The idea of being able to walk on water has long interested humans greatly. Sadly, biological facts prevent us ever accomplishing such a thing without artificial aid—we simply weigh too much, and all our mass pushes down through our relatively small feet, resulting in a lot of pressure that makes us sink.

    However, several types of animals can walk on water. One of the most interesting is the common basilisk Basilicus basilicus, a lizard (蜥蜴)native to Central and South America. It can run across water for a distance of several meters, avoiding getting wet by rapidly hitting the water's surface with its feet. The lizard will take as many as 20 steps per second to keep moving forward. For humans to do this, we，d need huge feet that we could bring up to our ears in order to create adequate w hitting. ''

    But fortunately there is an alternative : cornflour. By adding enough of this common thickening agent to water (and it does take a lot), you can create a “non-Newtonian” liquid that doesn't behave like normal water. Now, if the surface of the water is hit hard enough, particles(粒子）in the water group together for a moment to make the surface hard. Move quickly enough and put enough force into each step, and you really can walk across the surface of an adequately thick Liquid of cornflour.

    Fun though all this may sound, it's still rather messy and better read about in theory than carried out in practice. If you must do it, then keep the water wings handy in case you start to sink--and take a shower afterward!

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    When I was 16 years old, I made my first visit to the United States. It wasn't the first time I had been abroad. Like most English children I learned French at school and I had often been to France, so I was used to speaking a foreign language to people who didn't understand English. But when I went to America I was really looking forward to having a nice easy holiday without any language problems.

    How wrong I was! The misunderstanding began at the airport. I was looking for a public telephone to give my American friend Danny a ring and tell her that I had arrived. A friendly old man saw me looking like being lost and asked if he could help me.

    “Yes,” I said. “I want to give my friend a ring.”

    “Well, that's nice,” he said. “Are you getting married? But aren't you a bit young?”

    “Who is talking about marriage?” I replied. “I just want to give my friend a ring to tell her I've arrived. Can you tell me where there's a phone box?”

    “Oh!” he said. “There's a phone downstairs.”

    When at last we did meet up, Danny explained the misunderstanding to me.

    “Don't worry,” she said to me. “I had many difficulties at first. There are lots of words which the Americans use differently in meaning from us British. You'll soon get used to all the funny things they say. But most of the time British and American people can understand each other!”

    A young woman sits alone in café sipping tea and reading a book. She pauses briefly to write in a nearby notepad before showing her words to a passing café waiter: "Where are the toilets please?" This is a familiar scene in Tokyo's so-called "silent cafes", where customers are not allowed to speak, and only communicate by writing in notepads.

    The concept rises by a desire to be alone among young Japanese, a situation brought by economic uncertainly, a shift in traditional family support structures and the growing social isolation. The phenomenon is not limited to coffee shops but covers everything from silent discos, where participants dance alone wearing wireless headphones connected to the DJ, to products such as small desk tents designed for conversation-free privacy in the office. One Kyoto company even offers single women the opportunity to have a "one woman wedding" – a full bridal affair, complete with white dress and ceremony, and the only thing missing is the groom. The trend has its own media expression – "botchi-zoku", referring to individuals who consciously choose to do things completely on their own.

    One recent weekday afternoon, Chihiro Higashikokubaru, a 23-year-old nurse, travelled 90 minutes from her home, to Tokyo on her day off in order to enjoy some solo time. Speaking quietly at the entrance of the café, Miss Higashikokubaru said: "I heard about this place via Twitter and I like the idea of coming here. I work as a nurse and it's always very busy. There are very few quiet places in Tokyo, and it's a big busy city. I just want to come and sit somewhere quietly on my own. I'm going to drink a cup of tea and maybe do some drawings. I like the idea of a quiet, calm atmosphere."

    The desire to be isolated is not a new concept in Japan, home to an estimated 3.6 million "hikikomori" – a more extreme example of social recluses（隐士）who withdraw completely from society.

    Over the past couple of days, on our local Freecycle page there have been a lot of wanted posts, all from the same person, basically asking for everything you'd need to set up a house from scratch.

