It has been several weeks since we tookour daughter to college and she seems to be adjusting  well after a short period of homesickness.For us, though, it's another story. Like most parents, I love checking in on mychildren at night. But now she's gone, and I find nighttimes the hardest. Imiss her most at night.

    In my neighborhood, most of the parentswhose kids are off to college are dealing with similar melancholy. Myhusband is filled with anxiety. One friend talked about getting this sickfeeling in her stomach as she prepared for the college drop-off. We complainedthat many of us were too busy to truly enjoy being with our children while wehad them.

    For us moms, seeing Toy Story 3 onlymade the sadness worse as we watched the character Andy, who is the same age asour kids, say goodbye to his childhood as he prepares to leave for college. Andit's not just “first-time” parents like me. Two moms who have kids already wellinto college said the separation didn't get any easier. “You feel likesomething has been taken away from inside you,” said one of them.

    I imagine things will get easier withtime, especially as I see my daughter adjust to college life. Meanwhile, as Ikeep my cell phone close to me in bed and text my daughter goodnight and sweetdreams every night, I like to think at messages serve as a night light thatkeeps her safe.

    If you are sitting, please stand up. Move your legs. Touch your toes if you can. Do anything but sit. New research shows that if you cut down on the time you spend sitting, you might live longer. Sitting less than three hours a day might extend your life by two years. Cutting television time to less than two hours a day can add one point four years to life.

    The human body is designed to move. The fact is just the opposite. Modern lifestyles and office jobs rarely give us the chance to move around. We sit while we're eating; we sit in the car; we sit while we are watching TV. And most of us sit for many hours at work. Sitting is something we do all the time. On average, Americans sit for four and a half to five hours a day. But that does not make sitting good for us.

    Though you may exercise often, that does not mean you can sit for the rest of your waking hours. We can't throw away physical activity. It is extremely important. Even if you exercise for 30 minutes a day, what goes on in the other 23 and a half hours a day is also very important.

    Changes are coming to some offices, especially in the design of desks. A “standing desk” lets people stand while they work. Another new design is called the “treadmill desk”. It is an exercise machine that lets you walk slowly in one place. Even some U.S. schools begin to experiment with desks that are part bicycle to keep children moving.

    Many companies may not buy a standing desk for everybody. However, they may get five standing desks or a treadmill desk for their employees and put them in a certain place where people can go for an hour a day to answer their emails or talk on the phone. Experts suggest some other activities: take a walk at lunchtime; walk to the offices and talk directly instead of emailing colleagues. All these activities may help you live longer.

    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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    The town of Green Bank, West Virginia, is the site of the largest radio telescope in the world, so Internet connections and anything else that can create electromagnetic(电磁的) waves, such as smart phones and microwave ovens, are banned.

    Green Bank is frozen in time, somewhere in the 1950s, because there's a 33,000-square-kilometer zone of silence due to the telescope. Cell phone towers are forbidden.

    The closer you get to the telescope, the greater the restrictions. There's a 16-kilometer radius(半径) around the observatory where radio-controlled items, even toys, cannot be used.

    Telescope employees even work in a special room that blocks electromagnetic waves from leaving it. “Here imagine a submarine(潜艇), water cannot get inside, and so this room is an electric submarine. No electromagnetic waves can get into this room, just as you can't go beyond it,” Michael Holstein, an observatory officer, said.

    The size of a football field, the telescope is so sensitive that it could pick up signals sent from an alien world. And scientists can't wait for that to happen.

    “All the signals that we now receive with the help of telescopes are signals that come from cosmic objects — stars, galaxies. We have not yet received anything from intelligent civilizations,” scientist Richard Lynch said.

    Local people respect the work of the scientists. “Yes, we are different. Many would say that we live the old-fashioned way, in the past. But for us, it's just the way of life that we have always lived,” Sherry said.

    “When we want to meet friends, we just call each other on a wire phone. And instead of sitting in front of your screen, we talk, we go fishing, to the mountains,” resident Sherry said.

