相关试题
共用题干
More Than 8 Hours Sleep Too Much of a Good Thing
1 Although the dangers of too little sleep are widely known,new research suggests that people who sleep too much may also suffer the consequences.
2 Investigators at the University of California in San Diego found that people who clock up 9 or 10 hours each weeknight appear to have more trouble falling and staying asleep,as well as a number of other sleep problems,than people who sleep 8 hours a night. People who slept only 7 hours each night also said they had more trouble falling asleep and feeling re-freshed after a night's sleep than 8-hour sleepers.
3 These findings,which DL Daniel Kripke reported in the journal Psychosomatic Medicine,demonstrate that people who want to get a good night's rest may not need to set aside more than 8 hours a night.He added that“it might be a good idea” for people who sleep more than 8 hours each night to consider reducing the amount of time they spend in bed,but cau-tioned that more research is needed to confirm this.
4 Previous studies have shown the potential dangers of chronic shortages of sleep一for instance,one report demonstrated that people who habitually sleep less than 7 hours each night have a higher risk of dying within a fixed period than people who sleep more.
5 For the current report,Kripke reviewed the responses of 1,004 adults to sleep ques-tionaires,in which participants indicated how much they slept during the week and whether they experienced any sleep problems. Sleep problems included waking in the middle of the night,arising early in the morning and being unable to fall back to sleep,and having fatigue interfere with day-to-day functioning.
6 Kripke found that people who slept between 9 and 10 hours each night were more like-ly to report experiencing each sleep problem than people who slept 8 hours. In an interview, Kripke noted that long sleepers may struggle to get rest at night simply because they spend too much time in bed. As evidence,he added that one way to help insomnia is to spend less time in bed.“It stands to reason that if a person spends too long a time in bed,then they'll spend a higher percentage of time awake.”he said.
Paragraph 4______
A: Kripke's Research
B: Dangers of Habitual Shortages of Sleep
C: Criticism on Kripke's Report
D: A way of Overcoming Insomnia
E: Sleep Problems of Long and Short Sleepers
F: Classification of Sleep Problems
共用题干
Improve Your Memory
To many people advancing age means losing your hair,your waistline and your memory.But is it an inescapable fact that the older you get,the less you remember? Well,as time goes by,we tend to blame age for problems that are not necessarily age-related.
When a teenager can't find her keys,she thinks it's because she's distracted or disorganized, but a 70-year-old blames her memory. In fact,the 70-year-old may have been misplacing things for decades一like we all do from time to time.
In healthy people,memory doesn't deteriorate as quickly as many of us think. According to psychologists,as we age,our memory mechanism isn't broken,it's just different.The brain's processing time slows down over the years,though no one knows exactly why.Recent research suggests that nerve cells lose efficiency and that there's less activity in the part of the brain that decides whether to store information or not.But it's not clear that less activity is worse.A beginning athlete is winded. more easily than a trained athlete.In the same way,as the brain gets more skilled at a task,it spends less energy on it.
There are steps you can take to improve your memory,though you have to work to keep your brain in shape.It's like having a good body. You can't go to the gym once a year and expect to stay in top form.
Some memory enhancement experts suggest using the AM principle.Pay attention to what you want to remember. Then give some meaning to it. We remember things when we focus on them, whether we intend to or not. That helps explain why jingles stick in our minds.They are played on loud,flashy TV commercials.They also use rhyme and music to help us remember better.
Basic organization helps us remember the boring stuff. For example,rather than trying to recall a random list of groceries,we can divide them into categories,such as dairy,meat and produce. For important things like keys and money,we can set up a"forget-me-not"spot where we always keep them.
We can also eat to aid our memory power. Whole grains,fruits and vegetables are excellent sources of glucose,the brain's preferred fuel. Another low-tech way to improve memory is to get adequate rest. Sleep may allow our brain time to encode memories.
Interest in friends,family and hobbies does wonders for our memory.A sense of passion or purpose helps us remember. Memory requires us to pay attention to our lives,allowing us to discover in them everything worth remembering.
In the AM principle,the letters A and M most likely refer to attention and memory respectively.
A:Right
B:Wrong
C:Not mentioned
共用题干
第一篇
Can Buildings Be Designed to Resist Terrorist Attack?
In the aftermath of the terrorist attack on the World Trade Center,structural engineers are trying hard to
solve a question that a month ago would have been completely unthinkable:Can buildings be designed to
withstand catastrophic blasts inflicted by terrorists?
Ten days after the terrorist attacks on the twin towers,structural engineers from the University at Buffalo
and the Multidisciplinary Center for Earthquake Engineering Research(MCEER)headquartered at UB
traveled to ground zero as part of a project funded by the National Science Foundation.Visiting the site as
part of an MCEER reconnaissance visit,they spent two days beginning the task of formulating ideas about
how to design such structures arid to search for clues on how to do so in buildings that were damaged but still
are standing.
"Our objective in visiting ground zero was to go and look at the buildings surrounding the World Trade
Center,those buildings that are still standing,but that sustained damage,"said M.Bruneau,Ph.D."Our im-
mediate hope is that we can develop a better understanding as to why those buildings remain standing,while
our long-term goal is to see whether earthquake engineering technologies can be married to existing technolo-
gies to achieve enhanced performance of buildings in the event of terrorist attacks,"he added.
Photographs taken by the investigators demonstrate in startling detail the monumental damage inflicteed
on the World Trade Center towers and buildings in the vicinity.One building a block away from the towers
remains standing,but was badly damaged."This building is many meters away from the World Trade Center
and yet we see a column there that used to be part of that building,"explained A.Whittaker,Ph.D."The
column became a missile that shot across the road,through the window arid through the floor."
