1 . Amblyopia is the most common cause of vision loss in children. In all cases of amblyopia, there’s a stronger eye and a weaker eye, and it’s winner-take-all in the cortex (大脑皮层). The cortex learns to ignore the signal from the weaker eye. By ignoring the weaker eye, the brain doesn’t fuse (融合) images from both eyes. As a result, people with amblyopia can have trouble seeing in 3D.
In an attempt to solve this problem, doctors start treating patients with amblyopia at a young age, while their brain pathways are still developing. The children, usually under 7 years old, are often told to wear an eye patch over their strong eye to force the brain to rely on the weaker. But whenever the eye patch is removed, the competition can start over. For lasting improvement, new treatments need to teach the brain to stop suppressing (抑制) key visual cues coming from the weaker eye, says neuroscientist Dennis Levi of the University of California.
Now, several research teams are taking a new way that aims to get the brain to make better use of the information coming from both eyes, Several companies are working on treatments based on this new angle. One is called Luminopia.
Luminopia’s therapy involves having children watch videos through a virtual reality headset. As the children watch, the headset blocks out certain parts of the display for each eye, so the patients actually have to combine input from the two images to get the full video.
The company conducted a trial showing that children with amblyopia begin to see better on eye chart assessments after three months of one-hour sessions done six days a week, But they have yet to measure improvements in long-term effectiveness. It is believed that if people with amblyopia don’t learn to fuse signals from both eyes from a young age, they never will. So some scientists think attempting to treat adults, whose brains have suppressed signals from their weak eye for decades, is a lost cause.
1. Why does a person with amblyopia have trouble seeing in 3D?| A．His brain is unable to receive images. |
| B．His cortex overlooks signals from the weaker eye. |
| C．His stronger eye can’t send signals to the brain. |
| D．His weaker eye fails to receive signals. |
| A．Ineffective. | B．Temporary. |
| C．Wonderful. | D．Comprehensive. |
| A．Activating the weak eye to get the full video. |
| B．Forcing the brain to rely on the weaker eye. |
| C．Improving the situations with eye chart assessments. |
| D．Blocking out the images received from the stronger eye. |
| A．It has an instant effect. | B．Adults are is main targets. |
| C．More trials need to be conducted. | D．It has long-term effectiveness. |
1. What’s the woman doing?
| A．Seeing a doctor. | B．Doing a test. | C．Asking for advice. |
| A．She has to take some pills. | B．She needs more tests. | C．She has nothing serious. |
| A．Excited. | B．Concerned. | C．Uninterested. |
| A．Choose an easy sport. | B．Keep exercising. | C．Take a slow lifestyle. |
| A．She is busy. | B．She is ill. | C．She doesn’t have money. |
4 . People who have a diet rich in flavanols (黄烷醇), which are found in tea, apples and berries, may be less likely to develop age-related memory loss, research suggests. A three-year study of 3,562 people aged about 71 found those with high regular flavanol consumption had better hippocampal (海马的) memory function, which includes short-term memory-making, than those who didn’t.
Lead scientist Scott Small said the findings formed part of a growing body of research that is “starting to reveal that different nutrients are needed to strengthen our ageing minds”.
The scientists randomly assigned healthy adults to receive either a daily 500mg flavanol supplement or an artificial pill for three years. The participants took several memory tests during the study period and filled in surveys that assessed their diet. The researchers said memory scores improved only slightly for the group taking the flavanol pill, but that within that group some people who had poor diet and low flavanol consumption at the beginning of the study, saw their memory scores increase by 16% compared with the start of the study.
Prof Aedin Cassidy, an expert from Queen’s University Belfast, said it was a “really important study”, especially since the amount required for brain health improvement was “readily achievable”. “For example, one cup of tea, six squares of dark chocolate, a couple of servings of berries and apples would together provide about 500mg of flavanols,” he said.
However, David Curtis, an honorary professor at the UCL Genetics Institute, said, “The study fails to provide evidence that increasing flavanol intake is beneficial and there is no need for anybody to consider changing their diet in the light of its findings.”
Carl Hodgetts from University of London, said research into the relationship between nutrition and the brain could help with the fight against dementia (痴呆). He said it was “an interesting study that starts to address such questions” but disagreed with the conclusion that flavanol supplements affect hippocampal function, as MRI scans would be needed to establish this.
