Ever wonder how much a cloud weighs? What about a hurricane? A meteorologist（气象学家） has done some estimates and the results might surprise you.

    Let's start with a very simple white puffy cloud—a cumulus cloud(积云). How much does the water in a cumulus cloud weigh? Peggy LeMone, senior scientist at the National Center for Atmospheric Research in Boulder, Colorado, did the numbers. “The water in the little cloud weighs about 550 tons,” she calculates. “Or if you want to convert it to something that might be a little more meaningful...think of elephants.” Assume（假设） an elephant weighs about six tons, she says, that would mean the water inside a typical cumulus cloud would weigh about one hundred elephants.

    The thought of a hundred elephants' worth of water floating in the sky begs another question—what keeps it up there?

    “First of all, the water isn't in elephant-sized particles(微粒); it's in tiny tiny tiny particles,” explains LeMone. And those particles float on the warmer air that's rising below. But still, the concept of so much water floating in the sky was surprising even to a meteorologist like LeMone. “I had no idea how much a cloud would weigh, actually, when I started the calculations（计算）,” she says.

    So how many elephant units of water are inside a big storm cloud—10 times bigger all the way around than the “puffy” cumulus cloud? Again, LeMone did the numbers: About 200,000 elephants.

    Now, come to the calculations for a hurricane about the size of Missouri and the figures get really massive. “What we're doing is weighing the water in one cubic meter theoretically pulled from a cloud and then multiplying by the number of meters in a whole hurricane,” she explains.

    The result? Forty million elephants. That means the water in one hurricane weighs more than all the elephants on the planet. Perhaps even more than all the elephants that have ever lived on the planet.

    “The failure to play is now a serious issue and it calls for action for change,” says Sir Ken Robinson, a leading expert in education, creativity and human development. This is the driving force behind Outdoor Classroom Day—a global teacher-led campaign, supported by Dirt is Good, a company producing daily chemical products.

    Outdoor Classroom Day, taking place on 17th May and 1st November this year, will see schools around the world swap the inside for the outside and take learning into the playground and beyond to make playtime a key part of the school day. This might involve using natural objects like stones to do sums, or going on an insect hunt to encourage curiosity. By now, Outdoor Classroom Day has grown from a grassroots movement to a global campaign that is expected to benefit five million children and over 40,000 schools from all around the world in 2018.

    This is helping to change the trend that sees many schools selling up or building on their playgrounds and cutting back on playtime to make more room for academic studies, while at home children's lives are increasingly filled with organized activities intended to help them learn. Today globally 61% of parents surveyed in the Dirt is Good Qualitative Study said that children don't know how to play without using technology.

    Outdoor Classroom Day is making playing time happen, with 22% of participating schools having increased their playtime since joining the campaign. 93% of teachers surveyed saw improvements in children's creativity after playing outside, and 97% believe that time outdoors is necessary for children to reach their full potential.

    Scientific studies show that real play—the active, physical, self-directed play—is essential for children to develop key life skills that are not taught elsewhere. Few would question the value of developing creativity, leadership, resourcefulness, and curiosity.

    The "Boomerang Kids" — young adults who leave to go to college, get married or just show off their independence — are moving back in with mom and dad. Boomerang Kids can be a mixed blessing for parents, both emotionally and financially.

    Especially during hard economic times, adult children head for home. According to a survey, about 40 percent of 2017 graduates still live with their parents. Moreover, 42 percent of the 2015 graduates surveyed said they are still living at home.

    The reasons are many, the first being economics. While the recession(衰退) has touched Americans of all ages, it has been very hard for young adults. This has sent many kids back home. Plus, there is the matter of debt, especially college loans. For many recent graduates, it makes smart economic sense to move back in with their parents where life is comfortable and rent is either low or nonexistent. Then, of course, some return for personal reasons, such as recovering from a divorce or an illness.

    Parents are often glad to help out, both emotionally and financially. As a result, the arrangement often works to everyone's satisfaction. However, there are risks, especially for the parents. These include not only family tension and misunderstandings, but also money. The return to the family can become a financial burden that can affect the parents' plans and their financial future, especially their retirement, as they try to do too much for their children.

    Some young Cambodians are learning a new sport — skateboarding. The country's first skateboard park is located on the grounds of a local charity group at the edge of Phnom Penh, the capital.

