If we planted a lot more trees in just the right places, they could reduce the amount of carbon in the atmosphere to levels not seen since the 1920s, said study leader Jean Francois Bastin, an ecologist from the Swiss Federal Institute of Technology. After examining more than 70,000 high-quality satellite photos of trees from all over the planet, ecologists concluded that the earth could support 900 million additional hectares (公顷) of tree cover.
Bastin and his colleagues developed a computer program that estimates how much forested land could be restored both now and in a future warmer world. The team members combed through 78,774 satellite photos of a variety of ecosystems- everywhere from the thick Amazon rainforest to the dry Sahel in Africa-that had been protected from human influence. They counted every tree in every photo to assess the current tree coverage in natural environments. The researchers combined that information with data about the climate, temperature and soil conditions for each ecosystem. Then they taught their program to put it all together to determine how much tree coverage a particular area could support.
The result shows trees currently cover 2.8 billion hectares of land- but they have the potential to populate as much as 4.4 billion hectares. Right now, much of the additional 1.6 billion hectares is being used for agriculture or urban spaces. The researchers took those areas off the table and saw that the earth still has 900 million hectares ready and waiting to be restored with trees an area roughly the size of Brazil. When those trees mature, they could remove 205 gigatonnes (兆吨) of carbon from the atmosphere, the study calculated, That represents about two-thirds of the roughly 300 gigatonnes of atmospheric carbon that can be traced to human actions, they said.
Even if trees are planted in the most mindful way, other actions are still needed to fight climate change, Bastin said.
1. Why did Bastin develop a computer program?| A．To reduce air pollution in Africa. |
| B．To determine carbon dioxide in the air. |
| C．To assess the potential forested land. |
| D．To calculate the area of forest in the world. |
| A．Looked into. | B．Put away. |
| C．Brought back. | D．Took in. |
| A．Brazil has large areas to plant trees. |
| B．The tree cover is not enough to control greenhouse gases. |
| C．Trees removed two-thirds of carbon in the atmosphere. |
| D．Other actions are equally important compared to planting trees. |
| A．Disapproving. | B．Doubtful. |
| C．Supportive. | D．Objective. |
相似题推荐
【推荐1】When the natural climate changes due to global warming, it can surely affect seals (海豹). The majority of them live in the Antarctic region but the ice is melting and their natural habitat can be seriously affected. These changes don’t take place overnight. They can be the result of many years of additional temperatures in the area. The seals then have to find ways to adapt.
Seals depend on the cool air currents to bring plenty of food for them. When the temperatures get higher there is less and less food and the seal population starts to get depleted. Mothers are not healthy enough to feed their babies. Many of them end up abandoned as the mothers have to leave to find their own source of food.
The fact that their desire to produce young can be changed and the warmer temperature is frightening too. It is also believed that the warmer temperature can allow different diseases and viruses to attack the seals. This is a huge concern as they can rapidly wipe out huge numbers of seals out there.
However, these changes in climate and temperature aren’t all bad for other species of seals. Scientists have found that those living in warmer climates are producing more young due to the changes. Research also shows that the females are moving further to find food and water. When they are out of the reach of the governing males, they are more willing to accept the moves of other males in the group.
This is good news too because it means that there will be more selection in the gene pool (基因库) for future generations. It can help the seals as a species adapt to change in their natural environment more easily.
The climate change problem for seals is directly linked to humans. When we take action to change what we let out into the environment, we will make positive changes for the seals. However, it is going to take a very long time to reverse (彻底改变) the effects of what has already been done.
1. What does the author regard climate changes for seals as?| A．A mirror of evolution. |
| B．A double-edged sword. |
| C．An unavoidable disaster for existence. |
| D．A requirement for more choice in the gene pool. |
| A．Explode. | B．Vary. |
| C．Disappear. | D．Decrease. |
| A．The female seals will be in the lead. |
| B．Their genes will change a great deal. |
| C．Their number will be on the increase. |
| D．The females will keep away from the males. |
| A．How climate change affects seals. | B．The importance of protecting seals. |
| C．Seal’s adaptation to climate change. | D．Why seals are becoming less and less. |
【推荐2】Australia is no stranger to wildfires. The hot and dry weather leads to fires in the wild now and then. However, one that started in September 2019 continued to burn till July 2020, and it might not be natural at all. The fire burned 73,000 square kilometers of land, killing at least 28 people and burning up more than 3,000 homes, reported the Telegraph. Scientists said that man-made climate change played a role in the fire’s creation and duration (持续时间).
