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Every living thing has an inner biological clock that controls behavior. The clock works all the time even when there are no outside signs to mark the passing of time. The biological clock tells plants when to form flowers and when the flowers should open. It tells insects when to leave the protective cocoon and fly away. And it tells animals when to eat, sleep and wake. It controls body temperature, the release of some hormones and even dreams. These natural daily events are circadian rhythms. Man has known about them for thousands of years. But the first scientific observation of circadian rhythms was not made until 1729. In that year French astronomer, Jean-Jacques d’Ortous de Mairan, noted that one of his plants opened its leaves at the same time every morning, and closed them at the same time every night. The plant did this even when he kept it in a dark place all the time. Later scientists wondered about circadian rhythms in humans. They learned that man’s biological clock actually keeps time with a day of a little less than 25 hours instead of the 24 hours on a man-made clock. About four years ago an American doctor, Eliot Weitzman, established a laboratory to study how our biological clock works. The people in his experiments are shut off from the outside world. They are free to listen to and live by their circadian rhythms. Dr. Weitzman hopes his research will lead to effective treatments for common sleep problems and sleep disorders caused by aging and mental illness. The laboratory is in the Monteflore Hospital in New York City. It has two living areas with three small rooms in each. The windows are covered, so no sunlight or moonlight comes in. There are no radios or television receivers. There is a control room between the living areas. It contains computers, one-way cameras and other electronic devices for observing the person in the living area. The instruments measure heartbeat, body temperature, hormones in the blood, other substances in the urine and brain waves during sleep. A doctor or medical technician is on duty in the control room 24 hours a day during an experiment They do not work the same time each day and are not permitted to wear watches, so the person in the laboratory has no idea what time it is. In the first four years of research, Dr Weitzman and his assistant have observed 16 men between the ages of 21 and 80. The men remained in the laboratory for as long as six months. Last month, a science reporter for The New York Times newspaper, Dava Sobol, became the first woman to take part in the experiment. She entered the laboratory on June 13th and stayed for 25 days. Miss Sobol wrote reports about the experiment during that time, which were published in the newspaper. The sentence "They are free to listen to and live by their circadian rhythms." (In Paragraph 4) probably means ______.
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There are hidden factors which scientists call "feedback mechanisms". No one knows quite how they will interact with the changing climate. Here’s one example: plants and animals adapt to climate change over centuries. At the current estimate of half a degree centigrade of warming per decade, vegetation may not keep up. Climatologist James Hansen predicts climate zones will shift toward the poles by 50 to 75 kilometers a year--faster than trees can naturally migrate. Species that find themselves in an unfamiliar environment will die. The 1000-kilometer-wide strip of forest running through Canada, Russia, and Scandinavia could be cut by half. Millions of dying trees would soon lead to massive forest fires, releasing tons of CO2 and further boosting global warming. There are dozens of other possible "feedback mechanisms". Higher temperatures will fuel condensation and increase cloudiness, which may actually damp down global warming. Others, like the "albedo" effect is the amount of solar energy reflected by the earth’s surface. As northern ice and snow melts and the darker sea and land pokes through, more heat will be absorbed, adding to the global temperature increase. Even if we were to magically stop all greenhouse-gas emissions tomorrow the impact on global climate would continue for decades. Delay will simply make the problem worse. The fact is that some of us are doing quite well the way things are. In the developed world prosperity has been built on 150 years of cheap fossil fuels. Material progress has been linked to energy consumption. Today 75 percent of all the world’s energy is consumed by a quarter of the world’s population. The average rich-world resident adds about 3.2 tons of CO2 yearly to the atmosphere, more than four times the level added by each Third World citizen. The US, with just seven percent of the global population, is responsible for 22 percent of global warming. The word "emission" in paragraph 3 is closest in meaning to ______.
There are hidden factors which scientists call "feedback mechanisms". No one knows quite how they will interact with the changing climate. Here’s one example: plants and animals adapt to climate change over centuries. At the current estimate of half a degree centigrade of warming per decade, vegetation may not keep up. Climatologist James Hansen predicts climate zones will shift toward the poles by 50 to 75 kilometers a year--faster than trees can naturally migrate. Species that find themselves in an unfamiliar environment will die. The 1000-kilometer-wide strip of forest running through Canada, Russia, and Scandinavia could be cut by half. Millions of dying trees would soon lead to massive forest fires, releasing tons of CO2 and further boosting global warming. There are dozens of other possible "feedback mechanisms". Higher temperatures will fuel condensation and increase cloudiness, which may actually damp down global warming. Others, like the "albedo" effect is the amount of solar energy reflected by the earth’s surface. As northern ice and snow melts and the darker sea and land pokes through, more heat will be absorbed, adding to the global temperature increase. Even if we were to magically stop all greenhouse-gas emissions tomorrow the impact on global climate would continue for decades. Delay will simply make the problem worse. The fact is that some of us are doing quite well the way things are. In the developed world prosperity has been built on 150 years of cheap fossil fuels. Material progress has been linked to energy consumption. Today 75 percent of all the world’s energy is consumed by a quarter of the world’s population. The average rich-world resident adds about 3.2 tons of CO2 yearly to the atmosphere, more than four times the level added by each Third World citizen. The US, with just seven percent of the global population, is responsible for 22 percent of global warming. It can be inferred from the passage that ______.
