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    Have you ever wondered why the roots of the plants always know which way to grow—into the soil but not above it? Some British scientists have recently solved this mystery.    

      It turns out that roots have special hairs that tie them into the soil and help them grow their way past obstacles, a team at the John Inners Center in Norwich reports in the February 29 issue of Journal Science.

    "The key is in the fuzzy(有绒毛的) coat of hairs on the roots of plants," says professor Liam Dolan. "We have found a growth control system that enables these hairs to find their way and to become longer when their path is clear."

    Root hairs explore the soil in much the same way a person would feel their way in the dark. If they come across an obstacle, they make their way around until they can continue growing in an opening. I the meantime, the plant is held in place as the hairs grip the soil.

    The hairs are guided by a clever chemical trick. A protein(蛋白质) at the tip of the root hairs called RHD2 helps them to take calcium(钙) from the soil. Calcium makes the hairs grow, and produce more RHD2, and take more calcium.

    But when an obstacle blocks the hair's path, or the hair reaches the surface of the soil, the cycle is broken and growth starts in another direction.

    This system gives plants the flexibility to explore a complex environment and to live in even the most unpromising soils, says Dolan.

    In poor soils such as in parts of Australia and Africa, native plants have adapted by producing enormous numbers of root hairs. A better understanding of this adaptation will allow scientists to develop hairy rooted crops that can grow in unfriendly environments.

    According to Dolan, "Research in the John Inners Center is taking a breeding approach(育种方法) to increase hair length in wheat but it will be some time before new cultivars(栽培变种) are developed."

    The next time you go grocery shopping, try speaking to other customers. One summer day, I took a smile and a warm heart into a small store in Oregon and got far more than groceries.

    I love fresh produce(农产品) in the store, and not just for the amazing colors provided by summer's bounty (慷慨) or the chance to joy over new choices from other countries. It's also because I just love watching people pick their produce.

    The day I was there I found a sale on amazing cherry tomatoes—along with a woman in her late 70s. Despite the fact that we were strangers, we began to discuss apples. She noted a problem with the Pink Ladies. "They tasted like I was eating an unripe green apple from the tree," she said, twisting her face as if still tasting the sour apple.

    I wondered if this is something most of my generation can even remember doing. I surely do. I mentioned that I often could not resist the green yet tempting fruit swinging from an apple tree. This was the start for a series of discussions as we shopped-covering such topics as nutrition, new foods and the quality of produce.

    By this time a third woman had joined in our conversation. The three of us continued along, unexpected friends, chatting about family size and the troubles a mom might have serving healthful foods that please the whole family.

    Eventually we all went our separate ways, but in the dairy(奶制品) section I heard a small voice say, "I finally caught up with you." It was the first woman I'd talked to, extending a bag of apricots(杏) to me. "I don't know if your family will eat these," she added, "but they have a super deal on them."

    Again I was brought back to my childhood, when I also ate apricots straight from the tree. My mouth watered at the remembered flavor.

    The old lady didn't realize that she'd given me far more than produce. With that offering came a sense of community, a flashback to days when it was OK to talk to a stranger. She brought back memories of summer fruits right from the tree—and a feeling that somehow those apricots were a thank-you for sharing my time with her in a very unlikely place.

    Don't you just hate it when you have to take an important phone call and you're surrounded by potential eavesdroppers(潜在偷听者)? You either have to whisper or go outside to keep the conversation private, which is not good. Now Hushme aims to fix this problem by muffling your voice and making you look like Bane in the film Batman.

    Hushme is a strange high-tech mask(口罩)that blocks the sound of the wearer's voice so that people nearby can't hear what is being said. It connects to your phone via Blucetooth and comes with a pair of earphones. When you get a private call, all you have to do is put the mask on and it will do the rest. The pair of thick pads over your mouth does a good job of muffling your voice, but to ensure nothing gets through. Hushme also has speakers that play a variety of sounds when you speak.

    The Hushme mask, which comes in a variety of colors, can be worn around the neck, like a regular pair of earphones, and attaches in front of your mouth thanks to a couple of very powerful magnets(磁铁). It's not yet clear how comfortable speaking with this Bane-like mask over your mouth really is, or how effective its speech muffling ability is, so we know so far is that it makes you look strange. The sound choices for covering your voice currently include wind, ocean, rain, birds, monkey, but new ones could be added in the future.

    Advertised as the “world's first voice mask for mobile phones'. Hushme was showed at CES. At the becoming of this year. Its makers plan to sell it by the end of this year. It will cost about $200.

