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The idea has reigned for years that the aging brain’s neurons die off by as many as 100,000 a day—taking with them life’s cherished memories. But, in fact neuron-biologists such as Alan Peters of Boston University have shown in recent studies that, while brain cells may shrink in old age, they don’t die off in large numbers.What’s more, say neuroscientists, it’s primarily the brain’s “hardware”—the billions of telephone-line-like connections and relay switches which act as processing equipment—that is vulnerable to wearing out with age. The brain’s “software”—the actual information that fills up the mind over a lifetime—doesn’t necessarily deteriorate. If anything, it can grow more sophisticated. So, just as running the latest software program on an old computer will take more time and may involve some trouble, one car still possess a first-rate intelligence while losing some cognitive speed later in life.When mental abilities do pass their peak, memory isn’t the first to go, Powell and others say. It’s usually the brain’s capacity to make sense of spatial relationships—map-reading or finding your car at the mall—which may begin to get difficult in your 40s.A decade later, the abstract reasoning required to make analogies dips downward. Next to drop is “verbal memory after delay”—remembering details of a story after having turned attention to other tasks. But some mental skills, such as the ability to concentrate or calculate math, seem to remain sturdy long into old age. And “procedural” memory—how to play golf or ride a bike—is usually not touched by aging.Even “common” memory loss, however, shouldn’t be considered normal. It could be treatable. Neurologists at Harvard are finding that, later in life, the brain often produces less acetylcholine (乙酰胆碱), a neurotransmitter involved in memory. Tentative results suggest that drugs could mimic the missing chemical. At least a dozen other substances are also being studied as potential memory boosters.1. According to the passage, when we are old ________.2. According to the neuroscientists, the information in our mind ________.3. The neuroscientists compare our brain with computer to show that ________.4. According to the passage, at what age do our brains work best?5. What might happen when we are in our 50s?6. Which of the following is the best title of this passage?

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Nuclear power supplies 5% of the world’s energy from more than 400 plants. But with the exception of France and Japan, the rich world has stopped ordering new reactors. A technology that was once deemed both clean and “too cheap to meter” has proved to the neither. The industry’s chief hope now rests on the poor world. Western firms with reactors to sell will be flocking to Tokyo on October 8th for the World Energy Congress, a giant conference for the energy business. Asia, where electricity demand from developing countries is growing at 8% a year, will be on everyone’s lips. New reactors are planned in China, Taiwan, Indonesia, South Korea, Pakistan and India. It is good news for the reactor vendors; but these countries are making a mistake.The economic arguments for building new nuclear plants are flawed. The marginal costs of generating electricity from nuclear may be tiny, but as the technology now stands, huge and uncertain costs are involved in building the power stations, dealing with spent fuel, and decommissioning. Many western governments which sang nuclei’s praises now admit that gas and hydro power can produce cheaper electricity.The economics of nuclear power in the poor world could prove to the worse still. As in the rich world, fossil fuels such as gas and coal are invariably cheaper. In China the case for nuclear power may be a little stronger as domestic reserves of coal—though huge—are located far from some areas of growing electricity demand. But most developing countries are strapped for cash and need to increase electricity supply quickly to meet soaring demand. Nuclear plants fail on both counts: they are hugely capital-intensive, and can take as long as ten years to build.Those still charmed by nuclear power nowadays make three new arguments in its favor: that it is a defense against climate change, against another OPEC-administered oil shock, and against the inevitable exhaustion of fossil fuels. None bears close examination.1. Nuclear power has proved to be ________.2. Nuclear reactors ________.3. The author seems to suggest that ________.4. According to the article, which of the following statements is true?5. Building nuclear plants may involve all of the following EXCEPT ________.6. The advantages noted by those for nuclear power ________.

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Some accept their fate. Others try to reason with the police officer who has pulled them over for some real or imagined traffic offense. But when law enforcement is represented by a computer-driven camera that has immortalized your violation on film—as is the case at hundreds of intersections in more than 100 cities around the U.S.—it’s hard to talk your way out of a heavy fine. Yet that is precisely what some 300 motorists in San Diego succeeded in doing last week when a superior court judge rules that pictures taken by the so-called red-light cameras were unreliable and therefore unacceptable.The first U.S. Court decision to reject all the traffic violations caught on cameras; the ruling by Judge Ronald Styn has fueled debate over the growing use of the devices. Police departments swear, and studies indicate, that the robot cameras deter people from speeding and running red lights. A Lou Harris poll set for release this week finds that 69% of Americans support their use. Yet at least seven states have blocked proposals to implement them, and opponents—ranging from House majority leader Dick Armey to the American Civil Liberties Union—argue that the cameras violate privacy and place profit above public safety.Part of the problem is that virtually all the devices in place are operated by private firms that handle everything from installing the machinery to identifying violations—often with minimal police oversight—and have an incentive to pull in as many drivers as they can. The companies get paid as much as $70 a ticket, and the total revenue is hardly chump change. San Diego has got in $15.9 million last year and Washington $12.8 million. “It’s all about money,” says Congressman Bob Barr, a leading critic. Not so, insists Terrance Gainer, Washington’s executive assistant chief of police. “We have reduced fatalities. If some company is making money off that that is American way.”Critics counter that there must be other, less intrusive ways to make intersections safer, such as lengthening the yellow light and adding turn lanes. “I object to this fixation we have with cameras and electronically gathered information,” says Ban. “It places too much confidence in technology.” That confidence, as Washington residents have learned, can be misplaced. The city removed one camera last May that had generated more than 19,000 tickets at a particularly confusing intersection. In San Diego, faulty sensors made drivers appear to be going faster than they really were. The city suspended the system in July.Another concern is privacy. While systems in Washington, Maryland and North Carolina photograph nothing but the rear of the car, others in Arizona, California and Colorado take a picture of the driver’s seat as well—a bit of electronic monitoring that could land straying spouses in trouble a lot more serious than a traffic violation.In Europe, where robot cameras are deployed by the thousands and are even less popular than they are here, resentful drivers have started to take matters into their own hands, seeking out hidden cameras and knocking them over with their cars.1. It is mainly indicated in the first paragraph that ________.2. The court decision last week ________.3. Opponents’ arguments against cameras include all the following EXCEPT ________.4. Police department believes that ________.5. The phrase “chump change” in the third paragraph is closest in meaning to ________.6. According to the passage, Bob Barr ________.7. The writer’s attitude towards robot cameras can be best expressed as ________.8. Some drivers in European countries ________.

