1 . Here on Earth where most of us live, we spend about a third of everyday lying down sleeping and two-thirds standing or sitting in an upright position.
That's not really how it goes in space when people are weightless and the zero gravity environment causes more liquid to shift to the head. Faces get swollen, legs lose volume and appear to be smaller. Many astronauts have complained of eye and back problems after coming back down to Earth and its gravity.
And now scientists say they have discovered some new risks with long-term space flight. A study published recently in JAMA Network Open, a medical journal, examined 11 healthy astronauts who had been on the International Space Station for six months. Eight of them had unusual characteristics observed in their blood. For instance, six of the astronauts had reverse （反向的）blood flow from their heads.
The lead author of the study says he doesn't know if that's actually harmful. The blood is still leaving the head from other pathways, so flowing backwards through a jugular vein（颈静脉） may not be dangerous. But he says it does show a change in how blood moves through the body while in space.
Another issue the study found was blood clots （凝块）. One astronaut had one. Another showed signs of a partial blood clot. That is potentially harmful as the clots can block the flow of blood to the lungs. The astronaut who had one was treated for the rest of the spaceflight and made it home safely.
What does all this mean? Well, one researcher says these issues have probably been oc- curring since humans first went into space and that they would likely resolve themselves when astronauts came back down to Earth. Knowing about them now gives doctors something else to monitor when people leave our atmosphere.
1. What causes the physical problems for astronauts?| A．Sleeping for a long time. | B．The zero gravity environment. |
| C．Staying in the spaceship. | D．The shift in their bodies. |
| A．Four. | B．Three. | C．Two. | D．One. |
| A．It is a common problem. | B．It is a new kind of disease. |
| C．It is a threat to people's health. | D．It was first found by astronauts. |
| A．Doctors have a new task for astronauts |
| B．Zero gravity stops astronauts flying in space |
| C．It's dangerous for astronauts to fly into space |
| D．New risks are found in long-term space flight |
2 . More young Chinese are making preparations for their future by buying life and medical insurance, Chen Meiling reports. Jessie Dong, 30, sent her life insurance policy to her mother, which says, if she dies before 50, family members will get a compensation (补偿)of 3 million yuan (S458,820).
Recently, the only child of her mother's colleague died at the age of 35, and all that was left to his lonely, old parents was sorrow. Dong, a researcher of social science in Beijing, says she doesn't want such a tragedy (悲剧) to happen, and hopes to be able to support her family even if she is gone. Buying insurance became one of her wisest choices.
She pays about 350 yuan every month for the life insurance, and about 300 yuan annually for critical illness insurance with coverage of 4 million yuan, in case she runs out of money for “having to treat a serious disease someday” "It's a good way to face the unpredictable risks of life with a small amount of money. Of course hopefully I won't use it," she says, adding she purchased insurance on Alipay, as she is too busy to visit insurance companies in-person, and she plans to continue investing (投资)in it.
The younger generation, those born in the 1990s, in China is showing a higher interest in buying insurance, driven by the increased awareness of crisis and a willingness to improve risk resistance ability, experts say. The fact that more people get severe diseases at a younger age or feel their worse health condition, as well as uncertainties brought about by the COVID-19 pandemic(流行病) to both their personal lives and on a Socio-economic level, also strengthens anxiety and is contributing to the trend.
1. What does the first paragraph mainly tell us?| A．The young are afraid of dying. |
| B．Jessie Dong’s mother has passes away. |
| C．Jessie gain a large sum. |
| D．Buying life insurance’s popular with the young. |
| A．By WeChat. | B．By Alipay. |
| C．In cash. | D．By Taobao. |
| A．Their serious diseases and poor health. |
| B．Their higher interest and awareness of crises. |
| C．Their life of high quality and living standard. |
| D．Their personal lives and socio-economic level. |
| A．A Future Plan | B．A Good Choice |
| C．A Health Investment | D．A Large Company |
3 . Researchers at CU Boulder have developed a wearable device that changes the human body into a biological battery. The device is stretchy(弹性的) enough that you can wear it like a ring, sport band or any other thing that touches your skin. It also taps into a person's natural heat-employing thermoelectric generators to change the body's internal temperature into electricity. "In the future, we want to be able to power your wearable electronics without having to include a battery," said Jianliang Xiao, an associate professor at CU Boulder.
The concept may sound like something out of The Matrix film series, in which a race of robots have enslaved humans to harvest their precious organic energy. Xiao and his colleagues aren't that ambitious: Their devices can generate about 1 volt (伏特) of energy for every square centimeter of skin space-less volt per area than what most existing batteries provide but still enough to power electronics like watches or fitness trackers.
