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考博英语
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单选题Floods cause billions of dollars worth of property damage______. A. relatively B. actually C. annually D. comparatively
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单选题To compensate for the substantial decline in the availability of fossil fuels in future years, we will have to provide at least an ______ alternative energy source.
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单选题 It is believed that the Black Death, rampant in the Medieval Europe ______, killed 1/3 of its population.
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单选题He was very______ to go, but he had no choice.
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单选题Telecommuting--substituting the computer for the trip to the job--has been ______ a solution to all kinds of problems related to office work. A. hailed as B. drawn out C. borne out D. lodged in
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单选题{{B}}Part A{{/B}}There are three reading passages in this part. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice and mark the corresponding letter on the Answer Sheet with a single line through the center. If there is one thing scientists have to hear, it is that the game is over. Raised on the belief of an endless voyage of discovery, they recoil (畏缩) from the suggestion that most of the best things have already been located. If they have, today' s scientists can hope to contribute no more than a few grace notes to the symphony of science. A book to be published in Britain this week, The End of Science, argues persuasively that this is the case. Its author, John Horgan, is a senior writer for Scientific American magazine, who has interviewed many of today's leading scientists and science philosophers. The shock of realizing that science might be over came to him, he says, when he was talking to Oxford mathematician and physicist Sir Roger Penrose. The End of Science provoked a wave of denunciation (谴责) in the United States last year. "The reaction has been one of complete shock and disbelief," Mr. Horgan says. The real question is whether any remaining unsolved problems, of which there are plenty, lend themselves to universal solutions. If they do not, then the focus of scientific discovery is already narrowing. Since the triumphs of the 1960s--the genetic code, plate tectonics (板块构造税), and the microwave background radiation that went a long way towards proving the Big Bang--genuine scientific revolutions have been scarce. More scientists are now alive, spending more money on research, than ever. Yet most of the great discoveries of the 19th and 20th centuries were made before the appearance of state sponsorship, when the scientific enterprise was a fraction of its present size. Were the scientists who made these discoveries brighter than today's? That seems unlikely. A far more reasonable explanation is that fundamental science has already entered a period of diminished returns. "Look, don't get me wrong," says Mr. Horgan. "There are lots of important things still to study, and applied science and engineering can go on for ever. I hope we get a cure for cancer, and for mental disease, though there are few real signs of progress."
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单选题Which of the following can be the best title for the comment?______.
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单选题We all know that the normal human daily cycle of activity is of some 7-8 hours' sleep alternating with some 16-17 hours' wakefulness and that, broadly s peaking, the sleep normally coincides with the hours of darkness. Our present concern is with how easily and to what extent this cycle can he modified. The question is no mere academic one. The ease, for example, with which people can change from working in the day to winking at night is a question of growing importance in industry where automation calls for round-the-clock working of machines. It normally takes from five days to one week for a person to adapt to a reversed routine of sleep end wakefulness, sleeping during the day end working at night. Unfortunately, it is often the case in industry that shifts are changed every week; a person may work from 12 midnight to 8 a.m. one week, 8 a.m. to 4 p.m. the next, and 4 p. m. to 12 midnight the third and so on. This means that no sooner bas he got used to one routine than he has to change to another, so that much of his time is spent neither working nor sleeping very efficiently. The only real solution appears to be to hand over the night shift to a number of permanent night workers. An interesting study of the domestic life and health of night-shift workers was carried out by Brown in 1957. She found a high incidence of disturbed sleep and other disorders among those on alternating day and night shifts, but no abnormal occurrence of these phenomena among those on permanent night work. This latter system then appears to be the best long-term policy, but meanwhile something may be done to relieve the strains of alternate day and night work by selecting those people who can adapt most quickly to the changes of routine. One way of' knowing when a person has adapted is by measuring his body temperature. People engaged in normal daytime work will have a high temperature during the hours of wakefulness and a low one at night; when they change to night work the pattern will only gradually go back to match the new routine and the speed with which it does so parallels, broadly speaking, the adaptation of the body as a whole, particularly in terms of performance. There from, by taking body temperature at intervals of two hours throughout the period of wakefulness it can be seen how quickly a person can adapt to a reversed routine, and this could be used as a basis for selection. So far, however, such a form of selection does not seem to have been applied in practice.
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单选题Experts say walking is one of the best ways for a person to remain healthy.