1. What can we learn about the flavanol?| A．It can lead to our ageing mind. |
| B．It can be acquired easily in our daily life. |
| C．It hardly affects long-term memory-making. |
| D．It can limit hippocampal memory function. |
| A．People taking artificial pills. |
| B．People controlling their diet. |
| C．People taking more flavanols than others. |
| D．People lacking flavanols before the study. |
| A．Divided. | B．Carefree. | C．Doubtful. | D．Opposed. |
| A．Balanced Diet: Necessary for Old People |
| B．Different Nutrients Affect People’s Memories |
| C．Flavanols: A Way to Reduce Memory Loss of the Elder |
| D．Flavanol Supplements Can Help Prevent Certain Diseases |
5 . In the second half of the 18th century, a British doctor named Edward Jenner gave his gardener’s son cowpox (牛痘) and then deliberately infected him with smallpox (天花) to test his assumption that people who were frequently exposed to cowpox, a similar but less severe virus, would avoid catching smallpox. It worked and cowpox as the vaccine (疫苗) was highly effective. “Vaccination”, from the Latin word for cow, soon became commonplace.
Challenge trials are forms of research where, rather than relying on data from natural infections, we intentionally expose someone to a disease in order to test the effectiveness of a vaccine or treatment. Things have changed a lot since Jenner’s time, of course, when it was not uncommon for doctors to conduct this kind of research. Even so, there’s a continuous sense that there’s something immoral about making someone ill on purpose.
But this shouldn’t blind us to the extraordinary power of challenge trials. They could become increasingly important weapons in the medical research, in a situation where vaccine technology is advancing and the threat of diseases jumping from animals into human beings is increasing.
Much has been done to reduce the risks of challenge trials. Like respiratory syncytial virus (RSV), researchers have involved adults who are at a low risk of severe illness. These acts have already cut down a massive range of vaccine candidates. But not all diseases are like these ones. We don’t always know the dangers volunteers might face; we don’t always have treatments ready. What then?
We could, of course, just avoid these questions entirely, and rely on other types of research. But that doesn’t always work: sometimes, animal testing is tricky and uninformative, because the disease doesn’t develop in the same way as it would in humans. In contrast, challenge trials can be deeply informative within weeks, with far fewer volunteers. And the benefits can be surprisingly high.
In order to make sure we are as protected as possible from current and future threats, we should try to get rid of the misbelief in challenge trials, making them a more familiar part of our tool kits. Perhaps the greatest reward of all would be to make sure participants’ efforts are worthwhile: by designing trials to be fair and effective and applying them when and where they might make a real difference. In short, by helping them to save thousands, if not millions of lives.
1. The author tells the story of Edward Jenner with the intention of ________.| A．defining what are challenge trials. |
| B．showing the origin of the word “vaccination”. |
| C．emphasizing the importance of his vaccine. |
| D．introducing the topic of challenge trials. |
| A．The issues behind challenge trials are easy to solve. |
| B．Despite the risks, challenge trials can benefit numerous lives. |
| C．The dangers of challenge trials outweigh the benefits they bring. |
| D．Challenge trials can prevent the development of vaccine technologies. |
| A．A cautious attitude should be taken towards challenge trials. |
| B．Challenge trials guarantee participants protection against threats. |
| C．People should be more open to challenge trials. |
| D．The accuracy of challenge trials can be improved with more volunteers involved. |
| A．Can challenge trials block medical progress? |
| B．Should we use challenge trials to find cures? |
| C．Can challenge trials put an end to infectious diseases? |
| D．Should we replace animal testing with challenge trials? |
1. Why didn’t Mike take an examination yesterday?
| A．Because he didn’t want to do so. |
| B．Because he got sick. |
| C．Because he got the examination date wrong. |
| A．Have an examination at home. |
| B．Have an exam sometime later when he got better. |
| C．Have an exam next term. |
| A．Show the woman the way to the nearest hospital. |
| B．Ask some local people to help. |
| C．Call 120 for the woman’s mom. |
1. Why was the woman absent last week?
| A．Because she was tired. |
| B．Because she had a cold. |
| C．Because she took care of her brother. |
| A．About 2 hours by train. |
| B．About 6 hours by train. |
| C．About 6 hours by plane. |
1. 活动的重要性；
2. 你的建议。
注意：
1. 词数100左右；
2. 可以适当增加细节，以使行文连贯。
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1. Where does the conversation probably take place?
| A．At home. | B．At the doctor’s. | C．In a drugstore. |
| A．Buy more medicine. | B．Put on his glasses. | C．Read the instructions. |
| A．In the car. | B．In a bag. | C．On a table. |
