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单选题 In the 90's, people went crazy about wireless. Electronic communications once thought bound permanently to the world of cables and hard-wired connections suddenly were sprung free, and the possibilities seemed endless. Entrenched monopolies would fall, and a new uncabled era would usher in a level of intimate contact that would not only transform business but change human behavior. Such was the view by the end of that groundbreaking decade-the 1890s. To be sure, the wild publicity of those days wasn't all hot air. Marconi's "magic box" and its contemporaneous inventions kicked off an era of profound changes, not the least of which was the advent of broadcasting. So it does seem strange that a century later, the debate once more is about how wireless will change everything. And once again, the noisy confusion is justified. Changes are on the way that are arguably as earth shattering as the world's first wireless transformation. Certainly a huge part of this revolution comes from introducing the most powerful communication tools of our time. Between our mobile phones, our BlackBerries and Treos, and our Wi-Fi (Wireless Fidelity) computers, we're always on and always connected-and soon our cars and our appliances will be, too. While there has been considerable planning for how people will use these tools and how they'll pay for them, the wonderful reality is that, as with the Internet, much of the action in the wireless world will ultimately emerge from the imaginative twists and turns that are possible when digital technology trumps the analog mindset of telecom companies and government regulators. Wi-Fi is itself a shining example of how wireless innovation can shed the tethers of conventional wisdom. At one point, it was assumed that when people wanted to use wireless devices for things other than conversation, they'd have to rely on the painstakingly drawn, investment-heavy standards adopted by the giant corporations that earn a lot through your monthly phone bill. But then some researchers came up with a new communications standard exploiting an unlicensed part of the spectrum. It was called 802.11, and only later sexed up with the name Wi-Fi. Though the range of signal was only some dozens of meters, Wi-Fi turned out to be a great way to wirelessly extend an Internet connection in the home or office. A new class of activist was born: the bandwidth liberator, with a goal of extending free wireless internet to anyone venturing within the range of a free hotspot. Meanwhile, Apple Computer seized on the idea as a consumer solution, others followed and now Wi-Fi is as common as the modem once was.
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单选题Recalculating the global use of phosphorus, an important fertilizer element of modem agriculture, a team of researchers warns that the world's stocks may soon be in short supply and that overuse in the industrialized world has become a leading cause of the pollution of lakes, rivers and streams. Writing in the Feb. 14 edition of the journal Environmental Research Letters, Stephen Carpenter of the University of Wisconsin-Madison and Elena Bennett of McGill University report that the human use of phosphorus, primarily in the industrialized world, is causing the widespread eutrophication of fresh surface water. What's more, the minable global stocks of phosphorus are concentrated in just a few countries and are in decline, posing the risk of global shortages within the next 20 years. "There is a finite amount of phosphorus in the world," says Carpenter, one of the world's leading authorities on lakes and streams. "This is a material that's becoming rarer and we need to use it more efficiently." Phosphorus is an essential element for life. Living organisms, including humans, have small amounts and the element is crucial for driving the energetic processes of cells. In agriculture, phosphorus mined from ancient marine deposits is widely used to boost crop yields. The element also has other industrial uses. But excess phosphorus from fertilizer that washes from farm fields and suburban lawns into lakes and streams is the primary cause of the algae blooms that destroy freshwater ecosystems arid degrade water quality. Phosphorus pollution poses a risk to fish and other water life as well as to the animals and humans who depend on clean fresh water. In some instances, excess phosphorus sparks blooms of toxic algae, which pose a direct threat to human and animal life. "If you have too much phosphorus, you get eutrophication," explains Carpenter, of the cycle of excessive plant and algae growth that significantly degrades bodies of fresh water. "Phosphorus stimulates the growth of algae and weeds near shore and some of the algae can contain cyanobacteria, which are toxic. You lose fish. You lose water quality for drinking." The fertilizer-fueled algae blooms themselves amplify the problem as the algae die and release accumulated phosphorus back into the water. Complicating the problem, says Carpenter, is the fact that excess phosphorus in the environment is a problem primarily in the industrialized world, mainly Europe, North America and parts of Asia. In other parts of the world, notably Africa and Australia, soils are phosphorus poor, creating a stark imbalance. Ironically, soils in places like North America, where fertilizers with phosphorus are most commonly applied, are already loaded with the element. Bennett and Carpenter argue that agriculture practices to better conserve phosphate within agricultural ecosystems are necessary to avert the widespread pollution of surface waters. Phosphorus from parts of the world where the element is abundant, they say, can be moved to phosphorus deficient regions of the world by extracting phosphorus from manure, for example, using manure digesters. (490 words)
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单选题In which case will mother be serving "noodles" ?
