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Less Is More
It sounds all wrong—drilling holes in a piece of wood to make it more resistant to knocks. But it works because the energy from the blow gets distributed throughout the wood rather than fo-
cusing on one weak spot. The discovery should lead to more effective and lighter packaging mate-rials.
Carpenters have known______(51)centuries that some woods are tougher than others. Hickory,for example,was turned into axe handles and cartwheel spokes because it can absorb shocks without breaking. White oak,for example,is much more easily damaued,________(52)it is almostas dense.Julian Vincent at Bathe University and his team were convinced the wood's internal structure could explain the differences.
Many trees have tubular vessels that run_______(53)the trunk and carry water to the leav- es .In oak they are large,and arranged in narrow bands,but in hickory they are smaller,and more evenly distributed.The researchers________(54)this layout might distribute a blow's en-ergy throughout the wood, soaking up a bigger hit.To test the idea,they drilled holes 0.65 millimetres across into a block of spruce,a wood with_______(55)vessels,and found that_______(56)withstood a harder knock_______(57)when there were more than about 30 holes per square centimeter did the wood's performance drop off.
A uniform substance doesn't cope well with knocks because only a small proportion of the material is actually______( 58).All the energy from the blow goes towards breaking the material in one or two places , but often the pieces left _________( 59 ) are pristine(未经破坏的).
But instead of the energy being concentrated in one place,the holes provide many weak spots that all absorb energy as they break,says Vincent.“You are controlling the places______(60) the wood breaks,and it can then absorb more______(61),more safely.”
The researchers believe the principle could be applied to any material—_________(62)example,to manufacture lighter and more protective packaging.It could_______(63)be used in car bumpers,crash barriers and armor for military vehicles,says Ulrike Wegst,_______(64) the Max Plank Institute for Mental Research in Stuttgart. But she emphasizes that you'd ________(65)to design the substance with the direction of force in mind.“The direction of loading is crucial,”she says.
53._________
A: down
B:.over
C: up
D:.into

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EL Nino
While some forecasting methods had limited success predicting the 1997 EL Nino(厄尔尼诺现象,指赤
道东太平洋南美沿岸海水温度剧烈上升的现象。) a few months in advance , the Columbia University
researchers say their method can predict large EL Nino events up to two years in advance.That would be
good news for governments,farmers and others seeking to plan for the droughts and heavy rainfall that EL
Nino can produce in various parts of the world.
Using a computer,the researchers matched sea-surface temperatures to later EL Nino occurrences(发
生)between 1980 and 2000 and were then able to anticipate EL Nino events dating back to 1857,using prior
sea-surface temperatures.The results were reported in the latest issue of the journal Nature.
The researchers say their method is not perfect , but Bryan C. Weare , a meteorologist(气象学家)at the
University of California,Davis,who was not involved in the work,said it"suggests EL Nino is indeed
predictable".
"This will probably convince others to search around more for even better methods,"said Weare.He
added that the new method " makes it possible to predict EL Nino at long lead(提前的)times ". Other
models also use sea-surface temperatures,but they have not looked as far back because they need other data,
which is only available for recent decades,Weare said.
The ability to predict the warming and cooling of the Pacific is of immense importance.The 1997 EL
Nino , for example , caused an estimated $20 billion in damage worldwide , offset(抵消)by beneficial effects
in other areas,said David Anderson,of the European Centre for Medium-Range Weather Forecasts in
Reading , England. The 1877 EL Nino , meanwhile , coincided(同时发生)with a failure of the Indian monsoon
and a famine that killed perhaps 40 million in India and China,prompting the development of seasonal
forecasting,Anderson said.
When EL Nino hit in 1991 and 1997,200 million people were affected by flooding in China alone,
according to a 2002 United Nations report.
While predicting smaller EL Nino events remains tricky(复杂的), the ability to predict larger ones
should be increased to at least a year if the new method is confirmed.
EL Nino tends to develop between April and June and reaches its peak between December and
February.The warming tends to last between 9 and 1 2 months and occurs every two to seven years.
The new forecasting method does not predict any major EL Nino events in the next two years,although a
weak warming toward the end of this year is possible.
Weare's contribution in predicting EL Nino was highly praised by other meteorologists.
A:Right
B:Wrong
C:Not mentioned
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The Benefits of Lifelong Learning for Adults
Lifelong learning is the process of keeping your mind and body engaged一at any age一by actively pursuing knowledge and experience.In fact,it has many benefits.Firstly,it keeps the mind sharp and it improves the memory.Secondly,it improves self-confidence and offers an opportunity to try something new. Thirdly,it gives the learner the feeling of accomplishment. Also,it offers the learner the opportunity to keep in touch with people who share with him/her the same interests and make new acquaintances.Finally,it offers an opportunity to learn a new skill or trade.
Achieving retirement means having a lot of spare time and becoming more stressed and bored. However,some adults think that learning at that age is a way to get rid of this situation of boredom and stress.For them learning should be a lifelong process and even retirement should be an opportunity to try new things rather than being passive and pessimistic.
Lifelong learning helps you remember things better.
A:Right
B:Wrong
C:Not mentioned
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Why would They Falsely Confess?
Why on earth would an innocent person falsely confess to committing a crime?To most people,it just doesn't seem logical. But it is logical,say experts,if you understand what can happen in a police interrogation(审讯)room.
