For grown-ups, an afternoon snooze(打盹) is often easier said than done. But many of us have probably experienced just how simple it can be to catch some sleep in a gently rocking hammock(吊床). By examining brain waves in sleeping adults, researchers reported in the June 21 issue of Current Biology, a Cell Press publication, that they now have evidence to explain why that is.

    “It is a common belief that rocking causes sleep: we fall asleep in a rocking chair soon and, since ancient times, we cradle our babies to sleep,” said Sophie Schwartz of the University of Geneva. “Yet, how this works had remained a mystery. The goal of our study was made up of two parts: to test whether rocking does indeed improve sleep, and to understand how this might work at the brain level.”

    Schwartz, Michel Mühlethaler, and their colleagues Laurence Bayer and Irina Constantinescu asked twelve adult volunteers to nap on a custom-made bed or “experimental hammock” that could either remain still or rock gently. All participants were good sleepers who didn't typically nap and did not suffer from excessive sleepiness during the day. Each participant took two 45-minute afternoon naps, one with the bed still and one with the bed in motion, while their brain activity was monitored.

    “We observed a faster transition to sleep in each and every subject in the swinging condition,” Mühlethaler said. “Surprisingly, we also observed a dramatic boosting of certain types of sleep-related brain waves.”

    More specifically, rocking increased the length of stage N2 sleep, a form of non-rapid eye movement sleep that normally occupies about half of a good night's sleep. The rocking bed also had a lasting effect on brain activity, increasing slow brain waves and bursts of activity known as sleep spindles(纺锤体).

    Schwartz and Mühlethaler say the next step is to find out whether rocking can improve longer periods of sleep and to find out whether it may be useful for the treatment of sleep disorders, such as insomnia(失眠).

    A few weeks ago, I called an Uber to take me to the Boston airport for a flight home for the holidays. As I slid into the back seat of the car, the warm intonations（语调）of the driver's accent washed over me in a familiar way.

    I learned that he was a recent West African immigrant with a few young children, working hard to provide for his family. I could relate: I am the daughter of two Ethiopian immigrants who made their share of sacrifices to ensure my success. I told him I was on a college break and headed home to visit my parents. That's how he found out I go to Harvard. An approving eye glinted（闪烁）at me in the rearview window, and quickly, we crossed the boundaries of rider and driver. I became his daughter, all grown up – the product of his sacrifice.

And then came the fateful question: "What do you study?" I answered "history and literature" and the pride in his voice faded, as I knew it might. I didn't even get to add "and African-American studies" before he cut in, his voice thick with disappointment. "All that work to get into Harvard, and you study history?"

    Here I was, his daughter, squandering the biggest opportunity of her life. He went on to deliver the age-old lecture that all immigrant kids know. We are to become doctors (or lawyers, if our parents are being generous) – to make money and send money back home. The unspoken demand, made across generations, which my Uber driver laid out plainly, is simple: Fulfill your role in the narrative（故事）of upward mobility so your children can do the same.

I used to feel anxious and backed into a corner by the questioning, but now as a junior in college, I'm grateful for their support more than anything. This holiday season, I've promised myself I won't get annoyed at their inquiries. I won't defensively respond with "but I plan to go to law school!" when I get unrequested advice. I'll just smile and nod, and enjoy the warmth of the occasion.

    As the Chinese Mid-Autumn Festival approaches, mooncakes are turning up all over China, from traditional teashops to Starbucks counters. The holiday is one of China's four most important festivals, and in the weeks before the date arrives, top hotels get into the spirit with lavish(奢华) treats in lovely packaging. Traditionally, the cookie-sized round pastry(馅饼) has a rich thick filling usually made from red-bean or lotus-seed paste and covered by a thin crust. It may also contain yolks from salted duck eggs, integrating a beautiful savory tinge into the sugary taste. Fillings and crusts have become more diverse over time, especially in the hands of skilled pastry chefs. The mooncakes in Chinese culture represent homesickness, and the top crust of each moon-shaped pastry is generally imprinted with the Chinese characters for longevity or harmony.

    This year, the fancy gift boxes that have long driven the mooncake trade are particularly striking and rich with tradition.

    For example, the Fairmont Peace Hotel in Shanghai, built in 1929 and a magnet for Hollywood celebrities in the 1930s, has prepared a selection of mooncake gift boxes with designs inspired by the beauty and elegance of the hotel's famous art deco style. The simplest box of four pieces (red-bean paste, creamy custard, plain cheese, green-bean paste) is 198 yuan($29.64), while more lavish selections of five or six pieces, including mooncakes with egg yolk, run up to 338 yuan for a box.

