2010年大学英语四六级考试精读荟萃100篇(41)英语六级考试
文章作者 100test 发表时间 2010:04:28 21:06:45
来源 100Test.Com百考试题网
Passage Eleven (The Affect of Electricity on Cancer)
Can electricity cause cancer? In a society that literally runs on electric power, the very idea seems preposterous. But for more than a decade, a growing band of scientists and journalists has pointed to studies that seem to link exposure to electromagnetic fields with increased risk of leukemia and other malignancies. The implications are unsettling, to say the least, since everyone comes into contact with such fields, which are generated by everything electrical, from power lines and antennas to personal computers and micro-wave ovens. Because evidence on the subject is inconclusive and often contradictory, it has been hard to decide whether concern about the health effects of electricity is legitimate—or the worst kind of paranoia.
Now the alarmists have gained some qualified support from the U.S. Environmental Protection Agency. In the executive summary of a new scientific review, released in draft form late last week, the EPA has put forward what amounts to the most serious government warning to date. The agency tentatively concludes that scientific evidence “suggests a casual link” between extremely low-frequency electromagnetic fields—those having very longwave-lengths—and leukemia, lymphoma and brain cancer, While the report falls short of classifying ELF fields as probable carcinogens, it does identify the common 60-hertz magnetic field as “a possible, but not proven, cause of cancer in humans.”
The report is no reason to panic—or even to lost sleep. If there is a cancer risk, it is a small one. The evidence is still so controversial that the draft stirred a great deal of debate within the Bush Administration, and the EPA released it over strong objections from the Pentagon and the Whit House. But now no one can deny that the issue must be taken seriously and that much more research is needed.
At the heart of the debate is a simple and well-understood physical phenomenon: When an electric current passes through a wire, tit generates an electromagnetic field that exerts forces on surrounding objects, For many years, scientists dismissed any suggestion that such forces might be harmful, primarily because they are so extraordinarily weak. The ELF magnetic field generated by a video terminal measures only a few milligauss, or about one-hundredth the strength of the earth’s own magnetic field, The electric fields surrounding a power line can be as high as 10 kilovolts per meter, but the corresponding field induced in human cells will be only about 1 millivolt per meter. This is far less than the electric fields that the cells themselves generate.
How could such minuscule forces pose a health danger? The consensus used to be that they could not, and for decades scientists concentrated on more powerful kinds of radiation, like X-rays, that pack sufficient wallop to knock electrons out of the molecules that make up the human body. Such “ionizing” radiations have been clearly linked to increased cancer risks and there are regulations to control emissions.
But epidemiological studies, which find statistical associations between sets of data, do not prove cause and effect. Though there is a body of laboratory work showing that exposure to ELF fields can have biological effects on animal tissues, a mechanism by which those effects could lead to cancerous growths has never been found.
The Pentagon is for from persuaded. In a blistering 33-page critique of the EPA report, Air Force scientists charge its authors with having “biased the entire document” toward proving a link. “Our reviewers are convinced that there is no suggestion that (electromagnetic fields) present in the environment induce or promote cancer,” the Air Force concludes. “It is astonishing that the EPA would lend its imprimatur on this report.” Then Pentagon’s concern is understandable. There is hardly a unit of the modern military that does not depend on the heavy use of some kind of electronic equipment, from huge ground-based radar towers to the defense systems built into every warship and plane.
1. The main idea of this passage is
[A]. studies on the cause of cancer
[B]. controversial view-points in the cause of cancer
[C]. the relationship between electricity and cancer.
[D]. different ideas about the effect of electricity on caner.
2. The view-point of the EPA is
[A]. there is casual link between electricity and cancer.
[B]. electricity really affects cancer.
[C]. controversial.
[D].low frequency electromagnetic field is a possible cause of cancer
3. Why did the Pentagon and Whit House object to the release of the report? Because
[A]. it may stir a great deal of debate among the Bush Administration.
[B]. every unit of the modern military has depended on the heavy use of some kind of electronic equipment.
[C]. the Pentagon’s concern was understandable.
[D]. they had different arguments.
4. It can be inferred from physical phenomenon
[A]. the force of the electromagnetic field is too weak to be harmful.
[B]. the force of the electromagnetic field is weaker than the electric field that the cells generate.
[C]. electromagnetic field may affect health.
[D]. only more powerful radiation can knock electron out of human body.
5. What do you think ordinary citizens may do after reading the different arguments?
[A].They are indifferent. [B]. They are worried very much.
[C]. The may exercise prudent avoidance. [C]. They are shocked.
Vocabulary
1. preposterous 反常的,十分荒谬的,乖戾的
2. leukemia 白血病
3. malignancy 恶性肿瘤
4. legitimate 合法的,合理的
5. paranoia 偏执狂,妄想狂。这里指:无根据的担心。
6. lymphoma 淋巴瘤
7. carcinogen 致癌物
8. minuscule 很小的,很不重要
9. consensus 舆论
10. wallop 乱窜,猛冲,冲击力
11. epidemiological 流行病学的
12. blistering 罗嗦的,胡扯的
13. critique 评论,批评
14. imprimatur 出版许可(官方审查后的),批准
难句译注
1. Because evidence on the subject is inconclusive and often contradictory, it has been hard to decide whether concern about the health effects of electricity is legitimate—or the worst kind of paranoia.
[参考译文] 由于这问题的证据还不是结论性的,而且常常是矛盾的,所以就难以断定有关电力对身体的影响的顾虑是合乎情理,还是毫无根据的怀疑。
2. EPA——U.S. Environmental Protection Agency 美国环境保护署
3. While the report falls short (缺乏,不够) of classifying ELF fields as probable carcinogens, it does identify the common 60-hertz magnetic field as “a possible, but not proven, cause of cancer in humans.”
[参考译文] 虽然报告没有把极低频磁场归类为可能致癌物,但它确实指出通常60赫兹的磁场是“一种虽尚未证实,但可能导致人患癌症的因素。”
4. The evidence is still so controversial that the draft stirred a great deal of debate within the Bush Administration, and the EPA released it over strong objections from the Pentagon and the Whit House
[参考译文] 证据争议性仍然很大,所以报告草案在布什政府内引起巨大的争辩,而环保署无视无角大楼和白宫的强烈反对,公布了这份报告。
5. This is far less than the electric fields that the cells themselves generate.
[参考译文] 这远比细胞所产生的电磁场低的多。
6. …and for decades scientists concentrated on more powerful kinds of radiation, like X-rays, that pack sufficient wallop to knock electrons out of the molecules that make up the human body.
[参考译文] 而且几十年来,科学家专注于更为强大的辐射类别,如X光射线,其聚合的冲击力足以把电子从组成人体的分子中撞出来。
7. But epidemiological studies, which find statistical associations between sets of data, do not prove cause and effect.
[参考译文] 可是流行病学的研究发现,几组资料在数据方面有所关联,却没有证实其因果关系。
8. a body of laboratory work 一批研究成果。
9. In a blistering 33-page critique of the EPA report, Air Force scientists charge its authors with having “biased the entire document” toward proving a link.
[参考译文] 在长达33页的对环保署文件的十分尖锐的批评中,空军方面的科学家指责,作者歪曲整个文件以证明癌症和电磁场之间的关联。
10. It is astonishing that the EPA would lend its imprimatur on this report.
[参考译文] 令人惊讶的是环保署竟然批准许可这份报告的出笼。