When we talk about stars, especially women stars, it seems that they are always young, pretty and own charming body shapes. But recently a Britain's Got Talent（英国达人）star Susan Boyle has changed our views absolutely.

    Simon Cowell, one of the judges of the talent show spoke of his shock over Ms Boyle's voice. "This lady came up, and I'm thinking, 'This will take five seconds and I can go to have a cup of tea'. That changed when she began to sing I Dreamed to Dream from Les Miserables. She knew we were going to have that reaction and just to see that look of satisfaction on her face through -it was one of my favorite moments," Cowell said.

    The performance was posted on line and before long, the 47-year-old Scottish woman has been famous all over the world.

    Speaking from her home in Scotland, Ms Boyle said that she hasn't thought of changing her appearance. She said that her friend helped her with make-up. "I mean, that's hardly a makeover（改头换面）," she added. Ms Boyle also spoke of the reason she first began to explore her vocal talents, "I was kind of slow at school, so getting like singing was a good way of hiding behind that and thus it built my confidence."

    Most people know something about the greenhouse effect. Factories send gasses such as carbon dioxide, or CO₂, into the atmosphere, the air around the earth. In the past, this wasn't a problem because trees absorbed the CO₂. But now people in many countries are cutting down billions of trees all around the world. At the same time, factories are sending more CO₂ into the atmosphere. It's difficult to believe, but factories put billions of tons of CO₂ into the atmosphere every year. One ton is over 2000 pounds, so it is a lot of pollution. There is too much CO₂ and there aren't enough trees, so the world is getting warmer. In other words, we have a greenhouse effect. This is terrible for the environment.

    What can we do about this? Firsts we can stop using so much coal and oil. We can learn to use different kinds of energy: the sun, wind, steam from volcanoes，and heat from inside the earth. Second, instead of cutting down trees, we should plant more trees. One tree can absorb ten pounds of carbon dioxide every year.

    The trees are good for the earth's atmosphere and for Guatemala (拉丁美洲国家危地马拉).In small towns and villages in Guatemala, most women are poor and have hard lives. Trees help them in three ways. First, the Connecticut factories pay them to plant the trees. Their pay is com, not money. The com is good for their children. Second, these women know a lot about their environment. They know where to plant when to plant, and what kinds of trees to plant. For example，they plant many fruit trees. The fruit gives them vitamins for their families^, diets. Other trees are good for firewood. In a few years, the women won't spend so much time looking for firewood. Third, all these trees are good for the soil. Now rain can't wash the soil down from the mountains so easily.

    This plan isn't enough to stop the greenhouse effect. However, it's a start. The woman of Guatemala are helping themselves and helping their environment.

    Known for its historic stone paths and traffic-jammed streets, France forgoes（放弃）traditional bricks and pavement for shiny solar panels（嵌板）with its new roadway project. French officials announced plans to construct a 1,000-kilometer-long solar roadway, with each kilometer capable of providing enough cheap, renewable energy to power 5,000 homes.

    “The maximum effect of the program, if successful, could be to furnish 5 million people with electricity, or about 8 percent of the French population,” Segolence Royal, France's minister of ecology and energy, said at a conference, reports Global Construction Review.

The street — or “Wattway”—was made possible through the cooperation between the National Institute of Solar Energy and French civil engineering firm Colas. Tests for the road will begin in the spring. The entire project will take an estimated five years to complete, but builders won't have to destroy existing roads in the meantime. Only about a quarter of an inch thick, the solar panels can simply be glued on top of existing streets and are durable（耐用的）enough to bear heavy traffic and weather conditions.

    Despite the bad traffic Parisians associate with their journey to work every day, the average French roadway is packed for only 10 percent of the day, according to Colas' figures. That will leave the solar street with the majority of the day to gather energy from the sun, which makes the project quite promising. The panels collect solar power through a thin layer of polycrystalline silicon（多晶硅）and change it into electricity. Electrical connections can be put into existing traffic structures.

    France won't be the first country to roll out a solar road. A 70-meter solar bike path was set up in the Netherlands in 2014. Within six months, the path had created enough to power a house for an entire year.

    One day, a patient came to see me. He worked as a waiter in a restaurant and his problem was acid reflux (胃酸倒流), a disease that influences as many as 40 percent of Americans, a marked increase in recent years. Reflux can lead to esophageal (食道的) cancer, which has increased by about 500 percent since the 1970s. The drugs we use to treat reflux don't always work and may even increase the risk of developing cancer when used long term.

    What is responsible for these worrying developments? For one, our poor diet, with its huge increases in the intake of sugar, fat, soft drinks, and unhealthy foods. But another important fact has been overlooked: dinnertime. Over the past twenty years, the time of my patients' evening meals has become later and later. Dinner — already pushed back by longer work hours — is often further delayed (推迟) by activities such as shopping and exercise.

    In my experience, the single most important treatment for reflux is to avoid late eating. A patient with reflux came to see me because her father and uncle died of esophageal cancer, and she was afraid of getting it too. Her nightly routine (常规) included a 9 p. m. dinner with at least two bottles of red wine. The reflux was serious, and changes were needed.

    She listened, then did not come back to see me for a year. “For the first two months, I just hated you,” she told me, “and for the next two months, I was having some trouble eating. I guessed I was going to die of esophageal cancer.” Then she added, “You know, we're the reason that it's not so easy to get 6 p.m. reservations (预约) at the good restaurants anymore.”

    To stop the increase in reflux disease, we have to stop eating at least three hours before bed. As for my waiter patient? I told him to eat dinner before 7 p.m. Within six weeks, his reflux was gone.

    Laughter is part of the universal human vocabulary. All members of the human species understand it. Unlike English or French or Swahili, we don't have to learn to speak it. We re born with the capacity to laugh.

    Very little is known about the specific brain mechanisms responsible for laughter. Contrary to folk wisdom, most laughter is not about humor; it is about relationships. To find out when and why people laugh, I went with several assistants to local malls and recorded what happened just before people laughed. Over a 10-year period, we studied over 2, 000 cases of naturally occurring laughter.

    We found that most laughter does not necessarily follow jokes. People may laugh after a variety of statements, such as, "Here comes Mary," "How did you do on the test?" or "Do you have a rubber band?" These certainly aren't jokes.

    We believe laughter evolved from the panting (喘气的) behavior of our ancient ancestors. Today, if we tickle (使发痒) chimps, they don't laugh. But, instead, they produce a panting sound. That's the sound of ape laughter, and it's the root of human laughter.

    Apes laugh in the kinds of situations that lead to human laughter, like games that involve chasing. Other animals produce sounds during play, but they are so different from laughter. Rats, for example, produce high sounds during play and when tickled, but these are very different in sound from human laughter.

    Laughter is often positive, but it can be negative too. There's a difference between "laughing with" and "laughing at". People who laugh at others may be trying to drive them out of the group.

    No one has actually counted how much people of different ages laugh, but young children probably laugh the most. At ages 5 and 6 we probably laugh more than at any other times. Adults laugh less than children, probably because they play less.

    Work now underway will tell us more about the brain mechanisms behind laughter, how it has evolved, and why we're so susceptible to tickling.