Travelling around the world with children is difficult enough, while attempting it without using motorized transport is even more of challenge．Even so, Dario Schworer a 42-year-old climatologist and mountain guide, and his 33-year-old wife Sabine are on a journey to do just that．

    The Swiss couple want to travel across the world's oceans and climb the highest mountain on every continent to promote Earth-friendly ways of life．

    "We are collecting good examples of dealing with climate change and living in harmony with nature and we want to spread such ideas．" Schworer said．"We want to help people affected by global warming and to inspire children for the future．"

    Recently after having spent three months teaching children in the Everest region, the couple want to show it is possible to travel through the world's climate zones using just human-power and forces of nature．

    In the 47 countries they have visited they have collected 22 tons of trash, taught people in Ecuador how the sun's rays can be used to clean water and inspired a person in Chile to build a house on water with recycled plastic bottles as a foundation．They have also collected trash in the mountains of Nepal with school children．

    So far they have communicated with 45,000 children from South America, Australia and Asia, giving presentations about the importance of recycling and using alternative energy like solar and wind power．

    When they began their adventure in 2003 they had no children of their own．But since then two has become five: daughter Sabine is now five years old, Andri was born in Chile and baby Neo was born in Australia．

    Initially the couple thought they would complete their travels in four years, but now, they believe it could take seven more．

    "Since our belief is the need to respect nature, we travel only when conditions are good," Schworer said．

    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.

    In 1996 John Jones made an unusual discovery. He had just enlarged (扩大) a piece of paper money for a friend—a Confederate bank note, money issued (发行) by banks in Southern States of America during the Civil War. When he was face to face with the picture, he couldn't believe his eyes: slaves (奴隶) happily picking cotton in their master's fields.

    Jones grew up in South Carolina. He had heard painful stories of slavery from his greatgrandmother. The picture on the money did not match (匹配) the history of African American slaves that he'd heard all his life. “I had never seen that type of picture on money before,” he said.

    Jones wondered why slaves looked so happy. He started doing research.

    Searching for and finding the answers to his questions changed his life. During two years' search, Jones found more than 120 different bills. He discovered that the bills had several things in common. They showed slaves working in jobs related to farming. Many of them showed healthy and smiling slaves at work. None of the bills showed the hardships of slavery.

    Jones wanted to share what he had learned. “I wanted other people to see what I had seen,” he said. He decided to make large paintings of the pictures on the money. After three years of work, Jones had painted more than 80 slavery scenes (场景).He paired each painting with the money on which the picture appeared. “The Color of Money”—an exhibit (展览) of his work—has toured the country.

    Jones' paintings tell an important story about the South 150 years ago. He likes to repeat the saying. “The story is on the money.” In this case, the saying happens to be true.

    Metro Pocket Guide

    Metrorail(地铁)

    Each passenger needs a farecard(车票) to enter and go out.Up to two children under age five may travel free with a paying customer.

    Farecard machines are in every station.Bring small bills because there are no change machines in the stations and farecard machines only provide up to $5 in change.

    Get one day of unlimited Metrorail rides with a One Day Pass. Buy it from a farecard machine in Metro stations. Use it after 9：30 a.m. until closing on weekdays, and all day on weekends and holidays.

    Hours of service

    Open：5 a.m. Monday-Friday, 7 a.m.Saturday-Sunday.

    Close：midnight Sunday-Thursday, 3 a.m. Friday-Saturday.

    Last train times vary. To avoid (避免) missing the last train, please check the last train times posted in stations.

    Metrobus

    When paying with exact change，the fare is $1.35. When paying with a SmarTrip card the fare is $1.25

    Fares for senior/disabled customers

    Senior citizens 65 and older and disabled customers may ride for half the regular fare.On Metrorail and Metrobus，use a senior/disabled farecard or SmarTrip^® card.For more information about buying senior/disabled farecards，SmarTrip^® cards and passes，please visit MetroOpensDoors.com or call 202­637­7000 and 202­637­8000.

Senior citizens and disabled customers can get free guide on how to use proper Metrobus and Metrorail services by calling 202­962­1100.

    Travel tips

    Avoid riding during weekday rush periods—before 9：30 a.m.and between 4 and 6 p.m.

    If you lose something on a bus or train or in a station，please call Lost & Found （失物招领）at 202­962­1195.

    TED is a non-profit organization devoted to Ideas Worth Spreading. It started out (in 1984) as a conference bringing together people from three worlds: Technology, Entertainment, and Design. Since then it has stepped into more and more fields. It includes two annual ( 年度的) conferences-the TED Conference on the North American West Coast each spring, and the TED Global Conference in Edinburgh UK each summer, which bring together the world's most excellent thinkers and doers, who are challenged to give the talk of their lives ( in 18 minutes or less).

    On ted.com, we make the best talks and performances from TED and partners available to the world, for free. More than 1, 200 TED talks are now available,' with more added each week, which cover almost all topics from science to business to global issues- in more than 110 languages. They really help share ideas in communities around the world.

    We believe in the power of ideas to change attitudes, lives and eventually, the world. So we' re building here a clearinghouse (信息交流中心 ) that offers free knowledge and inspiration from the world's most inspired thinkers, and also a community of curious souls to engage with ideas and each other. Have an idea? We want to hear from you.

    Today, TED is best thought of as a global community. It's a community welcoming people from every field and culture who seek a deeper understanding of the world.

    Want to follow TED? Here are the ways to connect:

    Get TED news and conference coverage ( 新闻报道) on the TED Blog.

    Follow TED on Twitter:

    @TED News for all TED news and information

    @TED Talks for daily TED Talk release only

    See photos from TED events on Flicker.

    Fish have different personalities which change as they experience life's highs and lows, according to British biologists.

    Researchers identified different "personalities" in their fish by observing the boldness(大胆) or shyness of individuals, according to The Nature. Like people, some fish are very confident in the face of novelty or conflict, while others are silent and fearful.

    The scientists selected particularly bold and shy rainbow trout(虹鳟鱼), and tested whether they changed their outlook depending on what life threw at them. They arranged some fish to fight and others to watch to see how both the participants and observers responded to victories and defeats. Winning or losing a fight, or even watching fellow fish overcome the difficulties influenced the future behavior of the creatures studied in the lab.

    The researchers made fish compete with much larger or smaller opponents(对手), to ensure that they would win or lose their fights. These bold fish that won their fights tended to be even bolder when later presented with a novel food item; losing their fight caused them to be much more cautious.

    Fish also learn by watching others. Bold fish watching a shy fish exploring a mystery object were much more nervous when later given a novel item for themselves.

    Predictably, shy fish that won a fight also gained more confidence, but surprisingly, shy fish that lost their fights also grew bolder when exploring strange new food, Sneddon said, adding that this could be due to what she calls a "desperado effect"(亡命徒效应).

    The new research suggests that animals can gradually adapt(使适应) their personalities. The results agree with the effects that life experience can have on humans.