Computers have beaten human world champions at chess and, earlier this year, the board game Go. So far, though, they have struggled at the card table. So we challenged one AI to a game.

    Why is poker(扑克) so difficult? Chess and Go are “information complete” games where all players can see all the relevant information. In poker, other players' cards are hidden, making it an “information incomplete” game. Players have to guess opponents' hands from their actions—tricky for computers. Poker has become a new benchmark for AI research. Solving poker could lead to many breakthroughs, from cyber security to driverless cars.

    Scientists believe it is only a matter of time before AI once again vanquishes humans, hence our human-machine match comes up in a game of Texas Hold's Em Limit Poker. The AI was developed by Johannes Heinrich, researcher studying machine learning at UCL. It combines two techniques: neural(神经的) networks and reinforcement learning(强化学习).

    Neural networks, to some degree, copy the structure of human brains: their processors are highly interconnected and work at the same time to solve problems. They are good at spotting patterns in huge amounts of data. Reinforcement learning is when a machine, given a task, carries it out, learning from mistakes it makes. In this case, it means playing poker against itself billions of times to get better.

    Mr Heinrich told Sky News: “Today we are presenting a new procedure that has learned in a different way, more similar to how humans learn. In particular, it is able to learn abstract patterns, represented by its neural network, which allow it to deal with new and unseen situations.”

    After two hours of quite defensive play, from the computer at least, we called it a draw.

    We brush our teeth daily, but do you know everything you need to know about dental care and hygiene? Believe it or not, there is a lot more than most people realize. Luckily, here are several apps that can help you.

●Brush DJ

    You should brush your teeth for full two minutes as recommended by dentists, but that time can be difficult to judge. Many recommend you listen to music, because many songs are just around two minutes in length. Brush DJ has loads of great tunes that will get you into the two­minute habit. There are both songs to listen to, and videos to watch, and you'll find a variety of awesome tunes.

●Orasphere

    It's recommended that Orasphere videos be used by dentists for their patients, so they can learn about procedures. Those who do use these videos say that the software can greatly decrease the amount of time it takes to explain procedures to patients.

●American Dental Association(ADA)

    Everything you ever wanted to know about your teeth, and then some, can be found on the American Dental Association(ADA) website. You'll find loads of great articles that have the latest news about dentistry（牙科）. Those interested in dental careers will find plenty of information to head them in the right direction, and there's even a section devoted to public dental programs, including Give Kids a Smile and Fluoride in Water.

●DDS GP

    Here is more presentation software that explains all types of dental procedures. This is helpful for dentists to have, because they can better explain procedures to their patients.

●Dentistry IQ

    You can find information for dentists, hygienists, assistants, office managers, and more at Dentistry IQ. You can also get information about new products, clinical practices, and much more. In addition, you can learn about career opportunities, the most recent practices, and a whole lot more.

    Below is a selection from a popular science book.

    If blood is red, why are veins（静脉） blue?

    Actually, veins are not blue at all. They are more of a clear, yellowish color. Although blood looks red when it's outside the body, when it's sitting in the vein near the surface of the skin, it's more of a dark reddish purple color. At the right depth, these blood-filled veins reflect less red light than the surrounding skin, making them look blue by comparison.

    Which works harder, you heart or your brain?

    That kind of depends on whether you're busy thinking or busy exercising. Your heart works up to three times harder during exercise, and shifts enough blood over a lifetime to fill a supertanker. But in the long run, your brain probably tips it, because even when you're sitting still your brain is using twice as much energy as your heart, and it takes four to five times as much blood to feed it.

    Why do teeth fall out, and why don't they grow back in grown-ups?

    Baby (or “milk”) teeth do not last long; they fall out to make bigger room for bigger, stronger adult teeth later on. Adult teeth fall our when they become damaged, decayed and infected by bacteria. Once this second set of teeth has grown in, you're done. When they're gone, they are gone. This is because nature figures you're set for life, and what controls regrowth of your teeth switches off.

    Do old people shrink as they age?

Yes and no. Many people do get shorter as they age. But, when they do, it isn't because they're shrinking all over. They lose height as their spine（脊柱） becomes shorter and more curved due to disuse and the effect of gravity(重力). Many (but not all) men and women do lose height as they get older. Men lose and average of 3-4 cm in height as they age, while women may lose 5 cm or more. If you live to be 200 years old, would you keep shrinking till you were, like 60 cm tall, like a little boy again? No, because old people don't really shrink! It is not that they are growing backwards —- their legs, arms and backbones getting shorter. When they do get shorter, it's because the spine has shortened a little. Or, more often, become more bent and curved.

