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A warm drink of milkbefore bed has long been the best choice for those wanting a good night'ssleep. But now a study has found it really does help people nod off—if it ismilked from a cow at night.

  Researchers have discovered that“night milk” contains more melatonin(褪黑激素), which has been proven tohelp people feel sleepy and reduce anxiety.

  The study, by researchersfrom Seoul, South Korea, involved mice being fed with dried milk powder madefrom cows milked both during the day and at night.

  Those given night milk, whichcontained 10 times the amount of melatonin, were less active and less anxiousthan those fed with the milk collected during daytime, according to the studypublished in The Journal of MedicinalFood.

   Night milk quickened the startof sleep and caused the mice to sleep longer.

   While the effect of cowsmilk harvested at different time has not been tested on humans up to now,taking melatonin drugs has been suggested to those who are struggling to fallasleep at night.

   Previous studies have alsoindicated that milk can be excellent for helping sleep because of the calciumcontent, which helps people to relax.

  Milk is also sugar-free andadditive-free with nutritionists recommending skimmed milk as the best choicebefore bed as it is the least fattening. The more fat you take in beforebedtime, the greater burden you will put on your body at night.

    In the mid-nineteenth century, as iceboxes became increasingly common in American homes, there were efforts to find cheaper and more reliable sources of ice. In the eighteen-thirties, scientists discovered a way to make ice, which is similar to how a refrigerator works. In 1860, there were four artificial-ice plants in the United States; in 1889, there were about two hundred; by 1909, there were two thousand. Ice now came from factories, not ponds, and it was turned out in three-hundred-pound blocks by lowering steel cans of pure water into tanks of refrigerated salted water. Kept below thirty-two degrees, the salted water did not freeze, but the water in the cans did. Those cans were then lifted from the tank, and the ice was taken out of them.

    The ice blocks were delivered to home users, and to the fishing and chemical industries. On the railroads, trains carrying fruit and vegetables had cars at each end filled with blocks of ice. It was a growing industry.

    The great trade began to fall away in the middle years of the twentieth century. The railroad business shrank, and, in the immediate postwar period, block ice lost out to home refrigerators and then to small commercial ice machines. By the nineteen-sixties, things looked very dark. “It was scary,” Dan Ditmar, an ice expert in San Antonito, told me. “Your biggest customers were cafeterias and country clubs, and you'd go out there and they'd say, 'We don't need you anymore; we've got ice machines.'”

    Then the companies that survived the slump（a slump is a period when there is a reduction in business）began investing（投资）in newly developed ice-cube machines, and by the late sixties American ice was becoming a packaged-ice business. And packaged ice was exactly what the country needed. These were years of increased leisure time—more barbecues, more cars, and more houses by the lake. “Things exploded in the nineteen-seventies, Paul Handler said. Ice cubes evolved. They became hugely popular^ shoveled（铲）here and there into picnic coolers and fast-foof sodas. They became noisier.

    A so-called “smart drug” intended to improve people's cognitive (认知的) function to protect the brain from altitude sickness.

    Visiting high-altitude sites for work, spot, religious pilgrimages and military can result in cognitive effects, including memory loss and attention difficulties. There's little you can do to prevent these symptoms except acclimatize -but this takes time and doesn't always work. A drug called oxiracetam might be the answer.

    ShengLi Hu at the Third Military Medical University, Chongqing, China and her colleagues studied the performance of male military personnel at altitude. All lived in towns around 1,800 meters above sea level, During the study, they spent eight days at this altitude and then climbed for three days to reach 4,000 meters, where they stayed for up to a month.

    Twenty participants took oxriacetam three times a day for the first 15 days of the study, while another 20 received no intervention. The man did tests of attention and memory at the start and end of the study and 20 days in, by which time they had been at 4,000 meters for nine days.

    While all the participants experienced a drop in cognitive ability at 4,00 meters, those who took oxiracetam showed a much smaller drop than the control group.