According to Australia’s Bureau of Meteorology, the country’s temperatures have risen by more than 1℃ since 1920. The spring of 2019 was Australia’s driest in 120 years. In December, the country saw its hottest day ever, with an average temperature of 41.9 ℃.
“Due to evaporation (蒸发) in warmer temperatures, the plants and the soils dry out more quickly,” Stefan Rahmstorf, an author of the United Nations’ Intergovernmental Panel on Climate Change’s Fourth Assessment Report, told Times.
Even worse, “Wildfires like this might become ‘normal conditions’ in the future,” the researchers at Britain Bureau of Meteorology said to BBC, “We have looked at 57 research papers published since 2013, which examined the relationship between climate change and the risk of wildfires, and have found that the link between the two has already been observed in many parts of the world, including the western US, Canada, southern Europe, and even Siberia.”
“These are effects we are seeing for 1℃ of global climate change. The effects will get worse if we don’t do something with the world’s climate,” Corinne Le Quere, a professor from the University of East Anglia in Britain, told the BBC. “What we are seeing in Australia is not the ‘new normal’. It’s a sign to worse effects. We must take some effective action now. We can’t wait any longer.”
1. From Paragraph 1, what do we know about the wildfire starting last September?| A．It followed the law of nature. | B．It is still burning now. |
| C．It caused the greatest damage. | D．It was related to man. |
| A．More wildfires are likely to break out in the future. |
| B．Any climate change will increase the risk of wildfires. |
| C．Australia is the only country that suffers from wildfires. |
| D．Wildfires will not break out in cold countries or areas. |
| A．The climate in Australia in the future. | B．Solutions to stopping climate change. |
| C．Necessity of fighting climate change. | D．Worse effects of global climate change. |
| A．The effective action we can take. |
| B．Other serious wildfires in Australia. |
| C．Other scientists’ views on global warming. |
| D．More findings about climate change. |
【推荐3】Climate change will increase US wildfires,and the smoky air will cause terrible problems in areas far beyond those burned,reports an environmental group Thursday.
Two-thirds of Americans,or nearly 212 million,lived in states suffering from wildfire smoke three years ago,according to the report by the Natural Resources Defense Council(NRDC).These areas,which had smoke for at least a week,were nearly 50 times greater than those burned directly by fire.
“It affects a much wide area of the United States than people have realized.” says author Kim Knowlton,a Columbia University health professor,adding the smoke can move up to hundreds of miles.She says the smoke contains air pollution and can cause several kinds of diseases.
Texas was hit hardest in 2011,when smoke stayed for at least a week in areas that are home to 25 million people,according to NRDC’s report.Illinois,which recorded no wildfires within its borders, came second with nearly 12 million people affected by smoke that moved in from elsewhere.The other eight states with the most people in touch with smoky air were,in descending order: Florida,Missouri,Georgia,Louisiana,Michigan,Alabama,Oklahoma and Iowa.
Nearly two dozen states had no wildfires within their borders in 2011,but eight of them still had at least one week of smoky air: Illinois,Missouri，Iowa,Kansas,Nebraska,Indiana,Wisconsin and Ohio.
Only 18 states and the District of Columbia had no people in touch with at least a week of smoke that year,although five of them—Alaska,California,Hawaii,Nevada and Utah—had a large area burned by wildfires.
The problem will only get worse.Knowlton says.Scientific research shows climate is causing higher temperatures and health problems.
