At 18, Ashanthi De Silva of suburban Cleveland is a living symbol of one of the great intellectual achievements of the 20th century. Born with an extremely rare and usually fatal disorder that left her without a functioning immune system, she was treated beginning in 1990 with a revolutionary new therapy that sought to correct the defect at its very source, in the genes of her white blood cells. It worked. Although her last gene-therapy treatment was in 1992, she is completely healthy with normal immune function, according to one of the doctors who treated her, W. French Anderson of the University of Southern California. Researchers have long dreamed of treating diseases from hemophilia to cancer by replacing mutant (变异的) genes with normal ones. And the dreaming may continue for decades more. "There will be a gene-based treatment for essentially every disease, "Anderson says, "within 50 years."
It's not entirely clear why medicine has been so slow to build on Anderson's early success. The National Institutes of Health budget office estimates it will spend $432 million on gene-therapy research in 2005, and there is no shortage of promising leads. The therapeutic (有益健康的，有治疗性的) genes are usually delivered through viruses that don't cause human disease.
At the University of Pennsylvania's Abramson Cancer Center, immunologist Carl June recently treated HIV patients with a gene intended to help their cells resist the infection. At Cornell University, researchers are pursuing gene-based therapies for Parkinson's disease and a rare hereditary disorder that destroys children's brain cells. At Stanford University and the Children's Hospital of Philadelphia, researchers are trying to figure out how to help patients with hemophilia who today must inject themselves with expensive clotting drugs for life. Animal experiments have shown great promise.
But somehow, things get lost in the translation from laboratory to patient. In human trials of the hemophilia treatment, patients show a response at first, but it fades over time. And the field has still not recovered from the setback it suffered in 1999, when Jesse Gelsinger, an 18-year-old with a rare metabolic disorder, died after receiving an experimental gene therapy at the University of Pennsylvania. Some experts worry that the field will be tarnished (黯淡的) further if the next people to benefit are not patients but athletes seeking an edge. This summer, researchers at the Salk Institute said they had created a "marathon mouse" by implanting a gene that improves running ability; already, officials at the World Anti-Doping (反兴奋剂) Agency are preparing to test athletes for signs of "gene doping. "But the principle is the same, whether you're trying to help a healthy runner run faster or allow a muscular-dystrophy patient to walk. "Everybody recognizes that gene therapy is a very good idea," says Crystal. "And eventually it's going to work."
1. According to the passage, we know that ________.| A．Jesse Gelsinger give an example of modern treatment for fatal diseases |
| B．the case of Ashanthi Desilva shows the promise of gene-therapy |
| C．researchers have improved people's running ability by implanting a gene |
| D．The gene-therapy way has cured many serious diseases |
| A．greatly speeded the development of medicine |
| B．brought no immediate progress in the research of gene-therapy |
| C．realized his dream |
| D．made him a national hero |
| A．Ashanthi needs to receive gene-therapy treatment constantly. |
| B．Despite the huge funding, gene researches have shown few promises. |
| C．Therapeutic genes are carried by harmless viruses. |
| D．Gene-doping is encouraged by world agencies to help athletes get better scores. |
| A．troubled | B．pessimistic |
| C．optimistic | D．uncertain |
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【推荐1】Flu vaccines (疫苗) work by arming the immune system with an enhanced ability to recognize and fight off the flu virus.Vaccines introduce proteins found on the surface of fu viruses，causing the immune system to produce antibodies that are ready to react when the virus attack.
However, flu viruses change frequently and can differ with time and from region to region.Even though current vaccines that people get annually produce antibody responses, these antibodies don‘t cross-protect. If thereis a new flu strain (流感病毒毒株) not found in that year’s vaccine, the antibodies that we generated last year won’t be able to protect us. So the pandemic(大流行) happens.On the other hand, if the vaccine matches the virus strain, the immune system will produce antibodies and kill the flu virus.
Luckily, in a study published in Cell Reports Medicine,scientists at the University of Wisconsin-Madisondescribe a T-cell-based vaccine strategy that is effective against multiple strains of flu virus. The experimental vaccine, given through the nose, delivered long-lasting protection in the lungs of mice by using T-cels, which are special white blood cells that quickly remove viral invaders through an immune response.
The research suggests a potential strategy for developing a universal flu vaccine, "so you don’t have to make a new vaccine every year," explains Marulalsiddappa Suresh, a professor in the School of Veterinary Medicinewho led the research. The current flu vaccine has a serious weakness. Because each vaccine is only designed to resist one kind of virus strain. Once the virus changes, it could lead to a wide outbreak of flu.
By using T-cell immunity against multiple strains,it may be possible to develop a vaccine that is effective against a number of circulating flu viruses. In particular,the new approach calls into action tissue-residentmemory T-cells, or TRM cells，which live in the airways and lining of lung epithelial (表膜的) cells and fightinvading viruses. Like highly-trained soldiers，TRM cells serve as front line defense against infection. This undoubtedly gives a totally new way to fight the flu virus.
