When you walk with a backpack, do you know how the things inside move from side to side? Now scientists have figured out how to tap into that movement to produce electricity.
Picture a pendulum(摆锤) fixed to a backpack frame and stabilized with springs on either side. The pack’s weight is attached to the pendulum, so the pendulum swings side to side as you walk. Then a machine is driven by that swinging movement, and produces electrical current to charge a battery.
Volunteers carried the pack while walking on a running machine and wore masks to measure the flow of O2 and CO2. When the volunteers were walking with the slightly swinging 20-pound load, the device did not significantly affect their metabolic(新陈代谢的) rate compared to when they carried the same weight fixed in place. In fact, the energy-harvesting pack reduced the forces of acceleration they’d feel in a regular pack, which might mean greater comfort for a long hike. And the device did produce a steady trickle(涓流) of electricity. If you up the load to 45 pounds, it could fully charge a smartphone only after 12 hours. The details are in the journal Royal Society Open Science.
The device produces electricity from human movement and has been identified as a workable solution to providing a renewable energy source for portable electronic devices. It is particularly useful to those who work in remote areas, as these people often carry a lot of weight in a backpack for their exploration.
But here’s a real conundrum: the energy-harvesting device currently weighs five pounds. The researchers say that’s about four pounds too many to be a smart alternative to batteries. So they hope that more research lets them lighten the load so that they can ensure the pack charges your phone up without weighing you down.
1. What does Paragraph 2 mainly talk about?| A．How the device works. | B．What the device looks like. |
| C．Who the device is designed for. | D．Why scientists designed the device. |
| A．It was useless for a long walk. |
| B．It failed to produce steady electricity. |
| C．It harvested energy as the volunteers walked. |
| D．Royal Society Open Service conducted the study of the device. |
| A．bond. | B．problem. | C．decision. | D．method. |
| A．Finding Smarter Alternatives to Batteries | B．How Can the Movement of Backpack Help? |
| C．Charging Batteries When Carrying Backpacks | D．Searching for New Ways to Charge Your Phone |
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【推荐1】It's hard for doctors to do a thorough eye exam on small children. But a new smartphone app takes advantage of parents' fondness for taking pictures of their children to look for signs that a child might be developing an eye disease.
The app is the result of a father's five-year quest to find a way to catch the earliest signs of eye diseases, and prevent loss of vision. Five years ago, doctors diagnosed (诊断）Noah Shaw's retinoblastoma—a rare type of eye cancer—when he was 4 months old. To make the diagnosis, the doctors shined a light into Noah's eye, and got a pale reflection from the back of the eyeball, an indication that there was something wrong there. Noah's father Bryan, a scientist, wondered if he could see that same pale reflection in pictures of his baby son. Sure enough, he saw the reflection, which doctors call "white eye", in a picture taken right after Noah was born.
Then Bryan decided to create an app that could scan photos for signs of this reflection. Now, that app exists, called CRADLE. To test the app, Bryan and his colleagues analyzed more than 50, 000 pictures taken of 40 children. Half had no eye disease and half had. "On average, the app detected 'white eye' in pictures collected 1. 3 years before diagnosis," says Bryan.
The app isn't perfect. It sometimes misses "white eye" when it's there, and sometimes says it's there when it's not. That latter condition is a problem. Even though the so-called false positive occurs less than 1% of the time, that's not good enough. There are about 4 million children born in the U. S. each year. A 1% false positive rate would mean tens of thousands of children showing up at the doctor unnecessarily.
Still, Bryan is upbeat about the promise of the app. "This is exciting new technology, and this is how I think we're going to go about screening for a number of diseases in the future," he says.
1. What inspired Bryan to create CRADLE?| A．His son's diagnosis. |
| B．His family photos. |
| C．His hobby of taking pictures. |
| D．His working experience as a scientist. |
| A．lt is a sign of some eye diseases. |
| B．It hardly causes serious loss of vision. |
| C．It refers to the white part of an eyeball. |
| D．It occurs when no light is reflected from the eye. |
| A．It may delay the treatment of a patient. |
| B．It may badly affect the future of the app. |
| C．It may raise serious doubts about doctors. |
| D．It may cause a waste of medical resources. |
| A．Curious. | B．Cautious. |
| C．Optimistic. | D．Worried. |
【推荐2】A tracked robot approaches a pile of brushwood blocking its path. This is Rolan, short for Robot Manipulator (操控者), who is practising for what is its graduation ceremony, when it will show off its skills. After a pause, it reaches out an arm, takes hold of a branch, lifts it up and drags it clear.
Though this is a small action for a human being, it is a breakthrough for robots, according to Stuart Young of the Army Research Laboratory, who is in charge of the RoMan project. As is known, robots easily become confused by something unexpected, some unfamiliar and none with convenient handles. Taking it apart is far beyond the power of any industrial robot. Dr. Young says that, as far as he knows, RoMan is the first machine able to manipulate unfamiliar objects in an unknown environment.