1. We can learn from the first two paragraphs that_______.| A．climate change killed many Americans |
| B．there are fewer states burned by wildfires |
| C．every state had wildfire smoke for at least a week |
| D．most Americans suffered from wildfire smoke 3 year ago |
| A．Iowa. | B．Kansas. |
| C．Ohio. | D．California. |
| A．going down | B．coming true |
| C．looking practical | D．turning back |
| A．Climate change causes more wildfires. |
| B．Wildfire smoke becomes a serious health problem. |
| C．More wildfires cause climate changes. |
| D．Air pollution becomes a terrible problem. |
【推荐1】Is Your Diet Destroying the Environment?
A vegetarian diet is often praised for its health benefits. Studies have shown that vegetarians usually have lower levels of heart disease and a lower risk of diabetes than people who eat meat. What most people are less aware of, however, are the effects that a vegetarian diet can have on the environment.
Researchers from the Union of Concerned Scientists in the US recently studied how consumer behavior affects the environment. The study showed that meat consumption is one of the main ways that humans can damage the environment, second only to the use of motor vehicle.
Then,how can eating meat have a negative effect on the environment? For a start, all farm animals such as cows, pigs, and sheep give off methane(沼气)gas by expelling(排出)wind from their bodies. One cow can produce up to 60 liters of methane each day. Methane gas is the second most common greenhouse gas after carbon dioxide. Many environmental experts now believe that it is more responsible for global warming than carbon dioxide. It is estimated that 25% of all methane released into the atmosphere comes from farm animals.
Another way that meat production affects the environment is through the use of water and land. 2,500 gallons of water are needed to produce one pound of beef, whereas 20 gallons of water are needed to produce one pound of wheat. One acre of farmland used for crop production can produce 40,000 pounds of potatoes, 30,000 pounds of carrots, or 50,000 pounds of tomatoes.
Many people now see the benefits of switching to a vegetarian diet, not just for health reasons, but also because it plays a vital role in protecting the environment. However, some nutritionists advise against switching to a totally strict vegetarian, or vegan diet. They believe a vegan diet, which excludes all products from animal sources, such as cheese, eggs, and milk, can be short of many necessary vitamins and minerals our bodies need.
Today, many people know it’s important to take better care of their bodies and to use the earth’s resources more efficiently. As this understanding spreads, more people may realize that to help the environment and for the human race to survive, more of us will need to become vegetarians.
1. The underlined word “it” in Para.3 refers to ________.| A．methane gas | B．carbon dioxide |
| C．expelling wind | D．greenhouse gas |
| A．growing tomatoes has the highest production |
| B．crop production is better than meat production |
| C．meat production consumes too much water and land |
| D．farm animals are the main producer of the methane gas |
| A．Doctors suggest switching to totally vegetarian diets. |
| B．It takes more water and land to produce a kilo of crops. |
| C．Farm animals give off methane gas and pollute the environment. |
| D．Carbon dioxide is more responsible for global warming than methane gas. |
| A．Our diet is destroying the surroundings. |
| B．Raising farm animals affects the environment. |
| C．A vegetarian diet helps to protect the environment. |
| D．More and more people are becoming strict vegetarians. |
【推荐2】For years, scientist and others concerned about climate change have been talking about the need for carbon capture and storage(CCS).
That is the term for removing carbon dioxide from, say, a coal-burning power plant’s smokestack and pumping it deep underground to keep it out of the atmosphere, where it would otherwise contribute to global warming.
However, currently, only one power plant in Canada captures and stores carbon on a commercial scale (and it has been having problems). Among the concerns about storage is that carbon dioxide in gaseous or liquid form that is pumped underground might escape back to the atmosphere. So storage sites would have to be monitored, potentially for decades or centuries.
But scientists at Lamont-Doherty Earth Observatory at Columbia University and other institutions have come up with a different way to store CO2 reacts with the rock to form a mineral call calcite(方解石). By turning the gas into stone, scientists can lock it away permanently. Volcanic rocks called basalts(玄武岩) are excellent for his process, because they are rich in calcium, magnesium and iron, which react with CO2.
The project called CarbFix started in Iceland, 2012, when the scientists pumped about 250 tons of carbon dioxide, mixed with water, about 1,500 feet down into porous basalt. Early sings were encouraging: The scientists found that about 95 percent of the carbon dioxide was changed into calcite. And even more importantly, they wrote, the change happened relatively quickly—in less than two years.
