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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    One Moore Elementary school teacher is showing students the importance of communication through “shout-outs”. Third Grade Moore Elementary teacher Lindsey Winders said a shout-out is a compliment（称赞）that students can say or write down. “Like, 'hey I noticed you doing a really great job solving your math facts yesterday. I wanted to make sure you know that I saw you do that,” Winders said.

    Winders said she makes sure she is giving shout-outs to her students every day. “I might write them a sticky note, or write them a quick little note in their plans. I might just say it to them on their way into the classroom or on their way out of the classroom, but most importantly I try to do it every day,” Winders said.

    In addition to the compliments, Winders has the students greet each other every morning during morning meeting. She will have students give examples to the class of how to communicate in different settings. Third grade student Nayelli Moranchel said she has given at least six shout outs this year. “It makes me happy, because they always write something back,” Moranchel said.

    Recently, Winders took it one step further and wrote a personalized note on each of her students' desk. “In our classroom, sometimes it can be challenging for me to give a compliment or a shout out to each and every one of them in a way that feels equal and valuable at the same time. So I thought what's a better way to be able to do that than leaving a note on their desk that can stay for as long as they want it.” Winders said.

    Winders said it is encouraging when she sees her students copy the act, and give each other compliments without her guidance.

    Babies have an astonishing talent that adults entirely lose. By the age of one, they can recognise the significant noises around them and group them into a language. When we have lost this capacity as adults, it becomes enormously difficult to distinguish between sounds that are glaringly different to a native speaker. It all sounds Greek to us. This is because the range of possible sounds that humans use to convey meaning may be as high as 2,000, but few languages use more than 100 and even then the significant noises－the phonemes (音素) of a language－each cover a range of sounds and so vague distinctions which would change the meaning of a word in other languages.

    But where do these phonemes come from and why do they shift over time? New research suggests that the apparently arbitrary distribution of some sounds around the world may be partially explained by diet. This is unexpected. We'd rather think of language as product of our thought  rather than of the arrangement of our teeth. In reality, though, any given language must be both.

    Hunter gatherer languages very seldom use the sounds known as labiodentals (唇齿音)－those such as f and v－that are made by touching the lower lip with the upper teeth. Only two of the hundreds of Australian aboriginal languages use them, for example. But in cultures that have discovered farming, these consonants (辅音) are much more common. The argument goes that farmers eat more cooked food and more dairy than hunter gatherers. Either way, they need to chew mush less, and to bite less with their front teeth. So farmers grew up with smaller lower jaws and more of an overbite than their ancestors who had to bite through harder foods. It became easier for them to make the labiodental consonants instead of purely labial (唇音) ones: one example is that f come to take the place of p. Romans said "pater" but English speakers (unless they're Rees－Moggs) say "father".

    Beyond these particular changes, the story highlights the way in which everything distinctively human is both material and spiritual: speech must combine sound and meaning, and the meaning can't exist or be transmitted without a real object. But neither can it be reduced to the purely physical, as our inability to understand or even to recognise foreign languages makes clear. The food we eat shapes our jaws, and our jaws in turn shape the sounds of our language. The ease with which we eat probably shapes our thought too, as anyone who has suffered toothache could testify. What we eat may have shaped the sounds of our language, but how we eat changes how we feel and what we use language to express. A family meal is very different from a sandwich at the office desk, even if the calorie is the same. Food has purposes and meanings far beyond keeping us alive and pleasing the Palate (味觉).

    Living and dealing with kids can be a tough job these days, but living and dealing with parents can be even tougher.

    If I have learned anything in my 16 years, it is that communication is very important, both when you disagree and when you get along. With any relationship, you need to let other person know how you are feeling. If you are not able to communicate, you drift apart. When you are mad at your parents, or anyone else, not talking to them doesn't solve anything.

    Communication begins with the concerns (关心) of another. It means that you can't just come home from school, go up to your room and ignore (不理睬) everyone. Even if you just say "Hi", and see how their day was for five minutes, it is better than nothing.

