Mosquitoes can spread a range of potentially life-threatening diseases. Existing methods of controlling the insect can be inefficient. For example, mosquitoes can develop a resistance to insecticides(杀虫剂).
Now, Kevin Gorman at the biotechnology firm Oxitec in Abingdon, UK, and his colleagues have genetically modified (基因改造) males of the mosquito species Aedes aegypti in a way that will greatly cut the insect’s population. Among all mosquito species, only females bite. So the team modified males to create so-called OX5034 mosquitoes. They have a gene that allows young male mosquitoes to live, but prevents the females from surviving into adulthood.
In the peak season for reproducing, OX5034 males were released into four heavily populated places in the city of Indaiatuba in Brazil. Within two of these neighborhoods, 100 modified mosquitoes were released at a time, while the remaining test areas were exposed to up to 500 of the insects at a time. Compared with a nearby community that wasn’t exposed to any of these mosquitoes, the places where the modified insects were released saw an 88 percent to 96 percent decline in their mosquito population.
The researchers particularly focus on controlling dengue-a disease caused by a virus carried by mosquitoes. Globally, the number of dengue cases has grown significantly in the past three decades, with 100 million to 400 million cases now occurring annually. While the study didn’t look at whether suppressing (抑制) the mosquitoes led to a lower rate of dengue, there was evidence of this elsewhere. Similar efforts in Australia saw fewer cases of locally spread dengue compared with previous years. A study also found a 77 percent reduction of dengue in Indonesia after modified mosquitoes were introduced there.
According to Dawn Wesson at the Tulane University School of Public Health and Tropical Medicine, Louisiana, Oxitec’s effort is a step up from previous insect control strategies in which mosquito sexual selection wasn’t done by genetic means. That’s the beauty of this method. As well as dengue, Oxitec is making plans for developing modified mosquitoes to reduce other diseases like malaria, says Nathan Rose at Oxitec.
1. How does Kevin Gorman’s team try to control mosquitoes?| A．By decreasing the males’ population. |
| B．By transforming all mosquitoes’ genes. |
| C．By shortening the females’ life. |
| D．By improving the insecticides’ effect. |
| A．The target and site. | B．The process and findings. |
| C．The data and report. | D．The preparations and methods. |
| A．To state the potential use of the method. |
| B．To explain the background of the study. |
| C．To draw attention to the severity of dengue. |
| D．To show the method’s effect on reducing dengue. |
| A．Widening the applications of the method. |
| B．Engineering other species of mosquitoes. |
| C．Exploring better mosquito control strategies. |
| D．Finding cures for mosquito-related diseases. |
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【推荐1】The beautiful island country of Madagascar has a serious school shortage. About a third of Malagasy children have no access to education because the schools are too far away or severely overcrowded. Thinking Hus, a non-profit dedicated to increasing global access to education, plans to tackle the issue with a series of 3D-printed schools, the first of which was completed in April 2022.
The 765-square-feet structure, named Bougainvillea, will house 30 students. The construction a began with the printer pouring a cement-like (水泥状) mixture in a pattern to create the walls. The entire process took just 18 hours! The roof, doors and windows were locally sourced, and the walls were made of a cement mixture that can resist big environmental pressures in the area. Bougainvillea was 3D printed by 14 Trees, a company with experience printing buildings throughout Kenya and Malawi.
Maggie Grouts, the 22-year-old founder of Thinking Huts, is a senior at the University of Colorado and was just 15 when she started Thinking Huts. Adopted from a rural village in China when she was 18 months old, Grout realized that not all kids were as fortunate as her and wanted to help. The idea for the 3D-printed schools came to her after brainstorming(集思广益) with her father on ways to use the technology for the greater good.
The 3D printing approach shrinks the construction turnaround time from months to days, as well as the cost. This allows more schools to be built in less time and reduces the building’s carbon footprints. And these savings in time, cost and materials meet a real need for education infrastructure (基础设施) to help bridge the global opportunity gap.
“Thinking Huts hopes to have a Thinking Hut in every community where children do not have a place for education and is fundraising to develop this goal. By using 3D printing, we are combining the potential of technology with architectural solutions that tackle real problems the world faces within education,” says Grouts.
