Today, we are told, children don't spend enough time in the fresh air. Many of them are addicted to screen on a computer or a TV—they seem to be living in a virtual world. They have lost touch with nature.

    But now 400 organizations in the UK, from playgroups to the National Health Service, are encouraging children to have some “wild time”. They want kids to swap at least 30 minutes of watching TV or playing computer games for time playing outside. Activities such as building dens, climbing trees, rummaging for conkers and playing hide and seek are just some of the things kids can do. Even if they live in a city, they can go on adventures in the garden or the park.

    Children often need a helping hand from mom and dad. They need to be shown what to do and where to go. Andy Simpson from National Health Service says, “We want parents to see what this magical wonder product does for their kids' development, independence and creativity, by giving wild time a go”.

    So despite the complicated world that young people grow up in now, it seems that going back to basics and experiencing “nature's playground” is what modern children need. David Bond from Project Wild Thing says, “We need to make more space for wild time in children's daily routine, freeing this generation of kids to have the sort of experiences that many of us took for granted”.

    This might sound a bit old fashioned to you or maybe, like me, it's made you think about sticking on your boots, getting outdoors and reliving your childhood. There is no age limit on enjoying yourself!

    There is a breakthrough in building aircrafts. Bendable wings covered with overlapping(部分重叠) pieces resembling fish sizes could be used to build swifter, fuel-efficient aircraft, a new study finds.

    Nowadays, conventional aircrafts typically rely on ailerons (副翼) to help control the way the planes tip as they fly. However, when the Wright brothers flew the first airplane, Flyer 1, over a century ago, they used no ailerons but wires and pulleys that twisted the wood-and-canvas wings, to control the plane.

    Scientists have long sought to develop aircrafts that can alter their wings during flight, just as birds can. However, most previous attempts have failed because they relied on heavy mechanical control structures within the wings. These structures were also complex and unreliable, said Neil Gershenfeld, a physicist and director of the Center for Bits and Atoms at Massachusetts Institute of Technology (MIT).

    The new wing consists of a system of tiny, strong, lightweight modules. The shape of the wing can be changed uniformly along its length using two small motors, which apply a twisting pressure to each wingtip. These wings are covered in “skins” of overlapping strips of flexible material resembling fish sizes. These strips move across each other as the wings alter, providing a smooth outer surface, the researchers explained.

    Wind-tunnel tests of these wings showed that they at least matched the aerodynamic properties of conventional wings, at about one-tenth the weight. Initial tests using remotely piloted aircrafts made with these wings have shown great promise, said Benjamin Jenett, a graduate student at the Center for Bits and Atoms at MIT.

    The new modular structures the scientists developed could be manufactured quickly in mass quantities and then installed by teams of small robots. These modular structures also can be disassembled more easily, making repairs simpler.

    “Still, the first aircraft built using this strategy will not be a passenger jet, ”Gershenfeld said. “Instead, the technology will likely first be tested on unmanned aircraft, leading to drones (无人机) that can fly for a long time, to help deliver internet access or medicine to remote villages and do some rescue works.”

    When I was five or six years old, I remember watching TV and seeing other children suffer in other parts of the world. I would say to myself, "When I grow up, when I can get rich, I will save kids all over the world."

    At 17, I started my career here in America, and by the age of 18, I started my first charity organization. I went on to team up with other organizations in the following years, and met, helped, and even lost some of the most beautiful souls, tern six-year-old Jasmina Anema who passed away in 2010 from leukemia (白血病), whose story inspired thousands to volunteer as donors, to 2012 when grandmother lost her battle with cancer, which is the very reason and the driving force behind the Clara Lionel Foundation( CLF). We're all human. And we all just want a chance: a chance at life, a chance in education, a chance at a future, really. And at CLF, our mission is to impact as many lives as possible, but it starts with just one.

    People make it seem too hard to do charity work. The truth is, you don't have to be rich to help others. You don't need to be famous. You don't even have to be college-educated. But it starts with your neighbor, the person right next to you, the person sitting next to you in class, the kid down the block in your neighborhood. You just do whatever you can to help in any way that you can. And today, I want to challenge each of you to make a commitment to help one person，one organization，one situation that touches your heart. My grandmother always used to say, "If you've got a dollar, there's plenty to share."