Just as a human being would, it has to learn about the world through observation and experiment before manipulating it. So it is trained on numerous tree branches until it is able to recognize unfamiliar ones for what they are and knows to grasp the trunk, rather than the leaves or the branches. Having grasped an object, RoMan assesses its weight and decides whether to try to lift it or drag it.
Dr. Young hopes to take this further by dealing with piles of burning tyres. He also wants RoMan to be able to use its body weight in the way a human being might to push open a tight door or to move heavy furniture by bracing against a wall. One problem with RoMan is that it is still impractically slow. It often takes 10-15 seconds to decide what to do. RoMan will also need to learn to deal with a wider range of objects.
However, the device's future could be bright. Beyond military applications, its following generations might work in warehouses, pick fruit, clear litter or tidy people's homes. They might even collect rocks from the surface of Mars.
1. Why does RoMan take a pause before taking action?| A．The branch is too heavy for it. |
| B．It is reflecting on its next move. |
| C．It takes time to show off its skills. |
| D．It is totally confused by the mess. |
| A．Everything existing around. |
| B．Observation before manipulating. |
| C．The similarity to a human being. |
| D．RoMan's ability acquired by training. |
| A．The author's wish for RoMan. | B．The power of RoMan's weight. |
| C．Dr.Young's regret for RoMan. | D．RoMan's room for improvement. |
| A．Sports&Entertainment. | B．Health&Medicine. |
| C．Education&Career. | D．Science&Technology. |
In Califormia, another interesting kitchen robot has been developed, called Readybot. It can pick up objects and either srore them in cabinets (橱柜）or put them in the trash. It also carries a separate floor-cleaning robot that can operate by itself.Unlike the Japanse robot,Readybot just looks more like a large box with arms and wheels.
Readybot was created by engineers and designers who who etablished a called the Readybot Challlenge. They believe that in the future millions of robots will be needed in homes to perform ordinary household tasks. Readybot is just the step in their plan to create a robot that can do jobs not only in kitchens but in other rooms of homes and in offces as well.
Clearly there are tcchnogical difficulties to to solve before robots can cook a Complete dinner, and there are diso many safety concerns (忧虑） .Not everyone (especially parents) would be comfortable with the idea of robots in their house, manipulating hot pans and sharp knives. The European Commission recently furtded(资助） a project to study these concerns. According to lead researcher Professor Chris Melhuish,“ Enabling robots to work safely with humans is a key need for the future developmem of
robots.”
1. Compared with Readybot, which of the following is true about the Japanese robot?
| A．It is more popular. |
| B．It performs more jobs, |
| C．It moves inore quickly. |
| D．It looks more like a person. |
| A．drive you around |
| B．clean your kitchen |
| C．prepare food for you |
| D．work for office workers |
| A．Inventing |
| B．Avoiding. |
| C．Controlling. |
| D．Making. |
【推荐1】Biology may not be everything, but genes apparently have a far greater influence on human behavior than is commonly thought. Similarities ranging from hobbies to bodily gesture are being found in pairs separated at birth. Many of these behaviors are “things you would never think of looking at if you were going to study the genetics of behavior,” says psychologist Thomas J. Bouchard, Jr. , director of the Minnesota Center for Twin and Adoption Research at the University of Minnesota.
Bouchard reports that so far, exhaustive psychological tests and questionnaires have been completed with approximately 50 pairs of identical twins reared apart, 25 pairs of fraternal twins reared apart and comparison groups of twins reared together. “We were amazed at the similarity in posture and expressive style,” says Bouchard. “It’s probably the feature of the study that’s grabbed us the most.” Twins tend to have similar mannerisms, gestures, speed and tempo in talking, habits and jokes. Many of the twins dressed in similar fashion--one male pair who had never previously met arrived in England sporting identical beards, haircuts, glasses and shirts.
The most striking example of common psychopathology (精神病理学) however, came from a pair of twins raised apart. One had been reared by his own (poor) family the other had been adopted into a “good solid upper-middle-class family.” Both are now considered to be antisocial personalities, suffering from lack of impulse control, and both have criminal histories. Although the twins share, on average, 50 percent of their genes, Bouchard suggests that the overlap is probably considerably more with this pair.
Personality similarities between the identical twins raised apart are almost the same as they are with identical twins raised together, according to the results of a test developed by University of Minnesota psychologist Auke Tellegen. His personality questionnaire contains scales such as “social closeness,” “harm avoidance” and “well-being.” The researchers were especially surprised to find that “traditionalism” — a trait implying conservatism and respect for authority — can be inherited. In fact, says Bouchard, his and other studies have found about 11 personality traits that appear to have significant genetic input.
Overall, the emerging findings of the Minnesota study constitute a powerful disproof of those who maintain that environmental influences are the primary shaping forces of personality. The textbooks are going to have to be rewritten, Bouchard predicts.