1. What are 3D-printed schools intended for?| A．Reducing construction wastes. |
| B．Providing high-quality education for local students. |
| C．Helping deal with a shortage of schools. |
| D．Drawing public attention to 3D-printing technology. |
| A．It has a complex architectural structure. |
| B．It features strong resistance to bad weather. |
| C．It is built with the help of the local government. |
| D．It can hold more students than traditional schools. |
| A．She is truly creative and warmhearted. |
| B．She had no access to school as a child |
| C．She is devoted to designing 3D-printed products， |
| D．She raised money for kids from rural areas in China. |
| A．The advantages of 3D-printed schools. |
| B．The wide popular tyof3D-prining technology. |
| C．The significance of narrowing the global opportunity gap. |
| D．The impact of 3D-printed buildings on the environment. |
【推荐2】Making electricity out of fossil fuels releases lots of greenhouse gases, which accumulate in the atmosphere and heat up the planet. Nuclear power, on the other hand, has the potential to be an almost unlimited and more climate-friendly energy source. That is because in contrast to fossil fuels, no greenhouse gases are released directly during the immediate use of the fuel.
However, there are also several major problems. First, the mining of nuclear fuel is costly and energy intensive and causes many environmental problems. Second, nuclear energy production generates significant amounts of radioactive waste, which is extremely dangerous if not handled safely. Finally, the entire process requires very complex and energy intensive infrastructure (基建), which contributes to indirect greenhouse gas emissions.
We use computer and mathematical models to understand if it might be possible to redesign nuclear power stations in a way that they run on nuclear waste. This would reduce the negative impacts of current and future nuclear power generation immensely.
Our model show that it is feasible (可行的) to redesign nuclear power stations in a way they can run on spent nuclear fuel (SNF). Plus, the SNF does not have to be further modified before it is used. Even better, our advanced nuclear power stations do not produce any additional waste. While these innovative power stations do not yet exist, our research indicates that they are a real possibility for the future.
In our research, so-called molten salt reactors seem a promising candidate for the new type of nuclear power station as they could be redesigned to run on SNF. Molten salt reactors operate on fuel melt in liquid salt. Over a lifetime of 60 years, one of these reactors would “eat up” roughly 70 tons of SNF. This amount accumulates in 3 to 4 years of operation in a traditional nuclear power station of comparable size. Our suggested redesign would make nuclear energy generation much more efficient and sustainable, as it could “squeeze out” up to 20 times more energy from already spent nuclear fuel. It would also eliminate any SNF as a source of highly problematic waste.
Creating nuclear power stations that can run on existing nuclear waste is a worthy endeavor, and our feasibility analysis shows that it can likely be done. However, we need a lot of innovative and multidisciplinary research to put this vision into reality. “Eating up” radioactive waste as fuel would eliminate the long-term storage problem of current nuclear waste. Also, it would relieve us from the costs and environmental damages done by mining current nuclear fuel and the complicated processes required for long term operation. The new operational model would only consist of melting the SNF, operating the reactor, and cleaning the fuel salt. All in all, it would reduce many environmental, social and political issues of current nuclear power production. Using our current nuclear waste as fuel would allow us to take full advantage of the climate-friendly aspect of nuclear power generation.
Even in science and technology, it’s important to realize when we have to rethink our current approaches and what our options are for improvement. Current nuclear power stations have been created with past technologies and goals in mind. Nowadays, some people claim, they might create often more problems than they solve. We need innovative alternatives to provide sustainable, safe and clean energy for generations to come.
1. When talking about the major problems of nuclear power production, the author tries to say ________.| A．nuclear energy is not environmental-friendly |
| B．nuclear power plants deserve to be remodeled |
| C．nuclear energy is dangerous and difficult to handle |
| D．nuclear power plants are complex and hard to build |
| A．attempt | B．business | C．candidate | D．design |
| A．The proposed reactor is feasible and likely to be put into use. |
| B．The proposed reactor is economical and operationally effective. |
| C．The proposed reactor can solve the major problems previously mentioned in the passage. |
| D．The proposed reactor can use up SNF from many traditional reactors of comparable size. |
| A．Nuclear waste = fuel of the future? |
| B．Nuclear problems = efforts to solve them |
| C．Nuclear power = clean energy for the future! |
| D．Nuclear plants = innovation and multidisciplinary research |
【推荐3】Maria had a story to tell. She could hear the words and predict how the tale would unfold. All she needed, she says, was the right iPhone app.
