We live in a sweet world. An average American kid consumes(消耗) more than 20 teaspoons of sugar per day, and adults eat 50% more sugar today than they did in the 1970s. We all know that too much sugar isn't good for us. Researchers at the University of Utah used mice to make a study to prove the toxic effects of eating more sugar. They found it could influence people's health seriously.

    During the 58-week-long study, mice were fed a diet containing 25% more sugar. This percentage is equal to a healthy human diet along with three cans of soda daily. The team found that these mice were twice as likely to die as mice without eating so much sugar. Though the mice did not show signs of obesity or high blood pressure, male mice produced 25% fewer offspring(后代) than the other mice.

The reason why mice were chosen for research by scientists is not far to seek. “Mice have the genetic(基因)structure similar to humans'. Most substances(物质) that are harmful to mice are also harmful to people; it's likely that those important physical problems that cause the rising death rate among mice can also influence people,” says the study author James Ruff of the University of Utah. Findings from this study reveal negative effects that are not as detectable as weight gain or heart problems. Sugar can contribute to long-term changes in the body that can affect development and even shorten lives.

    Different types of sugar have different effects on the human body. Some of the sugar we consume comes from foods we might expect—candy, soda, and cookies. But much of the sugar that we eat is hidden. Food companies add large amounts of sugar to items we may not classify as sweets. To help cut down extra sugar consumption, nutrition experts suggest looking at the ingredients on food packages. Cutting sugar out of the American diet altogether may be difficult, but making every effort to control our nation's desire for sugar will avoid a sweeter future.

    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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    You get on an almost-empty bus, but the next passenger decides to ignore all the empty seats to sit right next to you. While you are waiting in line at the supermarket, the next customer stands just behind you shouting into his phone.

    These are attacks of the personal space invaders(侵略者). Though preferences for personal space differ from culture to culture, we Britons do love our independence and personal space.

    As the British customs website Debrett has said, as a British person, somebody standing too close may make you “focus less on what somebody is saying than on how close they are to you”. Simple acts like putting an arm around someone you don't know that well may seem friendly in China, but they can make us very uncomfortable. The ediplomat.com website explains: “The British are not back slappers (拍打者) or touchers and generally do not show affection (喜欢) in public.”

    Being a British person around people from other countries can therefore be full of problems. People from many European countries such as France and Spain kiss each other on the cheek when they meet, yet to us this seems too friendly and “touchy-feely”.

    Simple matters like how close others stand can be problems to Britons who want to keep their own personal space. Giving advice on how to behave around a British person, Debrett's says that “if you can feel the warmth of their worried breath upon your face, then you're standing too close”.

    So, are British people unfriendly? No. The ediplomat.com website explains that we are not as “indifferent” as we may seem, but “very friendly and helpful to foreigners”. However, we do have different ideas about our own space to many people from other countries. Just let us know if you're going to come any closer than arm's length, and you'll be fine!

    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.

    Over millions of years, African penguins have developed a keen sense of where to find food. Once they're old enough, they set off from the shores on which they were hatched（孵化） for the first time and swim long distances in search of tasty fish like anchovies and sardines. But they don't search directly for the fish themselves. When African penguins head out to sea, they look for areas with low surface temperatures and high chlorophyll（叶绿素）. Because those conditions signal the presence of algae（藻类）. And lots of algae means lots of plankton（浮游动物）, which in turn means lots of their favorite fish. Well, that's what it used to mean.

    Climate change plus overfishing have made the penguin feeding grounds a mirage（海市蜃楼）. The habitat is indeed plankton﹣rich, but now it's fish﹣poor. Researchers call this an "ecological trap." "It's a situation where you have a signal that previously pointed an animal towards good﹣quality habitat. That habitat has been changed, usually by human pressures. The signal stays, but the quality in the environment gets worse."

    Richard Sherley, a zoologist at the University of Exeter and his team used satellite imaging to track the African penguins from eight sites along southern Africa. Historically, the birds benefited from tons of fish off the coasts of Angola, Namibia and western South Africa, but now they're going hungry.

    "I was really hoping we'd see them going east, and finding areas which the fish had moved to but it ends up being quite a sad story for the penguins." said Richard.

    The researchers calculate that by falling into this ecological trap, African penguin populations on South Africa's Western Cape have declined by around 80 percent.

    Some research groups are exploring the idea of moving them to a place where they can't get trapped, like the Eastern Cape. But Sherley thinks that a solution in the long run means making and carrying out rules to create more sustainable（可持续的） fishing industry, which needs public support.

    "When someone is rude to you, it can put you in a bad mood. It may even lead you to be rude to someone else, creating a chain of rudeness. In fact, this troubling chain may even be caused by simply seeing someone be rude to another person. You don't even have to be the target of the had behavior," stated a researcher.

    The researchers worked with 81 persons, with occupations ranging from security to business to medicine, who were asked to complete online surveys over a 10-day period. Participants recorded their moods when they woke up; and in the evening, they described their experiences over the course of that day.

    Each morning the participants also viewed a short video, describing workplace interaction of some kind. Half of the mornings, the video included some kind of rudeness while the other half had some kind of warm interaction in the workplace. Rudeness was conveyed through various means, including a lack of eye contact or unpleasant language.

    Participants who watched the rudeness videos reported seeing or experiencing rudeness during the day, and they were also more likely to escape from fellow employees to avoid being the victims of rudeness themselves. They reported their overall work suffered that day as a result.

    Not all participants were affected by the rudeness videos, however. A few weeks before the study began, the participants completed an evaluation that measured their self-confidence and emotional stability among other things. The participants who scored higher on this evaluation were significantly less likely to be influenced by the rudeness.

    Consequently, one of the researchers recommended that companies hire managers who can limit exposure to rudeness, provide plenty of positive reinforcement (强化) and build a civil workplace environment. This, in turn, could help employees build their confidence levels and help them better handle workplace rudeness.