Sometimes, you just can't help it. Maybe you're watching a sad movie, or thinking about the friend who moved away. Next thing you know, your eyes are watering, and you havetears running down your cheeks. Why do peoplecry when they are emotional? What are tears? Scientists are working hard to find the answers to these questions.

    Ad Vingerhoets is a professor of psychology at Tilburg University, in the Netherlands. He is one ofthe few scientists in the world who have studied crying. According to Vingerhoets, there are three types of tears. Basal tearsare the first type. Theylubricate(润滑) the eyes andact as a protective barrier between the eye and the rest of the World. Next arereflex tears. They wash youreyes clean when something gets in them. Finally, there are emotional tears. “These are released in response to emotional states, ”explains Vingerhoets. “Especially when we feel helpless.”

    Scientists believe that crying has something to do with how humans developed and learned to depend on each other.“Humans are very complex social creatures,”says Lauren Bylsma, a professor at the University of Pittsburgh, in Pennsylvania.“It seems that tears serve to arouse help and support from others," She says. “Another reason we weep is that humans have the longest developmental period of almost any animal. It takes along time to grow up. ”

    Vingerhoets agrees. “I think that the reason why humans shed tears(流眼泪) has somethingto do with our childhood,”he says. “That's the time when we are stir dependent on adults for love and protection and care. The major advantage of emotional tears is that you can target them at a specific person.”Vingerhoets says this ability to target someone could have come in hand in prehistorictimes, when humans were living among dangerous animals. Crying couldattract predators(捕食者). Tears were asafer way to get attention. In this case, it is better to use a silent signal to ask for help,”he says.

    Vingerhoets and Bylsma do frequent studies to better understand why humans cry. According to Byhma, there is still much more to discover. “It's surprising,”she says,“how much we still don't know.”

    Many facts suggest that children are overweight (超重的) and the situation is getting worse, according to the doctors. I feel there are a number of reasons for this.

    Some people blame the fact that we are surrounded by shops selling unhealthy, fatty foods, such as fried chicken and ice cream, at low prices. This has turned out a whole generation of grown-ups who seldom cook a meal for themselves. If there were fewer of these restaurants, then probably children would buy less take-away food.

    There is another argument that blames parents for allowing their children to become overweight. I agree with this, because good eating habits begin early in life, long before children start to visit fast food shops. If children are given fried chicken and chocolate rather than healthy food, or are always allowed to choose what they eat, they will go for sweet and salty foods every time, and this will carry on throughout their lives.

    There is a third reason for this situation. Children these days take very little exercise. They do not walk to school. When they get home, they sit in front of the television or their computers and play computer games. Not only is this an unhealthy pastime (消遣), it also gives them time to eat more unhealthy food. What they need is to go outside and play active games or sports.

    The above are the main reasons for this problem, and therefore we have to encourage young people to be more active, as well as steering them away from fast food shops and bad eating habits.

    Not long ago, I tried convincing my three daughters that the world's secrets are hidden inside silence. The girls looked at me skeptically. Surely silence is nothing?

    Sitting there at the dinner table, I suddenly remembered their curiosity as children, their wondering about what might be hiding behind a door and their amazement as they stared at a light switch and asked me to “open the light”. But now they are 13, 16 and 19 and wonder less and less. If they still wonder at anything, they quickly pull out their smart phones to find the answer. None of them have any interest in discussing with me. To attract their attention, I told them about two friends of mine who had decided to climb Mount Qomolangma.

    Early one morning they left base camp to climb the south-west wall of the mountain. It was going well. Both reached the summit, but then came the storm. They soon realized they would not make it down alive. The first got hold of his pregnant wife by satellite phone. Together they decided on the name of the child that she was carrying. Then he quietly passed away just below the summit. My other friend was not able to contact anyone before he died. No one knows exactly what happened on the mountain in those hours. Thanks to the dry, cool climate 8km above sea level, they have both been freeze-dried. They lie there in silence, looking no different.

    The girls remained quiet, listening. It seemed as though they had got something.

    It is easy to assume that the essence (本质) of technology is technology itself, but that is wrong. The essence is the time we spend with our family and how much freedom we have by technology.

    While the U.S. is still debating about getting rid of the penny, Sweden is rapidly moving towards abolishing currency (货币) altogether. Though this may sound radical(过激的), it is a natural evolution in this digital society.