Scientists have previously experimented with similar wearable devices, but Xiao's is stretchy, can heal itself when damaged and is fully recyclable-making it a cleaner alternative to traditional electronics. "Whenever you use a battery, you're depleting(消耗) that battery and will, eventually, need to replace it," Xiao said. "The nice thing about our device is that you can wear it, and it provides you with constant power."
Just pretend that you're out for a jog. As you exercise, your body heats up, and that heat will radiate out to the cool air around you. Xiao's device captures that flow of energy rather than let it go to waste. "The thermoelectric generators are in close contact with the human body, and they can use the heat that would normally be sent into the environment," Xiao said.
1. What does Xiao expect of his device at present?| A．It will be used for medical purposes. |
| B．It will be made smaller and wearable. |
| C．It will change natural power into electricity. |
| D．It will supply constant power to wearable devices. |
| A．To give an explanation. | B．To make a comparison. |
| C．To introduce a topic. | D．To analyze the cause. |
| A．The strengths of Xiao's device. |
| B．The convenience of using a battery. |
| C．The replacement of wearable devices. |
| D．The development of traditional electronics. |
| A．It operates with plenty of power. |
| B．It is designed for practical use. |
| C．It benefits people's health in a way. |
| D．It's based on traditional electronics. |
4 . More than half the world’s population live in cities, and by 2050 the UN expects that proportion to reach 68%. This means more homes, roads and other infrastructure. In India alone, a city the size of Chicago will have to be developed every year to meet demand for housing. Such a construction increase is a bad sign for dealing with climate change, because making steel and concrete, two of the most common building materials, generates around 8% of the world’s CO2 emissions (排放). If cities are to expand and become greener at the same time, they will have to be made from something else.
Wood is one of the most promising sustainable (可持续的) alternatives to steel and concrete. It is not, however, everyday wood that is attracting the interest of architects.
Rather, it is a material called engineered timber. This is a combination of different layers, each designed to meet the requirements of specific parts such as floors, panels and beams (横梁). Designers can use it to provide levels of strength like steel, in a product that is up to 80% lighter. In addition, engineered timber is usually made into large sections in a factory for future use, which reduces the number of deliveries to a construction site.
According to Michael Ramage of the University of Cambridge, a wooden building produces 75% less CO2 than a steel and concrete one of the same size. However, if building with wood takes off, it does raise concern about there being enough trees to go round. But with sustainably managed forests that should not be a problem, says Dr Ramage. A family-sized apartment requires about 30 cubic metres of timber, and he estimates Europe’s sustainable forests alone grow that amount every seven seconds. Nor is fire a risk, for engineered timber does not burn easily. Besides, fireproofing layers can be added to the timber. All in all, then, it looks as if wood as a building material may get a new lease of life.
1. Why is India mentioned in paragraph 1?| A．To point out the severe pollution. |
| B．To predict the population increase. |
| C．To indicate the high degree of urbanization. |
| D．To show the great need for building materials. |
| A．It is produced at a low cost. |
| B．It hardly appeals to architects. |
| C．It helps save energy in transportation. |
| D．It possesses greater strength than steel. |
| A．Becomes cheaper. | B．Gains popularity. |
| C．Requires less work. | D．Proves sustainable. |
| A．Making Future Cities More Attractive |
| B．Living in a World with Less Emission |
| C．Building Sustainable Cities with Woods |
| D．Growing More Trees for Future Building |
5 . The planets Jupiter (木星) and Saturn (土星) have been moving closer and closer to each other in the night sky. In fact, on December 21 , they appeared closer together than they have been in hundreds of years.
When two astronomical bodies appear close in the sky, as seen from Earth, it is called 4 conjunction (合相). Conjunctions can happen with any two bodies, such as planets, moons, stars and asteroids (小行星). When Jupiter and Saturn come together, it is called a "Great Conjunction".
Astronomers say these events between the two largest planets in our solar system are not rare. Jupiter passes its neighbor Saturn once every 20 years as they circle around the sun. But this conjunction is especially close: From Earth, the two planets will look to be just one-tenth of a degree apart. That is about the distance of one-fifth of a full moon.
If weather permits, they should be easy to see just after sundown. This just-in-time-for-Christmas sight promises to be one of the greatest of Great Conjunctions. What makes this modern Great Conjunction different is that it is happening at nighttime. The last time that happened was almost 800 years ago.
Saturn and Jupiter have been getting closer in the sough-southwest sky for weeks. Jupiter, which is bigger and closer to Earth, is much brighter. The two planets might look like one body if viewed with eyes alone. If sky watchers use telescopes they should be able to see the planets as separate. Saturn will be the smaller, less-bright body at Jupiter's upper right.
Even though they appear close, more than 730 million kilometers of space lies between them. Observers using telescopes will not only see Jupiter and Saturn in the same field of view, but also some of their brightest moons. Their next close pairing will happen on March 15, 2080.
