On Monday, the Centers for Disease Control and Prevention predicted that 42% of Americans could be overweight by 2030. Our expanding waistlines lead to not only a medical problem, but according to a recent article In The New York Times, it could also endanger personal safety in some situations—in an airplane crash, for example.

    The New York Times' Christen Negroni reports that engineers and scientists are questioning whether airplane seats are adequately constructed to protect overweight travelers. Government standards for airplane seat strength（强度）— first set moe than 60 years ago — require that the seats be made for a passenger weighing 170 pounds (77kg). Today, the average American man weighs nearly 194 pounds (88kg) and the average woman 165 pounds (75kg). Negroni reports:

    “If a heavier person completely fills seat, the seat is not likely to behave as intended during a crash,” said Robert Salazar, the leading scientist at the Center for Applied Biomechanics at the University of Virginia. “The energy absorption that is built into the aircraft seat is likely to be overpowered and the passengers will not be protected properly.”

    “Nor would the injury be limited to that passenger only,” Dr. Salzar said. “If a seat or a seat belt fails,” he said, “those people who are seated nearby could be endangered from 'the uncontrolled movements of the passenger'.”

    Most complaints about airplane seats focus on their lack of comfort and high ticket price, and whether overweight passengers should be made to buy two seats. But The New York Times' article brings up another reason to feel anxious about flying. Investigators of the issue got in touch with the airplane seat and seat belt makers, but they refused to comment on the problem. Experts agreed that crash testing should be done with overweight dummies （人体模型）. Both airplane seats and seat belts should be tested, they said.

    Fortunately, however, according to Nora Marshall, a senior adviser at the National Transportation Safety Board, the board's investigators have never seen an accident involving a commercial plane in which the weight of a passenger was a problem.

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    Biologists believe that love is fundamentally a biological rather than a cultural construct, because the capacity for love is found in all human cultures and similar behavior is found in some other animals. In humans the purpose of all the desire is to focus attention on the raising of offspring. Children demand an unusual amount of parenting, and two parents are better than one. Love is a signal that both partners are committed, and makes it more likely that this commitment will continue as long as necessary for children to reach independence. But what does science have to say about the notion of love at first sight?

    In recent years the ability to watch the brain in action has offered a wealth of insight into the mechanics of love. Researchers have shown that when a person falls in love, a dozen different part of brain work together to release chemicals that trigger feelings of euphoria, bonding and excitement. It has also been shown that the unconditional love between a mother and a child is associated with activity in different regions of the brain from those associated with pair-bonding love.

    Passionate love is rooted in the reward circuitry of the brain—the same area that is active when humans feel a rush from cocaine. In fact, the desire, motivations and withdrawals involved in love have a great deal in common with addiction. Its most intense forms tend to be associated with the early stages of a relationship, which then give way to a calmer attachment form of love one feels with a long term partner.

    What all this means is that one special person can become chemically rewarding to the brain of another. Love at first sight, then, is only possible if the mechanism for generating long-term attachment can be triggered quickly. There are signs that it can be. One line of evidence is that people are able to decide within a second how attractive they find another person. This decision appears to be related to facial attractiveness, although men may favor women with waist-to-hip ratio of 0.7, no matter what their overall weight is. (This ratio may indicate a woman's reproductive health.)

    Another piece of evidence comes from work by a psychologist at Ben-Gurion University, who found in a survey that a small percentage (11%) of people in long-term relationships said that they began with love at first sight. In other words, in some couples the initial favorable impressions of attractiveness triggered love which sustained a lengthy bond. It is also clear that some couples need to form their bonds over a longer period, and popular culture tells many tales of friends who become lovers.

    One might also assume that if a person is looking for a partner with traits that cannot be quantified instantly, such as compassion, intellect or a good sense of humor, then it would be hard to form a relationship on the basis of love at first sight. Those more concerned with visual appearances, though, might find this easier. So it appears that love at first sight exists, but is not a very common basis for long-term relationships.

    Happy Shakespeare Day!

    The 23rd April is World Book Day, but did you know that it is also Shakespeare Day? Everybody has heard of Shakespeare, but do you know many plays he wrote? Have you heard of many of his poetry?

    Shakespeare's plays fit into three categories: tragedies, comedies and histories. Perhaps his most famous play is the tragedy story of Romeo and Juliet, which deals with two young lovers who are forbidden to marry by their parents. Other tragedies include Hamlet, a play about a vengeful ghost Othello, about an army general who is manipulated(操纵) into killing his wife, and Macbeth(麦克白). If you've seen Harry Potterandthe Prisoner of Azkaban written which is sung in the Great Hall after the Sorting Ceremony. These words come from the Witches in Macbeth!

