Suppose you become a leader in an organization. It's very likely that you'll want to have volunteers to help 

with the organization's activities. To do so, it should help to understand why people undertake volunteer work and

what keeps their interest in the work.

       Let's begin with the question of why people volunteer. Researchers have identified several factors that 

motivate people to get involved. For example, people volunteer to express personal values related to unselfishness, 

to expand their range of experiences, and to strengthen social relationships. If volunteer positions do not meet these 

needs, people may not wish to participate. To select volunteers, you may need to understand the motivations of the 

people you wish to attract.

         People also volunteer because they are required to do so. To increase levels of community service, some 

schools have launched compulsory volunteer programs. Unfortunately, these programs can shift people's wish of

participation from an internal factor (e.g., “I volunteer because it's important to me”) to an external factor (e.g., “I

volunteer because I'm required to do so”). When that happens, people become less likely to volunteer in the future.

People must be sensitive to this possibility when they make volunteer activities a must.

          Once people begin to volunteer, what leads them to remain in their positions over time? To answer this 

question, researchers have conducted follow-up studies in which they track volunteers over time. For instance, one 

study followed 238 volunteers in Florida over a year. One of the most important factors that influenced their 

satisfaction as volunteers was the amount of suffering they experienced in their volunteer positions. Although this

result may not surprise you, it leads to important practical advice. The researchers note that attention should be 

given to “training methods that would prepare volunteers for troublesome situations or provide them with 

strategies for coping with the problem they do experience”.

         Another study of 302 volunteers at hospitals in Chicago focused on individual differences in the degree to 

which people view “volunteer” as an important social role. It was assumed that those people for whom the role of 

volunteer was most part of their personal identity would also be most likely to continue volunteer work. 

Participants indicated the degree to which the social role mattered by responding to statements such as 

“Volunteering in Hospital is an important part of who I am.” Consistent with the researchers' expectations, they

found a positive correlation (正相关) between the strength of role identity and the length of time people continued 

to volunteer. These results, once again, lead to concrete advice: “Once an individual begins volunteering, 

continued efforts might focus on developing a volunteer role identity.... Items like T-shirts that allow volunteers to 

be recognized publicly for their contributions can help strengthen role identity”.

    Bill Gates recently predicted that online learning will make place-based colleges less significant, and five years from now, students will be able to find the best lectures in the world online. I applaud Mr. Gates. But what's taking us so long?

    As early as 1997, MIT(麻省理工) decided to post videos of all university lectures online. for free, for all people. But today, how many students have you met who mastered advanced mathematics or nuclear physics from an MIT online video? Unfortunately, the answer is not many. The problem is the poor quality of online education websites and the experience they provide to students. Those who go to the MIT website and watch courses online are surely very smart people, but it's not like playing a video game such as World of Warcraft. Only the most ardent students, those who are highly motivated, will devote themselves to studying these boring online videos.

    The real question is why we aren't spending more to develop better online education platforms. Where is the Avatar of education? Think about this. The market for Hollywood films per year is worth around 30 billion USD. Education in the world is a trillion-dollar-a-year market, hundreds of times bigger than Hollywood movies. Yet the most expensive digital learning system ever built cost well under 100 million dollars.

    Bill Gates' prediction is going to happen. There is no doubt about it. But it will only happen when we create high level educational content and experiences that engage and excite more than has ever been possible in the real world.

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C

Plastic-Eating Worms

    Humans produce more than 300 million tons of plastic every year. Almost half of that winds up in landfills(垃圾填埋场), and up to 12 million tons pollute the oceans. So far there is no effective way to get rid of it, but a new study suggests an answer may lie in the stomachs of some hungry worms.

    Researchers in Spain and England recently found that the worms of the greater wax moth can break down polyethylene, which accounts for 40% of plastics. The team left 100 wax worms on a commercial polyethylene shopping bag for 12 hours, and the worms consumed and broke down about 92 milligrams, or almost 3% of it. To confirm that the worms' chewing alone was not responsible for the polyethylene breakdown, the researchers made some worms into paste(糊状物) and applied it to plastic films. 14 hours later the films had lost 13% of their mass — apparently broken down by enzymes (酶) from the worms' stomachs. Their findings were published in Current Biology in 2017.

    Federica Bertocchini, co-author of the study, says the worms' ability to break down their everyday food — beeswax — also allows them to break down plastic. ＂Wax is a complex mixture, but the basic bond in polyethylene, the carbon-carbon bond, is there as well, ＂she explains, ＂The wax worm evolved a method or system to break this bond. ＂

    Jennifer DeBruyn, a microbiologist at the University of Tennessee, who was not involved in the study, says it is not surprising that such worms can break down polyethylene. But compared with previous studies, she finds the speed of breaking down in this one exciting. The next step, DeBruyn says, will be to identify the cause of the breakdown. Is it an enzyme produced by the worm itself or by its gut microbes(肠道微生物)?

