It is said that if you want to stay young, sit down and have a good think. This is the research finding of a team of Japanese doctors, who say that most of our brains are not getting enough exercise — and as a result, we are growing old unnecessarily soon.

    Professor Taiju Matsuzawa wanted to find out why otherwise healthy farmers in northern Japan appeared to be losing their ability to think and reason at a relatively early age, and how the process of aging could be slowed down. With a team of colleagues at Tokyo National University, he set about measuring brain volumes of a thousand people of different ages and varying occupations. Computer technology enabled the researchers to obtain precise measurements of the volume of the front and side parts of the brain, which controls functions like eating and breathing, does not contract with age, and one can continue living without intellectual on economical faculties. Contraction of front and side parts — as cells die off — was observed in some subjects in their thirties, but it was still not evident in some sixty-and seventy-year-olds. Matsuzawa concluded from his tests that there is a simple way to the contraction normally connected with age — using the head.

    The findings show in general terms that contraction of the brain begins sooner in people in the country than in the town. Those least at risk, says Matsuzawa, are lawyers, followed by university professors and doctors. White collar workers doing routine work in government offices are, however, as likely to have shrinking (萎缩) brains as the farm worker, bus driver and shop assistant.

    Matsuzawa's findings show that thinking can prevent the brain from shrinking. Blood must circulate properly in the head to supply the fresh oxygen the brain cells need. “The best way to maintain, good blood circulation is through using the brain.” he says. “Think hard and engage in conversation. Don't rely on pocket calculators.”

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    I must have looked deep in thought, or as deep in thought as an 11-year-old man can, when my grandmother glanced up from her weeding to ask, "You have something on your mind, don't you?"

    "Yes, I was thinking that someday I want to be an Olympic speedskating champion like my hero, Eric Heiden, I want to be a doctor like my parents and I want to help children in Africa."

    I immediately knew I had confided in the right person when a knowing smile broke across her face. "Johann, of course! You can do anything you want to do!" she said simply. And with my grandmother's support, I set out to pursue my passions.

    14 years later, I was well ready to take hold of my first dream: becoming an Olympic champion. The Olympics in 1994 were in my home country, Norway. As I entered the Olympic stadium, I wasn't the best athlete, and many had doubts about my ability to perform well. But I had something special working for me. I had a woman in the first row who believed in me following my passions just as much as I did. For the first time ever, my grandmother was going to see me skate.

    It happened. Breaking a world record, I won the gold.

    As I stood on the podium(领奖台) that I had dreamed about my entire life, a curious question popped into my head. Why me? Why did I win, given all the other incredible competitors out there? The reason had to be more than a grandmother who shared a belief in her grandson's dream. The question led me to only one answer: because I wanted to make a difference in the world, and with all the media attention on my success, I could.

    I immediately knew what that difference had to be: hope in the lives of the children in Africa. Six months earlier, I'd been invited to Egypt as an ambassador for Olympic Aid.

    Last night, on my way home I stopped because of being attracted by some hamburgers at a fast food restaurant. On my way in, a homeless man approached me and asked, “Do you have any bottles lying around?” I knew he would recycle them for a few cents, but I didn't have any, so I said no. And again he asked, “Can you spare some change (零钱)?” I smiled, and said no again. He was very respectful; he smiled back and said, “OK, thank you.” Even though he didn't have anything, he was still in good spirits. From the way he spoke I could tell he was smart.

    Then I bought one hamburger and enjoyed my meal, but in the back of my mind I wondered whether the homeless man was hungry. After I finished my meal I decided to order another one for him. At this point I didn't know if he was still around, but I tried anyway.

    At the counter I ordered a hamburger and also a hot chocolate, because it was cold outside, and I thought it would help warm him up. They delivered me the hot chocolate first and as I waited for my hamburger, I noticed the homeless man was standing right beside me. I looked at him and smiled, “This hot chocolate is for you.”He replied like a gentleman,“Thank you so much. That's very kind of you.”

