C
Burning less calories while walking seems like a bad idea, but making the walk easier may actually keep people on their feet longer, and that scientists say, has substantial health benefits.
Analyzing the human walk, biomedical engineers Steven Collins and Greg Sawicki concluded that our ankles and calves perform motions similar to a spring coupled with a clutch that intermittently stores and releases energy.
Sawicki, from the University of North Carolina, explained what’s involved.
“We found in basic science experiments that that system, your calf and Achilles tendon, works a lot like a catapult. So, the muscle holds on to the tendon and your body actually stretches your Achilles tendon quite a bit and then stores the energy in the tissue and then it’s given back to propel you forward in the world,” he said.
Sawicki said he and his colleague Steven Collins at Carnegie Mellon University designed a mechanical device, made of carbon fiber and metal, that performs the same sequence of energy give-and-take outside the body. The system takes over part of the work of walking, and reduces the amount of required energy by as much as seven percent.
Wearing the unpowered ankle exoskeleton can help people either walk farther with the same amount of energy, or restore the normal movement pattern for people who have trouble walking.
Sawicki said it takes only a few minutes to get used to the exoskeleton but the wearer quickly learns to tone down the muscle energy as the device takes over part of the load.
“You really don’t notice it until when you take it off. And when you take it off you realize that it was there and giving you the boost,” he said.
Sawicki added that the device is primarily intended for people recovering from surgery or a stroke. But all persons who spend a lot of time walking, such as police officers or hospital personnel, could benefit from it.
At the moment there are no plans to develop the ankle exoskeleton for the market, but the inventors say some manufacturers have expressed interest.What’s the main idea of the passage?
A.How to reduce energy whiling walking. |
B.Ways to make walking easy. |
C.Introduction to a mechanical device to make walk easier |
D.Guidelines for people recovering from surgery. |
What is true according to the passage ?
A.The device can only benefit people with walking problems. |
B.All people could benefit from it. |
C.With the device, the walkers need seven percent as much as the energy otherwise. |
D.The device can benefit people in the long term. |
What does the underlined word ” propel” mean in paragraph 3?
A.put | B.keep | C.help | D.push |
What can we learn from the last paragraph?
A.The ankle exoskeleton will have a bright future. |
B.The ankle exoskeleton hasn’t appeal to manufacturers. |
C.The ankle exoskeleton will be launched in the market soon. |
D.The ankle exoskeleton will never be produced. |
Last week my youngest son and I visited my father at his new home in Tucson, Arizona. He moved there a few years ago, and I was eager to see his new place and meet his friends.
My earliest memories of my father are a tall, handsome, successful man devoted to his work and his family, but uncomfortable with his children. As a child I loved him. He seemed unhappy with me unless I got straight A’s and unhappy with my boyfriends if their fathers were not as “successful” as he was. Whenever I went out with him on weekends, I used to struggle to think up things to say, feeling on guard.
On the first day of my visit, we went out with one of my father’s friends for lunch at an outdoor café. We talked along that afternoon, did some shopping, ate on the street table, and laughed over my son’s funny facial expressions. Gone was my father’s critical air and strict rules. Who was this person I knew as my father, who seemed so friendly and interesting to be around? What had held him back before?
The next day dad pulled out his childhood pictures and told me quite a few stories about his own childhood. Although our times together became easier over the years, I never felt closer to him at that moment. After so many years, I’m at last seeing anot
her side of my father. And in so doing, I’m delighted with my new friend. My dad, in his new home in Arizona, is back to me from where he was.
Why did the author feel bitter about her father as a young adult?
A.He was silent most of the time. | B.He was too proud of himself. |
C.He did not love his children. | D.He expected too much of her. |
When the author went out with her father on weekend, she would feel .
A.nervous | B.sorry | C.tired | D.safe |
What does the author think of her father after her visit to Tucson?
A.More critical. | B.More talkative. |
C.Gentle and friendly. | D.Strict and hard-working. |
The underlined words “my new friend” in the last paragraph refer to.
A.the author’s son | B.the author’s father |
C.the friend of the author’s father | D.the café owner |
Ears are for hearing — everyone knows that. But for a creature called the Cuvier’s beaked whale, hearing starts in the throat (喉咙), a new study found.
The observation might help explain how all whales hear. The work might also help scientists understand how animals are affected by underwater sonar (声呐). This sonar, used by some ships, sends out sound waves to locate underwater objects.
