The most detailed study yet of the physics of a finger snap (响指) has shown that in terms of acceleration (加速度), no other body movement comes close. Using high speed cameras, the researchers found that it reached a speed about 20 times faster than the blink of an eye. This “rotational (旋转的) acceleration” was nearly three times greater than the previous record for humans, set by a professional baseball player's arm.
The research, published in the Journal of the Royal Society Interface, divides the finger snap into three stages. First, force is first built up by pressing the thumb and middle fingers together. This appears to be stored in springlike muscle in the fingers and forearm. Friction (摩擦力) between the two fingers acts like a latch (门闩), preventing the energy from being released. Eventually, an “unlatching” process begins, with the thumb moving sideways and the middle finger quickly sliding past the thumb, starting the snap motion. The middle finger then slips into the palm, generating shockwaves that result in a “pop” sound.
The study was inspired by the Hollywood movie Avengers: Infinity War and the character Thanos, who destroys half the universe by snapping his fingers. He does this while wearing a metal glove. When they saw this scene, Dr Saad Bhamla, the leading researcher, and his colleagues asked themselves if this was possible - could you snap your fingers while wearing a metal glove?
They explored the role of friction by covering fingers with different materials, including metallic thimbles (金属套管), which reduced friction. The researchers concluded that a “Goldilocks zone” of friction was necessary. Too little friction and not enough energy was stored to power the snap. Too much friction led to displacement of energy as the fingers took longer to slide past each other, “wasting” the stored energy as heat. “Our results suggest that Thanos could not have snapped because of his metal armoured fingers. So, it's probably the Hollywood special effects, rather than actual physics, at play,” said Bhamla.
1. What can we learn from paragraph 1?A.The finger snap is the fastest acceleration of our body. |
B.The blink of an eye is faster than a finger snap. |
C.People can have faster acceleration if they want. |
D.Baseball players have the fastest acceleration. |
A.The position of the thumb. | B.The rotational acceleration. |
C.Friction between two fingers. | D.Potential energy from pressing fingers. |
A.They questioned a movie scene. |
B.They suspected the function of fingers. |
C.They wanted to prove a theory in the movie. |
D.They hoped to create different movie scenes. |
A.A finger snap can happen in any movie. |
B.Wearing a metal glove can snap a magic sound. |
C.The finger snap of Thanos in the movie is just a play. |
D.The friction between fingers is occasionally out of control. |
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【推荐1】Like every dog, every disease now seems to have its day. World Tuberculosis (肺结核) Day is on Saturday March 24th.
Tuberculosis was once terribly fashionable. Dying of “consumption” seems to have been a favorite activity of 19th-century artists, which has, however been neglected of late. Researchers in the field never tire of pointing out that TB kills a lot of people According to figures released earlier this week by the World Health Organization, 1.6 million people died of the disease in 2005, compared with about 3m for AIDS and 1m for malaria. But it receives only a fraction of the research budget devoted to AIDS. America’s National Institutes of Health, for example, spends 20 times as much on AIDS as on TB Nevertheless, everyone seems to be getting in on the TB-day act this year.
The Global Fund, an international organization responsible for fighting all three diseases but best known for its work on AIDS, claims that its anti-TB activities since 2002 have saved the lives of over 1m people. The World Health Organization has issued a report that contains some good news. Although the number of TB cases is still rising, the rate of illness is growing only because the population itself is going up.
Even drug companies are involved. Eli Lilly announced a $50m boost to its MDRTB Global Partnership. MDR stands for multi-drug resistance, and it is one of the reasons why TB is back in the spotlight. Careless treatment has caused drug-resistant problems to evolve all over the world. The course of drugs needed to clear the disease completely takes six months, and persuading people to stay that course once their symptoms have gone is hard. Unfortunately, those infected with MDR have to be treated with less effective, more poisonous and more costly drugs.