    Why does spinning make you dizzy（眩晕的）?

    Because your brain gets confused between what you're seeing and what you're feeling. The brain senses that you're spinning using special gravity-and-motion-sensing organs in your inner ear, which work together with your eyes to keep your vision balance stable. But when you suddenly stop spinning the system goes out of control, and your brain thinks you'removing while you're not.

    Where do feelings and emotions come from?

Mostly from an ancient part of the brain called the limbic system. All mammals have this brain area —- from mice to dogs, cats, and humans. So all mammals feel basic emotions like fear, pain and pleasure. But since human feelings also involve other, newer bits of the brain, we feel more complex emotions than any other animal on this planet.

    If exercise wears you out, how can it be good for you?

    Because our bodies adapt to everything we do to them. And as far as your body is concerned, it's “use it, or lose it”! It's not that exercise makes you healthy, it's more that a lack of exercise leaves your body weak and easily affected by disease

    To fight for the conservation of forest ecosystem, several ecologists including Daniel Janzen convinced Del Oro, an orange juice producer, to donate part of their forestland to a national park. In return, Del Oro was allowed to throw large amounts of waste in the form of orange peels (皮) on a 3-hectare piece of land within the national park at no cost. Dealing with tons of leftover peels usually involved burning them or paying to have them poured into a landfill, so the proposal was very attractive.

    But a year later, another juice company challenged the deal in court, arguing that their competitor was “polluting a national park”. They ended up winning, and the deal between Del Oro and the national park fell through.

    Then in 2013, while discussing possible research avenues with Timothy Treuer, Daniel Janzen mentioned the orange story. Feeling interested, Treuer decided to stop by that piece of land that had been covered with fruit waste 15 years earlier. What he found shocked him.

    “While I would walk over exposed rock and dead grass in the nearby fields, I'd have to climb through undergrowth and cut paths through walls of vines (藤) in the orange peel site itself.” said Timothy Treuer.

    Treuer and his team spent months picking up samples (样品), analyzing and comparing them. They found great differences between the areas covered with orange peels and those that were not. The area with orange waste had richer soil.

    The effect that the orange peels had on the land is probably not that surprising to people familiar with composting (施肥), but what is really shocking is that a judge actually thought the waste of orange “mined” a national park and stopped it from going forward. Now that Timothy Treuer's study has received worldwide attention, this type of “ruining” is being seriously considered as a way of bringing forests back to life.

    She was returning from teaching out in a small community. It was a black, moonless night, and a heavy snow was falling.

    She thought back to the time when she had first started teaching out in small communities. During those days she had always picked up hitchhikers (搭便车者), until the day her sister told her that one of her friends had been shot in the head by a hitchhiker, all because she had stopped out of kindness to help him during a storm.

    Her family didn't stop worrying about her safety over the hitchhikers until the family heard the promise: “No more hitchhikers!” The snow that night was making her think back to this.

    Then she saw a man waving. She slowed down for him, but as he ran toward the car in the dark, she shook with fear. Yet she thought that if he was truly in need, she couldn't leave him here in this storm.

    The stranger explained that his car was dead, and she told him to get in. They drove for an hour into the next city and she took him to a convenience store. She waited until he had made a call. When he reported back to her that a family member would soon come to pick him up, she wished him well and then left.

    Tears fell on her cheeks as she drove away. It felt as though she had been holding her breath for an hour.

    “I hope they'll understand why I had to break my promise,” she thought.

Improve your reading, writing and math skills

    Through the Literacy and Basic Skills program, you will learn reading, writing, math and other basic skills (e. g. computer) to help you prepare for:

    ● employment

    ● college studies

    ● independence

    ● school credit

    These courses(课程) are free and available in English or French. There are courses designed for local people and Deaf people as well.

    Requirements(要求)

    To take these courses you have to:

    ● be an Ontario resident

    ● be 16 years old or older

    ● have reading, writing and math skills below the grade 12 level

    Learn in a classroom

    You can take these free classroom courses at more than 300 locations across the province.

    Find out more by contacting Employment Ontario.

    Learn online

    You can also learn online as one way of the Literacy and Basic Skills program.

    Four different organizations in Ontario offer free online courses tailored to you. Find out more about learning online:

    ● in French

    ● in English

    ● as a local person

    ● as a Deaf person