    One of the things they asked for was a queen-sized bed. At that time we just happened to have an extra one, so I messaged them. They immediately came in the afternoon. The people who came, two ladies and a man, are actually friends of another woman named Jenny who owned a young boy. This woman has escaped from a dangerous, violent relationship and these friends of hers are helping her and her son start over again, with everything from furniture to toothbrushes on their list of needs.

    While they were here, I also gave them one of our spare bookcase and some coffee cups. I even asked them to keep in touch in case they needed anything else—I have a way of connecting people with things. I offered the woman a cupboard we had as well; her friends just needed to see if there was a place and/or a need for it in their friend's new home.

    I was so excited to meet those loving people, who were obviously willing to help their friend. It was clear how protective they felt of this woman and her boy, how much they love her and wanted her to have a happy and safe life, and to spend even a few minutes with people like that is an experience I'll remember for a long, long time.

    A quick thank-you to all who have sent more donations over the last couple of days, as well as lovely messages of thanks and blessings. Sometimes it's hard to keep up with it all, but it's a problem I'm happy to have.

    Teenagers who talk on the cell phone a lot, and hold their phones up to their right ears, score worse on one type of memory test. That's the finding of a new study. That memory impairment might be one side effect of the radiation (放射线) that phones use to keep us connected while we're on the go.

    Nearly 700 Swiss teens took part in a test of figural memory. This type helps us remember abstract (抽象的) symbols and shapes, explains Milena Foerster. The teens took memory tests twice, one year apart. Each time, they had one minute to remember 13 pairs of abstract shapes. Then they were shown one item from each pair and asked to match it with one of the five choices. The study volunteers also took a test of verbal memory. That's the ability to remember words. The two memory tests are part of an intelligence test. The researchers also surveyed the teens on how they use cell phones. And they got call records from phone companies. The researchers used those records to figure out how long the teens were using their phones. This allowed the researchers to work out how big a radiation exposure (接触) each person could have got while talking.

    A phone user's exposure to the radiation can differ widely. Some teens talk on their phones more than others. People also hold their phones differently. If the phone is close to the ear, more radiation may enter the body, Foerster notes. Even the type of network signal that a phone uses can matter. Much of Switzerland was using an older "second-generation" type of cell phone networks, the study reports. Many phone carriers (通讯公司) have moved away from such networks. And more companies plan to update their networks within the next few years.

    The teens' scores in the figural memory tests were roughly the same from one year to the next. But those who normally held their phones near the right ears, and who were also exposed to higher levels of radiation, scored a little bit worse after a year. No group of teens showed big changes on the verbal memory test. Why might one type of memory be linked to cell phone use, but not another? Foerster thinks it could have to do with where different memory centers sit in the brain. The site that deals with the ability to remember shapes is near the right ear.

    People in Japan tend to live longer and stay healthier in their later years, with an increasing number of old people living alone. Japan is on a fast track to "ultra-age" with people aged 65 or above accounting for 28 percent of its total population in 2019；it was 26.7 percent in 2017. On the other hand, the number of births in 2019 fell to its lowest (about 941,000) since records began in 1899.

    Demand for care services for elderly people has increased. A shrinking (缩小) working population means fewer able-bodied adults are available to look after the elderly. State-provided facilities for the elderly are not enough which causes elderly people to turn to private ones but they are expensive.

    The country will be short of 380,000 of health nurses by 2025. The government has to turn to advanced robots to meet the shortage. A study found that using robots encouraged one third of the people to become more active and independent. Yet there is no robot that can provide the emotional support to the elderly.

    Japan provides a case study for China, which is also faced with a fast aging population. 17.23 million babies were born in China in 2019, about 630,000 fewer than in 2018. People aged 60 accounted for 17.3 of China's population in 2019. With a shortage of elderly care facilities and unbalanced supply, China may find it hard to deal with the rapidly increasing number of senior citizens.

    To meet the challenge, the Chinese government should make policy changes, which Japan is unwilling or unable to do or even consider. China should pay attention to the signals its aging population is sending and take proper and timely action.