1 . Running is often tiring and a lot of hard work, but nothing beats the feeling you get after finishing a long workout around the track.
But while it’s long been believed that endorphins (内啡肽) —chemicals in the body that cause happiness—are behind the so-called “runner’s high”, a study suggested that there may be more to this phenomenon than we previously knew.
According to a recent study published by a group of scientists from several German universities, a group of chemicals called endocannabinoids (内源性大麻素) may actually be responsible for this familiar great feeling.
To test this theory, the scientists turned to mice. Both mice and humans release high levels of endorphins and endocannabinoids after exercise. After exercising on running wheels, the mice seemed happy and relaxed and displayed no signs of anxiety. But after being given a drug to block their endorphins, the mice’s behavior didn’t seem to change. However, when their endocannabinoids were blocked with a different drug, their runners’ high symptoms seemed to fade.
“The long-held notion of endorphins being responsible for the runner’s high is false. Endorphins are effective pain relievers, but only when it comes to the pain in your body and muscles you feel after working out,” Patrick Lucas Austin wrote on science blog Lifchacker.
Similar studies are yet to be carried out on humans, but it’s already known that exercise is a highly effective way to get rid of stress or anxiety. The UK’s National Health Service even prescribes (开药 方) exercise to patients who are suffering from depression. “Being depressed can leave you feeling low in energy, which might put you off being more active. Regular exercise can improve your mood if you have depression, and its especially useful for people with mild to moderate (中等的) depression,” it wrote on its website.
It seems like nothing can beat that feeling we get after a good workout, even if we don’t fully understand where it comes from. At least if we’re feeling down, we know that all we have to do is to put on our running shoes.
1. What did scientists from German universities recently discover?A.Working out is a highly effective way to treat depression. |
B.The runner’s high could be caused by endocannabinoids. |
C.Endorphins may contribute to one’s high spirits after running. |
D.The level of endorphins and endocannabinoids could affect one’s mood. |
A.To find what reduces the runner’s high symptoms. |
B.To see the specific symptoms of the runner’s high. |
C.To identify what is responsible for the runner’s high. |
D.To test what influences the level of endocannabinoids released. |
A.Effect. | B.Goal. | C.Opinion. | D.Question |
A.They can help ease depression symptoms. |
B.They are the best way to treat depression. |
C.They only work for those with serious depression. |
D.They can help people completely recover from depression. |
6 . Climate change disproportionately affects the world’s most vulnerable people, particularly poor rural communities that depend on the land for their livelihoods and coastal populations throughout the tropics. We have already seen a chain of tough suffering that results from extreme weather events, such as hurricanes, floods, droughts, wildfires, and more.
For remedies, advocates and politicians have tended to look toward cuts in fossil-fuel use or technologies to capture carbon before it enters the atmosphere—both of which are crucial. But this focus has overshadowed the most powerful and cost-efficient carbon capture technology in the world. Recent research confirms that forests are absolutely essential in reducing climate change, thanks to their ability to absorb and isolate carbon. In fact, natural climate solutions such as conservation and restoration of forests, along with improvements in land management, can help us achieve 37 percent of our climate target of limiting warming to a maximum of two degrees Celsius above preindustrial levels, even though they currently receive only 2.5 percent of public climate financing.
Forests’ power to store carbon dioxide is staggering: one tree can store an average of about 48 pounds in one year. Intact(完整的)forests could take in the CO2 emissions of some entire countries.
For this reason, policymakers and business leaders must create and enforce policies to prevent deforestation, foster, reforestation of degraded land, and promote the sustainable management of standing forests in the fight against climate change. Protecting the world’s forests ensures they can keep performing essential functions such as producing oxygen, filtering water and supporting biodiversity. Not only does the world’s entire population depend on forests to provide clean air, clean water, oxygen and medicines, but 1.6 billion people also rely on them directly for their livelihoods.
Unfortunately, a huge amount of forest continues to be converted into agricultural land to produce a handful of resource-intensive commodities - despite zero-deforestation commitments from companies and governments. So now is the time to increase forest protection and restoration. This action will also address a number of other pressing global issues. For example, in less developed, rural areas - especially in the tropics - community-based forest-management programs can forge pathways out of poverty. In the Peten region of Guatemala, for instance, community-managed forests boasted a near-zero deforestation rate from 2000 through 2013, as compared with 12 percent in nearby protected areas and buffer(缓冲)zones. These communities have built low-impact, sustainable forest-based businesses that have stimulated the economy of the region enough to fund the creation of local schools and health services. Their success is especially noticeable in a location where, outside these community-managed zones, deforestation rates have increased 20-fold.
