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单选题Current Group, a Germantown-based technology firm, has taken over an ordinary looking house in Bethesda and turned it into a laboratory for smart-grid technology, the system the company believes will bring the nation's electricity grids into the digital age. In the front yard stands a utility pole hooked up to a special transformer that connects the power lines to high-speed Internet. Hundreds of sensors attached to the lines monitor how power flows through the home. That information is then sent back to the utility company. The process lets a utility more efficiently manage the distribution of electricity by allowing two-way communication between consumers and energy suppliers via the broadband network on the power lines. Based on data they receive from hundreds of homes, utilities can monitor usage and adjust output and pricing in response to demand. Consumers can be rewarded with reduced rates by cutting back on consumption during peak periods. And computerized substations can talk to each other so overloaded circuits hand off electricity to those that have not fully loaded, helping to prevent blackouts. Some utility companies have launched initiatives to give consumers data about their energy consumption habits in an effort to lower energy bills. Smart-grid technology takes such programs further by automating electricity distribution, which would make grids more reliable and efficient. By partnering with utilities, the company hopes to tap into $4.5 billion in stimulus grants intended to encourage smart-grid development. When he announced the funding, President Obama pointed to a project in Boulder, Colo. , as an example of a successful smart-grid experiment. Current is one of the companies working on the project. Current's chief executive Tom Casey believes the technology will help utility companies better distribute electricity produced by renewable resources, such as solar panels or wind farms. " A smart grid's system can be paired up with the renewable resources so that when the renewable source is varying, the overall load can be varied as well, " Casey told the House Select Committee on Energy Independence and Global Warming. " This will reduce or eliminate the need for backup coal or gas-based power generation plants. /
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单选题Drug use is rising dramatically among the nation' s youth after a decade of decline. From 1993 to 1994, marijuana use among young people (1) from 12 to 17 jumped 50 percent. One in five high school seniors (2) marijuana daily. Monitoring the Future, which (3) student drug use annually, reports that negative attitudes about drugs have declined for the fourth year in a row. (4) young people see great risk in using drugs. Mood-altering pharmaceutical drugs are (5) new popularity among young people. Ritalin, (6) as a diet pill in the 1970s and now used to (7) hyperactive children, has become a (8) drug on college campuses. A central nervous system (9) , Ritalin can cause strokes, hypertension, and seizures. Rohypnol, produced in Europe as a (10) tranquilizer, lowers inhibitions and suppresses short-term memory, which has led to some women being raped by men they are going out with. (11) taken with alcohol, its effects are greatly (12) . Rock singer Kurt Cobain collapsed from an (13) of Rohypnol and champagne a month before he committed (14) in 1994. In Florida and Texas, Rohypnol has become widely abused among teens, who see the drug as a less expensive (15) for marijuana and LSD. Alcohol and tobacco use is increasing among teenagers, (16) younger adolescents. Each year, more than one million teens become regular smokers, (17) they cannot legally purchase tobacco. By 12th grade, one in three students smokes. In 1995, one in five 14-year-olds reported smoking regularly, a 33 percent jump (18) 1991. Drinking among 14-year-olds climbed 50 percent from 1992 to 1994,and all teens reported substantial increases in (19) drinking. In 1995, one in five 10th graders reported having been drunk in the past 30 days. Two-thirds of high school seniors say they know a (20) with a drinking problem.
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单选题Animal studies are under way, human trial protocols are taking shape and drug makers are on alert. All the international health community needs now is a human vaccine for the bird flu pandemic sweeping a cluster of Asian countries. The race for a vaccine began after the first human case emerged in Hong Kong in 1997. Backed by the World Health Organization (WHO), three research teams in the US and UK are trying to create a seed virus for a new vaccine. Their task is formidable, but researchers remain optimistic." There are obstacles, but most of the obstacles have been treated sensibly," says Richard Webby, a virologist at St. Jude Children's Research Hospital in Memphis, Tennessee. The biggest challenge is likely to be the rapidly mutating virus. Candidate vaccines produced last year against the H5N1 virus are ineffective against this year's strain. Scientists will have to constantly monitor the changes and try to tailor the vaccine as the virus mutates. They can't wait to see which one comes next. The urgency stems from fears that I-ISN1 will combine with a human flu virus, creating a pathogen(病原体) that could be transmitted from person to person. But if people have no immunity to the virus, the strain may not mutate as rapidly in people as it does in birds. To quickly generate the vaccine, researchers are using reverse genetics, which allows them to skip the long process of searching through reassorted viruses for the correct genetic combination. Instead, scientists clone sequences for hemagglutinin(红血球凝聚素) and neuraminidase(神经氨酸苷酶), the two key proteins in the virus. The sequences are then combined with human influenza genes to create a customized reference strain. Because products developed with reverse genetics have never been tested in humans, the candidate vaccines will first have to clear regulatory review. In anticipation, the US Food and Drug Administration (FDA) and the European Agency for the Evaluation of Medicinal Products (EMEA) are both preparing pandemic response plans. The EMEA has produced a fist-track licensing program, an industry task force and detailed guidance for potential applicants. In Europe, a reassortant influenza virus -- but not the inactivated vaccine -- produced by reverse genetics would be considered a genetically modified organism, and manufacturers would need approval from their national or local safety authorities. The WHO has prepared a preliminary biosafety risk assessment of pilot-lot vaccine, which could help speed up the review. A preliminary version of their protocol calls for several hundred subjects, beginning with a group of young adults and gradually expanding to include those most susceptible to the flu -- children and the elderly." If we had product," says Lambert," it would probably be a couple of months at the earliest before we have early data in healthy adults./
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单选题You know you should do it, other people do it all the time. Maybe you've already done it but it wasn't very satisfying, and you'd like to learn to do it better. I'm talking, of course, about having a business lunch. Don't feel embarrassed if you are uncomfortable with the idea of sitting over a grilled chicken breast, talking to a prospective client. Most inexperienced, overeager launchers believe the main purpose of a business lunch is to either (a) conduct business or (b) eat lunch, and they're unsure how to mix the two. Don't worry! Business lunches aren't about either business or lunch,they're about building relationships. One of my business rules is "People do business with people they like. " Often, it's not products, prices, or the company that makes the sale—it's the person Business lunches are the perfect time for you and your client, supplier, or employee to get to know each other as people. This helps establish common interests and makes working together easier. The single most important thing you can do at a business lunch—even more important than picking up the tab—is listen. You don't need a particular reason to ask someone to lunch, so don't wait until for a certain occasion or issue. Don't make it seem like lunch is going to be a sales call. Instead, try the straightforward approach, "We've been doing business together for almost a year. I'd like to take you to lunch and get to know you a little better." Or a little less straightforward, "I'm often in your area, how about having lunch sometime?" Have the other person suggest a place to eat—"Is there a restaurant you've been wanting to try?" Or if you have a limited budget, you choose a nice mid priced restaurant. Forget McDonald's. If you're thanking someone for an important order, take them to a really special, possibly new, restaurant. If you did the inviting, you pick up the tab, even if your guest says, "I can put this on my company's credit card." But don't have a scene arguing over the check. You can just say, "You can get the next one." Some companies have policies that don't permit employees to be treated; in that case, split the tab.
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