单选题Under pressure from animal welfare groups, two national science teachers associations have adopted guidelines that ban classroom experiments harming animals. The National Association of Biology Teachers and the National Science Teachers Association hope to end animal abuse in elementary and secondary schools and, in turn, discourage students from mishandling animals in home experiments and science fair projects. Animal welfare groups are apparently most concerned with high school students experimenting with animals in extracurricular projects. Barbara Orlans, President of the Scientists' Center for Animal Welfare, said that students have been performing surgery at random, testing known poisonous substances, and running other pathology experiments on animals without even knowing normal physiology. At one science fair, a student cut off the leg and tail of a lizard to demonstrate that only the tail can regenerate, she said. In another case, a student bound sparrows, starved them and observed their behavior. "The amount of abuse has been quite horrifying," Orlans said. Administrators of major science fairs are short-tempered over the teachers' policy change and the impression it has created. '"The teachers were sold a bill of goods by Barbara Orlans," said Thurman Grafton, who heads the rules committee for the International Science and Engineering Fair. "Backyard tabletop surgery is just nonsense. The new policies throw cold water on students' inquisitiveness," he said. Grafton said he wouldn't deny that there hasn't been animal abuse among projects at the international fair, but he added that judges reject contestants who have unnecessarily injured animals. The judges have a hard time monitoring local and regional fairs that may or may not choose to comply with the international fair's rules that stress proper care of animals, Grafton said. He said that several years ago, the Westinghouse Science Talent Search banned harmful experiments to animals when sponsors threatened to cancel their support after animal welfare groups lobbied for change. The teachers adopted the new policies also to fend off proposed legislation--in states including Missouri and New York that would restrict or prohibit experiments on animals. Officials of the two teachers organizations say that they don't know how many animals have been abused in the classroom. On the one hand, many biology teachers are not trained in the proper care of animals, said Wayne Moyer, executive director of the biology teachers' association. On the other, the use of animals in experiments has dropped in recent years because of school budget cuts. The association may set up seminars to teach better animal care to its members.

单选题If most participants end up with green shares, it means

单选题Under pressure from animal welfare groups, two national science teachers associations have adopted guidelines that ban classroom experiments harming animals. The National Association of Biology Teachers and the National Science Teachers Association hope to end animal abuse in elementary and secondary schools and, in turn, discourage students from mishandling animals in home experiments and science fair projects. Animal welfare groups are apparently most concerned with high school students experimenting with animals in extracurricular projects. Barbara Orlans, President of the Scientists' Center for Animal Welfare, said that students have been performing surgery at random, testing known poisonous substances, and running other pathology experiments on animals without even knowing normal physiology. At one science fair, a student cut off the leg and tail of a lizard to demonstrate that only the tail can regenerate, she said. In another case, a student bound sparrows, starved them and observed their behavior. "The amount of abuse has been quite horrifying," Orlans said. Administrators of major science fairs are short-tempered over the teachers' policy change and the impression it has created. "The teachers were sold a bill of goods by Barbara Ortans," said Thurman Grafton, who heads the rules committee for the International Science and Engineering Fair. "Backyard tabletop surgery is just nonsense. The new policies throw cold water on students' inquisitiveness," he said. Grafton said he wouldn't deny that there hasn't been animal abuse among projects at the international fair, but he added that judges reject contestants who have unnecessarily injured animals. The judges have a hard time monitoring local and regional fairs that may or may not choose to comply with the international fair's rules that stress proper care of animals, Grafton said. He said that several years ago, the Westinghouse Science Talent Search banned harmful experiments to animals when sponsors threatened to cancel their support after animal welfare groups lobbied for change. The teachers adopted the new policies also to fend off proposed legislation--in states including Missouri and New York--that would restrict or prohibit experiments on animals. Officials of the two teachers organizations say that they don't know how many animals have been abused in the classroom. On the one hand, many biology teachers are not trained in the proper care of animals, said Wayne Moyer, executive director of the biology teachers' association. On the other, the use of animals in experiments has dropped in recent years because of school budget cuts. The association may set up seminars to teach better animal care to its members. (414 words)Notes: pathology 病理学。lizard 蜥蜴。tabletop 桌面。short-tempered 脾气急躁的。lobby for 游说支持。fend off 躲开。

单选题The experiments led by Allan Rechtaschaffen and Bernard Bergmann at the University of Chicago ______.