    Beijing's Nuo Hotel, meanwhile, has created Ming Dynasty (1368－1644) inspired mooncake gift packs based on the design of porcelain vases in the hotel lobby, with the essence of landscape painting using Zhang Dai's poetic passages to show the peaceful harmony of man and nature. The box of six is 158 yuan, and includes mooncakes ranging from cheese mango to charcoal burning fragrant Pu'er tea and white lotus with egg yolk. A box of eight cakes of different flavors is 228 yuan.

    More and more people like bicycling and it is no surprise. It's fun, healthy and good for the environment. Maybe that's why there are 1.4 billion bicycles and only 400 million cars on roads worldwide today. Bikes can take you almost anywhere, and there is no oil cost!

    If you get on a bicycle and ride it, you may discover something new all around you. Stopping and getting off a bike is easier than stopping and getting out of your cars. You can bike to work and benefit from the enjoyable exercise without polluting the environment. You don't even have to ride all the way.

    Folding bikes work well for people who ride the train. Just fold the bike and take it with you. You can do the same on an airplane. A folding bike can be packed in a suitcase. You can also take a common bike with you when you fly. But be sure to look for information by getting on airline websites. Not all airlines are bicycle friendly to travellers.

    Here are some of Health Benefits of Bicycling：

    Bicycling helps to prevent heart diseases.

    Bicycling helps to control your weight.

    A 15­minute bike ride to and from work three times a week burns off five kilos of fat in a year.

    Bicycling can improve your mood.

    Exercise like bicycling has been shown to make people feel better, more relaxed and self-confident.

    Bicycling is healthier than driving.

    Have you heard of the following people? Maybe yes, maybe no. But they may be an inspiration for you.

    The Tree Lady

    Kate Sessions was an American botanist and landscape architect closely associated with San Diego, California. After becoming the first woman to graduate from the University of California, Berkeley, she took a job as a teacher far south in the dry desert town of San Diego. Kate decided that San Diego needed trees more than anything else. Therefore, this young woman single-handedly started a movement transforming the town into the leafy, garden-filled place as it is today.

    The Snowflake(雪花) Man

    Wilson Bentley is one of the first known photographers of snowflakes. His enthusiasm for taking photos began from his boyhood and was often misunderstood in his time, but his determination revealed two important truths: no two snowflakes are alike; and each is surprisingly beautiful. In 1931, he worked with William J. Humphreys of the U.S. Weather Bureau to publish Snow Crystals, a book containing 2500 photographs.

    The Father of His Country

    By the late 1760s, George Washington had experienced firsthand the effects of rising taxes imposed (征收) on American colonists by the British, and came to believe that it was in the best interests of the colonists to declare independence from England. During the American War of Independence, he led the colonial forces to victory. In 1878, he was elected president of the Convention that wrote the U.S. Constitution. Two years later, Washington became American's first president. His retirement from office after two terms established a tradition that lasted until 1940, when Franklin Delano Roosevelt won a third term. The 22^nd Amendment (1951) now limits the president to two elected terms.

    When John was growing up, other kids felt sorry for him. His parents always had him weeding the garden, carrying out the garbage and delivering newspapers. But when John reached adulthood, he was better off than his childhood playmates. He had more job satisfaction, a better marriage and was healthier. Most of all, he was happier. Far happier.

    These are the findings of a 40­year study that followed the lives of 456 teenage boys from Boston. The study showed that those who had worked as boys enjoyed happier and more productive lives than those who had not. "Boys who worked in the home or community gained competence (能力) and came to feel they were worthwhile members of society, "said George Vaillant, the psychologist (心理学家) who made the discovery. "And because they felt good about themselves, others felt good about them."

    Vaillant's study followed these males in great detail. Interviews were repeated at ages 25, 31 and 47. Under Vaillant, the researchers compared the men's mental­health scores with their boyhood ­activity scores. Points were awarded for part­time jobs, housework, effort in school, and ability to deal with problems.

    The link between what the men had done as boys and how they turned out as adults was surprisingly sharp. Those who had done the most boyhood activities were twice as likely to have warm relations with a wide variety of people, five times as likely to be well paid and 16 times less likely to have been unemployed. The researchers also found that IQ and family social and economic class made no real difference in how the boys turned out.

    Working—at any age—is important. Childhood activities help a child develop responsibility, independence, confidence and competence—the underpinnings (基础) of emotional health. They also help him understand that people must cooperate and work toward common goals. The most competent adults are those who know how to do this. Yet work isn't everything. As Tolstoy once said, "One can live magnificently in this world if one knows how to work and how to love, to work for the person one loves and to love one's work."