“It’s beyond all our expectations,” said Edda Aradottir, who manages the project. Rapid change of the CO2 means that a project would probably have to be monitored for a far shorter time than a more conventional storage site.
There are still concerns about whether the technology will prove useful in the fight against global warming. For one thing, it would have to be scaled up enormously. For another, a lot of water is needed—25 tons of it for every ton of CO2—along with the right kind of rock.
But the researchers say that there is enough porous basaltic rock in Iceland, including in the ocean floors and along the margins of continents. And sitting a storage project in or near the ocean could potentially solve the water problem at the same time, as the researchers say seawater would work just fine.
1. What can we learn about CCS in Paragraphs 2 and 3?| A．Scientists believe global warming will be avoided if CO2 is pumped underground. |
| B．It’s been a common practice in many plants to capture and store CO2 underground. |
| C．There is no guarantee that CO2 will not escape even if pumped underground. |
| D．It requires decades to turn CO2 into liquid form and be locked underground. |
| A．Water, CO2, soda water and basalts |
| B．Water, soda water, a pump and calcite |
| C．CO2, basalts, a pump and calcite |
| D．Water, CO2, a pump and basalts |
| A．it’s disappointing to discover new problems caused by rapid change |
| B．it’s amazing to see 95% of the carbon dioxide turn into calcite that fast |
| C．it’s puzzling to find the encouraging but unexpected result of the project |
| D．it’s exciting to sense the problem of storing CO2 likely to be solved |
| A．To inform us of a breakthrough in storing CO2. |
| B．To praise the efforts of scientists in storing CO2. |
| C．To show the different ways to fight against CO2. |
| D．To urge people to produce the least possible CO2. |
【推荐3】Eco-friendly Vauban, lied in the southwest part of Germany, has everything－tree-lined streets, perfect houses－but it’s missing one urban feature of the last 100 years or so: the car. And Vauban residents(居民) don’t mind one bit. Vauban doesn’t ban cars entirely. Rather, it just tries to reduce the use of cars by creating “parking-free” and “car-free” living. In Vauban, parking spots are a no-no private property(私人财产). Cars can only be parked in public parking lots, so living without a car saves residents the cost of parking in the public lot. Cars also are prevented from using certain roads and must stick to strict speed limits. With these limitations, fewer than 20 percent of residents own cars. Without cars, bikes are almost religion in this small town. Kids pick them up even before they can ride one. Vauban is about much more than just using two wheels instead of four. In Vauban , residents ride bikes and even receive money from the electric company for selling electricity back to the power grid (电网系统). It’s an environmentally-friendly city of the future, with organically grown food, renewable energy, and carbon-neutral homes. And now, with a population of 5,500, it’s attracting attention from around the world. Can an eco-friendly city like Vauban be a model for Americans to stop their over-reliance on the cars?
Sometimes when I watch a news report what’s in the back of my mind is what isn’t being reported or stressed. While this eco-friendly city is inspiring in that it shows residents getting exercise and fresh air through the majority use of bicycles, as well as good old fashioned walking, common sense would tell you that even for a place like Vauban, Germany, it owes its existence to the cars.
Do you think that bicycles were able to transport all the construction materials that were needed to build and maintain the eco-friendly homes and businesses in Vauban? It took cars to help build this utopia. It’s one of the paradoxes of life that sometimes in order to get away from relying on something like the car, you actually have to rely on that very thing at the beginning and into the foreseeable future to some degree.
I myself haven’t owned a car for more than 14 years, and mostly get around town running, walking, or using public transportation. There are times I wish I had one, since it would make many things easier, but overall I’m glad not to have to deal with the headaches of owning a car, which caused me to get rid of it in the first place. And all the walking and running has helped to keep me fit and healthy.
To get even close to being like eco-friendly Vauban, Americans will need to absolutely change the way they live. Commuting( 乘车上下班) patterns will have to change, public transportation will have to be invested in, and so on. And though ending our love affair with the car will be impossible during my lifetime, we may at least start to see more Vauban-like areas in the USA.
We can hope that Americans will consider using their feet more to get around, cutting down on pollution , and giving themselves some more exercise.
