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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    There is much to see Australia that you can't see easily in its natural setting anywhere else. A visit to Australia would not be complete without taking the chance to see some of these animals in their natural environment.

Bandicoot

    There are several species of Bandicoot around Australia, and although occasionally they can be seen during the day, they are generally nocturnal. Bandicoots are small creatures only about the size of a rat and eat small insects and plants. Several of the Bandicoots around Australia include the Eastern Barred Bandicoot, which is now rare around Australia and the Southern Brown Bandicoot found in eastern and western parts of Australia.

Koala

    Koalas are small bears like creatures that live along the east coast of Australia, with their habitat amongst the famous Eucalyptus trees. However, koalas only like to eat a small percentage of the Eucalyptus trees found around Australia. Koalas have hard black noses, with sharp claws and a thick furry coat and can grow to a weight of about 10kg, most of their time is spent asleep in the trees, which is the best place to see a koala.

Dingo

    Dingoes are found in various areas across Australia, and unlike domestic dogs do not bark. Instead, the Dingo makes a howling sound that is very particular. Dingoes generally eat mice, rabbits and rats, although sometimes they can also attack livestock(家畜) when hungry.

Frilled Lizard

    The Frilled Lizard is found in the eastern and northern parts of Australia, living within the bush. The Frilled Lizard frill normally hangs around its neck, and is made out of a flap of skin. When threatened, the Frilled Lizard will raise its frill making it seen more dangerous.

    A 12 -year-old girl who had a feeling that she might be quite clever has taken a test and proved she was absolutely right.

    After raising the idea with her parents and pestering (纠缠)them for the best part of a year, Lydia took the test in her summer holidays. It turns out the test wasn't that hard after all.

    "I was really nervous before the test and I thought it was going to be really hard. But as I started the test, I thought it was a bit easier than I thought it was going to be," she said.

    Lydia Sebastian achieved the top score of 162 on Mensa's Cattell III B paper, showing she has a higher IQ than well-known geniuses Albert Einstein and Stephen Hawking. The comparison doesn't sit well with the British student, who's currently in Year 8 at a selective girl's grammar school in Essex, England.

    "I don't think I can be compared to such great intellectuals as Albert Einstein and Stephen Hawking. They've achieved so much. I don't think it's right," Lydia told CNN.

To explain Lydia's mark's level, the top adult score in the Cattell III B test, which mainly tests verbal(语言) reasoning, is 161. A top 2% score—which allows entry to Mensa, the club for those with high IQs—would be 148 or over. Lydia scored 162, placing her in the top 1% of the population.

    Lydia's not quite sure what she wants to do when she leaves school, although she's leaning toward something "based around Maths, because it's one of my favorite subjects." "All I'm going to do is work as hard as I can, and see where that gets me," she said.

    The final results of Best-Ever Teen Fiction vote are in. While it's no surprise to see Harry Potter and The Hunger Games series on top, this year's list also highlights some writers we weren't as familiar with. For example, John Green, author of The Fault in Our Stars, appears five times in the top 100.

    Summer, like youth, passes quickly. But the books we read when we're young can stay with us for a lifetime. The following are the top 4 on the list. Enjoy.

    ⒈Harry Potter series

    The Harry Potter books make up the popular series written by J. K. Rowing. The series includes seven books. The books concern a wizard (魔法师) called Harry Potter and his journey through Hogwarts School of Witchcraft and Wizardry. The stories tell of him over coming dangerous obstacles to defeat the dark wizard Lord Voldemort who killed his parents when Harry was 15 months old.

    ⒉The Hunger Games series

    In the ruins of a future North America, a young girl is picked to leave her poor district and travel to Capitol for a battle to the death in the cruel Hunger Games. But for Katniss Everdeen, the main character in this series by Suzanne Collins, winning the Games only puts her deeper in danger as the strict social order of Panem begins to unravel (瓦解).

    ⒊To Kill a Mockingbird

    Author Harper Lee explores racial tensions in the fictional “tired old town” of Maycomb, Ala., through the eyes of 6-year-old Scout Finch. As her lawyer father, Atticus, defends a black man accused of a crime, Scout and her friends learn about the unjust treatment of African-Americans – and their mysterious neighbor, Boo Radley.

    ⒋The fault in Our Stars

    Hazel Grace, a teenage girl, has got all sorts of cancer inside her body, and her lungs aren't working very well. She knows she is dying and doesn't live in hope any more. When a man named Augustus Waters suddenly appears at the Cancer Kid Support Group, Hazel's story is about to be completely rewritten.

    Chester City Library offers a range of Library Special Needs services to people who don't have access to our library service in the usual way. As long as you live in Chester City, we'll provide a wide range of library services and resources including:

    Large printed and ordinary printed books            Talking books on tape and CD

    DVDs and music CDs          Magazines         Reference and information requests

    Home delivery service

Let us know what you like to read and we will choose the resources for you. Our staff will deliver the resources to your home for free. We also provide a service where we can choose the resources for you or someone instead of you choose the things from the library. You can also choose the resources you need personally.

    Talking books and captioned videos

    The library can provide talking books for people who are unable to use printed books because of eye diseases. You don't have to miss out on reading any more when you can borrow talking books from the library. If you have limited hearing which prevents you from enjoying movies, we can provide captioned videos for you at no charge.

    Languages besides English

    We can provide books in a range of languages besides English. If possible, we will request these items from the State library of NSW, Australia.

    How to join

   Contact the library Special Needs Coordinator to register or discuss if you are suitable for any of the services we provide—Tuesday, Wednesday and Thursday 9 am—5 pm on 4297 2522 for more information.

    Ever walked to the shops only to find, once there, you've completely forgotten what you went for? Or struggled to remember the name of an old friend? For years we've accepted that a forgetful brain is as much a part of aging as wrinkles and gray hair. But now a new book suggests that we've got it all wrong.

    According to The Secret Life of the Grown-up Brain, by science writer Barbara Strauch, when it comes to the important things, our brains actually get better with age. In fact, she argues that some studies have found that our brain hits its peak between our 40s and 60s — much later than previously thought.

    Furthermore, rather than losing many brain cells as we age, we keep them, and even produce new ones well into middle age. For years it's been assumed that brain, much like the body, declines with age. But the longest, largest study into what happens to people as they age suggests otherwise.

    This continuing research has followed 6,000 people since 1956, testing them every seven years. It has found that on average, participants performed better on cognitive (认知的) tests in their 40s and 50s than they had done in their 20s. Specifically, older people did better on tests of vocabulary, verbal memory (how many words you can remember) and problem solving. Where they performed less well was number ability and perceptual speed — how fast you can push a button when ordered. However, with more complex tasks such as problem-solving and language, we are at our best at middle age and beyond. In short, researchers are now coming up with scientific proof that we do get wiser with age.

    Neuroscientists are also finding that we are happier with aging. A recent US study found older people were much better at controlling and balancing their emotions. It is thought that when we're younger we need to focus more on the negative aspects of life in order to learn about the possible dangers in the world, but as we get older we've learned our lessons and are aware that we have less time left in life: therefore, it becomes more important for us to be happy.