专业的昌吉流产医院(昌吉测怀孕多久能测出来) (今日更新中)

WASHINGTON, May 11 (Xinhua) -- NASA's Dawn spacecraft has obtained its first image of the giant asteroid Vesta, which will help fine-tune navigation during its approach, the U.S. space agency announced Wednesday.Dawn expects to achieve orbit around Vesta on July 16, when the asteroid is about 117 million miles from Earth.The image from Dawn's framing cameras was taken on May 3 when the spacecraft began its approach and was approximately 752,000 miles (1.21 million km) from Vesta. The asteroid appears as a small, bright pearl against a background of stars. Vesta also is known as a protoplanet, because it is a large body that almost formed into a planet."After plying the seas of space for more than a billion miles, the Dawn team finally spotted its target," said Carol Raymond, Dawn's deputy principal investigator at NASA's Jet Propulsion Laboratory in Pasadena, California. "This first image hints of detailed portraits to come from Dawn's upcoming visit."Vesta is 330 miles (530 km) in diameter and the second most massive object in the asteroid belt. Ground- and space-based telescopes obtained images of the bright orb for about two centuries, but with little surface detail.Mission managers expect Vesta's gravity to capture Dawn in orbit on July 16. To enter orbit, Dawn must match the asteroid's path around the sun, which requires very precise knowledge of the body's location and speed. By analyzing where Vesta appears relative to stars in framing camera images, navigators will pin down its location and enable engineers to refine the spacecraft's trajectory.Dawn will start collecting science data in early August at an altitude of approximately 1,700 miles (2,700 km) above the asteroid's surface. As the spacecraft gets closer, it will snap multi-angle images allowing scientists to produce topographic maps. Dawn will later orbit at approximately 120 miles (200 km) to perform other measurements and obtain closer shots of parts of the surface. Dawn will remain in orbit around Vesta for one year. After another long cruise phase, Dawn will arrive in 2015 at its second destination, Ceres, an even more massive body in the asteroid belt.Gathering information about these two icons of the asteroid belt will help scientists unlock the secrets of our solar system's early history. The mission will compare and contrast the two giant asteroids shaped by different forces. Dawn's science instruments will measure surface composition, topography and texture. Dawn also will measure the tug of gravity from Vesta and Ceres to learn more about their internal structures. The spacecraft's full odyssey will take it on a 3-billion-mile (5-billion-km) journey, which began with its launch in September 2007.

WASHINGTON, March 4 (Xinhua) -- New data suggest that the epilepsy drug Topamax (topiramate) and its generic versions increase the risk for the birth defects cleft lip and cleft palate in babies born to women who use the medication during pregnancy, the U.S. Food and Drug Administration (FDA) said Friday in a statement.Before prescribing topiramate, approved to treat certain types of seizures in people who have epilepsy, health care professionals should warn patients of childbearing age about the potential hazard to the fetus if a woman becomes pregnant while using the drug, the FDA said.Topiramate also is approved to prevent migraine headaches, but not to relieve the pain of migraines."Health care professionals should carefully consider the benefits and risks of topiramate when prescribing it to women of childbearing age," said Russell Katz, director of the Division of Neurology Products in the FDA's Center for Drug Evaluation and Research. "Alternative medications that have a lower risk of birth defects should be considered."Cleft lip and cleft palate, collectively called oral clefts, are birth defects that occur when parts of the lip or palate do not completely fuse together early in the first trimester of pregnancy, a time when many women do not know they are pregnant.The defects range from a small notch in the lip to a groove that runs into the roof of the mouth and nose, possibly leading to problems with eating, talking, and to ear infections. Surgery often is performed to close the lip and palate and most children do well after treatment.Data from the North American Antiepileptic Drug (AED) Pregnancy Registry indicate an increased risk of oral clefts in infants exposed to topiramate during the first trimester of pregnancy. Infants exposed to topiramate as a single therapy experienced a 1.4 percent prevalence of oral clefts, compared with a prevalence of 0.38 percent - 0.55 percent in infants exposed to other antiepileptic drugs.Infants of mothers who did not have epilepsy and were not being treated with other antiepileptic drugs had a prevalence of 0.07 percent. Similar data from the United Kingdom Epilepsy and Pregnancy Register supported the North American AED Pregnancy Registry data.According to the FDA, before starting topiramate, pregnant women and women of childbearing potential should discuss other treatment options with their health care professional.

BEIJING, April 19 (Xinhuanet) -- The case in the Hollywood blockbuster "The Social Network" continues in real life.Twins Cameron and Tyler Winklevoss on Monday filed another appeal against their Harvard classmate and Facebook founder Mark Zuckerberg.The Winklevosses claim that the case needs to be reviewed by a special 11-judge panel in the latest appeal, after a three-judge panel of the 9th U.S. Circuit Court of Appeals ruled against the brothers last week.The twins initially claimed that Zuckerberg had stolen their idea for the website but agreed to drop their lawsuit in 2008 in exchange for 20 million dollars in cash and stock in the company.But later they discovered the stock was worth less than claimed at the time and sought to have the deal voided, the brothers said.

BRASILIA, March 15 (Xinhua) -- A nationwide program aimed at providing internet access to 80 percent of the country's population by 2014 is forging ahead in Brazil, Communications Minister Paulo Bernardo said on Tuesday.The National Broadband Plan (PNBL), with participation of 13 ministries, is coordinated by Bernardo, who explained details about the project on Tuesday along with Joao Santana, president of Telebras, the state-owned enterprise responsible for managing the project.The authorities have criticized companies that offer internet service for failing to spread internet use in Brazil, offering an expensive service with prices amounting to about 50 U.S. dollars monthly, inaccessible to low-income families."We ended 2010 with 34 percent of Brazilian households with Internet access, and service is also very poor. Almost half of connections are of 256 mbps. We are out-of-date, with the aggravating circumstance that the connections are very expensive," Bernardo said.To speed up the process, the government started negotiating with concessionaire phone companies to improve the service quality and lower the price to about 30 reais (18 dollars), which would allow 80 percent of the population to access internet."During (former president) Lula da Silva's government, we developed a program to interconnect all schools with internet access, but we also want the private sector to do its share," he said.

SAN FRANCISCO, May 26 (Xinhua) -- Internet advertising revenues in the United States surged to 7.3 billion U.S. dollars in the first quarter of 2011, the highest first-quarter revenue level on record for the industry, said a new report released on Thursday.The numbers also represented a 23-percent increase over the same period a year earlier, the Interactive Advertising Bureau ( IAB) and PricewaterhouseCoopers said in the report."The consistent and considerable year-over-year growth we're seeing demonstrates that digital media is an increasingly popular destination for ad dollars, and for good reason," Randall Rothenberg, chief executive officer of the IAB, said in a statement."As Americans spend more time online for information and entertainment purposes, digital advertising and marketing has emerged as one of the most effective tools businesses have to attract and retain customers," he added."These numbers indicate that the interactive advertising field hasn't simply bounced back since the recession; it's growing with dynamic energy," noted David Silverman, a partner at PricewaterhouseCoopers.IAB, a trade association for interactive marketing, comprised more than 500 media and technology companies who are responsible for selling 86 percent of online advertising in the United States.

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