1 . When it comes to figuring out the link between well-being and access to nature, there are big confusing factors. To begin with, what is psychological(心理的)well-being? The World Health Organization defines(下定义)mental health as “a state of well-being in which an individual realizes his or her own abilities, can deal with the normal stresses of life, can work productively and is able to make a contribution to his or her community”. That is hard to quantify.
Then there is the question of what “access to nature” means. Some studies measure passive access, or how much green space is available in someone’s local area. Others look at active access, which is the actual exposure a person gets to green space. That makes it difficult to compare results and build a coherent(协调的)picture.
A few researchers have tried to assess what the proper dose(剂量)of nature might be. A 2019 study involving almost 20,000 participants in England concluded that at least 120 minutes a week of recreational(消遣的)nature contact was connected with good health or well-being. The team, led by Mathew White, found that the effect peaks at between 200 and 300 minutes a week, with people reporting no further gain after that.
What exactly this means for you—or any individual—is unclear. As other studies indicate, the mental health benefits a person gets from access to nature are likely to be influenced by many factors, including age, gender, personality features, personal preferences and socio-economic status. Your culture matters too—and, so far, most research into the well-being effects of nature has been done in Western societies.
1. Which of the following might mean mental health according to WHO?| A．Ignoring ones’ own abilities. | B．Complaining about stresses. |
| C．Communicating effectively. | D．Having high productivity. |
| A．50 minutes. | B．150 minutes. | C．250 minutes. | D．350 minutes. |
| A．Studies haven’t provided any results so far. |
| B．Studies haven’t considered all the factors. |
| C．Studies were only done in Western societies. |
| D．Studies have misled the public over the results. |
| A．Why does nature affect health? | B．Who does nature influence? |
| C．How much nature do I need? | D．How does nature benefit people? |
2 . 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 |
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. |
