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单选题In most parts of the world, climate change is a worrying subject. Not so in California. At a recent gathering of green luminaries—in a film star's house, naturally, for that is how seriousness is often established in Los Angeles—the dominant note was self-satisfaction at what the state has already achieved. And perhaps nobody is more complacent than Arnold Schwarzenegger. Unlike A1 Gore, a presidential candidate turned prophet of environmental doom, California's governor sounds cheerful when talking about climate change. As well he might: it has made his political career. Although California has long been an environmentally-conscious state, until recently greens were concerned above all with smog and redwood trees. "Coast of Dreams", Kevin Stag's authoritative history of contemporary California, published in 2004, does not mention climate change. In that year, though, the newly-elected Mr. Schwarzenegger made his first tentative call for western states to seek alternatives to fossil fuels. Gradually he noticed that his efforts to tackle climate change met with less resistance, and more acclaim, than just about all his other policies. These days it can seem as though he works on nothing else. Mr. Schwarzenegger's transformation from screen warrior to eco-warrior was completed last year when he signed a bill imposing legally-enforceable limits on greenhouse—gas emissions—a first for America. Thanks mostly to its lack of coal and heavy industry, California is a relatively clean state. If it were a country it would be the world's eighth-biggest economy, but only its 16th-biggest polluter. Its big problem is transport—meaning, mostly, cars and trucks, which account for more than 40% of its greenhouse-gas emissions compared with 32% in America as a whole. The state wants to ratchet down emissions limits on new vehicles, beginning in 2009. Mr. Schwarzenegger has also ordered that, by 2020, vehicle fuel must produce 10% less carbon: in the production as well as the burning, so a simple switch to corn-based ethanol is probably out. Thanks in part to California' s example, most of the western states have adopted climate action plans. When it comes to setting emission targets, the scene can resemble a posedown at a Mr. Olympia contest. Arizona's climate-change scholars decided to set a target of cutting the state's emissions to 2000 levels by 2020. But Janet Napolitano, the governor, was determined not to be out-muscled by California. She has declared that Arizona will try to return to 2000 emission levels by 2012. California has not just inspired other states; it has created a vanguard that ought to be able to prod the federal government into stronger national standards than it would otherwise consider. But California is finding it easier to export its policies than to put them into practice at home. In one way, California' s self-confidence is fully justified. It has done more than any other state—let alone the federal government—to fix America's attention on climate change. It has also made it seem as though the problem can be solved. Which is why failure would be such bad news. At the moment California is a beacon to other states. If it fails, it will become an excuse for inaction.
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单选题Every code of etiquette has contained three elements.
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单选题{{B}}Text 2{{/B}} SoBig. F was the more visible of the two recent waves of infection because it propagated itself by e-mail, meaning that victims noticed what was going on. SoBig. F was so effective that it caused substantial disruption even to those protected by anti-virus software. That was because so many copies of the virus spread (some 500,000 computers were infected) that many machines were overwhelmed by messages from their own anti-virus software. On top of that, one common counter-measure backfired, increasing traffic still further. Anti-virus software often bounces a warning back to the sender of an infected e-mail, saying that the e-mail in question cannot be delivered because it contains a virus. SoBig. F was able to spoof this system by "harvesting" e-mail addresses from the hard disks of infected computers. Some of these addresses were then sent infected e-mails that had been doctored to look as though they had come from other harvested addresses. The latter were thus sent warnings, even though their machines may not have been infected. Kevin Haley of Symantec, a firm that makes anti-virus software, thinks that one reason SoBig. F was so much more effective than other viruses that work this way is because it was better at searching hard drives for addresses. Brian King, of CERT, an internet-security centre at Carnegie-Mellon University in Pittsburgh, notes that, unlike its precursors, SoBig. F was capable of "multi-threading", it could send multiple e-mails simultaneously, allowing it to dispatch thousands in minutes. Blaster worked by creating a "buffer overrun in the remote procedure call". In English, that means it attacked a piece of software used by Microsoft's Windows operating system to allow one computer to control another. It did so by causing that software to use too much memory. Most worms work by exploiting weaknesses in an operating system, but whoever wrote Blaster had a particularly refined sense of humour, since the website under attack was the one from which users could obtain a program to fix the very weakness in Windows that the worm itself was exploiting. One Way to deal with a wicked worm like Blaster is to design a fairy godmother worm that goes around repairing vulnerable machines automatically. In the case of Blaster someone seems to have tried exactly that with a program called Welchi. However, according to Mr. Haley, Welchi has caused almost as many problems as Blaster itself, by overwhelming networks with "pings" signals that checked for the presence of other computers. Though both of these programs fell short of the apparent objectives of their authors, they still caused damage. For instance, they forced the shutdown of a number of computer networks, including the one used by the New York Times newsroom, and the one organising trains operated by CSX, a freight company on America's east coast. Computer scientists expect that it is only a matter of time before a truly devastating virus is unleashed.