    As if 2016 hadn't been hard enough for China's workforce, a yearly survey has revealed that more than half of the country's white-collar employees got no year-end bonus ahead of the upcoming and costly lunar(农历的) New Year holiday. The survey of 11,500 workers by Chinese employment agency Zhaopin found that 50.9 per cent did not get an annual bonus at the end of 2016. Another 9.6 percent were told their bonuses had been delayed until after the New Year holiday.

    Before the slowdown that began in 2014, employers in China had been less ungenerous with cash bonuses, which can total well over a full month's pay and send employees back home for the holiday with plenty of cash for gifts to elders and other family members or to put away as savings. The impact of weak growth on year-end bonuses may have reached the highest point in 2015, however, when 66 per cent of white-collar workers received no year-end bonuses. And the 2016 level actually represents an improvement from 2014, when 61 per cent had to go without.

    But that recovery has also seen the size of bonuses drop: last year the average bonus was Rmb 12,821（$1,861）, about Rmb 2,000 more than that in 2015 but still about Rmb800 below the 2014 average. More than a quarter of those surveyed who saw their bonuses drop last year blamed the drop on poor company performance.

    Differences among the 34 cities surveyed were still greater, as the average bonus of over Rmb 15,800 in Beijing was more than three times than that in the lowest-paying city of Shenyang. Employees of state-owned firms also expressed more satisfaction with their bonuses than those at private companies — and little wonder, as the average bonus at the former was Rmb 17,318, or about Rmb 6,000 more than what private companies' employees could expect.

    But the impact of companies' stinginess(吝啬) can go beyond simply ruining employees' New Year holiday, possibly coming back to affect employers: 39 percent of respondents said they would look for work elsewhere if their year-end bonus was not returned to normal, an increase of 2.3 Percentage points from 2015.

    If you want to convince the boss you deserve a pay rise or promotion, the solution could be simple — eat the same food as they do. Psychologists have discovered managers are much more likely to instantly trust us if we choose the same dishes as them.

    During experiments, discussions over wages and work conditions were much more successful if both sides chose to snack on the same treats. And shoppers were much more likely to buy a product advertised on TV by someone eating a similar food to them at the time.

    The reason is thought to be so-called similarity attraction theory — where people tend to like others who have similar tastes or habits to themselves. But this is believed to be one of the first studies highlighting the role of food in this relationship. Researchers at Chicago University in the US conducted a series of experiments to examine food's role in earning trust.

    In a test, participants were told to watch TV — where someone pretending to be a member of the public praised a certain product. The volunteers were given Kit Kat bars to nibble (咬), while the TV people ate either a Kit Kat or grapes as they talked.

    The results showed viewers were much more likely to express an interest in buying the product if the TV showed the other person eating a Kit Kat too.

    The researchers added, “Although similarity in food consumption is not a sign of whether two people will get along, we find consumers treat this as such. They feel more trusting of those who consume as they do. It means people can immediately begin to feel friendship and develop a bond, leading to smoother transactions (交易) from the start.”

    Harley Street psychologist Dr. Lucy Atcheson said it was already known that wearing similar clothes could instantly create trust. But this was the first report that food had the same effect. She said, “This is really interesting. It makes sense as people feel they have common ground and can trust the other person. That means negotiations are more likely to be successful.”

    Self-driving cars have been backed by the hope that they will save lives by getting involved in fewer crashes with fewer injuries and deaths than human-driven cars. But so far, most comparisons between human drivers and automated vehicles have been unfair. Crash statistics for human-driven cars arc gathered from all sorts of driving situations and all types of roads. However, most of the data on self-driving cars' safety have been recorded often in good weather and on highways, where the most important tasks are staying in the car's own lane and not getting too close to the vehicle-ahead. Automated cars are good at those tasks, but so are humans.

    It is true that self-driving cars don't get tired, angry, frustrated or drunk .But neither can they yet react to uncertain situations with the same skill or anticipation of an attentive Unban driver. Nor do they possess the foresight to avoid potential dangers. They largely drive from moment to moment, rather than think ahead to possible events literally down the road.

    To a self-driving car, a bus full of people might appear quite similar to an uninhabited field. Indeed, deciding what action to take in an emergency is difficult for humans, but drivers have sacrificed themselves for the greater good of others. An automated system's limited understanding of the world means it will almost never evaluate (评估)a Situation the same way a human would. And machines can't be programmed in advance to handle every imaginable set of events.

    Some people may argue that the promise of simply reducing the number of injuries and deaths is enough to support driverless cars. But experience from aviation(航空)shows that as new automated systems are introduced, there is often an increase in the rate of disasters.

    Therefore, comparisons between humans and automated vehicles have to be performed carefully. To fairly evaluate driverless cars on how well they fulfill their promise of improved safety, it's important to ensure the data being presented actually provide a true comparison. After all, choosing to replace humans with automation has more effects than simply a one-for-one exchange.