Ever feel like you've been hit on the head after a bad night's sleep? According to scientists, the thought isn't as unbelievable as it seems.

    A study found going without sleep for just one night causes changes in the brain similar to those that occur after a blow to the head. The researchers said the healthy young men examined in the study showed a sudden increase in the same chemicals which indicate brain damage. Professor Christian Benedict, of Uppsala University, Sweden, explained that the chemicals NSE and S-100B are biomarkers for brain damage, such as concussion(脑震荡). He said, "What we found was their levels in the blood rose in the group that went without sleep for a night. This was not to the extent that would happen after a head injury, for instance, but it was still significant. During sleep, the brain cleans poisonous substances off itself."

    Benedict also said previous studies which linked a lack of sleep with increased risk of Alzheimer's, Parkinson's and multiple sclerosis could applaud his study. The rise of the chemicals in the blood after sleep loss may suggest not getting enough sleep contributes to a loss of brain tissue, he explained. Benedict, whose study is published in the journal Sleep, added, "In conclusion, the findings of our experiment indicate a good night's sleep may be critical to maintaining brain health."

    A third of the UK population suffer from sleep-related problems, while the average person now sleeps for only seven hours a night, compared with almost nine a few decades ago. Many scientists believe irregular sleeping patterns lead to illnesses ranging from aches and pains to heart disease, while less than eight hours' sleep a night can lower the IQ the next day.

    Baby girls make their way to dolls as soon as they can crawl, while boys will head for the toy cars,  a study has shown. The findings, the first to show consistent differences in very young babies, suggest there is a biological basis to their preferences.

    Psychologists Dr Brenda Todd from City University London carried out an experiment involving 90 babies aged nine months to 36 months. They were allowed to choose from seven toys. Some were boys' toys - a car, a digger, a ball and a blue teddy.  The rest were girls' toys: a pink teddy, a doll and a cooking set. They were placed a meter away from the toys, and could pick whichever toy they liked. Their choice and the amount of time they spent playing with each toy were recorded.

    Of the youngest children (nine to 14 months), girls spent much longer playing with the doll than boys, and boys spent much more time with the car and ball than the girls did. Among the two-and three-year-olds, girls spent 50 percent of the time playing with the doll while only two boys briefly touched it. The boys spent almost 90 percent of their time playing with cars, which the girls barely touched. There was no link between the parents' view on which toys were more appropriate for boys or girls, and the children's choice.

    Dr Brenda Todd said: “Children of this age are already exposed to much socialization. Boys may be given ‘toys that go' while girls get toys they can care for, which may help shape their preference. But these findings agree with the former idea that children show natural interests in particular kinds of toys. There could be a biological basis for their choices. Males through evolution have been adapted to prefer moving objects, probably through hunting instincts（本能）, while girls prefer warmer colors such as pink, the color of a newborn baby.”

    US president Donald Trump has popularized the phrase “fake news” But not too long ago these words in combination would have meant little to everyday English speakers.

    Anatoly Liberman, a German, writes about the origins of the word “fake”. The word, it turns out, has a very dark past. The best guess for how “fake” became mainstream, argues Liberman, is that it was a kind used by thieves in the London underworld. But“how it got there, nobody in the world knows, and probably nobody will ever know,” he tells Quartz.

    Liberman is a professor at the University of Minnesota and the author of Word Origins and How We Know Them. He writes that early records of “fake” as an English adjective appeared around the middle of the 18th century. The word likely comes from cant, or thief jargon(行话).

    The OED mentions “fake” as a verb starting in 1819, which basically meant'to do”in jargon, but also“to kill , wound, or rob”. An entry from a dictionary that year reads :

    “To fake any person or place, to rob them ;to fake a person may also imply to shoot, wound, or cut; to fake a man out and out, is to kill him.”

    Liberman traces the word next to Chares Dickens, who used “cly-faker”，where “cly” means pocket, in Oliver Twist. This is how he believes knowledge of “fake”as a word that means to steal, spread. Eventually it became a commonplace English word.

    If you are a teacher, join Youngzine and sign up your class for free today! Youngzine is an online News Magazine for school age children. It provides an educational, entertaining, yet safe way for kids and adults to get the latest news from around the world.

    Many educators have said that Youngzine is a perfect complement to academic material, and can be a great resource for teachers and their classes. Learning through current events not only makes students more aware of what's going on in the world, but also helps absorb concepts better.

    Moreover, Youngzine now provides a safe “blog” environment for classrooms—a constructive, creative and controlled way for teachers to create classroom assignments (任务) and push for discussions on current events!

    Youngzine provides special features just for you. If you sign up as a teacher:

    Each of your classes get a “Classroom Code” that identifies the students in that class. For each class, you get a “Blog” where you can post assignments and have students respond. You can include specific articles and quizzes in each assignment.

    For each of your classes, you get to see a foil report of each student's activities just by going to your classroom tab (标签): their comments, assignment, responses, points and quiz results.

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    One of the biggest problems when we are talking is the awkward silence. Encountering this situation is so uncomfortable that you would avoid meeting new people in the first place. In the past, I struggled with this and I even thought it had to do with my DNA or something… But later I learned that once you know how to keep those words flowing, you can meet and talk to anyone you like, which helps create great possibilities for friendship, fun and shared activities that you would otherwise have missed out on.

    After studying this in depth, I had different opinions and found that one of these common behaviors is the habit of filtering (过滤)--holding back from saying something until you've "checked" to make sure that what you're about to say is cool, impressive and interesting. Another problem is not learning to get in the mood for conversation. If you don't know how to change from subjects, then it can take a lot of time to warm up.

    It is the reflex (习惯性思维) that allows you to say whatever goes on in your mind. It's fun to realize that you're allowed to say whatever is on your mind. As long as you don't say anything that could land you in jail (监狱).

    All of the "Oh! That's interesting…" "Hmm, I've never heard of that" "Hmm, cool!" expressions are reactionary (保守的) bits of conversation that prove to the other person that you're really listening. This works 99% of the time. So, if you show some interest, they'll hang around and want to talk to you even more.

    Everyone knows that stories juice-up conversations, but most people only talk about stories of their own lives. When someone mentions something related to any of them, just tell the story, even if it's not from your life. The more interesting, stranger or more frightening they are, the harder they are to forget.

    Who is smarter? A human being or artificial intelligence?

The question swept the world last week when a Google-developed program called AlphaGo defeated the world top player, South Korean Lee Se-dol, 4-1.

    So, what comes next?

    Some people have been arguing that artificial intelligence, or AI in short, will be a bad thing for humans. In an interview with the BBC in 2014, UK scientist Stephen Hawking warned that “The development of full artificial intelligence could mean the end of the human race.”

    So are we really about to live in the world shown in the Terminator movies?

    “Not quite,” answered The Economist. After all, it's not hard to get a computer program to remember and produce facts. What is hard is getting computers to use their knowledge in everyday situations.

    “We think that, for the human being, things like sight and balance(视觉平衡), are natural and ordinary in our life.” Thomas Edison, founder of Motion Figures, a company that is bringing AI to boys, told the newspaper. “But for a robot, to walk up and down just like human beings requires various decisions to be made every second, and it's really difficult to do.”

    As The Economist put it, “We have a long way to go before AI can truly begin to be similar to the human brain, even though the technology can be great.”

    Meanwhile, John Mark off of The New York Times said that researchers should build artificial intelligence to make people more effective.

    “Our fate is in our own hands,” he wrote. “Since technology depends on the values of its creators, we can make human choices that use technology to improve the world.”