After a terrible electrical accident, which caused him to become both blind and deaf, the whole world became completely dark and quiet for Robert Edwards for almost ten years. The loss of sight and hearing threw him into such sorrow that he tried a few times to put an end to his life. His family, especially his wife, did their best to tend and comfort him and finally he regained the will to live.

    One hot summer afternoon, he was taking a walk with a stick near his house when a thunderstorm started all at once. He stood under a large tree to avoid getting wet, but he was struck by the lightning. Witnesses thought he was dead but he woke up some 20 minutes later lying face down in muddy water at the base of the tree. He was trembling badly, but when he opened his eyes, he could hardly believe what he saw：a plough and a wall. When Mrs. Edwards came running up to him，shouting to their neighbors to call for help，he could see her and hear her voice for the first time in nearly ten years.

    The news of Robert regaining his sight and hearing quickly spread, and many doctors came to examine him. Most of them said that he regained his sight and hearing from the shock he got from the lightning. However, none of them could give a convincing answer as to why this should have happened. The only reasonable explanation given by one doctor was that, since Robert lost his sight and hearing as a result of a sudden shock, perhaps, the only way for him to regain them was by another sudden shock.

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    There are many reasons why people can't get a good night's sleep and as with any other health conditions, things are not likely to improve until you find a way to break the cycle.

    These are some of the main factors that need to be addressed.

    Worry and stress

    We have all been kept awake by many factors that cause worry and stress in our lives. Money problems, relationship issues and work stresses can have you sitting up all night. A useful habit is to download your thoughts at the end of the day. Keep a pen and paper next to your bed and before you go to sleep, write down your thought and worries, create a to-do list for the following day or set down solutions and ideas that relate to work.

    Diet and eating patterns

    What and when you eat can have a major impact on your ability to sleep. Eating too late or indulging in a rich or spicy meal can keep you awake. These foods take a long while to digest and the after effects of indigestion and heartburn are not going to set you up well for a good quality sleep.

    A research suggests that both calcium and magnesium may be linked to poor sleep. Even low intakes of magnesium found in green vegetables, beans, nuts and seeds have been shown to make it harder to stay asleep. Calcium is found in dairy foods, soybeans and green vegetables and low levels have also been shown to make it more difficult to nod off.

    Alcohol and caffeine

    Tea, coffee and energy drinks contain caffeine that helps to stimulate the nervous system and make you more alert, which is great if you need a pick-me-up. Dosing up on caffeine during the day can affect your ability to sleep later on in the evening. Try limiting your intake of caffeine to the morning and switch to decaffeinated options such as herbal teas. Alcohol is a double-edged sword when it comes to sleep. While a little may help to induce slumber, even in small amounts it can cause fragmented sleep patterns.

    Bedroom environment

    “Your bedroom should be dark once the lights are switched off because melatonin, a sleep-regulating hormone, is very light-sensitive. Maintaining the right temperature can also help with sleep as a room that is too hot may prevent your core temperature from going down, which is essential for switching on the sleep mechanism within the body.

    Have you ever been to Taiwan, China's biggest island? Do you want to pay a visit there? We'll show you the best of Taiwan is land.

    We hope you've finally made your peace with Pluto being downgraded from a planet to an ice dwarf (冰矮星)，because we have some more jarring news for you : It seems your teachers may have been wrong about the number of continents on the earth, too.

    Earlier this year, scientists published a report in the journal of the Geological Society of America detailing an eighth continent called Zealandia, roughly the size of India and almost completely hid itself under the Pacific Ocean east of Australia. Covering all of New Zealand as well as several nearby islands, Zealandia likely spent the best of its above-water days as part of the supercontinent Gondwana before fragmenting off Australia and Antarctica some 80 million years ago. This lost, underwater continent is just beginning to reveal its secrets, making for one of the most promising scientific discoveries this year.

    While researchers have been aware of the 1. 9 million-square-mile mass for two decades, Zealandia has only recently become the object of serious study since the Geological Society paper argued that it fits all the criteria for a proper continent, including a continental crust (地壳)that's distinctly separate from the seabed in terms of elevation, thickness, and geology. A team of 32 scientists from 12 countries just completed their first visit to six dig sites around Zealandia, where they drilled up more than 8,000 feet of sediment cores (沉积物岩心)that will help explain the lost continent's 80-million-year history.

    Because there is no official body that formally recognizes continents, whether or not Zealandia ends up in future geography textbooks will come down to its acceptance by the scientific community at large, possibly with a little help from travelers like you.

    Dolphins, African gray parrots and some other animals understand the idea of “zero,” but researchers were surprised to find that honeybees also comprehend this abstract concept, considering the insects' tiny brains, according to a new study. Honeybees have fewer than one million neurons (神经元), compared with the 86 billion neurons in humans—and yet, they grasp a concept that humans, by some measures, don't start to understand before preschool.

    The researchers set up two cards, each of which had a set of symbols on them, like triangles or circles. Then, they trained a group of the bees to fly to the card with the lower number of symbols. The bees quickly learned what the humans wanted them to do to get their delicious, sweet rewards. The trained bees were then shown a card that was empty and one that had symbols on it. There is no need for the bees to be trained to fly more often to the empty card—thus showing that they understood that “zero” was a number less than the others.

    Although they flew more often to an empty card than to one that had one symbol on it, it became easier for them to distinguish when the symbols on the card increased in number. For example, they more often flew to the zero when the other card had four symbols than when it had one.

    Perhaps these findings will explain the brain mechanism (机制) behind what allows us to understand the concept of “nothing,” Adrian Dyer, a researcher said. This understanding, in turn, could help in the development of artificial intelligence (AI) that also understands this concept. “If bees can understand 'zero' with a brain of less than a million neurons, it suggests there are simple, efficient ways to teach AI new tricks,” Dyer said in the statement.

Elon Musk is a symbol of passion, hard work and success. A person may work hard in his life, but when hard work goes along with passion and a new idea, then something is created that astonishes the world. As the founder of big companies like PayPal, SpaceX and Tesla Motors, Elon Musk is a guide and inspiration for the youth around the world. 

Elon Musk was born on June 28, 1971 in Pretoria, South Africa. He was the eldest of three children. His father Errol Musk, a British-born South African, was an engineer. Musk spent his childhood in South Africa and at the age of 9, he got his first personal computer. This got Elon interested in programming and he started to learn on his own. At the age of 12, he made his first computer game, Blaster, which earned him $500 when he sold the source code to a magazine. 

When he was 17, he decided to leave home and had wanted to move to the United States after graduating from a secondary school in Pretoria. However, he was unable to move to the United States. In 1989, Elon Musk moved to Canada, where his mother's relatives lived. After obtaining Canadian citizenship, Musk went to Montreal. Due to a lack of money, he found a low-paying job. At the age of 19, he entered Queens University in Kingston, Ontario, studying there for two years. Finally, in 1992, his dream came true—he moved to the United States. 

As a teenager, Musk struggled with depression. But then he realized that the most important thing was presenting himself with the right questions. The day he started doing this, everything started to get easier. 

Musk thought that a human being had to expand the limits of his consciousness—to ask the right questions and get answers to them; thus he asked the best question of all: what will have the greatest impact on the future of humans? Musk found that these things were the Internet and space exploration. 

The life of Elon Musk is inspiring. He found success on the Internet, without much formal learning. By reading books and using his willpower and dedication, he reached a level of knowledge that is difficult to imagine. He did not give up until he achieved his dreams. Elon Musk truly stands out among other billionaires because of his leadership abilities, positive attitude, ability to know when to take risks, and belief in futuristic technologies.