Hummingbirds(蜂鸟) are one of nature's most energetic fliers and the only birds to hover(盘旋) in the air by relying on their strength alone.

    Now scientists have found that it is the ratio(比值) of the bird's wing length to its width that makes them so efficient. The discovery is helping experts compete with 42 million years of natural selection to build helicopters that are increasingly efficient.

    David Lentink, an assistant professor at Stanford University in California, tested wings from 12 different species of hummingbirds, which he sourced from museums. He placed them on a machine used to test the aerodynamics(气力学) of the helicopter blades(桨叶). Professor Lentink's team used the same machine to test the blades from an advanced micro-helicopter used by the UK's army. They found that the micro-helicopter's blades are as efficient at hovering as the average hummingbirds.

    But while the micro-helicopter's blades kept pace with the average hummingbird wings, they could not keep up with the most efficient hummingbird's wing. The wings of Anna's hummingbird were found to be about 27 percent more efficient than the man-made micro- helicopter's blades.

    While Professor Lentink wasn't surprised at nature's superiority, he said that helicopter blades have come a long way. “The technology is at the level of an average hummingbird,” he said. “A helicopter is really the most efficient hovering device that we can build. The best hummingbirds are still better, but I think it's amazing that we're getting closer. It's not easy to match their performance, but if we build better wings with better shapes, we might match hummingbirds.”

    Professor Lentink said that we don't know how hummingbirds maintain their flight in a strong wind, how they navigate(确定方向) through branches, or how they change direction so quickly. He thinks that great steps could be made by studying wing aspect ratios-the ratio of wing length to wing width. Understanding these abilities and characteristics could be a benefit for robotics and will be the focus of future experiments.

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    Global warming threatens to hold back human progress, and make unachievable all UN targets to reduce poverty, according to some of the world's leading international and development groups.

    In a report published today, Oxfam, Greenpeace and other groups say rich governments must immediately address climate change to avoid even “unbearable levels” of worldwide poverty.

     “Food production, water supplies, public health and people's livelihoods are already being damaged and weakened,” the report says. “There is no approach possible. The world must meet its commitments to achieve poverty reduction and also deal with climate change, which are closely linked.”

    The report, which draws on UN predictions of the effects of climate change in poor countries over the next 50 years, says poor countries will experience more flooding, declining food production, more disease and the extinction of entire eco-systems on which many of the world's poorest people depend.

     “Climate change needs to be addressed now. The poor will bear the great consequence of it. The frontline experience of many of us working in international development indicates that communities are having to fight more extreme weather conditions.”

    Climate change will cause great damage to agriculture and water supplies and will increase diseases. “By 2025 the number of the world's population living in countries of significant water stress will almost double, to 6 billion people. Tropical (热带的) and sub-tropical areas will be hardest hit — those countries already suffering from food shortage”.

    Poor countries mostly do not need hi-tech solutions, but would most benefit from education, research and being shown how to farm better. The report says unchecked global warming, more than wars or political upheaval (政变), will displace millions of people and unsettle many countries.

It's long been thought that in order to succeed in life you need to think only of yourself and ignore the needs of others. New research,however,suggests the exact opposite is true and being nice to others actually makes you more likely to be successful. The scientists found that ‘givers' were more likely to share knowledge,and in turn gain more information themselves.

    Researchers divided participants into three groups based on a personality test: givers, takers and matchers. In a social dilemma task, participants were given a made-up donation which was equal to the amount of ￡ 240( $400). They were then asked to decide how much of their money they would give to a shared group pool. They were told that the money in the pool would be doubled and divided equally among all group members. Thus,it would be more beneficial to the group as a whole if everyone contributed their individual donations. However, it would be more beneficial for the individual if everyone else from the group contributed,while the individual kept his or her own money. The researchers used this strategic (策略的) information sharing task to examine how much and which pieces of information participants shared:the less important and already known information or the really important information only known by the individual.

    The results showed that givers are less self-centered and self-loving than takers. Givers shared not only more money with the group, but they also shared important information. Takers on the other hand kept both the money as well as different types of information.

    The findings suggest that it may not be enough to simply provide knowledge management tools in order to make the best of knowledge exchange in a group of people. It may be necessary for leaders and managers to keep in mind the personality styles of their employees. Specifically, they should be aware that takers may keep the important information for themselves.

    On a Friday night, a poor young artist stood at the gate of the New York railway station, playing his violin. The music was so great that many people stopped to put some money into the hat of the young man.

    The next day, the young artist came to the same place, and put his hat on the ground gracefully. Different from the day before, he took out a large piece of paper and laid it under his hat. Then he began to play the violin. It sounded more pleasant than ever.

