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SINGAPORE, July 6 (Xinhua) -- A team of researchers in Singapore has designed a tube with special robotic hands that allows doctors to perform surgery on a patient's inner organs without resulting in scars, local media reported on Wednesday.The special "robotic hands" were fixed to the tube to access a patient's stomach. Compared with traditional methods which use only one robotic hand, the new device known as master and slave transluminal endoscopic robot, or MASTER, is more nimble, thereby allowing complex operations, the Lianhe Zaobao reported.Louis Phee, an associate professor at the Nanyang Technological University who led the team of researchers, had spent six years to develop the gadget, which cut an eight-hour procedure to just 17 minutes, said doctors at India's Asian Institute of Gastroenterology.The gadget, still in the trial stage, has been tested earlier this month on three patients at the Indian hospital. It is also expected to be tried out in Germany and China's Hong Kong later. The patients can leave the hospital much sooner than they would have using traditional gadgets.Phee said he expected the gadget to be available on the market as early as three years from now, after going through clinical trials and getting the approval from authorities.He also saw a potential for the gadget to be used on other organs by cutting a small spit on stomach that allows the gadget to go through to access the site.
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."
LOS ANGELES, July 22 (Xinhua) -- Two teams of astronomers have discovered the largest and farthest reservoir of water ever detected in the universe, NASA's Jet Propulsion Laboratory (JPL) said on Friday.The water, equivalent to 140 trillion times all the water in the world's ocean, surrounds a huge, feeding black hole, called a quasar, more than 12 billion light-years away, according to JPL in Pasadena, California."The environment around this quasar is very unique in that it's producing this huge mass of water," said Matt Bradford, a scientist at JPL. "It's another demonstration that water is pervasive throughout the universe, even at the very earliest times. "This artist's concept illustrates a quasar, or feeding black hole, similar to APM 08279+5255, where astronomers discovered huge amounts of water vapor. Gas and dust likely form a torus around the central black hole, with clouds of charged gas above and below. X-rays emerge from the very central region, while thermal infrared radiation is emitted by dust throughout most of the torus. While this figure shows the quasar's torus approximately edge-on, the torus around APM 08279+5255 is likely positioned face-on from our point of view.A quasar is powered by an enormous black hole that steadily consumes a surrounding disk of gas and dust. As it eats, the quasar spews out huge amounts of energy. Both groups of astronomers studied a particular quasar called APM 08279+5255, which harbors a black hole 20 billion times more massive than the sun and produces as much energy as a thousand trillion suns.Astronomers expected water vapor to be present even in the early, distant universe, but had not detected it this far away before. There's water vapor in the Milky Way, although the total amount is 4,000 times less than in the quasar, because most of the Milky Way's water is frozen in ice. Water vapor is an important trace gas that reveals the nature of the quasar. In this particular quasar, the water vapor is distributed around the black hole in a gaseous region spanning hundreds of light-years in size (a light-year is about six trillion miles).Its presence indicates that the quasar is bathing the gas in X- rays and infrared radiation, and that the gas is unusually warm and dense by astronomical standards, JPL said.Although the gas is at a chilly minus 63 degrees Fahrenheit ( minus 53 degrees Celsius) and is 300 trillion times less dense than Earth's atmosphere, it's still five times hotter and 10 to 100 times denser than what's typical in galaxies like the Milky Way, said JPL.Measurements of the water vapor and of other molecules, such as carbon monoxide, suggest there is enough gas to feed the black hole until it grows to about six times its size, JPL said.Whether this will happen is not clear, the astronomers say, since some of the gas may end up condensing into stars or might be ejected from the quasar.Bradford's team made their observations starting in 2008, using an instrument called "Z-Spec" at the California Institute of Technology's (Caltech's) Submillimeter Observatory, a 33-foot (10- meter) telescope near the summit of Mauna Kea in Hawaii. Follow-up observations were made with the Combined Array for Research in Millimeter-Wave Astronomy (CARMA), an array of radio dishes in the Inyo Mountains of Southern California.The second group, led by Dariusz Lis, senior research associate in physics at Caltech and deputy director of the Caltech Submillimeter Observatory, used the Plateau de Bure Interferometer in the French Alps to find water. In 2010, Lis's team serendipitously detected water in APM 8279+5255, observing one spectral signature.Bradford's team was able to get more information about the water, including its enormous mass, because they detected several spectral signatures of the water, according to JPL.