Many people seem to think that science fiction is typified by the covers of some of the old pulp magazines: the Bug-Eyed Monster, embodying every trait and feature that most people find repulsive, is about to grab, and presumably ravish, a sweet, blonde, curvaceous, scantily-clad Earth girl. This is unfortunate because it demeans and degrades a worthwhile and even important literary endeavor. In contrast to this unwarranted stereotype, science fiction rarely emphasizes sex, and when it does, it is more discreet than other contemporary fiction. Instead, the basic interest of science fiction lies in the relation between man and his technology and between man and the universe. Science fiction is a literature of change and a literature of the future, and while it would be foolish to claim that science fiction is a major literary genre at this time, the aspects of human life that it considers make it well worth reading and studying ——for no other literary form does quite the same things. The question is: what is science fiction And the answer must be, unfortunately, that there have been few attempts to consider this question at any length or with much seriousness; it may well be that science fiction will resist any comprehensive definition of its characteristics. To say this, however, does not mean that there are no ways of defining it nor that various facets of its totality cannot be clarified. To Begin, the following definition should be helpful: science fiction is a literary sub-genre which postulates a change (for human beings) from conditions as we know them and follows the implications of these changes to a conclusion. Although this definition will necessarily be modified and expanded, and probably changed, in the course of this exploration, it covers much of the basic groundwork and provides a point of departure. The first point ——that science fiction is a literary sub-genre ——is a very important one, but one which is often overlooked or ignored in most discussions of science fiction. Specifically, science fiction is either a short story or a novel. There are only a few dramas which could be called science fiction, with Karel Capek’s RUR (Rossum’s Universal Robots) being the only one that is well known; the body of poetry that might be labeled science fiction is only slightly larger. To say that science fiction is a sub-genre of prose fiction is to say that it has all the basic characteristics and serves the same basic functions in much the same way as prose fiction in general ——that is, it shares a great deal with all other novels and short stories. Everything that can be said about prose fiction, in general applies to science fiction. Every piece of science fiction, whether short story or novel, must have a narrator, a story, a plot, a setting, character, language, and theme. And like any prose, the themes of science fiction are concerned with interpreting man’s nature and experience in relation to the world around him. Themes in science fiction are constructed and presented in exactly the same ways that themes are dealt with in any other kind of fiction. They are the result of a particular combination of narrator, story, plot, character, setting, and language. In short, the reasons for reading and enjoying science fiction, and the ways of studying and analyzing it, are basically the same as they would be for any other story or novel. The view of science fiction encouraged by pulp magazines, while wrong, is nevertheless ______.
"Refrigerator production in China jumped from 1.4 million units in 1985 to 10.6 million in 1998," according to David Fridley, a researcher in the Department of Energy’s Lawrence Berkeley National Laboratory, USA. The Global Environmental Facility, through the United :Nations Development Program, has decided to fund ＄ 9.3 million of the ＄40 million program to help the government of China transform its market for refrigerators. The refrigerator project began in 1989 when the EPA signed an agreement with the government of China to assist in the elimination of CFCs from refrigerators. Berkeley Lab has been involved in the project since 1995 through the U.S. Environmental Protection Agency, developing the market transformation program based on the success of the first phase of the project, which involved designing and testing CFC (chlorofluorocabon) free, energy-efficient refrigerators. Fridley says that beyond his technical supervisory role, the Laboratory will be involved in training and working with the State Bureau of Technical Supervision as the new efficiency standards are developed. "Market transformation," Fridley explains, "is the process of shifting consumer demand for a product, in this case to a more energy-efficient, environmentally favorable product through voluntary, market based means such as technical assistance and training for manufacturers, consumer education, and financial incentives to manufacture and sell the more efficient products." "Collectively, we developed a technical training program for Chinese refrigerator manufacturers interested in developing CFC free, efficient refrigerators; a financial incentive program to motivate manufacturers to build the most efficient refrigerator possible; and a mass purchasing program for Chinese government agencies that acquire refrigerators in bulk," Fridley says. In 1998, the refrigerator project was awarded an International Climate Protection Award by the EPA. "It is not widely known in the United States, but China has had an energy efficiency policy in place since the early 1980s, says Mark Levine, Environmental Energy Technologies Division director and an advisor to the Chinese government on energy efficiency." The government of China is committed to using energy more efficiently, and this has allowed the economy to grow at nearly twice the rate of energy consumption. "The Energy-Efficient Refrigerator Project will have a significant, direct effect on reducing greenhouse gas and pollutant emissions. We Berkeley Lab are grateful to have the chance to work with the people and government of China on this project, as well as on our other refrigerator production projects in energy data analysis, appliance efficiency standards, and technical advice on cogeneration plants ," adds Levine. From what the two American researchers said we can conclude that ______.
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