    Shakespeare's comedies include Much Ado About Nothing, A Midsummer Night's Dream and Twelfth Night. Twelfth Night is a play about confusing identities. Two twins are shipwrecked and the sister, Viola, dresses up as her brother, Sebastian, who she thinks is dead. It's hilarious, because the brother reappears without Viola realizing and there's a big love triangle going on: Viola is in love with the Duke Osino, who is in love with Olivia, who falls in love with Sebastian, except she doesn't realize that Sebastian is actually Viola dressed up! Everybody falls in love with the wrong person, but it is all made right in the end.

    The history plays, such as Antony and Cleopatra, Richard III and Henry V are based on the lives of real historical people. Antony and Cleopatra is a story about a doomed romance in ancient Egypt. Cleopatra becomes Antony's mistress and Antony becomes so obsessed with her that he loses his military might. Cleopatra kills self by letting a snake bite her after Egypt's army has been defeated by Octavius and Antony kills himself too.

    Shakespeare's plays can be very heavy going sometimes. Some of the themes they deal with are heavy and complex, so they almost always contain a lighter subplot with characters who aren't closely linked to the characters in the main plot. They are often used in tragedies to lighten the mood of the play and to keep the audience interested in the main plot.

    It may sound strange, but cutting down a real tree for Christmas is actually greener than going with the artificial kind, one scientist says.

    “It is a little confusing to people,” said Clint Springer, a biologist at Saint Joseph's University in Philadelphia. Because of concerns over deforestation（砍伐森林）around the world, many people naturally worry that buying a real tree might contribute to that problem. But most Christmas trees for sale these days are grown not in the forest but on tree farms for the purpose of being cut.

    Moreover, from the viewpoint of greenhouse gases, real trees are “the obvious choice”. Live trees actively release oxygen as they grow, and meanwhile remove carbon dioxide from the atmosphere. After they have been cut and Christmas is over, they're usually cut into smaller pieces for mulch（覆盖物）. As mulch, the bits of trees very slowly release carbon dioxide back into the atmosphere. So in the end, a real Christmas tree is carbon neutral, putting the same amount of carbon dioxide back into the air as it took out (although much more slowly).

    The tree farms that grow the trees also replant after the trees are cut.  Artificial trees, on the other hand, don't come out even in the carbon balance. Petroleum（石油）is used to make the plastics in artificial trees and lots of carbon dioxide-creating energy is required to make and transport them. Because these trees just end up in the places where waste is buried under the ground after use, “those greenhouse gases are lost forever,” Springer said.

    Gardening is a very popular hobby. And it is one that produces wonderful results – food for your dinner table and flowers for your home! Gardens themselves can be very beautiful. So you would think that a garden path is a great place to be. Well, in conversation, it is not. Leading someone up the garden path means you are trying to trick them. You are not trying to show them your beautiful flowers.

    Speaking of beautiful flowers, gardeners love to see small buds (芽) forming on their plants. Besides plants and flowers, people can bud, too. If a child is good at drawing and painting, we can call him a budding artist. So “budding” describes something that is beginning to develop.

    On the opposite end, you stop something from growing if you nip it in the bud. This is a common expression when we talk about stopping something bad and preventing it from continuing. It's good to nip small problems in the bud before they turn into big problems.

    Now flowers that bloom （开花）are beautiful to see – even garden-variety flowers. “Garden-variety” describes anything that is common and not so special. You can have a garden-variety cold—not a serious illness.

    Now, a problem that many gardeners have is weeds. Weeds grow easily and can quickly take over a garden. In conversation, we sometimes use “weeds” to mean too many details. So, if you are in the weeds, you are taken over by too many details.

    As we said, weeds grow quickly. So do children. So, we like to say a child grows like a weed. This expression compares a child's fast growth to that of a weed.

    It was a cold winter. The wind blew all night and the snow was blinding. When morning came, my three children and I got up and made our way to the windows. As we looked out of the window, we saw that the henhouse was gone. Our three hens had been blown away by the cold wind.

    I looked at the emptiness outside. Then I saw all three chickens sitting around the edge of a white bucket. I couldn't believe my eyes! How was this violent wind not blowing them into the field beyond？I quickly pulled on long snow pants and heavy winter coat, wrapped a scarf around my neck and stuck my feet into large boots.

    I shouted at the wind as it blew. I was alone, struggling in the snow. They stared out the window into the vast white sea of snow, peering at any sign of movement. Outside I heard the sound of my boots as I walked against the wind.

    As the snow circled around me, I steadily made my way to the soft cluck-cluck-cluck sound my hens always made. When I reached them, I saw that their little feet were holding on to the edge of the bucket, heads bent forward and away from the wind. I gently lifted each hen and put it carefully into the warm inside. Then I began the freezing walk back to the small shed directly behind our house. One by one I laid my chickens on the cold floor, and they began to cluck softly.

    As I shut the shed doors, my eyes went directly to the window where my children were watching. They jumped up and down cheering, and so did I! I wasn't some dragon slayer(屠龙者) from a fairy tale. I was simply a mom, but the look on my children's faces told me that they thought I was a hero mom.