出自:河南师范大学-行政管理（本科）-大学英语Ⅱ
Brazil has become one of the developing world‘s great successes at reducing population growth-but more by accident than design. While countries such as India have made joint efforts to reduce birth rates, Brazil has had better result without really trying, says George Martine at Harvard. Brazil‘s population growth rate has dropped from 2. 99%a year between 1951 and 1960 to 1. 93%a year between 1981 and 1990, and Brazilian women now have only 2. 7 children on average. Martine says this figure may have fallen still further since 1990, an achievement that makes it the envy of many other Third World countries. Martine puts it down to, among other things, soap operas (通俗电视连续剧)and installment (分期付款)plans introduced in the 1970s. Both played an important, although indirect, role in lowering the birth rate. Brazil is one of the world‘s biggest producers of soap operas. Globo, Brazil‘s most popular television network, shows three hours of soaps six nights a week, while three others show at least one hour a night. Most soaps are based on wealthy characters living the high life in big cities. “Although they have never really tried to work in a message towards the problems of
The biggest safety threat facing airlines today may not be a terrorist with a gun, but the man with the portable computer in business class. In the last 15 years, pilots have reported well over 100 incidents that could have been caused by electromagnetic interference. The source of this interference remains unconfirmed, but increasingly, experts are pointing the blame at portable electronic device such as portable computers, radio and cassette players and mobile telephones.
RTCA, an organization which advises the aviation (航空)industry, has recommended that all airlines ban (禁止)such devices from being used during “critical”stages of flight, particularly take-off and landing. Some experts have gone further, calling for a total ban during all flights. Currently, rules on using these devices are left up to individual airlines. And although some airlines prohibit passengers from using such equipment during take-off and landing, most are reluctant to enforce a total ban, given that many passengers want to work during flights.
There seems never to have been a civilization without toys, but when and how they developed is unknown. They probably came about just to give children something to do.
In the ancient world, as is today, most boys played with some kinds of toys and most girls with another. In societies where social roles are rigidly determined, boys pattern their play after the activities of their fathers and girls after the tasks of their mothers. This is true because boys and girls are being prepared, even in play, to step into the roles and responsibilities of the adult world.
What is remarkable about the history of toys is not so much how they changed over the centuries but how much they have remained are same. The changes have been mostly in terms of craftsmanship, mechanics, and technology. It is the universality of toys with regard to their development in all parts of the world and their persistence to the present that is amazing. In Egypt, the Americas, China, Japan and among the Arctic (北极的)peoples, generally the same kinds of toys appeared. Variations depended on local customs and ways of life because toys imitate their surroundings. Nearly every civilization had dolls, little weapons, toy soldiers, tiny animals and vehicles.
Believe it or not, optical illusion (错觉)can cut highway crashes.
Japan is a case in point. It has reduced automobile crashes on some roads by nearly 75 percent using a simple optical illusion. Bent stripes, called chevrons (人字形), painted on the roads make drivers think that they are driving faster than they really are, and thus drivers slow down.
Now the American Automobile Association Foundation for Traffic Safety in Washington D. C. is planning to repeat Japan‘s success. Starting next year, the foundation will paint chevrons and other patterns of stripes on selected roads around the country to test how well the patterns reduce highway crashes.
Excessive speed plays a major role in as much as one fifth of all fatal traffic accidents, according to the foundation. To help reduce those accidents, the foundation will conduct its tests in areas where speed-related hazards are the greatest—curves, exit slopes, traffic circles, and bridges.
Some studies suggest that straight, horizontal bars painted across roads can initially cut the average speed of drivers in half. However, traffic often returns to full speed within months as drivers become used to seeing the painted bars.
Why does cram go bad faster than butter?Some researchers think they have the answer, and it comes down to the structure of the food, not its chemical composition—a finding that could help rid some processed foods of chemical preservatives. 【外语教育&网www.for68.com】
Cream and butter contain pretty much the same substances, so why cream should sour much faster has been a mystery. Both are emulsions—tiny globules (小球体)of one liquid evenly distributed throughout another. The difference lies in what‘s in the globules and what‘s in the surrounding liquid, says Brocklehurst, who led the investigation.
In cream, fatty globules drift about in a sea of water. In butter, globules of a watery solution are locked away in a sea of fat. The bacteria which make the food go bad prefer to live in the watery regions of the mixture. “This means that in cream, the bacteria are free to grow throughout the mixture, ”he says.
When the situation is reversed, the bacteria are locked away in compartments (隔仓室)buried deep in the sea of fat. Trapped in this way, individual colonies cannot spread and rapidly run out of nutrients (养料). They also slowly poison themselves with their waste products. “In butter, you get a self-limiting system which stops the bacteria growing, ”says Brocklehurst.
