A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech integrated systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.

    “It's extremely important for us to think about this as a whole system and not just the sum of a bunch of individual components (元件),” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. A few years ago, his team got the go-ahead to start piecing together the components.“The added difficulty with a project like this is that actually none of those components are off the shelf and so we have to develop them all on our own,” he said.

    They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of interdependencies on the individual components, each of which individually has to perform well, but then has to be matched well to everything it's connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.

    While this first robotic flyer is linked to a small, off-board power source, the goal is eventually to equip it with a built-in power source, so that it might someday perform data-gathering work at rescue sites, in farmers' fields or on the battlefield. “Basically it should be able to take off, land and fly around,” he said.

    Wood says the design offers a new way to study flight mechanics and control at insect-scale. Yet, the power, sensing and computation technologies on board could have much broader applications. “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”

    Many Years ago three soldiers,hungry and tired of battle,came upon a small village.The villagers,suffering a bad harvest and the many years of war,quickly hid what little they had to eat and met the three in the village square, shaking their heads and sighing,"Well,we are starving."The soldiers communicated with each other quietly and then the first soldier turned to the villagers.“Your poor fields have left you nothing to share,so we will share what little we have: the secret of making soup from stones.”

    Naturally the villagers were intrigued and soon a fire was built to the village's greatest pot,and then the soldiers dropped in three smooth stones.

    “Now this will be a fine soup,”said the second soldier,"but a handful of salt and some parsley（香芹）would make it wonderful!"Up jumped a villager,crying “What a piece of luck!I've just remembered where some has been left!”

    And off she ran,returning with parsley.As the pot was boiling,the memory of the villagers improved: soon carrots,beef and cream had found their way into the great pot.They ate and danced and sang well into the night, thrilled about the feast and their new-found friends.In the morning the three soldiers awoke,finding all the villagers standing before them.At their feet lay a bag of the village's best bread and cheese.“You have given us the greatest gift,”said an elder,“and we shall never forget.”The third soldier turned to the crowd,and said,“There is no secret,but this is certain: people working together can accomplish great things.”At last the light dawned on villagers.Off the soldiers wandered,down the road.

    The baby is just one day old and has not yet left hospital. She is quiet but alert (警觉的). Twenty centimeters from her face researchers have placed a white card with two black spots on it. She stares at it carefully. A researcher removes the card and replaces it by another, this time with the spots differently spaced. As the cards change from one to the other, her gaze(凝视) starts to lose its focus—until a third, with three black spots, is presented. Her gaze returns: she looks at it for twice as long as she did at the previous card. Can she tell that the number two is different from three, just 24 hours after coming into the world?

    Or do newborns simply prefer more to fewer? The same experiment, but with three spots shown before two, shows the same return of interest when the number of spots changes. Perhaps it is just the newness? When slightly older babies were shown cards with pictures of objects (a comb, a key, an orange and so on), changing the number of objects had an effect separate from changing the objects themselves. Could it be the pattern that two things make, as opposed to three? No again. Babies paid more attention to squares moving randomly(随意地)on a screen when their number changed from two to three, or three to two. The effect even crosses between senses. Babies who were repeatedly shown two spots became more excited when they then heard three drumbeats than when they heard just two; likewise(同样地) when the researchers started with drumbeats and moved to spots.

    Honey (蜂蜜) from the African forest is not only a kind of natural sugar, it is also delicious. Most people, and many animals, like eating it. However, the only way for them to get that honey is to find a wild bees' nest (巢) and take the honey from it. Often, these nests are high up in trees, and it is difficult to find them. In parts of Africa, though, people and animals looking for honey have a strange and unexpected helper—a little bird called a honey guide.

    The honey guide does not actually like honey, but it does like the wax (蜂蜡) in the beehives (蜂房). The little bird cannot reach this wax, which is deep inside the bees' nest. So, when it finds a suitable nest, it looks for someone to help it. The honey guide gives a loud cry that attracts the attention of both passing animals and people. Once it has their attention, it flies through the forest, waiting from time to time for the curious animal or person as it leads them to the nest. When they finally arrive at the nest, the follower reaches in to get at the delicious honey as the bird patiently waits and watches. Some of the honey, and the wax, always falls to the ground, and this is when the honey guide takes its share.

    Scientists do not know why the honey guide likes eating the wax, but it is very determined in its efforts to get it. The birds seem to be able to smell wax from a long distance away. They will quickly arrive whenever a beekeeper is taking honey from his beehives, and will even enter churches when beeswax candles are being lit.

    This is a time of year when high school students and their families are thinking hard about college. As seniors, juniors, and parents identify their top choices, discussions typically focus on the college itself. Is the institution small or large? How strong are the academics? What is the social life like? Do I like the campus? Such considerations are important, but they can cover the all­important question: Where will these college years lead?

    Applicants should think seriously about which college on their list can best prepare them for the real world. They should look for campuses that offer well­structured programs to help them form a direction for their lives and develop the capacity to take steps along that path.

    One of the most striking recent phenomena about college graduates in America has been the "boomerang" student: the young person who goes away to college, has a great experience, graduates, and then moves back home for a year or two to figure out what to do with his or her life. This pattern has left many graduates — and their families — wondering whether it makes sense to spend four or more years at college, often at great expense, and finish with no clear sense of who they are or what they want to do next.

    The trend points to one of the great shortcomings of many of our nation's leading colleges and universities. Structured opportunities to think about life after graduation are rare. The formal curriculum focuses almost universally on the academic disciplines of the arts and sciences.  Advising on how various majors connect to pathways into the workplace is typically haphazard (没有条理的). Career planning offices are often shorthanded and marginal (不重要的) to college life.

    It doesn't need to be this way, and in recent years some of the country's top colleges have enriched their academic offerings with opportunities for students to gain real­world experiences.

    For Chinese, it's a time for dragon boat racing and Zongzi (粽子). But across the Yellow Sea, South Korea, wrestling (摔跤) and swing play are the highlights. However, both events go by the same name—the Dragon Boat Festival—which falls on May5 of the lunar calendar.

    One festival, two cultures: does one nation have the right to call its own? It has been reported that South Korea will apply (申请) to the United Nations Educational, Social and Cultural Organization (UNESCO联合国教科文组织) to make the celebration its cultural heritage (文化遗产). If successful, people from other countries may see the Dragon Festival as a Korean creation.

    As the birthplace of the yearly event more than 2, 000 years ago, China is not happy with the situation. "It would be a shame if another country successfully made a traditional Chinese festival part of its own cultural heritage ahead of China," said Zhou Heping, deputy culture minister. The Ministry of Culture is even thinking of making its own application to UNESCO, covering all traditional Chinese festivals, including the Dragon Boat event.

    Over the years, the Dragon Boat Festival has spread throughout the world. In Japan and Viet Nam, as well as South Korea, the festival has mixed with and become part of local culture. With this in mind, some experts say that it is meaningless to argue about which country the festival belongs to. "No one can deny that it came from China," said Long Haiqing, an expert from Hunan Province. "But if all the countries involved can protect culture heritage together, they will all benefit."