Exercise may help to safeguard the mind against depression through previously unknown effects on working muscles, according to a new study involving mice.

    Mental health experts have long been aware that even mild, repeated stress can contribute to the development of depression and other mood disorders in animals and people. Scientists have also known that exercise seems to cushion against depression. But precisely how exercise, a physical activity can lessen someone's risk for depression, a mood state, has been mysterious. So for the new study, researchers at the Karolinska Institute in Stockholm studied the brains and behavior of mice in a complicated and novel fashion.

    We can't ask mice if they are feeling cheerful or in low spirits. Instead, researchers have pictured certain behaviors that indicate depression in mice. If animals lose weight, stop seeking out a sugar solution when it's available — because, probably, they no longer experience normal pleasures — or give up trying to escape from the cold-water zone just freeze in place, they are categorized as depressed. And in the new experiment, after five weeks of frequent but low-level stress, such as being lightly shocked, mice displayed exactly those behaviors. They became depressed.

    The scientists could then have tested whether exercise blunts (延缓) the risk of developing depression after stress by having mice run first. But, frankly, from earlier research, they wanted to know how, so they bred pre-exercised mice. A wealth of earlier research by these scientists and others had shown that aerobic exercise, in both mice and people, increases the production within muscles of an enzyme (酶) called PGC-1alpha. The Karolinska scientists suspected that this enzyme somehow creates conditions within the body that protect the brain against depression. Then, the scientists exposed the animals, which without exercising, were in high levels of PGC-1alpha to five weeks of mild stress. The mice responded with slight symptoms of worry. But they did not develop depression. They continued to seek out sugar and fought to get out of the cold-water zone. Their high levels of PGC-1alpha appeared to make them depression-resistant. Finally, to ensure that these findings are relevant to people, the researchers had a group of adult volunteers complete three weeks of frequent endurance training, consisting of 40 to 50 minutes of moderate cycling or jogging. The scientists conducted muscle biopsies (活体检查) before and after the program and found that by the end of the three weeks, the volunteers' muscle cells contained substantially more PGC-1alpha than at the study's start. The finding of these results, in the simplest terms, is that “you reduce the risk of getting depression when you exercise,” said Maria Lindskog, a researcher at the Karolinska Institute.

    Meeting people from another culture can be difficult. From the beginning, people may send the wrong signal. Or they may pay no attention to signals from another person who is trying to develop a relationship.

    Different cultures emphasize the importance of relationship building to a greater or lesser degree. For example, business in some countries is not possible until there is a relationship of trust. Even with people at work, it is necessary to spend a lot of time in "small talk", usually over a glass of tea, before they do any job. In many European countries, like the UK or France, people find it easier to build up a lasting working relationship at restaurants or cafe rather than at the office.

    Talk and silence may also be different in some cultures. I once made a speech in Thailand. I had expected my speech to be a success and start a lively discussion, instead there was an uncomfortable silence. The people present just stared at me and smiled. After getting to know their ways better, I realized that they thought I was talking too much. In my own culture, we express meaning mainly through words, but people there sometimes feel too many words are unnecessary.

    Even within Northern Europe, cultural differences can cause serious problems. Certainly, English and German cultures share similar values, however, Germans prefer to get down to business more quickly. We think that they are rude. In fact, this is just because one culture starts discussions and makes decisions more quickly.

    People from different parts of the world have different values, and sometimes these values are quite against each other. However, if we can understand them better, a multicultural environment will offer a wonderful chance for us to learn from each other.

    James Cleveland Owens was the son of a farmer and the grandson of black slaves. His family moved to Cleveland when he was 9. There, a school teacher asked the youth his name.

    "J.C. "he replied.

    She thought he had said "Jesse", and he had a new name.

    Owens ran his first race at age 13. After high school, he went to Ohio State University. He had to work part time so as to pay for his education. As a second year student, in the Big Ten games in 1935, he set even more records than he would in the Olympic Games a year later.

    A week before the Big Ten meet, Owens accidentally fell down a flight of stairs. His back hurt so much that he could not exercise all week, and he had to be helped in and out of the car that drove him to the meet. He refused to listen to the suggestions that he give up and said he would try. He did try, and the results are in the record book.

    The stage was set for Owens' victory at the Olympic Games in Berlin the next year, and his success would come to be regarded as not only athletic but also political. Hitler did not congratulate any of the African American winners.

    "It was all right with me," he said years later. "I didn't go to Berlin to shake hands with him, anyway."

    Having returned from Berlin, he received no telephone calls from the president of his own country, either. In fact, he was not honored by the United States until 1976, four years before his death.

    Owens' Olympic victories made little difference to him. He earned his living by looking after a school playground, and accepted money to race against cars, trucks, motorcycles and dogs.

    "Sure, it bothered me," he said later. "But at least it was an honest living. I had to eat."

    In time, however, his gold medals changed his life. "They have kept me alive over the years, "he once said." Time has stood still for me. That golden moment dies hard."

    “Who made your T-shirt?” A Harvard University student raised that question. Piertra Rivoli, a professor of business, wanted to find the answer. A few weeks later, she bought a T-shirt and began to follow its path form Texas cotton, to Chinese factory and to charity bin (慈善捐赠箱). The result is an interesting new book, The Travels of a T-shirt in the Global Economy.

    Following a T-shirt around the world in a way to make her point more interesting, but it also frees Rivoli from the usual arguments over global trade. She goes wherever the T-shirt goes, and there are surprises around every corner. In China, Rivoli shows why a clothing factory, even with its poor conditions, means a step towards a better care for the people who work there. In the colorful used-clothing markets of Tanzania, she realizes that, “it is only in this final stage of life that the T-shirt will meet a real market,” where the price of a shirt changes by the hour and is different by its size and even color. Rivoli's book is full of memorable people and scenes, like the noise, the bad air and the “muddy sweet smell of the cotton,” she says. “Here in the factory, Shanghai smells like shallow water Texas.”

    Rivoli is at her best when making those sorts of unexpected connections. She even finds one between the free traders and those who are against globalization. The chances opened up by trade are vast, she argues, but free markets need the correcting force of politics to keep them in check. True economic progress needs them both.

    People generally tend to pick out the best-looking fruits and vegetables when shopping for produce, but Canadian supermarket chain Loblaws is attracting customers with badly-shaped and faulty produce at the price of 30% lower than normal-looking ones.

    A trial run of the ugly food line, named "Naturally Imperfect", began with only apples and tomatoes to choose from. Consumer demand has been so huge that Loblaws is going to introduce more unsightly vegetables and fruit options like onions and mushrooms. The line is available at other stores, including Real Canadian Superstore and Your Independent Grocer.

    All the produce that will be sold through Naturally Imperfect would otherwise have been used in juices, sauces, or soups, or have not been harvested at all. The director Dan Branson explained that this program benefited both food producers who would otherwise have to let abnormal harvest go to waste, and consumers who could buy fresh produce at low prices. And he was right, given how popular the line has become.

    "It really went well beyond our expectation," Branson said. "I think it really spoke to the fact that Canadians are out there really looking for some options."

    Of course, Canadians know that beauty is more than skin deep, but they also recognize that they can get the same flavor and nutritional benefits in spite of appearances. The positive response to the initial offering of apples and potatoes showed the opportunity to expand the line and offer more options at a greater price to Canadian families.

    "If you grow produce in your backyard, there will be a lot of produce that won't look as pretty as what you will see in a grocery store," said Branson. "And nature doesn't grow everything perfectly. I'd like to think if somebody were to take a No Name Naturally Imperfect apple, put right beside a No.1 apple, close their eyes and eat them, there would be no difference."