单选题Whitening the world's roofs would offset the emissions of the world's cars for 20 years, according to a new study from Lawrence Berkeley National Laboratory. Overall, installing lighter-colored roofs and pavements can cancel the heat effect of two years of global carbon dioxide emissions, Berkeley Lab says. It's the first roof-cooling study to use a global model to examine the issue. Lightening up roofs and pavement can offset 57 billion metric tons of carbon dioxide, about double the amount the world emitted in 2006, the study found. It was published in the journal Environmental Research Letters. Researchers used a conservative estimate of increased albedo, or solar reflection, suggesting that purely white roofs would be even better. They increased the albedo of all roof by 0. 25 and pavement by 0. 15. That means a black roof, which has an albedo of zero, would only need to be replaced by a roof of a cooler color — which might be more feasible to implement than a snowy white roof. Berkeley Lab says. The researchers extrapolated a roof's CO 2 offset over its average lifespan. If all roofs were converted to white or cool colors, they would offset about 24 gigatons (24 billion metric tons) of CO 2 , but only once. But assuming roofs last about 20 years, the researchers came up with 1. 2 gigatons per year. That equates to offsetting the emissions of roughly 300 million cars, all the in the world, for 20 years. Pavements and roofs cover 50 to 65 percent of urban areas and cause a heat-island effect because they absorb so much heat. That's why cities are significantly warmer than surrounding rural areas. This effect makes it harder—and therefore more expensive — to keep buildings cool in the summer. Winds also move the heat into the atmosphere, causing a regional warming effect. Energy secretary Steven Chu, a Nobel Laureate in physics (and former Berkeley Lab director), has advocated white roofs for years. He put his words into actions by directing all Energy Department offices to install white roofs. All newly installed roofs will be white, and black roofs might be replaced when it is cost-effective over the lifetime of the roof. "Cool roofs are one of the quickest and lowest-cost ways we can reduce our global carbon emissions and begin the hard work of slowing climate change. " He said in a statement.

单选题Whether the cause is maternal anti-bodies, heavy metals or something else, there is no question that the brains of young children with autism have unusual features. To begin with, they tend to be too big. In studies based on magnetic resonance imaging(MRI)and basic tape-measure readings , neuroscientist Eric Courchesne at Children" s Hospital of San Diego showed that while children with autism are born with ordinary-size brains, they experience a rapid expansion by age 2—particularly in the frontal lobes. By age 4, says Courchesne, autistic children tend to have brains the size of a normal 13-year-old. More recent studies by Admiral and others have found that the amygdale, an area associated with social behavior, is also oversize, a finding Admiral believes is related to the high levels of anxiety seen in as many as 80% of people with autism. Harvard pediatric neurologist Dr. Martha Herbert reported last year that the excess white matter in autistic brains has a specific distribution; local areas tend to be over connected, while links between more distant regions of the brain are weak. The brain" s right and left hemispheres are also poorly connected. It" s as if there are too many competing local services but no long distance. This observation jibes neady with imagining studies that look at live brain activity in autistic people. Studies using functional MRI show a lack of coordination among brain regions, says Marcel Just, director of Carnegie Mellon" s Center for Cognitive Brain Imaging in Pittsburgh, Pa. Just has scanned dozens of 15-to-35-year-old autistic people with IQs in the normal range, giving them thinking tasks as he monitors their brain activity. " One thing you see," says Just, " is that activity in different areas is not going up and down at the same time. There" s a lack of synchronization, sort of like a difference between a jam session and a string quartet. In autism, each area does its own thing. " What remains unclear is whether the interconnectivity problem is the result of autism or its cause. "It" s impossible to tell the chicken from the egg at this point," Just says. Autistic people have been shown to use their brains in unusual ways; they memorize alphabet characters in apart of the brain that ordinarily processes shapes. They tend to use the visual centers in the back of the brain for tasks usually handled by the prefrontal cortex. They often look at the mouth instead of the eyes of someone who is speaking. Their focus, says psychologist Ami Klin of Yale" s Child Study Center, is " not on the social allegiances—for example, the longing gaze of a mother—but physical allegiances—a mouth that moves. "

单选题Beyond the basic animal instincts to seek food and avoid pain, Freud identified two sources of psychic energy, which he called "drives": aggression and libido. The key to his theory is that these were unconscious drives, shaping our behavior without the mediation of our waking minds; they surface, heavily disguised, only in our dreams. The work of the past half-century in psychology and neuroscience has been to downplay the role of unconscious universal drives, focusing instead on rational processes in conscious life. But researchers have found evidence that Freud's drives really do exist, and they have their roots in the limbic system, a primitive part of the brain that operates mostly below the horizon of consciousness. Now more commonly referred to as emotions, the modern suite of drives comprises five: rage, panic, separation distress, lust and a variation on libido sometimes called seeking. The seeking drive is proving a particularly fruitful subject for researchers. Although like the others it originates in the limbic system, it also involves parts of the forebrain, the seat of higher mental functions. In the 1980s, Jaak Panksepp, a neurobiologist at Bowling Green State University in Ohio, became interested in a place near the cortex known as the ventral tegmental area, which in humans lies just above the hairline. When Panksepp stimulated the corresponding region in a mouse, the animal would sniff the air and walk around, as though it were looking for something. Was it hungry? No. The mouse would walk right by a plate of food, or for that matter any other object Panksepp could think of. This brain tissue seemed to cause a general desire for something new. "What I was seeing, " he says, "was the urge to do stuff. " Panksepp called this seeking. To neuropsychologist Mark Solms of University College in London, that sounds very much like libido. "Freud needed some sort of general, appetitive desire to seek pleasure in the world of objects, " says Solms. "Panksepp discovered as a neuroscientist what Freud discovered psychologically. " Solms studied the same region of the brain for his work on dreams. Since the 1970s, neurologists have known that dreaming takes place during a particular form of sleep known as REM — rapid eye movement — which is associated with a primitive part of the brain known as the pons. Accordingly, they regarded dreaming as a low-level phenomenon of no great psychological interest. When Solms looked into it, though, it turned out that the key structure involved in dreaming was actually the ventral tegmental, the same structure that Panksepp had identified as the seat of the "seeking" emotion. Dreams, it seemed, originate with the libido—which is just what Freud had believed. Freud's psychological map may have been flawed in many ways, but it also happens to be the most coherent and, from the standpoint of individual experience, meaningful theory of the mind. "Freud should be placed in the same category as Darwin, who lived before the discovery of genes, " says Panksepp. "Freud gave us a vision of a mental apparatus. We need to talk about it, develop it, test it. " Perhaps it's not a matter of proving Freud wrong or right, but of finishing the job.

