When antibiotics（抗生素）first became available, farmers used them freely. Now scientists know that the overuse of antibiotics can cultivate drug-resistant bacteria that are dangerous to human health. Among debates over what kinds of restrictions should be put in place, figuring out how antibiotic-resistant bacteria evolve and make their way to humans remains an area of intense interest.
Jo Handelsman is tracing one such pathway that, as she puts it, travels from "farm to table."Handelsman, a microbiologist who is now associate director for science at the White House Office of Science and Technology Policy, looked into dairy cows, which are often treated with antibiotics and produce manure（排泄物）that farmers use on their crops. In addition to nutrients, that fertilizer may harbor antibiotic-resistant bacteria—a problem because the bacteria can come into contact with plants that are finally shipped to supermarkets and sometimes eaten raw.
To find out how those antibiotic-resistant bacteria come to exist, Handelsman and her colleagues at Yale University added manure from a nearby Connecticut farm to raised beds of soil in 2013. In this case, the manure specifically came from cows that were not treated with antibiotics. The researchers unexpectedly found that there were more soil bacteria carrying antibiotic-resistant genes when they were grown with the manure than when they were grown with synthetic nitrogen-based fertilizer—even though the cows were drug-free.
Previous research has found that manure from pigs treated with antibiotics contains resistant bacteria, but the cow-pie results suggest there are more factors promoting resistance besides antibiotic use. Something about manure itself may encourage naturally resistant bacteria to increase.
The findings should not, however, give the impression that resistance is everywhere, notes Lance Price, a microbiologist at George Washington University（who was not involved in the study）. "We can control this. There's very clear evidence that when we turn off the antibiotic tap, we bring down drug-resistant bacteria," says Lance.
Next on the farm-to-table schedule, Handelsman will test whether radishes grown in soil treated with cow manure are capable of taking up resistant genes from bacteria through their vascular system（循环系统）. "They have veins（血管）just like us," she says. "We don't have any evidence yet that they're taking up the bacteria, but it's a really interesting possibility."
1. What does Jo Handelsman's research focus on?| A．How antibiotics makes its way onto our table. |
| B．What restrictions should be put to antibiotics use. |
| C．How antibiotics-resistant bacteria reach human beings. |
| D．What damage the overuse of antibiotics does to humans. |
| A．Drug-free cows produced manure with antibiotic-resistant bacteria. |
| B．Synthetic nitrogen-based fertilizer did more good to the environment. |
| C．Soil bacteria carrying antibiotic-resistant genes were increasing with time. |
| D．Manure from pigs treated with antibiotics contained fewer resistant bacteria. |
| A．provide more evidence that drug-resistance bacteria are dangerous |
| B．suggest another possible explanation to the antibiotics problems |
| C．emphasize the importance of feeding cows with no antibiotics |
| D．show that the research findings may not be that worrisome |
| A．It is very likely that widespread resistance to antibiotics is not inevitable. |
| B．Plants grown in soil fertilized with cow manure may contain drug-resistant genes. |
| C．There is possibility that radishes take up resistant genes wherever they are planted. |
| D．The vascular system plays a key role in guarding radishes against bacteria. |
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【推荐1】A new analysis by researchers at MIT has found that inactive yeast (非活性酵母) can help remove lead pollution from drinking water supplies. The study shows that this approach works well, even for part-per-billion levels of pollution. The team has calculated that waste yeast abandoned by a single brewery (啤酒厂) in Boston would be enough to treat the city’s entire water supply. The system would not only purify the water but also change what would otherwise be some waste needing to be got rid of.
Lead and other heavy metals in water are a serious global problem that continues to grow. In the U.S. alone, more than 12,000 miles of waterways are suffering the effect of wastewater rich in heavy metals. What’s worse, heavy metals don’t break down, but continuously exist and accumulate. They are either impossible or very expensive to completely remove by conventional methods. Lead is highly poisonous, even at tiny concentrations, especially affecting children as they grow.“We don’t just need to minimize the existence of lead; we need to remove it from drinking water,” says one of the researchers called Stathatou.
