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In 1967, in response to widespread public concern aroused by medical reports of asbestos(石棉绒) related deaths, NMRC organized a committee of enquiry to investigate the health threats ,associated with the use of asbestos in the building industry. After examining evidences provided by medical researchers and building workers and management, NMRC published a report, which included advices for dealing with asbestos. The report confirmed the findings of similar research in the U. S. and Canada. Exposure to relatively small quantities of asbestos fibers, they concluded, was directly responsible for the development of cancers, asbestosis and related diseases. Taking into account evidence provided by economists and building industry management, however, the report assumed that despite the availability of other materials, asbestos would continue to play a major role in the British building industry for many years to come because of its availability and low cost. As a result, NMRC gave a series of recommendations, which were intended to reduce the risks to those who might be exposed to asbestos in working environments. They recommended that, where possible, asbestos-free materials should be employed. In cases where asbestos was employed, it was recommended that it should be used in such a way that loose fibers were less likely to enter the air. The report recommended that special care should be taken during work in environments which contain asbestos. Workers should wear protective equipment and take special care to remove dust from the environment and clothing with the use of vacuum cleaner. The report identified five factors which determine the level of risk involved. The state and type of asbestos is critical to determining the risk factors. In addition, dust formation was found to be limited where the asbestos was used when wet rather than dry. A critical factor takes place in risk reduction is the adequate ventilation of the working environment. When work takes place in an enclosed space, more asbestos particles circulate and it was therefore recommended that natural or machine ventilation should be used. By closely following these advices, it was claimed that exposure can be reduced to a reasonably practical minimum. Exposure to asbestos fibers can cause cancer _________.
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Questions 11 to 18 are based on the conversation you have just heard.
TEXT A Like land, labor is means of production. In non-industrial societies, access to both land and labor comes through social links such as kinship, marriage, and descent. Mutual aid in production is merely one aspect of ongoing social relationships that are expressed on many other occasions. Non-industrial societies contrast with industrial nations in regard to another means of production — technology. In bands and tribes manufacturing is often linked to age and gender. Women may weave and men make pottery or vice versa. Most people of a particular age and gender share the technical knowledge associated with that age and gender. If married women customarily make baskets, most married women know how to make baskets. Neither technology nor technical knowledge is as specialized as it is in states. However, some tribal societies do promote specialization. Among the Yanomani of Benezuela and Brazil, for instance, certain villages manufacture clay pots and others make hammocks. They don’t specialize, as one might suppose, because certain raw materials happen to be available near particular village. Clay suitable for pots is widely available. Everyone knows how to make pots, but not everybody does so. Craft specialization reflects the social and political environment rather than the natural environment. Such specialization promotes trade, which is the first step in creating an alliance with enemy village. Specialization contributes to keeping the peace, although it has not prevented intervillage warfare. Among the Trobriand Islanders of the South Pacific, Malinowski found that only two out of several villages manufactured certain ceremonial items that were important in a regional exchange network called the kula ring. As among the Yanomani, this specialization was unrelated to the location of raw materials. We don’t know why this specialization began, but we do know that it persisted within the kula ring, which allied several communities and islands in a common trade network. What does the sentence "manufacturing is often linked to age and gender" mean
TEXT B Every year, 2,000 American lives are saved by the selflessness of others. These are the bone marrow donors who give the gift of life to patients fighting deadly diseases such as leukemia, lymphoma, and aplastic anemia. That’s the good news. The bad news is that thousands more die each year because not enough people have signed on to the registries that would help the ill find a suitable match for a transplant. Bone marrow or stem-cell transplants are usually a last resort, intended for those whose illnesses have not responded to traditional treatments such as chemotherapy or radiation. How do they work We all store a special type of cell in our bone marrow called stem cells. These primitive cells give rise to the three types of blood cells: red, white and platelets. Everyone’s stem cells have certain genetic characteristics or markers that make them unique from others. Despite this uniqueness, there are some shared characteristics between people. This is important, because a patient’s immune system will reject blood or organs received from someone else if they do not share sufficient similarities. Family members, especially siblings, are always the first to be considered as donors, because there’s a greater chance that the genetic markers on their cells will have enough in common to prevent rejection after transplantation. In many cases, however, a familial match can’t be found and then the search begins for an unrelated donor. These donors typically come from a pool of people who have already signed up on a donor registry in the event that their cells match a needy recipient. Once the lab has verified a match between donor and recipient, the next phase starts. The patient is given radiation or chemotherapy to kill the unhealthy cells. Healthy cells are harvested from the donor — either extracted from the pelvic bones or taken from the arm in a way that is similar to having blood drawn — and prepared in a laboratory. Once they’re ready, they’re given to the patient through a vein — the same way as one would receive a blood transfusion. Once these transplanted donor cells get settled within the patient’s bone marrow, they make the healthy red blood cells, white blood cells and platelets necessary to support life. One of the major problems currently faced by transplant centers is that while bonemarrow transplants can cure more than 70 different diseases, there aren’t enough donors on the registry to treat the more than 3,000 patients awaiting transplants. The National Marrow Donor Program, the largest registry in the country, has approximately 4.8 million adult volunteer donors, but that isn’t nearly enough for the thousands who need transplants. Why isn’t a pool of more than 4 million donors isn’t enough to cover 3,000 needy patients Here’s the reason: in the vast-majority of cases, finding a suitable match isn’t easy. Because we are unique individuals with a variety of ancestral backgrounds and integration patterns, finding someone similar to us is a major task. In the end, it comes down to a numbers game — the more potential donors listed on the registry, the greater a chance of finding a match, especially for those with unusual genetic characteristics. The author cited the example of 4. g million volunteer donors in America to justify ______.
The American war on drugs has gotten all the type in recent years, but alcoholism is still the nation’s most serious (36) . True, casual drinking is no longer as (37) as it once was. But alcoholism’s toll remains (38) high: Some 18 million Americans (39) alcohol, and more than 100,000 die prematurely each year from alcohol-related causes. And alcoholism costs the nation $86 billion a year. Business picks up most of the tab. Virtually every company has workers with a drinking problem, often veteran employees in (40) or other critical positions. When their alcoholism goes (41) , it costs a bundle. Problem drinkers don’t (42) their weight in the office, are often chronically late or absent, and file $4600 more in health (43) a year than other employees. Their families’ doctor bills are much higher, too. Meanwhile, the company pays full salary and benefits for an employee who is fully functional only some of the time. (44) . But now the progress against Corporate America’s biggest drug problem is being threatened. Although few companies are eliminating alcohol treatment benefits entirely, many are hiring outside vendors to manage care (45) . This is bad business. Limiting treatment may seem to save money. But the one-time expense of helping an alcoholic recover is a fraction of the long-term potential cost. (46) .
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