According to body language expert Robert Phipps, the way people sleep at night actually determines a lot about the type of personality they have. Phipps has identified four sleeping positions that affect personality.

    Phipps found that worriers, those who stress the most, tend to sleep in the fetal (胎儿的) position. He found that this is the most common bedtime position, with nearly 58 percent of people sleeping on their side with knees up and head down. The more we curl up (蜷曲), the more comfort we are seeking, according to Phipps.

    The second most common position is the log. Sleeping with a straight body, with arms at each side, as if they are standing guard at Buckingham Palace, indicates stubbornness, and these people (the 28 percent who sleep this way) often wake up stiffer than when they went to sleep.

    “The longer you sleep like this, the more rigid your thinking is and you can become inflexible, which means you make things harder for yourself,” according to Phipps.

    Yearner (向往) sleepers are next on the list. About 25 percent of people sleep in this style—on their side with arms stretched out in front, looking as if they are either chasing a dream or perhaps being chased themselves. Yearners are typically their own worst critics, always expecting the best results, explained Phipps. These people often wake up refreshed and eager to face the challenges of the day ahead.

    Perhaps the most peculiar (奇怪的) of sleep styles is the freefaller position. This sleep style makes up 17 percent of the population. They sleep face down with arms stretched out. These people, according to Phipps, feel like they have little control over their life. Not only is this the strangest of sleep styles, but also the least comfortable, and people may wake up feeling tired and have no energy.

    Inconclusion, Phipps has only one more thing to add: “A good night's sleep set you up for the following day and our sleeping positions can determine how we feel when we wake.”

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    Most people know precious gemstones (宝石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It's more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone's origin.

    Beneath the surface of a gemstone, on the tiny level of atoms and molecules（分子）, lie clues (线索) to its origin. At this year's meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers (激光) to clarify these clues and identify a stone's homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.

    Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.

    To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles（微粒）called electrons separate from atoms.

    The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.

    In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.

    Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.

    Now many young people are traveling around the world on their own, not because they have no one to travel with, but because they prefer to go alone.

    Kristina Wegscheider from California first traveled alone when she was at college and believes that it is something everyone should do at least once in their life, “It opens up your mind to new things and pushes you out of your comfort zone.” Wegscheider has visited 46 countries covering all seven continents.

    In foreign countries, with no one to help you read a map, look after you if you get ill, or lend you money if your wallet is stolen, it is challenging. This is what drives young people to travel alone. It is seen as character building and a chance to prove that they can make it on their own.

    Chris Richardson decided to leave his sales job in Australia to go traveling last year. He set up a website, The Aussie Nomad, to document his adventures. He says he wished he had traveled alone earlier. “The people you meet, the places you visit, or the things you do, everything is up to you and it forces you to grow as a person,” said the 30-year-old man.

    Richardson describes traveling alone like “a shot in the arm”, which “makes you a more confident person that is ready to deal with anything”. He said, “The feeling of having overcome something on my own is a major part of what drives me each day when I'm dealing with a difficult task. I walk around with my head up because I know deep down inside that nothing is impossible if you try.”

    The great 19th century explorer John Muir once said, “Only by going alone in silence can one truly get into the heart of the wilderness.”

    Most people looking for ways to quit smoking worry about weight gain, and with good reason. Smokers who quit tend to pack on an average of 5 pounds after they stop smoking cigarettes. A new study, published by the journal Science, explains why this happens.

    The new research explains that nicotine appears to combine with appetite-regulating neurons (调节食欲的神经元) in the brain, besides the receptors (感受器) that bring about addiction. These neurons help regulate how much food gets consumed, but under the influence of nicotine, they lose their self-control. This is why when smokers quit, they tend to eat more and gain weight.

    The researchers believe that their discovery will lead to the development of drugs that aim at nicotine receptors on brain cells that control appetite. In the future, weight gain may no longer be a reason for smokers to delay the decision to kick the habit, but that's no reason to wait. Nicotine-replacement treatment, while not for everyone, can help. Here are a few more ways to quit smoking and stay slim.

    Drink water. To improve metabolic (新陈代谢的) rates, make half of those glasses ice water. Juice can be too high in calories, something you'll want to keep an eye on your journey toward being a slimmer non-smoker. Plan your snacks. Healthy snacks help keep your metabolism working, so you continue to burn calories while stopping wild hunger pain, or fake hunger.

    Keep moving. Exercise kills two birds with one stone. It helps you burn calories and prevents you from eating when you're not truly hungry. It's also a feel-good stress reliever (缓解物). Focus on your fitness and how being healthy makes you feel. Make exercise a goal and think of quitting as your reward for being physically fit.

    Thanks to this new hands- free suitcase, carrying around heavy luggage may soon become a thing of the past. Designed by Israeli company NUA Robotics, this "smart" suitcase can follow you everywhere you go.

    The carry­on suitcase, now a prototype(雏形), connects to a smartphone app via bluetooth. It has a built­in camera sensor that can "see" you and follow you around on flat floors. It comes with an anti­theft alarm to prevent someone carrying it away when you're not looking. "It can follow and carry things for people around while communicating with their smartphone, and avoiding bumping into other objects," explained Alex Libman, founder of NUA Robotics. "We're combining sensor network, computer vision, and robotics. So if you download our app(应用), press the 'follow me' button, the luggage recognizes its user and knows to follow and communicate."

    NUA is still testing the products and trying to improve features like speed and customization(客户订制), but they hope to make the suitcase available to customers in a year's time. If it proves successful, they want to use the bluetooth pairing technology to automate(自动化操作)lots of other products, like shopping carts at the supermarket. These products are especially meant to be useful to the physically disabled and elderly. "Any object can be smart and robotic," Libman told Mashable. "We want to bring robots into everyday life."

    The Israeli tech company made it clear that the finished product will look just like a common suitcase. They're planning to partner with a carry­on luggage maker, since the product that makes it "smart" weighs just 2.5 pounds and can be fitted on old­fashion luggage.

    With NUA's smart suitcase, carrying around heavy luggage isn't a burden. But how their invention will handle tough blocks like stairs? It will be interesting to wait.

    I can't remember the first time one of my children told me, "I hate you." I can, however, tell you that it still happens occasionally, but it doesn't bother me. As their father, I often say things that are unpopular. If they hate me once in a while, I know I'm doing a good job.

    There are three other words that I won't allow in my house, however. Last week, I was watching my older son play with a paper airplane. After he accidentally threw it into a wall and it came apart, his eyes welled up with tears.

    "I hate myself," he said. It wasn't the first time he'd said it, and I was concerned that he'd started to actually believe it.

    I knelt down next to him and made him look into my eyes. I told him that I never wanted to hear those words again, and that he needed to respect himself.

    The difference between your kid telling you they hate you and them saying they hate themselves is that, five minutes later, they've already forgotten they "hate you". Self-hate is much more potentially poisonous and for young people, it can linger into the rest of their life.

    Kids who start to believe they hate themselves sometimes struggle to form new friendships. As teenagers, they avoid the chance to connect with a potential love interest, because they assume they'll be rejected. And as adults, they might choose not to apply for the dream job because they assume it won't work out.

    I know this is true, because I didn't have a high opinion of myself as a child. I found myself struggling in many areas, and I'd hate to see my children suffer the same fate.

    Sometimes, words are just words. But some words can make the kind of impact I'd very much like to avoid for my children. I don't fear strong language; I fear language that makes us weak.