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WASHINGTON, April 5 (Xinhua) -- NASA and co-researchers from the United States, the Republic of Korea and Japan have found a new mineral named "Wassonite" in one of the most historically significant meteorites recovered in Antarctica in December 1969, the U.S. space agency said on Tuesday in a statement.The new mineral was discovered within the meteorite officially designated Yamato 691 enstatite chondrite. The meteorite likely may have originated from an asteroid orbiting between Mars and Jupiter. Wassonite is among the tiniest, yet most important, minerals identified in the 4.5-billion-year-old sample.The research team, headed by NASA space scientist Keiko Nakamura-Messenger, added the mineral to the list of 4,500 officially approved by the International Mineralogical Association."Wassonite is a mineral formed from only two elements, sulfur and titanium, yet it possesses a unique crystal structure that has not been previously observed in nature," said Nakamura-Messenger.In 1969, members of the Japanese Antarctic Research Expedition discovered nine meteorites on the blue ice field of the Yamato Mountains in Antarctica. This was the first significant recovery of Antarctic meteorites and represented samples of several different types.As a result, the United States and Japan conducted systematic follow-up searches for meteorites in Antarctica that recovered more than 40,000 specimens, including extremely rare Martian and lunar meteorites.Researchers found Wassonite surrounded by additional unknown minerals that are being investigated. The mineral is less than one-hundredth the width of a human hair or 50x450 nanometers. It would have been impossible to discover without NASA's transmission electron microscope, which is capable of isolating the Wassonite grains and determining their chemical composition and atomic structure."More secrets of the universe can be revealed from these specimens using 21st century nano-technology," said Nakamura- Messenger.The new mineral's name was approved by the International Mineralogical Association. It honors John T. Wasson, professor at the University of California, Los Angeles. Wasson is known for his achievements across a broad swath of meteorite and impact research, including the use of neutron activation data to classify meteorites and to formulate models for the chemical makeup of bulk chondrites.

CARACAS, March 30 (Xinhua) -- The number of confirmed cases of the A/H1N1 influenza in Venezuela has risen to 482 this year, Health Minister Eugenia Sader said on Wednesday.According to the latest report, the state of Merida in southeastern Venezuela has 189 A/H1N1 influenza cases, the biggest number ever reported, which was followed by the Capital District of Caracas with 112 cases. The other 181 cases were confirmed in 17 of 24 Venezuelan states.The first case for this year was reported in Merida earlier this month.Sader said that the Venezuelan government was trying to prevent the spread of the disease. Some 3 million people have been vaccinated against the virus.Three patients infected with the A/H1N1 influenza virus have died in the country this year, according to Sader.The A/H1N1 influenza can cause deadly pneumonia if it is not treated early.

SAN FRANCISCO, April 25 (Xinhua) -- Oracle Corp. on Monday announced that its co-president Safra Catz is taking the additional position as the software giant's chief financial officer (CFO), following the resignation of its current CFO Jeff Epstein.Epstein was named Oracle's CFO in September 2008, and had reported directly to Catz. Oracle didn't give details about Epstein's departure.Catz joined Oracle in April 1999 and has been its president since January 2004. She previously served as the company's CFO from November 2005 to September 2008."Safra already has the long-standing confidence of our employees, our Board and our shareholders," Oracle's chief executive officer Larry Ellison said in a statement, adding that " there is no more logical choice for CFO.""The CFO function has reported to Safra for a number of years and she's acted as Oracle's CFO in the past. She has the full support of the Board," noted Jeff Henley, chairman of Oracle's board of directors.

