The food irradiation process is a simple one. The new U.S. plant, Vindicator of Florida Incorporated in Mulberry, Fla., uses a material called cobalt 60 to irradiate food. Cobalt 60 is radioactive isotope (form) of the metallic element cobalt. Cobalt 60, which gives off radiation in the form of gamma rays, is also used for radiation therapy for cancer patients and for sterilizing hospital equipment. The radioactive isotope is created by bombarding cobalt with subatomic particles in a nuclear reactor. However, irradiation plants do not themselves contain nuclear reactors.
In the irradiation plant, food is exposed to thin rods of cobalt 60. The rods give off gamma rays, which disrupt chemical processes in contaminating organisms. The disruption breaks down the cell walls of organisms or destroys their genetic material. The dose, set by the U.S. Food and Drug Administration (FDA), is enough to kill organisms on food, but not enough to produce significant changes in the food itself.
Although irradiation slightly decreases the nutritive value of foods, the loss is less than that produced by some other methods of food preservation. Canning, for example, results in a much greater loss of nutrients.
Those who object to irradiation say that the process may create substances not found in nonirradiated food. Since the 1960’s researchers have studied irradiated food at microscopic levels to try to find such substances, called unique radiolytic products. After reviewing these studies, the FDA determined that compounds formed during irradiation are similar to substance found in nonirradiated foods and are not dangerous to consume.
Destruction of microorganisms that cause illness is an important goal of irradiation. About 250 million cases of food poisoning or 1 per person—occur every year in the U.S., according to FDA estimates. Food poisoning can cause vomiting, diarrhea, fever, headache—and, occasionally, death.
Because of the apparent safety of food irradiation, and the problems presented by contaminated food, scientific groups—including the American Medical Association, the World Health Organization, and the United Nations food and Agriculture Association—have voiced nearly universal support for the process. Worldwide, 38 nations have approved irradiation for 355 products.
Like microwave ovens, food irradiation has aroused apprehension and misunderstanding. Yet it has been scrutinized more thoroughly than other methods of food treatment that we have come to regard as safe, and it appears to be a method whose time has come.
1.Cobalt 60, besides irradiating food, is also employed to ___. A.detect metallic flaws B.run a nuclear reactor C.cure cancer patients D.strengthen concrete walls
2.Gamma rays used to irradiate food ___. A.are generally not strong enough to destroy contaminating organisms B.do not bring about significant changes in the food itself C.may destroy some of the nutrients in the food D.should be submitted to FDA for approval
3.Irradiated food ___. A.certainly loses its nutritive value B.maintains its nutritive value no different from the nonirradiated C.keeps its nutritive value better than canned food D.is recommended as the best of all preserved foods
4.With cases of food poisoning increasing, ___. A.food irradiation should be carried out with care B.it is more urgent to irradiate foods C.medical researches into treatment of the diseased should be strengthened D.Americans are beginning to accept food irradiation
5.The passage may be taken from ___. A.a news report B.a textbook of food processing C.a book of popular science D.a manual of food irradiation
第53篇答案：CBCCD
第54篇：(Unit 14,Passage 2)
Until recently, women in advertisements wore one of three things—an apron, a glamorous dress or a frown. Although that is now changing, many women still feel angry enough to deface offending advertisements with stickers protesting, “This ad degrades women.” Why does this sort of advertising exist? How can advertisers and ad agencies produce, sometimes, after months of research, advertising that offends the consumer?
The Advertising Standards Authority (the body which deals with complaints about print media) is carrying out research into how women feel about the way they are portrayed in advertisements. Its conclusions are likely to be what the advertising industry already knows: although women often irritated by the way they are seen in ads, few feel strongly enough to complain.
Women are not the only victims of poor and boring stereotypes—in many TV commercials men are seen either as useless, childish oafs who are unable to perform the simplest household tasks, or as in considerate boors, permanently on the lookout for an escape to the pub. But it is women who seem to bear the brunt of the industry’s apparent inability to put people into an authentic present-day context.
Yet according to Emma Bennett, executive creative director of a London advertising agency, women are not infuriated by stereotypes and sexist advertising. It tends to wash over them, they are not militant or angry—they just find it annoying or tiresome. They reluctantly accept outdated stereotypes, but heave a sigh of relief when an advertisement really gets it right. She says that it is not advertising’s use of the housewife role that bothers women, but the way in which it is handles. “Researchers have often asked the wrong questions. The most important thing is the advertisement’s tone of voice. Women hate being patronized, flattered or given desperately down-to-earth commonsense advice.”
In the end, the responsibility for good advertising must be shared between the advertiser, the advertising agency and the consumer. Advertising does not set trends but it reflects them. It is up to the consumer to tell advertisers where they fail, and until people on the receiving end take the business seriously and make their feelings known, the process of change will remain laboriously slow.
1.Despite recent changes in attitudes, some advertisements still fail to ___. A.change women’s opinions of themselves B.show any understanding of people’s feelings C.persuade the public to buy certain products D.meet the needs of the advertising industry
2.According to the writer, the commonest fault of present day advertising is to ___. A.condemn the role of the housewife B.ignore protests about advertisements C.present a misleading image of women D.misrepresent the activities of men
3.Research suggests that the reaction of women towards misrepresentation by advertisement is ___. A.apathy B.hostility C.approbation D.unbelief
4.Emma Bennett suggests that advertisement ought to ___. A.give further emphasis to practical advice B.change their style rather than their content C.use male images instead of female ones D.pay more compliments to women than before
5.Ultimately the advertising industry should ___. A.take its job more earnestly B.do more pioneering work C.take notice of the public opinion D.concentrate on the products advertised.
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