We are naturally drawn to friends and colleagues with familiar voices, scientists have found. People prefer those who have a similar accent, intonation and tone of voice to themselves, they discovered.

    Previous research has focused on how male or female a voice sounds. Men with deeper voices and women with slightly higher voices were thought to sound more attractive, because they suggest a bigger or a smaller body.

    But the new study, published by a linguistics expert in Canada, suggests there is a more complex mechanism (机制) at play. Dr Molly Babel, from the University of British Columbia in Canada, said, “The voice is an amazingly flexible tool that we use to construct our identity. Very few things in our voices are changeless, so we felt that our preferences had to be about more than a person's shape and size.”

    She recorded 30 volunteers' voices and asked each to rate the others' attractiveness on a range from one to nine. Each participant was from western America, with similar accents. The people we assessed were all in the same dialect group, but they showed that dialect to different degrees.

     “We seem to like people who sound like we sound, and we like people who fit within what we know,” Dr Babel said. She also found that breathy voices in women—typified by the famous American actress Marilyn Monroe-were seen as more attractive.

    The breathy tone, caused by younger and thinner vocal cords (声带), implied youthfulness and health. A creaky (咯吱作响的) voice, suggesting a person has a cold, is tired or smokes, was seen as unattractive. The participants preferred men who spoke with a shorter average word length and deeper voices.

Yellowstone Weather

    Yellowstone National Park is at high altitude. Most of the park is above 7,500 feet (2,275 meters).

    Yellowstone's weather is unpredictable. In summer, it may be warm and sunny with temperatures in the high 70s. At night in any given month, the temperature may drop close to freezing. So it is best to come prepared for cold evenings and mornings, especially if you are camping or hiking. When you leave your campsite, please leave it prepared for possible thundershowers and wind.

    A sunny warm day may become fiercely stormy with wind, rain, sleet and sometimes snow. Without enough clothing, and easy day hike or boat trip can turn into a battle for survival.

    Girls who lack confidence in school have a new champion. She is only 10 years old. Alice Tapper, a fifth - grader says, that her goal is to encourage girls of all ages to “be more confident in raising their hands”. Alice cared so much about the issue (问题) that she helped create a Girl Scout badge (徽章).

    The pink badge—Alice chose her favorite color—shows three hands reaching for the sky. It says, “Be brave. Raise your hand.”

    Alice's idea came during a fourth - grade field trip to Jamestown, Virginia. She found that boys raised their hands to answer questions even though they weren't sure of the answers. The girls just listened quietly.

    “Girls are afraid to raise their hands because they get shy. They have to be 90 percent sure, while boys just raise their hands and say, 'I know it,'” Alice said during a recent interview. She added that girls should have confidence, step up, and become leaders by raising their hands for women are equal to men.

    Alice's “Raise Your Hand” badge has become wildly popular, and not just in the United States. “People in Japan and China want to use the badge,” she said. “We sold out the badge quickly, but we're making more.”

    Alice wants to be a teacher when she grows up. But first, she wants to see a revolution in confidence for girls of all ages. She knows that won't happen overnight. “ It takes time,” Alice said, “but I can speed up the process.”

    Two Chinese sisters have landed a dream trip to Buckingham Palace and the Peppa Pig World theme park in the UK. Lately, their mother helped them express their wish online to meet Queen Elizabeth II, which not only caught millions of social media users' attention but also the attention of the British ambassador (大使) to China.

    Five-year-old twins Mi Ai and Mi Ni, who live in Beijing, appeared in a video on social media platform Weibo last week, where they spoke of their love of British cartoon Peppa Pig and their keen interest to visit the Buckingham Palace. Mi Ni said she and her sister wanted to visit the gardens at Buckingham Palace, just like Peppa Pig and her friends did in the cartoon program.