单选题The men set off in silence. Pedro walked with his dog a few paces behind the boys. When neighbors saw them walking along in this formation they would say that Pedro looked like a veritable patron striding behind his peons. Yet there were mornings when Pedro talked to the boys in the course of their two-hour walk to the fields, giving advice or telling what work had to be done. The boys, however, spoke only in answer to a question. Out of their father" s earshot they would joke about their sweethearts or visits to the saloons of Cuahnahuac. But this morning they moved silently down the road. It was still barely light. All around them, just beyond the far edges of the fields, the blue-green slopes of the pine-covered mountains rose through the morning mist. Pedro and Ricardo were headed for the mountain slope cornfield which they had cleared the year before. This was communal land belonging to the municipality which consisted of seven villages; anyone could work it. New clearings had to be made every two or three years, for heavy rains washed the topsoil away. To acquire new fields Pedro and his sons burned the brush and weeds, cut down young trees, and built new stone fences. The boys worked well; they had the largest mountain clearing in Azteca. But the crops could supply enough corn and beans for only three or four months. So Pedro had to try other means of earning a living as well — making rope from maguey fiber, selling plums, hiring out his sons as farm hands. One thing he would not do to earn money was to make charcoal for sale, as so many of his neighbors did. This practice, he knew, was wasteful of the precious oak and pine forests and ultimately ruined land. He had been one of the leaders in the struggle for the preservation of the communal forest lands. So he made charcoal only once a year and only for the use of his family.

单选题For the past several years, the Sunday newspaper supplement Parade has featured a column called "Ask Marilyn." People are invited to query Marilyn vos Savant, who at age 10 had tested at a mental level of someone about 23 years old; that gave her an IQ of 228-the highest score ever recorded. IQ tests ask you to complete verbal and visual analogies, to envision paper after it has been folded and cut, and to deduce numerical sequences, among other similar tasks. So it is a bit confusing when vos Savant fields such queries from the average Joe(whose IQ is 100)as, What"s the difference between love and fondness? Or what is the nature of luck and coincidence? It"s not obvious how the capacity to visualize objects and to figure out numerical patterns suits one to answer questions that have eluded some of the best poets and philosophers. Clearly, intelligence encompasses more than a score on a test. Just what does it mean to be smart? How much of intelligence can be specified, and how much can we learn about it from neurology, genetics, computer science and other fields? The defining term of intelligence in humans still seems to be the IQ score, even though IQ tests are not given as often as they used to be. The test comes primarily in two forms: the Stanford-Binet Intelligence Scale and the Wechsler Intelligence Scales(both come in adult and children"s version). Generally costing several hundred dollars, they are usually given only by psychologists, although variations of them populate bookstores and the World Wide Web. Superhigh scores like Vos Savant"s are no longer possible, because scoring is now based on a statistical population distribution among age peers, rather than simply dividing the mental age by the chronological age and multiplying by 100. Other standardized tests, such as the Scholastic Assessment Test(SAT)and the Graduate Record Exam(GRE), capture the main aspects of IQ tests. Such standardized tests may not assess all the important elements necessary to succeed in school and in life, argues Robert J. Sternberg. In his article "How Intelligent Is Intelligence Testing?" Sternberg notes that traditional test best assess analytical and verbal skills but fail to measure creativity and practical knowledge, components also critical to problem solving and life success. Moreover, IQ test do not necessarily predict so well once populations or situations change. Research has found that IQ predicted leadership skills when the tests were given under low-stress conditions, but under high-stress conditions, IQ was negatively correlated with leadership-that is, it predicted the opposite. Anyone who has toiled through SAT will testify that test-taking skill also matters, whether it knows when to guess or what questions to skip.