So Maria hired a programmer, paying him $500 to deliver in five days an application that would spread her piece, called Shadows Never Sleep, through an iPhone application. The application allows Maria to tell a visual story, with white text on a black background that makes the actual appearance of the words as you zoom in (拉近) on it to follow the story through.
Maria is not alone in her attempt to adapt literature to today’s technology. Writers and publishers of all kinds are turning to technology to bring literature to the masses.
Much of the work so far has focused on converting (转换) existing printed books to an online format. Project Gutenberg is one of the most outstanding examples of that. Founded in 1971 by Michael Hart, it has turned tens of thousands of printed books into e-books, making it the first and largest single collection of free electronic books. Similarly, e-book readers such as Amazon.com Inc.’s highly publicized Kindle are designed to copy the traditional experience of reading a book, using technology to bring convenience to readers.
But the work on this front involves more than just converting traditional printed texts into electronic versions. Writers and publishers are also using technology to deliver literature in new ways using, for example, RSS feeds and text messaging. And they’re employing programming and mobile devices to develop new literary art forms, too, forcing us to reconsider how we define the term “literature”.
“I think we’re going to have to change our definition of what writing is, because electronic media is expanding the definition of what reading and writing can be,” Maria says. “It opened the door for different kinds of writing.”
1. What does the author want to show with the example of Maria?| A．Visual stories will become popular in the future. |
| B．Some people have special talent for making up stories. |
| C．Applications play an important role in today's literature. |
| D．Literature today is closely connected with technology. |
| A．word | B．story | C．text | D．application |
| A．an e-book reader | B．a kind of digital library |
| C．a website that sells e-books | D．a book publisher |
| A．Traditional printed texts are out of date. |
| B．The definition of literature has been changed. |
| C．RSS feeds and text messaging are widely used in literature. |
| D．Technology is changing literary forms and ways of publishing. |
【推荐1】In a 2012 study, Boaz Keysar, a professor at the University of Chicago in the US, led an experiment on the relationship between foreign languages and people’s way of thinking.
In the experiment, people were asked to make a choice: Just take one pound or take a 50percent chance of winning 2.50 pounds. When given this choice in their native language, most people took the safe option of only getting one pound. But they were more willing to make the riskier choice when asked in a foreign language, leading to more profits overall, according to The Guardian. As Keysar put it, “People just hate the chance of losing, but they hate it less in a foreign language.”
In another study published this year, Keysar and his team did an experiment in which participants were given a series of related words like “dream”, “snooze”, “bed” and “rest”. Later, when asked which words they remembered hearing, people were more likely to mistakenly remember “sleep”, which was not on the list, in their native language. But it was much less likely to happen if they did the test in a foreign language. As Keysar explained, people have more careful thinking when using a foreign language, leading to more accurate memories.
The foreign language effect may even influence our personality. Silvia Purpuri at the University of Trento, Italy, looked at people’s willingness to face uncertainty and enter unfamiliar situations. Being tolerant (宽容的) of uncertainty allows people to have more creative ideas and be more open to new things. It turns out that people naturally score more highly on this trait (特点) when they can speak or use a foreign language because speaking a foreign language requires taking risks.
The evidence is clear: By learning a foreign language, you’re not just learning a language—you’re gaining a new state of mind.
1. What does the first experiment suggest?| A．People like expressing in a foreign language. |
| B．People are afraid of losing in face of money. |
| C．People make quick choices in their native language. |
| D．People prefer riskier decisions in a foreign language. |
| A．Colorful. | B．Simple. | C．Usual. | D．Exact. |
| A．Cool-headed. | B．Open-minded. | C．Light-hearted. | D．Easy-going. |
| A．Learning foreign languages helps a lot. |
| B．People should learn to face uncertainty. |
| C．Foreign languages influence how people think. |
| D．Personality has an effect on language learning. |
【推荐2】A few good grades could develop a positive attitude — which could result in better grades down the line, a new study shows. The findings suggest that developing a positive, cando attitude about math can help students master the subject.
Reinhard Pekrun, a psychologist at the University of Munich in Germany, and his colleagues followed 3,425 German students from fifth through ninth grades. At the end of each year, the researchers asked the students whether they enjoyed it — or if it angered or worried them. Students also were asked whether they took pride in their math achievements or felt ashamed. The scientists then compared the students’ reported feelings about math to their grades.
