银川八字算命谁准厉害(乌海算命需要多少钱) (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."

LOS ANGELES, April 18 (Xinhua) -- Sugarcane has the effect of cooling temperatures, thus playing role in stemming global warming, a new study has found.Sugarcane does so by reflecting sunlight back into space and by lowering the temperature of the surrounding air as the plants " exhale" cooler water, according to the study conducted by researchers at the Carnegie Institution's Department of Global Ecology.The researchers used data from hundreds of satellite images over 733,000 square miles (about 1,173 square kilometers) in Brazil, where sugarcane is widely grown. They measured temperature, reflectivity (also called albedo), and evapotranspiration -- the water loss from the soil and from plants as they exhale water vapor.The findings showed that expansion of sugarcane in areas previously occupied by other Brazilian crops cools the local climate.Converting from natural vegetation to crop/pasture on average warmed the cerrado by 2.79 Fahrenheit (1.55 Centigrade, but that subsequent conversion to sugarcane, on average, cooled the surrounding air by 1.67 Fahrenheit (0.93 Centigrade), the researchers said in the study published in the April issue of Nature Climate Change."We found that shifting from natural vegetation to crops or pasture results in local warming because the plants give off less beneficial water. But the bamboo-like sugarcane is more reflective and gives off more water -- much like the natural vegetation," said lead researcher Scott Loarie. "It's a potential win-win for the climate -- using sugarcane to power vehicles reduces carbon emissions, while growing it lowers the local air temperature."Brazilians are world leaders in using biofuels for gasoline. About a quarter of their automobile fuel consumption comes from sugarcane, which significantly reduces carbon dioxide emissions that otherwise would be emitted from using gasoline.The researchers emphasized that the beneficial effects are contingent on the fact sugarcane is grown on areas previously occupied by crops or pastureland, and not in areas converted from natural vegetation. It is also important that other crops and pastureland do not move to natural vegetation areas, which would contribute to deforestation.So far most of the thinking about ecosystem effects on climate considers only impacts from greenhouse gas emissions. But according to co-researcher Greg Asner, "It's becoming increasingly clear that direct climate effects on local climate from land-use decisions constitute significant impacts that need to be considered core elements of human-caused climate change."

BEIJING, May 19 (Xinhuanet) -- Google on Wednesday began fixing a security hole in some 97 percent of Android phones that could let hackers snatch important credentials at public WiFi hotspots.The fix, which addresses a hole allowing hackers to access the contacts, calendars and photos on an Android phone connected to an open WiFi network, will take a few days to cover every phone, a Google spokesman said.Unlike a traditional software update, the problem exists on Google's servers, so Android users won't need to manually take action.The newest versions of Android, including the new wave of tablets running its Honeycomb software, are not affected by the bug, according to the researchers at Germany's University of Ulm who initially reported the issue.The vulnerability could also cause devices synchronizing with Google Picasa web albums to transmit sensitive data through unencrypted channels, the researchers added.The Google spokesman said the company's security team is still investigating those claims.

XICHANG, Sichuan, April 10 (Xinhua) -- China early Sunday morning successfully launched its eighth orbiter which will form part of its indigenous satellite-navigation and -positioning network.A Long March-3A carrier rocket carrying the "Beidou," or Compass, navigation satellite took off at 4:47 a.m. Sunday from the Xichang Satellite Launch Center in southwest China's Sichuan Province.It will join seven other satellites already in orbit to form a network which will eventually consist of more than 30 satellites.The launching of the satellite marks the establishment of a basic system for the navigation and positioning network, said an unidentified spokesperson for the Xichang Satellite Launch Center.China will launch more satellites within the coming two years to finish a regional network to provide navigation services with high precision and credibility for industries and sectors such as mapping, fishery, transportation, meteorology and telecommunication, in the Asia-Pacific regions, the spokesperson said.The network is scheduled to be able to provide global services by 2020.

WASHINGTON, April 4 (Xinhua) -- New research from the University of Pennsylvania School of Medicine has revealed an increased incidence of major adverse cardiac events (MACE), such as heart attack, stroke, and cardiovascular death, in patients with severe psoriasis. The study results were reported Monday at the annual American College of Cardiology meeting in New Orleans.Psoriasis is a common inflammatory skin disease, and if severe, has been demonstrated to be a risk factor for cardiovascular disease. However, the degree to which psoriasis is associated with MACE has not been defined.In a cohort study analyzing data from a general practice research database, Lead author Nehal Mehta, director of Inflammatory Risk in Penn's Preventive Cardiology program, and colleagues reviewed the case histories of over 3,600 patients with severe psoriasis and 14,300 controls. They found that patients with severe psoriasis have a 53 percent increased incidence of MACE compared to the general population. They also found that having a diagnosed case of severe psoriasis confers an additional ten-year risk of six percent on MACE.Previous work from Mehta and colleagues found that the risk of death from cardiovascular disease increased by 57 percent in patients with severe psoriasis. In addition, the relative risk of death from cardiovascular disease was even higher in younger patients, who were as young as age 40.The researchers conclude that this new estimate of increased ten-year MACE may warrant more aggressive strategies for treatment of cardiovascular risk factors in patients with psoriasis.

来源：资阳报