3 . Some colors that people see late at night could cause signs of the condition mental health experts call clinical depression. That was the finding of a study that builds on earlier study findings. They show that individuals who live or work in low levels of light overnight can develop clinical depression.

Doctors use the words “clinical depression” to describe severe form of depression. Signs may include loss of interest or pleasure in most activities, low energy levels and thoughts of death or suicide.

In the new study, American investigators designed an experiment that exposed hamsters to different colors. The animals were separated into 4 groups. One group of hamsters was kept in the dark during their nighttime period. Another group was placed in blue light, a third group slept in white light. While a fourth was put in red light. After four weeks, the researchers noted how much sugary water the hamsters drank. They found that the more depressed animals drank the less amount of water.

Randy Nelson, who heads the Department of Neuroscience at Ohio State University, says animals that slept in blue and white light appeared to be the most depressed. “What we saw is these animals didn’t show any sleep disruptions at all but they did have messed up circadian clock genes (生物钟基因)and they did show sign of depression whereas if they were in the pale red light, they did not.” He says there’s a lot of blue in white light, which explains why the blue light and white light hamsters appear to be more depressed than the hamsters that see red light or darkness.

Mr Nelson has suggestions for people who work late at night, or those who like to stay up late.

“My recommendation is if you are just living a typical mostly active life during the day, mostly inactive at night, you need to limit exposure to TVs which are quite bluish in the light they give off and computer screens and things like that. You can get filtered glass, you can get filters (过滤器) on your computer screen and filters on your eReaders to put it more in the reddish light.”

6 . For many of us, summertime means road trips to the beach or mountains, or at the very least some additional dust on the outside of our vehicle. The extra dirt leads us to do one of two things: wash our car in the driveway or head to the car wash. But which choice is better for the environment?

The main concerns with either choice are the amount of fresh water used and the types of chemicals used to get rid of the dirt. Both of these concerns can be closely monitored when washing the car at home, says Katy Gresh, spokeswoman for the Southwest Region of the Pennsylvania Department of Environmental Protection. She advises car owners to keep a set amount of water in a container for the entire wash. “You don’t want to leave the water running or use more than you need for the job,” she says. But even following this piece of advice comes with an environmental risk: Washing your car in the driveway gets the dirty water into drains (下水道).

“Drains are not made for treating waste.” says John Schombert, executive director of 3 Rivers Wet Weather. Even when car owners use natural soaps to wash their car, Schombert says they are probably ineffective in breaking down grease(油脂)anyway.

The commercial car wash knows full well the rules regarding wastewater in drains. According to the International Carwash Association (ICA), professional car washes must use special water treatment systems. These processes not only keep the dirty water out of drains and regular water treatment systems, but also work to reduce water usage at commercial facilities.

As experts point out, cleaning our car at home can use 100 gallons of water. Compare that to self-service car washes, which allow you to use only about 17 or 18 gallons of water. And most full-service car washes average about 30 to 45 gallons of water per vehicle.

7 . Gene therapy (基因治疗) is a revolutionary new technique for treating people with health problems. Up until very recently, the most commonly available methods for treating patients were either through drugs or operations. Gene therapy provides a third option for treatment by transforming or replacing cells with new genetic materials and instructions. Scientists can be very precise in the kinds of changes they make in patients.

Gene therapy works by using a delivery system, such as a virus, to enter a patient's body. Once inside the body, the virus combines with a host cell and delivers the new DNA. The proteins then begin to repair the affected cells. New techniques have focused on removing cells from the patients and transforming them outside the body before reintroducing them to the patients.

The two types of gene therapy are called somatic and germline. Somatic therapy refers to changing or replacing a body cell. In this case, the treatment is restricted to the patient only. This will not affect the patient's future children because the patient's germ (生殖) cells are unaffected. In germline therapy, the patient germ cells are treated, which may affect the patient's future generation.This is highly controversial (有争议的) because it is not clear exactly how this might affect them and further generations. For this reason, many countries have passed laws that prohibit this kind of treatment.

Despite the promise of gene therapy, there are still many barriers that need to be overcome before it comes into widespread use. One of the issues is that the use of viruses to deliver DNA may actually cause unexpected problems in patients if the virus grows and attacks the body. Another problem is the nature of many diseases is very complex and spread throughout multiple genes. The use of gene therapy to change a single gene in the body would probably not be sufficient as a cure. Finally, the costs of gene therapy are high. Some gene therapy procedures may cost over$1 million to undertake and require specialized doctors and equipment.