    Sweden, which was the first European country to introduce banknotes in 1661, has just been working harder to convince its residents that digital payments are a safer alternative to carrying cash.

    Over the years, the idea has gained popularity with residents, especially the younger generation that is much more comfortable with technology. Today many banks don't even have ATMs and some have stopped handling cash altogether!

    Tickets to ride public buses in most Swedish cities can only be purchased via cell phones. Numerous businesses are also moving towards accepting only digital payments. Even the homeless that sell street paper to make ends meet have to start accepting this mode of payment!

    But despite its growing popularity, some people don't like this radical idea. They include the homeless, elderly people as well as those living in rural areas who are still uncomfortable with mobile phones and computers. But the officials are confident that in the very near future, they will be able to convince everyone to move this safe and more cost-effective payment system.

    Sweden is not the only country trying to abolish paper currency and coins. The movement is rapidly gaining ground in Denmark and Finland as well. In 2014, Israel announced a three-step plan to go cashless and just last week the vendors(小贩)of a popular street in Sydney declared they would stop accepting currency from customers. Whether this phenomenon spreads remains to be seen. But one thing is for sure—With increasingly advanced payment systems being introduced every day, pulling out cash is rapidly becoming "uncool".

    Where to Drink

    Cafe San Bernardo

    Join table-tennis and pool-playing port. Cafe San Bernardo has been running since 1912.The Villa Crespo dive bar also offers up table football for￡4 an hour. Service is efficient; with last orders at 5 am. The daily happy hour between 6 pm and 9 pm includes 60 minutes playing your game of choice, plus a half-bottle of red wine and a corn pie, for￡9.

    Avenue Corrientes 5436, Villa Crespo, 54 11 4805 3956, cafesanbernardo.com

M Salumeria & Enoteca

    Trading only in wine with a story, sommelier(侍酒师)Mariana Torta chooses new ways on a daily basis, and keeps a list of around 250 labels. There's no wine menu—simply take your bottle from the shelf.

    Open 11:00 am-11:30 pm, El Salvador 5777, Palermo Hollywood, 54 11 4778 9016, on Facebook

    Negro Cueva de Cafe

    Coffee has found its place in Buenos Aires. While LAB: Tostadores, The Shelter and Coffee Town are famous new places, Negro Cueva de Cafe is one of the best downtown. It serves Ecuadorian, Colombian and Brazilian beans, and its attracting cakes include croissant.

    Open 9:30 am-7:00 pm, Suipacha 637, Microcentro, 54 11 4322 3000, negrocafe .com

    La Calle

    Head to the Niceto Vega address and you'll be faced with a pizza. Order the special wine, special candy, and prepare to sing until dawn with a high-energy young crowd.

    Open 8:00 pm-2:00 am, Niceto Vega 4942, Palermo Soho, 54 11 3914 1972, on Facebook

    Do you want to help others in Canada or out of the country? Here are some non-profit organizations in Calgary, Canada, through which you can do something for others.

    Calgary Reads

    Calgary Reads helps struggling readers in Grade One and Two twice a week. Trained adult volunteers carry out one-to-one reading teaching in the children's school during school hours. Volunteers are trained to use a proven effective lesson framework. Time is spent coaching readers while providing a strong role model in each child's life.

    Address: 105, 12th Ave SE | Calgary, AB | T2G 2H8

    Telephone: 1 403 777-8254

    Ukrainian Mission Canada

    This organization helps children in need in Ukraine, a country in eastern Europe. You can donate money or things to help one of the children in need.

    Address: 3806 44 Ave NE | Calgary, Alberta | T1Y5V8

    Telephone: 1 403 451-6991

    Calgary Doula Association

    This organization is formed to provide information about services related to birth and child care for the general public and worried professionals. Monthly meetings provide a networking opportunity and exchange of information for individuals interested in birth and child care, couples who are to be parents, and health care providers.

    Address: 124 Crest haven Place SW I Calgary, ABI T3B 5W4

    Telephone: 1 403 750-2033

    Rainbow Society of Alberta

    Rainbow Society of Alberta helps to fulfill wishes of Alberta children with long-term or life-threatening illnesses. Founded in Winnipeg in 1983, Rainbow Society was the first children's organization of its kind in Canada. Its Alberta chapter(分部) was created in 1986 by a handful of caring volunteers who saw need to bring such a strong support system to children in Alberta.

    Address: PO Box 1153, Station M I Calgary, AB

    Telephone: 1 403 252-3891