By now it’s almost common knowledge that spending time in nature is good for you. Areas with 【小题1】(many) trees tend to be less polluted, so spending time there allows you to breathe easier. Spending time outdoors contributes to good health, with blood pressure and stress 【小题2】(reduce), and seems to motivate people 【小题3】(exercise) more.

A survey showed that people 【小题4】spend 2 hours in nature — either all at once or totaled over several shorter 【小题5】(visit) — were more likely to report good health and psychological well-being than those with no nature 【小题6】(expose). Remarkably, the researchers found that less than two hours offered no significant benefits. The two-hour benchmark (临界值) 【小题7】(apply) to men and women, to older and younger folks and so on. Even people【小题8】long-term illnesses or disabilities benefited from time 【小题9】(spend) in nature — as long as it was at least 120 minutes per week.

While the findings are based on 【小题10】tremendous number of people, scientists caution that it’s really just a correlation. Nobody knows why or how nature has this benefit or even if the findings will stand up to stricter investigation.

Exercise could not only benefit your body, but also improve your memory, researchers found 【小题1】(recent).

In their paper, researchers in the United States and Japan 【小题2】(introduce) their experiment and conclusion.

Scientists invited 36 volunteers who were in their early 20s to do 10 minutes of light exercise before taking a memory test in which they 【小题3】(show) pictures like broccoli (西兰花) or picnic baskets and asked to recall them later. The same experiment was repeated with the same group of volunteers without exercising. “The memory task really was quite 【小题4】(challenge),” said Michael Yassa, co-author of the study. “ We used very similar items to see if they would remember whether it was this exact picnic basket versus that picnic basket, 【小题5】can make the test results more intuitive (直观的). ”

In order to find the reason 【小题6】there were some differences, researchers also scanned (扫描) brains of some of the participants during the experiment.

They found increased communication between parts involved in the storage and recollection of memories in brains of those 【小题7】had exercised.

This suggested that just 10 minutes of light exercise might have a positive effect 【小题8】memory power.

As all the volunteers in the experiment were relatively young, researchers are still working 【小题9】(look) at the influence of light exercise on older people. “Our main goal is to try to develop a best exercise way 【小题10】 can be used by older adults who might have disabilities,” said Yassa.

I’ve noticed many people having a cold, and it's not even officially fall yet. Why does the cold occur more frequently during the fall and winter【小题1】(month)? It’s actually not the cold weather 【小题2】 (it) that causes the cold. But rather, it is most likely to be caused by people spending 【小题3】 (much) time indoors close to each other, making it easier to spread the germs. This is another reason 【小题4】 children in day care or school are more likely to pick up the cold.

When I worked in a doctor’s clinic a few years back, it was one of the 【小题5】 (lead) reasons to visit the doctor in fall and winter. 1 billion people suffer from the cold each year. As a result, school absence 【小题6】 (report) frequently, with around 22 million days annually.

How can you avoid getting a cold? Among the commonly 【小题7】 (recognize) tips, washing your hands is 【小题8】 most important one. The cold is spread either by directly touching infected secretions (分泌物), or by taking 【小题9】 the airborne particles(悬浮粒子). Also, cold and flu viruses get into the body via the eyes, noses, or mouth. So, try 【小题10】 (avoid) touching your face, especially without first washing your hands.