A team led by Professor Theoder Berger, from the University of Southern California, can now manipulate brain cells in rats so that memories stored in the hippocampus, a brain area crucial for memory formation, are activated or suppressed . It's said that _ could one day have medical applications. In the study, researcher first trained rats to remember which of two levers they pressed first, then to press the other lever. As the rats performed the task, the scientists carefully monitored the electrical activity in each creature's hippocampus to find the pattern of nerve-cell activity involved in making a solid memory. Using the same glass needles they had used to record the nerve activity, they stimulated nerves in the same pattern and found that the animals' performance in the task got even better. The rats made fewer errors and were able to remember which lever was the"correct"one for a longer period of time. The scientists went a step further and suppressed the rats' memories with a drug called Mk801, which caused them to forget their task. When the animals' brain cells were later stimulated with the"correct"pattern, they remembered again which lever to press. "What's really exciting about this study is that when they played back the'good' patterns--the patterns when the animal got the task right--it did appear to improve memory,"said Dean Buonomano, an associate professor at the University of California. The final goal, Berger said, is to help people with stroke and epilepsy and the like strengthen memories and to help doctors treat them. The technology might even help sufferers of post-traumatic stress disorder. But first, researchers would have to show that they can stimulate or suppress far more complex memories than the ones in the rat experiment. "Here ,it's a simple task,"Buonomano said. In contrast, humans' memories are very rich and specific... "We have very many steps to go before this can be achieved,"he said. What can we infer from the article? A) MK801 is a drug that can be used to stimulate nerves. B) The study is expected to be used to help stroke and epilepsy patients recover completely. C) Using the study to improve humans' memories still face many challenges. D) Researchers have studied far more complex memories than the ones in the rat experiment.
C
(Question)
For the most part, schools are designed to produce people who fit into society, not people who set out to change it. However, schools, particularly universities, may not only spread culture; they may add to the cultural heritage. Today American society places a good deal of emphasis on the development of new knowledge, especially in the physical and biological sciences, medicine, and engineering. In recent years, the nation's leading universities have increasingly become research centres. An emphasis on research has led universities to judge professors not by abilities as teachers, but as researchers. Promotions, salary increases, and other benefits have long been dependent on research and publication. However, the most important is no longer publishing. To be successful these days, professors have to bring in money provided by government and private industry. Critics claim that academic success is most likely to come to those who have learned to "ignore" their teaching duties to pursue research activities. Defenders say that even when students themselves are not involved in research projects they benefit from such an emphasis on research. Major research universities like the Massachusetts Institute of Technology have also cooperated with industrial companies to develop technology and products with commercial potential. With university-industry ties continuing to grow, debate has increased about the consequences for basic science, academic openness, the control of information, the direction of research, and the influence on students. The author seems to be _ the move of emphasis to research. A) totally against B) sorry to see C) in favor of D) neutral about
(Answer)
D
Ques: It's 8:30, time for John to start work. So he turns on his radio. Then he eats breakfast. As he eats, he reads his e-mail and reviews his to-do list. Then he sits on the sofa and thinks about an article he needs to write ... Wait a minute! Radio? Breakfast? Sofa? What kind of workplace is this? Well, actually it is John's house, and he is a telecommuter -- he works at home, communicating with the workplace through the Internet. Like John, millions of people -- and their employers -- are finding that telecommuting is a great way to work. Telecommuters can follow their own timetables. They work in the comfort of homes, where they can also look after young children or elderly parents. They save time and money by not traveling to work. Their employers save, too, because they need less office space and furniture. Studies show that telecommuters change jobs less often. This saves employers even more money. Telecommuting helps society, too, by reducing pollution and traffic problems. Jobs that are _ telecommuting include writing, design work, computer programming and accounting. If a job is related to working with information, a telecommuter can probably do it. One of the advantages of telecommuting is that you can _ . A) work for several employers B) enjoy a lot of traveling C) get along well with other workers D) work on your own schedule
Ans: D
Question: In Yemen, you always see one type of vehicle on the road: the water truck.They travel mountain roads and cross deserts to bring Yemenis the goods more valuable than oil.It is one that only the rich can afford, with the supply regularly being cut off.Others must rely on scarce rain or charity to fight thirst. Experts say Yemen is going to be the first country in the world to run out of water.The capital, Sanaa, will run out of drinking water as early as 2025,says a report by the World Bank. Hannan, an 18yearold from Lahej, said that only the rich could prepare for cuts in supply."In a good week we'll have a water supply all week but then the following week there will be water only for a day or two, " she said. She and her husband, a factory worker, pay 3,000 riyals (99yuan) for a week's supply of water from a touring water truck when the taps run dry.With an income of only 20,000 riyals (660yuan) a month,this means the family often spend half their money on water. "There are a lot of people who can't afford it and they have to rely on their neighbors to help," she said. The average person in Yemen survives on onefifth of what the World Health Organization considers to be enough water. In Taiz, in the south,tap water is available only once every 45 days.In the mountainous Malhan district in the north,women and children climb a 1,500m mountain to collect water from a spring, often in the small hours to avoid long queues. Yemen is located in Southwest Asia,bordering the Arabian and Red Sea.Yemeni people have lived on scarce water supplies for thousands of years but that problem has been made serious by conflict in the area,the fastgrowing population and the use of water to grow a drug called qat.With one of the world's highest rates of population growth--3.46 percent, Yemen is the poorest Arab country. The government is considering desalinating seawater,but this would be expensive and it may now be too late.The only other solution is to cut down on farming, but that means importing even more food. When Hannan said that only the rich could prepare for cuts in supply,she meant that _ . A) rich people drank more water than the poor B) rich people could buy water from the water trucks if there was a water supply cut C) she had a rich neighbor who often helped her during water supply cuts D) the rich were not affected by water supply cuts
Answer:
B