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Everyone has those nights-you lie in your bed for hours, tossing and turning, totally unable to fall asleep. You wish you could just turn your brain off as if it were a light. That would make things much easier, wouldn’t it?
Now it looks like you are one step closer to this wild dream of yours-scientists from Oxford University, UK have just discovered the “switch” that tells the brain to go to sleep, reported Forbes.
To understand the study, you first need to know that there are two mechanisms(机能) that regulate sleep. There’s one that we’re already familiar with —our body clock, which works in a 24-hour cycle based on the light changes throughout the day.
The other one is what scientists call the sleep “homeostat(动态平衡系统)”. This mechanism has nothing to do with daylight. Instead, it keeps track of the brain’s waking hours and urges it to rest if it has been awake for a long time. “It is similar to the thermostat(自动调温器) in your home. A thermostat measures temperature and switches on the heating if it’s too cold,” Professor Gero Miesenbock, who led the study, told The Telegraph.
Our bodies use both of the mechanisms to regulate sleep. “The body clock says it’s the right time, and the sleep thermostat has built up pressure during a long waking day,” explained Miesenbock.
There is no way that scientists can trick the body clock. But with the sleep homeostat, there might be something they can do.
The researchers found that the sleep homeostat works by activating a specific group of nerve cells, or neurons, in the brain. They tested their theory on fruit flies by removing the neurons from the insects’ brains. And as expected, they found that the flies without the homeostat neurons did not keep a regular sleep pattern anymore.
Now that scientists have pinpointed the exact place in the brain— or, the “switch”—that regulates sleep, they can begin investigating how to activate these cells at any given time so that people can be sent to sleep instantly.
More importantly, figuring out how sleep mechanisms work may also help us to one day unravel one of the oldest mysteries of all: why do we need to sleep in the first place?
What is the article mainly about?

A.A new way to treat sleep disorders.
B.The discovery of the sleep “homeostat”
C.Advice on what to do when you fail to fall asleep.
D.A comparison of the two mechanisms that regulate sleep.

How does the author explain the function of the sleep homeostat?

A.Through examples.
B.With comparisons.
C.Through cause and effect analysis.
D.By presenting research findings.

What can we conclude from the article?

A.Generally, the sleep homeostat has less effect on people during the day than at night.
B.There is little scientists can do to affect the way the sleep homeostat works.
C.What makes us go to sleep at night is probably a combination of the two mechanisms.
D.The more homeostat neurons there are in one’s brain, the more easily one can fall asleep.

The underlined word “unravel” in the last paragraph is closest in meaning to        .

A.put up with B.figure out
C.keep track of D.take notice of
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【2015·天津】B
Whether in the home or the workplace, social robots are going to become a lot more common in the next few years. Social robots are about to bring technology to the everyday world in a more humanized way, said Cynthia Breazeal, chief scientist at the robot company Jibo.
While household robots today do the normal housework, social robots will be much more like companions than mere tools. For example, these robots will be able to distinguish when someone is happy or sad. This allows them to respond more appropriately to the user.
The Jibo robot, arranged to ship later this year, is designed to be a personalized assistant. You can talk to the robot, ask it questions, and make requests for it to perform different tasks. The robot doesn’t just deliver general answers to questions; it responds based on what it learns about each individual in the household. It can do things such as reminding an elderly family member to take medicine or taking family photos.
Social robots are not just finding their way into the home. They have potential applications in everything from education to health care and are already finding their way into some of these spaces.
Fellow Robots is one company bringing social robots to the market. The company’s “Oshbot” robot is built to assist customers in a store, which can help the customers find items and help guide them to the product’s location in the store. It can also speak different languages and make recommendations for different items based on what the customer is shopping for.
The more interaction the robot has with humans, the more it learns. But Oshbot, like other social robots, is not intended to replace workers, but to work alongside other employees. “We have technologies to train social robots to do things not for us, but with us,” said Breazeal.
How are social robots different from household robots?

A.They can control their emotions.
B.They are more like humans.
C.They do the normal housework.
D.They respond to users more slowly.

What can a Jibo robot do according to Paragraph 3?

A.Communicate with you and perform operations.
B.Answer your questions and make requests.
C.Take your family pictures and deliver milk.
D.Obey your orders and remind you to take pills.

What can Oshbot work as?

A.A language teacher. B.A tour guide.
C.A shop assistant. D.A private nurse.

We can learn from the last paragraph that social robots will ______.

A.train employees B.be our workmates
C.improve technologies D.take the place of workers

What does the passage mainly present?

A.A new design idea of household robots.
B.Marketing strategies for social robots.
C.Information on household robots.
D.An introduction to social robots.

