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    A buld-it-yourself solar still（蒸馏器） is one of the best ways to obtain drinking water in areas where the liquid is not readily available. Developed by two doctors in the U.S. Department of Agriculture, it's an excellent water collector. Unfortunately, you must carry the necessary equipment with you, since it's all but impossible to find natural substitutes. The only components required, though, are a 5'  5' sheet of clear or slightly milky plastic, six feet of plastic tube, and a container— perhaps just a drinking cup — to catch the water. These pieces can be folded into a neat little pack and fastened on your belt.

    To construct a working still, use a sharp stick or rock to dig a hole four feet across and three feet deep. Try to make the hole in a damp area to increase the water catcher's  productivity. Place your cup in the deepest part of the hole. Then lay the tube in place so that one end rests all the way in the cup and the rest of the line runs up — and out — the side of the hole.

    Next, cover the hole with the plastic sheet, securing the edges of the plastic with dirt and weighting the sheet's center down with a rock. The plastic should now form a cone(圆锥体) with 45-degree-angled sides. The low point of the sheet must be centered directly over, and no more than three inches above, the cup.

    The solar still works by creating a greenhouse under the plastic. Ground water evaporates (蒸发) and collects on the sheet until small drops of water form, run down the material and fall off into the cup. When the container is full, you can suck the refreshment out through the tube, and won't have to break down the still every time you need a drink.

    The Asian elephant has been respected for centuries and is still used today for ceremonies and religious purposes. It is respected, not only because it plays a role in Asian culture and religion, but also because it is a key biological species in the tropical forests of Asia.

    The Asian elephant is the largest land mammal in Asian. It is smaller than the African elephant, with relatively smaller ears. Asian elephants have a single “finger” on the upper lip of the long trunk, while African elephants have a second on the lower tip. A number of adult male Asian elephants have no tooth, and the percentage of males carrying ivory(象牙）is different from only about 5% in Sri Lanka to 90% in south India. Asian elephants keep their ears in constant motion in order to free the heat they produce. The species is reported to have well-developed hearing, vision, and smell , and they are also fine swimmers.

    Asian elephants prefer to convey something to form groups surrounding 6 to 7 related females that are led by the oldest female. Like African elephants, these groups occasionally join others to form herds, although these associations are relatively temporary.

    More than two thirds of the day may be spent feeding on grasses, but large amounts of tree bark, roots, leaves and small stems are also eaten. Crops such as bananas, rice and sugar plants are favored foods. Besides, they need to drink at least twice a day so the source of water is quite important.

    The Asian elephant used to live from modern Irap and Syria to the Yellow River in China at first, but it is now found only from India to Vietnam, with a tiny population in the extreme southwest of China's Yunnan Province. More than 100,000 Asian elephants may have existed at the start of the 20^th century. The population is estimated to have fallen by at least 50% over the last 60-75 years.

    We all know what a brain is. A doctor will tell you that the brain is the organ of the body in the head. It controls our body's functions, movements, emotions and thoughts. But a brain can mean so much more.

    A brain can also simply be a smart person. If a person is called brainy, he is smart and intelligent. If a family has many children but one of them is super smart, you could say, “He's the brains in the family.” And if you are the brains behind something, you are responsible for developing or organizing something. For example, Bill Gates is the brains behind Microsoft.

    Brain trust is a group of experts who give advice. Word experts say the phrase “brain trust” became popular when Franklin D. Roosevelt first ran for president in 1932. Several professors gave him advice on social and political issues（问题）facing the U.S. These professors were called his “brain trust”.

    These ways we use the word “brain” all make sense. But other ways we use the word are not so easy to understand. For example, to understand the next brain expression, you first need to know the word “drain”. As a verb, to drain means to remove something by letting it flew away. So a brain drain may sound like a disease where the brain flows out the ears. But, brain drain is when a country's most educated people leave their countries to live in another. The brains are, sort of, draining out of the country.

    However, if people are responsible for a great idea, you could say they brainstormed it. Here, brainstorm is not an act of weather. It is a process of thinking creatively about a complex topic. For example, business leaders may use brainstorming to create new products, and government leaders may brainstorm to solve problems.

    If people are brainwashed, it does not mean their brains are nice and clean. To brainwash means to make some accept new beliefs by using repeated pressure in a forceful or tricky way. Keep in mind that brainwash is never used in a positive way.