1. Why do flu pandemics break out occasionally even if vaccines are given?| A．Because vaccines lose their expected effects. |
| B．Because the flu strains reproduce very quickly. |
| C．Because the strains have resistance to vaccines. |
| D．Because vaccines don't work against new strains. |
| A．They are in charge of generating viruses. |
| B．They can protect white blood cells very well. |
| C．They kill viral invaders automatically. |
| D．They can generate white blood cells. |
| A．It will fundamentally stop the formation of new cold viruses. |
| B．It will cut off the ability of the flu virus to spread. |
| C．It points out the direction of developing a universal flu vaccine. |
| D．It enables humans to get rid of the common cold completely. |
| A．New Vaccine Strategy to Provide Protection Against Flu |
| B．New Immune System Intended for Fighting the Flu |
| C．New "Vaccine Based on T-cells Successfully Kills the Flu Virus |
| D．Serious Weakness of the Current Flu Vaccine Found |
【推荐2】With greater attention paid to our mental health, we need more chances to pour out our anxieties. But talking to an adult about feelings can be an uneasy experience for children and adolescents. With this in mind, a recent study from the University of Cambridge tested a robot’s effectiveness in determining children’s well-being.
The study involved 28 children between the ages of 8 and 13 and their parents or guardians completing a well-being questionnaire focused on the young individuals. Then a human-like robot asked the young participants open-ended questions about happy and sad memories over the last week and had them respond to prompts (提示) around pictures. The parents or guardians and research team members observed the interaction from a separate room.
Children with mental well being issues were likelier to divulge the extent of these problems while talking to the robot. Researchers thus found they felt more negative than stated in the initial questionnaire. On the other hand, children without previously stated mental well-being concerns presented an even more positive image to the robot.
Actually, the idea that children would share more with a robot than parents or mental health professionals is easy to understand. “Not all children have a secure attachment style, meaning they feel safe and connected to their caregivers,” says Dr. Katherine Grill, a behavioral scientist. “Children without secure attachments often find comfort in companions like imaginary friends. In this instance, a robot may serve as a practical option for children to open up about their well-being. Even in cases where children have secure attachment styles, a robot may provide them with a non-judgmental relationship where they’re willing to share their feelings.”
“While this study demonstrates the benefit of robots, it doesn’t remove the need for human interaction in the mental health field. Technology-enabled services mean digital support and even enhanced care, but they don’t replace work with a human being,” says Dr. Aaron Haddock, associate professor of Clark University. “After all, the relationship between clients and providers is a key driver of positive treatment outcomes.”
1. Which of the following is true about the study?| A．The robot raised questions to test children’s memory. |
| B．The children interacted with a human-like robot alone. |
| C．The children were free to ask the robot any questions. |
| D．The parents talked with researchers in a separate room. |
| A．Ignore. | B．Assess. | C．Reveal. | D．Control. |
| A．Because robots are more intelligent than humans. |
| B．Because robots offer non-judgmental relationships. |
| C．Because robots connect children with their caregivers. |
| D．Because robots can choose imaginary friends for the children. |
| A．Totally positive. | B．Relatively objective. |
| C．Particularly disapproving. | D．Generally unconcerned. |
【推荐3】When it comes to health, everyone wants the best for themselves and their families. You can help prevent the spread of COVID-19 by seeing the latest information from the WHO. What is COVID-19?
Make sure you and people around you, follow good respiratory hygiene （呼吸卫生）.This means covering your mouth and nose with your tissue when you cough or sneeze. Then handle the used tissue immediately and wash your hands. Why?
Stay home if you feel unwell. If you have a fever, cough and difficulty breathing, seek medical attention and call in advance. Follow the directions of your local health authority. Why? National and local authorities will have the most up to date information on the situation in your area. Calling in advance will allow your health care provider to quickly direct you to the right health facility.
| A．Droplets spread virus. |
| B．People can catch COVID-19 from others who have the virus. |
| C．What can I do to protect myself and prevent the spread of disease? |
| D．However, the situation is unpredictable so check regularly for the latest news. |
| E．Maintain at least 1 metre distance between yourself and anyone who is coughing. |
| F．It is a infectious disease caused by the most recently discovered coronavirus. |
| G．This will also protect you and help prevent spread of viruses and other infections. |
【推荐1】Wildfires have captured headlines around the globe in recent years. These intense and widespread fires worry scientists. Besides causing billions of dollars in property damage, wildfires can erase the habitat of valued wildlife. They also fill the air with choking pollution. And when they burn near cities, they put the lives of whole communities in danger.
But scientists are interested in these fires for another reason. The black carbon-rich smoke from their flames is made of the ash from burned trees, grass and shrubs. The intense heat of some wildfires can cast this ash to high altitudes and it can travel around the globe.And the warming sunlight absorbed by dark particles(微粒)at high altitudes won't reach Earth's surface.
Scientists refer to those tiny particles of ash,dust and more as aerosols(气溶胶). One important trait is how well they reflect light. Snow and white ice reflect the most light. Dark things absorb the sun's light, mostly as heat. So the color of aerosols is important. Those aerosols can either warm or cool the air. Overall, researches showed that smoke aerosols cool the atmosphere. As intense fires cause dark ash aerosols high into the air, they mix with clouds and mostly prevent the sun's energy entering the earth.