    Bertocchini agrees and hopes her team's findings might one day help employ the enzyme to break down plastics in landfills. But she expects using the chemical in some kind of industrial process — not simply ＂millions of worms thrown on top of the plastic.＂

    It was a Sunday and the heavy storm had lasted all night. The morning after the storm, though, was beautiful: blue skies, warm air and a calm, inviting sea touching the shore gently.

    My father realized it was a good day for fishing and invited my sister and me to go with him. I was only 14 and fishing had never been my thing, but I decided to go all the same. I'm so glad I did.

    On the road to the harbour we could see the terrible destruction on the coast, but the harbour itself was in fairly good shape. After all, it was protected by the arms of a bay that had only one tiny channel to the sea. As we got on board, we noticed two big hums(脊背)in the distance.

On approaching them, we saw it was a mother whale with her baby. We couldn't believe it –—there aren't any whales along the coast here. The storm must have driven them across the ocean into the bay, in which the still water was so badly polluted that nothing could survive.

The little baby whale—-actually as big as our boat—-was obviously stuck and could not move. The mother dived under the water and came up suddenly, making big whirlpools(漩涡)and waves. “She's trying to help her baby, but on the wrong side,” my father said. At this point, my father moved our boat in a semicircle to the other side and, heading the boat towards the baby whale, pushed it gently. With our several gentle pushes the big hump turned over and disappeared under water. Then it swam up right beside its mum. They struggled in their desperate attempts to escape but missed the exit and started heading in the wrong direction. We hurried up to the whales and tried to lead them towards the bay channel. Slowly, they let us lead them, sometimes rising from the water right beside us to breathe –—and to give us a trusting(信任的) look with those huge eyes. Once they hit their first part of clean water flowing straight from the sea, the mum gave us a wave with her tail and off they swam into the distance.

    In the excitement it had felt like only a few minutes, but we had been with those wonderful animals for almost an hour and a half. That was the simple and lasting beauty of the day. Nearly four decades later, I still look back fondly to that golden day at sea.

    An international group of coffee experts has considered Ethiopia's coffee as the best in the world. Coffee is a top export of the country. But at home, it is seen as national pride. Ethiopians feel good about their coffee, and enjoying a drink with friends is a long tradition.

    International coffee experts travel the world to find the best coffee. They keep returning to Ethiopia. Some people say the climate produces quality beans. Morton Wenner is a coffee importer. He said, “Ethiopia has different ancient types of coffee. They are planted in places with perfect soil, perfect altitude, and climates that are really suitable for coffee processing, such as drying and things like that.”

    Finding the best quality beans is often an issue of taste. The process is known as cupping — tasting and comparing coffee from different roasted beans, grading and then pricing them.

    But before international experts come to taste, coffee beans are studied in small coffee laboratories. Helen Assefa, a lab technician, describes the process, “When the coffee comes to the lab, we assess its quality first by recording the details. Then we weigh the wetness level and screen the beans for analysis. After that we polish the coffee beans and taste the samples. At the end we check for imperfect beans.”

    Ethiopia is making big profits on its coffee reputation by exporting coffee to more than 120 countries. The country has an export income of more than $840 million a year. But not all the best coffee leaves Ethiopia. Forty percent of the coffee grown in the country stays there. It remains an important part of everyday life at work, at home and at ceremonies just to celebrate that special cup.

    NEW HAVEN, Connecticut—A surprise awaited students in Yale who showed up for Professor Laurie Santos's class. They got slips of paper that said, "No class today." There was only one rule for the students' unexpected free time—They were not allowed to study, but to relax. Since exams and papers were coming up, everyone was tired and stressed. At this moment they were touched. With around applause, nine students hugged Santos, and two burst into tears.

    Yet, cancelling class was not just a break. It was also a challenge, as she was asking them to stop worrying about their grades, even if it was just an hour. One student went to the Yale University Art Gallery for the first time in her four years at Yale. A group of students went to a recording studio and played a new song. More people were outside, and more were smiling. That's why about 1, 200 students were taking Santos's class, called "Psychology and the Good Life," the largest class in Yale's 317-year history. Even non-Yale students had the chance to take Santos's class. It was offered as an online course and she immediately became an Internet hit.

    Skyler Robinson, one of her students, was at a loss for a while about what to do during his break, and then decided to take a nap. "It was a great nap," he commented. Santos designed the class after she realized that her students kept busy through long days that seemed far more depressing and joyless than her own college years. "They feel they're in this crazy rat race. They're working so hard that they can't take a single hour off. That's awful."

    The ideas behind the class are simple. Santos said, "It is the hope that science can help students find peace among all the stresses and difficulties they face at college." The lessons include showing more gratitude, performing acts of kindness and increasing social connections. The students really wanted to learn to lead a happy life in a science -driven way. Santos also noted the psychological happening of "mis-wanting", which led people to work towards the wrong goals in life.

    One week, Santo asked students to exercise. Another week, she wanted them to get more sleep. They worked hard to keep some new habits. Social science research led to many new understandings of how people find happiness. She thinks her class can change Yale, or rather, not just Yale.