8 . The past week was by no means an ordinary week,     1    .

This Monday, the topic was brought up again by my parents during dinner.     2    . Seeing my hesitant look, Mom patted me on my shoulder and said that I still had enough time to think about it, her smile encouraging me to do more research.

Later that evening, I turned to the Internet for help.     3    . As a science student, law could be a good choice. Business and computer science were also attracting me. No sooner had I noted down the majors one after another than I crossed them all off immediately, because what I wanted was a profession that could make a difference in people’s lives.

    4    . The moment “Role Models of Our Time” appeared on the screen, it caught my eye. The news story focused on superheroes-police officers, healthcare workers, deliverymen street cleaners-who guarded us selflessly to ensure our life ran normally. Suddenly, I realized my life's purpose-relieving pain and saving lives. And to pursue this call, I decided to specialize in medical science, just like my role models fighting against Covid-19 in Wuhan.

I jumped excitedly with joy at this idea.     5    , saying that they would be so proud to see me in white. Now, determined to become a healthcare worker, whenever I start my schoolwork, I know I am studying for a noble cause.

9 . Most people aren’t good at creative problem solving for two reasons: (1) They are not trained in how to be creative. (2) They don’t understand group strength well enough to harness (驾驭) their power to maximize group creativity.

A key element of creativity is applying existing knowledge to a new problem. The more people getting involved in solving it, the more knowledge there is to work on it. Unfortunately, research shows that the traditional brainstorming methods fail to achieve that goal. When groups get together to exchange ideas, they actually come up with fewer ideas overall than if they each had worked alone.

To fix this problem, you should consider the two stages of group problem-solving: divergence (分散) and convergence (集中). Divergence happens when the group considers as many different potential solutions as possible. Convergence happens when the various proposed solutions are evaluated and reduced to a smaller set of candidate solutions to the current problem.

The essential principle of group creativity is that individuals working alone diverge, whereas group members working together converge. In groups, once a member states a potential solution, that makes others think about the problem similarly. That is why groups working together diverge less than individuals working alone.

Therefore, be aware of when to diverge and when to converge. For example, early in the problem-solving process, have group members work alone to write down statements describing the problem. Then get them back to discuss their descriptions. The group discussion will lead everyone to accept one or a small number of these statements to work on — this is healthy convergence.

When starting to generate solutions, you again want divergence. Have people work alone to start. Then collect people’s initial ideas and send them around to others and allow the divergence to continue as everyone individually builds on the ideas of other members.

Finally, let the group discuss the resulting ideas. This discussion will gradually lead the group to converge on a small number of candidate solutions.

This simple method works effectively, because it respects what individuals and groups do best.

10 . Researchers from Stockholm University, the Institute for Future Studies, and the University of South Carolina teamed up to find out if generosity really pays off. The results, published in the Journal of Personality and Social Psychology, reveal that unselfish people tend both to have more children and earn higher salaries than selfish people.

“The result is clear in both the American and the European data. The most unselfish people have the most children and the moderately (适度地) unselfish receive the highest salaries. And we also find this result over time: the people who are most generous at one point in time have the largest salary,” explains Kimmo Eriksson, a researcher at the Centre for Cultural Evolution at Stockholm University and one of the authors of the study.

Previous psychological and sociological (社会学的) research has shown that selfless people feel happier and have better social relationships, but scientists can now see the benefits of generosity in other areas of life including income and fertility (生育能力).

“The results of this study showed that people generally have the correct expectation that selfish people have fewer children, but erroneously believe that selfish people will make more money. It is nice to see that generosity so often pays off in the long run says Pontus Strimling, a researcher at the Institute for Futures Studies and co-author behind the study.

The researchers believe that prosocial (亲社会的) behaviors help generous people in succeeding from an economic perspective. Although the study does not definitively answer this question, it makes sense that unselfish people, who tend to give their time and energy more willingly to help others would thrive (兴旺) in business relationships and teamwork settings. On the other hand, acting in self-interest has poorer outcomes including lower incomes.

Co-author, Brent Simpson of the University of South Carolina adds, Future research will have to explore deeper into the reasons why generous people earn more and look at whether the link between unselfishness, higher salaries, and more children also exists in other parts of the world.