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问答题Once the exclusive domain of executives with expense accounts, mobile phones are set to become one of the central technologies of the 21st century. (46) Within a few years, the mobile phone will evolve from a voice-only device to a multi-functional communicator capable of transmitting and receiving not only sound, but video, still images, data and text. A whole new era of personal communication is on the way. Thanks in part to the growth of wireless networks, the telephone is converging with the personal computer and the television. (47) Soon light-weight phones outfitted with high resolution screens--which can be embedded in everything from wristwatches to palm-held units will be connected to series of low orbit satellites enabling people to talk, send and receive E-mail, or take part in video conferences anytime, anywhere. These phones might also absorb many of the key functions of the desktop computer. Mobile devices are expected to be ideal for some of the new personalized services that are becoming available via the Internet. The communications revolution is already taking shape around the globe. In Europe, mall-scale trials are under way using mobile phones for electronic commerce. For example, most phones contain a subscriber identification module (SIM) card that serves primarily to identify a user to the phone network. Some manufacturers plan to upgrade the SIM card to an all-in-one personal identification and credit card. Another approach is to add a slot to mobile phones for a second smart card designed specifically for mobile ecommerce. (48) These cards could be used to make payments over the Internet or removed from the phone for use in point of-sale terminals to pay for things like public transportation, movie tickets or a round of drinks at the bar. In France, Motorola is currently testing a dual slot phone, the Star TACD, in a trial with France Telecom while in Finland Nokia is testing a phone that uses a special plug in reader for a tiny smart card. Siemens is pursuing a different approach. (49) Since it is not very clear whether it's best to do everything with a single device, Siemens is developing dual slot phones and Einstein, a device equipped with a smart card reader and keypad that can be linked to the phone via infrared wireless technology. (50) For those who want to, though, it will be possible to receive almost all forms of electronic communication through a single device, most likely a three-in-one phone that serves as a cordless at home, a cell phone on the road and an intercom at work. "The mobile phone will become increasingly multifunctional," says Burghardt Schallenberger, vice president for technology and innovation at Siemens Information and Consumer Products.

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问答题(46) It is known that the brain shrinks as the body ages, but the effects on mental ability are different from person to person. Interestingly, in a study of elderly men and women, those who had more education actually had more brain shrinkage. "That may seem like bad news," said study author Dr. Edward Coffey, a professor of psychiatry and of neurology at Henry Ford Health System in Detroit. (47) However, he explained, the finding suggests that education allows people to withstand more brain tissue loss before their mental functioning begins to break down. The study, published in the July issue of Neurology, is the first to provide biological evidence to support a concept called the "reserve" hypothesis, according to the researchers. In recent years, investigators have developed the idea that people who are more educated have greater cognitive reserves to draw upon as the brain ages; in essence, they have more brain tissue to spare. (48) Examining brain scans of 320 healthy men and women aged 66 to 90, researchers found that for each year of education the subjects had, there was greater shrink age of the outer layer of the brain known as the cortex. Yet on tests of cognition and memory, all participants scored in the range indicating normal. "Everyone has some degree of brain shrinkage," Coffey said. "People lose (on average) 2.5 percent per decade starting in adulthood." There is, however, a "remarkable range "of shrinkage among people who show no signs of mental decline, Coffey noted. Overall health, he said, accounts for some differences in brain size. Alcohol or drug use, as well as medical conditions such as diabetes and high blood pressure, contribute to brain tissue loss throughout adulthood. In the absence of such medical conditions, Coffey said, education level helps explain the range of brain shrinkage exhibited among the mentally-fit elderly. The more-educated can withstand greater loss. (49) Coffey and colleagues gauged shrinkage of the cortex by measuring the cerebrospinal fluid surrounding the brain. The greater the amount of fluid, the greater the cortical shrinkage. Controlling for the health factors that contribute to brain injury, the researchers found that education was related to the severity of brain shrinkage. For each year of education from first grade on, subjects had an average of 1.77 milliliters 11 more cerebrospinal fluid around the brain. Just how education might affect brain cells is unknown. (50) In their report, the researchers speculated that in people with more education, certain brain structures deeper than the cortex may stay intact to compensate for cortical shrinkage.

问答题The produce departments of the future may look like nothing on earth, and with good reason. Chinese scientists have been growing tomatoes the size of softballs, cucumbers as long as baseball bats and other outsize fruits and vegetables, using seeds that have been shot into space. The seeds are then exposed to seven types of extraterrestrial conditions, from zero gravity and cosmic radiation to subatomic particles. (46) As these space veggies grow back on earth, they are selected for desirable traits--bulk, appearance or certain nutrients--then bred through successive generations to ensure that the mutations are consistent. Chinese scientists don't understand exactly how a trip into space alters the seeds' DNA and yields such effects, but it's not just size that changes. (47) Tong Yichao, whose firm, the Beijing Flying Eagle Green Foods Group, has been sending seeds and seedlings aboard Chinese spacecraft since 1999, says it has grown space tomatoes with 27 percent more of the antioxidant beta carotene than ordinary ones, and six-foot-tall cotton plants that produce longer, more flexible threads. Using conventional methods, "a scientist might create just three new plants in his lifetime," says Tong. "We've developed more than 50 since 1999." (48) A dozen or so Chinese firms are paying up to $ 45 000 a gram to place various flora aboard satellites and manned spacecraft. The long-term goal: to feed more people and help endangered species escape extinction. To date, nearly 3 000 botanical species-including garden vegetables, medicinal herbs and flowers--have been sent into orbit and brought back to earth. (49) The commercial promise of China's space veggies has yet to, er, bear fruit. It' s legal to sell the cosmic produce, and commercial farms have purchased some space plants. But most are being developed in labs or experimental greenhouses because no one wants to go to market before the safety and quality of the produce have been established. Even so, the idea of space flora is proving irresistible to a novelty-loving Chinese public. (50) When Tong displayed a handful of monster space eggplants--the largest of which weighed more than four pounds--at an expo, one disappeared before the show opened. Hot stuff, for sure.