单选题The biggest problem facing Chile as it promotes itself as a tourist destination to be reckoned with, is that it is at the end of the earth. It is too far south to be a convenient stop on the way to anywhere else and is much farther than a relatively cheap half-day"s flight away from the big tourist markets, unlike Mexico, for example. Chile, therefore, is having to fight hard to attract tourists, to convince travelers that it is worth coming halfway round the world to visit. But it is succeeding, not only in existing markets like the USA and Western Europe but in new territories, in particular the Far East. Markets closer to home, however, are not being forgotten. More than 50% of visitors to Chile still come from its nearest neighbor, Argentina, where the cost of living is much higher. Like all South American countries, Chile sees tourism as a valuable earner of foreign currency, although it has been far more serious than most in promoting its image abroad. Relatively stable politically within the region, it has benefited from the problems suffered in other areas. In Peru, guerrilla warfare in recent years has dealt a heavy blow to the tourist industry and fear of street crime in Brazil has reduced the attraction of Rio de Janeiro as a dream destination for foreigners. More than 150,000 people are directly involved in Chile"s tourist sector, an industry which earns the country more than US $ 950 million each year. The state-run National Tourism Service, in partnership with a number of private companies, is currently running a worldwide campaign, taking part in trade fairs and international events to attract visitors to Chile. Chile"s great strength as a tourist destination is its geographical diversity. From the parched Atacama Desert in the north to the Antarctic snowfields of the south, it is more than 5,000km long. With the Pacific on one side and the Andean mountains on the other, Chile boasts natural attractions. Its beaches are not up to Caribbean standards but resorts such as Vina del Mar are generally clean and unspoilt and have a high standard of services. But the tromp card is the Andes mountain range. There are a number of excellent ski resorts within one hour"s drive of the capital, Santiago, and the national parks in the south are home to rare animal and plant species. The parks already attract specialist visitors, including mountaineers, who come to climb the technically difficult peaks, and fishermen, lured by the salmon and trout in the region"s rivers. However, infrastructural development in these areas is limited. The ski resorts do not have as many lifts and pistes as their European counterparts and the poor quality of roads in the south means that only the most determined travelers see the best of the national parks. Air links between Chile and the rest of the world are, at present, relatively poor. While Chile"s two largest airlines have extensive networks within South America, they operate only a small number of routes to the United States and Europe, while services to Asia are almost non-existent. Internal transport links are being improved and luxury hotels are being built in one of its national parks. Nor is development being restricted to the Andes. Easter Island and Chile"s Antarctic Territory are also on the list of areas where the Government believes it can create tourist markets. But the rush to open hitherto inaccessible areas to mass tourism is not being welcomed by everyone. Indigenous and environmental groups, including Greenpeace, say that many parts of the Andes will suffer if they become over-developed. There is a genuine fear that areas of Chile will suffer the cultural destruction witnessed in Mexico and European resorts. The policy of opening up Antarctica to tourism is also politically sensitive. Chile already has permanent settlements on the ice and many people see the decision to allow tourists there as a political move, enhancing Santiago"s territorial claim over part of Antarctica. The Chilean Government has promised to respect the environment as it seeks to bring tourism to these areas. But there are immense commercial pressures to exploit the country"s tourism potential. The Government will have to monitor developments closely if it is genuinely concerned in creating a balanced, controlled industry and if the price of an increasingly lucrative tourist market is not going to mean the loss of many of Chile"s natural riches.

单选题On September 7, 2001, a 68-year-old woman in Strasbourg, France, had her gall bladder (胆囊) removed by-surgeons operating, via computer from New York. It was the first complete telesurgery procedure performed by surgeons nearly 4 000 miles away from their patient. In New York, Marescaux teamed up with surgeon Michel Gagner to perform the historic long-distance operation. A high-speed fiber-optic service provided by France Telecom made the connection between New York and Strasbourg. The two surgeons controlled the instruments using an advanced robotic surgical system, designed by Computer Motion Inc. that enabled the procedure to be minimally invasive. The patient was released from the hospital after about 48 hours and regained normal activity the following week. The high-speed fiber-optic connection between New York and France made it possible to overcome a key obstacle to telesurgery time delay. It was crucial that a continuous time delay of less than 200 milliseconds be maintained throughout the operation, between the surgeon' s movements in New York and the return video (from Strasbourg) on his screen. The delay problem includes video coding decoding and signal transmission time. France Telecom' s engineers achieved an average time delay of 150 milliseconds. " I felt as comfortable operating on my patient as if I had been in the room," says Marescaux. The successful collaboration (合作) among medicine, advanced technology, and telecomm unications is likely to have enormous implications for patient care and doctor training. Highly skilled surgeons may soon regularly perform especially difficult operations through long-distance procedures. The computer systems used to control surgical movement can also lead to a breakthrough in teaching surgical techniques to a new generation of physicians. More surgeons-in-training will have the opportunity to observe their teachers in action in telesurgery operating rooms around the world. Marescaux describes the success of the remotely performed surgical procedure as the beginning of a "third revolution" in surgery within the last decade. The first was the arrival of minimally invasive surgery, enabling procedures to be performed with guidance by a camera, meaning that the abdomen (腹部) and thorax (胸腔) do not have to be opened. The second was the introduction of computer-assisted surgery, where complicated software algorithms(计算法)enhance the safety of the surgeon's movements during a procedure, making them more accurate, while introducing the concept of distance between the surgeon and the patient. It was thus natural to imagine that this distance-currently several meters in the operating room could potentially be up to several thousand kilometers.