The warming climate that can lead to wildfires may experience a temporary cooling when serious wildfires do erupt. Meanwhile, fire aerosols also can have bad effects when they fall back to Earth. And that fallout can sometimes be up to half a world away from where a fire took place.
Many studies show that intense wildfires are becoming more common, partly because of global warming. As the planet warms and new fires occur, scientists will continue to explore the big impact of tiny fire aerosols that temporarily occupy our atmosphere.
1. What does paragraph 1 focus on?| A．Wildfire-related air pollution. | B．Cities suffering from wildfires. |
| C．Harmful effects of wildfires. | D．Scientists' concern over wildlife. |
| A．By absorbing the sun's heat. | B．By reflecting most sunlight. |
| C．By blocking out dark clouds. | D．By clearing away clouds. |
| A．Uncaring | B．Cautious. | C．Disapproving. | D．Supportive. |
| A．How wildfires affect the climate. | B．Why warming causes wildfires. |
| C．Common occurrence of wildfires. | D．Serious damage from wildfires. |
“Planting trees is one way, but it isn’t that simple. It doesn’t solve the basic issue of water resources,” says Wu Bo, a professor. “We need to calculate how much water the trees will absorb, or else it could have a negative effect.”
Villagers in Zhengxin have taken on this challenge, with limited success. When the irrigation channels began to run dry, Lu Xianglin switched from wheat to cotton on his land. He also planted trees to protect his fields from sandstorms. He says he still gets good yields（产量） using flood irrigation and earns a good income for his family.
Other farmers haven’t stuck it out（坚持到底）: about one in three have left Zhengxin in the past 10 years after their wheat crops died. Young people who can find jobs in the towns rarely return.
Last week, Mr Lu joined the other men in his village on a government-arranged trip to see the land that has been set aside for their relocation, nearly 40 miles to the south. The next day, he was back, shaking his head at the plan. The idea of uprooting his family troubles him, as does the idea of giving up the land that fed his forefathers. He prefers to stay and keep up the fight.
“With enough water, this problem can be solved,” Lu says. “We can plant trees and grass, and they will grow bigger. That will stop the desert.”
Experts say that farmers could switch to drip irrigation （滴灌）to lessen their water intake for growing crops. Elsewhere in the region, farmers have built brick greenhouses as part of a plan to grow vegetables using less water. Roadside signs urge farmers to “Save Water, Protect the Environment”.
1. The negative effect of planting trees in deserts is that __________.
| A．it can make groundwater become less |
| B．it can prevent the sand moving freely |
| C．it can stop crops growing well |
| D．it can get the soil to become poor |
| A．Because the plan of relocation will cost him much money. |
| B．Because his family had trouble moving away. |
| C．Because he was reluctant to give up his land. |
| D．Because he would rather stay than fight against the deserts. |
| A．The deserts drive more and more people to leave their homes for their lives. |
| B．People have no means to fight against the land becoming desert. |
| C．Water is the biggest barrier for people to stop the desert. |
| D．Planting trees cannot solve the problem of desertification of farmland. |
| A．To plant more trees. |
| B．To build greenhouses. |
| C．To change crops. |
| D．To use drip irrigation. |
【推荐3】According to the Nordic (北欧的) legend, “ship worms will not go deep into the wood which has been painted with the seal-tar.” Scholars still debate the meaning of “seal” in “seal-tar”. one is that they mixed tar (清漆) with animal fat. Some experiments suggest this may keep ship worms away. It is clear that tar was an important technology. New findings suggest that a vast industry making it appeared at the beginning of the Viking Age, helping enable their wild ambition.
The oldest tar pits (坑) in Sweden date from around 100 A.D. to 400 A. D. The first were discovered in the early 2000s close to an ancient village suggesting that tar was initially for painting houses and household items. It was made by putting pine wood into pits a metre or two wide, setting it on fire and covering it with fuels to encourage a slow burning. In this way, the wood’s resin (树脂) would turn to tar.
However, as Andreas Hennius, an archaeologist (考古学家) reports, around the eighth century something occurred. The pits got bigger — reaching eight to ten metres in diameter — and moved far into the forest. These pits could have made around 300 litres of tar in a single production.
Mr. Hennius argues that the builders needed all this for ships. The eighth century was when sails arrived in northern Europe. That is no coincidence. Tar has been found on all parts of ships, whether big or small. It was used to make ships safe from water. It was also mixed with other paints to give sails color and offer protection from the sun. This expanded opportunities for long-distance trade, and the large, swift attacks defining the Viking Age.
1. What is the recent discovery according to the passage?| A．The function of tar. | B．The actual meaning of “seal”. |
| C．The times for large-scale tar production. | D．The major role of tar making industry. |
| A．The tar production started as an industry first for ship building. |
| B．The pits around the forest were not suitable for mass production. |
| C．Tar became an industry thanks to adequate supply of fuels around. |
| D．The pits were discovered over 2000 years after their first construction. |
| A．tar was commonly painted on ships | B．other paints could protect ships |
| C．more pine wood was around the pits | D．there were bigger pits than before |
