Breakthroughs in science and technology are paving the way for modern cities to support bigger populations. Now, we see the most exciting urban innovations to show you exactly how they'll improve your city's infrastructure(基础设施).

Lighting Up The Night

    Anthony Di Mari dreamed up an electric tree to help irrigate public parks and light them at night. These electric trees contain a special infill (填充物) that collects water from rainfall. The water is then distributed through a shallow underground irrigation system with the help from the trees' swaying movement. An electric motor turns energy from the waving of the artificial trees into electricity, which is used to light up the trees' outer LEDs.

Thinking Outside The Box

    As more people flock to urban areas, city planners will need to get increasingly creative about how to satisfy residents' health and transportation needs within decreasing available space. One way to achieve this is by updating infrastructure to support biking and walking by building suspended(悬浮的) roundabouts like hovering in the Netherlands. By lifting bicycle and pedestrian traffic above busy roadways, cities can significantly decrease over-crowded traffic condition.

Waving Hello To Clean Energy

    Cities that don't receive enough sunlight may find an attractive alternative in wave power. Since ocean waves rarely experience disruption(中断), electric engines driven by their clockwork push-and-pull can reliably provide power throughout the year. Further, thanks to advances in wave power technology, engineers have been able to move wave power engines farther offshore, where the waves pack the most punch, making the engines extremely efficient. So in the future, heavily populated coastal cities may use wave to meet their energy needs.

    When it comes to the Internet, people talk about the password most. Actually, it's been under fire for a long time. Research has shown that passwords are not a very good way to protect sensitive information.

    People would use some random characters, numbers and symbols. Furthermore, a unique password would be used for every site or application the user uses. Unfortunately, the longer and more complex passwords become, the more people are likely to forger them. Therefore, they use the same password for every service or application. These are all big no-noes and essentially defeat the purpose of a password.

    Google is trying to kill off passwords on Android devices by introducing the Trust API, which does what simple passwords cannot and gives developers a framework for securing their application using a number of security systems and metrics(衡量标准)on the device. A Trust Score will be generated based on a number of metrics including your device location, face scanning, fingerprints, and the things like your typing speed or the way you speak. Taken one at a time, these metrics are not secure. But taken together, these metrics will help recognize the real “you”.

    The good news is that Google has already been testing this on real world data. Google has proven the Trust API works. Next Google will run tests will some banks to see if the Trust API meets their needs before rolling out the system on Android phones later. It may take another year for apps and popular sites to start using the Trust API.

    This is a pretty exciting change. Passwords have been around for a lone time. Although the security of systems has been improved, the usability of systems hasn't been proved much. Google appears to have the best of them. Maybe that never-ending conflict between security and convenience will be able to take a break once the Trust system comes out.

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Welcome to the Kids' Science Challenge!

    Do you like science projects and winning some awesome gifts? This is the challenge for you. What's even better is that you don't have to build anything--simply come up with an original idea or design that relates to one of three topics given below.

Wonderful Sounds

    Ready for Wonderful Sounds? Click on Science Secrets to meet our sound specialist. And be sure to download fun activities with crazy new sounds and musical instruments in the Dig In section! Now what kind of new musical instrument can you invent?

Super Material for Sports

    Ready for Super Material for Sports? You'll discover the amazing world of Materials Science, where scientists and engineers develop new materials for everyday functions--like sports! Click on Science Secrets for information about our scientist. And don't forget to download the fun activities in the Dig In section! Now can you come up with a new sports material that would help you play your favorite sport?

Magical Microbes

    Ready to discover Magical Microbes, the tiniest living things on earth? Click on Science Secrets for information about our scientists. And be sure to download all the fun activities in the Dig In section! Now can you think of a brand new way that microbes can help people?

    Would it surprise you to learn that, like animals, trees communicate with each other and pass on their wealth to the next generation?

    UBC Professor Simard explains how trees are much more complex than most of us ever imagined.

    Although Charles Darwin thought that trees are competing for survival of the fittest, Simard shows just how wrong he was. In fact, the opposite is true: trees survive through their co-operation and support, passing around necessary nutrition “depending on who needs it”.