1. Why don’t over 80% of the residents in Vauban own car?| A．The streets there are very narrow | B．There are many limitations on the use of cars. |
| C．The government limits the number of cars. | D．Most cars belong to their public property |
| A．opposite things | B．big shortcomings | C．great strengths | D．firm bases |
| A．Curious | B．Proud | C．Grateful | D．Regretful |
【推荐1】Obese people experience discrimination (歧视) in many parts of their lives, and the workplace is no exception. Studies have long shown that obese workers, defined as those with a body-mass index (BMI) of 30 or more, earn significantly less than their slimmer co-workers.
Yet the costs of weight discrimination may be even greater than previously thought. “The overwhelming evidence,” wrote the Institute for employment Studies, “is that it is only women living with obesity who experience the obesity wage penalty (薪资损失).” They were expressing a view that is widely aired in academic papers. To test it, The Economist has analyzed data concerning 23,000 workers from the American Time Use Survey, conducted by the Bureau of Labour Statistics. Our number-processing suggests that, in fact, being obese hurts the earnings of both women and men.
The data we analyzed cover men and women aged between 25 and 54 and in full-time employment. At a general level, it is true that men’s BMIs are unrelated to their wages. But that changes for men with university degrees. For them, obesity is associated with a wage penalty of nearly 8%, even after accounting for the separate effects of age, race, graduate education and marital status.
The conclusion — that well-educated workers in particular are penalized for their weight — holds for both sexes. Moreover, the higher your level of education, the greater the penalty. We found that obese men with a Bachelor’s degree (学士学位) earn 5% less than their thinner colleagues, while those with a Master’s degree earn 14% less. Obese women, it is true, still have it worse: for them, the equivalent figures are 12% and 19%, respectively (分别地).
Your line of work makes a difference, too. When we dealt with the numbers for individual occupations and industries, we found the greatest differences in high-skilled jobs. Obese workers in health care, for example, make 11% less than their slimmer colleagues; those in management roles make roughly 9% less, on average. In sectors such as construction and agriculture, meanwhile, obesity is actually associated with higher wages.
These results suggest that the total costs of wage discrimination borne by overweight workers in America are greater than expected. Now, it’s time for our governments to take it seriously.
1. What does the underlined word “it” refer to in paragraph 2?| A．Obese men earn less salary. |
| B．Only obese women earn less salary. |
| C．Both obese men and women earn less salary. |
| D．Weight discrimination may be greater than previously thought. |
| A．A fat woman office director. |
| B．An obese construction worker. |
| C．An obese man with a bachelor’s degree. |
| D．A heavier female doctor with a Doctor’s degree. |
| A．Supportive | B．Objective | C．Subjective | D．indifferent |
| A．Overweight discrimination in other countries. |
| B．The reason of discriminating obese people in their lives. |
| C．American people’s attitude towards overweight discrimination. |
| D．Actions taken against overweight discrimination in workplaces. |
【推荐2】In 1937, legendary photographer Bradford Wash bum abandoned hundreds of pounds of camera gear(设备), surveying equipment, and supplies when her an into bad weather while exploring Canada’s icy Yukon region.
In late April 2022, professional big-mountain skier Griffin Post set out on a three-week expedition (探险) on to the glacier — located within Canada’s Kluane National Park and Reserve — along with other adventurers and scientists, to hunt down the location of the cameras.
Dora Medrzycka, a University of Ottawa glaciologist, was selected to travel to the site and map out the glacier, to determine where the gear could have moved overtime. A team of glaciologists at the University of Ottawa helped the expedition remotely.
Upon arriving to the region, the team searched on foot, ski, and snowboard. “We had an idea of where to start looking, but nothing very precise,” Medrzycka said, adding, “We covered a lot of kilometers walking up and down the glacier. We couldn’t see it anywhere.
Towards the end of the trip, Medrzycka came up with a new theory about where the items might be located. Glaciers typically move at a constant rate from year to year, but Walsh Glacier is a rare “surging” (急剧上升的) glacier, she said, meaning it moves faster for a year or two every few decades.