The solution found by the MIT team is not a new one. A process called biosorption, in which inactive biological material is used to remove heavy metals from water, has been known for a few decades. But the process has been studied and characterized only at much higher concentrations, at the levels of more than one part per million.“Our study demonstrates that the process can indeed work efficiently at the much lower concentrations of typical real-world water supplies,” another researcher named Athanasiou says.
Designing a practical system for processing the water and getting back the yeast, which could then be separated from the lead for reuse, is the next stage of the team’s research. They are also exploring ways of recovering both the yeast and the lead, “We need to conduct further experiments, but there is the option to get both back. And it will be a blessing for the world.” Stathatou says.
1. What’s the feature of the new approach for removing lead pollution from drinking water?| A．It is costly but worthwhile. | B．It is economical and efficient. |
| C．It has higher technical requirements. | D．It has been questioned by many experts. |
| A．To state the necessity of removing heavy metals. |
| B．To arouse people’s awareness of self-protection. |
| C．To stress on the difficulty of removing heavy metals. . |
| D．To introduce the feature of heavy metals. |
| A．It can determine the stability of water supply systems. |
| B．It tests the inactive substances in water supplies. |
| C．It can measure the make-up of heavy metals in water supplies. |
| D．It focuses on removing heavy metals at higher concentrations from water. |
| A．Amusing. | B．Worrying. |
| C．Beneficial. | D．Adventurous. |
Supported by his research, he suggested that when predicting future successes, a person’s brainpower, as measured by IQ tests, might actually matter less than a person’s character, or EQ. Professor Salovery may be correct. For example, have you ever wondered why some of the best and smartest students in your class end up failing exams? Perhaps it is because of their EQ. People often make the mistake of thinking that EQ is the opposite of IQ. It is not. Although it is hoped that people have both high EQs and IQs, there is little doubt that those with low EQs have a hard time surviving in life.
For a long time, researchers discussed if a person’s IQ could be raised. The geneticists said no, while the social scientists said yes. Furthermore, the social scientists said that it was possible to improve a person’s EQ, particularly in terms of “people skills”, such as understanding and communication.
Recently, a professor released the findings of a study on senior high school students. When some normal students were introduced to some disabled students, they found that afterwards they were more willing to help people in difficulties. At the same time, there was a marked change in the disabled students’ attitudes. They became more positive about their disabilities and were more eager to try new things. People with high EQs often have positive attitudes towards life and are open to different ideas, so they tend to be more creative in their thinking. Please remember that having a high IQ is helpful but having a high EQ might even be more helpful.
1. According to Professor Salovery, what factor matters the most in predicting whether a person will be successful or not?
| A．How a person tests his / her brainpower. |
| B．A person’s IQ. |
| C．How smart a person is. |
| D．A person’s character. |
| A．people who have a low EQ tend to have a hard life |
| B．EQ is the opposite of IQ |
| C．people who have a high IQ always have a high EQ |
| D．people who have a high EQ always have a high IQ |
| A．Students with disabilities were not open in trying new things. |
| B．There was no change in the normal students. |
| C．The disabled students became more positive and more eager to try new things. |
| D．The disabled students were more willing to help others. |
| A．IQ is more helpful to people than EQ. |
| B．IQ can be raised by understanding and communication. |
| C．A high EQ is of great benefit in getting people promoted. |
| D．EQ can get people hired. |
| A．IQ, EQ and success. |
| B．A person’s brainpower. |
| C．IQ and a person’s character. |
| D．A person’s IQ and EQ. |
【推荐3】A food additive (添加剂) is any substance that is added to food. Many people are put off by the idea of “chemicals in food.” The truth is that all food is made up of chemicals. Natural substances like milk, as well as man-made ones like drinks on sale in the market, can be described by chemical formulas. Some chemical substances are indeed harmful, but a person who refused to consume any chemicals would find nothing to eat.