The visit to the area also revealed some surprises,according to the engineers.For example,the floor
framing system in one of the adjacent buildings was quite rugged,allowing floors that were pierced by tons of
falling debris to remain intact. " Highly redundant ductile（有延展性的）framing systems may provide a sim-
pie,but robust strategy for blast resistance,"he added.Other strategies may include providing alternate paths
for gravity loads in the event that a load一bearing column fails."We also need a better understanding of the
mechanism of collapse,"said A.Whittaker."We need to find out what causes a building to collapse and how
you can predict it."
A.Reinhorn,Ph.D.noted that"Earthquake shaking has led to the collapse of many buildings in the
past.It induces dynamic response and extremely high stresses and deformations in structural components.So-
lutions developed for earthquake-resistant design may be directly applicable to blast engineering and
terrorist-resistant design.Part of our mission now at UB is to transfer these solutions and to develop new ones
where none exist at present."
The question raised in the first paragraph is one_______.
A:that was asked by structural engineers a month ago
B:that is too difficult for structural engineers to answer even now
C:that was never imagined before the terrorist attack
D:that terrorists are eager to find a solution to
共用题干
The Northern Lights
The Sun is stormy and has its own kind of weather It is so hot and active that even the Sun's gravity cannot hold its atmosphere in check!Energy flows away from the Sun toward the Earth in a stream of electrified particles that move at speeds around a million miles per hour. These particles are called plasma,and the stream of plasma coming from the Sun is called the solar wind. The more active the Sun,the stronger the solar wind.
The solar wind constantly streams toward the Earth,but don't worry because a protective magnetic field surrounds our planet.The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles.The charged particles become trapped in magnetic belts around the Earth. When a large blast of solar wind crashes into the Earth's magnetic field,the magnetic field first gets squeezed and then the magnetic field lines break and reconnect.
The breaking and reconnecting of the magnetic field lines can cause atomic particles called electrons trapped in the belts to fall into the Earth's atmosphere at the poles. As the electrons fall to the Earth,they collide with gas molecules in the atmosphere,creating flashes of light in the sky. Each atmospheric gas glows a different color. Oxygen and nitrogen glows red and green and nitrogen glows violet-purple. As these various colors glow and dance in the night sky,they create the Northern Lights and the Southern Lights.
Watching auroras is fun and exciting,but normally you can only see them in places far north like Alaska and Canada. The movement of the aurora across the sky is usually slow enough to easily follow with your eyes but they can also pulsate,flicker,or even move like waves.During solar maximum,auroras are seen as far south as Florida,even Mexico!
Auroras often seem to be very close to the ground,but the lowest aurora is still about 100 kilometers above the ground,a distance much higher than clouds are formed or airplanes can fly. A typical aurora band can be thousands of kilometers long,a few hundred kilometers high,but only a few hundred meters thick.
We hope you are able to travel to far north places like the Arctic Circle and see the Northern Lights at least once during your lifetime. We know you will never forget it!
The auroras are formed when the electrons falling into the Earth's atmosphere at the poles and colliding with gas molecules in the atmosphere.
A: Right
B: Wrong
C: Not mentioned
共用题干
Language and Infants
How important is language to young children?Is language,like food,a basic human need without which a child at a critical period of life can be starved and damaged?Judging from the drastic experiment of Frederick Ⅱ in the thirteenth century it may be.Hoping to discover what language a child would speak if he heard no mother tongue he told the nurses to keep silent.
Within the first year,all the infants died.People realized clearly in this case that there was more than deprivation of language._______(46)Without good mothering,in the first year of life especially,the capacity to survive is seriously affected.
Today no such cruel deprivation is allowed to exist that ordered by Frederick.Nevertheless, some children are still backward in speaking. Most often the reason for this is that the mother is insensitive to the cues and signals of the infant,whose brain is programmed to mop up language rapidly.There are critical times,it seems,when children learn more readily._______(47)A bird learns to sing and to fly rapidly at the right time,but the process is slow and hard once the critical stage has passed.
Linguists learn that speech milestones are reached in a fixed sequence and at a constant age, but there are cases where speech has started late in a child who eventually turns out to be of high IQ (Intelligence Quotient).At twelve weeks a baby smiles and utters vowel-like sounds;at twelve months he can speak simple words and understand simple commands;at eighteen months he has a vocabulary of three to fifty words._______(48)
Recent evidence suggests that an infant is born with the capacity to speak.What is special about Man's brain,compared with that of the monkey,is the complex system which enables a child to connect the sight and feel of,say,a teddy-bear with the sound pattern"teddy-bear"._______ (49)
But speech has to be triggered,and this depends on interaction between the mother and the child,where the mother recognizes the cues and signals in the child's babbling,clinging,grasping,crying,smiling,and responds to them._______(50)Sensitivity to the children's non-verbal cues is essential to the growth and development of language.
________（49）
A:At three he knows about 1,000 words which he can put into sentences,and at four his language differs from that of his parents in style rather than grammar.
B:What was missing was good mothering.
C:Lots of information about benefits of baby signing and best ways to go about it can be found.
D:Insensitivity of the mother to these signals dulls the interaction because the child gets discouraged and sends out only the obvious signals.
E:If these sensitive periods are neglected,the ideal time for acquiring skills passes and they might never be learned so easily again.
F:And even more incredible is the young brain's ability to pick out an order in language from the hubbub of sound around him,to analyze,to combine and recombine the parts of a language in novel ways.
