单选题What do the writer think about his or her children?

单选题Mark Twain once observed that giving up smoking is easy. He knew, because he' d done it hundreds of times himself. Giving up for ever is a trifle more difficult, apparently, and it is well known that it is much more difficult for some people than for others. Why is this so? Few doctors believe any longer that it is simply a question of will power. And for those people that continue to view addicts as merely "weak", recent genetic research may force a rethink. A study conducted by Jacqueline Vink, of the Free University of Amsterdam, used a database called the Netherlands Twin Register to analyze the smoking habits of twins. Her results, published in the Pharmacogenomics Journal, suggest that an individual's degree of nicotine dependence, and even the number of cigarettes he smokes per day, are strongly genetically influenced. The Netherlands Twin Register is a voluntary database that contains details of some 7,000 pairs of adult twins (aged between 15 and 70) and 28,000 pairs of childhood twins. Such databases are prized by geneticists because they allow the comparison of identical twins (who share all their genes) with fraternal twins (who share half). In this case, however, Dr. Vink did not make use of that fact. For her, the database was merely a convenient repository of information. Instead of comparing identical and fraternal twins, she concentrated on the adult fraternal twins, most of whom had completed questionnaires about their habits, including smoking, and 536 of whom had given DNA samples to the register. The human genome is huge. It consists of billions of DNA "letters", some of which can be strung together to make sense (the genes) but many of which have either no function, or an unknown function. To follow what is going on, geneticists rely on markers they have identified within the genome. These are places where the genetic letters may vary between individuals. If a particular variant is routinely associated with a particular physical feature or a behavior pattern, it suggests that a particular version of a nearby gene is influencing that feature or behavior. Dr. Vink found four markers which seemed to be associated with smoking. They were on chromosomes 3, 0, 10 and 14, suggesting that at least four genes are involved. Dr. Vink hopes that finding genes responsible for nicotine dependence will make it possible to identify the causes of such dependence. That will help to classify smokers better (some are social smokers while others are physically addicted) and thus enable "quitting" programs to be customized. Results such as Dr. Vink's must be interpreted with care. Association studies, as such projects are known, have a disturbing habit of disappearing, as it were, in a puff of smoke when someone tries to replicate them. But if Dr. Vink really has exposed a genetic link with addiction, then Mark Twain's problem may eventually become a thing of the past.

单选题{{B}}Text 2{{/B}} The day of terror at the Virginia Polytechnic and State University in Blacksburg began at about 7:15 a. m. , with the shooting of a woman and a male resident adviser on the fourth floor of a dorm building on campus, Kristen Bensley, a freshman who lived below the floor where the shooting occurred, told TIME, "There were minors going on about the assailant was fighting with his girlfriend or something of that nature." Bensley notes that only residents can get into the building, using a specific "passport", that is, a card that one has to swipe in order to open doors before 10 a.m. If he was an outsider, someone would have had to let him in. Or more likely, he was a resident of the dorm himself. If so, how did be keep so much ammunition unnoticed? Unlike high schools, most universities can't beef up security with a metal detector or two. So what can be done to protect students? Other questions remain unanswered. Why was there a two-hour gap between the incident at the dorm and a far more fatal one across campus? At one point, that led to theorizing that more than one gunman was involved. The gunman who killed at least 30 people at Norris Hall shortly after 9 a.m. was described by some sources as an Asian man. It has been a surreal time for the students. Brandon Stiltner, a senior aerospace engineering student, and Jonathan Hess, a senior mechanical engineer, were watching TV all day but by noon they'd had enough. "We decided we needed to do something," Stiltner said. "We were worthless sitting around." So they took their six-foot Virginia Tech sign off the wall and logged into Facebook. Within the next few hours 100 people replied to their e-mail request for a vigil. By 8 p.m. hundreds bf students began filing down the steps of the War Memorial Chapel toward the drill field. Clusters of two and three students stood together in silence. Slowly they began to line up to sign the board. "I'm still really in disbelief," says Stiltner. The shock of the day's shootings sank in, Hess said, as he carried the sign across campus for the vigil. "It hit me," Hess said, "to know that it was in these buildings." The media crews that swarmed campus were also surreal to Hess and Stiltner. "We could look out our window and see exactly what's on TV," Stiltner says. He watched his sign crowded with initials and prayers, awaiting the names of the victims, He shuddered. "I hope I don't have any nasty surprises."