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Is life today more dangerous than it used to be? It certainly seems that way. Last week the entire Metro system in Washington had to close down because someone might be blown onto the tracks during a hurricane. This week children in Washington were not allowed to go to school for a whole day because streets were blocked by fallen trees and power lines, and traffic lights at some intersections weren’t working. A previous generation might have walked around the fallen trees and looked both ways before crossing the street, but the children of this generation clearly live in a much more dangerous world, and we need to protect them.After some serious air crashes, thousands of people in this country swore off airplanes and began driving cars. In fact, the number of deaths on U.S. highways in a typical year is more than double the number of people who have died in all commercial airplane accidents in the past 40 years. By taking the precaution of not flying, many people died.There are some clear psychological explanations for some of this. It is a fact, for example, that people fear man-made disasters (terrorism) far more than they fear natural disasters (hurricanes, snowstorms), even when the latter are more dangerous. Equally illogical, people are also more afraid of things they do not control, which is why driving a car does feel safer than flying in an airplane. Finally—although I have no proof—people are disproportionately frightened by things they read about in the newspaper. By contrast, they are disproportionately willing to discount the evidence of their own experience. If you look around your neighborhood, you’ll notice that the water is clean—which it wouldn’t necessarily have been 100 years ago—and that the food isn’t rotten or stale. Most children aren’t dying young. Most adults aren’t dying in middle age.Life is far safer and lasts much longer for the average American than it ever has for just about anybody at any other time in human history. But now that we’ve eliminated most of the things that the human race once feared, we’ve just invented new ones to replace them.1. Children in Washington are not allowed to go to school for the following reasons EXCEPT ________.2. It can be learned from the passage that the previous generation ________.3. It is indicated in the passage that in the past ________.4. The author believes that ________.5. The tone of the author in writing the passage is ________.

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What happens if people do not take into account the culture of the countries they are dealing with? Here are some examples.Mr. Byrd was hired by a well-known American corporation to be its “man in Riyadh”, Saudi Arabia. He went to the home of a Saudi, Mr. Fouad, to try to interest him in participating in a local joint venture with his company. As this was a first meeting, the men’s conversation began with “How are you doing? How’s your family? And how is your father?” that made Mr. Byrd a little impatient. Mr. Byrd, familiar with these obligatory formalities of greeting, answered “Fine, my father, yes, well, he is fine. I saw him a few months ago during Christmas when we took him out of the nursing home for a few days.”From that point everything froze up. Mr. Byrd’s mission was completely derailed because while Mr. Fouad remained gracious enough, he was obviously uninterested in doing any business with Mr. Byrd.The American was at a loss and didn’t know what he’d done wrong. In fact the problem with him is that he did not understand the family culture in this part of the world. It would have been inconceivable for the Saudi to have placed his father in the care of strangers. Mr. Fouad thus felt that he could not trust Mr. Byrd as a business partner.Another example, Jim Turner was attending a conference in Lyon. This was not his first trip to France, and he was pleased some of the French colleagues he’d met previously remembered him. One evening they invited him along for dinner. Shortly after the food was served, they began joking about the quality of the food. That surprised him. He thought the food was really rather good and said so, expecting the discussion to continue. But to his great discomfort, they then made some joke about “food and Americans” and changed the subject. He felt somewhat excluded and didn’t know what he’d done wrong.Interpretation: The French take great pride in their food and wine and foreigners should be very prudent about passing judgment on the quality of the food. In this case, the Frenchmen obviously thought that the food at the restaurant did not warrant such praise, and in their view, the American revealed his lack of taste.1. Mr. Byrd tried to persuade Mr. Fouad to ________.2. The conversation between Mr. Byrd and Mr. Fouad ________.3. Mr. Byrd’s problem lies in that he ________.4. Jim Turner praised the food because ________.5. We can conclude from the passage that when doing business abroad ________.

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