单选题When people are struck by lightening, they fall to the ground as though they were struck by a severe blow to the head. After the shock they may remain unconscious, become semiconscious or be conscious but confused and dazed, at least for a time. Flashes of light may continue passing before their eyes, and blindness and deafness may follow. The nervous system may be badly affected, causing paralysis, pain in the limbs and even hemorrhage. There will be burns where the lightening passed through the body, and like all electrical bunts, they are often deep and sever. All persons, especially campers and hunters, should know how to give first aid to someone who has been struck by lightening. Do not be afraid to touch the victim. You won"t get a shock. The lightening has already been grounded. Remember that speed is of the greatest importance in severe cases. The first thing to do is to loosen tight clothing about the throat and waist. Then clear the air passages of mucus(黏液)if present, and apply artificial respiration if necessary. Give mouth-mouth resuscitation if needed, or give oxygen if available. Many victims thought to be dead have been revived after treatment. Send someone for a doctor as soon as possible, but don"t leave the victim alone. If a doctor is not available, take the person to a hospital as soon as the person can be safely moved. Signs of shock are: pale, cold, sticky skin; weak, rapid pulse; shallow, irregular breathing or, in extreme cases, no breathing at all. To treat shock, you must keep the patient lying down with the head lower than the feet and cover him or her with a blanket but watch out for overheating. Giving a stimulating hot tea or coffee will help, but only if the patient is thoroughly conscious. After breathing has been restored and shock is treated, treat the burns. Apply some salve and cover them with a clean cloth or a sterile dressing. If conscious, the patient will be badly frightened, so do all you can to reassure. A little knowledge and a helping hand may save someone"s life.

单选题Avian influenza is an infectious disease of birds caused by type A strains of the influenza virus. The disease, which was first identified in Italy more than 100 years ago, occurs worldwide.All birds are thought to be susceptible to infection with avian influenza, though some species are more resistant to infection than others. Infection causes a wide spectrum of symptoms in birds, ranging from mild illness to a highly contagious and rapidly fatal disease resulting in severe epidemics. The latter is known as "highly pathogenic avian influenza". This form is characterized by sudden onset, severe illness, and rapid death, with a mortality that can approach 100%. Fifteen subtypes of influenza virus are known to infect birds, thus providing an extensive reservoir of influenza viruses potentially circulating in bird population. To date, all outbreaks of the highly pathogenic form have been caused by influenza A viruses of subtypes H5 and H7. Migratory waterfowl—most notably wild ducks—are the natural reservoir of avian influenza viruses, and these birds are also the most resistant to infection. Domestic poultry, including chickens and turkeys, are particularly susceptible to epidemics of rapidly fatal influenza. Direct or indirect contact of domestic flocks with wild migratory waterfowl has been implicated as a frequent cause of epidemics. Live bird markets have also played an important role in the spread of epidemics. Recent research has shown that viruses of low pathogenicity can, after circulation for sometimes short periods in a poultry population, mutate into highly pathogenic viruses. During a 1983-1984 epidemic in the United States of America, the H5N2 virus initially caused low mortality, but within six months became highly pathogenic, with a mortality approaching 90%. Control of the outbreak required destruction of more than 17 million birds at a cost of nearly US $65 million. During a 1999-2001 epidemic in Italy, the H7N1 virus, initially of low pathogenicity, mutated within 9 months to a highly pathogenic form. More than 13 million birds died or were destroyed. The quarantining of infected farms and destruction of infected or potentially exposed flocks are standard control measures aimed at preventing spread to other farms and eventual establishment of the virus in a country's poultry population. Apart from being highly contagious, avian influenza viruses are readily transmitted from farm to farm by mechanical means, such as by contaminated equipment, vehicles, feed, cages, or clothing. Highly pathogenic viruses can survive for long periods in the environment, especially when temperatures are low. Stringent sanitary measures on farms can, however, confer some degree of protection. In the absence of prompt control measures backed by good surveillance, epidemics can last for years. For example, an epidemic of H5N2 avian influenza, which began in Mexico in 1992, started with low pathogenicity, evolved to the highly fatal form, and was not controlled until 1995.

单选题The physical distribution of products has two primary aspects: transportation and storage. Both aspects are highly developed and specialized phases of marketing. The costs of both transporting and storing are built into the prices of products. Transportation can be by truck, railways, ship, or barge. For some items, such as exotic plants and flowers, or when rapid delivery is essential, air freight may be used. Storage, or warehousing, is a necessary function because production and consumption of goods rarely match: items generally are not sold as quickly as they are made. Inventories build up, both in warehouses and at retail establishments, before the foods are sold. The transportation function is involved in bringing goods to a warehouse and taking them from it to retail stores. Storage performs the service of stabilizing market price. If, for example, no agricultural product could be stored, all food would have to be put on the market immediately. This would, of course, create a glut and lower prices drastically. There would be an immediate benefit to consumers, but in the long run they would suffer. Farmers, because of low prices, would be forced off the land, and the amount of food produced would decrease. This, in turn, would raise consumer prices. Warehouses for storage are of several types. Private warehouses are owned by manufacturers. Public warehouses, in spite of their name, are privately owned facilities, but they are independent of manufacturer ownership. General-merchandise warehouses store a great variety of products. Cold-storage warehouses store perishable goods, especially food products. Grain elevators are a kind of warehouse used to keep wheat and other grains from spoiling. A bonded warehouse is one that stores foods, frequently imported, on which taxes must be paid before they are sold. Cigarettes and alcoholic beverages are common examples. The distribution center is a more recently developed kind of warehouse. Many large companies have several manufacturing plants, sometimes located outside the country. Each plant does not make every company product but specializes in one or more of them. The distribution center allows a manufacturer to bring together all product lines in one place. Its purpose is to minimize storage and to ease the flow of goods from manufacturers to retailers rather than build up extensive inventories. It reduces costs by speeding up product turnover. Very large corporations will have several distribution centers regionally or internationally based.