    Sports like Khmer boxing and soccer are wildly popular in Cambodia. But Chea, who has been skating for 6 months, says skating has already become his favorite sport.

    The skaters are learning tricks like launching off a jump or half-pipe and flying through the air on their narrow wooden boards.

    A non-governmental organization called Skateistan Cambodia organizes weekly programs at the park. Skateistan started its work in Afghanistan years ago. Rory Burke is working with the group which expanded to Cambodia last year.

    Rory Burke points out, "Yeah, it's definitely not a typical Cambodian pastime (消遣). And I think the idea of 'why skateboarding is that it's not been done before here. We want to use skateboarding as something saying, 'Hey, this is new, this is something different. And that kind of itself becomes a little bit of hook. People see it and they think and they say, "Wow, 'what is that?', and they want to get involved. "

    Skateistan partners with local groups that work with young people. The park is on the grounds of the group known as PSE, where children attend school and learn a trade. There are almost one hundred twenty participants. They all come from troubled lives.

    Seventeen-year-old Sang Rotha is a student at PSE. "Sometimes I don't do well on subjects like math," he says, "I feel bad when I find it hard to keep up with my lessons. So that is why I skateboard—to improve my bad feelings. "

    He says he began skateboarding more than a year ago. Before he started training, it seemed very easy. But it was very difficult to learn tricks, and he got hurt a lot from falling off.

    Rory Burke says learning to deal with the difficulties is part of the lesson for these young skateboarders.

Hair Loss (Alopecia)

    Information about male pattern baldness(秃顶) causes, triggers and treatment in the UK.

    In contrary to popular belief, hair loss­or alopecia­can start at any age. While it is associated with mature males, and statistics show it does mainly affect men above 40, the reality is you can notice symptoms in your 30s, or even 20s and teen years.  The NHS statistics state that 25% of men start losing their hair by the time they reach 30. The most common form of hair loss is male pattern baldness­also known as androgenic alopecia­that affects more than half of men around the world.

    One option many men seek is treatment to avoid further hair loss, especially early on in the process. With treatments, such as Propecia, that specifically target male pattern baldness, it is possible to stop hair loss completely and even encourage fresh new hair growth.

    What is alopecia?

    Alopecia is the medical term for hair loss. Most commonly affecting males, hair loss in men is caused by an increased sensitivity to the male sex hormones (androgens). The type of alopecia you have (as well as hereditary and external factors) can influence levels of hair loss. The most common type of hair loss (alopecia) is male and female pattern baldness. Other types include：

    * Alopecia areata (patches of baldness, usually on the scalp)

    * Scarring alopecia (hair loss directly affecting the hair follicles)

    * Telogen effluvium (hair thinning over a larger area on the top of the head, rather than bald patches)

    * Anagen effluvium(most commonly caused by cancer treatments such as chemotherapy and radiotherapy)

Children who were behind in their development at age 4-5 were almost three times as likely to have been out of education,employment,or training at age 16-17,analysis of pupil data has found. 

4-5-ycar-olds in England are assessed by the Early Years Foundation Stage Profile,and those who reach the boundary of a"good level of development"are considered"school ready". 

The new study in the journal BMC Public Health has found a significant gap in Not in Education,Employment or Training (NEET)outcomes between those who were ready and unready for primary school. The research drew on data from more than 8,000 Bradford young people whose records are linked as part of the Connected Bradford project. The research found that 11%of children who were not school ready went on to be NEET at 16-17, compared to just 4%of children who were school ready. 

Lead author Dr Matthew Warburton,Research Officer at Leeds' School of Psychology, said:"These findings tell us that there are clear,early indicators for children and young people being at risk of disadvantage in late adolescence. As schools routinely collect this data,the research could be used to kickstart early intervention in schools based on primary school readiness. "

The research team,which also included academics from Lancaster University and the Bradford Institute for Health Research,say this shows a clear need for early intervention by schools to reduce disadvantage in later life. 

This echoes the message from a series of N8 Child of the North and Centre for Young Lives reports on the need to put children and young people first. Senior author Dr Amy Atkinson,Lecturer in the Department of Psychology at Lancaster University said:"Data from the Early Years Foundation Stage Profile is readily available for millions of children and young people in England. This information could,and should,be used to identify pupils at increased risk of becoming NEET. "