单选题Trying to get Americans to eat a healthy diet is a frustrating business. Even the best-designed public-health campaigns cannot seem to compete with the tempting flavors of the snack-food and fast-food industries and their fat-and sugar-laden products. The results are apparent on a walk down any American street—more than 60% of Americans are overweight, and a full quarter of them are overweight to the point of obesity. Now, health advocates say, an ill-conceived redesign has taken one of the more successful public-health campaigns—the Food Guide Pyramid—and rendered it confusing to the point of uselessness. Some of these critics worry that America's Department of Agriculture caved in to pressure from parts of the food industry anxious to protect their products. The Food Guide Pyramid was a graphic which emphasizes that a healthy diet is built on a base of grains, vegetables and fruits, followed by ever-decreasing amounts of dairy products. meat, sweets and oils. The agriculture department launched the pyramid in 1992 to replace its previous program, which was centered on the idea of four basic food groups. The "Basic Four" campaign showed a plate divided into quarters, and seemed to imply that meat and dairy products should make up half of a healthy diet, with grains, fruits and vegetables making up the other half. It was replaced only over the strenuous objections of the meat and dairy industries. The old pyramid was undoubtedly imperfect. It failed to distinguish between a doughnut and a whole-grain roll, or a hamburger and a skinless chicken breast, and it did not make clear exactly how much of each foodstuff to eat. It did, however, manage to convey the basic idea of proper proportions in an easily understanable way. The new pyramid, called" My Pyramid", abandons the effort to provide this information. Instead, it has been simplified to a mere logo. The food groups are replaced with unlabelled, multi-colored vertical stripes which, in some versions, rise out of a cartoon jumble of foods that look like the aftermath of a riot at a grocery store. Anyone who wants to see how this translates into a healthy diet is invited to go to a website, put in their age, Sex and activity level, and get a Custom. designed pyramid, complete with healthy food choices and suggested portion sizes. This is fine for those who are motivated, but might prove too much effort for those who most need such information. Admittedly, the designers of the new pyramid had a tough job to do. They were supposed to condense the advice in the 84-page United States' Dietary Guidelines into a simple, meaningful graphic suitable for printing on the back of a cereal box. And they had to do this in the face of pressure from dozens of special interest groups—from the country's Potato, Board, which thought potatoes would look nice in the picture, to the Almond Board of California, which felt the same way about almonds. Even the National Watermelon Promotion Board and the California Avocado Commission were eager to sect heir products recognized. Nevertheless, many health advocates believe the new graphic is a missed opportunity. Although officials insist industry pressure had nothing to do with: the eventual design, some critics suspect that political influence was at work: On the other hand, it is not clear how much good even the best graphic could do. Surveys found that 80% of Americans recognized the old Food Guide Pyramid—a big success in the world of public, health campaigns. Yet only 16% followed its advice.

单选题What can we infer from the fact that the world was perceived as flat?

单选题Ethics was generally considered to be

单选题The implication of the second paragraph is that Abraham Lincoln______

单选题Which of the following example's tells us that the animals also have a kind of culture difference

单选题What's your earliest childhood memory? Can you remember learning to walk? Or talk? The first time you (1) thunder or watched a television program? Adults seldom (2) events much earlier than the year or so before entering school, just as children younger than three or four (3) retain any specific, personal experiences. A variety of explanations have been (4) by psychologists for this "childhood amnesia". One argues that the hippocampus, the region of the brain which is responsible for forming memories, does not mature (5) about the age of two. But the most popular theory (6) that, since adults do not think like children, they cannot (7) childhood memories. Adults think in words, and their life memories are like stories or (8) —one event follows (9) —as in a novel or film. But when they search through their mental (10) for early childhood memories to add to this verbal life story, they don't find any that fits the (11) . It's like trying to find a Chinese word in an English dictionary. Now psychologist Annette Simms of the New York State University offers a new (12) for childhood amnesia. She argues that there simply (13) any early childhood memories to recall. According to Dr. Simms, children need to learn to use (14) spoken description of their personal experiences in order to turn their own short-term, quickly (15) impressions of them into long-term memories. In other (16) , children have to talk about their experiences and hear others talk about (17) —Mother talking about the afternoon (18) looking for seashells at the beach or Dad asking them about their day at Ocean park. Without this (19) reinforcement, says Dr. Simms, children cannot form (20) memories of their personal experiences.

