梅州超导可视的人流(梅州可视打胎价格) (今日更新中)

WASHINGTON, July 5 (Xinhua) -- Intake of high levels of folate, a water-soluble B vitamin that occurs naturally in food, may reduce colorectal cancer risk, according to a new study published Tuesday in Gastroenterology, the official journal of the American Gastroenterological Association (AGA) Institute. "We found that all forms and sources of folate were associated with lower risk of colorectal cancer," said lead author Victoria Stevens, of the American Cancer Society. "The strongest association was with total folate, which suggests that total folate intake is the best measure to define exposure to this nutrient because it encompasses all forms and sources."Total folate includes naturally occurring food folate and folic acid from fortified foods and dietary supplements.The research team investigated the association between folate intake and colorectal cancer among 99,523 participants in the Cancer Prevention Study II Nutrition Cohort; a total of 1,023 participants were diagnosed with colorectal cancer between 1999 and 2007, a period entirely after folate fortification began. Neither higher nor lower risk was observed during the first two years of follow-up (1999 to 2001), while associations were statistically significantly inverse for the subsequent years (2002 to 2007). The findings of this study add to the epidemiologic evidence that high folate intake reduces colorectal cancer incidence.Folates are essential nutrients needed to make components used for functions required for normal cell growth, including DNA synthesis and repair. Because these processes are critical for cell growth and differentiation, the relationship between folate intake and cancer development has been investigated in several cancers, and most extensively in colorectal cancer.

MOSCOW, Aug. 24 (Xinhua) -- A Russian Progress cargo ship crashed into Siberia after failing to reach the right orbit Wednesday. The crash marked the second failure in space launch in less than a week and the third in this year, prompting local media to suspect a major reshuffle in Russia's space industry.UNPRECEDENTED FAILUREThe Progress M-12M unmanned freighter was launched to the International Space Station from Baikonur space center in Kazakhstan on Wednesday. It was expected to reach a near-Earth orbit in about nine minutes after launch.However, after the 325th second of the flight, which was just a few seconds before the vessel should reach the orbit, the ground control center lost it.Russian space agency Roscosmos confirmed later that the cargo ship failed to reach the orbit and fell down. Russian Progress M-12M cargo ship is launched to the International Space Station from Baikonur space center in Kazakhstan on Wednesday, Aug. 24, 2011. It has failed to reach the orbit, the Interfax news agency reported.The malfunction of the Soyuz-U rocket's engine was generally believed to be the cause of the accident, according to local media.A source in the space industry said the spaceship had sent a breakdown report while separating from the Soyuz rocket.Some unconfirmed reports said the fuel tank of the booster leaked and the engine was automatically turned off to avoid explosion.The wreckage of the Progress cargo ship has already fallen in southern Siberia's Altai Republic, where a big explosion was heard by locals, reported RIA Novosti news agency.A state investigation committee has been formed to look into the first ever loss of a Progress freighter.CONCERNS OVER FUTUREThe unprecedented accident raised concerns over the reserves of the six crew members on board the ISS.The ship was loaded with over 3.5 tons of supplies for the ISS, including scientific materials, oxygen, water and food.According to Russia's Ground Control, the loss of these supplies will not affect the ISS crew as there are enough stocks of necessities for two to three months.Also, there is no need for premature return of the crew, said Vladimir Solovyov, a space official.However, it still casts some shadow over the ISS program that relies on Russia exclusively following the retirement of U.S. shuttles.A source from the Russian space industry said the scheduled launches of the Soyuz rockets are likely to be suspended until the reasons of the accident are established.This means that current crew members of the ISS would likely stay longer in the space than planned, as the new members might not be able to replace them on schedule, the source explained. Solovyov said the launch of the next Progress is scheduled for October 28.So far, Roscosmos has refrained from comments regarding the possible halt in manned missions aboard Soyuz carrier rockets."Comments will follow. Now it is necessary to determine the causes of today's abortive launch of a Soyuz-u carrier rocket with the Progress M-2M transport ship," Roscosmos told Itar-Tass news agency.Local media raised the prospect of a major reshuffle in Russia' s space industry as the country has lost a total of six space vehicles over the past nine months.On Aug. 18, a carrier rocket Proton-M failed to deliver to the orbit communication satellite Express-AM4. Earlier in February, Russia had lost a satellite named Geo-IK2.In December 2010, a booster malfunction resulted in the loss of three satellites in the global positioning and navigation system GLONASS.