She noticed piles of debris (碎片) had traveled the glacier’s entire length, which she believed was caused by the surge. That clued her in on how and when the glacier had flowed in the past.
The observation allowed her to calculate a new estimate of where the items might be, which was three or four miles further down the valley and approximately 14 miles away from the spot where Wash bum had left them. “It was an epic moment for everyone,” Medrzycka said.
Available scientific data on glacial movement only dates back to the 1960s.With this finding, scientists might gain a new understanding of long-term changes to Walsh Glacier.
1. Why did Griffin Post set out for the glacier in late April 2022?| A．To explore Kluane National Park and Reserve. |
| B．To find out the exact position of the cameras. |
| C．To follow the footsteps of Bradford Washburn. |
| D．To learn from other adventurers and scientists. |
| A．Tough but fruitful. | B．Boring but meaningful. |
| C．Attractive and exciting. | D．Stressful and frightening. |
| A．The average rate of glacier movements. |
| B．Precise information about the starting point. |
| C．Technical assistance from the University of Ottawa. |
| D．Medrzycka’s innovative glacial mapping processes. |
| A．The surge of Walsh Glacier dates from the 1960s. |
| B．The flow of Walsh Glacier has stopped since 1960. |
| C．The finding might offer a further insight into glacial movement. |
| D．The finding showed the unchanging landscape of glaciers. |
【推荐3】There is no misery so constant, so upsetting, and so intolerable to others, as that of having a character which is your master. There are corners at every turn in life, against which we may run, and at which we may break out in impatience, if we choose.
Look at Roger Sherman, who rose from a humble occupation to a seat in the first Congress of the United States, and whose judgment was received with great respect by that body of distinguished men. He made himself master of his temper and cultivated it as a great business in life. There are one or two instances which show this part of his character in a light that is beautiful.
One day, after having received his highest honors, he was sitting and reading in his sitting room. A student, in a room close by, held a looking-glass in such a position as to pour the reflected rays of the sun directly in Mr. Sherman’s face. He moved his chair, and the thing was repeated. A third time the chair was moved, but the looking-glass still reflected the sun in his eyes. He laid aside his book, went to the window, and many witnesses of the rude behavior expected to see the ungentlemanly student severely punished. He raised the window gently, and then --- shut the window blind!
I cannot help providing another instance of the power he had acquired over himself. He was naturally possessed of strong passions, but over these he finally obtained an extraordinary control. He became habitually calm and self-possessed. Mr. Sherman was one of those men who are not ashamed to maintain the forms of religion in their families. One morning he called all together as usual to lead them in prayer to God. The “old family Bible” was brought out and laid on the table.
Mr. Sherman took his seat and placed beside him one of his children, a child of his old age. The rest of the family were seated around the room, several of whom were now grown-ups. Besides these, some of the tutors of the college were boarders in the family and were present at the time. His aged mother occupied a corner of the room, opposite the place where the distinguished Judge sat.
At last, he opened the Bible and began to read. The child who was seated beside him made some little disturbance, upon which Mr. Sherman paused and told it to be still. Again he continued but again he had to pause to scold the little offender, whose playful character would scarcely permit it to be still. At this time he gently tapped its ear. The blow, if blow it might be called, caught the attention of his aged mother, who now with some effort rose from the seat and tottered across the room. At last, she reached the chair of Mr. Sherman, and in a moment, most unexpectedly to him, she gave him a blow on the ear with all the force she could gather. “There,” said she, “you strike your child, and I strike mine.”
For a moment, the blood was seen mounting to the face of Mr. Sherman. But it was only for a moment and all was calm and mild as usual. He paused; he raised his glasses; he cast his eye upon his mother; again it fell upon the book from which he had been reading. Not a word escaped him; but again he calmly pursued the service, and soon sought in prayer an ability to set an example before his household which should be worthy of their imitation. Such a victory was worth more than the proudest one ever achieved on the field of battle.