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单选题{{B}}Part A{{/B}}{{B}}Directions:{{/B}}Read the following four texts. Answer the questions below each text by choosing A, B, C, or D. Mark your answers on ANSWER SHEET 1. {{B}}Text 1{{/B}} When, in the age of automation, man searches for a worker to do the tedious, unpleasant jobs that are more or less impossible to mechanize, he may very profitably consider the ape. If we tackled the problem of breeding for brains with as much enthusiasm as we devote to breeding dogs of surrealistic shapes, we could eventually produce assorted models of useful primates, ranging in size from the gorilla down to the baboon, each adapted to a special kind of work. It is not putting too much strain on the imagination to assume that geneticists could produce a super-ape, which is able to understand some scores of words and capable of being trained for such jobs as picking fruit, cleaning up the litter in parks, shining shoes, collecting garbage, doing household chores and even baby-sitting, although I have known some babies I would not care to trust with a valuable ape. Apes could do many jobs, such as cleaning streets and the more repetitive types of agricultural work, without supervision, though they might need protection from those egregious specimens of Home sapiens who think it amusing to tease or bully anything they consider lower on the evolutionary ladder. For other tasks, such as delivering papers and laboring on the docks, our man-ape would have to work under human overseers; and, incidentally, I would love to see the finale of the twenty-first century version of On the Waterfront in which the honest but hairy hero will drum on his chest after—literally—taking the wicked labor leader apart. Once a supply of nonhuman workers becomes available, a whole range of low IQ jobs could be thankfully given up by mankind, to its great mental and physical advantage. What is more, one of the problems which has annoyed so many fictional Utopias would be avoided: There would be none of the degradingly subhuman Epsilons of Huxley's Brave New World to act as a permanent reproach to society, for there is a profound moral difference between breeding sub-men and super-apes, though the end products are much the same. The first would introduce a form of slavery, but the second would be a biological triumph which could benefit both men and animals.{{B}}Notes:{{/B}} surrealistic 超现实的。primate 灵长类动物。 gorilla 大猩猩。 baboon 狒狒。chore 杂活。 care to do sth. (常用于否定句)( =willing to do or agree to do sth. ) 愿意做某事。trust A with B把B 托付给A. egregious (通常指坏人或坏事) 异乎寻常的,突出的。Home sapiens 人类。finale n. 结局。 Epsilons 奴隶人名。assorted 各色各样的。Utopia 乌托邦,理想主义。
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单选题Until about four decades ago, crop yields in agricultural systems depended on (1) resources, recycling organic matter, built-in biological control mechanisms and rainfall patterns. Agricultural yields were (2) but stable. Production was (3) by growing more than one crop or variety in space and time in a field as insurance against pest (4) or severe weather. Inputs of nitrogen were (5) by rotating major field crops with legumes. In turn, rotations suppressed insects, weeds and diseases by effectively (6) the life cycles of these pests. A typical corn belt farmer grew corn (7) with several crops including soybeans, and small grain production was intrinsic to maintain livestock. Most of the labor was done by the family with occasional hired help and no (8) equipment or services were purchased from off4arm sources. In these type of farming systems the link between agriculture and ecology was quite (9) and signs of environment degradation were seldom evident. But as agriculture modernization (10) the ecology-farming linkage was often broken as ecological principles were (11) . In fact, several agricultural scientists have arrived at a (12) consensus that modem agriculture confronts an environment crisis. A growing number of people have become concerned about the long-term (13) of existing food production systems. Evidence has shown that (14) the present capital-and-technology-intensive fanning systems have been extremely productive and competitive, they also bring a (15) of economic, environmental and social problems. Evidence also shows that the very nature of the agricultural structure and prevailing polices have led to this environmental (16) by favoring large farm size, specialized production, crop monocultures and mechanization. Today as more and more farmers are integrated (17) international economies, imperatives to (18) disappear and monocultures are rewarded by economies of scale. In turn, lack of rotations and diversification (19) key self-regulating mechanisms, turning monocultures into highly (20) agro-ecosystems dependent on high chemical inputs.