1. Why does Bouchard say these behaviors are “things you would never think of looking at if you were going to study the genetics of behavior?”| A．These behaviors seemed too unimportant for scientists to observe. |
| B．These behaviors seemed too intimate to allow scientists to observe them. |
| C．Psychologists assumed these external characteristics could not be biologically based. |
| D．Psychologists assumed the causes of these behaviors were too complicated for current methods of observations. |
| A．fashionable | B．alike | C．complex | D．identified |
| A．some textbooks on genes and behavior will be rewritten quite soon. |
| B．people’s behaviors and personalities depend at large on their genes |
| C．his personality questionnaire can indicate people’s 11 personality traits |
| D．the environmental influences have great effect on people’s personalities |
| A．Twins generally share the same hobbies and gestures if they are raised apart. |
| B．Genes have a greater influence on human behavior than is commonly thought. |
| C．People from upper-middle-class family are the same as those from poor family. |
| D．Twins tend to dress in similar fashion even when brought up in different families. |
【推荐2】Curiosity is what drives us to keep learning, keep trying, keep pushing forward. But how does one generate (产生) curiosity, in oneself or others? George Loewenstein, a professor of psychology at Carnegie Mellon University, offered an answer in the classic1994 paper, “The Psychology of Curiosity.”
Curiosity arises, Loewenstein wrote, “when attention becomes focused on a gap in one's knowledge. Such information gaps produce the feeling of deprivation (匮乏) labeled curiosity. The curious individual is motivated to obtain the missing information to reduce the feeling of deprivation.” Loewenstein's theory helps explain why curiosity is such a force: it's not only a mental state but also an emotion, a powerful feeling that drives us forward.
Scientist Daniel Willingham notes that teachers are often “so eager to get to the answer that we do not devote enough time to developing the question.” Yet it's the question that stimulates (刺激) curiosity; being told an answer stops curiosity before it can even get going.
In his 1994 paper, George Loewenstein noted that curiosity requires some basic knowledge. We're not curious about something we know absolutely nothing about. But as soon as we know even a little bit, our curiosity is aroused and we want to learn more. In fact, research shows that curiosity increases with knowledge: the more we know, the more we want to know. To get this process started, Loewenstein suggests, take steps with some interesting but incomplete information.
Language teachers have long used communication in exercises that open an information gap and then require learners to communicate with each other in order to fill it. For example, one student might be given a series of pictures for the beginning of the story, while the student's partner is given a series of pictures showing how that same story ends. Only by speaking with each other (in the foreign language they are learning, of course) can the students fill in each others' information gaps.
1. When one notices a gap in his knowledge, he .| A．desires to fill it |
| B．tends to be afraid |
| C．might get tired and sad |
| D．will become focused on his learning |
| A．Answers are more important than questions. |
| B．Teachers should be eager to get to the answer. |
| C．Teachers know how to stimulate students’ curiosity. |
| D．Teachers are partly to blame for students’ hating school. |
| A．have read a lot of books | B．know little about something |
| C．have some related information | D．are given incomplete information |
| A．Why students hate school. |
| B．Why curiosity is important. |
| C．How to stimulate curiosity. |
| D．What makes people hungry for knowledge. |
【推荐3】The remains of a gold mask were found at an archaeological site in China's Sichuan province in March 2021. Weighing about 280 grams and estimated to be made from 84% gold, the mask was one of over 500 items unearthed from six newly discovered sacrificial pits（坑）, according to the country's National Cultural Heritage Administration.
The finds were made at Sanxingdui, a 4.6-square-mile area outside the provincial capital of Chengdu. Some experts say the items may shine further light on the ancient Shu state, a kingdom that ruled in the western Sichuan basin until it was conquered in 316 BC.
In addition to the gold mask, archaeologists uncovered golds and artifacts（手工艺品）made from ivory and bone. The six pits, of which the largest has a footprint of 19 square meters, also yielded an as-yet-unopened wooden box.
More than 50,000 ancient artifacts have been found at Sanxingdui since the 1920s, when a local farmer accidentally came upon a number of relics at the site. A major breakthrough occurred in 1986, with the discovery of two pits containing over 1,000 items.
A third pit was then found in late 2019, which led to the discovery of a further five last year. Experts believe the pits were used for sacrificial purposes, explaining why many of the items contained were burned as they were dropped in and buried.
Sanxingdui is believed to have sat at the heart of the Shu state, which historians know relatively little about due to a shortage of written records. The site has revolutionized experts' understanding of how civilization developed in ancient China. In particular, evidence of a unique Shu culture suggests that the kingdom developed independently of neighboring societies in the Yellow River Valley, which was traditionally considered to be the cradle（摇篮）of Chinese civilization.
1. Why are the remains of a gold mask mentioned in paragraph 1?| A．To lead in the topic of the text. |
| B．To stress the importance of gold. |
| C．To show the symbolic meaning of gold. |
| D．To praise the skills of ancient Shu state. |
| A．3. | B．8. |
| C．9. | D．14. |
| A．promoted | B．strengthened |
| C．weakened | D．updated |
| A．A Complete Gold Mask Unearthed in Sichuan |
| B．The History of China's Ancient Shu State |
| C．Another Great Discovery in Sanxingdui |
| D．Mystery of Sanxingdui Solved in 2021 |