The Cuvier’s beaked whale is a so-called toothed whale. Toothed whales dive deep into the ocean in search of food. As the whales hunt, they produce sounds that reach objects and then return to the whales. This allows the animals to “see” the shape, size, and location of objects, even when they’re 1,000 meters under the sea, where it is totally dark.
To better understand how the whale hears, researchers from San Diego State University in California took X rays of two Cuvier’s beaked whales. The whales had died and washed up on the beach.
Ted Cranford and his colleagues used the images to make a computer model of a Cuvier’s beaked whale’s head. Then, they modeled the process of sound traveling through the head.
The researchers knew that some sounds get to the ears of a toothed whale through a structure (构造) called “the window for sound”. Found on the lower jaw, this structure is very thin on the outside and has a large pad (垫) of fat on the inside.
When the researchers used their computer model to work out how sound waves travel in the whale’s head, they were surprised to find that sounds coming from right in front of the whale actually travel under the animal’s jaw. From there, sound waves move through the throat, into a hole in the back of the jaw, and finally to the pad of fat near the animal’s ears. Toothed whales look for food under the sea by ______.
A.watching the shape and size of their objects | B.diving deep into the sea |
C.sending and receiving sounds | D.making lots of noises |
Researchers took X rays of two Cuvier’s beaked whales in order to ______.
A.find out why they had died and washed up on the beach |
B.make a computer model of a Cuvier’s beaked whale’s head |
C.make sure that sound travels through the head |
D.know more about the way the whale hears |
Which of the following describes the way taken by sound waves through a Cuvier’s beaked whale?
A.A hole in the back of the jaw → the ears → the jaw → the throat. |
B.The jaw → the throat → a hole in the back of the jaw → the ears. |
C.The throat → the jaw → the ears → a hole in the back of the jaw. |
D.The ears → the throat → a hole in the back of the jaw → the jaw. |
Which of the following is TRUE according to this passage?
A.The throat is important to the Cuvier’s beaked whale’s hearing. |
B.Ships send out sound waves like a Cuvier’s beaked whale. |
C.The ears are actually useless to the Cuvier’s beaked whale. |
D.The researchers haven’t found how the whales hear. |
A scientist who developed a way to calculate how much water is used in the production of anything from a cup of coffee to a hamburger was awarded the 2008 Stockholm Water Prize.
Professor John Anthony Allan of the University of London in Britain won the award for introducing the idea of “virtual water (虚拟水)”, a calculation method that has changed the nature of trade policy and research.
Allan has written seven books and published more than 100 papers.
The Stockholm International Water Institute said this idea is now embedded (埋藏) in the production of foods and industrial products. The institute said Allan’s work had made a big effect on global trade policy and research, especially in water-scarce (缺水的) regions.
“The improved understanding of trade and water management issues on local, regional and global scales are of the highest value for the successful and sustainable (可持续的) use of water resources,” it said.
“People do not only use water when they drink it or take a shower,” the institute said. “Behind the morning cup of coffee, there are 140 liters of water that was used to grow, produce, package and ship the beans.” That is about as much water as a person in England uses on average for all daily drinking and household needs.
“For a single hamburger, about 2,400 liters of water are needed. In the USA, the average person uses nearly 7,000 liters of virtual water every day.” It said that was more than three times the average use of a Chinese person.Allan was awarded the prize because _______.
A.he wrote seven books on trade policy |
B.he published more than 100 papers on water management |
C.he found a new kind of water in water-scarce areas |
D.he came up with the idea of virtual water |
Which of the following is TRUE according to the passage?
A.The average American uses about 7,000 liters of water a day. |
B.The average Chinese uses nearly 2,300 liters of virtual water a day. |
C.An Englishman usually drinks about 140 liters of coffee a day. |
D.A hamburger usually contains about 2,400 liters of water. |
What do we learn about John Anthony Allan from the passage?
A. He won the 2008 Nobel Prize. B. He has written over 100 books.
C. He works at the University of London. D. He lives in the USA.What effect does the idea of virtual water have?
A.It helps us realize the importance of trade. |
B.It helps people do successful business. |
C.It helps us make use of water scientifically. |
D.It tells us how much water we use a day. |
The manager and staff are happy to welcome you and will do all they can to make your stay an enjoyable one.
MEAL TIMES
Our overnight charge includes a continental-type breakfast.
Breakfast: 7:30—9:30 a. m.
Lunch: 12:00—2:00 p. m.
Afternoon tea: 4:00—5:30 p. m.