The things we eat can be divided into natural and man-made substances. Some people feel that only natural foods are healthy and that all man-made ingredients are to be avoided. But many natural chemicals, found in plants and animals, are harmful when eaten, and some laboratory-made substances increase the nutritional value of food. Other chemicals have natural and man-made forms that are exactly alike: vitamin C is vitamin C, whether it comes from a test tube or from an orange. Like “chemical”, “man-made” doesn’t necessarily mean “not fit to eat”.
Food additives are used for many reasons. We add sugar and salt and other things to foods we prepare at home to make them taste better. Food producers have developed a range of additives that stabilize, thicken, harden, keep wet, keep firm, or improve the appearance of their products. Additives can make food more convenient or nutritious, give it a longer shelf life, and make it more attractive to the consumer, thus increasing the sales and profits of the producers.
Food additives are presently the centre of a storm of serious argument. Food producers have been known to use additives that have not been proved safe; some substances in common use have been proved unsafe and have been taken off the market. Many people feel there’s a risk of eating food to which anything has been added. But food additives are now regulated by the FDA of the federal government, and new additives will go through strict testing before they can be placed on the market. For most people, the chances of developing serious side effects (副作用) from the long-term use of presently approved (批准) food additives are very small.
1. From the passage we can learn that .| A．natural foods are much safer than man-made ones |
| B．it is right to refuse chemicals in food |
| C．food additives are harmful to our health |
| D．all foods have chemical substances |
| A．Food additives can improve the quality of foods in many ways. |
| B．To ensure food safety, the FDA will stop food additives. |
| C．Foods free of additives can keep a much longer shelf life. |
| D．Foods with more additives have higher nutritional value. |
| A．new additives will be approved more easily than before |
| B．food with common-used additives will be taken off the market |
| C．food additives will be used in a safer and more scientific way |
| D．food producers won’t be allowed to use new food additives |
| A．worrying | B．acceptable |
| C．poisonous | D．avoidable |
【推荐1】So you’re going to the royal wedding! Let’s review a checklist of everything you’ll need to know.
What to wear at the ceremony
Did you get your fascinator yet? That’s a trick question because you probably don’t even know what a fascinator is. Royal dress code etiquette (礼仪) states that women must wear hats for formal events, and fascinators are the preferred accessory (配饰). These funny hats boast a large decorative design. If you haven’t packed one, no worries. Simply glue a cabbage to the side of your head. No one will be the wiser, and you can always snack on your fascinator should the wedding ceremony drag on. Gentlemen are expected to wear morning coats and top hats. Royals will likely wear their military uniforms.
Meeting the royals
Men, when greeting the royals, a simple bow will do. Not so low that it looks as if you’re examining the carpet for any medals they might have dropped. This is a slight neck bow. Women perform a curtsy. Simply put one leg behind the other, bend your knees, bow your head slightly and fall over because you’ve never done this before.
Chatting up the queen
The first rule of talking to the queen: Don’t talk. That is, unless spoken to. If she does start a conversation and you find you’ve run out of interesting stuff to discuss after “Hello”, break the ice with a joke. “Hey, why did the queen go to the dentist?” “To get her teeth crowned!”
Dining
Every meal begins and ends with the queen. You can’t start eating until she starts, and you stop when she stops. The queen doesn’t appear to be a large eater, so you should wolf down your food in case she pushes the plate away after a few bites. When dining, the royals hold knives in their right hand and forks in their left with the tines facing down.
1. What must women have on for the royal wedding?| A．Morning coats |
| B．Military uniforms |
| C．Hats with fascinators |
| D．Cabbages |
| A．Fall over when you bow to the queen |
| B．Don’t start eating until the queen starts |
| C．Don’t talk even if spoken to |
| D．Push the plate away while eating |
| A．Humorous |
| B．Serious |
| C．Plain |
| D．Official |
【推荐2】Montreal may have more media connections and commercial(商业的)activities, but Quebec City has something else: the French Canadian identity and soul(灵魂).You can get a taste of the city in a single day but stay at least a weekend if you can.The little city shines brightest when you slow down.
