Nowadays people are putting our water supply in danger, because they use too much water or throw rubbish into the river. You may wonder how paving(铺砌) a road can lead to less usable fresh water. A major part of thewaterweuse every day is groundwater. Groundwater does not come from lakes or rivers. It comes from underground. The more roads and parking lots we pave，the less water can flow into the ground to become groundwater.

    Human activity is not responsible for all water shortages(短缺). Drier climates are of course more likely to have droughts(干旱) than areas with morerainfall，but in any case, good management can help to make sure there is enough water to meet our basic needs.

    Thinking about the way we use water every day can make a big difference，too. In the United States，a family of four can use 1.5 tons of water a day! This shows how much we depend on water to live，but there's a lot we can do to lower the number.

    You can take steps to save water in your home. To start with，use the same glass for your drinking water all day. Wash it only once a day. Run your dishwasher (洗碗机)only when it is full. Help your parents fix any leaks in your home. You can even help to keep our water supply clean by recycling batteries instead of throwing them away.

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    WeChat is a social mobile application with voice and text messaging timeline and several social features like ‘Message in a Bottle'. WeChat, a popular instant messaging tool run by Tencent Holdings, aims to help users access mobile services without downloading separate apps, which experts said may challenge the business of smartphone app distributors such Apple Store.

This new feature, named ‘Mini Programs', allows WeChat users to find a variety of services such as ticket buying by scanning a QR (quick-response) code, saving them the trouble of installing a number of different apps on smart devices, according to the transcript of a speech by Zhang Xiaolong, Tencent's senior executive vice president, on Wednesday. The new function is expected to come online on January 9.

    Zhang, known as the father of WeChat, emphasized that ‘Min Programs' is not a mobile app distributing function.

    Still, experts and app developers said that the rollout (推出) of ‘Mini Programs' on WeChat will erode the market share of app distributors like Apple Store in China.

     “‘Mini Programs' will attract lots of start-ups, because a program based on WeChat can help them build up businesses at much lower costs,” a Shanghai-based app developer, told the Global Times Wednesday.

    If a start-up wants to promote its business via a separate application, it has to hire a special team to develop two different apps— one each for iOS and Android.

    Lsiunched in 2011, WeChat has evolved to include services such as ‘Order Taxi', ‘Food Delivery', e-commerce and payments from just an instant messaging app.

    Getting paid to stay in bed all day sounds pretty good. But what if someone offered you $23,000 to stay in bed for two months? That's the deal that are search team is offering to 24 volunteers.

    Researchers are looking for volunteers to help them study the influences of weightlessness on the human body by spending 60 days lying down. Lying in bed isn't exactly the same as being weightless, but the influences on the human body are similar.

    When astronauts spend a long time in an environment with no gravity(重力), like the International Space Station (ISS),their bodies are affected in many ways. After a couple of months on the ISS, astronauts' hearts don't beat as hard. Their muscles（肌肉）become weaker because they no longer have to work against gravity. Their bones may break more easily. There may also be changes in the astronauts' sleep habits.

    Dr. Arnaud Beck, the researcher in charge of the study, said his goal is to measure the influences of weightlessness, and also to find ways to prevent problems. The study will take 88 days altogether. During the first two weeks the volunteers will be tested to establish(确定) their levels of fitness. Then they will spend 60 days lying in bed with their heads slightly lower than their bodies. They will have to do everything while lying down, including brushing their teeth and going to the bathroom. Dr. Beck said the rule is that they must have at least one shoulder touching the bed at all times. Half of the volunteers in the study will be taking capsules(胶囊) containing special food supplements（增补物）several times a day to see if they help reduce the health problems caused by weightlessness. The last two weeks of the study will be spent trying to let the volunteers recover. Volunteers must be men between the ages of 20 and 45 who are in perfect health. They must be non-smokers.

    The study will take place from September 1^st to November. The first two days are the time for volunteers to sign in.

My First Marathon（马拉松）

    A month before my first marathon, one of my ankles was injured and this meant not running for two weeks, leaving me only two weeks to train. Yet, I was determined to go ahead.

    I remember back to my 7th year in school. In my first P.E. class, the teacher required us to run laps and then hit a softball. I didn't do either well. He later informed me that I was "not athletic".