    There are many programs for high school students today that help isolated teenagers cope with loneliness. However, loneliness is not only an issue for teens but also an important and rarely acknowledged one in the elderly.

    In Britain, Tracey Crouch was appointed to be the first Minister of Loneliness in order to address the issues caused by loneliness. This is the first time such a position has been created.

    In Britain, there are around 9 million people who say they are lonely frequently. In Germany, a study conducted by Ruhr University Bochum found that 20 percent of people over the age of 85 felt lonely, and 14 percent of those between age 45 and 65 felt socially isolated. In the United States, more than 25 percent of the population lives alone, more than 50 percent are unmarried.

    Isolation is generally associated with cardiovascular disease, depression, obesity, and anxiety. Additionally, the stress from loneliness can cause your cells to change on a molecular(分子)level that reduces its abilities to defend your body against diseases. In fact, doctors believe having feelings of loneliness is equivalent to smoking 15 cigarettes per day in regard to its impact on health!

    In Britain, the new Minister of Loneliness will help establish government policies on the issue and fund charities to devote their efforts towards aiding loneliness. There are charities that link lonely seniors to high school students in order to give them a line of communication whenever they feel lonely!

    The possibilities for the new Minister of Loneliness are endless. For example, she can provide education services to household businesses so that they can identify lonely customers if they see one. Loneliness fits into the category of being a social issue that must be monitored by the entire community in order to help those in need. Hence, government involvement in medical services and care for seniors and others is essential for happy seniors.

    If you ask most people what water tastes like, they'll probably tell you that water has no taste and they may give you a funny look. But if you were a fruit fly, asking another fruit fly, that question might have a different answer.

    To a fruit fly, water has a taste. Scientists want to know how the fruit fly knows water because this information may help in learning how other animals — or even individual cells — manage to use water in the right way. Water is vital to life, but too much or too little can be deadly to a living creature. So by understanding how the fruit fly tastes water, researchers may learn more about other living things.

    According to the new study, a protein(蛋白质) called PPK28 makes it possible for a fly to taste water. Proteins build cells and tissues, fight disease and carry messages between cells. It's not surprising that a protein is responsible for the fruit fly's ability to taste water.

    The PPK28 protein is part of a larger family of similar proteins. One of these related proteins is used by mammals (including humans) to taste salt. Scientists have not found a protein that enables humans to "taste" water.

    In the experiment, Cameron and his team compared normal fruit flies with fruit flies whose taste cells had been disabled. The fruit flies were given a special chemical that would glow(发光) when the fly used the PPK28 protein. Then the scientists led the flies to water. When the normal flies tasted the water, the PPK28 protein lit up — showing that it was in use.

    The fruit fly in particular is so interesting that some scientists are hard at work creating a complete map of the fruit fly brain. This map will show all of a fly's neurons and help scientists understand how the neurons work together.

It's normal to long for the taste of potato chips or a cheese-covered pizza. Even though they're full of calories, eating them occasionally won't do much harm. However, according to the new numbers, young people are becoming more gluttonous. The BBC's Good Food Nation Survey showed that on average, 16 to 20-year-olds ate fast food at least twice a day in the UK. So what's behind this fast food binge (狂热)?

WebMD, an online publisher of news and information of human health and well-being, surveyed nearly 600 teenagers and adults in the United States. They found that the most common reason was our busy lifestyle. More than 92.3 percent of respondents said they were too busy to cook. Many find it challenging to balance work and life, and the convenience of fast food meets their needs. Fast food is readily available in corner stores and vending machines (自动售货机). Remember those instant noodle cups from the supermarket? They're ready in minutes, and you can store them at home for a long time.

But many people think this trend does no good. Sarah Toule, head of health information at World Cancer Research Fund, told the BBC: "It's frightening that people, especially younger generations, are eating so much fast food loaded with fat, sugar and salt, but offers little nutritional value."

She added, "Especially high in calories, fast food leads to unhealthy weight gain — which in turn increases the risk of 11 cancers later in life."

So what is the right thing to do? Toule suggested that young people should prepare meals in advance and learn to include the different food groups in their diets.