Conventional wisdom says that hardship can make us old before our time. In fact, a new study suggests that violence not only leaves long-term scars on children's bodies, but also changes their DNA, causing changes that are equal to seven to ten years of premature aging.

    Scientists measured this by studying the ends of children's chromosomes (染色体), called telomeres (端粒), says Idan Shalev, lead author of a study published in Molecular Psychiatry.

    Telomeres are special DNA sequences (序列) which prevent the DNA in chromosomes from separating. They get shorter each time a cell divides, until a cell cannot divide any more and dies.

    Several factors have been found to shorten telomeres, including smoking, radiation and psychological stresses such as being treated badly when young and taking care of a chronically ill person.

    In this study, researchers examined whether exposure to violence could make children's telomeres shorten faster than normal. They interviewed the mothers of 236 children at ages 5, 7 and 10, asking whether the youngsters had been exposed to domestic violence between the mother and her partner; physical maltreatment by an adult; or bullying. Researchers measured the children's telomeres-in cells obtained by wiping the insides of their cheeks-at ages 5 and 10.

    Telomeres shortened faster in kids exposed to two or more types of violence, says Shalev. Unless that pattern changes, the study suggests, these kids could be expected to develop diseases of aging, such as heart attacks or memory loss, seven to 10 years earlier than their peers.

    Shalev says there is hope for these kids. His study found that, in rare cases, telomeres can lengthen. Better nutrition, exercise and stress reduction three things that may be able to lengthen telomeres, he says.

    The study confirms a small but growing number of studies suggesting that early childhood a adversity imprints itself in our chromosomes, says Charles Nelson, a professor of pediatrics and neuroscience at Harvard Medical School.

    Derek Rabclo is not the only surfer to conquer Hawaii' s famous Pipeline big wave break, but while all others use their sight to do it, this young professional surfer must rely only on his other senses. That's because he is completely blind.

    When Derek was born, over 24 years ago, he got his name from Derek Ho, the first Hawaiian surfing world champion. A surfing enthusiast himself, Emesto dreamed that his son would share the talent of his uncle, a professional surfer. Unfortunately, Derek was born completely blind, but this didn't slop his family from believing lhat he could do anything he wanted, even if that meant becoming a surfer.

    At age 2, Derek received a bodyboard and the beaches of Guarapari, Brazil, became his backyard. He was always comfortable in the water and surfing was in his blood, but he didn't actually try riding a wave until he turned 17, when his father bought him a surfboard. His father taught him the basics and encouraged him to keep practicing, but after successfully standing up on the surfboard, Derek knew he needed to become much better if he was going to achieve Emesto's dream and become a professional surfer. So he joined the Praia do Moroo surf school, where he studied under coach Fabio Maru.

    Standing up on a surfboard and conquering small waves is one thing, while gathering the courage to take on Hawaii's board-breaking Pipeline is another. But that's exactly what Derek Rabelo set out to do just months after learning how to surf. Everyone told him it was too dangerous, but he felt he could do it. And he did, earning the praise of famous professional surfers like Kelly Slater and Mick Fanning. Now 24, Rabelo has been surfing the Pipeline every winter since.

    Camping is a good way to spend time along with your kids and to show them how wonderful nature can be. Through camping, children can discover new things about nature, such as flowers, birds, and other small animals. Camping gives kids time to get away from all the electronics (电子) of today's culture. So it is necessary to plan exciting and enjoyable family camping trips with your children while they are young.

    When planning your family camping trip, consider the activities your kids like: games, hiking, swimming, boating, bicycling, etc. Select a camping place that has some of the activities the kids are interested in. Meal planning is an important part of your camping trip. Plan the meals together, and kids love to choose what they want to eat.

    When starting to pack for your trip, let the kids pack their own items (物品) . Each person should have his/her own sleeping bag with a luggage (行李) bag to put it in. Personal items should be packed with their sleeping bags. Encourage the kids to put their items in a certain place and always return it when they have finished using it.

    When you have arrived at your campsite, make all the camping activities a family activity, which will help children to realize how important team-work is. Everyone can have his/her own job sitting up the campsite. Meal time can be a fun time. So let the older ones help with the cooking on your outdoor camping stove while the younger ones get the picnic table ready.

    Some of the world's biggest companies—Apple, Amazon, Facebook—didn't exist 30 years ago. So what firms are we working for in 2050? That's a question put forward by historian Yuval Noah Harari in his new book "21 Lessons for the 21st Century".