    Humans and gorillas shared evolution for 23 million years. Their paths separated only six million years ago. Research on how gorillas communicate can help us understand human language development.

    Understanding how the brain works helps us see a connection between language development and non-verbal signs. These signs or movements include things like the way we move our hands or bodies or the different expressions our faces have in different social situations. A new study on gorillas showed that the right side of the body is controlled by the left part of the brain and it is also the location for language development.

    Two cameras were used to film all of one ape's movements. One of the first results was that gorillas use their right hands more when they are doing actions with their heads or mouths at the same time. This shows that there is a connection between how our brain works and the reason we use one side of our body more than the other. In addition, we can use the results of the study and our knowledge about brains to help us understand more about how language first developed in humans.

    Dr Forrester, who did the study, says the results can be useful in other ways, such as understanding language development in children. For example, some children have serious illness called “autism” which can stop them communicating normally with people. It might be possible to use the same study method to find out which children have this illness when they are very young. Doctors will then be able to start treatment early.

    Stephen Hawking, the brilliant British theoretical physicist who published wildly popular books exploring the mysteries of the universe, has died, according to a family spokesman. He was 76.

    Considered by many to be the world's greatest living scientist, Hawking was also a cosmologist, astronomer, mathematician and author of numerous books including the landmark“A Brief History of Time,” which has sold more than 10 million copies.

    With fellow physicist Roger Penrose, Hawking combined Einstein's theory of relativity with quantum theory(量子理论) to suggest that space and time would begin with the Big Bang and end in black holes. He also discovered that black holes were not completely black but emit(释放) radiation and would likely eventually evaporate(蒸发) and disappear. “It will be difficult enough to avoid disasters on planet Earth in the next 100 years, let alone next thousand, or million. The human race shouldn't have all its eggs in one basket or on one plant. Let's hope we can avoid dropping the basket until we have spread the load.”

    Hawking suffered from ALS (amyotrophic latcral sclerosis), a disease which is usually fatal within a few years. He was diagnosed in 1963, when he was 21, and doctors initially gave him only a few years to live. The disease left Hawking wheelchair-bound and paralyzed. He was able to move only a few fingers on one hand and was completely dependent on others or on technology for everything—bathing, dressing, eating, even speech. “I have been lucky that my condition has progressed more slowly than is often the case. But it shows that one need not lose hope.” Dramatically, he even guest-starred in the “Star Trek”, “The Simpsons” and the 2014movie “The theory of Everything”.

    Hawking leaves behind three children and three grandchildren. “We are deeply saddened that our beloved father passed away today,” Hawking's children, Lucy, Robert and Tim, said in a statement. “He was a great scientist and an extraordinary man whose work and legacy will live on for many years. His courage and persistence with his brilliance and humor inspired people across the world. “We will miss him forever.”

    You know eating fruit and vegetables is helpful. But did you know it can also make you look good?

    People who increased their intake over just six weeks developed a healthy glow and appeared more attractive, researchers found.

    Scientists at St Andrews University found eating them subtly increased yellow and red pigments in the volunteers' skin.

    They monitored the food intake of 35 people and took pictures of their faces, arms and hands using a sensitive camera at the start, and after three and six weeks.

    Increasing their intake of greens by 2.9 portions a day was found to make the person look healthier and an extra 3.3 portion could enhance their attractiveness, when their photographs were rated by others.

    Fruit and vegetables are rich in carotenoids（类胡萝卜素）, which are known to protect against cell damage from pollution and UV rays, and can also prevent age-related diseases including heart disease and cancer.

    But while it was known eating extreme amounts of certain vegetables such as carrots could turn skin orange, it was not known a small increase was perceptible to others and was seen as appealing.

    A camera measured changes to the skin's redness, yellowness and lightness, and found it significantly changed in people who naturally increased their intake. These changes were not evident at three weeks.

    Using light sensors, the researchers showed these red and yellow hues(色调，色相) were linked with the levels of carotenoids in their skin.

    There are hundreds of carotenoids but those thought to have the most dramatic effect are lycopene（番茄红素）which gives tomatoes and red peppers their red color - and beta-carotene found in carrots as well as broccoli, squash, and spinach.

    Skin color is also affected by chemicals called polyphenols(多酚), found in apples, blueberries and cherries, which cause blood rush to the skin surface.