JOHANNESBURG, June 1 (Xinhua) -- An estimated 2 million adolescents ages 10 to 19 are living with HIV, with 86 percent of them from sub-Saharan Africa, according to a global report on HIV prevention launched in Johannesburg on Wednesday.For the first time, the world gets to see the number of adolescents between the ages of 10 to 19 living with HIV in the report named Opportunity in Crisis: Preventing HIV from early adolescence to young adulthood.The report is a jointly publication by the United Nations Children's Fund (UNICEF), UNAIDS, the United Nations Educational, Scientific and Cultural Organization (UNESCO), the United Nations Population Fund (UNFPA), the International Labor Organization (ILO) , the World Health Organization (WHO) and World Bank.According to the report, people aged 15-24 accounted for 41 percent of new infections over the age of 15 in 2009. Worldwide, an estimated 5 million young people in that age group were living with HIV in 2009. Most of them live in sub-Saharan Africa. Globally, young women make up more than 60 percent of all young people living with HIV. In sub-Saharan Africa that rate jumped to 72 percent.Despite these challenges, the report acknowledges that some progress has been made in preventing new infections among young people."In many high-burden countries, HIV prevalence and incidence have declined among young people. While in 2001 there were 5.7 million young people living with HIV, the figure stands at 5 million (in 2009)," said the UNICEF eastern and southern Africa regional director, Elhadj As Sy, at the media briefing.He pointed that sexual transmission and injection drug use remain the major modes of transmission of HIV among young people. Early sexual debut, early pregnancy and early experiences with drug use all raise risks for HIV infection.The report reveals that unemployment and poverty are reported as the main reasons young people enter the sex trade. Worldwide, many young people driven by economic pressure, exploitation, social exclusion and lack of family support turn to commercial sex and injecting drug use.In 2001, the world made a commitment to reduce the prevalence of HIV among young people by 25 percent by 2010. The actual reduction achieved (from 5.7 million to 5 million) is 12 percent, and it represents less than half the target percentage."To avoid the current programming failures, we have to adopt a ' Continuum of Prevention Approach'." said Lina Mousa, deputy director of UNFPA Africa Regional Office."This continuum of prevention must be reflected in national HIV strategic plans, poverty reduction strategies and global fund proposals. This response must be developed with and for young people so that they own the response together with their communities," she added.To build this continuum of prevention for adolescents and young people, the reports outlined nine specific recommendations including providing young people with information and comprehensive sexuality education, strengthening child protection and social protection measures, engaging communities in shaping a positive social environment that promotes healthy behavior, establishing laws and policies that respect young people's rights.
SAN FRANCISCO, June 28 (Xinhua) -- Google Android chief Andy Rubin said on Tuesday that the activations of Android-powered devices are growing at a rate of 4.4 percent on a weekly basis, with over 500,000 devices activated each day worldwide."There are now over 500,000 Android devices activated every day, and it's growing at 4.4 percent w/w," tweeted Rubin, Google's Senior Vice President of Mobile who oversees the development of Android, the open-source operating system for smartphones.Last month, Google said at its annual developer conference Google I/O that 400,000 Android devices were being activated each day, compared with 300,000 daily activations in December and 100, 000 in May 2010.More research data have shown Android system's soaring market share and popularity. Earlier this month, Internet market research company ComScore reported that Android remained the No. 1 smartphone operating system in the United States over the three months ending in April. The system captured 36.4 percent of U.S. smartphone subscribers, while Apple's iOS system for iPhone had 26 percent of all smartphone users.In April, market research company Gartner said in a forecast that the Android operating system will own 49.2 percent of the global smartphone market and Apple's iOS will have an 18.9-percent share in the second place.