单选题It is not unusual for chief executives to collect millions of dollars a year in pay, stock options, and bonuses. In the last fifteen years, while executive remuneration rose, taxed in the highest income bracket went down. Millionaires are now commonplace. Amiability is not a prerequisite for rising to the top, and there are a number of chief executive officers with legendary bad tempers. It is not the boss" job to worry about the well-being of his subordinates although the man with many enemies will be swept out more quickly in hard times; it is the company he worries about. His business savvy is supposed to be based on intimate knowledge of his company and the industry so he goes home nightly with a full briefcase. At the very top—and on the way up—executives are exceedingly dedicated. The American executive must be capable of enough small talk to get him through the social part of his schedule, but he is probably not a highly cultured individual or an intellectual. Although his wife may be on the board of the symphony or opera, he himself has Utile time for such pursuits. His reading may largely concern business and management, despite interests in other fields. Golf provides him with a sportive outlet that combines with some useful socializing. These days, he probably attempts some form of aerobic exercise to "keep the old heart in shape" and for the same reason goes easy on butter and alcohol, and substances thought to contribute to taking highly stressed executives out of the running. But his doctor"s admonition to "take it easy" falls on deaf ears. He likes to work. He knows there are younger men nipping at his heels. Corporate head-hunting, carried on by "executive search firms", is a growing industry. America has great faith in individual talent, and dynamic and aggressive executives are so in demand that companies regularly raid each other"s managerial ranks.

单选题There are many theories about the beginning of drama in ancient Greece. The one most widely accepted today is based on the assumption that drama evolved from ritual. The argument for this view goes as follows. In the beginning, human beings viewed the natural forces of the world, even the seasonal changes, as unpredictable, and they sought through various means, to control these unknown and feared powers. Those measures which appeared to bring the desired results were then retained and repeated until they hardened into fixed rituals. Eventually stories arose which explained or veiled the mysteries of the rites. As time passed some rituals were abandoned, but the stories, later called myths, persisted and provided material for art and drama. Those who believed that drama evolved out of ritual also argue that those rites contained the seed of theater because music, dance, masks, and costumes were almost always used. Furthermore, a suitable site had to be provided for performances, and when the entire community did not participate, a clear division was usually made between the "acting area" and the "auditorium". In addition, there were performers, and, since considerable importance was attached to avoiding mistakes in the enactment of rites, religious leaders usually assumed that task. Wearing masks and costumes, they often impersonated other people, animals, or super natural beings, and mimed the desired effect-success in hunt or battle, the coming rain, the revival of the Sun—as an actor might. Eventually such dramatic representations were separated from religious activities. Another theory traces the theater"s origin from the human interest in storytelling. According to this view, tales(about the hunt, war, or other feats)are gradually elaborated, at first through the use of impersonation, action, and dialogue by a narrator and then through the assumption of each of the roles by a different person. A closely related theory traces theater to those dances that are primarily rhythmical and gymnastic or that are imitations of animal movements and sounds.

单选题California is a land of variety and contrast. Almost every type of physical land feature, sort of arctic ice fields and tropical jungles can be found within its borders. Sharply contrasting types of land often lie very close to one another. People living in Bakersfield, for instance, can visit the Pacific Ocean and the coastal plain, the fertile San Joaquin Valley, the arid Mojave Desert, and the high Sierra Nevada, all within a radius of about 100 miles. In other areas it is possible to go snow skiing in the morning and surfing in the evening of the same day, without having to travel long distance. Contrast abounds in California. The highest point in the United States(outside Alaska)is in California, and so is the lowest point(including Alaska). Mount Whitney, 14,494 feet above sea level, is separated from Death Valley, 282 feet below sea level, by a distance of only 100 miles. The two areas have a difference in altitude of almost three miles. California has deep, clear mountain lakes like Lake Tahoe, the deepest in the country, but it also has shallow, salty desert lakes. It has Lake Tulainyo, 12,020 feet above sea level, and the lowest lake in the country, the Saltan Sea, 236 feet below sea level. Some of its lakes, like Owens Lake in Death Valley, are not lakes at all: they are dried up lake beds. In addition to mountains, lakes, valleys, deserts, and plateaus, California has its Pacific coastline, stretching longer than the coastlines of Oregon and Washington combined.

单选题If you" re among the two-thirds of working women who earn their living in offices, it" s far too early to let out a sigh of relief about how healthy and happy your working environment is. If you are among that number, however, you probably already know that. Without question, office work doesn" t pose the risks or dangers of jobs in manufacturing, mining, or even agriculture. The closest many of us come to working with a chemical is when we get toner smudges on our hands from photocopies or apply dabs of correcting fluid. By most people" s standards, even the dingiest office beats an assembly line, factory, or a mine for atmosphere. A white collar isn" t exactly protective clothing, however. More than 40,000 disabling injuries(including back and neck injuries and muscle pulls)and 200 safety-related deaths occur in offices each year. There are also considerable other stresses associated with office work, including boredom, repetitiveness, and low status, which can affect health. One thing is certain: as the numbers of office workers grow, so too will office health problems. In the 1950s and early 1960s the office had begun its climb to economic fame and power, jockeying into position to replace industry as the largest employer in the United States. It was the beginning of what author John Naisbitt calls the "information age" in his influential book Megatrends, "Now," he says, "more than 65 percent of us work with information as programmers, teachers, clerks, secretaries, accountants, stock brokers, managers, insurance people, bureaucrats, lawyers, bankers, and technicians. And many more workers hold information jobs within manufacturing companies."