1. Which of the following statements about natural climate solutions is true according to the passage?A.They are the only effective strategies available to address the climate change. |
B.They pale in comparison with the reduction in fossil-fuel use or technologies. |
C.They can and should play a more important role in cutting carbon emissions. |
D.They manage to limit warming to two degrees Celsius above pre-industrial levels. |
A.documented | B.incredible |
C.unsteady | D.negligible |
A.The policies to prevent deforestation have borne fruit. |
B.Developed countries are hit the hardest by climate change. |
C.Economic growth contributes a lot to reducing deforestation. |
D.Some governments fail to keep their promises to preserve forests. |
A.Keeping forests undamaged can go a long way toward saving the planet. |
B.A high-tech climate fix is required to dramatically lessen global warming. |
C.Governments should work together with businesses to stop deforestation. |
D.Sustainable management of forests is crucial in powering regional development. |
Teaching in Front of a Camera
Wageningen University is keen on developing forms of education that reach people all over the world. The basics of the course topics are covered in short films and three-minute to seven-minute presentations
“The online Master’s programmes are quite different from the large scale MOOCs(在线课程),” explains Busstra. In the Master’s courses, the short “knowledge clips” dealing with the essential topics
The investment
Hi, everyone.
Traditionally,
Of course, the events of 2020 haven’t shown a lot of respect for our traditions. In a year of so much tragedy, it can be tough to give thanks when you’re doing your best to get by. And far too many of us will have to gather around a table with an empty chair, if we were able to gather together at all.
One thing, though, we can say about 2020 is that it forced us all to cherish what is most important, what’s most meaningful in our lives. To stop taking things for granted,
Throughout this challenging year, I’ve been moved, again and again, by the sacrifices so many were willing to make on behalf of others. The healthcare professionals who risked their lives to save ours. The workers who have kept our lights on and our shelves stocked, always essential to our economy, but finally
These are exactly the leaders Michelle and I started our Foundation to support. We always thought they
What we learned in 2020 is that these emerging leaders aren’t just building a brighter future, they’re safeguarding our present. In hard times, they are the ones who’ve given me solace. It’s
Merry Christmas and Happy Holidays, everybody.
—Quoted from Barack Obama’s Christmas speech in 2020
10 . You’re running late for work and you can’t find your keys: What’s really annoying is that in your search, you pick up and move them without realizing. This may be because the brain systems involved in the task are working at different speeds, with the system responsible for perception(感知)unable to keep pace.
So says Grayden Solman and his colleagues at the University of Waterloo in Ontario, Canada. To investigate how we search, Solman’s team created a simple computer-based task that involved searching through a pile of colored shapes on a computer screen. Volunteers were instructed to find a specific shapes as quickly as possible, while the computer monitored their actions.“Between 10 and 20 percent of the time, they would miss the object,”says Solman, even though they picked it up.“We thought that was remarkably often.”
To find out why, the team developed a number of further experiments. To check whether volunteers were just forgetting their target, they gave a new group a list of items to memorize before the search task, which they had to recall afterwards.
The idea was to fill each volunteer’s“memory load”,so that they were unable to hold any other information in their short-term memory. Although this was expected to have a negative effect on their performance at the search task, the extra load made no difference to the percentage of mistakes volunteers made.
To check that the volunteers were paying enough attention to the items they were moving, Solman’s team created another task involving a pile of cards marked with shapes that only became visible while the card was being moved. Again, they were surprised to see the same level of error, says Solman. Finally, the team analyzed participants’ mouse movements as they were carrying out a similar search task. They discovered that volunteers’ movements were slower after they had moved and missed their target.
Solman’s team propose that the system in the brain that deals with movement is running too quickly for the visual system to keep up. While you are searching around a messy house to find your keys, you might not be giving your visual system enough time to work out what each object is. Since time can be costly, sacrificing accuracy on occasion for speed might be beneficial overall, Solman thinks.
The slowing of mouse movements suggests that at some level the volunteers were aware that they had missed their target, a theory that is backed up by other studies that show people tend to slow down their actions after they have made a mistake, even if they don’t consciously realize the mistake.
1. What conclusion has Solman drawn from the first task?A.More volunteers are needed to confirm the findings. |
B.It happens very often that people miss what they intend to find. |
C.Computers make negative effects on how people perform at the task. |
D.Targets tend to be forgotten after people search for 10 minutes or more. |
A.Cards marked with shapes may become a source of distraction. |
B.Fewer errors will be made if people are forbidden to move cards. |
C.People may be absent-minded even when they are moving something. |
D.Volunteers prefer to use a mouse to control the objects on the computer screen. |
A.Mistakes will cause people to reduce the speed. |
B.Our visual system can’t keep up with the brain system. |
C.The faster people move, the more mistakes they will make. |
D.People’s actions are independent of the mistakes they make. |
A.Better memory, worse search |
B.Accuracy speaks louder than speed |
C.Hurry up, or you will make mistakes |
D.Slow down your search to find your keys |