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问答题(46) "Popular art" has a number of meanings, impossible to define with any precision, which range from folklore to junk, with poles being clear enough but the middle tending to blur. The Hollywood Western of the 1930's, for example, has elements of folklore, but is closer to junk than to high art or folk art. There can be great trash, just as there is bad high art. The musicals of George Gershwin are great popular art, never aspiring to high art. Schubert and Brahms, however, used elements of popular music—folk themes—in works clearly intended as high art. The case of Verdi is a different one: he took a popular genre—bourgeois melodrama set to music (an accurate definition of nineteenth-century opera)—and, without altering its fundamental nature, transmuted it into high art. (47) This remains one of the greatest achievements in music, and one that cannot be fully appreciated without recognizing the essential trashiness of the genre. As an example of such a transmutation, consider what Verdi made of the typical political elements of nineteenth-century opera. (48)Generally in the plots of these operas, a hero or heroine—usually portrayed only as an individual, unrestrained by class—is caught between the immoral corruption of the aristocracy and the doctrinaire rigidity of the leaders of the civilians. Verdi transforms this naive and unlike formulation with music of extraordinary energy and rhythmic vitality, music more subtle than it seems at first hearing. There are scenes and arias that still sound like calls to arms and were clearly understood as such when they were first performed. Such pieces lend an immediacy to the otherwise veiled political message of these operas and call up feelings beyond those of the opera itself. Or consider Verdi's treatment of character. (49) Before Verdi, there were rarely any characters at all in musical drama, only a series of situations which allowed the singers to express a series of emotional state. Any attempt to find coherent psychological portrayal in these operas is misplaced ingenuity. The only coherence was the singer's vocal technique: when the cast changed, new arias were almost always substituted, generally adapted from other operas. Verdi's characters, on the other hand, have genuine consistency and integrity, even if, in many cases, the consistency is that of pasteboard melodrama. The integrity of the character is achieved through the music: (50) once he had become established, Verdi did not rewrite his music for different singers or allow alterations or substitutions of somebody else's arias in one of his operas, as every eighteenth-century composer had done. When he revised an opera, it was only for dramatic economy and effectiveness.

问答题It doesn't take an Einstein to recognize that Albert Einstein's brain was very different from yours and mine. (46) The gray matter housed inside that shaggy head managed to revolutionize our concepts of time, space, motion--the very foundations of physical reality--not just once but several times during his astonishing career. Yet while there clearly had to be something remarkable about Einstein's brain, the pathologist who removed it from the great physicist's skull after his death reported that the organ was, to all appearances, well within the normal range-no bigger or heavier than anyone else's. But a new analysis of Einstein's brain by Canadian scientists, reported in the current Lancet, reveals that it has some distinctive physical characteristics after all. (47) A portion of the brain that governs mathematical ability and spatial reasoning--two key ingredients to the sort of thinking Einstein did best--was significantly larger than average and may also have had more interconnections among its cells, which could have allowed them to work together more effectively. In 1996, Harvey gave much of his data and a significant fraction of the tissue itself to Dr. Sandra Witelson, a neuroscientist who maintains a "brain bank" at McMaster for comparative studies of brain structure and function. (48) These normal, undiseased brains, willed to science by people whose intelligence had been carefully measured before death, gave Witelson a solid set of benchmarks against which to measure the seat of Einstein's brilliant thoughts. Not only was Einstein's inferior parietal region unusually bulky, the scientists found, but a feature called the Sylvian fissure was much smaller than average. (49) Without this groove that normally slices through the tissue, the brain cells were packed close together, permitting more interconnections--which in principle can permit more cross- referencing of information and ideas--leading to great leaps of insight. That's the idea, anyway. But while it's quite plausible according to current neurological theory, that doesn't necessarily make it true. We know Einstein was a genius, and we now know that his brain was physically different from the average. But none of this proves a cause-and-effect relationship. "What you really need," says McLean's Benes, "is to look at the brains of a number of mathematical geniuses to see if the same abnormalities are present. " (50) Even if they are, it's possible that the bulked-up brains are a result of strenuous mental exercise, not an inherent feature that makes genius possible. Bottom line: we still don't know whether Einstein was born with an extraordinary mind or whether he earned it, one brilliant idea at a time.

问答题Directions:Writeanessayof160～200wordsbasedonthefollowingdrawings.Inyoushould:1)describethedrawingbriefly,2)interpretthephenomenonreflectedbyit,andthen3)giveyourcomments.YoushouldwriteneatlyonANSWERSHEET2.

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