It turns out that those feelings were linked with their math grades. The reverse (相反的情况) also was true. How kids felt about the subject in one year was linked to their math grades the next. Those who had gotten poor grades felt bad about math. And those who had dark emotions performed poorly. These associations between feelings and math grades showed up in both boys and girls. But girls were more likely to suffer from bad feelings about the subject. “The likely reason is gender stereotypes (有关性别的旧框框),” Pekrun says. “There’s a stereotype that girls can’t do math.” That’s not true. Large international studies show girls do just as well as boys in math.
“It does a lot to tell us how emotions might predict grades over time, (and how) doing well, in turn, predicts the emotions you’re experiencing,” says Lisa LinnenbrinkGarcia, a psychologist at Michigan State University in East Lansing. This is the first time that a study has shown that the feedback (反馈) between grades and emotions can go on for years.
Teaching math isn’t just about numbers and formulas (公式), Pekrun says. How students feel about those numbers — whether they approach them with curiosity or fear, also matters. Teachers can help by teaching concepts clearly, of course. But they also can help by grading students based on how much they improve over time. And it helps if teachers themselves have positive feelings about math, Pekrun says.
1. What does the text begin with?| A．The results of the study. |
| B．The purposes of the study. |
| C．The processes of the study. |
| D．The background of the study. |
| A．It lasted as long as about six years. |
| B．It surveyed the students on math each year. |
| C．It focused on the positive feelings about math. |
| D．It ignored the effects of grades on students’ feelings. |
| A．Their bad academic performance. |
| B．Their poor mathstudying abilities. |
| C．No positive attitude toward studies. |
| D．Misunderstandings about their math abilities. |
| A．Doubtful. | B．Confused. |
| C．Positive. | D．Dissatisfied. |
【推荐3】When Stephen Mills spotted a dusty old safe (保险箱) in a museum in Canada, he thought he’d try to crack the code (破解密码), “just like in the movies”. But when he began turning the dial, he wasn’t expecting a Hollywood ending.
For years, anyone who visited the Vermillion Heritage Museum in Alberta would have passed by a large, black metal box. Staff knew it had come from the long-gone Brunswick hotel and was donated to the museum in the 1990s, but its code and contents remained a mystery for decades — until Mills unexpectedly cracked the code.
Mills, who lived in Fort McMurray, Alberta, was visiting the museum with his family last month over a holiday weekend. As they wandered around the exhibits with the museum guide, Tom Kibblewhite, they spotted the safe.
Kibblewhite told the family what he told all other guests: the 900kg black box with a silver dial had remained closed for generations. For years, the safe has confused volunteers at the museum. The manufacturer was unable to provide advice on how to open its thick door.
A locksmith (锁匠) once suggested that years of inactivity might have slowed down the gears, making it inoperable. But Mills, who is a “mechanically-minded person”, asked whether he could give it a try. “Kibblewhite kept saying no one had opened it and that it was a mystery what was inside,” Mills said. “I thought this would be a great thing to do for a laugh for the kids. Maybe they can find some interesting historical things in it — like a time capsule.”
After pressing his ear against the cool metal, he began spinning the dial. With numbers ranging from zero to 60, he turned clockwise (顺时针方向地) three times to 20, counter-clockwise two times to 40, and then clockwise one time to 60. He was astonished to hear a click. “I jumped up and told everyone I’m buying a lottery ticket (彩票),” he said.
1. What does the underlined sentence in the first paragraph mean?| A．He didn’t think he would open the safe. |
| B．The museum trip was like a Hollywood film. |
| C．He didn’t want to turn the dial in the beginning. |
| D．It was unbelievable for him to win a lottery ticket in the end. |
| A．The dial on the safe was broken. |
| B．It was a donation from a rich businessman. |
| C．It was one of the most valuable exhibits in the museum. |
| D．It has been long closed since it was brought to the museum. |
| A．To tell people how fast time flies. |
| B．To remind visitors of the time limit. |
| C．To indicate the safe’s special meaning. |
| D．To explain the content of the safe. |
| A．Mills won a prize for cracking the code. |
| B．Mills had plenty of luck to break the code. |
| C．Mills knew what the code was in advance. |
| D．Mills tried a dozen times until he cracked the code. |