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单选题Is the literary critic like the poet, responding creatively, intuitively, subjectively to the written word as the poet responds to human experience? Or is the critic more like a scientist, following a series of demonstrable, verifiable steps, using an objective method of analysis? For the woman who is a practitioner of feminist literary criticism, the subjectivity versus objectivity, or critic-as-artist-or-scientist, debate has special significance; for her, the question is not only academic, but political as well, and her definition will provoke special risks whichever side of the issue it favors. If she defines feminist criticism as objective and scientific--a valid, verifiable, intellectual method that anyone, whether man or woman, can perform--the definition not only makes the critic-as-artist approach impossible, but may also hinder accomplishment of the utilitarian political objectives of those who seek to change the academic establishment and its thinking, especially about sex roles. If she defines feminist criticism as creative and intuitive, privileged as art, then her work becomes vulnerable to the prejudices of stereotypic ideas about the ways in which women think, and will be dismissed by much of the academic establishment. Because of these prejudices, women who use an intuitive approach in their criticism may find themselves charged with inability to be analytical, to be objective, or to think critically. Whereas men may be free to claim the role of critic-as-artist, women run different professional risks when they choose intuition and private experience as critical method and defense. These questions are political in the sense that the debate over them will inevitably be less an exploration of abstract matters in a spirit of disinterested inquiry than an academic power struggle, in which the careers and professional fortunes of many women scholars only now entering the academic profession in substantial numbers will be at stake, and with them the chances for a distinctive contribution to humanistic understanding, a contribution that might be an important influence against sexism in our society. As long as the academic establishment continues to regard objective analysis as "masculine" and an intuitive approach as "feminine," the theoretician must steer a delicate philosophical course between the two. If she wishes to construct a theory of feminist criticism, she would be well advised to place it within the framework of a general theory of the critical process that is neither purely objective nor purely intuitive. Her theory is then more likely to be compared and contrasted with other theories of criticism with some degree of dispassionate distance. (418 words)
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单选题The author's attitude toward FCC's new rules seems to be
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单选题The Scottish countryside will soon be home to creatures which is strange to Britain. This spring, 17 beavers (海狸) will be released into a remote area of rivers and forests. Hunted to extinction throughout Europe, beavers haven"t roamed Britain"s wilderness for almost 500 years. Ecologists would like to invite back other long-lost species to help restore the natural balance. To save the country"s plants from deer, which have doubled to 2 million since the start of this decade, an Oxford University biologist late last year called for reintroducing the lynx (猞猁)—a wildcat that died out in Britain 1,300 years ago. Nature has long been a popular cause in Europe. British people love their countryside of fences and fields, the French their vineyards (葡萄园) and the Germans their hiking forests. But in recent years conservationists have set their sights on the more distant past, when Europe"s forests and meadows were full of elephants, hippo-potamuses (河马), rhinoceroses(犀牛) and big cats. Some ambitious conservationists are now advocating a return to norms of wilderness that date back to 11,000 years ago when the biggest mammals were at the top of the food chain. Nobody is advocating allowing elephants and lions to run crazily in this densely populated region. But wilding supporters would give free control to a long list of lesser mammals, including the beaver and the lynx, which some people fear could be destructive. Some landowners withdraw at the thought of beavers cutting down trees with their teeth and flooding their property; the Scottish Parliament rejected several earlier efforts to reintroduce the mammal. Proposals to set loose wolves and bears in Britain have also encountered resistance. Although rhinos and hippos thrived in Europe thousands of years ago, no one is sure what effect they would have on ecosystems now. "The idea of bringing back big mammals is interesting, but when you get down to the nuts and bolts, there"s a lot of questions," say some biologists. For example, elephants could destroy what little forest and grassland Europe has left. The beavers of Tierra del Fuego provide a cautionary tale. When a failed commercial fur farm released its few remaining beavers into the wild 60 years ago, the population exploded, and they are still revenging the local people. Is this Britain"s future? Supporters say no, the beaver will fit right in. Destroying nature is not a job for the mild.