1. The following sentence should be put at the beginning of Paragraph ______.The difference in the happiness which is received by the man who governs his temper and that by the man who does not is dramatic.
| A．One | B．Two | C．Three | D．Four |
| A．By analyzing reasons. | B．By giving examples. |
| C．By listing arguments. | D．By comparing facts. |
| A．He came from a distinguished family background. |
| B．He was not good at displaying his true inner feelings. |
| C．He severely punished a student who didn’t behave himself. |
| D．He was a man conscious of the consequences of his behavior. |
| A．Mr. Sherman’s face was covered with blood. |
| B．Mr. Sherman was seeking strength in prayer. |
| C．Mr. Sherman was then on the point of exploding. |
| D．Mr. Sherman was ashamed of his mother’s rude behavior. |
【推荐1】The brain has a powerful ability to remember and connect events separated in time. And now, in that new study in mice published in Neuron, scientists have cast light on how the brain can form lasting links.
The hippocampus (海马体)—a small, seahorse-shaped region buried deep in the brain—is an important headquarters for learning and memory. “The traditional view has been that cells in the hippocampus keep up a level of continuous activity to associate two events separated by tens of seconds.” said Dr. Ahmed, co-first author of the study. “Turning these cells off would thus disrupt learning.”
To test this view, the researchers imaged parts of the hippocampus of mice as the animals were exposed to two different stimuli(刺激物): a sound followed by a small but unpleasant puff of air. A fifteen-second delay separated the two events. The scientists repeated this experiment across several trials. Over time, the mice learned to associate the sound with the soon-to-follow puff of air. Using advanced microscopy, they recorded the activity of thousands of neurons (神经元), a type of brain cell, in the animals’ hippocampus in each trial for many days.
“We expected to see continuous neural activity that lasted during the fifteen-second gap, an indication of the hippocampus at work linking the sound and the air puff,” said Stefano Fusi, PhD. “But when we began to analyze the data, we saw no such activity.” Instead, the neural activity was sparse. Only a small number of neurons worked, and they did so seemingly at random (随意的).
For further understanding, they had to shift the way they analyzed data and use tools designed to make sense of random processes. Finally, the researchers discovered a complex pattern: a style of mental computing that seems to be a remarkably efficient way that neurons store information.
“We were happy to see that the brain doesn’t maintain ongoing activity over all these seconds because that’s not the most efficient way to store information,” said Dr. Ahmed. “The brain seems to have a more efficient way to build this bridge.”
In addition to helping to map the circuitry (神经回路) involved in associative learning, these findings also provide a starting point to more deeply explore disorders, such as panic and post-traumatic stress disorder.
1. What can we learn about the hippocampus?| A．It helps connect events separated in places. |
| B．It is involved in the visual area of the brain. |
| C．It is a kind of cell buried deep in the brain. |
| D．It is a brain region crucial for memory. |
| A．animals have trouble learning to associate two events |
| B．associations of events require continuous neural activity |
| C．a 15-second delay is enough to separate two events |
| D．disruption of learning turn the activities of cells off |
| A．continuous activity happens as expected |
| B．no neurons stay active at intervals of 15 seconds |
| C．a complex pattern helps the brain learn associations |
| D．neuronal information is stored in well-designed tools |
| A．inspire deeper explorations of disorders |
| B．build a bridge between different parts of the brain |
| C．provide evidence for brain’s ongoing activity |
| D．help map some aspects of a person’s experience |
【推荐2】As each semester begins, my colleague greets his students wearing a jacket and tie.
“You make only one first impression, " he says. So, while the rest of the semester he teaches class in his usual, more casual clothes, the first week he presents a different image.
His thought is that students will remember their encounter positively and more readily think highly of him as the semester goes on because that favorable first impression has an influence on them. The big influence of first impressions is related to the halo effect, where the perception of the positive qualities in one thing or part gives rise to the perception of similar qualities in related things or in the whole.
Here is an example: You meet a friendly person at a party and later are asked to collect money for a worthy cause. You call that person because you think she will make a contribution. In reality, there is no connection between being pleasant and being generous. Yet the halo effect leads you to think that the two are related.
The halo effect is powerful, but is it questionable whether it matters much in long-term relationships, such as that between teachers and students? While dressing up may make students think the teacher must know his subject matter because he creates a professional first impression, the effect wears thin if the person turns out to be a poor teacher after all.