单选题Without fanfare or legislation, the government is orchestrating a quiet revolution in how it regulates new medicines. The revolution is based on the idea that the sicker people are, the more freedom they should have to try drugs that are not yet fully tested. For fifty years government policy has been driven by another idea; the fear that insufficiently tested medicines could cause deaths and injuries. The urgent needs of people infected with HIV, the AIDS virus, and the possibility of meeting them with new drugs have created a compelling countervailing force to the continuing concern with safety. As a result, government rules and practices have begun to change. Each step is controversial. But the shift has already gone far beyond AIDS. New ways are emerging for very sick people to try some experimental drugs before they are marketed. People with the most serious forms of heart disease, cancer, emphysema, Alzheimer" s or Parkinson" s disease, multiple sclerosis, epilepsy , diabetes, or other grave illnesses can request such drugs through their doctors and are likelier to get them than they would have been four years ago. " We" ve been too rigid in not making life-saving drugs available to people who otherwise face certain death," says Representative Henry Wax-man, of California, who heads the subcommittee that considers changes in drug-approval policies. "It" s true of AIDS, but it" s also true of cancer and other life-threatening diseases. " For the first time, desperate patients have become a potent political force for making new medicines available quickly. People with AIDS and their advocates, younger and angrier than most heart-disease or cancer patients, are drawing on two decades of gay activists" success in organizing to get what they want from politicians. At times they found themselves allied with Reagan Administration deregulators, scientists, industry representatives, FDA staff members, and sympathetic members of Congress. They organized their own clinical trials and searched out promising drugs here and abroad. The result is a familiar Washington story; a crisis—AIDS—helped crystallize an informal coalition for reform. AIDS gave new power to old complaints. As early as the 1970s the drug industry and some independent authorities worried that the Food and Drug Administration" s testing requirements were so demanding that new drugs were being unreasonably delayed. Beginning in 1972, several studies indicated that the United States had lost its lead in marketing new medicines and that breakthrough drugs, those that show new promise in treating serious or life—threatening diseases—had come to be available much sooner in other countries. Two high-level commissions urged the early release of breakthrough drugs. So did the Carter Administration, but the legislation it proposed died in Congress. Complaints were compounded by growing concern that "if we didn" t streamline policies, red tape would be an obstacle to the development of the biotechnology revolution," as Frank E. Young, who was the head of the FDA from 1984 to 1989, put it in an interview with me. Young was a key figure in the overhaul of the FDA" s policies. A pioneer in biotechnology and a former dean of the University of Rochester" s medical school, he came to Washington with an agenda and headed the agency for five and a half years—longer than anyone else has since the 1960s. Young took the FDA job to help introduce new medicines created by biotechnology—whose promise he had seen in his own gene-cloning lab and to get experimental medicines to desperately ill people more quickly. He had seen people die waiting for new medicines because " they were in the wrong place at the wrong time," he said. That is now changing.

单选题While traveling for various speaking engagements, I frequently stay overnight in the home of a family and am invited to one of the children's bedrooms. In it, I often find so many playthings that there's almost no room. And the closet is usually so tightly packed with clothes that I can barely squeeze in my jacket. I' m not complaining, only making a point. I think that the tendency to give children an overabundance (过多) of toys and clothes is quite common in American families, and I think that in far too many families not only do children come to take their parents' generosity for granted, but also the effects of this can actually be somewhat harmful to children. Of course, I' m not only thinking of the material possessions children are given. Children can also be overindulged (过分宠爱) with too many privileges—for example, when parents send a child to an expensive summer camp that the parents can't really afford. Why? One fairly common reason is that parents overindulge their children out of a sense of guilt. Parents who both hold down full-time jobs may feel guilty about the amount of time they spend away from their children and may attempt to compensate by showering them with material possessions. Overindulgence of a child also happens when parents are unable to stand up to their children's unreasonable demands. Such parents vacillate between saying no and giving in—but neither response seems satisfactory to them. If they refuse a request, they immediately feel a wave of remorse for having been so strict or ungenerous. If they give in, they feel regret and resentment over having been a pushover. This kind of vacillation not only impairs the parents' ability to set limits, it also sours the parent-child relationship to some degree, robbing parents and their children of some of the happiness and mutual respect that should be present in healthy families. But overindulging children with material things does little to lessen parental guilt (since parents never feel that they've given enough), nor does it make children feel more loved (for what children really crave is parents' time and attention). Instead, the effects of overindulgence can be harmful. Children may, to some degree become greedy, self-centered, ungrateful and insensitive to the needs and feelings of others, beginning with their parents. When children are given too much, their respect for their parents would be undermined.