单选题{{B}}Text 4{{/B}} The empty house, in a middle-class corner of southern California, is two storeys high and boasts a three-car garage. Roses bloom around a kidney-shaped swimming pool, which is green with algae. Bill Bobbitt, a county inspector, dips a ladle into the water and brings up half a dozen wriggling larvae. Mosquitoes, and the West Nile virus that some of them carry, are thriving in California's plunging property market. West Nile virus arrived in America in 1999 and made it to California three years later. Since then it is known to have infected 2,300 people in the state, of whom 76 have died. In Orange County this is the worst summer yet. By this point last year officials there had discovered nine birds that had been killed by West Nile virus and not one infected mosquito. So far this year they have found 219 infected birds and 75 infected mosquitoes. Some of this rise is due to better testing and co-operation with the animal services department, which receives most reports of dying birds. But a much bigger cause is the housing crunch. Fully 63,000 homes were foreclosed in California between April and June, according to DataQuick, a property data services outfit. In the past year the number of Orange County homeowners who have defaulted on their mortgages has more than doubled. Empty houses mean untended pools. Untended pools quickly breed mosquitoes. Dead birds are also piling up in neighbouring counties like Los Angeles, San Diego and San Bernardino, which also have high foreclosure rates. Last week 170 infected mosquitoes were discovered in the state as a whole-the highest tally ever. So far this year i3 human infections have been reported in California, but the numbers are expected to grow rapidly as the summer moves on. John Rusmisel, president-elect of the board responsible for killing the critters, says a peak in infected mosquitoes is generally followed, two or three weeks later, by a peak in human cases. In theory, owners are supposed to keep their properties in decent shape whether they live there or not. California has even passed a bill fining banks and mortgage companies that seize properties and then allow pools to fester. But Mr Bobbitt isn't waiting for the lawyers. He has treated the pool in Santa Ana with oil and synthetic growth hormones, which will keep the mosquitoes adolescent, preventing breeding. Then he tips in a few dozen mosquito fish (Gambusia affinis), which begin happily launching larvae. You can buy a lot of the fish for what a lawyer charges per hour, and some authorities, with commendable creativity, even provide them free to help control the pests.

单选题If good intentions and good ideas were all it took to save the deteriorating atmosphere, the planet's fragile layer of air would be as good as fixed. The two great dangers threatening the blanket of gases that nurtures and protects life on earth--global warming and the thinning ozone layer--have been identified. Better yet, scientists and policymakers have come up with effective though expensive countermeasures. But that doesn't mean these problems are anywhere close to being solved. The stratospheric ozone layer, for example, is still getting thinner, despite the 1987 international agreement known as the Montreal Protocol, which calls for a phaseout of chlorofluorocarbons (CFCs) and other ozone-depleting chemicals by the year 2006. CFCs--first fingered as dangerous in the 1970s by Sherwood Rowland and Mario Molina, two of this year's Nobel--prizewinning chemists—have been widely used for refrigeration and other purposes. If uncontrolled, the CFC assault on the ozone layer could increase the amount of hazardous solar ultraviolet light that reaches the earth's surface, which would, among other things, damage crops and cause cancer in humans. Thanks to a sense of urgency triggered by the 1985 detection of what has turned out to be an annual "hole" in the especially vulnerable ozone over Antarctica, the Montreal accords have spurred industry to replace CFCs with safer substances. Yet the CFCs already in the air are still doing their dirty work. The Antarctic ozone hole is more severe this year than ever before, and ozone levels over temperate regions are dipping as well. If the CFC phaseout proceeds on schedule, the atmosphere should start repairing itself by the year 2000, say scientists. Nonetheless, observes British Antarctic Survey meteorologist Jonathan Shanklin: "It will be the middle of the next century before things are back to where they were in the 1970s." Developing countries were given more time to comply with the Montreal Protocol and were promised that they would receive ＄ 250 million from richer nations to pay for the CFC phaseout. At the moment, though, only 60% of those funds has been forthcoming. Says Nelson Sabogal of the U. N. Environment Program: "If developed countries don't come up with the money, the ozone layer will not recuperate. This is a crucial time." It is also a critical time for warding off potentially catastrophic climate change. Waste gases such as carbon dioxide, methane and the same CFCs that wreck the ozone layer all tend to trap sunlight and warm the earth. The predicted results: an eventual melting of polar ice caps, rises in sea levels and shifts in climate patterns.

