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听力原文：M: Suppose I forgot either the title or the author but simply want to look at some books on suspension bridges？ What shall I do？
W: In this case you can look under "bridge". The information on the card will help you.
Q: Where do you suppose the above conversation takes place？
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Polluted water is nothing new in the United States. We have lived through flaming rivers and caustic creaks that could take the hide off a hound. For decades, however, efforts to safeguard drinking water were hampered because no one had an accurate sense of the full range of contaminants in the water supply, nor of the geographic extent of the pollution. This year two separate research teams unveiled sophisticated new tools to find out exactly what chemical dangers are lurking in freshwater streams.
"Research in Europe in the 1990s showed that pharmaceuticals were turning up in the water," says Dana Kolpin, leader of a U. S. Geological Survey Water Resources Division research ream that developed five new analytic methods for measuring water contaminants." Our big effort was to develop methods to measure very small amounts of organic chemicals. ' The research team fanned out across 30 states nationwide and conducted two years of sampling from 139 streams. They were chosen, says Kolpin, on the basis of their location downstream from" intense urbanization and livestock production." In a study published in the March 15 Journal of Environmental Science & Technology, Kolpin and his colleagues reported they looked for 95 different contaminants, such as antibiotics, steroids, hormones, antioxidants, plasticizers, and various solvents. They found 82 of them. Nearly 80 percent of the streams showed one or more of the contaminants. The median stream contained seven. Even the good news--that the most frequently detected contaminants like fecal steroids, cholesterol, insect repellent, caffeine, disinfectant, fire retardant, and detergents were found in generally low concentrations--had to be qualified. Many of those compounds have no guidelines for safe amounts, and little is known about the effects of chronic exposure or the interactive effects of compounds that have been detected together.
In a related Environmental Protection Agency study that is still in progress, a team of scientists at the Johns Hopkins Whiting School of Engineering is using gas chromatography and mass spectrometry to detect the presence of various anticonvulsants and anticancer drugs in drinking water. Led by Lynn Roberts and Ed Bouwer, the researchers track samples at sewage-treatment facilities in Massachusetts and Maryland to determine whether and in what quantities pharmaceuticals are getting through the waste-treatment plants and the extent to which they may be accumulating in coastal waters.
The goal of both research teams is to provide a baseline of what organic compounds are in the water, in what quantities, and how they are getting there--key steps toward ensuring that the water we drink isn't killing us.
The second sentence of the first paragraph, "We have lived through..., off a hound", intends to say that ______.
听力原文： People born in the autumn live longer than those born in the spring and are less likely to fall chronically ill when they are older, according to an Austrian scientist.
Using census data for more than one million people in Austria, Denmark and Australia, scientists at the Max Planck Institute for Demographic Research in the northern German town of Rostock found the month of birth was related to life expectancy over the age of 50. Seasonal differences in what mothers ate during pregnancy, and infections occurring at different times of the year could both have an impact on the health of a new-born baby and could influence its life expectancy in older age.
"A mother giving birth in spring spends the last phase of her pregnancy in winter, when she will eat less vitamins than in summer, ' said Gabriele Doblhammer, one of a team of scientists who carried out the research. "When she stops breast-feeding and starts giving her baby normal food, it's in the hot weeks of summer when babies are prone to infections of the digestive system. '
In Austria, adults born in autumn (October-December) lived about seven months longer than those born in spring (April-June), and in Denmark adults with birthdays in autumn outlived those born in spring by about four months. In the southern hemisphere, the picture was similar. Adults born in the Australian autumn—the European spring—lived about four months longer than those born in the Australian spring. The study focused on people born at the beginning of the 20th century, using death certificates and census data. Although nutrition at all times of the year has improved since then, the seasonal pattern persists, Doblhammer said.
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A．He was criticized hy the teacher because he was late.B．He couldn't answer the questi
The movies that want to race for Academy Award nomination should be seen by all the members of the Academy.
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