WELLINGTON, May 13 (Xinhua) -- While it's long been known that a little sunshine can spread happiness, researchers in New Zealand have found that it can also save the lives of pneumonia patients.Medical scientists have found that vitamin D, which is absorbed through the skin and produced with exposure to sunlight, is a major factor in the survival rate of pneumonia patients.Researchers at Waikato University collaborated with doctors at Waikato Hospital, both Hamilton-based institutions, to study blood samples of 112 patients admitted to the hospital with pneumonia during the winter.They found that those with severe vitamin D deficiency 17 of the patients were more likely to die within a month, compared with patients with normal or slightly low vitamin D levels.Dr Bob Hancox, of the hospital's department of respiratory medicine, said five of the 17 died, a 29-percent mortality rate, compared with four deaths among the 95 patients with higher vitamin D levels, a 4-percent mortality rate."The analysis confirmed that the difference in mortality rates between the two groups was very unlikely to be due to chance," Hancox told Xinhua.Vitamin D deficiency was a concern around the world, Hancox said."Sunlight is the main source of vitamin D, so it tends to be a winter problem in temperate climates when people spend a lot of time indoors. But it occurs in all countries and vitamin D deficiency is believed to be a major problem worldwide."There is accumulating evidence that we need vitamin D to help fight infections, such as pneumonia as we have shown, as well as improve bone health," he told Xinhua."What is not yet clear is whether we can do anything about it. We don't know whether treating people with vitamin D supplements would help to prevent or treat respiratory infections. This is what we need to find out now."Dr Ray Cursons, of the Biological Sciences department at Waikato University, said patient age, sex, additional health conditions, and other prognostic factors did not affect the research outcome, although researchers still could not establish a causal link between vitamin D deficiency and mortality in the patients.Waikato Hospital D respiratory specialist Dr Noel Karalus said it was not yet known whether giving patients vitamin D supplements after their admission to hospital with respiratory tract infections would alter outcomes."It may transpire that vitamin D helps us avoid infection rather than cure it once established."Cursons said the best source of vitamin D was sunlight as dietary sources such as fatty fish and cod liver oil did not contain enough vitamin D."There is still some controversy regarding the optimal daily allowance of vitamin D. How much we absorb through the skin depends on sun exposure, skin type and geographical latitude. M ori and Pacific Islanders absorb less because of their darker skin, and people in colder climates also have lower levels of vitamin D. "Pneumonia is the single largest cause of death in children worldwide, killing an estimated 1.6 million children under the age of five each year, according to the World Health Organization.The research findings are published in the journal Respirology, published by the Asian Pacific Society of Respirology, this month.

LOS ANGELES, March 16 (Xinhua) -- The death rate in the United States reached an all-time low in 2009, dropping 2.3 percent from 2008, a newly released report said.This was the 10th straight year of decline, demonstrating that Americans are living longer than ever, according to the report from the U.S. Centers for Disease Control and Prevention's National Center for Health Statistics.The nation saw a drop from 758.7 deaths per 100,000 people in 2008 to 741 per 100,000 people in 2009 when 2,436,682 deaths were reported, said the report published by HealthDay News on Wednesday.However, life expectancy for blacks remained unchanged -- 70.9 years for men and 77.4 years for women. The disparity between whites and blacks is now 4.3 years, representing a 0.2 percent increase from 2008 to 2009, the report found.The report said that deaths fell in 10 of the 15 leading causes of death -- heart disease dropped 3.7 percent, cancer fell 1.1 percent, and stroke declined 4.2 percent.Deaths from Alzheimer's disease, diabetes, chronic lower respiratory diseases and accidents all declined 4.1 percent, according to the report.Deaths from flu and pneumonia fell 4.7 percent, and deaths from septicemia, a bacterial infection, decreased 1.8 percent, the report said.Deaths from homicides fell 6.8 percent, but suicides increased from 35,933 in 2008 to 36,547 in 2009. Other than suicide, which overtook septicemia as the 10th leading cause of death, the ranking of the leading causes of death was unchanged from 2008 to 2009, the report noted.Infant mortality hit a record low in 2009, falling from 6.59 deaths per 1,000 births in 2008 to 6.42, representing a 2.6 percent decrease, according to the report.The report, however, did not give reasons for these trends.Experts think behavioral changes, particularly the decline in smoking, are partly responsible for the improvements.The report's lead author Kenneth Kochanek, a statistician at the center, said this is preliminary data, and the final data, which should be available this summer, may shed some light on the findings.

来源：资阳报