    If you looked up the word "communication" in a dictionary, it would say "the exchange of ideas, the conveyance (表达) of information, correspondence (通信), means of communication: a letter or a message". To maintain (保持) a good relationship, you must keep communication strong. Let people know how you feel, even if it's just by writing a note.

    When dealing with parents, you always have to make them feel good about how they are doing as a parent. If you are trying to make them see something as you see it, tell them that you'll listen to what they have to say, but ask them politely to listen to you. Yelling or walking away only makes the situation worse.

    This is an example: one night, Sophie went to a street party with her friends. She knew she had to be home by midnight after the fireworks, but she didn't feel she could just ask to go home. That would be rude. After all, they had been nice enough to take her along with them. Needless to say, she was late getting home. Her parents were mad at first, not when Sophie explained why she was late, they weren't as mad and let the incident go. Communication is the key factor here. If Sophie's parents had not been willing to listen, Sophie would have been in a lot of trouble.

    Communication isn't a one-way deal: it goes both ways. Just remember: if you get into a situation like Sophie's, telling the other person how you feel-listening is the key factor to communication.

    Here are some events in the following months. Have a look and pick out your favorite.

    AVCS Informational Tour

    Aliso Viejo Christian School, a highly rated private school, which serves children in grades, invites potential families to its annual AVCS informational tour. Come and see its facility, meet its staff, check out its curriculum and amazing programs. The tour would love to share the school with you and answer any questions.

    Location: AVCS Campus

    German Immigrants Exhibition

    German immigrants played a huge role in shaping Indianapolis through the 19th century. They brought educational reform, political activity and greenhouse farming. In addition to produce, these immigrants also kept their communities full of flowers and trees, know about this part of history in October.

    Location: Indiana Historical Society

    Whale Watching

    Gray whales migrate (迁徙) annually along the west coast of North America. They can be seen from the Orange County coast from December through early April. Summer and fall bring the giant blue whales. They can be seen from June through September. Since the gray whales migrate just a few miles off the coast, simple sail from Newport Beach enables you to see these spectacular creatures in their natural habitat.

    Location: Newport Beach

    Sunday Brunch(早午餐)

    Sunday brunch is a wonderful way to enjoy your weekend. At View Restaurant, Sunday brunch is always accompanied by champagne, spectacular views and unique atmosphere. The menu includes traditional breakfast foods and lunch favorites like barbeque and fresh fish selections. You can also choose to view sporting events in the restaurant. With enough variety to satisfy every appetite from kids to adults, this is one Sunday brunch you'll keep coming back to!

    Location: View Restaurant

    If your life were a book and you were the author, how would you want your story to go? That's the question that changed my life forever.

    At the age of 19, I became a massage therapist(治疗师). For the first time in my life, I felt free, independent and completely in control of my life. That is, until my life took a detour. I was diagnosed with bacterial meningitis. Over the course of two months, I lost my spleen(脾), my kidneys, and both of my legs below the knees.

    One day, I went home. I crawled into bed and this is what my life looked like for the next few months me passed out, escaping from reality, with my legs resting by my side. I was completely physically and emotionally broken. But I knew that in order to move forward, I had to let go of the old Amy and learn to embrace the new Amy. And that is when I began to realize that I didn't have to be small any more. I could be as tall as I wanted or as short as I wanted depending on whom I was dating. And if I snowboard again, my feet aren't going to get cold. And the best of all, I thought, I can make my feet the size of all the shoes that are on the sales shelf. And I did!

    I started snowboarding. Then I went back to work. And then I co-founded a non-profit organization for physical disabilities so that they could get involved in action sports. And just this past February, I won two World Cup gold medals, making me the highest-ranked adaptive female snowboarder in the world.

    Eleven years ago, when I lost my legs, I had no idea what to expect. But if you ask me today, if I would ever want to change my situation, I would have to say no, because my legs haven't disabled me. They've forced me to rely on my imagination and to believe in possibilities, and that's why I believe that our imaginations can be used as tools for breaking through borders, because in our minds, we can do anything and we can be anything. It's belief in those dreams and facing our fears directly that allow us to live our lives beyond our limits.