A small group of people around the world have started implanting(移植) microchips to link the body and the computer.

    Mr. Donelson and three friends, who had driven 100 miles from their homes in Loockport, New York, to have the implants put in by Dr. Jesse Villemaire, whom they had persuaded to do the work, are part of a small group, about 30 people around the world, who have independently put in microchips into their bodies, according to Web-based reports.

    At a shop William Donelson was having a four-millimeter-wide needle put into his left hand. “I'm set,”he said with a deep breath. He watched as the needle pierced(刺穿) the fleshy webbing between his thumb and a microchip was set under his skin. At last he would be able to do what he had long imagined: strengthen his body's powers through technology.

    By putting the chip inside—a radio frequency identification device (RFID)—Mr. Donelson would have at his fingertips the same magic that makes safety gates open with a knock of a card, and bridge and tunnel traffic flow smoothly with an E-Zpass. With a wave of his hand he plans to connect with his computer, open doors and unlock his car.

    Implanting the chip was relatively simple task but very meaningful to Mr. Doneselson, a 21-year-old computer networking student so interested in the link between technology and the body that he has data-input jacks(数据输入插空) inside his body. They might lead to an imagined future when people can be connected directly into computers. His new chip is enclosed in a glass container no bigger than a piece of rice and has a small memory where he has stored the words “Technology”.

    Some doctors have done the piercing in people's homes, and others have implanted chips in their offices after patients signed forms showing the fact that long-term studies have not been done on their safety. Piercers treat the implants much like any other medical operation steps, instructing people to keep the site dry, and advising them that swelling and redness should last a week.

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    Electrical devices (仪器) could soon use power made by human energy. Scientists say they have developed an experimental device that produces electricity from the physical movement of a person walking. British scientist Max Donelan and other scientists in Canada and the United States developed the device.

    The device connects to a person's knee. As the person walks, the device captures energy each time the person slows down. To do this, the device helps with the slowing down movement of the leg. The movements of the walking person push parts of a small machine that produces electricity. Using the device, an adult walking quickly could produce thirteen watts of electricity in just a minute. Donelan says walking at that speed could produce enough power to operate a laptop computer for six minutes.

    There are several possible uses for the device. Developers say it could help people who work in areas without electricity to operate small computers. The device could also be used in hospitals to operate heart pacemakers (起搏器). It could even be used to assist in the movement of robotic arms and legs.

    The experimental version of the device weighs about one and a half kilograms, but it is too costly for most people to buy. But the researchers hope to make a lighter, less costly version. An improved version should be ready in one year.

    The developers hope the device will one day help developing countries. Nearly twenty-five percent of people around the world live without electric power.

    A similar product was invented in 2005 by Larry Rome of the University of Pennsylvania. He created a bag carried on a person's back that also produces power from walking. The knee device does not produce as much electricity as the bag. But the bag requires the walker to carry a load of twenty to thirty kilograms.

Recordings of angry bees are enough to send big, tough African elephants running away, a new study says. Beehives (蜂窝)—either recorded or real—may even prevent elephants from damaging farmer's crops.

    In 2002, scientist Lucy King and her team found that elephants avoid certain trees with bees living in them. Today, Lucy wants to see if African honeybees might discourage elephants from eating crops. But before she asked farmer to go to the trouble of setting up beehives on their farms, she needed to find out if the bees would scare elephants away.

    Lucy found a wild beehive inside a tree in northern Kenya and set up a recorder. Then she threw a stone into the beehive, which burst into life. Lucy and her assistant hid in their car until the angry bees had calmed down. Next，Lucy searched out elephant families in Samburu National Reserve in northern Kenya and put a speaker in a tree close to each family.

    From a distance, Lucy switched on the pre-recorded sound of angry bees while at the same time recording the elephants with a video camera. Half the elephant groups left the area within ten seconds. Out of a total of 17 groups, only one group ignored the sound of the angry bees. Lucy reported that all the young elephants immediately ran to their mothers to hide under them. When Lucy played the sound of a waterfall (瀑布) instead of the angry bees to many of the same elephant families, the animals were undisturbed. Even after four minutes, most of the groups stayed in one place.

Lucy is now studying whether the elephants will continue to avoid the sound of angry bees after hearing it several times. She hasn't tested enough groups yet to know, but her initial (最初的) results were promising enough to begin trials with farmers. She has now begun placing speakers in the fields to see if elephants are frightened away.

    It's true that quite a few most respected scientific authorities have confirmed that the world is becoming hotter and hotter. There^'s also strong evidence that humans are contributing to the warming. Countless recent reports have proved the same thing. For instance, a 2010 summary about the climate science by the Royal Society noted that: The global warming over the last half - century has been caused mainly by human activity.”

    You may not believe that humans could change the planet's climate, but the basic science is well understood. Each year, billions of tons of greenhouse gases are released into the atmosphere because of human activity. As has been known for years, these gases hold heat that would otherwise escape to space, wrapping the planet in an invisible blanket.

    Of course, the earth's climate has always been changing due to “natural” factors such as volcanic eruption or changes in solar, or cycles concerning the Earth's going around the sun. According to the scientific research, however, the warming observed by now matches the pattern of warming we would expect from a build - up of greenhouse gas in the atmosphere - not the warming we would expect from other possible causes.

    Even if scientists did discover another reasonable explanation for the warming recorded so far, that would give birth to a difficult question. As Robert Henson puts it: “If some newly discovered factor is to blame for the climate change, then why aren't carbon dioxide and the other greenhouse gases producing the warming that basic physics tells us they should be?”

    The only way to prove with 100% certainty that humans are responsible for global warming would be to run an experiment with two identical Earths-one with human influence and one without. That obviously isn't possible, and so most scientists are careful not to state human influence as an absolute certainty.

    The Healthy Habits Survey shows that only about one third of American seniors have correct habits. Here are some findings and expert advice.

    ⒈How many times did you brush your teeth yesterday?

Finding: A full 33% of seniors brush their teeth only once a day.

Step: Remove the 300 types of bacteria in your mouth each morning with a battery-operated toothbrush. Brush gently for 2 minutes, at least twice a day.

    ⒉How many times did you wash your hands or bathe yesterday?

Finding: Seniors, on average, bathe fewer than 3 days a week. And nearly 30% wash their hands only 4 times a day—half of the number doctors recommend.

Step: We touch our faces around 3,000 times a day—often inviting germs(病菌）to enter our mouth, nose, and eyes. Use toilet paper to avoid touching the door handle. And, most important, wash your hands often with running water and soap for 20 seconds.

    ⒊How often do you think about fighting germs?

    Finding: Seniors are not fighting germs as well as they should.

    Step: Be aware of germs. Do you know it is not your toilet but your kitchen sponge (海绵）that can carry more germs than anything else? To kill these germs, keep your sponge in the microwave for 10 seconds.

    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 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 huff and 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.