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某施工单位承建某大厦工程，总建筑面积30 000ms，该工程位于市中心，现场场地狭窄。施工单位为降低成本，现场只设置了一条3m宽的施工道路兼作消防通道。现场平面呈长方形，其斜对角布置了两个消火栓，两者之间相距70m，其中一个距拟建建筑物3m，另一个距边3m。 屋面板的耐火极限合理的是 。
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Is anti-white bias a problem A new study says whites think discrimination against them is a bigger problem than anti-black bias. They feel threatened by "【C1】______racism". In what some have called the new post-racial era, what constitutes discrimination is【C2】______. A new study has found that Americans think significant progress has been made in the fight【C3】______anti-black bias. But white Americans【C4】______that progress as coming at their【C5】______and that anti-white bias has become a more【C6】______social problem than anti-black bias. White Americans see blacks" progress as a(n) 【C7】______of their status. Is this finding surprising Do we see this view【C8】______in government policies or court decisions If so, how Our recent research【C9】______that white and black Americans agree that bias against blacks was【C10】______in the 1950"s and 1960"s. And many Americans support the march【C11】______full and equal rights for all. 【C12】______when blacks see such racism as continuing, whites【C13】______to see it as a problem that has been more or less "solved". Many whites now believe that it"s anti-white bias that"s on a rise, to the point where it"s even more【C14】______than anti-black bias. Why would the perception of anti-white bias have increased【C15】______among whites, particularly in recent years The answer is still【C16】______. What is certain is that this【C17】______is a danger to the nation. In fact, for all the gains of the civil rights movement, blacks【C18】______among the poorest, most isolated and most unemployed of all Americans. But such reality is【C19】______to white fellow citizens who are【C20】______instead by fantasies of competitive victimhood. 【C17】
Eat More, Weigh Less, Live Longer Clever genetic detective work may have found out the reason why a near starvation diet prolongs the life of many animals. Ronald Kahn at Harvard Medical School in Boston, US, and his colleagues have been able to extend the lifespan (寿命) of mice by 18 per cent by blocking the rodent’s (啮齿动物) increase of fat in specific cells. This suggests that thinness—and hot necessarily diet—promotes long life in "calorie (热量卡) restricted" animals. "It’s very cool work." says aging researcher Cynthia Kenyon of the University of California, San Francisco. "These mice eat all they want, lose weight and live longer. It’s like heaven." Calorie restriction dramatically extends the lifespan of organisms as different as worms and rodents. Whether this works in humans is still unknown, partly because few people are willing to submit to such a strict diet. But many researchers hope they will be able to trigger the same effect with a drug once they understand how less food leads to a longer life. One theory is that eating less reduces the increase of harmful things that can damage cells. But Kahn’s team wondered whether the animals simply benefit by becoming thin. To find out, they used biology tricks to disrupt the insulin (胰岛素) receptor (受体) gene in lab mice—but only in their fat cells. "Since insulin is needed to help fat cells store fat, these animals were protected against becoming fat," explains Kahn. This slight genetic change in a single tissue had dramatic effects. By three months of age, Kahn, those modified mice had up to 70 per cent less body fat than normal control mice, despite the fact that they ate 55 per cent more food per gram of body weight. In addition, their lifespan increased. The average control mouse lived 753 days, while the thin rodents averaged a lifespan of 887 days. After three years, all the control mice had died, but one—quarter of the modified rodents were still alive. "That they get these effects by just manipulating the fat cells is controversial," says Leonard Guarente of the Massachusetts Institute of Technology, who studies calorie restriction and aging. But Guarente says Kahn has yet to prove that the same effect is responsible for increased lifespan in calorie, restricted animals. "It might be the same effect or there might be two routes to long life," he points out, "and that would be very interesting." Ronald Kahn and his colleagues can make mice live longer by ______.
In recent decades, scientists have become increasingly aware of the part the observer【C1】______in the scientific process. In the【C2】______place, the observer can work only with his experiences, and these are【C3】______by his senses and the instruments he【C4】______to extend his senses. Ultraviolet light, electromagnetic fields, and atomic particles, 【C5】______. became known to us only as we devised tools【C6】______we could observe their effects. 【C7】______, our picture of the real world is always incomplete. Secondly, the observer is highly selective in choosing his【C8】______. Life is a narrative of ever new and often【C9】______events. At any given moment, an individual is bombarded with sense experiences and can, 【C10】______he desires, expose himself to more. But he is really interested in or concerned with only a few of these. Other experiences are consciously or【C11】______ screened out as irrelevant to the task【C12】______. For example, as we read a book, we are often surrounded by sounds and activities that we【C13】______ , but by turning our attention to them we become conscious of their presence. What a scientist discovers depends, 【C14】______, on what he is looking for—【C15】______the questions he is asking. Thus, academic disciplines differ in their study of human beings in large part【C16】______they ask different questions. Human beings live, 【C17】______, in a house with only a few windows of tinted and curved glass, 【C18】______which we see the outside world. The glass colors and distorts our observations, and its effects can be determined only with【C19】______difficulty. Scientists are increasingly aware of the【C20】______that they work with sense data, not with the world itself. 【C12】
In recent decades, scientists have become increasingly aware of the part the observer【C1】______in the scientific process. In the【C2】______place, the observer can work only with his experiences, and these are【C3】______by his senses and the instruments he【C4】______to extend his senses. Ultraviolet light, electromagnetic fields, and atomic particles, 【C5】______. became known to us only as we devised tools【C6】______we could observe their effects. 【C7】______, our picture of the real world is always incomplete. Secondly, the observer is highly selective in choosing his【C8】______. Life is a narrative of ever new and often【C9】______events. At any given moment, an individual is bombarded with sense experiences and can, 【C10】______he desires, expose himself to more. But he is really interested in or concerned with only a few of these. Other experiences are consciously or【C11】______ screened out as irrelevant to the task【C12】______. For example, as we read a book, we are often surrounded by sounds and activities that we【C13】______ , but by turning our attention to them we become conscious of their presence. What a scientist discovers depends, 【C14】______, on what he is looking for—【C15】______the questions he is asking. Thus, academic disciplines differ in their study of human beings in large part【C16】______they ask different questions. Human beings live, 【C17】______, in a house with only a few windows of tinted and curved glass, 【C18】______which we see the outside world. The glass colors and distorts our observations, and its effects can be determined only with【C19】______difficulty. Scientists are increasingly aware of the【C20】______that they work with sense data, not with the world itself. 【C9】
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