The beautiful old town, which is a UNESCO World Heritage site, sits above the St Lawrence River.It is a living museum of narrow stone streets, 17th-and-18th-century houses and churches.The Notre - Dame- de- Quebec was the first church in North America.It got its start as a small Catholic church in 1647 but has been rebuilt repeatedly to repair damages from wars, including the British-French war of 1759.
No matter whether it's summer or winter, people in Quebec City love to get outdoors-and the perfect place to join them is at Battlefields Park.Covering 2.3 km2.Battlefields Park was once the largest fort(堡垒)in North America.It was built by the French in the 1750s and completed by the British in 1850 to defend against an American invasion that never came.In summer, actors in costume bring this history to life on Abraham’s Bus Tour.Year-round creative multimedia programs achieve a similar effect at the park gate.
Quebec City also tries its best to entertain its visitors.All summer and fall long,musicians and actors in costumes take to the streets, while fantastic festivals fill the air with fireworks and songs.In the coldest months of January and February, Quebec's Winter Carnival has the biggest and most colorful winter parties around Canada. Spring brings beautiful flowers, much lower prices and thinner crowds.
1. How is Quebec City different from Montreal?| A．Quebec City is bigger than Montreal. |
| B．Quebec City has more media companies. |
| C．Quebec City has busier commercial activities. |
| D．Quebec City is better known for French culture. |
| A．It is a church with a long history. | B．It has suffered damages from wars. |
| C．It has to be expanded many times. | D．It is a UNESCO World Heritage site. |
| A．Carnival parties. | B．Costume plays. |
| C．Low-price flowers. | D．Fireworks and songs. |
| A．Spring. | B．Summer. |
| C．Fall. | D．Winter. |
【推荐3】Weather forecasters in the Philippines got the warning in the second week of November 2020. A forecast that went further into the future than usual warned that the islands faced fierce rains more than three weeks away. The meteorologists(气象学家) reminded local and national governments to spring into action. The governments responded by sending mobile phone messages and broadcast alarms to advise people to prepare to move away from dangerous places to other ones.
By the time the Category 4 Typhoon Kammuri struck the Philippines with heavy rains in early December, the damage was much less than it could have been. “Having so much time to prepare was key,” says Andrew Robertson, a climate scientist at Columbia University. “It’s a great example of how far we’ve come in weather forecasting. But it’s just not enough. We still need to go further,” he says.
Such efforts, known as “subseasonal(次季节的) forecasting”, aim to fill a critical gap in weather prediction. The approach fits between short-term forecasts that are good out to about 10 days in the future and seasonal forecasts that look months ahead.
A subseasonal forecast predicts average weather conditions three to four weeks away. Each day of additional warning gives emergency managers much more time to prepare for incoming heat waves, cold currents, tornadoes or other wild weather. Groups such as the Red Cross are starting to use subseasonal forecasts to strategize for weather disasters, such as figuring out where to move emergency supplies when it looks like a tropical cyclone(气旋) might hit a region. Farmers look to subseasonal forecasts to better plan when to plant and irrigate crops. And operators of dams and the power station could use the information to get ready for extra water that may be soon taxed on the systems.
Subseasonal forecasting is improving slowly but steadily, thanks to better computer models and new insights about the atmospheric and oceanic patterns that drive weather over the long term.
1. What did the Philippine government try to do before fierce rains?| A．Persuade citizens to stay at home. | B．Warn citizens against walking around. |
| C．Advise citizens to move to some safer places. | D．Warn citizens to focus on the weather forecast. |
| A．It is always timely. | B．It still needs improving. |
| C．It has caused damage to crops. | D．It shows the perfection of the technology. |
| A．Its origin. | B．Its cost. | C．Its warning. | D．Its application. |
| A．Subseasonal Forecasting Has Its Disadvantages |
| B．Subseasonal Forecasting Could Improve Lifestyle |
| C．Subseasonal Forecasting Could Save Lives from Disasters |
| D．Subseasonal Forecasting Has an Effect on Farming |