1. What do astronomers think of planets getting close to each other?| A．Controllable. | B．Unimaginable. |
| C．Common. | D．Dangerous. |
| A．The time when it takes place. |
| B．The part of sky where it happens. |
| C．The distance between the two planets. |
| D．The brightness of the two planets. |
A． | B． |
C． | D． |
| A．Two Planets Reach Especially near Earth |
| B．Jupiter and Saturn Come Together in the Night Sky |
| C．Conjunctions of Planets Excite Astronomers |
| D．Good Chances to Observe Jupiter and Saturn Appear |
6 . There are many therapies (疗法) for depression, including medical treatment, psychotherapy and talk therapy. Having a range of treatment choices is a good idea because no single treatment works equally well for each of millions of sufferers. Choosing the most suitable treatment is important to them. Now researchers say a new therapy proven to relieve depression should be added to the established treatments. It's called nature therapy. "Interacting with nature can have positive effects on those with depression," says Ethan Kross, PhD, an expert who has studied the nature depression link.
A little exposure to nature helps all of us get our energy back, and it may have special benefit for those who are depressed.“It seems that, from our work, the restorative effect of nature seems to be stronger for individuals with depression," says Marc Berman, PhD, an assistant professor of psychology at the University of Chicago. That might be because they feel mentally exhausted, and being in nature re energizes them. However, Dr Berman has a strong warning. “We're not arguing that interacting with nature should replace clinically proven treatments for depression," he says, “Nor should those with clinical depression try to treat themselves.”
However, Berman and others say, interactions with nature could serve as a very effective supplementary treatment. Compared to adults with depression walking for 50 minutes in an urban setting, those who took a 50 minute walk in a natural setting were less depressed and had better memory skills.
Why does nature hold this special effect? Berman says, “In a natural environment, we can choose to think or not, and this choice is believed to help us rest our brains. You can then pay attention later, when you need to.”He adds, “It gives people more ability to concentrate, which is a big problem for those with depression. ”Nature provides an effective setting for resting our brains, unlike urban setting. Even in the most peaceful urban environment, you have to pay attention to such things as traffic and stoplights.
1. What can we learn about depression therapies from paragraph 1?| A．They focus on physical activity. |
| B．They pay no attention to interactions. |
| C．They mainly depend on natural environment. |
| D．They need to be tailored to different patients. |
| A．By making them feel energetic. | B．By reminding them to rest in time. |
| C．By taking the place of clinic treatment. | D．By covering up their mental problems. |
| A．Additional. | B．Traditional. | C．Controversial. | D．Essential. |
| A．An urban setting of restoring energy. |
| B．The positive role of nature in treating depression. |
| C．The popularity of using multiple ways to treat diseases. |
| D．An effective replacement of clinical therapy for depression. |
7 . American billionaire Elon Musk has demonstrated a technology designed to use a computer chip inside the head to control the brain. During a video demonstration on Friday, Musk provided details about the system, called Neuralink.
Musk says he hopes the technology can be used to treat neural disorders and help spinal injury victims regain body movement. Musk also believes the system could be used in the future to improve intelligence to help humans keep up with supercomputers and artificial intelligence (AI) technology.
During the show, Musk showed off a model of the Neuralink device. It is about 23 millimeters wide. It is designed to be implanted into a person's skull. Small wires would connect the device directly to the brain.
The Neuralink system is currently being tested in pigs, with plans to seek government approval for human testing sometime in the future.
A pig named Gertrude was also shown during the show. Musk explained that Gertrude had a Neuralink chip inside its head. The device is meant to record nerve activity in the pig's nose and mouth.
Musk said the company had three pigs, each with two chips. He described the animals as "healthy, happy and indistinguishable from a normal pig." Musk said the company was able to predict with "high accuracy" a pig's leg movement on a running machine using data from the chip.
Musk noted that Neuralink first wants to use the device on people with severe spinal cord injuries to help them talk and move using their brain waves. He said he is hopeful that, in the long term, those people could regain "full-body motion."
Some neuroscientists not linked to the company said the presentation suggested Neuralink had made great progress with the technology. However, they warned that many more studies will be needed to test the long-term success of such devices.
1. What good can the Neuralink device do to the disabled?| A．Making them think clearly. |
| B．Treating their diseases successfully. |
| C．Having them keep up with supercomputers. |
| D．Helping them to move again. |
| A．Normal. | B．Active. | C．Nervous. | D．Intelligent. |
| A．it has been a great success. |
| B．it will succeed very soon. |
| C．it has a long way to go. |
| D．It needs support from new theories. |
| A．There Will Be Great Progress in Brain Science. |
| B．Musk Shows Technology Linking Computer to Brain. |
| C．Three Pigs Are being Tested Instead of Human Beings. |
| D．The Disabled Will Receive Better Treatment in the future. |