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单选题{{B}}Text 4{{/B}} Artificial hearts have long been the stuff of science fiction. In "Robocop", snazzy cardiac devices are made by Yamaha and Jensen, and in "Star Trek", Jean-Luc Picard, captain of the Enterprise, has one implanted in the year 2328. In the present day, however, their history has been more chequered. The first serious attempt to build one happened in the 1980s, when Jarvik-7, made by Robert Jarvik, a surgeon at the University of Utah, captured the world's attention. But Jarvik-7 was a complicated affair that needed to be connected' via tubes to machines outside the body. The patient could not go home, nor even turn around in bed. Various other designs have been tried since, but all were seen as temporary expedients intended to tide a patient over until the real thing became available from a human donor. That may be about to change. This week, America's Food and Drug Administration gave its approval to a new type of artificial heart made by Abiomed, a firm based near Boston. The agency granted a "humanitarian device exemption", a restricted form of approval that will allow doctors to implant the new device in people whose hearts are about to fail but who cannot, for reasons such as intolerance of the immunosuppressive drugs needed to stop rejection, receive a transplant. Such people have a life expectancy of less than a month, but a dozen similarly hopeless patients implanted with Abiomed's heart survived for about five months. Unlike Dr. Jarvik's device, this newfangled bundle of titanium and polyurethane alms to set the patient free. An electric motor revolving up to 10 000 times a minute pushes an incompressible fluid around the Abiomed heart, and that fluid, in turn, pushes the blood--first to the lungs to be oxygenated, and then around the body. Power is supplied by an electric current generated in a pack outside the body. This induces current in the motor inside the heart. All diagnostics are done remotely, using radio signals. There are no tubes or wires coming out of the patient. The charger is usually plugged into the mains, but if armed with a battery it can be carried around for hours in a vest or backpack, thus allowing the patient to roam freely. Most strikingly, the device's internal battery can last half an hour before it needs recharging. That allows someone time to take a shower or even go for a quick swim without having to wear the charger. Abiomed's chairman, Michael Minogue, does not claim that his firm's product will displace human transplants. Even so, the firm has big ambitions. It is already developing a new version that will be 30% smaller (meaning more women can use it) and will last for five years. That should be ready by 2008--320 years earlier than the writers of "Star Trek" predicted.
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单选题 Manufacturers of everything from running shoes to deodorants, a substance to remove unpleasant odors, design products specifically for women. One of the latest entries: the first artificial joint created for-and heavily advertised to-females. Doctors say it's too soon to tell whether the Gender Knee represents a giant leap for womankind or if it gives its maker, Zimmer Holdings Inc., a leg up in the market. In the case of the knees, according to Zimmer, here's how men and women are different: First, the kneecap, is thinner in women. Also, women's wider hips create a different angle between the knee and pelvis-the wide, curved group of bones at the level of hips, which can mean the kneecap gets pulled to the side when the muscles contract. And the end of the thighbone is typically narrower in men. Most artificial knees were modeled on the male anatomy-which may explain why knee replacements in women aren't as successful when measured by reported pain and do-over rates. But will the new (and more expensive) replacement actually serve women better? "In theory, yes, but the evidence isn't there," says Kimberly Templeton, an associate professor of orthopedic surgery (prevention or correction of disorders of the bones and associated muscles and joints) at the University of Kansas Medical Center and a spokesperson for the American Academy of Orthopedic Surgeons. Sheryl Conley, Zimmer's chief marketing officer, says seven studies now underway will look at patient satisfaction and range of motion. Preliminary data will be available in a year or so. Anatomical differences aside, Templeton says, replacement knees may not perform well in women in part because females tend to delay surgery-sometimes until they're bound to the house by disability. In addition, it's not clear that the manufacturer's specialized design will translate to less pain, says Steven Haas, an orthopedic surgeon and chief of the knee service at the Hospital for Special Surgery in New York. For example, making the front of the replacement knee thinner by one twenty-fifth of an inch won't necessarily make a noticeable difference to recipients. Having a correctly fitted device is clearly important, says Haas, who notes that other companies have modified their smaller knees to account for gender differences in anatomy. (Haas has consulted with Smith & Nephew, a rival to Zimmer.) More important, says Haas, is to find a skillful surgeon. Differences between implants, he argues, are relatively minor compared to the technique of the surgeon putting them in.
