America is the country on the move. In unheard of numbers, people of all ages are exercising their way to better health. According to the latest figures, 59 percent of American adults exercise regularly-up 12 percent from just two years ago and more than double the figure of 25 years ago. Even non-exercisers believe they would be more attractive and confident if they were more active. It's hard not to get the message. The advantages of physical fitness are shown on magazine covers, postage stamps, and television ads for everything from beauty soaps to travel books. Exercise as a part of daily life did not catch on until the late 1960s when research by military doctors began to show the good points of' doing regular physical exercises. Growing publicity(宣传) for races held in American cities helped develop a strong interest in the ancient sport of running. Although running has leveled off in recent years as Americans have discovered equally helpful and sometimes safer-forms of exercise.

    As the popularity of exercise continues to increase, so does scientific evidence(根据) of its health benefits. The key to fitness is exercising the major muscle group strongly enough to almost double the heart rate and keep it doubles for 20 to 30 minutes at a time. Doing such physical exercises three times or more a week will greatly improve physical health in about three months.

    When Boris left school, he could not find a job. He tried hard and he wrote letters to many companies until he could not afford to buy any more stamps. Boris began to lose his confidence, then depressed. Still he went on trying and still he failed. He began to think that he had no future at all.

    “Why don't you start your own business?” one of his uncles told him. “The world is a money-locker. You'd better find a way of opening it.”

    “But what can I do?”

    “Get out and have a look round.” advised his uncle. “See what people want; then give it to them, and they will pay for it.”

    Boris began to cycle around the town and found a suitable piece of waste ground in the end. Then he set up his business as a cycle repairer. He worked hard, made friends with his customers and gradually managed to win his good fame. A few months later, he found that he had more work than he could deal with by himself. He found a number of empty shops but they were all no good: in the wrong position, too expensive or with some other problems. But at long last, he managed to find an empty shop in a new place where there were plenty of customers but no competition.

    Boris and his assistant taught themselves how to repair motor-cycles. Slowly but surely the profits increased and the business developed. At last, Boris had managed to open the money-locker and found bank notes and gold coins inside.

    Here is a record of the discussion about AI (artificial intelligence) conducted by several scientists:

    Scientist A: I would say that we are quite a long way off developing the AI, though I do think it will happen within the next thirty or forty years. We will probably remain in control of technology and it will help us solve many of the world's problems. However, no one really knows what will happen if machines become more intelligent than humans. They may help us, ignore us or destroy us. I tend to believe AI will have a positive influence on our future lives, but whether that is true will be partly up to us.

    Scientist B: I have to admit that the potential consequences of creating something that can match or go beyond human intelligence frighten me. Even now, scientists are teaching computers how to learn on their own. At some point in the near future, their intelligence may well take off and develop at an ever-increasing speed. Human beings evolve biologically very slowly and we would be quickly substituted. In the short term, there is the danger that robots will take over millions of human jobs, creating a large underclass of unemployed people. This could mean large-scale poverty and social unrest. In the long term machines might decide the world would be better without humans.

    Scientist C: I'm a member of the Campaign to Stop Killer Robots. Forget the movie image of a terrifying Terminator stamping on human skulls and think of what's happening right now: military machines like drones, gun turrets and sentry robots are already being used to kill with very little human input. The next step will be autonomous “murderbots” following orders but finally deciding who to kill on their own. It seems clear to me that this would be extremely dangerous for humans. We need to be very cautious indeed about what we ask machines to do.

    Many people don't consider their breakfast without a glass of milk. Right now, cows, buffalos, goats and sheep provide most of the world's milk. But soon, people could get milk from roaches(蟑螂).

    That isn't as crazy as it might sound. New research shows this “milk” is super-nutritious. What's more, some scientists have already begun referring to a lot of insects as source of milk.

    In 2004, Subramanian Ramaswamy started studying milk crystals found inside the roach. At the time, he was teaching biochemistry at the University of Iowa City.

    To learn more about the milk crystal from roaches, the scientists used X-rays to look at the atoms in it. The data basically revealed the chemical recipe of the roach crystal. They showed that roach milk is a “complete food”. It contains sugar with a fatty acid stuck to it. Fatty acids are the building blocks of fats. The protein in the milk is also full of essential amino(氨基的) acids, which are the building blocks of proteins. Since our bodies can't produce the “essential” ones, we need to get them from our food. And so do baby roaches.

    Barbara Stay, a biologist at Iowa University, also worked on the new study. She says the new data show that the roach milk is “three times more nutritious than cow's milk and four times more nutritious than buffalo's milk”.

    Ramaswamy would like to see roach milk turned into a protein supplement to feed hungry people. But not everyone is confident that it can be done.

    Marcel Dicke studies insects as a potential source of human food at Wageningen University in the Netherlands. Dicke says this is a “sound study”. However, in his opinion, “Extracting(提取) milk from roaches can only likely be done in a destructive way with only small quantities”. That means you'd have to raise and kill many bugs to get even tiny quantities of the milk.

    People say money doesn't buy happiness, but how much money you make can affect the way you experience it?

    While it's true that money can't buy happiness, having money has certain benefits. For example, money can buy you time to do things that make you happier, and giving away some of your money can make you happier as well. Now scientists from the University of California at Irvine have found that how much money you make may impact (影响) how you experience happiness; higher earners are more likely to experience positive emotions focused on themselves, while lower earners are more likely to experience positive emotions focused on connecting with other people.

    Scientists used data from an existing survey of 1,519 U.S. adults between the ages of 24 to 93, to be representative of the entire U.S. population. From the survey, scientist collected the household income of each person and analyzed how each person experienced the seven emotions that are believed to cause happiness: amusement, admiration, compassion, satisfaction, enthusiasm, love, and pride.

    What they found was that higher earners were associated with the happiness-related emotions of satisfaction, pride, and amusement, all of which are self-focused in nature. Lower earners were associated with more other-oriented (他人指向) happiness-related emotions: compassion, love, and admiration. There were no differences observed with enthusiasm.

    As to reasons for the difference, the researchers suppose that while pride and satisfaction may reflect upper class individuals' (个人) desire for independence, increased love and compassion may help lower class individuals form more harmonious (和谐的), interdependent bonds to help deal with their more threatening environments. In other words, the researchers are not saying that one way of getting happiness is better than another, but rather that the way one obtains happiness may be a product of existing and coping within one's particular circumstances.

    The Guggenheim Museum attempts to help educators connect students with art. It offers programs for educators, including free arts curricula, professional development courses and workshops, as well as professional meet-and-greets that pair artists with public school teachers throughout New York City.

    •Visiting with your students

    The museum offers a variety of ways for educators and their students to visit, from self-guided tours to a guided experience.

    •Arts curriculum online

    The Guggenheim produces free curriculum materials on exhibitions for educators to use both during school visits and in the classroom. While the material focuses on recent exhibitions, a comprehensive range of lessons cover many works and artists in the museum's collection.

    •Learning Through Art

    Learning Through Art sends experienced teaching artists into New York City public schools, where they work with classroom teachers to develop and facilitate art projects into the school curriculum.

    •Education facilities

    Housed in the Sackler Center for Arts Education, the Guggenheim's education facilities include studio art and multimedia labs, a theater, an exhibition gallery, and a conference room.