Sumeja Tulic had moved from London to New York nine months ago to attend journalism school. Yet her time in New York met with a season of never-ending ugliness in politics and acts of terrorism(恐怖主义) around the world. “One day you laugh, and then you're angry,” said Tulic. As she walked toward the subway station, she thought, “I want to see something nice. Enough of this craziness.”

    At the City Hall station, she saw a man resting against a pillar(柱子), the way anyone might, waiting for the train. The stillness was interrupted(打断) by an announcement that the next train was two stations away. Then Tulic saw the man at the pillar falling forward onto the tracks.

    The man who had fallen was not moving. In what seemed like an instant, three men jumped down to help.

    I don't know where these men got the intelligence and the quickness," Tulic said. "The man who fell was about six feet tall and quite heavy. He was kind of stuck in the tracks. It was terrifying to know that the train was coming. Will it stop? Will they succeed in pulling him out?"

    On the tracks, the unconscious(失去知觉的) man was put into a sitting position by the three men, who then lifted him from below to others who lifted from above and rolled him onto the platform. Then the rescuers were themselves rescued, pulled back to safety by helping hands. As soon as they were all clear, the train pulled in. People getting off the train walked around this unconscious man.

    Two of the men who had jumped onto the platform were holding his hands. “They were saying, ‘You're going to be fine,'” Tulic said. “This was an additional layer of goodness.”

    Doctors arrived, and the man was taken to a local hospital with serious but non-life-threatening injuries.

    “That is the greatest thing,” Tulic said. “The infrastructure(基础) in this city of millions is the people themselves providing, being there for others, without even knowing the person, who he is. It was beautiful to see.”

    It's Friday morning in the year 2050, and you're running late. You got carried away watching the music video that is playing in the corner of your bathroom mirror while you were brushing your teeth. How will you get to your office at Mega Giga Industries on time?

    A quick check of your Internet-connected refrigerator tells you your train is a bit behind schedule, too. So you decide to drive your environmentally hydrogen fuel（环保氢燃料）car instead-or rather, let your car drive you. It's programmed to know the way and it will get you there without getting lost.

    Settling into your office chair, which changes color to match what you're wearing, you pick up yesterday morning's newspaper. Printed on reusable electronic paper, it rewrites itself. Now it's time for your big meeting. Uh-oh! You've left your handwritten notes at home. No problem. The smartpen you used has stored an electronic copy of what you wrote.

    Your wristwatch videophone（可视电话）suddenly rings. Your best friend's face pops up on the screen asking what you're doing this weekend. Will you play virtual soccer with the U.S. Olympic team? No, no. Your friend says, so you have to take the new elevator (made of microscopic fibers many times stronger than steel) 60000 miles into space.

    Could this scene really take place in just a couple of decades? The researchers who are now developing all these things think so. These high-tech products（高科技产品）may be as common in 20 years as cell phones today.

    Young sunflowers turn and swing every day. New findings add to evidence that the plants are animal-like.

    Harmer, a professor in the University of California at Davis, Department of Plant Biology, carried out a series of experiments on sunflowers in the field, in pots outdoors and in indoor growth chambers.

    By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun. He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move. When plants were moved indoor with a settled overhead light, they continued to swing back and forth for a few days.

    The indoor plants did start tracking the “sun” again when the apparent source of lighting was moved across the room. The plants could reliably track the movement and return at night when the artificial day was close to a 24-hour cycle, but not when it was closer to 30 hours.

    When sunflowers track the sun, the east sides of their stems grew more rapidly than the west sides. At night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day or on the other side at night. A plant growth-regulating hormone (激素), called auxin, appears to be a key driver.

    The “dance” to the sun cycle obviously slows when the sunflower matures (成熟) and its flowers open up. At that point, the plants stop moving during the day and settle down facing the sun in the east.

    “Bees like warm flowers.” Harmer said, adding that the bees are cold-blooded, so landing on a warm flower saves them energy and perhaps feels really good.

    “The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.” he said “We're currently testing this idea.”

    If it had not been for Fan Jinshi and her team, the world cultural heritage at Dunhuang Mogao Grottoes in a remote Chinese desert might have long been destroyed by sand, weather or humans.