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单选题The author, according to the text, seems to
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单选题Low levels of literacy and numeracy have a damaging impact on almost every aspect of adults, according to a survey published yesterday, which offers (1) of a developing underclass. Tests and (2) with hundreds of people born in a week in 1958 graphically illustrated the (3) of educational underachievement. The effects can be seen in unemployment, family (4) , low incomes, depression and social inactivity. Those who left school at 16 with poor basic skills had been employed for up to four years less than good readers (5) they reached 37. Professor John Bynner, of City University, who carried the research, said that today's (6) teenagers would even encounter greater problems because the supply of (7) jobs had shrunk. Almost one fifth of the 1,700 people interviewed for yesterday's report had poor literacy and almost half (8) with innumeracy, a proportion (9) other surveys for the Basic Skills Agency. Some could not read a child's book, and most found difficult (10) written instructions. Poor readers were twice as likely to be on a low wage and four times as likely to live in a household where partners worked. Women in this (11) were five times as likely to be (12) depressed, (13) both tended to feel they had no control over their lives, and to trust others (14) . Those who had low literacy and numeracy were seldom (15) in any community organization and less likely than others to (16) in a general election. There had been no (17) in the literary level of (18) reporting problems. Alan Wells, the agency's director, said: "The results emphasize the dangers of developing an underclass people, who were out of work, (19) depressed and often labeled themselves as (20) . There is a circle of marginalization, with the dice against these people and their families. /
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单选题We can learn from the last paragraph that the boost of DTV sales is NOT due to
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单选题For centuries in Spain and Latin America, heading home for lunch and a snooze with the family was some thing like a national right, but with global capitalism standardizing work hours, this idyllic habit is fast becoming an endangered pleasure. Ironically, all this is happening just as researchers are beginning to note the health benefits of the afternoon nap. According to a nationwide survey, less than 25 percent of Spaniards still enjoy siestas. And like Spain, much of Latin America has adopted Americanized work schedules, too, with shortened lunch times and more rigid work hours. Last year the Mexican government passed a law limiting lunch breaks to one hour and requiring its employees to work their eight-hour shift between 7 a.m. and 6 p.m.. Before the man-date, workers would break up the shift—going home midday for a long break with the family and returning to work until about 9 or 10 p.m.. The idea of siesta is changing in Greece, Italy and Portugal, too, as they rush to join their more "industrious" counterparts in the global market. Most Americans I know covet sleep, but the idea of taking a nap mid-afternoon equates with laziness, un employment and general sneakiness. Yet according to a National Sleep Survey poll, 65 percent of adults do not get enough sleep. Numerous scientific studies document the benefits of nap taking, including one 1997 study on the deleterious effects of sleep deprivation in the journal Internal Medicine . The researchers found that fatigue harms not only marital and social relations but worker productivity. According to Mark Rosekind, a former NASA scientist and founder of Solutions in Cupertino, Calif., which educates businesses about the advantages of sanctioning naps, we"re biologically programmed to get sleepy between 3 and 5 p.m. and 3 and 5 a.m.. Our internal timekeeper—called the circadian clock—operates on a 24-hour rotation and every 12 hours there"s a dip. In accordance with these natural sleep rhythms, Rosekind recommends that naps be either for 40 minutes or for two hours. Latin American countries, asserts Rosekind, have had it right all along. They"ve been in sync with their clocks; we haven" t. Since most of the world is sleep-deprived, getting well under the recommended eight hours a night (adults get an average of 6.5 hours nightly), we usually operate on a kind of idle midday. Naps are even more useful now that most of us forfeit sleep because of insane work schedules, longer commute times and stress, In a study published last April, Brazilian medical researchers noted that blood pressure and arterial blood pressure dropped during a siesta.
