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第三篇 Clone Farm Factory farming could soon enter a new era of mass production. Companies in the US are developing the technology needed to "clone" chickens on a massive scale. Once a chicken with desirable traits has been bred or genetically engineered, tens of thousands of eggs, which will hatch into identical copies, could roll off the production lines every hour. Billions of clones could be produced each year to supply chicken farms with birds that all grow at the same rate, have the same amount of meat and taste the same. This, at least, is the vision of the US’s National Institute of Science and Technology, which has given Origen Therapeutics of Burlingame, California, and Embrex of North Carolina $4.7 million to help fund research. The prospect has alarmed animal welfare groups, who fear it could increase the suffering of farm birds. That’s unlikely to put off the poultry industry, however, which wants disease-resistant birds that grow faster on less food. "Producers would like the same meat quantity but to use reduced inputs to get there," says Mike Fitzgerald of Origen. To meet this demand, Origen aims to "create an animal that is effectively a clone", he says. Normal cloning doesn’t work in birds because eggs can’t be removed and implanted. Instead, the company is trying to bulk-grow embryonic stem cells taken from fertilized eggs as soon as they’re laid, "The trick is to culture the cells without them starting to distinguish, so they remain pluripotent," says Fitzgerald. Using a long-established technique, these donor cells will then be injected into the embryo of a freshly laid, fertilized recipient egg, forming a chick that is. a "chimera". Strictly speaking a chimera isn’t a clone, because it contains cells from both donor and recipient. But Fitzgerald says it will be enough if, say, 95 percent of a chicken’s body develops from donor cells. "In the poultry world, it doesn’t matter if it’s not 100 percent," he says. Another challenge for Origen is to scale up production. To do this, it has teamed up with Embrex, which produces machines that can inject vaccines into up to 50,000 eggs an hour. Embrex is now trying to modify the machines to locate the embryo and inject the cells into precisely the right spot without killing it. In future, Origen imagines freezing stem cells from different strains of chicken. If orders come in for a particular strain, millions of eggs could be produced in months or even weeks. At present, maintaining all the varieties the market might call for is too expensive for breeders, and it takes years to breed enough chickens to produce the billions of eggs that farmers need. Which of the following statements about Origen and Embrex is correct according to the fifth paragraph
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阅读下面这篇短文，短文后列出了7个句子，请根据短文的内容对每个句子作出判断。如果该句提供的是正确信息，请选择A项；如果该句提供的是错误信息，请选择B项；如果该句信息文章中没有提及，请选择C项。 Easy Learning Students should be jealous. Not only do babies get to doze their days away, but they’ve also mastered the fine art of learning in their sleep. By the time babies are a year old they can recognise a lot of sounds and even simple words. Marie Cheour at the University of Turku in Finland suspected that they might progress this fast because they learn language while they sleep as well as when they are awake. To test the theory, Cheour and her colleagues studied 45 newborn babies in the first few days of their lives. They exposed all the infants to an hour of Finnish vowel sounds — one that sounds like "oo", another like "ee" and a third boundary vowel peculiar to Finnish and similar languages that sounds like something in between. EEG recordings of the infants brains before and after the session showed that the newborns could not distinguish the sounds. Fifteen of the babies then went back with their mothers, while the rest were split into two sleep-study groups. One group was exposed throughout their night-time sleeping hours to the same three vowels, while the others listened to other, easier-to-distinguish vowel sounds. When tested in the morning, and again in the evening, the babies who’d heard the tricky boundary vowel all night showed brainwave activity indicating that they could now recognise this new sound. They could identify the sound even when its pitch was changed, while none of the other babies could pick up the boundary vowel at all. Cheour doesn’t know how babies accomplish this night-time learning, but she suspects that the special ability might indicate that unlike adults, babies don’t "turn off" their cerebral cortex while they sleep. The skill probably fades in the course of the first year of life, she adds — so forget the idea that you can pick up tricky French vowels as an adult just by slipping a language tape under your pillow. But while it may not help grown-ups, Cheour is hoping to use the sleeping hours to give remedial help to babies who are genetically at risk of language disorders. Babies can learn language even in their sleep.
