太原眼球解剖放大模型(乌鲁木齐动脉立体结构模型) (今日更新中)

WASHINGTON, May 4 (Xinhua) -- The U.S. National Aeronautics and Space Administration (NASA) announced Wednesday that its Gravity Probe B (GP-B) mission has confirmed two key predictions derived from Albert Einstein's general theory of relativity, which the spacecraft was designed to test.The experiment, launched in 2004, used four ultra-precise gyroscopes to measure the hypothesized geodetic effect, the warping of space and time around a gravitational body, and frame- dragging, the amount a spinning object pulls space and time with it as it rotates.GP-B determined both effects with unprecedented precision by pointing at a single star, IM Pegasi, while in a polar orbit around Earth. If gravity did not affect space and time, GP-B's gyroscopes would point in the same direction forever while in orbit. But in confirmation of Einstein's theories, the gyroscopes experienced measurable, minute changes in the direction of their spin, while Earth's gravity pulled at them.The findings are available online in the journal Physical Review Letters."Imagine the Earth as if it were immersed in honey. As the planet rotates, the honey around it would swirl, and it's the same with space and time," said Francis Everitt, GP-B principal investigator at Stanford University. "GP-B confirmed two of the most profound predictions of Einstein's universe, having far- reaching implications across astrophysics research."GP-B is one of the longest running projects in NASA history, with agency involvement starting in the fall of 1963 with initial funding to develop a relativity gyroscope experiment. Subsequent decades of development led to groundbreaking technologies to control environmental disturbances on spacecraft, such as aerodynamic drag, magnetic fields and thermal variations. The mission's star tracker and gyroscopes were the most precise ever designed and produced.GP-B completed its data collection operations and was decommissioned in December 2010."The mission results will have a long-term impact on the work of theoretical physicists," said Bill Danchi, senior astrophysicist and program scientist at NASA Headquarters in Washington. "Every future challenge to Einstein's theories of general relativity will have to seek more precise measurements than the remarkable work GP-B accomplished."

ISTANBUL, May 3 (Xinhua) -- The world's water consumption will increase by 40 percent over the next two decades and efforts to meet this demand must increase radically, the secretary-general of the 5th World Water Forum said here on Tuesday.Oktay Tabasaran said in his opening speech at the World Water Forum that "water consumption will increase by 40 percent in the coming 20 years, reaching 6.9 trillion cubic meters per year ( compared with the 4.5 trillion used currently), and an amount of 200 billion U.S. dollars must be spent annually in order to afford this."He said such figures indicated the urgent need for countries to engage in efficient cooperation with each other to address water- related issues.Some 50 out of the world's 188 countries have serious concerns in providing drinking and irrigation water, due to careless and inefficient use of water, according to Ismail Ugur, the general director of Turkey's State Waterworks Authority."If we fail to come up with solutions, starting from 2015 there will be droughts (in many parts of the world) and people will start suffering from diseases caused by lack of water, as of 2025, " Ugur said.Ekmeleddin Ihsanoglu, head of the Organization of the Islamic Conference (OIC), said that ensuring reliable access to water is crucial to promoting peace and security in the Middle East, where many countries are facing dramatic declines in available water."In some regions of the Muslim world, water availability is predicted to be cut in half by 2050, even without taking into consideration the effects of climate change," he said in his opening speech.The OIC chief called for increased cooperation among member states and countries outside the region, announcing the group's progress in preparing its own "Water Vision" document and forming an OIC Water Council to address water-related concerns."In its first phase, the Water Vision will outline a framework of cooperation on water-related issues in terms of water-sharing experience, capacity development, technology transfer, water governance and institutional reforms," Ihsanoglu said.He cited the Friendship Dam, to be constructed on the Orontes River at the Turkish-Syrian border, as an excellent example of cooperation and peace among neighboring countries in the field of water.Charity Ngilu, minister for water and irrigation of Kenya, stressed the importance of water in promoting peace, especially in regions where water scarcity prevails."There have been many conflicts caused by water scarcity not only among African countries, but even within regions of the same country," She said, adding Kenya would ask Turkey for cooperation and assistance in water management and other related issues.