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单选题 Advertising is a form of selling. For thousands of years there have been individuals who have tried to {{U}}(1) {{/U}} others to buy the food they have produced or the goods they have made or the services they can {{U}}(2) {{/U}}. But in the 19th century the mass production of goods {{U}}(3) {{/U}} the Industrial Revolution made person-to-person selling inefficient. The mass distribution of goods that {{U}}(4) {{/U}} the development of the highway made person-to-person selling {{U}}(5) {{/U}} slow and expensive. At the same time, mass communication, first newspapers and magazines, {{U}}(6) {{/U}} radio and television, made mass selling through {{U}}(7) {{/U}} possible. The objective of any advertisement is to convince people that it is in their best {{U}}(8) {{/U}} to take the action the advertiser is recommending. The action {{U}}(9) {{/U}} be to purchase a product, use a service, vote for a political candidate, or {{U}}(10) {{/U}} to join the Army. Advertising as a {{U}}(11) {{/U}} developed first and most rapidly in the United States, the country that uses it to the greatest {{U}}(12) {{/U}}. In 1980 advertising expenditure in the U.S. exceeded 55 billion dollars, or {{U}}(13) {{/U}} 2 percent of the gross national product. Canada spent about 1.2 percent of its gross national product {{U}}(14) {{/U}} advertising. {{U}} (15) {{/U}} advertising brings the economies of mass selling to the manufacturer, it {{U}}(16) {{/U}} benefits for the consumer {{U}}(17) {{/U}}. Some of those economies are passed along to the purchaser so that the cost of a product sold primarily through advertising is usually far {{U}}(18) {{/U}} than one sold through personal salespeople. Advertising {{U}}(19) {{/U}} people immediate news about products that have just come on the market. Finally, advertising {{U}}(20) {{/U}} for the programs on commercial television and radio and for about two thirds of the cost of publishing magazines and newspapers.
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单选题 A meager diet may give you health and long life, but it's not much fun-and it might not even be necessary. We may be able to hang on to most of that youthful vigor even if we don't start to diet until old age. Stephen Spindler and his colleagues from the University of California at Riverside have found that some of an elderly mouse's liver genes can be made to behave as they did when the mouse was young simply by limiting its food for four weeks. The genetic rejuvenation won't reverse other damage caused by time for the mouse, but could help its liver metabolize drugs or get rid of toxins. Spindler's team fed three mice a normal diet for their whole lives, and fed another three on half-rations. Three more mice were switched from the normal diet to half-feed for a month when they were 34 months old-equivalent to about 70 human years. The researchers checked the activity of 11,000 genes from the mouse livers, and found that 46 changed with age in the normally fed mice. The changes were associated with things like inflammation and free radical production-probably bad news for mouse health. In the mice that had dieted all their lives, 27 of those 46 genes continued to behave like young genes. But the most surprising finding was that the mice that only started dieting in old age also benefited from 70 percent of these gene changes. "This is the first indication that these effects kick in pretty quickly," says Huber Warner from the National Institute on Aging near Washington, D.C. No one yet knows if calorie restriction works in people as it does in mice, but Spindler is hopeful. "There's attracting and tempting evidence out there that it will work," he says. If it does work in people, there might be good reasons for rejuvenating the liver. As we get older, our bodies are less efficient at metabolizing drugs, for example. A brief period of time of dieting, says Spindler, could be enough to make sure a drug is effective. But Spindler isn't sure the trade-off is worth it. "The mice get less disease, they live longer, but they're hungry," he says. "Even seeing what a diet does, it's still hard to go to a restaurant and say: 'I can only eat half of that'." Spindler hopes we soon won't need to diet at all. His company, Life Span Genetics in California, is looking for drugs that have the effects of calorie restriction.
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