Are you preparing for a big test? If so, you may want to go to play some basketball in between hitting the books. Doctors are starting to find more and more information that suggests a connection between exercise and brain development. Judy Cameron, a scientist at Oregon Health and Science University, studies brain development. According to her research, it seems that exercise can make blood vessels (血管), including those in the brain, stronger and more fully developed. Dr. Cameron is sure that this allows people who exercise to think better. As she says, “While we already know that exercise is good for the heart, exercise can actually cause physical changes in the brain.”

The effects of exercise on brain development can even be seen in babies. Babies who do activities that require a lot of movement show greater brain development than babies who are less physically active. Even a little movement can show big results. Margaret Barnes, a scientist, also believes in the importance of exercise. She thinks that many learning disabilities that children have in primary school or high school can result from a lack of movement as babies. Babies need movement that encourages and excites their five senses. They need to set up a connection between motion and memory. In this way, as they get older, children will begin to connect physical activity with higher learning,” says Margaret.

    Older people can develop their brains as well. Cornell University studied a group of seniors who have a short-term memory increase of up to 40 percent after exercising just three hours a week. The exercise does not have to be very difficult, but it does have to increase the heart rate. Also, just like the motion for babies, exercise for older people should not be too simple. Learning some new skills or actions, such as with yoga or tat- chi helps to open up memory paths in the brain that may not have been used for a long time. For most people, any type of physical activity that increases the heart rate is helpful. The main aim is to increase the brain's flow of blood. And your brain can benefit from as little as two to three hours of exercise a week.

    The Maldives faces the threat of extinction from rising sea levels, but the government said on Thursday it was looking to the future with plans to build homes and a golf course that can float.

An increase in sea levels of just 18 to 59 centimeters would make the Maldives — a nation of a number of tiny coral islands in the Indian Ocean — not suitable for humans to live in by 2100, the UN's climate change experts have warned.

    President Mohamed Nasheed has declared a fight for survival, and last month he signed a deal with a Dutch company to study suggestions for a floating structure that could support a conference centre, homes and an 18-hole golf course.

    The company, Dutch Docklands, is currently building floating developments in the Netherlands and Dubai. Its website said it undertook projects that make “land from water by providing large-scale floating constructions to create similar conditions as on land”.

    The Maldives began to work on an artificial island known as the Hulhumale near the crowded capital island of Male in 1997 and more than 30,000 people have been settled there in order to ease crowdedness. The city, which has a population of 100,000, is already protected from rising sea levels by a 30-million-dollar sea wall, and the government is considering increasingly imaginative ways to fight climate change.

    Nasheed, who held the world's first underwater cabinet (内阁) meeting in October to highlight his people's serious and difficult situation, has even spoken of buying land elsewhere in the world to enable Maldivians to relocate if their homes are completely covered.

    He has also promised to turn his nation into a model for the rest of the world by becoming “carbon neutral (碳中和)” by 2020. His plan involves ending fossil fuel use and powering all vehicles and buildings from “green” sources such as burning coconut husks.

    A five-year-old dog named Kelsey has been praised as a hero for helping to save the life of her owner who slipped in the snow and broke his neck.

The man, Bob, was alone when he left his Michigan farmhouse on New Year's Eve to collect firewood. Expecting a journey of only several meters, Bob was wearing just long johns(衬裤), a shirt and slippers when he went outside, although the temperature was around-4℃.

    After the accident, he was unable to move in the snow. Fortunately, Kelsey came to his assistance.

    "I was shouting for help, but my nearest neighbor is about 400 meters away, and it was10:30 pm," Bob explained. "But my Kelsey came. By the next morning, my voice was gone and I couldn't yell for help, but Kelsey didn't stop barking."

    Kelsey's companion kept him warm by lying on top of him. She licked his face and hands to keep him awake. "Kelsey kept barking but never left my side," Bob recalled. "She kept me warm. I knew I couldn't give up and that it was my choice to stay alive."

Bob spent 20 hours in the freezing cold. When he finally lost consciousness, his dog kept barking. Finally, hearing the barking, Bob's neighbor discovered him at 6:30 pm on New Year's Day and called the emergency services at once. When Bob arrived in hospital, his body temperature was below 21℃. However, doctors were surprised to find that he didn't have any frostbite(冻疮). They believed it was because of Kelsey's determination to keep him warm. Dr. Chaim Colen, the doctor who treated Bob, said, "Animals can help and his dog really saved him... He was very fortunate.

    Bob said he was "enormously" grateful to both Dr. Colen and his Kelsey. "They saved my life. They are truly heroes!"

