About 5,000 children die each day due to preventable diseases such as cholera and dysentery (痢疾) , which spread when people use unclean water for drinking or cooking. A lack of water for personal health leads to the spread of totally preventable diseases like trachoma, which has blinded some six million people.

    Water troubles also trap many low-income families in a cycle of poverty and poor education and the poorest suffer most from lack of access to water. People who spend much of their time on ill health, caring for sick children, or collecting water at distances averaging 3.75 miles a day don't have educational and economic opportunities to better their lives.

    Agriculture is called the lion's share of freshwater worldwide, using some 70 percent, and industrial uses consume another 22 percent. Water areas have no political borders and nations don't always work together to share common resources, so water can be a frequent source of international conflict as well.

    Day-by-day demand keeps growing, further needing water sources, from great rivers to groundwater. “We're going deeper into debt on our groundwater use,” Postel said, “and that has very significant impacts on global water security. The rate of groundwater consumption has doubled since 1960.”

    Some of Earth's groundwater is fossil water created when Earth's climate was far different. Today such water is as limited as petrol. “But we're pumping much of them out faster than ever,” Postel explained. “Humanity's growing thirst also causes a major problem about water and our ecosystems. And that also creates a cost to us, to our sons and to our grandsons, not just to nature.”

    Cold weather during winter months may keep many people from leaving home and running in the open air.

    However, a new study shows that the drop in temperature is a good reason to run. In fact, researchers say, running in cold weather helps improve one's performance.

    Many people say running in the winter can be difficult. Two reasons are the low temperatures and bitter winds. Yet many runners might find it easier than running in hot weather.

    That could be because lower temperatures reduce stress on the body. When you run in cold weather, your heart rate and the body's dehydration (脱水) levels are lower than in warmer conditions. The body needs less water on a cold day than in warm weather.

    This information comes from sports scientists at St. Mary's University in London. John Brewer is a professor of applied sport science at St. Mary's.

    For this study, he and other researchers put a group of people into a room they called an "environmental chamber." The researchers then recreated summer and winter weather conditions in the room. The test subjects were asked to run 10,000 meters under both conditions. Brewer says he and his team recorded biological measurements of the runners.

    "We've got a group of subjects into the environmental chamber, we've changed the conditions to replicate the summer or winter and we've got them to run a 10km under both of those conditions and taken various measurements on each runner while they've been completing their 10km."

    Brewer says every movement runners make produces heat. He explains that one way in which we lose heat is by sweating. The body loses heat through droplets of sweat. He says the body also loses heat by transporting the blood to the surface of the skin.

An Invisible Smile

    Mr Dawson was an old man who always complained a lot, and everyone in town knew it. Kids ever went into his yard to pick a delicious apple. Old Dawson, they said, would come after them with his gun.

    One Friday, 12-year-old Janet was going to stay all night with her friend Amy. They had to walk by Dawson's house on the way to Amy's house, but as they got close, Janet saw him sitting on his front porch and suggested they cross over to the other side of the street. Like most of the children，Janet was scared of the old man.

    Amy said not to worry, Mr Dawson wouldn't hurt anyone. Still, Janet was growing more nervous with each step closer to the old man's house. When they got close enough, Dawson looked up with his usual frown, but when he saw it was Amy, a broad smile changed his entire face as he said, “Hello, Miss Amy. I see you've got a little friend with you today. ”

    Amy smiled back and told him Janet was staying overnight and they were going to listen to music and play games. Mr Dawson said that sounded fun and offered them each a fresh picked apple off his tree. They gladly accepted. Mr Dawson had the best apples in the whole town.

    When they left, Janet asked Amy, “Everyone says he's the meanest man in town. How come he was so nice to us?”

    Amy explained that when she first started walking past his house he wasn't very friendly and she was afraid of him, but she pretended he was wearing an invisible smile and so she always smiled back at him. It took a while, but one day he half-smiled back at her.

    After some more time, he started smiling real smiles and then started talking to her. Just a “hello” at first, then more. She said he always offered her an apple and was always very kind.

    “An invisible smile? ”questioned Janet.

    “Yes,”answered Amy, “my grandma told me that if I pretended I wasn't afraid and pretended he was smiling an invisible smile at me and I smiled back at him, sooner or later he would really smile. Grandma says smiles are contagious.”

If we remember what Amy's grandma said — everyone wears an invisible smile, we too will find that we're always on the go trying to accomplish so much, aren't we? It's so easy to get caught up in everyday life that we forget how simple it can be to bring cheer to ourselves and others. Giving a smile away takes so little effort and time. Let's make sure that we're not the ones that others have to pretend to be wearing an invisible smile.

    I'm sitting in my kitchen in London, trying to figure out a text message from my brother. He lives in our home country of Germany. We speak German to each other, a language that's rich in odd words, but I've never heard this one before: fremdschämen. I'm too proud to ask him what it means. I know that eventually, I'll get it. Still, it's slightly painful to realize that after years of living abroad, my mother tongue can sometimes feel foreign.