    I always believe no matter how hard up (缺钱) I am, there are always those who are worse off than I. When you help someone, it's not always about money, it's about love. The love you give today, someone might forget tomorrow. It doesn't matter. Love anyway, because the greatest thing you can give is love.

    Allan Guei, 18, was a star basketball player at Compton High School in the Los Angeles area before he graduated last month. His good grades made him eligible for an unusual competition: A free-throw contest in the Compton High gymnasium. The top prize: ＄40,000 in scholarship money.

    Guei, whose parents immigrated to the United States from the Ivory Coast, knew how much that financial aid could mean for his family. He was also feeling a fair share of pressure as students and teachers crushed into the gym to watch Guei and seven other randomly compete against each other.

    Guei won the free-throw contest by one basket and netted the ＄40,000. But it's what he did next that's truly astonishing.

In the weeks following the March free-throw competition, Guei learned that he'd scored a full-ride basketball scholarship to California State University—Northridge. NCAA(全国大学生体育协会)rules allowed Guei to accept the athletic scholarship and also keep most of the ＄40,000 he had won.

    But Guei couldn't stop thinking about the seven talented runners-up from the free-throw contest. They, too, had dreams and very real needs. So, he asked Principal Jesse Jones to make a surprise announcement at Compton High's graduation ceremony: Geui wanted to donate the ＄40,000 to the other seven students.

    “I've already been blessed so much and I know we're living with a bad economy, so I know this money can really help my classmates,” Guei said in a statement. “It was the right decision.”

    Guei elaborated on his decision to give the money away in an interview with ESPN(体育电视网): “I was already well taken care of to go to school, to go to university for free… I felt like they needed it more than I did.”

    Last year marked the 100th anniversary of the end of World War I. There were events around the world in memory of those who died in the conflict. We have picked out three of them inEuropean countries. Let's take a look.

    Belgium

    In a park, the famous Belgian artist Koen Vanmechelen had an exhibition called Coming World, Remember Me. The work consisted of 600,000 individual(个别的) clay sculptures, one for each person killed during the World War. In the center of the exhibition was a big egg made of clay, symbolizing a new world.

    UK

    In a small town called Aldridge, almost 100 houses in one street were covered with 24,000 poppies and statues of soldiers. They stood for the men from the area who had been' killed in the war. The flowers were chosen because of a poem written by the Canadian doctor John McCrea in 1915. They made people think of fields of blood.

    France

    The British artist Guy Denning arrived in La Feuille, a small town in the northwest of France, to stick life-size drawings of soldiers who never came back home. Armed with glue and a brush, Denning stuck his drawings carefully on walls. Before long 112 men, mainly young adults, were brought back to mind, if not to life.

    Picture this: You're searching the Internet and come across a website with interesting articles. Some are news stories. Their goal is to share information. Others only look like news stories. They're actually advertisements, or ads. The goal of an ad is to get you to buy something. How do you, the reader, tell the difference between a news story and an ad?

    Back when I was growing up, it was easier. We got most of our information from newspapers. Big news stories appeared on the front page, and ads were boxed off and clearly labeled. But on the Internet, the two are often presented together. It can be hard to tell which is which.

    That's why the research group I direct conducted a study. My research team showed kids like you the home page of a popular digital magazine. We asked them to tell us what was a news story and what was an ad.

    Most were great at identifying certain types of ads. "It has a coupon (优惠券) code, a big company logo, and the words 'limited time offer'," one student wrote about an ad on the site. So where did kids get stumped (难倒)？

    Some ads seem identical to real news stories. They have headlines and contain information. But they may also include the words "sponsored content". Sponsored means "paid for," and content refers to the information in the story. "Sponsored content" is a way of saying that something is an ad. Most kids in our study, even if they used the Internet often, didn't know this.

    Something sponsored doesn't necessarily mean it's false. It means someone paid money for it to appear. Companies pay so that readers will see their stories, buy their products, and like what the company stands for.

    As a reader, you have a right to know who's behind the information you're consuming. So, look for the phrase sponsored content. (And look carefully. Sometimes, it will be written in tiny letters.) The Internet is a vast sea of information. To use it well, we not only have to know how to swim but also how to avoid the sharks.