单选题The long year of food shortage in this country have suddenly given way to apparent abundance. Stores and shops are choked with food. Rationing (定量供应 ) is virtually suspended, and overseas suppliers have been asked to hold back deliveries. Yet, instead of joy, there is widespread uneasiness arid confusion. Why do food prices keep on rising, when there seems to be so much more food about? Is the abundance only temporary, or has it come to stay？Does it mean that we need to think less now about producing more food at home? No one knows what to expect. The recent growth of export-surpluses on the world food market has certainly been unexpectedly great, partly because a strange sequence of two successful grain harvests in North America is now being followed by a third. Most of Britain's overseas suppliers of meat, too, are offering more this and home production has also risen. But the effect of all this on the food situation in this country has been made worse by a simultaneous rise in food prices, due chiefly to the gradual cutting down of government support for food. The shops are overstocked with food not only because there is more food available, but also because people, frightened by high prices, are buying less of it. Moreover, the rise in domestic prices has come at a time when world prices have begun to fall, with the result that imported food, with the exception of grain, is often cheaper than the home -produced variety. And now grain prices, too are falling. Consumers are beginning to ask why they should not be enabled to benefit from this trend. The significance of these developments is not lost on farmers. The older generation have seen it all happen before. Despite the present price and market guarantees, farmers fear they are about to be squeezed between cheap food imports and a shrinking home market. Present production is running at 51 per cent above pre-war levels, and the government has called for an expansion to 60 per cent by 1956; but repeated ministerial advice is carrying little weight and the expansion program is not working very well.

单选题Large, multinational corporations may be the companies whose ups and downs seize headlines. But to a far greater extent than most Americans realize, the economy' s vitality depends on the fortunes of tiny shops and restaurants, neighborhood services and factories. Small businesses, defined as those with fewer than 100 workers, now employ nearly 60 percent of the work force and are expected to generate half of ail new jobs between now and the year 2000. Some 1.2 million small firms have opened their doors over the past six years of economic growth, and 1989 will see an additional 200,000 entrepreneurs striking off on their own. Too many of these pioneers, however, will blaze ahead unprepared. Idealists will overestimate the clamor for their products or fail to factor in the competition. Nearly everyone will underestimate, often fatally, the capital that success requires. Midcareer executives, forced by a takeover or a restructuring to quit the corporation and find another way to support themselves, may savor the idea of being their own boss but may forget that entrepreneurs must also, at least for a while, be bookkeeper and receptionist, too. According to Small Business Administration data,24 of every 100 businesses starting out today are likely to have disappeared in two years, and 27 more will have shut their doors four years from now. By 1995, more than 60 of those 100 start-ups will have folded. A new study of 3,000 small businesses, sponsored by American Express and the National Federation of Independent Business, suggests slightly better odds: Three years after start-up ,77 percent of the companies surveyed were still alive. Most credited their success in large part to having picked a business they already were comfortable in. Eighty percent had worked with the same product or service in their last jobs. Thinking through an enterprise before the launch is obviously critical. But many entrepreneurs forget that a firm' s health in its infancy may be little indication of how well it will age. You mast tenderly monitor its pulse. In their zeal to expand, small-business owners often ignore early warning signs of a stagnant market or of decaying profitability. They hopefully pour more and more money into the enterprise, preferring not to acknowledge eroding profit margins that mean the market for their ingenious service or product has evaporated, or that they must cut the payroll or vacate their lavish offices. Only when the financial well runs dry do they see the seriousness of the illness, and by then the patient is usually too far gone to save. Frequent checks of your firm's vital signs will also guide you to a sensible rate of growth. To snatch opportunity, you must spot the signals that it is time to conquer new markets, add products or perhaps franchise your hot idea.