单选题Which of the following best describes why the restrictive banking taws of the 1930' s are still on the book?

单选题It can be inferred from the third paragraph that the author's attitude toward the reduction of the international payments deficit seems

单选题In October 2002, Goldman Sachs and Deutsche Bank (1) a new electronic market (www.gs.com/econderivs/) for economic indices that (2) substantial economic risks, such as nonfarm payroll ( a measure of job availability) and retail sales. This new market was made possible by a (3) rating technology, developed by Longitude, a New York company providing software for financial markets, (4) the Parimutuel Digital Call Auction. This is "digital" (5) of a digital option : ie, it pays out only if an underlying index lies in a narrow, discrete range. In effect, Longitude has created a horse race, where each "horse" wins if and (6) the specified index falls in a specified range. By creating horses for every possible (7) of the index, and allowing people to bet (8) any number of runners, the company has produced a liquid integrated electronic market for a wide array of options on economic indices. Ten years ago it was (9) impossible to make use of electronic information about home values. Now, mortgage lenders have online automated valuation models that allow them to estimate values and to (10) the risk in their portfolios. This has led to a proliferation of types of home loan, some of (11) have improved risk-management characteristics. We are also beginning to see new kinds of (12) for homes, which will make it possible to protect the value of (13) ,for most people, is the single most important (14) of their wealth. The Yale University-Neighbourhood Reinvestment Corporation programme, (15) last year in the city of Syracuse, in New York state, may be a model for home-equity insurance policies that (16) sophisticated economic indices of house prices to define the (17) of the policy. Electronic futures markets that are based on econometric indices of house prices by city, already begun by City Index and IG Index in Britain and now (18) developed in the United States, will enable home-equity insurers to hedge the risks that they acquire by writing these policies. These examples are not impressive successes yet. But they (19) as early precursors of a technology that should one day help us to deal with the massive risks of inequality that (20) will beset us in coming years.

单选题 Hope may be the lovely, lyrical, inspiring thing many people believe it is-"the thing with feathers," as Emily Dickinson called it. But to scientists, it's also a more dull thing as well: a skill, a tool, a simple choice that is a lot less accidental or lucky. As psychologist Shane Lopez, a senior scientist at the Gallup organization argues in his new book, Making Hope Happen, it's also much more attainable than it seems. In both children and adults, there can be a hard-to-deny link between a robust sense of hope and either work productivity or academic achievement. In studies of this idea, hope is measured by a widely accepted psychological survey and productivity is measured by grades earned, sales made, widgets manufactured etc.. When Lopez and his colleagues recently gathered up a large body of this research and subjected it all to a meta-analysis, they came up with what they believe are very solid numbers: "Our finding was that hope accounts for about 14% of work productivity and 12% of academic achievement. " Hoping, Lopez stresses, is a lot different from wishing, though the two are often mixed. The super- bestseller The Secret is based on the vaguely defined and not-exactly peer-reviewed "law of attraction," which in this case means that just having positive thoughts about wealth, love, success and more can draw all of those things to you. "This wonderful future will happen for you if you just sit back and wish hard enough," Lopez says. But wishing, he explains is only an element of hope-it is, in a sense, hope without a plan. And that often leads nowhere. Effective hoping, Lopez says, is a very deliberate, three-step process. First there is selecting a goal, whether short-term or long term. Then you have to consider the gap between where you are now and where you will be when you achieve the goal, and lay out a series of sequential, short-term goals that will allow you to close that gap. Finally, there is the execution, establishing a plan for when you will begin to implement those steps and where and how you will execute them. It's far too much to say that effective hoping is the only—or even the biggest—part of what it takes to succeed. If 14% of business productivity can be attributed to hope, which means 86% is dependent on raw talent, capricious business cycles, the quality of the product you're selling, and often pure luck. But even if hope is just one ingredient in all of that, it's a catalyzing, energizing one-the gas in the tank, the fuel rod in the reactor, the Mentos in the Pepsi. Hope may be the thing with feathers-but it's also the thing with power.