The other reason TB is back is its relationship to AIDS. AIDS does not kill directly. Rather, HIV weakens the body’s immune system and exposes the sufferer to secondary infections. Of these, TB is one of the most serious. Some anti-TB drugs interfere with the effect of some anti-HIV drugs. Conversely, in about 20% of cases where a patient has both diseases, anti-HIV drugs make the tuberculosis worse. The upshot is that 125 years after human beings worked out what caused TB, it is still a serious threat.
1. What does the first sentence “Like every dog, every disease now seems to have its day.” mean?A.Every dog enjoys good luck or success sooner or later. |
B.Human beings can deal with problems caused by disease. |
C.Tuberculosis becomes a serious infection (感染) disease. |
D.People attach importance to tuberculosis recently. |
A.The US government is reluctant to spend millions of dollars on tuberculosis. |
B.The death rate of AIDS is higher than that of tuberculosis. |
C.The authorities don’t pay much attention to the research of tuberculosis. |
D.Compared with AIDS, tuberculosis can be cured effectively. |
A.Consequence. | B.Reason. | C.Achievement. | D.Project. |
A.Forgive and forget. |
B.Forgotten, but not gone. |
C.When the wound is healed, the pain is forgotten. |
D.Every dog is brave at his own door. |
【推荐2】Aristotle said that “happiness depends upon ourselves” and a new study suggests it is possible to physically grow a happier brain through practices like meditation (冥想). Although scientists have known which hormones (荷尔蒙) produce emotions like pleasure or desire, it has been unclear where the feeling of overall contentment and well-being originates from.
To find out, scientists asked 51 volunteers to rate their own happiness levels and then scanned their brains. Interestingly they discovered that an area of the brain called the precuneus(楔前叶) was larger in people who were happier. It suggests that happiness can be worked like a muscle.
Previous studies have shown that regular meditation can boost grey matter in the precuneus, which could explain why those who meditate report experiencing feelings of general content. The scientists behind the finding said it will now be possible to clinically measure what things make people happier. Researchers believe that the precuneus is particularly important for subjective happiness, such as where someone chooses to make the best of a situation and see it in a more positive light.
Volunteers who scored higher on the happiness surveys had more grey matter mass in the precuneus. In other words, people who feel happiness more intensely, feel sadness less intensely and are more able to find meaning in life have a larger precuneus. “Our results suggest that psychological training that effectively increases grey matter and volume in the precuneus may enhance subjective happiness.” said Dr. Sato.
Speaking about this new research, he also said: “This does not surprise me at all. The brain is easily influenced, just like other organs. Paying attention can literally change your brain.” Prof Dolan, author of the book Happiness By Design, claims that many of the things people believe will make them happy can actually alter their lives in a negative way, “Most things we think will make us happy won’t,” he said. “We’re really always happier if we are focusing on the person we are with and the thing we are doing right now. So make that something you enjoy.”
1. What can we learn from the new study in paragraph 1 ?A.Aristotle’s idea is not quite right. | B.Happiness can be gained physically. |
C.Well-being is from certain hormone. | D.Brains are larger in those who are happier. |
A.It is linked to one’s happiness. | B.It is very important for thinking. |
C.It can be gained from training quickly. | D.It can be found through physical exercise. |
A.Worried. | B.Doubtful. | C.Interested. | D.Optimistic. |
A.Those who meditate less. | B.Those with more physical training. |
C.Those with more grey matter mass. | D.Those who seek more material wealth. |
【推荐3】Emoji might not be your first choice of communication in a disaster, but researchers feel they could make a difference during emergencies, where every second counts. Now, the Emoji-quake campaign is lobbying for an earthquake emoji to be added to the Unicode set — the standard group of icons available on digital devices worldwide. The campaign aims to find an earthquake-appropriate design to be submitted to Unicode.
“Approximately up to one third of the world’s population are exposed to earthquakes,” explains University of Southampton seismologist (地震学家) Dr. Stephen Hicks, a founder of the campaign. “So we really want to be able to communicate to all of those regions, all of those different languages, and an emoji is an amazing way of doing that.”