Ancient Greek philosopher Aristotle viewed laughter as “a bodily exercise precious to health.” But ---__1___some claims to the contrary, laughing probably has little influence on physical fitness Laughter does __2___short-term changes in the function of the heart and its blood vessels, ___3_ heart rate and oxygen consumption But because hard laughter is difficult to __4__, a good laugh is unlikely to have __5___ benefits the way, say, walking or jogging does.
__6__, instead of straining muscles to build them, as exercise does, laughter apparently accomplishes the __7__, studies dating back to the 1930’s indicate that laughter__8___ muscles, decreasing muscle tone for up to 45 minutes after the laugh dies down.
Such bodily reaction might conceivably help _9__the effects of psychological stress. Anyway, the act of laughing probably does produce other types of ___10___ feedback, that improve an individual’s emotional state. __11____one classical theory of emotion, our feelings are partially rooted ____12___ physical reactions. It was argued at the end of the 19th century that humans do not cry ___13___they are sad but they become sad when the tears begin to flow.
Research on animal intelligence always makes me wonder just how smart humans are. 1 the fruit-fly experiments described in Carl Zimmer’s piece in the Science Times on Tuesday. Fruit flies who were taught to be smarter than the average fruit fly 2 to live shorter lives. This suggests that 3 bulbs burn longer, that there is an 4 in not being too terrifically bright.
Intelligence, it 5 out, is a high-priced option. It takes more upkeep, burns more fuel and is slow 6 the starting line because it depends on learning — a gradual 7 — instead of instinct. Plenty of other species are able to learn, and one of the things they’ve apparently learned is when to 8 .
Is there an adaptive value to 9 intelligence? That’s the question behind this new research. I like it. Instead of casting a wistful glance 10 at all the species we’ve left in the dust I.Q.-wise, it implicitly asks what the real 11 of our own intelligence might be. This is 12 the mind of every animal I’ve ever met.
Research on animal intelligence also makes me wonder what experiments animals would 13 on humans if they had the chance. Every cat with an owner, 14 , is running a small-scale study in operant conditioning. we believe that 15 animals ran the labs, they would test us to determine the limits of our patience, our faithfulness, our memory for terrain. They would try to decide what intelligence in humans is really for , not merely how much of it there is. Above all , they would hope to study a fundamental question: Are humans actually aware of the world they live in? So far the results are inconclusive.
The idea that some groups of people may be more intelligent than others is one of those hypotheses that dare not speak its name. But Gregory Cochran is 1 to say it anyway. He is that 2 bird, a scientist who works independently 3 any institution. He helped popularize the idea that some diseases not 4 thought to have a bacterial cause were actually infections, which aroused much controversy when it was first suggested.
5 he, however, might tremble at the 6 of what he is about to do. Together with another two scientists, he is publishing a paper which not only 7 that one group of humanity is more intelligent than the others, but explains the process that has brought this about. The group in 8 are a particular people originated from central Europe. The process is natural selection.
This group generally do well in IQ test, 9 12-15 points above the 10 value of 100, and have contributed 11 to the intellectual and cultural life of the West, as the 12 of their elites, including several world-renowned scientists,13 hey also suffer more often than most people from a number of nasty genetic diseases, such as breast cancer. These facts, 14 ave previously been thought unrelated. The former has been 15 social effects, such as a strong tradition of valuing ucation. The latter was seen as a (an) consequence genetic isolation. Dr. Cochran suggests that the intelligence and diseases are intimately linked is
The outbreak of swine flu that was first deteccted in Mexico was declared a global epidemic on june 11,2009. It is the first wotldwide cpidemic__1__by the World Health Organization in41years.
The heightened alert __2__an emergency meeting with flu experts in Geneva that assembled after a sharp pise in cases in Australia.and rising __3__in Britain ,japan,Chile and elsewhere.
Bur the epiemic is “__4__”in severity. According to Margaret Chan. The organization’s director general,__5__the overwhelming majorty of patients experiencing only mild symptoms and full recovery. Often in the__6__of any medical treatment.
The ourbreak came to gobal__7__in lafe April2009.when Mexican authorities noted an unusually latge number of hospitalizations and deaths__8__ healthy adults. As much ofMexico City Shut down at the height of a panic,cases began to__9__in New York City.the southwestem United States and atound the world.
In the United States, new cases seemed to fade__10__warmer weather arrived.But in late September 2009,officials reported there was__11__flu activity in almost every state and that virtually all the__12__tested are the new swine flu. Also known as(A)H1N1,not seasonal flu.In the U.S.,It has__13__more than one million people,and caused mone than 600 deaths and more than 6,000 hospitalizations.