    Nitrogen (氮) and carbon are shared through miles of underground fungi (真菌) networks, making sure that all trees in the forest ecological system give and receive just the right amount to keep them all healthy. This hidden system works in a very similar way to the networks of neurons (神经元) in our brains, and when one tree is destroyed, it affects all.

    Simard talks about “mother trees”, usually the largest and oldest plants on which all other trees depend. She explains how dying trees pass on the wealth to the next generation, transporting important minerals to young trees so they may continue to grow. When humans cut down “mother trees” with no awareness of these highly complex “tree societies” or the networks on which they feed, we are reducing the chances of survival for the entire forest.

     “We didn't take any notice of it,” Simard says sadly. “Dying trees move nutrition into the young trees before dying, but we never give them chance.” If we could put across the message to the forestry industry, we could make a huge difference towards our environmental protection efforts for the future.

    Dyslexia(失读症) is a learning disorder, it interferes with the ability to recognise words, and for some readers to understand what they have read.

    Experts say dyslexia affects about five to ten percent of the population of the United State. Researchers have long known that people with dyslexia write or read words and letters backwards in the wrong order.

    But a new study shows that people with dyslexia may have trouble redirecting(重新传入) their attention between senses, from seeing something to hearing something. The study suggests something that might help dyslexic people learn more quickly — play video games.

    Vanessa Harrar of Britain's University of Oxford led the study. She reported the findings in the journal Current Biology. The study suggests that dyslexic people may have trouble moving quickly from what they read to what they hear. Doctor Harrar calls this a "sluggish shifting of attention across the senses."

    "So, if you are trying to read something and then trying to listen to somebody who's reading aloud and you're trying to follow along with what they are reading -- they have to switch their attention from hearing what they are saying to looking at the piece of paper and back again. So we found they have quite sluggish shifting of attention across the senses," said Harrar.

    In the study, Doctor Harrar tested 17 people with dyslexia, and 19 others without reading problems. The volunteers were asked to push a button as quickly as possible when they heard a sound, saw a light or experienced both together. Doctor Harrar compared the speed of their reactions.

    She found that people with dyslexia were just as fast as the others when they saw only a picture or heard only a sound. But the dyslexics had a slower reaction time when they heard a sound and saw a picture at the same time.

    Doctor Harrar feels like playing action video games could help dyslexic people shift from seeing to hearing more quickly. She adds that images in video games force the eyes to move and focus quickly.

    "Video game types of things pop out of here and there, they move your eyes around the screen quite quickly in response to things quite quickly, and the more you play a video game the faster you get that kind of thing. So, the video game is really training the attention system to move quickly," said Harrar.

    The study also shows that dyslexic people have the most difficulty going between what they saw and what they heard, this may have an effect on how dyslexic children are taught how to read.

    When children learn the alphabet, they usually see the letter first and then hear the sound, or they see and hear the letter at the same time. The study shows that dyslexics might learn more quickly if they hear the sound of a letter or word first before seeing it.

    Animals, including insects, do not have a language like ours. They do not talk to each other in words and sentences. But if we watch them, we can see that they do have ways of communicating with each other.

    Can you see the rabbits' tail? When rabbits see this white tail moving up and down, they run too. The rabbit has reminded them of potential dangers without making a sound. It has given them a signal.

    Many other animals use this kind of language. When a cobra(眼镜蛇) is angry, it raises its hood(兜帽) and makes itself look fierce. This warns other animals. When a bee has found some food, it goes back to its home. It cannot tell the other bees where the food is by speaking to them, but it does a little dance in the air. This tells the bees where the food is.

    Some animals say things by making sound. A dog barks, for example, when a stranger comes near. A cat purrs(猫的呜呜声) when pleased. Some birds make several different sounds, each with its own meaning. Sometimes we human beings speak in the same way. We make sounds like “Oh” or “Ah!” when we are frightened or pleased or when we drop something on our toes.

    But we have something that no animals have a large number of words which have the meanings of things, actions, feelings or ideas. We are able to give each other all kinds of different information in words and sentences, which no other animals can do. No other animals have so wonderful a language as we have.