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单选题Printmaking is the generic term for a number of processes, of which woodcut and engraving are two prime examples. Prints are made by pressing a sheet of paper (or other material) against an image-bearing surface to which ink has been applied. When the paper is removed, the image adheres to it, but in reverse. The woodcut had been used in China from the fifth century A.D. for applying patterns to textiles. The process was not introduced into Europe until the fourteenth century, first for textile decoration and then for printing on paper. Woodcuts are created by a relief process; first, the artist takes a block of wood, which has been sawed parallel to the grain, covers it with a white ground, and then draws the image in ink. The background is carved away, leaving the design area slightly raised. The woodblock is inked, and the ink adheres to the raised image. It is then transferred to damp paper either by hand or with a printing press. Engraving, which grew out of the goldsmith"s art, originated in Germany and northern Italy in the middle of the fifteenth century. It is an intaglio process (from Italian intagliare, "to carve"). The image is incised into a highly polished metal plate, usually copper, with a cutting instrument, or burin. The artist inks the plate and wipes it clean so that some ink remains in the incised grooves. An impression is made on damp paper in a printing press, with sufficient pressure-being applied so that the paper picks up the ink. Both woodcut and engraving have distinctive characteristics. Engraving lends itself to subtle modeling and shading through the use of fine lines. Hatching and cross-hatching determine the degree of light and shade in a print. Woodcuts tend to be more linear, with sharper contrasts between light and dark. Printmaking is well suited to the production of multiple images. A set of multiples is called an edition. Both methods can yield several hundred good-quality prints before the original block or plate begins to show signs of wear. Mass production of prints in the sixteenth century made images available, at a lower cost, to a much broader public than before.
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单选题We have seen life-saying medical devices ______ the market by the crushing costs of litigation.
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单选题Everyone who heard the story found it incredible.
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单选题Death comes quickly in the mountains. Each winter holiday makers are caught unawares as they happily ski away from the fixed runs, little realizing that a small avalanche can send them crashing in a bone-breaking fall down the slope and leave them buried under tons of crisp white snow. There are lots of theories about how to avoid disaster when hit by an avalanche. Practice is normally less cheerful. The snow in the Salzburg of Austria where a recent disaster took place was typical avalanche material: For several days before the incident I had skied locally. Early winter snow was wearing thin and covered with ice. On top of that new, warmer flakes were gently falling to produce a dangerous carpet. To the skier who enjoys unmarked slopes it is tempting stuff, deep new power snow on a hard base--the skiing that dreams are made of And sometimes nightmares. Snow falls in sections like a cake. Different sections have different densities because of the temperatures at the time of the fall and in the weeks afterwards. Problems come when any particular section is too thick and not sticking to the section beneath. The snow of the past few weeks had been falling in rather higher temperatures than those of December and early January. The result of these conditions is that even a slight increase in the temperatures sends a thin stream of water between the new snow and the old. Then the new snow simply slides off the mountain. Such slides are not unexpected. Local citizens know the slopes which tend to avalanche and the weather in which such slides are likely. Traps are set to catch the snow or prevent it slipping; bombs are placed and exploded from time to time to set off small avalanches before a big one has time to build up; and above all, skiers are warned not to ski in danger areas. In spite of this, avalanches happen in unexpected areas and, of course, skiers ignore the warnings. The one comfort to recreational skiers, however, is that avalanche incidents on the marked ski slopes are quite rare. No ski resort wants the image of being a death trap.
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单选题My own inclination , if I were in your situation, would be to look for another position.
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单选题It can be inferred from the third paragraph that ______.
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单选题"I have great confidence that by the end of the decade we"ll know in vast detail how cancer cells arise," says microbiologist Robert Weinberg, an expert on cancer. "But," he cautions, "some people have the idea that once one understands the causes, the cure will rapidly follow. Consider Pasteur, he discovered the causes of many kinds of infections, but it was fifty or sixty years before cures were available." This year, 50 percent of the 910,000 people who suffer from cancer will survive at least five years. In the year 2000, the National Cancer Institute estimates, that figure will be 75 percent. For some skin cancers, the five-year survival rate is as high as 90 percent. But other survival statistics are still discouraging—13 percent for lung cancer, and 2 percent for cancer of the pancreas. With as many as 120 varieties in existence, discovering how cancer works is not easy. The researchers made great progress in the early 1970s, when they discovered that oncogenes, which are cancer-causing genes, are inactive in normal cells. Anything from cosmic rays to radiation to diet may activate a dormant oncogene, but how remains unknown. If several oncogenes are driven into action, the cell, unable to turn them off, becomes cancerous. The exact mechanisms involved are still mysterious, but the likelihood that many cancers are initiated at the level of genes suggests that we will never prevent all cancers. "Changes are a normal part of the evolutionary process," says oncologist William Hayward. Environmental factors can never be totally eliminated; as Hayward points out, "We can"t prepare a medicine against cosmic rays." The prospects for cure, though still distant, are brighter. "First, we need to understand how the normal cell controls itself. Second, we have to determine whether there are a limited number of genes in cells which are always responsible for at least part of the trouble. If we can understand how cancer works, we can counteract its action."
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