    The team found that at high altitude the brain stem, which plays a critical role in supporting basic living functions, received blood at the expense of areas responsible for more advanced cognitive functions. But in people who took oxiracetam, blood flowing throughout the brain rose, thus offering more oxygen to these areas. This may be how the drug seems to lessen cognitive problems like with low oxygen.

    It isn't yet known whether diverting blood in this way could have negative effects in the long run. "The results are striking and imply that oxiracetam may be beneficial for helping to relieve cognitive ability decline caused by altitude." says Timothy Hales at the University of Dundee, UK.

    Many people go to school for an education. They learn languages, history, geography, physics, chemistry and mathematics. Others go to school to learn a skill so that they can make a living. School education is very important and useful. Yet no one can learn everything from school. A teacher, no matter how much he knows, cannot teach his students everything they want to know. The teacher's job is to show his students how to learn. He teaches them how to read and how to think. So, much more is to be learned outside school by the students themselves.

    It is always more important to know how to study by oneself than to memorize some facts or a formula （公式）. It is usually quite easy to learn a certain fact in history or a formula in mathematics. But it is very difficult to use a formula in working out a maths problem. Great scientists, such as Einstein, Newton and Galileo didn't get everything from school. But they were all so successful. They invented so many things for mankind.

Above all, they knew how to use their brains.

    This past summer I went on a journey to Canada's Arctic with Students On Ice. When I left Calgary I wondered what I would find what I would learn and who I would meet. On the trip to Ottawa I was wrapped in a blanket of uncertainty and excitement. But when I first met the group of students, scientists and leaders, I knew that l didn't have anything to worry about. The group was amazingly receptive and I was soon part of a big family setting out on an amazing adventure—an adventure of a lifetime!

    When we reached the Arctic I saw a vast Land that appeared untouched and original. I was surprised by its great size and beauty and my senses were repeatedly shocked and amazed. I stood on the Kapitan Khlebnikov and saw twelve polar bears. They walked in search of seal holes, and patiently waited for a meal. I learned that polar bears are successful only one out of every twenty hunting attempts.

    However, I learned that the Arctic and its people are being threatened by pollution and global warming. I learned that pollutants are carried by ocean and air and have a bad effect on all Arctic people. I learned that global warming has put polar bears at risk because a warmer climate means that they have a shorter time to hunt seals on the ice.

    The trip was a feast (盛宴) for the senses. I have learned more about our environment, and particularly how alive and interesting the Arctic is and why it is so important to take care of it. I learned pollution, ignorance of individual and global problems need to be solved. The Arctic deserves to be preserved. My trip with Students On Ice has made me more determined to try to ensure that I do not leave harmful footprints on either Earth or its people.

Lanrick Jr. Bennett holds a unique title in Toronto: bicycle mayor. He led a Halloween Kidical Mass ride recently, which I attended with my daughter, son-in-law, their two dogs, and my granddaughter. He is working towards making cycling mainstream and safe for all residents in the city. I did not know that Toronto had a bicycle mayor; I surely would have voted for him in an election.

The bicycle mayor program is run by BYCS, an Amsterdam-based global NGO that believes "bicycles transform cities and cities transform the world". Standing in the strange but wonderful Bentway, a park built under an elevated expressway, Bennett says, "BYCS has 150 bicycle mayors across the world. And through a few friends putting in some really nice letters of encouragement, BYCS offered me a two-year term as an advocate here in the city of Toronto, becoming the first bicycle mayor of the city."

Bennett says he is boosting the work being done to make cycling more mainstream in Toronto. "I am giving a bit more exposure to the great work that has allowed me to be able to ride a bike throughout the city. It's getting better, we're seeing more infrastructure（基础设施）, and we're seeing more people not wanting to depend on cars as their primary piece. I'm happy that I have been part of a fantastic group thus far," says Bennett.

Since there's still a lot of work to do, Lanrick Jr. Bennett has been working hard to improve cycling conditions in Toronto, and his efforts have been recognized by the community. He has been advocating for more bike lanes（车道）, better lighting, and other safety measures to make cycling a practical option for commuters（通勤者）. It's great to see people like Lanrick

Jr. Bennett working towards making cycling safe and accessible for all residents.