单选题For months Gina Cruz, a Manila grandmother, played Pepsi Cola' s "Numbers Fever" promotion lottery, buying several bottles a day and saving the caps, in the hope that one of the magic number, imprinted inside them would win her a 1 million peso($40,000)prize. When the magic number, 349 was announced in May 1992, Cruz was overjoyed to find she had not one, but two caps bearing the winning digits. She promptly fainted. " My blood pressure shot up," she explained later, "probably from drinking too much Pepsi. " Then she learned that her son also had a 349 cap—and she nearly collapsed again. Cruz' s indignation after discovering the next day that she was not, after all, a double millionaire , is shared by thousands of contestants who feel equally cheated. Instead of marking out 18 winning numbers, on which Pepsi had planned, a computer had wrongly generated 800,000. The company explained that it simply did not have the $ 32 billion it would take to pay all claimants. The real winners, it said, would be identified by a security code that had been placed on caps; the losers were offered apologies. When Pepsi' s explanation was not accepted, a promotion that initially boosted the company' s market share by 5% turned into a nightmare. The winners felt like losers of a second, surprise lottery; the security code had been publicized as an authentication tool, not as a necessary second winning number. Feeling hoodwinked, the players have banded together in protest groups, fanning anti-Pepsi flames at frequent demonstrations and marches. More than 22,000 people holding the 349 number have filed 689 civil suits seeking damages, as well as 5,200 criminal complaints alleging fraud and deception. Some Pepsi employees have received death threats and now change their daily routines to avoid being attacked. Explosives have been thrown at Pepsi plants and offices, and 37 of the company' s delivery trucks have been stoned, overturned or set on fire. In the worst incident , a school-teacher and a five-year-old girl were killed last. February when a grenade pitched at a Pepsi truck bounced off and exploded in front of a store.

单选题Neuroscientists now understand at least some of the physiology behind a wide range of unconscious states, from deep sleep to coma, from partially conscious conditions to a persistent vegetative state, the condition diagnosed in Ms. Schiavo. New research, by laboratories in New York and Europe, has allowed for much clearer distinctions to be made between the uncounted number of people who at some time become comatose, the 10,000 to 15,000 Americans who subsist in vegetative states and the estimated 100,000 or more who exist in states of partial consciousness. This emerging picture should make it easier for doctors to judge which brain-damaged patients have some hope of recovering awareness, experts say, and already it is providing clues to the specific brain processes that sustain conscious awareness. "Understanding what these processes are will give us a better sense of how to help the whole range of people living with brain injuries," said Dr. Nicholas Schiff, an assistant professor of neurology and neuroscience at NewYork-Presbyterian / Weill Cornell hospital. "That is where this field is ultimately headed: toward a better understanding of what consciousness is." The most familiar unconscious state is sleep, which in its deepest phases is characterized by little electrical activity in the brain and almost complete unresponsiveness. Coma, the most widely known state of impaired unconsciousness, is in fact a continuum. Doctors rate the extent to which a comatose person shows pain responses and reactions to verbal sounds on a scale from 3, for no response, to 13, for consistent responses. As in sleep, people in comas may move or make sounds and typically have no memory of either. But they almost always emerge from this state in two to three weeks, doctors say, when the eyes open spontaneously. What follows is critical for the person"s recovery. Those who are lucky, or who have less severe injuries, gradually awaken. "The first thing I remember was telling my ex-boyfriend, who was at the foot of the bed, to shut up," said Trisha Meili, who fell into a coma after being beaten and raped in 1990, and wrote about the experience in the book, I Am the Central Park Jogger. In the days after this memory, Ms. Meili said, she slipped in and out of conscious awareness, "as if my body was taking care of the most important things first, and leaving my moment to moment awareness for last." In fact, researchers say, this is precisely what happens. The primitive brain stem, which controls sleep-wake cycles as well as reflexes, asserts itself first, as the eyes open. Ideally, areas of the cerebral cortex, the seat of conscious thought, soon follow, like lights flicking on in the upper rooms of a darkened house. But in some cases — Ms. Schiavo"s was one of them — the cortical areas fail to engage, and the patient"s prognosis becomes dire. Neurologists were all but unanimous in diagnosing the condition of Ms. Schiavo, whose heart stopped temporarily in 1990, depriving her brain of oxygen. Brain cells and neural connections wither and die without oxygen, like marine life in a drained lake, leaving virtually nothing unharmed. People with these kinds of injuries—Nancy Cruzan, whose case reached the Supreme Court in 1990 is an example — almost always remain unresponsive if they have not regained awareness in the first months after the injury. In medical terms, they become persistently vegetative, a diagnosis first described in 1972 by Dr. Fred Plum of Cornell University and Dr. Bryan Jennett, a neurosurgeon at Glasgow University in Scotland. In a sense, the description of the diagnosis began the modern study of disorders of consciousness. "Before 1972 people talked about permanent comas, or irrecoverable comas, but we defined a different state altogether, with the eyes open, some reflex activity, but no sign of meaningful psychological responsiveness," Dr. Jennett, now a professor emeritus, said in an interview. In an exhaustive review of the medical histories of more than 700 persistently vegetative patients, a team of doctors in 1994 reported that about 15 percent of those who suffered brain damage from oxygen deprivation, like Ms. Schiavo, recovered some awareness within three months. After that, however, very few recovered and none did so after two years. About 52 percent of people with traumatic wounds to the head, often from car accidents, recovered some awareness in the first year after the injury, the study found; very few recovered after that. "It"s the difference between taking a blow to the brain, which affects a local area — and taking this global, whole-brain hit," said Dr. Joseph Fins, chief of the medical ethics division of NewYork-Presbyterian / Weill Cornell hospital. Yet these statistics cannot explain the stories of remarkable recovery that surfaced during the debate over Ms. Schiavo"s fate. There was Terry Wallis, a mechanic in Arkansas who regained awareness in 2003, more than 18 years after he fell into unconsciousness from a car accident; Sarah Scantlin, a Kansas woman who, also a victim of a car accident, emerged from a similar state after 19 years; and several others, whose collective human spirit seemed to defy the experts, and trump science. Researchers say these cases can be accounted for by recent studies that indicate the existence of yet another state of subdued responsiveness, one that represents a clear break from the vegetative.

