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In recent years a new farming revolution has begun, one that involves the manipulation of life at a fundamental level—the gene. The study of genetics has (51) a new industry called biotcehnology. As the name suggests, it (52) biology and modern technology through such techniques as genetic engineering. Some of the new biotech companies specialize in agriculture and are working feverishly to (53) seeds that give a high yield, that (54) diseases, drought and frost, and that reduce the need for hazardous chemicals, If such goals could be achieved, it would be most (55) . But some have raised concerns about genetically engineered crops. In nature, genetic diversity is created within certain (56) . A rose can be crossed with a different kind of rose, but a rose will never cross with a potato. Genetic engineering, (57) usually involves taking genes from one species and inserting them into another in an attempt to transfer a desired characteristic. This could mean, for example, selecting a gene which leads to the production of a chemical with anti-freeze (58) from an artic fish, and inserting it into a potato or strawberry to make it frost, resistant, in essence, then, biotechnology allows humans to (59) the genetic walls that separate species. Just like the green revolution, (60) some call the gene revolution contributes to the problem of genetic uniformity-some say even more so (61) geneticists can employ techniques such as cloning and (62) culture (培养) and processes that produce perfectly (63) copies. Concerns about the erosion of biodiversity, therefore, remain. Genetically altered plants, however, raise new (64) ,such as the effects that they may have on us and the environment. "We are tlying blindly into a new era of agricultural biotechnology with high hopes, few constraints, and little idea of the potential (65) ," said science writer Jeremy Rifkin.
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Don’t Treat Animals as Furry Test-tubes Most of us agree that there is a moral obligation to minimize the suffering of any captive animals. In addition, there are numerous self-serving reasons why we should respect the welfare of our captive companions. However, the impact of poor animal welfare on the quality of animal science always concerns a scientist the most. Rodents(灵长类动物) make up over 80% of the animals used in scientific procedures, and most are kept in small, barren cages. Such housing is known to constrain normal development, affecting the structure and function of adult rodent brains. These rodents may spend 50% of waking hours performing repetitive activities without apparent purpose. This abnormal behavior is likely to reflect what is going on inside the body. As ethnologist Hanno Wfirbel, of the Justus Liebig University of Giessen, Germany, puts it," The point that the environment might change behavior but it doesn’t change biology is ridiculous. Every behavior has a physiological background." If welfare affects behavior, and therefore biology, it will affect scientific outcomes. As long as we continue to treat experimental animals as simple" furry test-tubes", ignoring their abilities and needs, we endanger the quality of the work we do with them. So, how can we improve life for other species when we cannot experience it as they do We’d better ask the animals. Ask them what they need, and what causes them suffering, through carefully designed preference tests and in-depth behavioural research. Scientists have already begun this task, and have been told some important and unexpected facts by their study subjects. By consistently self-medicating with pain killers, broiler chickens (嫩鸡) have told us that they are in chronic pain. By moving a barrier twice their size, mink (水貂) have told us that water baths are the most important enrichment for them. By only stopping their fruitless stereotypic digging in certain circumstances, gerbils(沙鼠) have told us that they need to be able to sleep in tunneled nest-boxes. By behaving normally again, starlings have told us that they need high frequency light bulbs. What is the author’s attitude towards the way most experimental animals are treated
Intelligent car door clamps up when danger’s about Accidents caused by car doors being opened into the path of oncoming vehicles or cyclists are common in cities. But these incidents could become a thing of the past, if doors that react to potential impacts catch on. The creative idea of Michael Graf at BMW and Michael Strolz’s team at the Technical University of Munich, the "haptic"-technology that gives tactile feedback-doors could cut both road injuries and repair bills, they say. The current prototype looks like a normal car door, but an extra metal bar runs through its centre and connects to the car’s frame between the hinges. In normal mode, the bar moves freely and doesn’t affect the door’s movement. However, if sensors detect a nearby obstacle at the same time as an accelerometer detects an attempt to open the door, the door’s swing is restricted by a linear motor attached to the bar. To pass on more information to the user, the amount of door resistance is in proportion to the proximity of an object-for example, you might swing a door halfway open without problems before it gets stiffer as it nears a lamp post. The current prototype uses supersonic sensors to spot dangers, but because they have a limited field of view, the next version will use cameras that can span 180°, says Strolz. "Then we will be able to sense the complete workspace of the door and detect people walking by the car or cycling towards it," he says. Reactions from 16 volunteers who tried the new door at BMW’s Munich research centre have been encouraging, the team told a recent conference on haptics in Salt Lake City, Utah. The technology is mature enough that a car factory could be pumping it out in cars within a year, says Strolz. The basic mechanism is like one already featured in some cars-for example, taxis with automatic passenger doors. However, BMW is yet to make any decision on whether to roll it out. How did the volunteers who tried the new door at BMW respond to it
Passage 3 Not too many decades ago it seemed "obvious" both to the general public and to sociologists that modern society has changed people’s natural relations, loosened their responsibilities to kin and neighbors, and substituted in their place superficial relationships with passing acquaintances. However, in recent years a growing body of research has revealed that the "obvious" is not true. It seems that if you are a city resident, you typically know a smaller proportion of your neighbors than you do if you are a resident of a smaller community. But, for the most part, this fact has few significant consequences. It does not necessarily follow that if you know few of your neighbors you will know no one else. Even in very large cities, people maintain close social ties within small, private social worlds. Indeed, the number and quality of meaningful relationships do not differ between more and less urban people. Smalltown residents are more involved with kin that are big-city residents. Yet city dwellers compensate by developing friendships with people who share similar interests and activities. Urbanism may produce a different style of life, but the quality of life does not differ between town and city. Nor are residents of large communities any likelier to display psychological symptoms of stress or alienation, a feeling of not belonging, than are residents of smaller communities. However, city dwellers do worry more about crime, and this leads them to a distrust of strangers. These findings do not imply that urbanism makes little or no difference. If neighbors are strangers to one another, they are less likely to sweep the sidewalk of an elderly couple living next door or keep an eye out for size and its social heterogeneity. For instance, sociologists have found much evidence that the size of more likely than their small-town counterparts to have a cosmopolitan outlook, to display less responsibility to traditional kinship roles, to vote for leftist political candidates, and to be tolerant of nontraditional religious groups, unpopular political groups, and so-called undesirables. Everything considered, heterogeneity and unusual behavior seem to be outcomes of large population size. What is the passage mainly about
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