Dujiangyan is the oldest man-made water system in the world, and a wonder in the development of Chinese science. Built over 2,200 years ago in what is now Sichuan Province in Southwest China, this amazing engineering achievement is still used today to irrigate over 6,000 square kilometres of farmland, take away floodwater and provide water for 50 cities in the province.

    In ancient times, the region in which Dujiangyan now stands suffered from regular floods caused by overflow from the Minjiang River. To help the victims of the flooding, Li Bing, the region governor, together with his son, decided to find a solution. They studied the problem and discovered that the river most often overflowed when winter snow at the top of the nearby Mount Yulei began to melt as the weather warmed.

    The simplest fix was to build a dam, but this would have ruined the Minjiang River. So instead Li designed a series of channels built at different levels along Mount Yulei that would take away the floodwater while leaving the river flowing naturally. Better still, the extra water could be directed to the dry Chengdu Plain, making it suitable for farming.

    Cutting the channels through the hard rock of Mount Yulei was a remarkable accomplishment as it was done long before the invention gunpowder and explosives. Li Bing found another solution. He used a combination of fire and water to heat and cool the rocks until they cracked and could be removed. After eight years of work, the 20-metre-wide canals had been carved through the mountain.

    Once the system was finished, no more floods occurred and the people were able to live peacefully and affluently. Today, Dujiangyan is admired by scientists from around the world because of one feature. Unlike modern dams where the water is blocked with a huge wall, Dujiangyan still lets water flow through the Minjiang River naturally, enabling ecosystems and fish populations to exist in harmony.

    A machine that takes sweat-laden (浸满汗水的) clothes and turns the sweat into drinking water is in use in Sweden. The machine makes the clothes turn round quickly, heats them to remove the sweat, and then passes the steam through a kind of special material to make purified water.

    Since it has been brought into use, its creators say more than 1000 people have drunk others' “sweat” in Gothenburg. They add the liquid is cleaner than local tap water.

    The device was built for the United Nations' child-focused charity UNICEF to promote a campaign highlighting the fact that 780 million people in the world lack access to clean water.

    The machine was designed and built by the engineer Andreas Hammar, known locally for his appearances on TV tech show “Mekatronik”. He said the key part of the sweat machine was a new water purification part developed by a company named HVR.

    “It uses a technique called membrane distillation (膜蒸馏),” he told the BBC. “We use a special kind of material that only lets steam through but keeps bacteria, salts, clothing fibers and other things out. They have something similar to the International Space Station, but our machine is cheaper to build. The amount of water it produces depends on how sweaty the person is, but one person's T-shirt typically produces 10ml, about a mouthful.”

    The device has been put on show at the Gothia Cup-the world's largest international youth football tournament. Mattias Ronge, chief executive of Stockholm-based advertising agency Deportivo, said the machine had helped raise awareness for UNICEF, but in reality had its limitations.

    “People haven't produced as much sweat as we hoped – right now the weather in Gothenburg is lousy,” Mattias Ronge said. “So we've equipped the machine with exercise bikes and volunteers are cycling like crazy. Even so, the demand for sweat is greater than the supply. And the machine will never be produced in large numbers, since there are better solutions out there such as water purifying pills.”

    We all know that exercise is good for your health. But some kinds of exercise may be better than others.

    Running, for example, may help to protect against heart disease and other health problems. Running may also help you live longer. Researchers say it is not important how far you run. It also does not matter how fast or even how often you run. As advertisements for the running shoes Nike say, “Just Do It.”

    Recently researchers studied more than 55,000 adults. About one-fourth of the adults reported running regularly. The study found these runners were considerably less likely than non-runners to die of any form of disease, including heart disease. In fact, the runners lived, on average, three years longer than the non-runners.

    This study lasted 15 years. During that time, more than 3,400 of the individuals died. About 1.200 of the deaths were linked to heart disease, hear, attack or stroke.

    One of the researchers is a man named D.C. Lee, a professor of Iowa State University Compared to non-runners, he said, runners showed a much lower risk of dying from some diseases. “Compared to non-runners, runners showed 30 percent lower risk of death by any causes, including heart attack, stroke and cancer. Also, runners compared to non-runners showed 45 percent lower risk of death by cardiovascular diseases（心血管疾病）, including heart attack and stroke.”

    D. C. Lee and the other researchers found that speed, distance and how often one runs made little difference in reducing the risk of death. The runners in the study averaged between 10 and 16 kilometers per hour. Mr Lee said slower runners and those who only ran once or twice a week were helped nearly as much as those who ran faster and further. “And also we looked at the inning over time and we found that persistent runners（over six years）showed the biggest benefits, as well.”

    Alibaba, Bank of China and Huawei—these are the dream employers for Chinese students, according to a new survey.

    “The survey of more than 55,000 students, conducted by the research firm Universum, has found that roughly a quarter want to work for an international company, while only 9％ want to work for a start-up. Five percent want to start their own business.”