WASHINGTON, March 24 (Xinhua) -- The U.S. Food and Drug Administration (FDA) on Thursday approved the use of Zostavax, a live attenuated virus vaccine, for the prevention of shingles in individuals 50 to 59 years of age. Zostavax is already approved for use in individuals 60 years of age and older.In the United States shingles affects approximately 200,000 healthy people between the ages of 50 and 59, per year. It is a disease caused by the varicella-zoster virus, which is a virus in the herpes family and the same virus that causes chickenpox.After an attack of chickenpox, the virus lies dormant in certain nerves in the body. For reasons that are not fully understood, the virus can reappear in the form of shingles, more commonly in people with weakened immune systems and with aging."The likelihood of shingles increases with age. The availability of Zostavax to a younger age group provides an additional opportunity to prevent this often painful and debilitating disease" said Karen Midthun, director of FDA's Center for Biologics Evaluation and Research, in a statement. ( Shingles is characterized by a rash of blisters, which generally develop in a band on one side of the body and can cause severe pain that may last for weeks, and in some people, for months or years after the episode.Approval was based on a multicenter study conducted in the United States and four other countries in approximately 22,000 people who were 50-59 years of age. Half received Zostavax and half received a placebo. Study participants were then monitored for at least one year to see if they developed shingles. Compared with placebo, Zostavax reduced the risk of developing shingles by approximately 70 percent.The most common side effects observed in the study were redness, pain and swelling at the site of injection, and headache, according to the FDA.Zostavax, manufactured by Merck & Co., was originally approved on May 26, 2006, for the prevention of shingles in individuals 60 years of age and older.

BEIJING, Feb. 13 (Xinhua) -- Snow fell again in Beijing Saturday night, three days after the city had its first snow this winter.Snow continued falling on Sunday morning but was forecasted to stop in the daytime.From 8:00 p.m. Saturday to 8:00 a.m. Sunday, precipitation in Beijing averaged 1.7 mm to 3.1 mm in downtown areas, local meteorologists said.Zhang Qiang, head of the municipal artificial weather intervention office, said the office began cloud seeding and was continuing efforts to increase snowfall from 7:25 p.m. Saturday in the nine districts and counties of Miyun, Mentougou, Yanqing, Haidian, Pinggu, Changping, Shijingshan, Fangshan and Huairou.By 8:20 a.m. Sunday, 657 silver iodide rods had been used to increase the snowfall.More than 3,583 people and 768 vehicles have been mobilized since Saturday to clear the snow on major roads of Beijing to ensure road transportation, according to the city transportation departments.Beijing had its first snow of the winter Wednesday and Thursday after 108 days of zero precipitation.Meteorologists said the snowfall in Beijing had helped ease the pressure of drought."Beijing is expected to have another cold front from Feb. 15 to Feb. 16, but it is not sure if there will be another snowfall then," said Liao Xiaonong, chief weatherman with the Beijing Meteorological Bureau.

CHANGSHA, Jan. 25 (Xinhua) -- More than 8,000 fake goods were destroyed Tuesday in central China's Hunan Province, as part of Chinese efforts to protect intellectual property rights (IPR).Supervised by Changsha customs official, trucks rolled over a huge pile of counterfeit electronic devices in the city, the provincial capital.The trucks crashed imitation Nokia, Motorola and Apple laptop computers, cell phones, earphones and compact discs.Pirated books and Gucci handbags were incinerated.Changsha customs have confiscated more than 34,000 fake items worth 1.3 million yuan (197,470 U.S. dollars) over the past two years, said Liu Zili, a customs official.Some confiscated fake goods were donated to Red Cross societies and quake-devastated regions, in accordance with China's IPR protection regulations.

来源：资阳报