anti-HCV treatment had not been previously evaluated.

WASHINGTON, June 23 (Xinhua) -- NASA's next Mars rover has completed the journey from its California birthplace to Florida in preparation for launch this fall, the U.S. space agency said Thursday in a statement.The Mars Science Laboratory (MSL) rover, also known as Curiosity, arrived Wednesday at NASA's Kennedy Space Center aboard an Air Force C-17 transport plane. It was accompanied by the rocket-powered descent stage that will fly the rover during the final moments before landing on Mars.The rover's aeroshell -- the protective covering for the trip to the Red Planet -- and the cruise stage, which will guide it to Mars, arrived at Kennedy last month. The mission is targeted to launch from Cape Canaveral Air Force Station between Nov. 25 and Dec. 18. The car-size rover will land on Mars in August 2012.The rover and other spacecraft components will undergo more testing before mission staff stack them and fuel the onboard propulsion systems. Curiosity should be enclosed in its aeroshell for the final time in September and delivered to Kennedy's Launch Complex 41 in early November for integration with a United Launch Alliance Atlas V rocket.Curiosity is about twice as long and more than five times as heavy as any previous Mars rover. Its 10 science instruments include two for ingesting and analyzing samples of powdered rock delivered by the rover's robotic arm. During a prime mission lasting one Martian year -- nearly two Earth years -- researchers will use the rover's tools to study whether the landing region has had environmental conditions favorable for supporting microbial life and favorable for preserving clues about whether life existed.

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