Under the right conditions,people's minds are susceptible(易受影响的)to influence , and the pressure put on suspects during police grillings(盘问)is enormous. ________ (1)“The pressure is important to understand,because otherwise it's impossible to understand why someone would say he did something he didn't do. The answer is:to put an end to an uncom-fortable situation that will continue until he does confess.”
Developmental psychologist Allison Redlich recently conducted a laboratory study to de- termine how likely people are to confess to things they didn't do.______(2)The research-ers then intentionally crashed the computers and accused the participants of hitting the“alt” key to see if they would sign a statement falsely taking responsibility.
Redlich's findings clearly demonstrate how easy it can be to get people to falsely con- fess:59% percent of the young adults in the experiment immediately confessed. ______(3) of the 15-to 16-year-olds,72 percent signed confessions,as did 78 percent of the 12-to 13- year-olds.
“There's no question that young people are more at risk,”says Saul Kassin,Professor at Williams College,who has done similar studies with similar results.______(4)
Both Kassin and Redlich note that the entire“interrogation” in their experiments consis-ted of a simple accusation一not hours of aggressive questioning一and still,most participants falsely confessed.
Because of the stress of a police interrogation,they conclude,suspects can become con- vinced that falsely confessing is the easiest way out of a bad situation. ______(5)
_______(4)
A: In her experiment,participants were seated at computers and told not to hit the“alt” key,because doing so would crash the systems.
B:“In some ways,”says Kassin,“false confession becomes a rational decision.”
C: “It's a little like somebody's working on them with a dental(牙的)drill , ” says Frank- lin Zimring,a law professor at the University of California at Berkeley.
D:“But adults are highly vulnerable too.”
E: How could an innocent person admit to doing something he didn't do?
F: Redlich also found that the younger the participant,the more likely a false confession.
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The Greatest Mystery of Whales
The whale is a warm一blooded,air-breathing animal,giving birth to its young alive,sucking them一and,
like all mammals,originated on land. There are many________________(51)of this. Its front flippers(鳍状肢),
used for steering and stability,are traces of feet.
Immense strength is________________(52)into the great body of the big whales,and in fact most of a
whale's body is one gigantic muscle.The blue whale's pulling strength has been estimated________________(53)
400 horsepower. One specimen was reported to have towed(拖)a whaling vessel for seven hours at the
_______________ (54)of eight knot(节).
An angry whale will________________(55).A famous example of this was the fate of Whaler Essex,
________________(56)was sunk off the coast of South America early in the last century. More recently,steel ships
have ___________( 57 ) their plates buckled(使弯曲)in the same way. Sperm whales(抹香鲸)were known
to seize the old-time whaleboats in their jaws and crush them.
The greatest________________(58)of whales is their diving ability.The sperm whale dives to the bottom foi
his________________(59)food,the octopus(章鱼).In that search he is known to go as far down as 3 , 200 feet,
where the________________(60)is 1,400 pounds,to a square inch.Doing so he will________________(61)underwa-
ter as long as one hour. Two special skills are involved in this storing up enough________________(62)(all
whales are air-breathed)and tolerating the great change in pressure.Just how he does it scientists have nol
_______________ (63).It is believed that some of the oxygen is stored in a special________________(64)of blood
vessels,rather than just held in the lungs.And it is believed that a special kind of oil in his head is some sort
of a compensating mechanism that________________(65)adjusts the internal pressure of his body.But since you
can't bring a live whale into the laboratory for study,no one knows just how these things work.
_________(62)
A:heat
B:energy
C:food
D:oxygen
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Smoking can Increase Depressive Symptoms in Teens
While some teenagers may use cigarettes to "self-medicate"(自我治疗)against the blues(忧郁),sci-
entists at the University of Toronto and the University of Montreal have found that smoking may actually
______________
(51)depressive symptoms in some teens.
"This observational study is one of the few to examine the perceived ______________(52)benefits of
smoking among teens,"says lead researcher Michael Chaiton,a research associate at the Ontario Tobacco
Research Unit of the University of Toronto."_______________(53)cigarettes may appear to have self-medicating
effects or to improve mood,in the long_______________(54)we found that teens who started to smoke reported
higher depressive symptoms."
As part of the study,some 662 high school teenagers completed up to 20 questionnaires about their use
of cigarettes to ______________
(55)mood.Secondary schools were selected to provide a mix of French and
English participants,urban and rural schools,and schools ______________(56)in high,moderate and low so-
cioeconomic neighbourhoods.
Participants were divided into three
______________ (57):never smokers;smokers who did not use ciga-
rettes to self-medicate,improve mood or physical
______________ (58);smokers who used cigarettes to self-
medicate.Depressive symptoms were measured using a scale that asked how often participants felt too tired
to do things;had
______________ (59)going to sleep or staying asleep;felt unhappy,sad,or depressed;felt
hopeless about the future;felt anxious or tense;and worried too much about things.
" Smokers who used cigarettes as mood
______________( 60 ) had higher risks of elevated(提升)depres-
sive symptoms______________ (61)teens who had never smoked,"says co-researcher Jennifer O'Loughlin,a
professor at the University of Montreal Department of Social and Preventive Medicine."Our study found that
teen smokers who reported emotional benefits from smoking are_______________(62)higher risk of developing
depressive symptoms."
The______________ (63)between depression and'smoking exists______________(64)among teens that use
cigarettes to feel better."It's ______________(65)to emphasize that depressive symptom scores were higher
among teenagers who reported emotional benefits from smoking after they began to smoke,"says Dr. Chaiton.
_________(59)
A:time
B:courage
C:trouble
D:energy
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