    Nancy Ballard, 60, went for a routine checkup that turned into something extraordinary. She had just completed her master's in botanical illustration. In fact, she was canting a painting of a plant she'd done when she arrived at her doctor's San Francisco office. “It would be great if we had artwork like that for our chemotherapy(化疗)rooms, ”the nurse said. Ballard asked to see one.

    She was shocked by what she found. The walls were bare, and the paint was chipping(剥落).She could tell where old artwork had hung because of the naked nails. It was a depressing room for a depressing routine—patients had chemo drips for perhaps several hours, often with nothing to look at other than those sad walls. She couldn't imagine how anyone could even think about getting healthy in a room like that. As it happened, Ballard's physician, Stephen Hufford was ill with cancer himself, so finding time to decorate the rooms was low on his to-do list. So Ballard made it her mission to brighten up the place.

    She wrote to 20 local interior designers and asked whether they would donate their time and money to transform just one of Dr. Hufford's rooms each. Six of them wrote back almost immediately. Each of them ultimately chose a theme: The dragonfly room, for example, now features bright artwork and dragonfly wall ornaments. Most rooms got new paint, light fixtures, artwork, and furniture. Each room cost about $5, 000.

    Dr. Hufford was delighted.“ All the patients feel soothed by it.” he noted. He even said that his own tone of voice was different in the rooms and that he was better able to connect with his patients.

    Ballard was so encouraged that she created a nonprofit to raise money and decorate more spaces. Since then, she has worked on 20 projects, including one in Pennsylvania. She once went to Philadelphia for a ribbon cutting, and a woman there was on her third battle with cancer. When she saw what Ballard had done, she said, “I'm gonna beat it this time.I thought I wasn't going to, but now I know I'm gonna beat it.”

    Shukri Noor, 12, arrived in Anchorage, Alaska, one year ago. The sixth grader and her family are refugees (难民) from Kenya. "Since I didn't speak English, it was hard to communicate with others," Shukri said. "I had no friends."

    "Anchorage receives about 130 refugees every year. Most are from Somalia. The rest come from Iraq, Sudan, Cuba, Central America, and other places. Like Shukri, many of the kids feel alone. They're dealing with a lot of adjustments (适应)," Katie Bisson says. She manages to support for newcomer students in the Anchorage School District (ASD).

    At the Newcomers' Center, the ASD offers a special program for students who are new to the US. The kids spend part of each day at the center and part of the day at their neighborhood school. At the center, the students study English and other subjects.

    The main goal is to help newcomers reach the point where they attend their neighborhood schools all day. "Until then," Bisson says, "they have the support of being with kids like them, who are facing the same challenges (挑战)."

    Anchorage has a population of 300, 000.Among the ASD's 48, 000 students, 98 languages are spoken. According to Bisson, the ASD's newcomers program helps students understand a new culture so they can "start off on the right foot".

    The Newcomers' Center gives attention to middle school and high school students. For younger kids, the ASD offers a six-week summer program, which Shukri attended. "It helped me learn the language," she says. "I played sports with kids after class, and I played math games with my classmates. I feel very comfortable now."

    The fridge is considered necessary. It has been so since the 1960s when packaged food list appeared with the label: "Store in the refrigerator."

    In my fridge less Fifties childhood, I was fed well and healthy. The milkman came every day, the grocer, the butcher, the baker, and the ice-cream man delivered two or three times each w eek. The Sunday meat would last until Wednesday and the bread and milk left became all kinds of cakes. Nothing was wasted, and w e w ere never troubled by rotten food. Thirty years on, food deliveries have stopped, and fresh vegetables are almost impossible to get in the country.

    The invention of the fridge contributed comparatively little to the art of food preservation. Many well-tried techniques already existed — natural cooling, drying, smoking, salting, sugaring, bottling...

    What refrigeration did promote was marketing — marketing hardware and electricity, marketing soft drinks, marketing dead bodies of animals around the world in search of a good price.

    Consequently, most of the world's fridges are to be found, not in the tropics where they might prove useful, but in the rich countries with mild temperatures where they are climatically almost unnecessary. Every winter, millions of fridges hum (make a low continuous sound) away continuously, and at vast expense, busily maintaining an artificially-cooled space inside an artificially-heated house —while outside, nature provides the desired temperature free of charge.

    The fridge's effect upon the environment has been clear, while its contribution to human happiness has been unimportant. If you don't believe me, try it yourself, invest in a food cupboard and turn off your fridge next winter. You may miss the hamburgers, but at least you'll get rid of that terrible hum.