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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    Lockers(储物柜)have been the symbol of American high school for decades. But walk down any hallway of the new Germantown High School in Madison County, Mississippi, and you won't spot a single locker.

    New technology such as e-books, interactive(互动的)assignments and Web-based learning is making lockers in

    American high school a thing of the past.

    Officials from schools that have listed several benefits: less noise, less delay and an increased sense of safety.

    “It's all to create an environment that's student-friendly”, said Ronnie McGehee, chief official of the Madison County School District.

    Getting rid of lockers can also cut hundreds of thousands in construction costs. Madison County saved $200,000 by not including lockers in the new high school, McGehee said.

    It is also believed that removing lockers could help prevent school violence. ”Lockers give kids a place to hide things”, said Mike Nelson, founder of a safety- training group. Nelson believes that some school shootings and other incidents could have been prevented if there had been no lockers.

    However, Andrew Booth, a 10th-grader at Gemantown High, said there are some disadvantages of not having a locker. “It can make your book bag really heavy”, he said. The 16-year-old has four textbooks “plus notebooks and a binder(活页夹)” to carry to school each day.

    He said some teachers have shelves at the back of the classroom on which students can leave their bags. Others provide an extra set of textbooks in the classroom, so students don't have to carry books from home.

    New York architect Peter Lippman said schools will have to address such concerns and find ways to give students a “sense of space” “If you are carrying books around, it does limit your flexibility in the classrooms,” he said.

Lippman said he would like to see schools starting to use the new free space to provide less structured learning opportunities for students, including gathering areas and learning centers. “If you think about a school with just rows of lockers-there's nowhere for learning opportunities in that”, he said.

    The world we live in gets more mechanized every year. Some countries which were mainly agricultural a hundred years ago have now become industrial. New factories and towns have been built on good agricultural land. There are now fewer farms to serve a much greater population, so these farms must be more efficient in order to produce as much food as possible. There is no place in the modern agricultural world for the inefficient farmer. Unfortunately, many of the picturesque aspects of farming are disappearing in the search for efficiency. The more tractors are used, the fewer horses are needed. Everyone agrees that horses are far more pleasant to look at than tractors. But they are less efficient. Cows are usually milked by machinery nowadays, and even pigs are fed automatically. There is not much art or poetry on the modern farm, and the old traditional idea of a farm as a slow, peaceful, romantic place is totally wrong nowadays.

    The modern farmer has to be a mechanic, a scientist, an accountant and a gambler. The more mechanized farming becomes, the more expert the farmer has to be. He must understand what machinery is necessary for his kind of farm, and he must know how to use it efficiently. He must also understand the new technical advances in agriculture, and how to use chemical and synthetic products to improve his crops. The more workers a farmer employs, the more he must know about the problems of wages and taxes. As in any other industry, most modern farmers find it necessary to employ office staff to deal with these. But although he has more modern equipments and far more scientific aids than his grandfather had, the farmer is still dependent upon the weather. As he can never be sure what the weather will do, he must be prepared to take risks, and face the possibility of losing everything.

Many people influenced various aspects of my life, based on their personal characteristics, accomplishments, and values. I have been fortunate to have had numerous teachers and professors who I respect for their patience and intelligence. There are artists that have inspired me by their natural talents and original creativity. I value many political leaders, who have inspired me by their contributions to society, and their ability to change our futures. But of all the people I have known in my life, the person I admire most is my father.

As the youngest girl in my family, I always considered myself to be "Daddy's little girl". While I grew up, it always made me sad to see so many of my friends and neighbors without a father or father-like figure around. This helped me appreciate how my father always takes an interest in his children's lives. In every aspect of my life my father continuously pushes me to excel, so I could accomplish my work outstandingly among my people. Whenever I feel like giving up, or have a question or a concern, I know I can always call on him for advice. From him I have also learned that sometimes you have to put others' needs ahead of your own, but you should make sure you are not taken advantage of by others. His strength seems to be unbreakable during hard times, and he is extremely determined to accomplish anything he sets his mind on, no matter how tiny it is. I highly respect him for how he stands up for what he believes in, and will never back down. He is a very reserved man, but to everybody's surprise, he has a great sense of humor, and always knows how to put a smile on the faces of his wife, his children and his friends.

Living in his love and instruction, I am very proud of my father. He also professes how proud he is of his children, and is still there to support us in whatever we are involved in.

Heads or Tails?

Careful: It's not 50-50

The phrase "coin toss" is a classic synonym for randomness. But since the 18th century, mathematicians have 1 that even fair coins tend to land on one side slightly more often than the other. Proving this tiny bias, 2 , would require hundreds of thousands of carefully recorded coin flips, making laboratory tests a logistical （后勤的，组织协调的） 3 .,

František Bartoš, currently a Ph.D. candidate studying the research methods of psychology at the University of Amsterdam, became interested in this 4 four years ago. He couldn't 5 enough volunteers to investigate it at first. But after he began his Ph.D. studies, he tried again, recruiting 47 volunteers from six countries. Multiple weekends of coin flipping later, including one 12-hour marathon 6 , the team performed 350,757 tosses, breaking the previous record of 40,000.

With one side initially upward, the flipped coin landed with the same side facing 7 as before the toss 50.8 percent of the time. The large number of throws allows 8 to conclude that the nearly 1 percent bias isn't a fluke （侥幸）. "We can be quite sure there is a bias in coin flips after this data set," Bartoš says.

The leading theory explaining the 9 advantage comes from a 2007 physics study by Stanford University statisticians, whose calculations predicted a same-side bias of 51 percent. From the moment a coin is launched into the air, its entire track — including whether it lands on heads or tails — can be calculated by the laws of 10 . The researchers determined that airborne coins don't turn around their symmetrical axis （对称轴）; 11 , they tend to move off-center, which causes them to spend a little more time high in the air with their initial "up" side on top.

For day-to-day decisions, coin tosses are as good as random because a 1 percent bias isn't 12 with just a few coin flips, says statistician Ameli, who wasn't involved in the new research. Still, the study's conclusions should eliminate any lasting doubt regarding the coin flip's slight bias. "This is great experiment-based evidence 13 the bias," she says.

It isn't difficult to prevent this bias from influencing your coin-toss matches; simply 14 the coin's starting position before flipping it should do the trick. But if your friends are 15 the tiny bias, you may as well benefit from your slight advantage. After all, 51 percent odds beat a casino's house advantage. "If you asked me to bet on a coin," Bartoš says, "why wouldn't I give myself a 1 percent bias?"