    Most long-term migrants know what it's like to be a slightly rusty(生疏的) native speaker. The process seems obvious: the longer you are away, the more your language suffers. But it's not quite so straightforward.

    In fact, the science of why, when and how we lose our own language is complex and often different to what we think. It turns out that how long you've been away doesn't always matter. Socializing with other native speakers abroad can worsen your own native skills. And emotional factors like trauma(精神创伤) can be the biggest factor of all.

    It's not just long-term migrants who are affected, but to some extent anyone who picks up a second language. The minute you start learning another language, the two systems start to compete with each other, says Monika Schmid, a linguist at the University of Essex.

    Schmid is a leading researcher of language attrition, a growing field of research that looks at what makes us lose our mother tongue. In children, the phenomenon is somewhat easier to explain since their brains are generally more flexible and adaptable. Until the age of about 12, a person's language skills are relatively easy to change. Studies on international adoptees have found that even nine-year-olds can almost completely forget their first language when they are removed from their country of birth.

    But in adults, the first language is unlikely to disappear entirely except in extreme circumstances. For example, Schmid analyzed the German of elderly German-Jewish wartime refugees(难民) in the UK and the US. The main factor that influenced their language skills wasn't how long they had been abroad or how old they were when they left. It was how much trauma they had experienced as victims. Those who left Germany in the early days of Nazi occupation, before the worst violence, tended to speak better German – despite having been abroad the longest. Those who left later, tended to speak German with difficulty or not at all.

    "It seemed very clearly a result of this trauma", says Schmid. "Even though German was the language of childhood, home and family, it was also the language of painful memories." The most traumatised refugees had held them back. As one of them said: I feel that Germany betrayed me. America is my country, and English is my language.

Hot Spots for Retirees to Start Their Encore Career

    Encore Career: Vocational School Instructor

    Retire in: Los Angeles, CA

    Ever since IBM CEO Ginni Rometty coined the term "new collar" to describe well-paid jobs that require specific skills but not necessarily a degree, vocational schools have made a serious comeback. Apparently instructors are in short supply in sunny L.A., where there are 13 jobs at vocational schools for every applicant on the market. This is a great opportunity for skilled retirees since, unlike teaching at a public school that requires a state certificate, the only requirement here is that you be a seasoned expert in your field.

    Encore Career: Business Consultant

    Retire in: Miami, FL

    Consulting is a great option for a retired business professional looking to make their own hours, be their own boss, and earn as much or as little as needed to maintain their standard of living. For every consultant in Miami right now there are 13 businesses hoping to hire them. There's even greater demand here than in Washington D.C., which is typically considered the consulting capital of the world.

    Encore Career: Tourist Wrangler

    Retire in: Austin, TX

    As the economy continues to boom and more Americans have extra income to spend, the tourism industry has taken off. This is particularly true in Austin, TX, where there were astonishing 36 tourism jobs for every applicant in July. Between four-star hotels, the noisy rock n' roll scene, and a new food culture, Austin is the place to be if you want to work in service industry.

    Encore Career: Supporter of the Arts

    Retire in: Charleston, SC

    If you're a Baby Boomer with a degree in the arts, now could be the perfect time to revisit your passion for creativity, especially if you also want to live in the center of southern charm. Between the 14 art galleries on King Street in Old Town, an abundance of acting companies and theaters, and music festivals, it's not surprising there were 25 jobs for every arty applicant iii Charleston.

    Does your older brother think he's cleverer than you? Well, he's probably right. According to a new research published in the journal Intelligence, the oldest children in families are likely to have the highest IQs and the youngest the lowest.

    A number of studies have suggested that IQ scores decline with birth order. In the most recent study, at Vrije University, Amsterdam, researchers looked at men and women whose IQ had been tested at the ages of 5, 12, and 18.

    The results, which show a trend for the oldest to score better than the youngest in each test, involved about 200,000 people. That showed that first-borns had a three-point IQ advantage over the second-born, who was a point ahead of the next in line.

    The order of birth can also affect personality, achievement, and career, with first-borns being more academically successful and more likely to win Nobel prizes. However, eldest children are less likely to be radical(不同凡响的) and pioneering. Charles Darwin, for example, was the fifth child of six.

    Exactly why there should be such differences is not clear, and there are a number of theories on environmental influences on the child.

    The so-called dilution(稀释法) theory suggests that as family resources, both emotional and physical, as well as economic, are limited, it follows that, as a result , as more children come along, the levels of parental attention and encouragement will drop. Another theory is that the intellectual environment in the family favors the first-born who has, at least for some time, the benefit of individual care and help.

    The theory which enjoys the most support is that the extra time and patience that the earlier-borned get from their parents, compared with those arriving later, gives them an advantage.