阅读下面的短文，文中有15处空白，每处空白给出了4个选项，请根据短文的内容从4个选项中选择1个最佳答案。 An Early Form of Jazz Music Music comes in many forms; most countries have a style of their own. At the turn of the last century, (51) jazz was born, America had no prominent. (52) of its own. No one knows exactly when it was invented or by whom. But it began to be (53) in the early 1890s. Jazz is America’s contribution to (54) music. In contrast to classical music, which (55) formal European traditions, jazz is spontaneous and free in form. It bubbles with energy, (56) the moods, interests, and emotions of the people. In the 1920s jazz (57) like America. And so it does today. The (58) of the music are as interesting as the music itself. American Negroes, or blacks, as they are called today, were the jazz pioneers. They were brought to the Southern states (59) slaves. They were sold to plantation owners and forced to work long hours. When a Negro died his friends and relatives (60) a procession to carry the body to the cemetery. In New Orleans, a band often accompanied the (61) . On the way to the cemetery the band played slow, solemn music suited to the occasion. (62) on the way home the mood changed. Spirits lifted. Death had removed one of their number, but the living were glad to be (63) . The band played (64) music, improvising on both the harmony and the melody of the tunes (65) at the funeral. This music made everyone want to dance. It was an early form of jazz.
So what is depression Depression is often more about anger turned (1) than it is about sadness. But it’s usually (2) as sadness. Depression can (3) at all ages, from childhood to old age, and it’s the United States’ No. 1 (4) problem.When someone is depressed, her behavior (5) change and she loses interest in activities she (6) enjoyed (like sports, music, friendships). The sadness usually lasts every day for most of the day and for two weeks or more.What (7) depression A (8) event can certainly bring (9) depression, but some will say it happens (10) a specific cause. So how do you know if you’re just having a bad day (11) are really depressed Depression affects your (12) , moods, behavior and even your physical health. These changes often go (13) or are labeled (14) simply a bad case of the blues.Someone who’s truly (15) depression will have (16) periods of crying spells, feelings of (17) (like not being able to change your situation) and (18) (tike you’ll feel this way forever), irritation or agitation. A depressed person often (19) from others, Depression seldom goes away by itself, and the greatest (20) of depression is suicide. The risk of suicide increases if the depression isn’t treated. 4（）
India has about a billion people and a dozen major languages of its own. One language, and only one, is understood-by the elite- across the country: that of the foreigners who ruled India for less than 200 years and left 52 years ago.Today, India. Tomorrow, unofficially, the world. That is well under way; at first, because the British not only built global empire but also it was settled by America, and now because the world (and notably America) has acquired its first truly global--and interactive--medium, the Internet.It is estimated that some 350 million people speak English as their first language. Maybe 250 - 350 million do or can use it as a second language; in excolonial countries, notably, or in English--majority ones, like 30 million recently immigrants to the United States, or Canada’s 6 million francophone Quebeckers. And elsewhere.’ The guess is 100 million--1 billion depending how you define "can". Let us be hold: in all, 20 -25% of earth’ s 6 billion people can use English; not the English of England, let alone of Dr. Johnson, but English.That number is soaring as each year brings new pupils to school and carries of monolingual oldies--and now as the Internet spreads. And the process is self-reinforcing. As business spreads across frontiers, the company that wants to move its executives around, and to promote the best of them, regardless of nationality, encourages the uses of English. So the executive who wants to be in the frame, or’ to move to another employer, learns to use it. English has long dominated learned journals: German, Russian or French (depending on the field) may be useful to their expert readers, but English is essential. So, if you want your own work published--and widely read by your peers--then English is the language of choice.The growth of the cinema, and still more so of television, has spread the dominant language. Foreign movies or sitcoms may be dubbed into major languages, but for smaller audiences they are usually subtitled. Result: a Dutch or Danish or even Arab family has an audio-visual learning aid in its living-room, and usually the language spoken on-screen is English.The birth of the computer and its American operating systems gave English a nudge ahead: that of the Internet has given it a huge push. Any web-linked household today has a library of information available at the click of a mouse. And, unlike the books on its own shelves or in the public library, maybe four-fifths is written in English. That proportion may lessen, as more non-English sites spring up. But English will surely dominate. Which of the following is NOT mentioned when the author explains the reasons of the rapid growing number of English speaker（）
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