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Questions 1 to 5 are based on the following conversation.
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Questions 1 to 5 are based on the following conversation.
Over the years, Allan Rechtschaffen has killed a lot of rats just by keeping them awake. In his sleep laboratory at the University of Chicago, Rechtschaffen places each rat on an enclosed turntable contraption that begins spinning whenever the rodent’s brain waves suggest it is beginning to nod off-forcing the rodent to keep moving so that it doesn’t bump into a wall. After about a week of enforced consciousness, the rat begins showing some signs of strain. Odd lesions break out on its tail and paws. It becomes irritable. Its body temperature drops even as it attempts to make itself warmer than usual. It eats twice as much food as normal but loses 10 to 15 percent of its body weight. After about 17 days of sleeplessness, the rat dies. What kills it "We don’t know," says Rechtschaffen. Thus it goes in the science of sleep. Rats can last about 16 days without eating, suggesting that sleep is nearly as vital to life as is food. Yet scientists are far from answering the seemingly simple question of what, exactly, sleep is good for. Of course, there’s no shortage of hypotheses; insomniacs hoping for some shut-eye might do well to count sleep theories instead of sheep. Many of the most popular theories are extensions of common-sense propositions from human experience. Since we feel rested after sleep, some researchers argue-that sleep must be for rest. Harold Zepelin, professor emeritus in psychology at Michigan’s Oakland University, regards sleep as a period of mandatory energy conservation. "We can’t afford to be active 24 hours per day," syas Zepelin, so evolution dictated this daily period of hibernation. (Some even argue that one reason sleep evolved in humans was to keep us unconscious and out of harm’s way during the night, when we are not exactly the king of beasts.) Smaller animals such as rodents, which have high metabolisms and expend proportionately more energy to make up for the rapid loss of heat that is a geometric consequence of smallness, do tend to sleep more. Larger animals such as giraffes sleep less than five hours each day. But the energy savings from sleep in large animals are so small it is hard to see why they would sleep at all by this theory. Humans save merely 120 kilocalories a night (about the equivalent of an apple) by sleeping rather than staying awake. Moreover, even hibernating animals arouse themselves from torpor to enter sleep and then fall back into hibernation, suggesting that there is a deeper need for sleep than a mere recharging of the body’s batteries. Dennis McGinty believes part of the function of sleep is to cool off the brain. The chief of neurophysiology research at Los Angeles’s Sepulveda Veterans Hospital, McQmty points to a feedback loop in the brain that seems to trigger sleep when the brain gets too hot. When provided with a bar to increase cage temperature, rats that are kept awake jack up the heat about 10 degrees Celsius. By attempting to get warmer than usual, the rats may be hoping to trigger sleep-inducing neurons. The phenomenon also occurs in humans. "If you exercise in the extreme heat, it practically knocks you out," McGinty notes. Well-trained athletes who are able to increase their body temperature during exercise—unlike us weekend workout warriors—sleep about one hour longer than normal. In essence, a jump in body temperature activates heat-sensitive neurons to slow down the body’s metabolism—preferably by sleep—and thus cool down the brain. The body’s minimum temperature comes during the deepest sleep, typically at around 5 a.m. From the passage, we can infer the reason why Allan Rechtschaffen has killed a lot of rats just by keeping them awake is that he wants to______.
患者，男，20岁，因反复喷嚏、流涕、鼻痒4年，复发1周就诊，春季多发，流清水涕，喷嚏一次最多10个，服用感冒药症状有缓解，既往有湿疹病史。体检：T36．6℃，咽无充血，双侧下鼻甲肥大，黏膜苍白，鼻腔清水样分泌物，双肺呼吸音清，无干湿啰音。需要进行哪些检查明确诊断
Most big corporations were once run by individual capitalists: by one shareholder with enough stock to dominate the board of directors and to dictate policy, a shareholder who was usually also the chief executive officer. Owning a majority or controlling interest, these capitalists did not have to concentrate on reshuffling assets to fight off raids from financial vikings. They were free to make a living by producing new products or by producing old products more cheaply. Just as important, they were locked into their roles. They could not very well sell out for a quick profit—dumping large stock holdings on the market would have simply depressed the stock’s price and cost them their jobs as captains of industry. So instead they sought to enhance their personal wealth by investing—by improving the long-run efficiency and productivity of the company. Today, with very few exceptions, the stock of large U. S. corporations is held by financial institutions such as pension funds, foundations, or mutual funds—not by individual shareholders. And these financial institutions cannot legally become real capitalists who control what they own. How much they can invest in any one company is limited by law, as is how actively they can intervene in company decision making. These shareholders and corporate managers have a very different agenda than dominant capitalists do, and therein lies the problem. They do not have the clout to change business decisions, corporate strategy, or incumbent managers with their voting power. They can enhance their wealth only by buying and selling shares based on what they think is going to happen to short-term profits. Minority shareholders have no choice but to be short-term traders. And since shareholders are by necessity interested only in short-term trading, it is not surprising that managers’ compensation is based not on long-term performance, but on current profits or sales. Managerial compensation packages are completely congruent with the short-run perspective of short run shareholders. Neither the manager nor the shareholder expects to be around very long. And neither has an incentive to watch out for the long term growth of the company. We need to give managers and shareholders an incentive to nurture long-term corporate growth—in other words, to work as hard at enhancing productivity and output as they now work at improving short-term profitability. Most shareholders and corporate managers become wealthy______.
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