    The British Ambassador answered their call with her own video, inviting the twins to her house in Beijing. "Hello Mi Ni and Mi Ai," she said. "I'm the British ambassador. I'd like you to come and visit me in my house in Beijing and we can perhaps have tea and cookies in a British style." The twins accepted the ambassador's invitation and joined her for a traditional afternoon tea on Monday, when they ate cake and drew pictures of their favorite characters from Peppa Pig.

    The ambassador has made arrangements for the girls and their parents to tour the UK. They are going to tour the studios where Peppa Pig is made, take a trip to Peppa Pig World in Hampshire and visit Buckingham Palace. The queen has not yet said if she will have time to welcome the girls.

    The Peppa Pig series, introduced in the mid-2000s in China, has become extremely popular among Chinese children and adults. As this year is the Year of the Pig according to Chinese tradition, the country has set to mark the Chinese New Year with a film starring Peppa Pig, where audiences can see a number of Chinese cultural elements (元素).

    Rich countries are racing to dematerialise payments. They need to do more to prepare for the side-effects.

    For the past 3,000 years, when people thought of money they thought of cash. Over the past decade, however, digital payments have taken off— tapping your plastic on a terminal or swiping a smartphone has become normal. Now this revolution is about to turn cash into an endangered species in some rich economies. That will make the economy more efficient—but it also causes new problems that could hold back the transition(转型).

    Countries are removing cash at varying speeds. In Sweden the number of retail cash transaction per person has fallen by 80% in the past ten years. America is perhaps a decade behind. Outside the rich world, cash is still king. But even there its leading role is being challenged. In China digital payments rose from 4% of all payments in 2012 to 34% in 2017.

    Cash is dying out because of two forces. One is demand— younger consumers want payment systems that plug easily into their digital lives. But equally important is that suppliers such as banks and tech firms (in developed markets) and telecoms companies (in emerging ones) are developing fast, easy-to-use payment technologies from which they can pull data and pocket fees. There is a high cost to running the infrastructure behind the cash economy—ATMs, vans carrying notes, tellers who accept coins. Most financial firms are keen to abandon it, or discourage old-fashioned customers with heavy fees.

    In the main, the prospect of a cashless economy is excellent news. Cash is inefficient. When payments dematerialise, people and shops are less open to theft. It also creates a credit history, helping consumers borrow.

    Yet set against these benefits are a couple of worries. Electronic payment systems may risk technical failures, power failure and cyber-attacks. In a cashless economy the poor, the elderly and country folk may be left behind. And a digital system could let governments watch over people's shopping habits and private multinationals exploit their personal data.

The American Psychological Association（APA） has issued its first advisory on social media use in adolescence（青春期）. What's most striking in its data based on recommendations is how little we really know about how these apps affect our kids.

The relative newness of platforms like Snapchat and Tik Tok means little research is available about their long-term effects on teen and tween brains. Getting better data will require significant funding—and much more openness from tech companies.

"What little evidence we do have unsurprisingly suggests that social media trades on motivators that aren't great for young brains. Many kids' first exposure to social media occurs at the worst possible time when it comes to brain development," says Mitch Prinstein, a psychologist and neuroscientist at the University of North Carolina（UNC）.

"Things like 'button and artificial intelligence（in general）' are going to affect young people's brains in a way that's very different from adult brains when it comes to the desire to stay online and to say or do almost anything to get followers." When it comes to social interactions, he compares kids' brains to a car with a huge gas pedal and weak brakes（刹车）.

Earlier this year, Prinstein and his UNC colleagues published the results of one of the first studies of how the adolescent brain reacts to social media. The team surveyed a group of middle schoolers to understand their social media habits, and then stuck them in an MRI machine to watch their brains as they reacted to social rewards or punishments. They found that 12-year-olds who habitually checked social media had distinct neural patterns, with more activities over time in parts of the brain associated with motivation, salience（or where attention is focused） and cognitive control.

The team didn't weigh in on whether those differences were good or bad, or whether the relationship was causal or correlational. But their work points to the need for more research. It should also remind parents of the need to be keenly aware of social media's hidden influence on still-developing brains.