    The idea that I was "not athletic" stuck with me for years. When I started running in my 30s, I realized running was a battle against myself, not about competition or whether or not I was athletic. It was all about the battle against my own body and mind. A test of wills!

    The night before my marathon, I dreamt that I couldn't even find the finish line. I woke up sweating and nervous, but ready to prove something to myself.

    Shortly after crossing the start line, my shoe laces(鞋带) became untied. So I stopped to readjust. Not the start I wanted!

    At mile 3, I passed a sign: "GO FOR IT, RUNNERS!"

    By mile 17, I became out of breath and the once injured ankle hurt badly. Despite the pain, I stayed the course walking a bit and then running again.

    By mile 21, I was starving!

    As I approached mile 23, I could see my wife waving a sign. She is my biggest fan. She never minded the alarm clock sounding at 4 a.m. or questioned my expenses on running.

    I was one of the final runners to finish. But I finished! And I got a medal. In fact, I got the same medal as the one that the guy who came in first place had.

    Determined to be myself, move forward, free of shame and worldly labels(世俗标签), I can now call myself a "marathon winner".

    Reading may be fundamental, but how the brain gives meaning to letters on a page has been a mystery. Two new studies fill in some details on how the brains of efficient readers handle words. One of the studies, published in the April 30 Neuron, suggests that a visual-processing area of the brain recognizes common words as whole units. Another study, published online April 27 in PLOSONE, makes it known that the brain operates two fast parallel systems for reading, linking visual recognition of words to speech.

    Maximilian Riesenhuber, a neuroscientist at Georgetown University in Washington, D. C. , wanted to know whether the brain reads words letter by letter or recognizes words as whole objects. He and his colleagues showed sets of real words or nonsense(无意义的词语)words to volunteers undergoing FMRI scans. The words differed in only one letter, such as “farm” and “form” or “soat” and “poat”, or were completely different, such as “farm” and “coat”or “poat” and “hime”.The researchers were particularly interested in what happens in the visual word form area, or VWFA, an area on the left side of the brain just behind the ear that is involved in recognizing words.

    Riesenhuber and his colleagues found that neurons(神经元)in the VWFA respond strongly to changes in real words. Changing “farm” to “form”, for example, produced as great a change in activity as changing “farm” to“coat”, the team reports in Neuron. The area responded slowly to single-letter changes in made-up words.

    The data suggests that readers grasp real words as whole objects, rather than focusing on letters or letter combinations. And as a reader's exposure to a word increases, the brain comes to recognize the shape of the word. “Meaning is passed on after recognition in the brain”, Riesenhuber says.

    The researchers don't yet know how longer and less familiar words are recognized, or if the brain can be trained to recognize nonsense words as a unit.

    Most of us might only begin to think about dinner in the late afternoon: What should I make today? But Jelena Petrovic begins to think about her big meal early each morning. After morning tea, she and her husband, Milan, begin their plans for a traditional Serbian dish. The cooking method they use probably comes from Jelena's mother or grandmother. Each recipe uses local foods found in Serbian markets.

    Milan goes to the market to get the food they need. And the 69-year-old Jelena makes plans for how she will explain the cooking process to her 150, 000 followers on YouTube. Once she is ready, Jelena films her cooking show from a small kitchen table. Milan holds the camera.

    Jelena has many years of cooking experience at home. Ten years ago, she started an online program, where she shared recipes and cooking suggestions for meat, soup, bread, sweet treats and more.

    Her number of followers grew over time. She decided to start a blog and began also making videos she filmed with her mobile phone. Today, her videos on YouTube have over 50 million views. Last year, "Granny's Kitchen" was named one of the Top 50 YouTube channels in Serbia.

    Now her YouTube channel takes up much of her day. She works from her small kitchen and home office. Colorful plants and flowers fill the room. A bright cloth covers the table where she works. She says she gets tired from cooking long hours each day. But, she said, "My viewers wait for a new recipe every morning. If I am late, they will ask if I am well or what is happening."

    Often, her viewers write that the recipes bring back happy memories of their childhood. "My recipes are all local, traditional home-food recipes," Jelena said. "I make things my mother or grandmother used to make."