    For the latest news, residents read the weekly local newspaper. When she's looking for a phone number, Sherry reaches for the phone book.

    And instead of Facebook, Sherry enjoys daily conversations with her customers. In this town, everyone knows each other and communication is face to face.

    What do you do when you need to look something up? Go to the library? Open an encyclopedia(百科全书)? Click onto the Internet? These days, most people go straight to Wikipedia, the online encyclopedia. But how reliable is it?

    There's no denying the popularity and usefulness of Wikipedia. It attracts as many as 78 million visitors every month, and the site is available in more than 270 different languages. It's one of the most comprehensive resources available, which includes almost all details, facts and information that may be concerned. It's got much more information than an ordinary encyclopedia. The site is updated on a daily basis by thousands of people around the world. Anyone with an Internet connection can log on and edit the contents or add a new page. And you don't need any formal training.

Of course, there are some controls. Wikipedia has a team of more than 1,500 administrators who check for false information. And main targets for harmful comments(such as politicians) are off-limits to public editing. But with more than 16 million articles to keep an eye on, it isn't easy. So, while Wikipedia benefits from being constantly updated with information from all over the world, it's also open to “vandals”（恣意破坏公共财物者）.

    Some of the damage is easy to notice. One person drew devil horns and a moustache on Microsoft chairman Bill Gate's photo, while another edited Greek philosopher Plato's biography to say he was a “Hawaiian weather man who is widely believed to have been a student of 'Barney the purple Dinosaur'.

    But other things are harder to spot. The most common form of vandalism (恣意破坏公共财物罪)involves adding tiny items of false information into the biography of a famous person. Unbelievably, some of this misinformation has appeared in newspapers, with The Daily Mail, The Guardian and The Independent all having fallen victim to the dirty tricks. For example, in an article about British comedian Sir Norman Wisdom, one newspaper claimed that he co-wrote Dame Vera Lynn's wartime hit There'll be bluebirds over the White Cliffs of Dover. He did no such thing. And in other article, it was reported that TV Theme tune composer Ronnie Hazlehurst had written the S Club 7's hit Reach again, not true. So, if you're going to use any information from Wikipedia, make sure you double-check it first.

When bicycle-sharing company oBike pulled out of Singapore abruptly last year, it left the city with unattended bicycles everywhere. Myanmar businessman Mike Than Tun Win saw the perfect opportunity to turn trash (垃圾) into treasure. "What if these bicycles could be distributed to poor students in villages so they can cycle to school? " he thought.

Mr Than, 33, grew up in Mandalay, where he used to walk to school as a student. While traveling through rural (乡村的) areas in Myanmar over the last few years he saw things had not changed. Long lines of children in rural villages continue to walk 30 minutes to an hour just to get to school. "I thought if we could just reduce the time they take, they could spend more time studying, gain more knowledge and increase their chances of getting out of poverty (贫困), " he said.

With that, he started a movement called Lesswalk with the intention of buying bicycles from bike-sharing firms oBike and ofo—which have stopped operations in Singapore — and shipping them to Yangon. He would renew the bicycles before distributing them to teenagers and families living in rural villages in Myanmar, beginning with villages in Mandalay and Sagaing areas.

Over the last three months, the businessman has bought 10, 000 bicycles in Singapore and Malaysia. He paid for 5, 000 of the bicycles out of his own pocket, with other sponsors paying for the rest.

Mr Than plans to modify (修改) the bicycles so that they can better suit the needs of the children in villages. Most of the time they ride around with their little brothers and sisters. "I'm planning to add an extra seat at the back so that they can go to school together," he said. He also plans to remove the digital locks and give each a new one that works better in villages.

Including the cost of shipping, modification and distribution, Mr Than thinks each bicycle might cost him around US $35 to US $40. "I might have to spend more money, but it is better that these bicycles are going to help some people rather than going to waste," he said.