Caffeine not only gives us a daily jump start, but new research suggests it also can strengthen long-term memory.
According to the US Food and Drug Administration, nearly 90 percent of people worldwide consume about 200 milligrams of caffeine each day. That' s equivalent to about one strong cup of coffee a day. Writing in " Nature Neuroscience" , Johns Hopkins University researchers say their findings show that caffeine strengthens certain memories for up t0 24 hours after being taken in.
" We've always known that caffeine has cognitive-enhancing effects (促智效果) , but its ,particular effects on strengthening memories and making them resistant to forgetting has never been examined in detail in humans, " said senior author of the paper Michael Yassa. " We re- port for the first time a specific effect of caffeine on reducing forgetting over 24 hours. " Conducting a double-blind trial, the researchers worked with a test group of people who didn't regularly consume caffeinated products. Five minutes after studying a series of images, the test subjects were given either a placebo(无效对照剂) or a 200-milligram caffeine tablet.
To check the caffeine levels of their test subjects, the research team took saliva samples (唾液样品) from them before they took their tablets and again one, three and 24 hours after- wards.
Both groups of test participants ( those who took the placebo and those who took the caffeine tablet) were tested the following day to see if they could recognize the images they' d seen the previous day.
The test included showing the test subjects another series of images that included some new images , those that were shown the previous day, as well as other images that were similar, but not the same as those they had viewed earlier.
The researchers found that more members of the group who were given the caffeine tablets were able to correctly identify some of the new images as " similar" to previously viewed images rather than incorrectly identifying them as the same.
"We also know that caffeine is associated with health and longevity(长寿) and may havesome protective effects from cognitive decline like Alzheimer' s disease (阿尔茨海默症). " said Yassa.The purpose of the new research is
| A．to survey how much caffeine people consume a day |
| B．to write the paper " Nature Neuroscience" |
| C．to prove caffeine has cognitive-enhancing effects |
| D．to examine caffeine ' s memory-strengthening effects in detail |
During the research ,the researchers did the following things EXCEPT
| A．giving the test subjects placebos or caffeine tablets |
| B．checking the caffeine levels of the test subjects |
| C．encouraging the test subjects to drink more coffee |
| D．showing the test subjects series of images |
How did the test subjects show the caffeine ' s memory-strengthening effects?
| A．By recognizing images they ' d seen the previous day. |
| B．By taking the caffeine tablets instead of placebos. |
| C．By identifying the new images as the same. |
| D．By telling the differences between new images. |
What will the next part of the text possibly talk about?
| A．Ways to achieve health and longevity. |
| B．The effects caffeine has on health. |
| C．The treatment for Alzheimer' s disease. |
| D．The harmful effects of cognitive decline. |
We know that many animals do not stay in one place. Birds, fish and other animals move from one place to another at a certain time. They move for different reasons most of them move to find food more easily, but others move to get away from places that are too crowded. When cold weather comes, many birds move to warmer places to find food. Some fishes give birth in warm water and move to cold water to feed. The most famous migration（迁移）is probably the migration of the fish, which is called “salmon”. This fish is born in fresh water but it travels many miles to salt water. There it spends its life. When it is old, it returns to its birthplace in fresh water. Then it gives birth and dies there. In northern Europe, there is a kind of mice. They leave their mountain homes when they become too crowded. They move down to the low land. Sometimes they move all the way to the seaside, and many of them are killed when they fall into the sea.
Recently, scientists have studied the migration of a kind of lobsters（龙虾）. Every year, when the season of bad weather arrives, the lobsters get into a long line and start to walk across the floor of the ocean. Nobody knows why they do this, and nobody knows where they go. So, sometimes we know why humans and animals move from one place to another, but at other times we don’t. Maybe living things just like to travel.
Most animals move from one place to another at a certain time to __________ .
A. give birth B. enjoy warmer weather
C. find food more easily D. find beautiful places
54. The mice in northern Europe move when __________ .
A. they give birth B. the weather is bad
C. the place gets too crowdedD. they haven’t enough food
55. The lobsters move __________ .
A. to the fresh water B. to the sea floor
C. to find more food D. at a certain time
56. What is the main idea of the passage?
A. Animals move in order to find food more easily.
B. The migration of the fish called “salmon” is the most famous migration.
C. Living things move from one place to another because they like to travel.
D. Sometimes we know why and how living things move from one place to another but we don’t sometimes.
When Johnson called again, the manager received him very politely. “That is a most remarkable oil you brought us, Mr Johnson,” he said. Johnson nodded his smooth, dark head. That was something he knew very well.“I've never seen anything like it,” the manager admitted. Johnson nodded again.“No?” he said politely. Then he added, “But I think you will, sir. A very great deal of it.” He appeared to think for a moment. “I think you will find it will be on sale seven, perhaps, eight years from now.” He smiled.
