单选题Last summer, some twenty-eight thousand homeless people were afforded shelter by the city of New York. Of this number, twelve thou sand were children and six thousand were parents living together in families. The average child was six years old, the average parent twenty seven. A typical homeless family included a mother with two or three children, but in about one-fifth of these families two parents were present. Roughly ten thousand single persons, then, made up the remainder of the population of the city' s shelter. These proportions vary somewhat from one area of the nation to another. In all areas, however, families are the fastest-growing sector of the homeless population, and in the Northeast they are by far the largest sector already. In Massachusetts, three-fourths of the homeless now are families with children; in certain parts of Massachusetts-Attleboro and Northampton, for example-the proportion reaches 90percent. Two thirds of the homeless children studied recently in Boston were less than five years old. Of the estimated two to three million homeless people nationwide, about 500,000 are dependent children, according to Robert Hayes, counsel to the National Coalition for the homeless. Including their parents, at least 750,000 homeless people in America are family members. What is to be made, then, of the supposition that the homeless are primarily the former residents of mental hospitals, persons who were carelessly released during the 1970s? Many of them are, to be sure. Among the older men and women in the streets and shelters, as many as one-third ( some believe as many as one-half) may be chronically disturbed, and a number of these people left mental hospitals during the 1970s. But in a city like New York, where nearly half the homeless are small children with an average of six, to operate on the basis of such a supposition makes no sense. Their parents, with an average age of twenty-seven, are not likely to have been hospitalized in the 1970s, either.

单选题{{B}}Text 2{{/B}} Scientists have for the first time used cloning to create human embryos that live long enough in a laboratory dish to have their stem cells harvested. The feat could set the stage for physicians to produce cells and tissues, tailored to a patient's genetic identity that can treat a wide variety of human illnesses. The accomplishment also provides a road map for how to clone a person, an even more divisive undertaking. The new work, performed in South Korea, represents "a major advance in stem cell research. It could help spur a medical revolution as important as antibiotics and vaccines", says Robert Lanza of Advanced Cell Technology (ACT), a company in Worcester, Mass., that's also investigating the promising stem cell strategy called therapeutic cloning. "However, now that the methodology is publicly available", Lanza adds, "I think it is absolutely imperative that we pass laws worldwide to prevent the technology from being abused for reproductive-cloning purposes." While some fertility doctors and a religious cult have claimed success at creating a pregnancy via cloning, they've offered no convincing proof. In contrast, the South Korean research is being reported at the meeting of the American Association for the Advancement of Science in Seattle and will appear in an upcoming Science. "This is reality," says stem cell researcher John Gearhart of Johns Hopkins University. "He4'e is a bona fide, refereed journal saying that a human embryo has been cloned and a cell line derived from it." Although ACT has not yet published a report of a cloned human blastocyst, Lanza says that the South Korean success is "consistent with our own results." Therapeutic cloning appeals to Lanza and physicians because cells made this way could have the same DNA as a patient's cells do and thus avoid rejection after they're transplanted. Seeking a compromise that would permit this strategy to be pursued, many scientists have called for legislation that would ban cloning to produce a baby but allow the creation of cloned embryos to generate stem cells for research or therapies. "The debate has been very polarized," notes bio-ethicist Laurie Zoloth of Northwestern University in Evanston.

单选题It is only in recent years that we have recognized that

单选题If one travels on the Mediterranean cruise in the future,

单选题In an ideal world, the nation's elite schools would enroll the most qualified students. But that's not how it (1) .Applicants whose parents are alums get special treatment, as (2) athletes and rich kids. Underrepresented minorities are also given (3) . Thirty years of affirmative action have changed the character of (4) white universities; now about 13 percent of all undergraduates are black or Latino. (5) a recent study by the Century Foundation found that at the nation's 146 most (6) schools, 74 percent of students came from upper middle-class and wealthy families, while only about 5 percent came from families with an annual income of (7) $ 35,000 or less. Many schools say diversity--racial, economic and geographic--is (8) to maintaining intellectually (9) campuses. But Richard Kahlenberg of the Century Foundation says that even though colleges (10) they want poor kids, "they don't try very hard to find them." (11) rural students, many colleges don't try at all. "Unfortunately, we go where we can (12) a sizable number of potential applicants," says Tulane admissions chief Richard Whiteside, who (13) aggressively and in person--from metropolitan areas. Kids in rural areas get a glossy (14) in the mail. Even when poor rural students have the (15) for top colleges, their high schools often don't know how to get them there. Admissions officers (16) guidance counselors to direct them to promising prospects. In (17) high schools, guidance counselors often have personal (18) with both kids and admissions officers. In rural areas, a teacher, a counselor or (19) an alumnus "can help put a rural student on our radar screen," says Wesleyan admissions dean Nancy Meislahn. But poor rural schools rarely have college (20) with those connections; without them, admission "can be a crapshoot," says Carnegie Mellon's Steidel.