【2015·四川】E
No one is sure how the ancient Egyptians built the pyramids near Cairo. But a new study suggests they used a little rock‘n’roll. Long-ago builders could have attached wooden pole s to the stones and rolled then across the sand, the scientists say.
“Technically, I think what they’re proposing is possible,” physicist Daniel Bonn said.
People have long puzzled over how the Egyptians moved such huge rocks. And there’s no obvious answer. On average, each of the two million big stones weighed about as much as a large pickup truck. The Egyptians somehow moved the stone blocks to the pyramid site from about one kilometer away.
The most popular view is that Egyptian workers slid the blocks along smooth paths. Many scientists suspect workers first would have put the blocks on sleds(滑板). Then they would have dragged them along paths. To make the work easier, workers may have lubricated the paths either with wet clay or with the fat from cattle. Bonn has now tested this idea by building small sleds and dragging heavy objects over sand.
Evidence from the sand supports this idea. Researchers found small amounts of fat, as well as a large amount of stone and the remains of paths.
However, physicist Joseph West thinks there might have been a simpler way , who led the new study . West said , “I was inspired while watching a television program showing how sleds might have helped with pyramid construction . I thought , ‘Why don’t they just try rolling the things?’“A square could be turned into a rough sort of wheel by attaching wooden poles to its sides , he realized . That , he notes , should make a block of stone” a lot easier to roll than a square”.
So he tried it.
He and his students tied some poles to each of four sides of a 30-kilogram stone block. That action turned the block into somewhat a wheel. Then they placed the block on the ground.
They wrapped one end of a rope around the block and pulled. The researchers found they could easily roll the block along different kinds of paths. They calculated that rolling the block required about as much force as moving it along a slippery(滑的)path.
West hasn’t tested his idea on larger blocks, but he thinks rolling has clear advantages over sliding. At least, workers wouldn’t have needed to carry cattle fat or water to smooth the paths.
It’s widely believed that the stone blocks were moved to the pyramid site by ______.

A.rolling them on roads
B.pushing them over the sand
C.sliding them on smooth paths
D.dragging them on some poles

The underlined part “lubricated the paths” in Paragraph 4 means____.

A.made the path wet
B.made the path hard
C.made the path wide
D.made the path slippery

What does the underlined word “it”in Paragraph 7 refer to?

A.Rolling the blocks with poles attached.
B.Rolling the blocks on wooden wheels.
C.Rolling poles to move the blocks.
D.Rolling the blocks with fat.

Why is rolling better than sliding according to West ?

A.Because more force is needed for sliding.
B.Because rolling work can be done by fewer cattle.
C.Because sliding on smooth road is more dangerous.
D.Because less preparation on path is needed for rolling.

What is the text mainly about ?

A.An experiment on ways of moving blocks to the pyramid site.
B.An application of the method of moving blocks to the pyramid site.
C.An argument about different methods of moving blocks to the pyramid site.
D.An introduction to a possible new way of moving blocks to the pyramid site.

【2015·四川】D
Their cheery song brightens many a winter's day. But robins are in danger of wearing themselves out by singing too much. Robins are singing all night一as well as during the day, British-based researchers say.
David Dominoni, of Glasgow University, said that light from street lamps, takeaway signs and homes is affecting the birds' biological clocks, leading to them being wide awake when they should be asleep.
Dr Dominoni, who is putting cameras inside nesting boxes to track sleeping patterns, said lack of sleep could put the birds’ health at risk. His study shows that when robins are exposed to light at night in the lab, it leads to some genes being active at the wrong time of day. And the more birds are exposed to light, the more active they are at night.
He told people at a conference, "There have been a couple of studies suggesting they are increasing their song output at night and during the day they are still singing. Singing is a costly behaviour and it takes energy. So by increasing their song output, there might be some costs of energy."
And it is not just robins that are being kept awake by artificial light. Blackbirds and seagulls are also being more nocturnal. Dr Dominoni said, "In Glasgow where I live, gulls are a serious problem. I have people coming to me saying `You are the bird expert. Can you help us kill these gulls?'.During the breeding(繁殖)season, between April and June, they are very active at night and very noisy and people can't sleep."
Although Dr Dominoni has only studied light pollution, other research concluded that robins living in noisy cities have started to sing at night to make themselves heard over loud noise.
However, some birds thrive(兴旺)in noisy environments. A study from California Polytechnic University found more hummingbirds in areas with heavy industrial machinery. It is thought that they are capitalising on their predators(天敌)fleeing to quieter areas.
According to Dr Dominoni's study, what cause robins to sing so much?

A.The breeding season.
B.The light in modern life
C.The dangerous environment.
D.The noise from heavy machinery.

What is the researchers' concern over the increase of birds' song output?