The manager thought that was uncertain. He said, “It is better than our fish oils. I admit that.”“So I am told, sir,” agreed Johnson.
“Have you any plans to produce it yourself, Mr Johnson?” Johnson smiled again.
“Would I be showing it to you if I had?”
“We might add some chemicals to one of our own fish oils,” said the manager.“It would be expensive to do that, even if you could,” Johnson said gently.“Besides,” he added,“I am told that this oil will be much cheaper than your best fish oils. Cheaper than any vegetalbe oil, in fact.”
“Perhaps,” said the manage.“Well, I suppose you want to make an arrangement, Mr Johnson. Shall we discuss it?”
“Of course,” said Johnson. “There are two ways of dealing with a situation of this sort. The usual one is to prevent it altogether or at least to delay it as long as possible. That is, of course, the best way.” The manager nodded. He knew plenty about all that.
“But I am so sorry for you, because, you see, that is not possible this time.” The manager had his doubts, but all he said was an inquiring(asking), “Oh?”
“The other way,” continued Johnson,“is to produce yourself before the trouble starts.”
49.The manager thought of adding chemicals to the fish oil to make it ______.
A.cheaper than the new oil B.more quickly
C.more expensive D.as good as the new oil
50.Johnson's new oil would be ______.
A.more expensive than fish oil, but betterB.less expensive, and better
C.less expensive, but not goodD.more expensive, and not so good
51.Johnson expressed his regret that the manager ______.
A.could not stop the new oil being made B.would never know how to make it
C.had spent a lot of money on it D.didn't know enough about it
52.Johnson showed his new oil to the manager because he wanted ______.
A.to produce it himself B.to prevent it being produced
C.to be paid not to produce it D.the manager to produce it
Archaeology as a profession faces two major problems. It is the poorest of the poor. Only small sums are available for excavating(挖掘)and even less is available
for publishing the results and preserving the sites once excavated. Yet archaeologists deal with priceless objects every day. Besides, there is the problem of unlawful excavation, resulting in museum-quality pieces being sold to businessmen at the highest price..
I would like to make a suggestion that would at once provide money for archaeology and reduce the amount of diggings against law. You might say that professionals excavate to get knowledge, not money. Moreover, ancient artifacts(古器
物) are part of our global cultural heritage(遗产), which should be there for all to appreciate, not sold at the highest price. I agree. Sell nothing that has scientific value. But, you might reply, everything that comes out of the ground has scientific value. Here,
we disagree. In theory, you may be correct in saying that every artifact has hidden scientific value..
People can not help appreciate every unearthed treasure but there is not enough money even to put the finds in good order; as a result, they cannot be found again and become as inaccessible as if they had never been discovered. Indeed, with the help of the Internet, sold artifacts could be more reachable than are the pieces stored in museum basements. Before sale, each could be photographed and the list of the purchasers could be maintained on the computer. A purchaser could even be required to agree to return the piece if it should become needed for scientific purposes.
53.What’s the problems that archaeology as a profession has to face?
A. Money and unlawful excavation . B. Effectively duplicates.
C. Scientific purposes. D. Excavation law.
54.To let most people enjoy ancient artifacts, the practical way could be_______.
A. putting them in the museumB. having sold artifacts returned
C. making use of the Internet D. solving the money problem
55.Which of the following four suggestions about archaeology is from the author?
A. No selling of any unearthed ancient artifacts.
B. Some money should be raised for the purpose.
C. Selling some unearthed ancient artifacts and having them returned when needed.
D. Ancient artifacts, our global cultural heritage, should be evenly shared by us all.
New York Times---( DINITIA SMITH )Tomorrow is the 433d anniversary of Shakespeare's birth. A recent survey shows that more people are watching him, reading him and studying him than ever before.
