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.

    I was with a group of businessmen, and we were dealing with a question — what is a good person?

    At a certain point during the discussion, one of the students, a young man of about 30, described an event that happened at Christmas. He and his five-year-old son were decorating the Christmas tree, and a little boy came to the front door begging. If you ever visit Mexico, you will see that the people there take begging as nothing to get upset about and nothing to get embarrassed by.

    So, this little boy came to the door, a boy about the same age as my student's son. The father and the son went to the front door, and the father went back with his five-year-old son and said to him, “Give him one of your toys.” At the words, the little boy quickly picked up one toy, and his father said to him, “No, no, give him your favorite toy.”

    And the little boy, like a little tiger, said, “No way!” He cried; he refused. But the father, like a big tiger in a way, insisted gently, “No, you must give him one of your favorite toys.”

    And finally the boy, with his head down, picked up a toy he had just gotten. The father waited in the living room, and the boy walked to the front door with the toy in his hand. The father waited and waited.

    What do you think happened?

    After a couple of minutes, his son came running back into the living room, his face lighted up. “Daddy,” he said, “can I do that again?” I think I have got the answer to the question.

    Valentine's Day is named after Saint Valentine, an early Christian churchman who helped young lovers. Valentine was killed for his Christian beliefs on February 14 more than 1,700 years ago, but the day that has his name is even earlier than that.

More than 2,000 years ago, the ancient Romans celebrated a holiday for lovers. As part of the celebration, girls wrote their names on pieces of paper and put them in a large container. Boys reached into the container and pulled one out. The girl whose name was written on the paper became his lover or sweetheart for a year. Today, lovers still put their names on pieces of paper and they send each other Valentine's Day cards that tell of their love. Sometimes they also send gifts, like flowers or chocolate candy. Americans usually send these gifts and cards through the mail system. But some used another way to send this message. They have it printed in a newspaper. The cost is usually a few dollars. Some of the messages are simple and short, “Jane, I love you very much.” Others say more. This one, for example, “Roses are red. Violets are blue. I hope you love me as much as I love you. Forever, Mary.”

    Most of the newspapers that print such messages are local, but USA Today is sold throughout the United States and 90 other countries as well. This means someone can send a Valentine message to a lover in a far-away city or town almost anywhere in the world. These messages cost 80 dollars and more. An employee of USA Today says readers can have a small heart or rose printed along with their messages this year. Will this kind of Valentine's Day message reach the one you love? Well, just make sure he or she reads the newspaper.

    I believe in the power of science fiction, not just for its capacity to transform dreams into reality, but also for its power to bond together those who share a common vision of the future. For me, that's true for my relationship with my dad. Some fathers and sons bond over sports, fishing or hunting, but my dad and I bond over Star Trek. We tried a trip to Disney World, but one of my earliest memories wasn't Mickey, but a Klingon battle cruiser(巡洋) on the screen.

    Over the years, nearly every setting and situation has become far away for my dad and me. When it's warm at night, we're not driving along some dark streets in Indiana, but going at a slow speed with stars dimly shining. Both of us are thinking of them, without needing to say a word. All these visions of other universes have together created a private universe for my dad and me.

    Gene Rodenberry, creator of Star Trek, once said, " Science fiction is a way of thinking, a way of logic that bypasses(绕过)a lot of nonsense. It allows people to look directly at important subjects. "A lifetime of science fiction has influenced more than just my relationship with my dad, but has also helped me shape my own hopes for the future. I'm now a science writer.

    Yes, science fiction has made me into a "nerd"(书呆子), and it also has been a source of joy for my family, making me an optimist while enabling me to think critically about the danger of technology. Thank those authors who have shared their visions; the world and my family are better for it. Thank my dad, who is both the best storyteller and the best man I have ever known because he helped me realize the truth of Tennyson's words," Since I dipped into the future, I saw the vision of the world, and all the wonders that would be."

    When I was in primary school, I had an argument with a boy in my class. I thought that "I" was right and that "he" was wrong. But he thought "I" was wrong and "he" was right.

    The teacher asked him to stand on one side of her desk and me on the other. In the middle of her desk was a large and round ball. I could see it was black. She asked what color the ball was. "White," he answered.

    I couldn't believe the boy's answer, because from my side it was obviously black!

    The teacher told me to stand in the boy's place and told him to stand in my place. We changed our places, and then the teacher asked me what color the ball was. I had to answer, "White."

    It was a ball with two different colors. From his side it was white. Only from my side was it black.

    My teacher taught me a very important lesson that day: You must stand in other people's shoes and look at the situation through their eyes in order to truly understand their view.

    Rivers are earthly arteries(要道) for the nutrients, deposits and freshwater that sustain healthy, diverse ecosystems. Their influence extends in multiple dimensions—not only along their length but below­ground to aquifers(蓄水层) and periodically into nearby floodplains.

    They also provide vital services for people by fertilizing agricultural land and feeding key fisheries and by acting as transportation corridors. But in efforts to ease ship passage, protect communities from flooding, and draw off water for drinking and irrigation, humans have increasingly constrained and broken these crucial water ways. “We try to control rivers as much as possible,” says Gunther Grill, a hydrologist at McGill University.

    In new research published in May in Nature, Grill and his colleagues analyzed the barriers to 12 million total kilometers of rivers around the world. The team developed an index(指数) that evaluates six aspects of connectivity—from physical fragmentation (by dams, for example) to flow regulation (by dams or levees) to water consumption—along a river's various dimension. Rivers whose indexes meet a certain threshold(临界值) for being largely able to follow their natural patterns were considered free­flowing.

    The researchers found that among rivers longer than 1,000 kilometers (which tend to be some of those most important to human activities), only 37 percent are not blocked along their entire lengths. Most of them are in areas with a minimal human presence, including the Amazon and Congo basins and the Arctic. On the contrary, most rivers shorter than 100 kilometers appeared to flow freely—but the data on them are less comprehensive, and some barriers might have been missed. Only 23 percent of the subset of the longest rivers that connect to the ocean are uninterrupted. For the rest, human infrastructure is starving estuaries(河口) and deltas (such as the Mississippi Delta) of key nutrients. The world's estimated 2.8 million dams are the main cause, controlling water flow and trapping deposits.

    The new research could be used to better understand how proposed dams, levees and other such projects might impact river connectivity, as well as where to remove these fixtures to best restore natural flow. It could also help inform our approach to rivers as the climate changes, says Anne Jefferson, a hydrologist at Kent State University, who was not involved in the work. Existing infrastructure, she says, “has essentially been built to a past climate that we are not in anymore and are increasingly moving away from.”