    The students said that work-1ife balance was the most important career goal, followed by job stability. When it comes to desirable companies, Bank of China has been named the top choice by business students for seven consecutive years, and the gigantic state-owned firm shows no signs of giving up its lead.

    William Wu, the China country manager for Universum, said that banking remains an attractive industry for young Chinese. “China's government is now emphasizing the revolution of the finance industry, which leaves the younger generation with the impression that although banking is a traditional industry, there are still a lot of development opportunities.” Wu said.

    E-commerce giant Alibaba (BABA, Tech30) improved six places from 2014, ranking second among business students. Alibaba's rise shouldn't come as much of a surprise—the company held a record-breaking $25 billion IPO in September.

    Among engineering students, Alibaba was once again a bridesmaid. Instead, Huawei—a telecoms infrastructure firm that now makes consumer products-took the top spot.

    “Both of these companies are pioneers in terms of local companies going international.” said Wu. “It shows that… an international development strategy has a positive influence among Chinese young talents.” Tech companies ruled the rankings for humanities students, with Alibaba—which was ninth in 2014 —landing at the top. Last year, Apple was the Number l choice of Chinese students.

    My children are perfect. All four of them. Perfect and beautiful and clever. I bet yours are, too. Except, of course, they are not. In reality, my children and yours are likely to be reasonably average in terms of looks, behavior, intelligence and charm. That's why it is called average. Your belief in your child being special is more probably a biological thing than a fact.

    A loved one, particularly a loved child, is edited as we observe them. Other people's children are spoiled; ours are spirited. Theirs are naughty; ours are confident.

    This is all natural and even touching when not taken too far. However, it is one thing feeding this idea to ourselves but feeding it to our children may be a little less desirable. We have the idea that — unlike my parents' generation — we should build our children's self-respect as high as we can. Therefore, their random scribble (胡写乱画) is up there with Picasso, their C-minus is an unfortunate oversight on the part of the teacher, and the fact that no one wants to be friends with them is because they are particularly clever or sensitive.

    Children see through this kind of thing very quickly and ignore their parents' praises as a matter of course. As they grow up, they sense that the wider world judges them differently. This leads to a – hopefully gentle – cynicism (猜忌) about anything their parents tell them about their achievements. Perhaps that is OK — but I'm not sure if it is good for them to have the parental praise so overlooked.

    If parents were a little harsher sometimes, this could have two positive effects — first, when praise came, it would be more likely to be believed and, second, it would fit in rather more accurately with the picture of reality that the child is forming in their heads.

    A lot of pressure is put on children who are told they are beautiful, special and perfect. Because then, where is there to go? Only downwards. They become too much aware of their status in your eyes, and a danger must be that they fear failing you. To be over-praised by your parents is the counter side of being criticized all the time. Both can have negative consequences.

    It is important to give your children the freedom to be flawed (缺点) — to know that it's OK to be imperfect, and that, in fact, we often love people for their flaws — perfect people (whom we can only imagine, as they do not exist) are easy to respect, but hard to love.

    Now I am nearly 60, my main insight is that I am much less special than I once believed. This knowledge has actually been helpful in leading a more well-balanced life.

    I certainly wouldn't like to go back to attitudes that my parents, particularly my father, held, that to praise the child was to "spoil them" or make them bigheaded. However, the history of families is like the history of everything else — the story of overreactions. We praise our children to the skies, partly because we think it makes them feel good, but also because it makes us feel good. And perhaps it is more the latter than the former.

    Too much love can be as big a burden as a shortage of it. My advice is to limit your praise. Then every piece of praise will count, rather than being just ignored.

    Years ago parents worried their children would learn the truth about Santa Claus(圣诞老人)from others, but now they have a new problem—the Internet.

    A recent study from Hide My Ass! Shows 1 in 8 American parents said the Internet told their children the truth about Santa Claus. 44% of parents thought Google was a danger to this Christmas story, as children searched for Santa and found pages explaining he is not real. About 34 percent of children questioned Santa Claus after seeing ads online for gifts they had asked for in their letters to the North Pole (北极). Sadly，one in three children said their Christmas spirit was dead after reading a post saying Santa wasn't real.

    Before the Internet, the only way children found out their parents bought their gifts was if they were in a bad hiding place. Today, two-thirds of parents never clear their browser (浏览器) history, making it easy for kids to find out the gifts under the tree weren't put there by a happy man and his little helpers.

    To keep Mr. Claus alive, “Keep Believing in Santa”, an organization created by Hide My Ass!, helps kids believe in Santa. Parents receive free software from the organization that monitors all online search results and web pages that could tell kids the truth about the man who lives in the North Pole, by hiding any information that may suggest he doesn't exist.

    However, there is still a higher possibility of the Internet now being the main cause of a child's belief in Santa ending, and it can also result in kids finding out sooner than for those born before the digital age.

    ''With this organization, we wanted to give parents a new tool that would allow them to keep the magic of Christmas and the mystery of Santa for that little bit longer,” Cian  Mckenna-Charley, marketing director at Hide My Ass!.