Consider the recent yearly conference of the Shakespeare Association of America in Washington, where more than 600 people who study or admire Shakespeare from 18 countries took in topics like ''Whither Attribution Studies,'' ''Unpopular Shakespeare'' and ''Sex Me Here,'' a talk on breast-feeding and Lady Macbeth.
''The national media is saying that fewer students' taking Shakespeare,'' Barbara Mowat, the editor of The Shakespeare Quarterly, observed in a speech at the conference. ''But Shakespeare is thriving.'' The association's membership has increased by a third since 1990.
The Shakespeare business is so good these days that W. W. Norton is introducing a huge new collections of the plays into the already crowded field just in time for tomorrow's birthday anniversary. Priced at $44.95, ''The Norton Shakespeare: Based on the Oxford Edition'' runs for 3,420 pages, offering introductions, illustrations and notes and three versions(版本) of ''King Lear.''
Today, movies and videos have made the plays even more accessible. Last year, ''William Shakespeare's Romeo and Juliet'' was No. 1 at the box office when it opened, and it grossed nearly $50 million. In New York in January, crowds lined up in the freezing cold to see Kenneth Branagh's four-hour ''Hamlet.'' The students select a scene and then have a violent discussion about it.'' Influenced by films, professors are increasingly teaching students by having them perform the plays.
49.Why people from 18 countries came to Washington this year?
A. To celebrate Shakespeare’s 433d birth day only.
B. To watch some plays by Shakespeare as planned.
C. To celebrate Shakespeare’s birthday and study his works.
D. To discuss how to teach students using Shakespeare’s plays.
50. What does the underlined word “ field” in the fourth paragraph refer to?
A. Washington D.C.B. Shakespeare Association.
C. The birthday anniversary. D. The Shakespeare business.
51.Which of the many plays by Shakespeare was most popular the year before?
A. King Lear. B. Hamlet. C. Macbeth. D. Romeo and Juliet.
52.What does the author want to prove by using so many examples about Shakespeare?
A. More and more people are becoming interested in Shakespeare.
B. Shakespeare business is being run well in America nowadays.
C. Plays by Shakespeare can be used at school for more studies.
D. Shakespeare belongs not only to Britain but also to the USA.
Did you ever wonder how some of your favorite foods, products or toys came about? Believe it or not, they may have been an accident, or a failure of some other intention. Below, we found three mistakes we're thankful for turned out to be what they are.
1. Most historians hold that the Chinese invented fireworks in the 9th century when they
discovered how to make gunpowder. Story has it that a Chinese cook accidentally mixed together what were then considered common kitchen items and noticed they burnt. When put tightly in a bamboo tube and lit, it blew up.
2. In May of 1886, a law led John Pemberton, a pharmacist（药剂师）, to rewrite the formula(配方) for "Pemberton's French Wine Coca,” his popular headache treatment. Containing sugar instead of wine as a sweetener, the outcome became something for Coke, which was later mixed with carbonated water. His bookkeeper suggested the name Coca-Cola because he thought the two C’s would look good together, which is how what we call Coca-Cola, a world –wide drink came into being.
3. During World War II, scientists at the University of Birmingham invented the magnetron—an important heat-producing part of the microwave oven(微波炉). While working for Raytheon Corporation after the war, the American engineer Percy Spencer was testing the magnetron when a chocolate bar in his pocket melted. He went on to test other foods including popcorn kernels, and found it to be a much more efficient way to cook. In 1947 Raytheon came out with the first restaurant microwave oven, which was six feet tall and weighed 750 lbs.
45.The right time order of the three inventions, according to the passage, should be______.
A. fireworks, the microwave and Coca-Cola
B. fireworks ,Coca-Cola and the microwave
C. Coca-Cola , fireworks and the microwave
D. the microwave, Coca-Cola and fireworks
46.Percy Spencer found the microwave efficient in cooking when he was _______
A. looking for a way to melt his chocolate
B. trying to know how a magnetron could cook
C. working to know how the magnetron works
D. asked to invent a restaurant microwave oven
47. What can we learn from the above invention stories?
A. Experiments make great inventors of our time.
B. Nothing is impossible if one tries each day.
C. Inventors come out of hard work at any time.
D. A small incident may lead to a great invention.
48.What’s the best title for the passage?
A. What great inventions they are! B. Inventions from Three Countries.
C. Stories of Accidental Inventions.D. The Human Inventions of time.