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单选题{{B}}Text 3{{/B}} Something big is happening to the human race--something that could be called The Great Transformation. The Transformation consists of all the changes that are occurring m human life due to advancing technology. For thousands of years such progress occurred slowly. Now, everything is changing so fast that you may find yourself wondering where all this progress is really leading. Nobody knows what all these changes really will mean in the long run. But this mysterious Transformation is the biggest story of all time. It is the story of the human race itself. Some people worry about what will happen when the deposits of petroleum are gone, but already researchers are finding all kinds of new ways to obtain energy. Someday, solar power collected by satellites circling the earth of fission power manufactured by mankind may give us all the energy we need for an expanding civilization. Space exploration promises to open up many new territories for human settlement, as well as leading to the harvest of mineral resources like the asteroids. Scientific research continues to open up previously undreamed-of possibilities. Fifty years ago, few people could even imagine things like computers, lasers, and holography. Today, a host of newly emerging technologies such as artificial intelligence and genetic engineering are opening up all kinds of new paths for technologists. Like it or not, our advancing technology has made us masters of the earth. We not only dominate all the other animals, but we are reshaping the world' s plant life and even its soil and rocks, its waters and surrounding air. Mountains are being dug up to provide minerals and stone for buildings. The very ground under our feet is washing away as we chop down the forests, plow up the fields, and excavate foundations for our buildings. Human junk is cluttering up not only the land but even the bottom of the sea. And so many chemicals are being released into the air by human activities that scientists worry that the entire globe may warm, causing the polar icecaps to melt and ocean waters to flood vast areas of the land. During the twentieth century, advancing technology has enabled man to reach thousands of feet into the ocean depths and to climb the highest mountains. Mount Everest, the highest mountain of all, resisted all climbers until the 1950's: Now man is reaching beyond Earth to the moon, Mars, and the stars. No one knows what the Great Transformation means or where it will ultimately lead. But one thing is sure: Human life 50 years from now will be very different from what it is today. It's also worth noting that our wondrous technology is posing an increasingly insistent question: When we can do so many things, how can we possibly decide what we really should do? When humans were relatively powerless, they didn't have to make the choices they have to make today. Technology gives us the power to build a magnificent new civilization—if we can just agree on what we want it to be. But today, there is little global agreement on goals and how we should achieve them. So it remains to be seen what will happen as a result of our technology. Pessimists worry that we will use the technology eventually to blow ourselves up. But they have been saying that for decades, and so far we have escaped. Whether we will continue to do so remains unknown--but we can continue to hope.
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单选题From the text, we can see that the writer's overall attitude towards the issue seems to be ______.
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单选题Some children are backward in speaking probably because ______.
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单选题It can be inferred from the second paragraph that the consumers used to be put at a disadvantage in a large part due to
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单选题The mid-sixties saw the start of a project that, along with other similar research, was to teach us a great deal about the chimpanzee mind. This was Project Washoe, conceived by Trixie and Allen Gardner. They purchased an infant chimpanzee and began to teach her the signs of ASL, the American Sign Language used by the deaf. Twenty years earlier another husband and wife team, Richard and Cathy Hayes, had tried, with an almost total lack of success, to teach a young chimp, Vikki, to talk. The Hayes*s undertaking taught us a lot about the chimpanzee mind, but Vikki, although she did well in IQ tests, and was clearly an intelligent youngster, could not learn human speech. The Gardners, however, achieved spectacular success with their pupil, Washoe. Not only did she learn signs easily, but she quickly began to string them together in meaningful ways. It was clear that each sign evoked, in her mind, a mental image of the object it represented. If, for example, she was asked, in sign language, to fetch an apple, she would go and locate an apple that was out of sight in another room. Other chimps entered the project, some starting their lives in deaf signing families before joining Washoe. And finally Washoe adopted an infant, Loulis. He came from a lab where no thought of teaching signs had ever penetrated. When he was with Washoe he was given no lessons in language acquisition—not by humans, anyway. Yet by the time he was eight years old he had made fifty-eight signs in their correct contexts. How did he learn them? Mostly, it seems, by imitating the behavior of Washoe and the other three signing chimps, Dar, Moja and Tam. Sometimes, though, he received tuition from Washoe herself. One day, for example, she began to swagger about bipedally, hair bristling, signing food! food! food! in great excitement. She had seen a human approaching with a bar of chocolate. Loulis, only eighteen months old, watched passively. Suddenly Washoe stopped her swaggering, went over to him, took his hand, and moulded the sign for food (fingers pointing towards mouth). Another time, in a similar context,, she made the sign for chewing gum—but with her hand on his body. On a third occasion Washoe picked up a small chair, took it over to Loulis, set it down in front of him, and very distinctly made the chair sign three times, watching him closely as she did so. The two food signs became incorporated into Loulis's vocabulary but the sign for chair did not. Obviously the priorities of a young chimp are similar to those of a human child! Chimpanzees who have been taught a language can combine signs creatively in order to describe objects for which they have no symbol. Washoe, for example, puzzled her caretakers by asking, repeatedly, for a rock berry. Eventually it transpired that she was referring to brazil nuts which she had encountered for the first time a while before. Another language-trained chimp described a cucumber as a green banana. They can even invent signs. Lucy, as she got older, had to be put on a leash for her outings. One day, eager to set off but having no sign for leash, she signaled her wishes by holding a crooked index finger to the ring on her collar. This sign became part of her vocabulary.
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