Unlike many other weather and climate related events, where longer warning times or visible signs are available, earthquakes move incredibly quickly and are difficult to measure while they are still occurring. Populations in areas like Japan and Mexico are dependent on earthquake early warning technology, which issues an alert on digital devices and broadcast media. “You may have seconds to get under a table or to protect yourself,” explains Dr. Hicks. “That can be life saving in many cases. Naturally you don’t want too much wording in the warning message.”
Pictographs (象形文字) and other visuals like emoji have a track record of being faster and easier to understand than written information. Dr. Sara McBride, a communications specialist, who is also part of the campaign, told BBC News, “Emoji can cross the boundaries of written languages, helping communicate valuable information to people who may struggle to read a certain language.”
The potential usefulness of emoji in emergencies could extend well beyond earthquakes. A team of designers also came up with emerji—an entire set of emoji dedicated to climate and environmental events.
1. According to the passage, why did the campaign choose earthquakes as their target?A.Because earthquakes threaten many people in different regions. |
B.Because earthquakes are the easiest to be expressed by an emoji. |
C.Because earthquakes are not difficult to measure while occurring. |
D.Because earthquakes are the most destructive disasters in the world. |
A.Hope for. | B.Enter for. |
C.Appeal for. | D.Run for. |
A.Emoji benefits people with reading disability a lot. |
B.Emoji is being used to convey valuable information. |
C.Emoji can cross the boundaries of written languages. |
D.Emoji is a universal language and helpful tool in communication. |
A.Could an emoji save our life? |
B.What can emoji do in our life? |
C.How is emoji changing our life? |
D.Do we really know about emoji? |
【推荐1】The new year is the moment when people vow to improve their fitness. They join gyms, swear off alcohol and adopt healthier diets. These resolutions usually do not last beyond January.
But some employers try to help their workers stick to their goals by offering “wellness” programmes. One of the longest- running examples began in 1979 at Johnson & Johnson (j&j), an American health-care company.The plan promotes weight loss, smoking quitting and efforts to reduce blood pressure.
The firm claims it reduced medical costs by $400 an employee per year, and resulted in fewer workers suffering from heart disease or high blood pressure. Yet an examination of the data by Martin Cherniack of the University of Connecticut found that in 2005-08, a sharp jump in alcohol use, depression and stress among j&j employees occurred .This coincided with a period when the firm had a target of lifting productivity by 9% a year. So the employees may have been fitter, but it is possible that workplace pressure to produce more meant greater stress.
All this suggests that employee well-being is a rather more complex topic than can be tackled(应对) by a programme devoted to exercise and healthy living. A study by Rand Europe, a research institute, found that obvious bad habits such as smoking and high alcohol use were in fact not associated with lower productivity, while obese workers were no more likely to take time off than anyone else. The biggest productivity problems were associated with lack of sleep, financial concerns and mental-health issues-factors that may well be directly linked to work-related stress.
It seems reasonable for companies to expect some level of economies return on any wellness programme that they provide. But the trade-off should not be too blatant. Making employees fitter so you can work them a lot harder seems rather like drilling your infantry(野战军) on a course before sending them to face the machine guns. A better impact on morale (and thus productivity) might occur if workers felt that their managers had a genuine interest in their welfare.
1. What can we learn from the example of Johnson & Johnson?A.A healthy lifestyle contributes to higher productivity. |
B.A wellness program alone can’t achieve the desired effect. |
C.Caring for employees’ physical health is of great importance. |
D.A health program benefits both the company and the employees. |
A.Certain living habits help improve motivation. |
B.Work-related pressure is to blame for low productivity. |
C.Financial concerns have nothing to do with productivity. |
D.Obesity is associated with lower attendance in the workplace. |
A.Obvious. | B.Effective. | C.Challenging. | D.Flexible. |
A.To compare various factors affecting productivity. |
B.To introduce a new way of increasing productivity. |
C.To appeal to employers to improve their health care program. |
D.To question some seemingly effective practice in business management. |
【推荐2】Welcome to Sight Word Tales-the fun, motivating way to learn sight words! These delightful stories teach the top 100 Dolch words-long recognized as the most important words to learn in order to form a basis for reading success-all in an appealing, engaging context. ① What are sight words? Reading research shows that 50 to 75 percent of text is made up of common, repeated words. Knowing these words by sight-that is, being able to recognize them immediately and without thought-greatly increases reading fluency and comprehension. The Sight Word Tales program includes the 100 most frequently repeated words children are likely to meet in their reading material.