WASHINGTON, Sept. 15 (Xinhua) -- A team of researchers has discovered a planet that orbits around a pair of stars, the U.S. space agency NASA announced Thursday.This is the first instance of astronomers finding direct evidence of a so-called circumbinary planet. A few other planets have been suspected of orbiting around both members of a dual-star system, but the transits of the circumbinary planet have never been detected previously.The team, led by Laurance Doyle of the SETI Institute in California, used photometric data from the NASA Kepler space telescope, which monitors the brightness of 155,000 stars.NASA's Kepler mission has discovered a world where two suns set over the horizon instead of just one. The planet, called Kepler-16b, is the most "Tatooine-like" planet yet found in our galaxy. Tatooine is the name of Luke Skywalker's home world in the science fiction movie Star Wars. In this case, the planet it not thought to be habitable. It is a cold world, with a gaseous surface, but like Tatooine, it circles two stars.They found the binary star system by detecting a system where the stars eclipsed each other from the perspective of the Kepler spacecraft. These stars have two eclipses: A primary eclipse when the larger star is partially blocked by the smaller star and a secondary eclipse where the smaller star is fully blocked by the larger star.But the researchers also noticed other times when the brightness of the two stars dropped, even when they were not in an eclipse position. This pattern suggested that there was likely a third object involved. The fact that these so-called tertiary and quaternary eclipses recurred after varying intervals of time, and were of different depths, indicated that the stars were in different positions in their orbit at each instance. This result showed that the tertiary and quaternary eclipses were being caused by something circling both stars, and not an object circling one or the other star.Measurements of the variations in the timing of all four types of eclipses, resulting from the mutual gravitational interactions of the two stars and the third body, demonstrated that the third object was, indeed, a planet. Their work indicates that the planet is less massive than Jupiter, possibly comparable in mass to Saturn, and that the larger of the two binary stars is smaller than our Sun.Their findings will be published Friday in Science."This discovery confirms a new class of planetary systems that could harbor life," Kepler principal investigator William Borucki said in a statement. "Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars. This milestone discovery confirms a theory that scientists have had for decades but could not prove until now."

WASHINGTON, June 2 (Xinhua) -- When humans see red, their reactions become both faster and more forceful, according to a new study published this week in the U.S. bimonthly journal Emotion.The findings may have applications for sporting and other activities in which a brief burst of strength and speed is needed, such as weightlifting. But the authors caution that the color energy boost is likely short-lived.The study measured the reactions of students in two experiments. In the first, 30 fourth-through-10th graders pinched and held open a metal clasp. Right before doing so, they read aloud their participant number written in either red or gray crayon. In the second experiment, 46 undergraduates squeezed a handgrip with their dominant hand as hard as possible when they read the word "squeeze" on a computer monitor. The word appeared on a red, blue, or gray background.In both scenarios, red significantly increased the force exerted, with participants in the red condition squeezing with greater maximum force than those in the gray or blue conditions. In the handgrip experiment, not only the amount of force, but also the immediacy of the reaction increased when red was present.The colors in the study were precisely equated in hue, brightness, and chroma (intensity) to insure that reactions were not attributable to these other qualities of color."Red enhances our physical reactions because it is seen as a danger cue," explains coauthor Andrew Elliot, professor of psychology at the University of Rochester and a lead researcher in the field of color psychology. "Humans flush when they are angry or preparing for attack," he explains. "People are acutely aware of such reddening in others and it's implications."But threat is a double-edged sword, argue Elliot and coauthor Henk Aarts, professor of psychology at Utrecht University, in the Netherlands. Along with mobilizing extra energy, "threat also evokes worry, task distraction, and self-preoccupation, all of which have been shown to tax mental resources," they write in the paper.In earlier color research, exposure to red has proven counterproductive for skilled motor and mental tasks: athletes competing against an opponent wearing red are more likely to lose and students exposed to red before a test perform worse.

SAN FRANCISCO, Aug. 22 (Xinhua) -- Hewlett-Packard (HP) on Monday unveiled a new business desktop computer, days after the world's largest personal computer (PC) maker announced its plan to sell its PC business.The company said the new model, HP Compaq 8200 Elite All-in-One Business Desktop, is the industry's first all-in-one PC that integrates Intel's second-generation Core vPro technology, which can deliver up to 40 percent better performance, 15 percent faster hard drive access and reduced downtime via remote information technology management."Another industry first in our Elite desktop family demonstrates our commitment to engineering excellence and underscores our global leadership in secure, enterprise computing, " Jeff Groudan, HP's director of commercial desktop marketing, said in a statement.HP said the new computer is available now in the United States. It starts at the price of 999 U.S. dollars, and comes with a standard three-year warranty.Last Thursday the company announced that it is considering a full or partial separation of its PC business through a spin-off or other transactions, a process that HP estimates may take about 12 to 18 months.

来源：资阳报