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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    When Steve Jobs was born on February 24, 1955, in San Francisco, California, his unmarried mother decided to put him for adoption because she wanted a girl. So in the middle of the night, his mother called a lawyer named Paul Jobs and said, “We have an unexpected baby boy; do you want him?” But his mother told his future parents to promise that they would send Jobs to college. After Steve Jobs graduated from high school, he went to college but decided to drop out because it was so expensive that he had to sleep on the floor in his friends' rooms.

At 20, he and a friend started a company in a garage on April 1, 1976. Jobs named their company —-Apple in memory of a happy summer he had spent as an orchard (果园) in Oregon.

    After 10 years of hard time and failures, starting from two kids working in a garage, Apple computer eventually grew into a big company with over 4,000 employees.

    At 30, Jobs , however, was fired from the company he co-founded. But after he had to leave the company, Apple was under heavy pressure from rival (对手) Microsoft and in 1996 posted billions of dollars in losses. Apple needed Steve Jobs and he was appointed as Apple' CEO in1997. Under his leadership, Apple returned to profitability and introduced new products such as the iPhone and the iPad.

    Steve Jobs once said, “Sometimes life hits you in the head with a brick, Don't lose faith. I'm convinced that the only thing that kept me going was that I loved what I did. You've got to find what you love. If you haven't found it yet, keep looking.

    The 2012 Nobel Prize for Literature was awarded to Mo Yan for his writing that mixes folk tales, history and the modern events with hallucinatory realism（魔幻现实主义）, the Swedish Academy announced.

    The 57-year-old is the first Chinese resident to win the prize. Only one other Chinese-language writer has won the Nobel Prize for Literature. Gao Zingjian was honored in 2000. However, he is a French citizen.

    Mr Mo said he was “overjoyed and scared” when he learned he had won the award. He will receive his Nobel diploma, a medal and more than one million dollars at a ceremony in Stockholm in December.

    China is celebrating the victory of this native son. Minutes after the award was announced, millions of Chinese expressed pleasure and pride for Mo Yan on social media websites. Senior CPC leader Li Changchun has congratulated Mo Yan on winning the 2012 Nobel Literature Prize. Li says in a letter to the China Writers Association that Mo's winning of the prize reflects the prosperity and progress of the Chinese literature.

    His real name is Guan Moye. Mo Yan means “Don't Speak.” The writer said he chose the name to remember to stop his tongue from getting him in trouble. Mo Yan's novel “Red Sorghum” first became a cable hit on the big screen both at home and abroad in 1987. The film was directed by Zhang Yimou and marked the acting start of Gong Li.

    As a productive author, Mo has published dozens of short stories, with his first work published in 1981. Mo Yan's other major works include, “Big Breasts and Wide Hips,” “Republic of Wine” and “Life and Death Are Wearing Me Out.”

    One evening, author Neil's son was angry. Neil had said one of those things that parents say, like “isn't it time you were in bed.” His son looked up at him, angry and said, “I wish I didn't have a dad! I wish I had … a goldfish!” That conversation gave birth to Neil's book, “The Day I Swapped My Dad for Two Goldfish”. The book is a funny adventure of a son searching for the dad he swapped.

    Whether they realize it or not, fathers play an important role in their children's development. Roland Warren, Director of the National Fatherhood Initiative, says that, “The shape of their dads has a role in the kids' soul.” I agree. We live in the best of times and the worst of times for fatherhood. We live in the best of times because fathers who are engaged in their child's life spend more time than fathers of any previous generation. We live in the worst of times because there are still millions of children who continue to miss the regular presence of Dad.

    What difference does a dad make? Are they really that important? For the most part, studies have proved clearly that fathers, whether they live with their children or not, matter in the lives of their children. When fathers are present, they provide economic support for their children and caregiving responsibilities. Well-fathered children are shown to be more emotionally intelligent and socially successful as adults. When fathers are absent, their absence may negatively influence children's academic achievement, general behavioural adjustment and anger management, especially in males.

    Yet just being physically present isn't enough to be a great father. It is important that a dad be warm and emotionally available to his child. Author and researcher, John Gottman, describes this kind of father as an “emotion coaching father”. Emotion coaches are parents who listen to their children's feelings, see the sharing of feelings as an opportunity for intimacy（亲密）. It is not just the mere presence of fathers that matters, but how they are present. Most children long for and need a loving, devoted and responsible father.

    Whales, like all mammals(哺乳动物),need air, and come to the surface to breathe through a blowhole. A drone(无人机)that floats over the blowholes of humpback whales as they are making annual journey along Australia's east coast is being used by Australian scientists for collecting nasal mucus(鼻腔粘液)of whales.

    Vanessa Pirotta, a biologist at Macquarie University says that nasal mucus indicates the health of the whale. "It is the biological mixture that you see as a whale takes a breath as it surfaces from the water," she said. You can hear sounds of sharp breaths as a whale breathes because, after all, they are animals like you and I. So as they take a breath it is a lot of lung bacteria coming out from their lungs, which we can collect to provide a brief idea of whale health.

    Australian researchers have attached a special dish that is used in scientific tests to a drone which flies through the whale's nasal mist. As a whale comes to take a breath—you can actually see it coming to the surface on really good weather days —the drone then lowers, the dish is then opened, collecting nasal mucus for later research.

    The research could help to solve one of the secrets of another impressive creature of the deep —the Southern right whale. Its numbers have recovered on Australia's west coast since hunting became suppressed but its population on the eastern seaboard remains stubbornly low.

    In the past, studies into whale health had to rely on examining whales that were either killed or those whales that had been trapped on a beach. Drones allow scientists to collect nasal mucus from free-swimming whales to gather information in a safe way.

The Outdoor City Adventure Book Festival

    For one week in July, Sheffield Central Library becomes the center of adventure in the Outdoor City. Check out some of the events. Most of them are free but early booking is recommended.

    July 10

    Bee Quest - A Hunt for the World's Most Elusive (难以捕捉的) Bees Central library Carpenter Room, 7:00-8:30pm.

    A hunt for the world's most elusive bees leads Professor Dave Goulson from Poland to Patagonia, deep into the Ecuadorian Jungle. He also explores closer to home.

    Among secret places hidden right under our noses and through his scientific expertise (专业知识), shows us that beauty hides in the most surprising places.

    July 11

    Clarion Call: A Heartfelt Tribute to Sheffield's Access Pioneers

    Central library Carpenter Room, 10:30-11:30am.

    Well-known walker, activist and campaigner, Terry Howard takes us back a hundred years and shares the story of the role Sheffielders played in the first fights for our right to freely walk on the Peak District moors (旷野). The Clarion Ramblers is thought to be the first working class walking club. This is the story of their important role in gaining us the access we all enjoy today.

    July 12

    The Wainwrights in Color Central Library Carpenter Room, 1:30-2:30pm.

    Inspired by the work of the great Alfred Wainwright, over 10 years Andy Beck has reproduced in watercolor all 1, 500 pictures drawn in A Pictorial Guide to the Lakeland Fells. Andy speaks about how the scenes in the Lake District have changed during the last 50 years.

    July 13

    Craft (制作) Your Own Adventure Journal-A Workshop Central Library Reading Room, 2:00-3:00 pm,￡5.

    Learn paper craft techniques to make your own beautiful travel journal. Get advice from our expert tutor on using old photos adventures and holidays.

    Collecting stories and memories from your.