    Born and raised in Shanghai, Fan has spent half a century fighting an uphill battle to preserve the ancient Buddhist wall painting at Dunhuang, in Northwest China's Gansu Province. The 1,651-year-old Dunhuang Mogao Grottoes are a huge collection of Buddhist art—more than 2,000 buddha figures and 45,000 square meters of paintings spread among 735 caves. It is China's first UNESCO World Heritage Site.

    Archaeologist Fan was sent to Dunhuang after graduation from Peking University in 1963. While in Dunhuang, a remote village in the desert then, Fan lived in an abandoned temple. At first, she did not even dare to go out to the toilet at night. To protect the treasures from sand and dampness, Fan and other workers put doors on the caves, planted trees and started monitoring temperature and humidity in the caves. They also controlled the number of visitors.

    In the late 1990s, with tourism booming nationwide since national holidays were extended, the local government planned to go public with Dunhuang Mogao Grottoes, but found Fan firmly in their way. “The heritage would have been destroyed if it had been listed,” she said.

    Dunhuang Academy has now photographed and cataloged online all the sculptures and paintings. “Despite our efforts to minimize damage, we can't completely stop them from being eroded. But the digital database will last.”

    Fan was grateful when her husband joined her in Dunhuang in 1986 after 19 years of separation. Her two sons grew up in Shanghai with their aunt.  “I have not been a good mother or wife. With regard to my family, I'm full of guilt,” she said. Fan, 79, retired two years ago as the director of Dunhuang Academy but continues her efforts as a national political adviser.

    Wilbur and Orville Wright were the two youngest sons of Bishop Milton Wright, Wilbur was born on a farm near Millville and Orville was born in August in the house the family would come to occupy for more than 40 years in Dayton.

    Orville would discover in later years that he and Wilbur's first interests in flight began when they were children, with powered rubber-band-helicopter toys that their father would bring home for them from trips around the country. Orville and Wilbur would build duplicates（复制品）of these toys and bounce them off the ceiling. They were just crazy about these things for the reasons that they did not yet understand.

    Both boys loved to solve problems that seemed difficult to others. The more difficult the problem was, the more they saw it as a challenge. Exploring the unknown was such a joy for then that Orville once said, "I can remember when Wilbur and I could hardly wait for the morning to come to get at something that interested us. That's happiness."

    Putting their gift to work, the boys entered the printing business soon after high school. Orville designed and then built a printing press（印刷机）for this enterprise. At first, they did contract printing for other people, and soon one of their customers during the early 1890s was Father Milton's church. They also tried the newspaper business, and although their two newspapers, the West Side News and The Evening Item were considered to be of high quality, Dayton already had daily newspapers, so the Wrights soon returned to contract printing.

    Branching out into other areas, they also opened a bicycle business. Bicycling was the fastest growing sport in the country at that time, and their repair shop soon led them into building bicycles of their own design, often with tools of their own construction, such as the lathe（车床）driven by a one-cylinder gasoline engine built by Orville. The bicycle shop would provide the livelihood（生计）that would allow them to carry out their experiments on airplanes.

    When it comes to medical care, many patients and doctors believe "more is better." But what they do not realize is that overtreatment—too many scans, too many blood tests, too many procedures—may bring harm. Sometimes a test leads you down a path to more and more testing, some of which may be invasive, or to treatment for things that should be left alone.

    Terrence Power, for example, complained that after his wife learned she had Wegener's disease, an uncommon disorder of the immune system, they found it difficult to refuse testing recommended by her doctor. The doctor insisted on office visits every three weeks, even when she was feeling well. He frequently ordered blood tests and X－rays, and repeatedly referred her to specialists for even minor complaints. Even when tests came back negative, more were ordered, and she was hospitalized as prevention when she developed a cold. She had as many as 25 doctor visits during one six－month period. The couple was spending about $30,000 a year for her care.

    After several years of physical suffering and near financial ruin from the medical costs, the couple began questioning the treatment after discussing with other patients in online support groups. "It's a really hard thing to determine when they've crossed the line," Mr. Power said. "You think she's getting the best care in the world, but after a while you start to wonder: What is the purpose?" Mr. Power then spoke with his own primary care doctor, who advised him to find a new specialist to oversee Mrs. Power's care. Under the new doctor's care, the regular testing stopped and Mrs. Power's condition stabilized. Now she sees the doctor only four or five times a year.