A.The environment might be polluted.
B.The birds' health might be damaged.
C.The industry cost might be increased.
D.The people's hearing might be affected.

What does the underlined word "nocturnal" in Paragraph 5 mean?

A.Active at night. B.Inactive at night.
C.Active during the day. D.Inactive during the day.

Why do some birds thrive in noisy environments?

A.Because there are fewer dangers.
B.Because there is more food to eat.
C.Because there is less light pollution
D.Because there are more places to take shelter.

【2015·陕西】C
The production of coffee beans is a huge, profitable business, but, unfortunately, full-sun production is taking over the industry and bringing about a lot of damage. The change in how coffee is grown from shade-grown production to full-sun production endangers the very existence of, certain animals and birds, and even disturbs the world’s ecological balance.
On a local level, the damage of the forest required by full-sun fields affects the area’s birds and animals. The shade of the forest trees provides a home for birds and other special(物种) that depend on the trees’ flowers and fruits. Full-sun coffee growers destroy this forest home. As a result, many special are quickly dying out.
On a more global level, the destruction of the rainforest for full-sun coffee fields also threatens(威胁)human life. Medical research often makes use of the forests' plant and animal life, and the destruction of such species could prevent researchers from finding cures for certain diseases. In addition, new coffee-growing techniques are poisoning the water locally, and eventually the world's groundwater.
Both locally and globally, the continued spread of full-sun coffee plantations (种植园)could mean the destruction of the rainforest ecology. The loss of shade trees is already causing a slight change in the world's climate, and studies show that loss of oxygen-giving trees also leads to air pollution and global warming. Moreover, the new growing techniques are contributing to acidic(酸性的) soil conditions.
It is obvious that the way much coffee is grown affects many aspects many aspects of life, from the local environment to the global ecology. But consumers do have a choice. They can purchase shade-grown coffee whenever possible, although at a higher cost. The future health of the planet and mankind is surely worth more than an inexpensive cup of coffee.
What can we learn about full-sun coffee production from Paragraph 4?

A.It limits the spread of new growing techniques.
B.It leads to air pollution and global warming.
C.It slows down the loss of shade trees.
D.It improves local soil conditions.

The purpose of the text is to .

A.entertain B.advertise C.instruct D.persuade

Where does this text probably come from ?

A.An agricultural magazine.
B.A medical journal.
C.An engineering textbook.
D.A tourist guide.

Which of the following shows the structure of the whole text?

【2015·广东】C
Daniel Anderson, a famous psychologist, believes it’s important to distinguish television’s influences on children from those of the family. We tend to blame TV, he says, for problems it doesn’t really cause, overlooking our own roles in shaping children’s minds.
One traditional belief about television is that it reduces a child’s ability to think and to understand the world. While watching TV, children do not merely absorb words and images (影像). Instead, they learn both explicit and hidden meanings from what they see. Actually, children learn early the psychology of characters in TV shows. Furthermore, as many teachers agree, children understand far more when parents watch TV with them, explaining new words and ideas. Yet, most parents use an educational program as a chance to park their kids in front of the set and do something in another room.
Another argument against television is that it replaces reading as a form of entertainment. But according to Anderson, the amount of time spent watching television is not related to reading ability. TV doesn’t take the place of reading for most children; it takes the place of similar sorts of recreation, such as listening to the radio and playing sports. Things like parents’ educational background have a stronger influence on a child’s reading. “A child’s reading ability is best predicted by how much a parent reads.” Anderson says.
Traditional wisdom also has it that heavy television-watching lowers IQ (智商) scores and affects school performance. But here, too, Anderson notes that no studies have proved it. In fact, research suggests that it’s the other way around. “If you’re smart young, you’ll watch less TV when you’re older,” Anderson says. Yet, people of lower IQ tend to be lifelong television viewers.
For years researchers have attempted to show that television is dangerous to children. However, by showing that television promotes none of the dangerous effects as conventionally believed, Anderson suggests that television cannot be condemned without considering other influences.
By watching TV, children learn _________.

A.images through words
B.more than explicit meanings
C.more about images than words
D.little about people’s psychology

An educational program is best watched by a child _________.

A.on his own
B.with other kids
C.with his parents
D.with his teachers

Which of the following is most related to children’s reading ability?

A.Radio-listening
B.Television-watching
C.Parents’ reading list
D.Parents’ educational background

Anderson believed that _________.

A.the more a child watches TV, the smarter he is
B.the younger a child is, the more he watches TV
C.the smarter a child is, the less likely he gets addicted to TV
D.the less a child watches TV, the better he performs at school

What is the main purpose of the passage?

A.To advise on the educational use of TV.
B.To describe TV’s harmful effects on children.
C.To explain traditional views on TV influences.
D.To present Anderson’s unconventional ideas.

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