First impressions matter but they don't have the final word. Facts speak louder. If you had never seen or heard of Einstein, the first time you saw him your impression would most likely be negative. Now his face is connected with genius, not madness because he is the person who has come to define what genius is.
The problem is that few of us are Einstein and we often don't get the chance to change a negative first impression.
1. In the author's eyes, the halo effect_________.| A．is surprisingly powerful | B．may affect our judgment of others |
| C．matters more in the long run | D．makes some teachers irresponsible |
| A．appearance | B．impressions | C．truth | D．fairness |
| A．to mind their first impressions | B．not to judge a book by its cover |
| C．not to follow others’ judgment | D．to pay no attention to the halo effect |
【推荐3】If you had asked me then if I would accept a job as a restaurant critic for The New York Times. or any establishment publication, I would have replied, without a second thought, “Of course not!” And not just because I did not want to think of myself as an ambitious sort Working in restaurants was honest labor, anyone could see that. Writing about them for the mainstream press was not; it felt like joining the enemy.
But renewing was fun. so much fun that when mainstream publishers started paying me for my opinions, I didn't do the decent thing. Before I knew it, I had stopped cooking Professionally.
Then I stopped cooking altogether. “She's joined the leisure class.” my friend said.
I disarmed (消解怒气)) my critics by inviting them along; nobody I knew could afford to eat out and nobody refused. We went with equal amounts of guilt and pleasure, with a feeling that we were trespassing (侵入))on the playgrounds of the rich.
We didn't belong in starchy restaurants. We knew it, and when we climbed out of my rent - a - wreck, splendid in years from the Salvation Army, everybody else knew it, too. We always got the worst table. And then, because I didn't own a credit card, I had to pay in cash. The year turned into two and three, and more. I got a credit card. I got good clothes. I was writing for increasingly prestigious (声誉高的)publications. Meanwhile, a voice inside me kept whispering, “How could you?”
The voice is still there, yakking (喋喋不休)away. When I receive weekly letters from people who think it is indecent to write about $100 meals while half the world is hungry, the voice yaks right along, “They're absolutely right, you elitist pig is hisses”. And when it asks. “When are you going to grow up and get a real job?” it sounds a lot like my mother.
And just about then is when I tell the voice to shut up. Because when my mother starts idling me that all I'm doing with my life is telling rich people where to eat, I realize how much the world has changed.
Yes, there are still restaurants where rich people go to remind themselves that they are different from you and me. But there are fewer and fewer of them. As American food has come of age. American restaurants have changed. Going out to eat used to be like going to the opera; today, it is more like going to the movies.
And so everyone has become a critic. I couldn't be happier. The more people pay attention to what and how they eat, the more accustomed they become to their own senses and the world around them.
When I remember that conversation with M. F. K. Fisher, I wish I had not been quite so gentle. When I rerun the loop in my mind, I turn to her and say this: “No, you are wrong. A. J. Liebling had it right. All it really takes to be a restaurant critic is a good appetite.”
1. How did the author feel about the job as a restaurant critic at the very beginning?| A．She didn't think much of it |
| B．She was the ambitious one for it. |
| C．It was not suitable for a cook like her. |
| D．It was not easy to work for the mainstream press. |
| A．A strong desire to be invited to eat out like the rich. |
| B．A mixed feeling of guilt and pleasure about eating out. |
| C．A mixed feeling of guilt and pleasure going into private property. |
| D．A special treat to be able to go into private property for fun. |
| A．She stayed in the career as a cook for years. |
| B．She kept on writing as a restaurant critic for years. |
| C．It was years before she quit the career as a cook. |
| D．It was years before her application for a credit card got approved. |
| A．worthwhile | B．critical | C．unacceptable | D．imperfect |
| A．They have places for both the rich and the poor. |
| B．They have varieties of means for entertainment. |
| C．They have become too expensive to be available. |
| D．They have become affordable to common people, |
| A．The writer is getting tired of the job. |
| B．good appetite makes a good critic. |
| C．There is no need for restaurant critics at all. |
| D．Eating out is no longer a privilege the rich have. |