单选题Relaxing isn"t easy. I know — I have tried it. I can see, therefore, why Japan"s government should want corporations to have full-time "leisure advisers". It seems an idea worth copying. A start should, perhaps, be made at the very top. Captains of industry often find it hardest of all to relax. Some buy a luxurious yacht, a beach house, or even an island, but seldom make use of these expensive leisure facilities. "I don"t have time for a holiday," they insist. What they usually mean is not that they couldn"t find the time, if pressed, but that they don"t want to. More often than not the plain truth is that they don"t know how to ease up. No one has ever told them how to do it. You can"t be a frantic executive one day and a leisurely beachcomber the next, the contrast is too great. But a captain of industry on a beach and he tends to get bored and restless. He misses the pace, the action. Invite him to play tennis and he will probably decline, because he fears that he will look foolish —he prefers to play games in the office, where he is a proven winner. If he has a holiday home, or stays in a plush hotel, he will be on the telephone six times a day, doing what he does best. So what can a "leisure adviser" do for him—or, increasingly, her? The basic task is to change attitudes, and gradually to introduce him to various leisure activities. A good start is to persuade him that holidays are a "psychological investment", and that it is perfectly feasible to combine business with pleasure. They can take work with them. For a captain of industry, holidays are ideal of strategic planning. They can call the office, though the aim must be to reduce the number of calls as the holiday progresses. They can be persuaded to take up golf. It is not only a pleasant and healthy way of going for a leisurely walk, but it can also be good for business. Once the initial leisure training period has been completed you can try to hook him on other activities which are every bit as challenging as a take-over bid. He can climb mountains, ride river rapids, go scuba diving. He may well end up making a happy discovery; leisure can be fun.

单选题This month Singapore passed a bill that would give legal teeth to the moral obligation to support one"s parents. Called the Maintenance of Parents Bill, it received the backing of the Singapore Government. That does not mean it hasn"t generated discussion. Several members of the Parliament opposed the measure as un-Asian. Others who acknowledged the problem of the elderly poor believed it a disproportionate response. Still others believe it will subvert relations within the family: cynics dubbed it the "Sue Your Son" law. Those who say that the bill does not promote filial responsibility, of course, are right. It has nothing to do with filial responsibility. It kicks in where filial responsibility fails. The law cannot legislate filial responsibility any more than it can legislate love. All the law can do is to provide a safety net where this morality proves insufficient. Singapore needs this bill not to replace morality, but to provide incentives to shore it up. Like many other developed nations, Singapore faces the problems of an increasing proportion of people over 60 years of age. Demography is inexorable. In 1980, 7.2% of the population was in this bracket. By the end of the century that figure will grow to 11%. By 2030, the proportion is projected to be 26%. The problem is not old age per se. It is that the ratio of economically active people to economically inactive people will decline. But no amount of government exhortation or paternalism will completely eliminate the problem of old people who have insufficient means to make ends meet. Some people will fall through the holes in any safety net. Traditionally, a person"s insurance against poverty in his old age was his family, lifts is not a revolutionary concept. Nor is it uniquely Asian. Care and support for one"s parents is a universal value shared by all civilized societies. The problem in Singapore is that the moral obligation to look after one"s parents is unenforceable. A father can be compelled by law to maintain his children. A husband can be forced to support his wife. But, until now, a son or daughter had no legal obligation to support his or her parents. In 1989, an Advisory Council was set up to look into the problems of the aged. Its report stated with a tinge of complacency that 95% of those who did not have their own income were receiving cash contributions from relations. But what about the 5% who aren"t getting relatives" support? They have several options:(a)get a job and work until they die;(b)apply for public assistance(you have to be destitute to apply); or(c)starve quietly. None of these options is socially acceptable. And what if this 5% figure grows, as it is likely to do, as society ages? The Maintenance of Parents Bill was put forth to encourage the traditional virtues that have so far kept Asian nations from some of the breakdowns encountered in other affluent societies. This legislation will allow a person to apply to the court for maintenance from any or all of his children. The court would have the discretion to refuse to make an order if it is unjust. Those who deride the proposal for opening up the courts to family lawsuits miss the point. Only in extreme cases would any parent take his child to court. If it does indeed become law, the bill"s effect would be far more subtle. First, it will reaffirm the notion that it is each individual"s—not society"s—responsibility to look after his parents. Singapore is still conservative enough that most people will not object to this idea. It reinforces the traditional values and it doesn"t hurt a society now and then to remind itself of its core values. Second, and more important, it will make those who are inclined to shirk their responsibilities think twice. Until now, if a person asked family elders, clergymen or the Ministry of Community Development to help get financial support from his children, the most they could do was to mediate. But mediators have no teeth, and a child could simply ignore their pleas. But to be sued by one"s parents would be a massive loss of face. It would be a public disgrace. Few people would be so thick-skinned as to say, "Sue will be damned." The hand of the conciliator would be immeasurably strengthened. It is far more likely that some sort of amicable settlement would be reached if the recalcitrant son or daughter knows that the alternative is a public trial. It would be nice to think Singapore doesn"t need this kind of law. But that belief ignores the clear demographic trends and the effect of affluence itself on traditional bends. Those of us who pushed for the bill will consider ourselves most successful if it acts as an incentive not to have it invoked in the first place.