       Soon he was surrounded with people who were attracted by the words on that paper. It said, “Last night, a gentleman named George Sang put an important thing into my hat by mistake. Please come to claim (认领) it soon.”

    After about half an hour, a middle-aged man rushed through the crowd to the violinist and said, “Yes, it's you. I knew that you were an honest man and would certainly come here.” The young violinist asked calmly, “Are you Mr George Sang?” The man nodded. The violinist asked, “Did you lose something?”“It's a lottery ticket,” said the man. The violinist took out a lottery ticket on which George Sang's name was seen. “Is it?” he asked. George nodded and took the lottery ticket and kissed it, then danced with the violinist.

    The violinist was a student at an arts college and had planned to attend advanced studies in Vienna. Later his classmate asked the violinist, “At that time you needed money to pay the tuition and you had to play the violin in the railway station every day to make money. Why didn't you keep the lottery ticket for yourself?”

    The violinist said, “Although I don't have much money, I live happily. But if I lose honesty I won't be happy forever.” Through our lives, we can gain a lot and lose so much. But being honest should always be with us.

    Imagine a relay race. During this race, an athlete holds a stick as he runs a certain distance. Then he passes the stick to the next runner. That person runs faster, and then passes the stick to a third runner. Now imagine that the runners do not pass a stick. Instead they pass shiny silk, as well as gold, fruit, and glass. Imagine that the race does not move forward in just one direction. Instead the runners go back and forth along a road. They trade goods all along this route (路线) and at each end of it. Now imagine that the runners are businessmen. They lead caravans (商队) or lines of camels that carry things to sell. They travel on the ancient Silk Road to earn their living.

    The Silk Road was a complex trade network. It passed through thousands of cities and towns. It stretched from eastern China, across central Asia and the Middle east, to the Mediterranean Sea. Businessmen traveled on the Silk Road from about 200 B.C. to about 1300 A.D. Then sea travel began to offer new routes. Some people called the Silk Road the world's longest highway. However, the Silk Road included many routes--not just one smooth path. The routes ran through mountains and across deserts. They passed through an area that now includes 18 countries. The Silk Road had many dangers. These dangers ranged from hot sun and deep snow to thieves and wars. Only expert traders could survive.

    The Silk Road got its name from its most prized goods. People used silk as money. They could pay taxes or buy goods with it. Traders carried more than just silk, though. They had gold, silver, and glass from Europe. People in the Middle East and Asia wanted these things. Businessmen also took horses from flat, grassy areas in central Asia and brought them to China and other areas. The horses changed the way people farmed and ran their armies. Indian businessmen traded salt and rare, beautiful stones. Chinese merchants traded medicine and china. They also traded paper, which quickly replaced animal skins in the west. Businessmen carried apples from central Asia to Rome. The Chinese had learned to combine different trees to create new kinds of fruit. They taught this science to others, such as the Romans. The Romans began to grow apples for food. The Silk Road led to worldwide commerce 2,000 years before the World Wide Web.

    The people along the Silk Road did not share only goods. They also shared beliefs. Monks, priests, and other faith leaders taught their religions to others. The Silk Road created pathways for knowledge, diplomacy, and religion.

    Buddy or Friendship Benches (长椅)are needed because playgrounds can be lonely places sometimes. When a school places the bench, they teach a little lesson to the kids on how it is to be used. Then when a child sits on the bench, it sends out a message to others that basically says, " Hey, I'm alone right now and would welcome the company (陪伴) of others." Kids in the playground see this and from their training, they see there is a fellow student in need. They are encouraged to come over and sit on the bench and make a new friend.

    Benches like this have been around for a while now in many schools. But in Ireland, they are trying to do something different with them. This school in Cork in the south of Ireland is the 247th to get benches from a social organization called "Buddy Bench Ireland" that doesn't just provide schools with benches, but also runs special projects with trained child psychiatrists (精神病专家).They use the bench as an opportunity to start conversations about mental health. They talk about the importance of knowing and understanding your feelings and those of others.

    Judith Ashton, a co-founder of Buddy Bench Ireland said, "The children need to understand what the bench is about, what it represents —friendship, understanding, listening to each other and the most important thing is that it's important to express feelings."

    But do children really use the bench? It's a matter of great public concern. Sinead Mcgilloway from Maynooth University carried out a study and said, " We found that 40% of the children told us that they had actually used the benches at the time of the study. And over 90% said that they would talk to a child if that child was sitting on the bench. So, there's nothing to worry about.

    Children's mental health and safety at school is increasingly a concern in many countries. In Ireland, they're hoping these benches will not only tackle problems like school violence and school bullying (校园暴力和校园欺凌), but also give students the confidence to open up about their feelings.