Ireland，Japan，Chinascientists share the 2015 Nobel Prize for medicine．WilliamCampbell，Satoshi Omuraand Tu Youyou jointly won the prize for their work against diseases，theaward-giving body said on Monday．

Tu Youyou, a scientist at the China Academy of Chinese MedicalSciences, has no postgraduate degree. She has never studied or done researchabroad. She is neither a member of the Chi­nese Academy of Sciences nor theChinese Academy of Engineering. However, the 81-year-old phar­macologist hasbecome the first scientist on the Chinese mainland to win a Lasker Award, themedical prize of the Albert and Mary Lasker Foundation.

The Lasker Awards have existed since 1945. Tu was presented the2011 Lasker Clinical Medical Research Award on September 23. She discovered adrug called artemisinin . The drug is now widely used against malaria .

Tu and her colleagues joined a government project to find a newmalaria drug in the late 1960s during the "cultural revolution"(1966-76).  They made 380 herbal extractsfrom 200 potential recipes. The recipes came from traditional Chinese medicalbooks. The team then tested them on malaria-infected mice.  Finally Tu became interested in an extract ofthe plant qinghao, or sweet wormwood .

According to an ancient Chinese medicine book, qinghao was onceused to treat malaria. However, the extract they made in the lab didn't workwell. Maybe, thought Tu, the effective ingredient in qinghao was destroyed byhigh temperatures. Therefore, Tu tried to make the extract with an ether whichhas a much lower boiling point than water.

In 1971, after more than 190 failures, Tu finally got an extractthat was 100 percent effective against the malaria para­sites .The extract wascalled qinghaosu, later renamed artemisinin.

According to a statement on the Lasker Foundation website,during the past four decades, Tu's drug has saved millions of lives. It isespecially important for children in the poorest and least developed parts ofthe world. However, not many people knew of the scientist until she won theLasker Award this month.

Lasker Awards are known as "America's Nobels" for thereason that in the last two decades, 28 Lasker Prize winners have gone on toreceive the Nobel Prize, and 80 since 1945, according to Xinhua News Agency.

" The discovery of artemisinin is a gift to mankind fromtraditional Chinese medicine," Tu said when she received the a-ward."Continuous exploration and development of traditional medicine will,without doubt, bring more medicines to the world.

    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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    Now many young people are traveling around the world on their own，not because they have no one to travel with，but because they prefer to go alone.

Kristina Wegscheider from California first traveled alone when she was at college and believes that it is something everyone should do at least once in their life. “It opens up your mind to new things and pushes you out of your comfort zone.” Wegscheider has visited 46 countries covering all seven continents.

    In foreign countries，with no one to help you read a map，look after you if you get ill，or lend you money if your wallet is stolen，it is challenging. This is what drives young people to travel alone. It is seen as character building and a chance to prove that they can make it on their own.

    Chris Richardson decided to leave his sales job in Australia to go traveling last year. He set up a website，The Aussie Nomad，to document his adventures. He says he wished he had traveled alone earlier. “The people you meet，the places you visit，or the things you do，everything is up to you and it forces you to grow as a person，” said the 30-year-old man.

    Richardson describes traveling alone like "a shot in the arm"，which "makes you a more confident person that is ready to deal with anything". He said，"The feeling of having overcome something on my own is a major part of what drives me each day when I'm dealing with a difficult task. I walk around with my head up because I know deep down inside that nothing is impossible if you try.”

    The great 19th century explorer John Muir once said，"Only by going alone in silence can one truly get into the heart of the wilderness."

    Like people, plants experience stress. And also, like people, the response to that stress can determine success.

    Bad environmental conditions, such as drought, flood, heat and other stresses, affect yields (产量) more than crop pests and diseases. We are trying to find a way to equip plants with the ability to tolerate environmental stress and maintain high yields, said Stephen Howell, a professor of genetics and cell biology.

    Plant cells produce proteins (蛋白质) and ship them to different parts of the cell. Under normal conditions, these proteins are folded into their normal, healthy structures as they are produced. When a plant is under stress, its cells produce poorly folded or unfolded proteins. Then a built-in system senses this and “sets off an alarm in the cell,” said Howell.