    He argues that because technology is changing so fast, it's one of the first times in human history when we don't know what jobs will look like in the coming three decades." So the best bet is to focus on emotional intelligence（EQ）," he said. "Information is the last thing the kids need. They have too much of it."

    In this book, he focuses on the various challenges facing us today. As he writes in the book's introduction: "What are today's greatest challenges? What should we pay attention to? What should we teach our kids?" One area where these questions crop up is artificial intelligence（AI）Harari believes that AI will completely affect the job market for the next generation of workers.

    His first two books—"Sapiens" and "Homo Deus"—became international bestsellers, selling more than 12 million copies worldwide. They were praised by the likes of Mark Zuckerberg, Barack Obama and Bill Gates. Harari's books, about the past and future of humanity, attract a great number of fans. Fellow Israeli, actress Natalie Portman, is a fan. So is American R&B star Janelle Monae.

    As for Bill Gates, he might be Harari's biggest fan. So when the New York Times asked him to review Harari's latest books, he jumped at the opportunity. "All the three books wrestle with some version of the same question: What will give our lives meaning in the decades and centuries ahead?" Gates wrote in his review. "So far, human history has been driven by a desire to live longer, healthier, happier lives. If science is eventually able to give that dream to most people, and large numbers of people no longer need to work, what reason will we have to get up in the morning?"

    Recently a friend of mine asked me whether I'd seen the TV series Cook' Table. Of course, I hadn't because I'm not that into food. But I do get hungry for adventures sometimes, so I decided to watch the show. This is when I was introduced to the cook Francis Mallmann.

    He makes choices; he doesn't plan. When he was young, he looked for mentors (导师) and experiences, not books or paths. He honored his roots but embraced the world and sought things and places he didn't know. He isn't content with just one lifestyle and he doesn't bend to expectations. This made me puzzled because I grew up thinking I had to have a plan and have long-term stability in front of me.

    When I saw Mallmann doing what makes him happy, everything changed. I thought to myself, "That's how we're supposed to live." I felt as if I'd stood up from a comfortable fireplace and the blanket of my life just fell to the ground. I submitted my leave of absence application to my employer less than a month later. I'm now full of excitement. I'm leaving my job and a good salary, and I'm going to do things that feed my soul.

    Michael Kernis and Brian Goldman, psychologists at Clayton State University in Georgia, studied the benefits of authenticity (真实性) and being true to yourself. Some of the benefits of following your inner voice include enjoying a strong sense of purpose in life, greater confidence, healthier relationships and strong skills.

    I might soon be hungrier and poorer than I was before but at least I'll be staying true to who I am and I'll get the true freedom.

On paper, hydrogen (H2) looks like a dream fuel. Coal, oil, and natural gas produce carbon dioxide, which warms the earth when burned, Hydrogen produces pure water. Hydrogen packs more energy into less space than a battery (but certainly less than petrol) . Also, empty tanks (燃料箱) can be refilled with hydrogen much faster than refilling empty batteries with electricity.

While in practice, things are trickier. Storing a meaningful amount of hydrogen gas requires pressing it several hundred-fold. Changing it into the liquid form is another option, but it should be cooled to-253C. Both processes require a heavy and strong tank. While a 700 bar tank is acceptable for a city bus or a truck, adapting it for use in small vehicles is very difficult because the pressure during refilling would be too great.

The solution? Powerpaste.

A German team of researchers, led by Marcus Vogt, have come up with an interesting "powerpaste", which can store hydrogen energy at atmospheric pressure, ready for release when needed. It is so named because it comes in tubes and looks like toothpaste (牙膏) , not in its traditional form of gas.

The main ingredient (原料) of the paste is magnesium hydride, a substance that reacts with water to form hydrogen. The escaped hydrogen can then be directed into a fuel cell, where it reacts with oxygen from the air to produce electric power.

Refueling is very simple, as instead of going to a filling station, drivers and riders can simply replace an empty tube with a new one and refill the water tank.

Given that powerpaste only begins to break down at temperatures of around 250℃ it remains safe even when a vehicle stands in the baking sun for hours.

However, we will have to be patient. Just because researchers have succeeded in developing a new fueling way does not mean that we can expect to see such vehicles on the road anytime soon. It will indeed be several years before this concept is turned into reality.