Take a look at these sentences: We like to read. Some books are very good. It's likely that you were able to take in the meaning of each sentence as a whole, simply because words such as we, like, to, some, are, very, and good are so familiar that they hardly require a glance to tell meaning. As adult readers, we may take this lightning-fast process for granted. But to a child who is just beginning to read, these sentences look quite different. Children who need to analyze each letter in order to sound out the words we, like, and to may have already forgotten their meaning by the time they get to the word read. In order to comprehend the sentence, they would then need to go back to the beginning and read it a second time. Now imagine going on to the next sentence and going through the same process all over again. How likely is it that you would remember the first sentence once you'd figured out the second? ②
It's clear that learning sight words-also called high-frequency words-is important to reading success. The ability to recognize a word immediately is called automaticity, and it is particularly important in English because many of the most commonly repeated words do not follow regular phonetic (语音) rules. ③ Of course, phonics is a basic part of any balanced learning program, but words such as come, would, and what cannot be truly made out and therefore require memorization.
Research has shown that only depending on context and exposure to language, hoping children will simply “pick up” sight words at their own pace, is a losing strategy. Sight words must be taught directly. On the other hand, studying and memorizing lists of words is unlikely to engage children.
④ With this program, you get the best of both words-an opportunity to provide direct, targeted instruction while addressing meaning, context, and children's need for fun, all at the same time. So open up a Sight Word Tale and open the door to reading success!
1. “Dolch words” in Paragraph 1 probably refers to ______.A.familiar words | B.high-frequency words | C.reading words | D.long words |
A.To explain why teach sight words. | B.To prove that sight words are familiar. |
C.To compare the meaning of each sentence. | D.To explain why children must read books. |
A.① | B.② | C.③ | D.④ |
A.To teach children reading. | B.To tell children fun stories. |
C.To instruct us to repeat words. | D.To introduce Sight Word Tales. |
【推荐3】Having your nose in a book might seem a little anti-social at times—but reading could actually make you a kinder, more considerate person, a study has found. Readers were more likely to act in a socially acceptable manner, while those who preferred watching television came across as less friendly and less understanding of others’ views, researchers said.
123 participants in the study were quizzed on their preferences for books, TV and plays at Kingston University, London. They were then tested on how much they considered people’s feelings and whether they acted to help others. Researchers told the British Psychological Society conference in Brighton yesterday that fiction fans showed more positive social behavior.
Readers of drama and romance novels were also empathetic, while lovers of experimental books showed the ability to see things from different directions. Comedy fans scored the highest for relating to others. The study suggested reading allows people to see different points of view enabling them to understand others better.
The researchers added, “Exposure to fiction relates to a range of empathetic abilities. Engaging with fictional prose and comedy in particular could be key to improving people’s empathetic abilities.”
However, the authors warned the study did not prove cause-and-effect. So it could be that reading causes positive behavior, or it could be that thoughtful, well-mannered people are more likely to prefer reading. So it is a good idea to pick up a book to begin your travel with the author. Each author will show how they would react to certain situations through their characters. Everyone can view the same situation differently, and from 1,001 different angles. The more you read, the much better you can understand other peoples’ opinions.
1. Why did the writer mention the result of watching television?A.The writer is a anti-social reporter. | B.The writer shows benefits of reading. |
C.The writer is a considerate person. | D.The writer becomes socially acceptable. |
A.The skills of communicating. | B.The time of reading books. |
C.The places of getting new books. | D.The ways of expressing feelings. |
A.Readers of drama. | B.Writers of romance novels. |
C.Readers of comedy. | D.Readers of experiments. |