A recent study led by researchers from the National University of Singapore (NUS) has found a clear link between the color of a taxi and its accident rate. An analysis of 36 months of detailed taxi, driver and accident data from two fleets of yellow and blue taxis in Singapore suggested that yellow taxis have fewer accidents than blue taxis. The higher visibility (能见度） of yellow makes it less difficult for drivers to avoid getting into accidents with yellow taxis, leading to a lower accident rate.

    The study was led by Prof Ho. To test whether there was a relationship between the color of a taxi and the number of accidents the taxi had, the research team analysed data collected by the largest taxi company in Singapore. The researchers found that yellow taxis have about 6. 1 fewer accidents per 1,000 taxis per month.

    They also studied the economic effect of changing the color of the entire fleet of taxis to yellow. The Singapore taxi company involved in the study owns about 16,700 taxis in a ratio (比例) of one yellow to three blue taxis. If a commercial decision is made to switch from blue to yellow taxis, 76. 6 fewer accidents will occur per month or 917 fewer accidents per year.

    Assuming an average repair cost of $1,000 per car and a downtime of six days, the color of all taxis to yellow could produce an annual saving of $2 million.

    “We are eager to continue to validate (证实) the findings of our study by looking at the use of yellow in other types of public transport, such as school buses. For example, we hope to compare the accident rates of yellow school buses against those of other colors to find out if yellow is indeed a safer color for school buses. Besides, we' re also interested to look at private-hire vehicles and do a comparison of the accident rates of vehicles that are of different colors explained Prof Ho.

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    Mobile technology has created new ways for all types of learning styles to help discover new information. If you want to teach yourself things, here are some apps that will help you.

    Coursera

    Perhaps one of the biggest advancements in the history of e-learning, Coursera has teamed up with top school like Duke, Stanford, and John Hopkins to bring you direct access to real college courses in psychology, computer science, business, and technology. Each course features pre-recorded videos, projects, and quizzes, just like you'd receive inside the classroom.

    Lumosity

    This app features three-day sessions that target many different areas of brain activity: memory, speed, problem solving, and thinking flexibility. Each day you can participate in a timed session to sharpen mental intelligence and keep track of your progress over time.

    Duolingo

    If you've ever wanted to learn a new language but didn't know where to start or couldn't afford expensive apps, you need to check out Duolingo. This app teaches more than a dozen languages by breaking up exercises into mini games. The developer of Duolingo claims that 34 hours of learning in this app equals a full term's worth of school.

    EarthViewer

    Ever wonder what Earth looked like a million years ago? There's no better way to know than to look for yourself. Earth Viewer takes you on a digital journey to see how the landscape(地貌) and face of the planet has developed over the past 4.5 billion years, and view climate changes, sea level adjustments, or the evolution of famous cities.

Yawning（哈欠）sends out certain messages—either “Oh, this movie is boring" or "I probably need to get some sleep". But did you know that a yawn can also help your brain to cool down when it is so overheated?

    A new study, led by a research team of Princeton University, has indicated（表明）that yawning could be the brain's natural way of regulating temperature. People yawn more often when the temperature outdoors is lower than their body temperature but are less likely to yawn when it is hotter outdoors, according to Sciencedaily.com.

    The research team did an experiment on 160 people, 80 in summer and 80 in winter, to examine how often they yawned at different air temperatures. The study found that people yawned more often in winter than in summer. Scientists say that when the air temperature is lower outside the body, there is heat exchange between the overheated brain and the cool air. But when the air temperature is higher than or equal to the body, people are less likely to yawn because the hot air they breathe in will make the brain even hotter.

    When people yawn, their jaw is also stretched, which increases blood flow and may also help cool the brain.

    The study showed that the amount someone yawned could be related to the amount of time they spent outside. The longer they spent outside in summer, the less they yawn. Nearly 40 percent of participants yawned within their first five minutes outside, but after that the percentage was reduced to less than 10 percent.

    However, the result was the opposite in winter. The number of people who yawned increased when they spent more than five minutes outdoors. But the change was only slight compared to summertime.

    According to Gallup, this is the first report to show that yawning frequencies(频率) change depending on season. This could help us to understand better the way our brains work. It may also help us understand the reason why frequent yawning can sometimes be a sign of brain disease.

    A study showed that the experiences children have in their first few years are important. These experiences affect the development of the brain. When children receive more attention, they often have higher IQs. Babies receive information when they see, hear and feel things, which makes connections between different parts of the brain. There are a hundred trillion(万亿)connections in the brain of a three-year-old child.

    Researcher Judit Gervain tested how good newborns are at distinguishing different sound patterns. Her researchers produced images of the brains of babies as they heard different sound patterns. For example, one order was mu-ba-ba. This is the pattern"A-B-B". Another order was mu-ba-ge. This is the pattern “A-B-C”. The images showed that the part of the brain responsible for speech was more active during the" A-B-B" pattern. This shows that babies can tell the difference between different patterns. They also were sensitive to where it occurred in the order.

    Gervain is excited by these findings because the order of sounds is the building block of words and grammar." Position is key to language," she says. "If something is at the beginning or at the end, it makes a big difference: John caught the bear.' is very different from 'The bear caught John.'”

    Researchers led by scientist Patricia Kuhl have found that language delivered by televisions, audio books, the Internet, or smartphones－no matter how educational－doesn't appear to be enough for children's brain development. They carried out a study of nine-month-old American babies. They expected the first group who'd watched videos in Chinese to show the same kind of learning as the second group who were brought face-to-face with the same sounds. Instead they found a huge difference. The babies in the second group were able to distinguish between similar Chinese sounds as well as native listeners. But the other babies－regardless of whether they had watched the video or listened to the audio－learned nothing.

Time Travel

    If you could travel in time, where would you go? Perhaps you would watch an original performance of a Shakespeare's play in Elizabethan England? What about hanging out with Laozi in the Spring and Autumn Period? Or maybe you'd voyage far ahead of the present day to see what the future holds.

    The possibility of time travel is indeed appealing. Stories exploring the subject have been around for hundreds of years. Perhaps the best known example is science fiction novel. The Time Machine, which was written by H.G. Wells and published in 1895 for the first time. It was adapted into at least two feature films of the same name, as well as two television versions, and a large number of comic book adaptations. It is generally credited with the popularization of the concept of time travel using a vehicle that allows an operator to travel purposefully and selectively. The term "time machine", coined by Wells, is now universally used to refer to a vehicle transporting people into the far future.

    But could time travel actually be possible? Some scientists say yes, in theory. They propose using cracks in time and space called “wormholes”, which could be used as shortcuts to other periods. Einstein's theory of relativity allows time travel in extreme circumstances. And British physicist Stephen Hawking says you could travel into the future with a really fast spaceship going at nearly the speed of light. Though building such a spaceship would of course be no simple task.

    Even if you could travel into the past, there is something called the “grandfather paradox”. It asks what would happen if a time traveler were to go back in time and have his own grandfather killed for some reason, and therefore prevent himself from being born. If the time traveler wasn't born, how would he travel back in time?

    And would you really like to visit the future? In H.G. Wells' book, the main character travels into distant time where he arrives at a beach and is attacked by giant crabs. He then voyages 30 million years into the future where the only living thing is a black object with tentacles(触角).

    If that's what's in store, maybe we are better just living in the present day after all.