单选题What would happen to the U. S. economy if all its commercial banks suddenly closed their doors? Throughout most of American history, the answer would have been a disaster of epic proportions, akin to the Depression wrought by the chain-reaction bank failures in the early 1930s. But in 1993 the startling answer is that a shutdown by banks might be far from cataclysmic. Consider this: though the economic recovery is now 27 months old, not a single net new dollar has been lent to business by banks in all that time. Last week the Federal Reserve reported that the amount of loans the nation's largest banks have made to businesses fell an additional $ 2. 4 billion in the week ending June 9, to $ 274. 8 billion. Fearful that the scarcity of bank credit might sabotage the fragile economy, the White House and federal agencies are working feverishly to encourage banks to open their lending windows. In the past two weeks, government regulators have introduced steps to make it easier for banks to lend. Is the government's concern fully justified? Who really needs banks these days? Hardly anyone, it turns out. While banks once dominated business lending, today nearly 80% of all such loans come from nonbank lenders like life insurers, brokerage firms and finance companies. Banks used to be the only source of money in town. Now businesses and individuals can write checks on their insurance companies, get a loan from a pension fund, and deposit paychecks in a money-market account with a brokerage firm. "It is possible for banks to die and still have a vibrant economy," says Edward Furash, a Washington bank consultant. The irony is that the accelerating slide into irrelevance comes just as the banks racked up record profits of $ 43 billion over the past 15 months, creating the illusion that the industry is staging a comeback. But that income was not the result of smart lending decisions. Instead of earning money by financing America's recovery, the banks mainly invested their funds--on which they were paying a bargain-basement 2% or so--in risk-free Treasury bonds that yielded 7%. That left bank officers with little to do except put their feet on their desks and watch the interest roll in. Those profits may have come at a price. Not only did bankers lose many loyal customers by withholding credit, they also inadvertently opened the door to a herd of nonbank competitors, who stampeded into the lending market. "The banking industry didn't see this threat," says Furash. "They are being fat, dumb and happy. They didn't realize that banking is essential to a modern economy, but banks are not./

单选题According to those who support the liberalization of Europe's energy markets, energy supply monopoly is unlikely on the grounds that

单选题{{B}}Text 2{{/B}} Teach for America (TFA) was founded by Wendy Kopp in 1990. It is a non-profit organisation that recruits top-notch graduates from elite institutions and gets them to teach for two years in struggling state schools in poor areas. I had thought the programme was about getting more high-quality teachers — but that, it appears, is a secondary benefit. “This is about enlisting the energy of our country’s future leaders in its long-term educational needs, and eliminating inequity,” Wendy explains. It’s great if “corps members”, as TFA calls its active teachers, stay in the classroom — and many do, and rise quickly through the ranks. But the “alums”, as she calls those who have finished their two-year teaching, who don’t stay in schools often go on to lead in other fields, meaning that increasing numbers of influential people in all walks of life learn that it is possible to teach successfully in low-income communities, and just what it takes. “It means you realise that we can solve this problem.” As she continues to talk I realise that TFA is — in the best possible sense — a cult. It has its own language (“corps members”, “alums”), recruits are instilled (“We tell them that it can be done, that we know of hundreds, thousands, of teachers attaining tremendous success”), go through an ordeal (“Everyone hits the wall in week three in the classroom”), emerge transformed by privileged knowledge (“Once you know what we know — that kids in poor urban areas can excel — you can accomplish different things”) and can never leave (alumni form a growing, and influential, network). I have not seen the same zeal when talking to those on the equivalent programme in England, Teach First., in which the missionary-style language imported from America had to be toned down, because it just didn’t suit the restrained English style. But could that favour be necessary for its success? Chester, an alum, takes me to visit three TFA corps members at a middle school in the Bronx. They are impressive young people, and their zeal is evident. Two intend to stay in teaching; both want to open charter schools. One, a Hispanic woman, is working out with a friend how to educate migrant Hispanic labourers in Texas; the other would like to open a “green” charter, but in the meantime he has accepted a job with the KIPP charter group in Newark, New Jersey. All three are tired. Their classrooms are not much like the rest of the school where they work, and their heroic efforts are only supported by Chester and each other, not by their co-workers. “The first year was unbelievably bad,” one tells me. “So many years with low expectations meant a lot of resistance from the kids. Eventually they saw the power and the growth they were capable of.”

单选题The growth of cell-phone users declines because