Dinner: 7:00—9:15 p. m.
Meals can be served in rooms at a small extra charge. We regret that meals can not be served outside these times.
Light refreshments(茶点) including tea, coffee, biscuits and sandwiches can be served in rooms between 10:00 a.m. and 11:00 p.m. except during the meal times listed above. Cold drinks are available in the room refrigerator.
ROOM CLEANING
Please hang the sign on your door handle if you do not wish to be disturbed. It will be easier for the maids if you can leave the room temporarily(暂时地) at any time between 9:00 a.m. and 4:00 p.m.
VALUABLES
We are not responsible for the loss of money, jewels, or other valuables unless they are kept in the safe and signed for by the manager.
DEPARTURES
Please inform receptionists(接待员) of your intended leaving before 9:30 a. m. of the day concerned and leave the room by noon to allow for its preparation for incoming guests. If necessary, luggage can be left in the charge of the hall porter(搬运工人)。
A SPECIAL REQUEST
We would respectfully suggest that in consideration of the comfort of other guests, the volume of radios and televisions should be turned down after 11:00 p. m. .Meals can be served.
A.in rooms at 9:00 p.m. | B.in the dining room from 7:30 a. m. to 9:15 p. m. |
C.in the dining room at 6:00 p. m. | D.outside the room at 3:00 p. m. |
If you intend to leave the room tomorrow, you may leave at any of the following hours EXCEPT .
A.10:00 a. m. | B.12:00 a. m. | C.3:00 p. m. | D.11:00 a. m. |
Which of the following statements is NOT true?
A.Cold drinks can be found in the room refrigerator. |
B.Guests are requested to turn down their radios and televisions after 11:00 p. m. |
C.The sign that can be hung on the door handle shows that the room needs to be cleaned. |
D.Your luggage can be kept by the hall porter. |
Where is this notice most likely to be found?
A.In hotels. | B.In the newspapers. | C.At restaurants. | D.In shops. |
Everyone knows that the French are romantic, the Italian are fashionable and the Germans are serious. Or do they? Are these just stereotypes or is there really such a thing as national character? And if there is, can it affect how a nation succeed or fail?
At least one group of people is certain that it can. A recent survey of the top 500 entrepreneurs (实业家) in the UK found that 70 percent felt that their efforts were not appreciated by the British public .
Britain is hostile to success, they said. It has a culture of jealousy (嫉妒) . As a result, the survey said, entrepreneurs were “unloved, unwanted and misunderstood”. Jealousy is sometimes known as the “green-eyed monster” and the UK is its home. Scientists at Warwich University in the UK recently tested this idea. They gathered a group of people together and gave each an imaginary amount of money. Some were given a little, others a great deal. Those given a little money were given the chance to destroy the large amounts of money given to others—but at the cost of losing their own. Two thirds of the people tested agreed to do this.
This seems to prove the entrepreneurs were right to complain. But there is also conflicting evidence. The Organization for Economic Cooperation and Development (OECD) recently reported that the UK was now the world’s fourth largest economy .That is not bad for people who are supposed to hate success. People in the UK also work longer hours than anyone else in Europe. So the British people are not lazy , either .
“It’s not really success that the British dislike,” says Carey Cooper, a Professor of management at the University of Manchester Institute of Science and Technology. “It’s people using their success in a way that seems arrogant (傲慢) or unfair or which separates them from their roots .”
Perhaps it is the entrepreneurs who are the problem. They set out to do things in their way. They work long hours. By their own efforts they become millionaires. But instead of being happy they complain that nobody loves them. It hardly seems worth following their example. If they were more friendly, people would like them more. And more people want to be like them.What does the underlined “it” in the second paragraph refer to?
A.One group of people | B.A great survey |
C.National character | D.A nation |
Most entrepreneurs surveyed believe that
A.they are not popular simply because they are successful |
B.the British public are hardworking |
C.love of success is Britain’s national character |
D.they are considered as “green-eyed monsters” |
What does the result of the Warwich University test show?
A.Two thirds of the people tested didn’t love money |
B.Most people would rather fail than see others succeed |
C.An imaginary amount of money does not attract people |
D.Most people are willing to enjoy success with others |
The writer of the passage seems to suggest that .
A.Jealousy is Brit![]() |
B.British entrepreneurs are not fairly treated |
C.the scientists are Warwich University did a successful test |
D.the British dislike the entrepreneurs because they do not behave properly |