单选题The first technological revolution in modern biology started when James Watson and Francis Crick described the structure of DNA half a century ago. That established the fields of molecular and cell biology, the basis of the biotechnology industry. The sequencing of the human genome nearly a decade ago set off a second revolution which has started to illuminate the origins of diseases. Now the industry is convinced that a third revolution is under way: the convergence of biology and engineering. A recent report from the Massachusetts Institute of Technology says that physical sciences have already been transformed by their adoption of information technology, advanced materials, imaging, nanotechnolugy and sophisticated modelling and simulation. Phillip Sharp, a Nobel prize-winner at that university, believes that those tools are about to be brought to bear on biology too. But the chances are that this will take time, and turn out to be more of a reformation than a revolution. The conventional health-care systems of the rich world may resist new technologies even as poor countries leapfrog ahead. There is already a backlash against genomics, which has been oversold to consumers as a deterministic science. And given soaring health-care costs, insurers and health systems may not want to adopt new technologies unless inventors can show conclusively that they will produce better outcomes and offer value for money. If these obstacles can be overcome, then the biggest winner will be the patient. In the past medicine has taken a paternalistic stance, with the all-knowing physician dispensing wisdom from on high, but that is becoming increasingly untenable. Digitisation promises to connect doctors not only to everything they need to know about their patients but also to other doctors who have treated similar disorders. That essential reform will enable many other big technological changes to be introduced. Just as important, it can make that information available to the patients too, empowering them to play a bigger part in managing their own health affairs. This is controversial, and with good reason. Many doctors, and some patients, reckon they lack the knowledge to make informed decisions. But patients actually know a great deal about many diseases, especially chronic ones like diabetes and heart problems with which they often live for many years. The best way to deal with those is for individuals to take more responsibility for their own health and prevent problems before they require costly hospital visits. That means putting electronic health records directly into patients’ hands.

单选题Global warming is something

单选题According to Anne Krueger, long-term government protection given to steel companies

单选题According to the passage, Sommer

单选题Macdonald began his attack on plans for secret terror trials

单选题In recent years American society has become increasingly dependent on its universities to find solutions to its major problems. It is the universities that have been charged with the principal responsibility for developing the expertise to place men on the moon; for dealing with our urban problems and with our deteriorating environment; for developing the means to feed the world's rapidly increasing population. The effort involved in meeting these demands presents its own problems. In addition, this concentration on the creation of new knowledge significantly impinges on the universities' efforts to perform their other principal functions, the transmission and interpretation of knowledge the imparting of the heritage of the past and the preparing of the next generation to carry it forward. With regard to this, perhaps their most traditionally sanctioned task, colleges and universities today find themselves in a serious hind generally. On the one hand, there is the American commitment, entered into especially since WW 1I, to provide higher education for all young people who can profit from it. The result of the commitment has been a dramatic rise in enrollments in our universities, coupled with a radical shift from the private to the public sector of higher education. On the other hand, there are serious and continuing limitations on the resources available for higher education. While higher education has become a great "growth industry", it is also simultaneously a tremendous drain on the resources of nation. With the vast increase in enrollment and the shift in priorities away from education in state and federal budgets, there is in most of our public institutions a significant decrease in per capita outlay for their students, one crucial aspect of this drain on resources lies in the persistent shortage of trained faculty, which has led, in rum, to a declining standard of competence in instruction. Intensifying these difficulties is, as indicated above, the concern with research, with its competing claims on resources and the attention of the faculty. In addition, there is a strong tendency for the institutions; organization and functioning to conform to the demands of research rather than those of teaching.

单选题Which of the following is NOT mentioned in the passage as a function of electronics in television transmissions?

单选题We can infer that the key feature of Ningbo campus of Nottingham University is that