    In response to the alarm, another protein (IRE1) starts working and creates a different process which activates (激活) the stress response genes whose products bring about defensive measures that help the plant survive.

    “As it turns out, responses that are activated under stress conditions actually inhibit the growth of plants,” said Howell. “This allows them to preserve their energy to survive the stress conditions.”

    For plants in the wild, this response is a help for survival, he said. In production of agriculture crops, however, this response reduces yields.

    “You don't want crop plants to stop growing,” Howell said. “You want them to continue to grow and produce even though they are under stress.”

    With the new understanding of this stress response, the next step may be to silence the alarm system, said Howell. “What may be important is to disable some of these stress responses. That may make the plant more productive under stress conditions.”

    Copenhagen Destination Guide

    The modern city of Copenhagen combines the best of European cafe culture and Scandinavian architecture. It's charming and compact with lots of local history to dive into. Although spending time in Copenhagen can become expensive, there are many ways to experience the city on a budget as well.

    Attractions

    Copenhagen is one of the world's best cycling cities. To see the city with ease, rent a bike or take a small group tour to see the sights, including the Little Mermaid, the island of Amager and the community of Christiania. You can also take a canal boat tour to see the city from a unique view. The Tivoli Gardens offer a sense of love in the evenings. There are some excellent museums to explore. Be sure to add the Museum of Art and Design to your travel plan.

    Transportation

    Kastrup Airport is the first destination for most visitors. It typically takes less than 15 minutes to get from the airport to the city center by train, so all the visitors prefer this way to travel between the two places. Canal boat tours are the easiest way to see the city's attractions. Cycling is the fastest and most flexible way to get around, and it's a refreshingly pedestrian-friendly city as well.

    Tips

    Find local sandwich shops to eat like the locals do and give your wallet a break.

    Museum lovers should have a Copenhagen Card, which provides free entrance to about 60 museums and many other attractions too.

    Consider visiting Copenhagen in the autumn, when it's a little cold but accommodations become much cheaper than those in the summer.

    Check at www.Save70.com to view price comparisons for flights and hotels before you book.

Young Americans Are Less Wealthy Than Their Parents

    The cost of living in the United States is going up, notes writer Alissa Quartz. As is reported in New York Post, Quartz points to "the costs of housing, education and health care in particular." At the same time, a new study, the report of which is called "The Fading American Dream" found that half of Americans born in the 1980s are falling behind their parents economically.

    These findings show that many younger adults are experiencing "downward mobility." In other words, they are not doing as well economically as their parents were at the same age. The idea of downward mobility is especially troubling for Americans, writes Robert Samuelson in The Washington Post. He says most U.S. citizens believe that, over time, the amount of money they earn will rise and life will get easier.

    Alissa Quartz wrote a book about the financial difficulties of Americans. In the book, Quartz tells about teachers who are struggling to pay for regular costs. One high school teacher drives for ride sharing service Uber at night to earn more money. He corrects students' papers between riders.

    A college professor turned to government assistance to feed her child and pay for a doctor. Quartz says even lawyers increasingly cannot earn an income that enables them to meet their needs. The problem of decreasing incomes in their field is made worse by debt they may have from law school. Quartz and the economists who studied these issues say many things have led to lower incomes and downward mobility. The economic recession(衰退) of 2007 to 2009 is partly to blame, they say. Modern technology also plays a part. Quartz says robots threaten to reduce the earnings of health care workers, reporters, and people who work at supermarkets, drug stores and tax preparation services. In The Washington Post, Robert Samuelson noted that poor schools, a weak housing industry and too many government rules are also to blame.

    With all these things, and more, partly responsible, what is the solution? These experts say the answer is complex. But all point to one issue that needs to be examined: economic inequality. Quartz writes that while America is one of the richest countries in the world, it also has one of the biggest divides between the wealthy and the poor.

    The researchers in "The Fading American Dream" study make a similar observation. They say raising GDP will not significantly improve the economic situation of most Americans. A higher GDP may help only those who are already doing well. Instead, the economists say, the United States could try to repeat something Americans born in the 1940s experienced. As those children grew up, they almost all benefited from a better economy.