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.

Top attractions

    Amsterdam is most famous for its artistic heritage. This tradition is proudly on display in the Rijksmuseum (translates as State Museum). Once you've taken in all that has to offer, artists, history fans, and families shouldn't pass up the chance to visit the Van Gogh Museum-containing around 700 paintings and drawings by Vincent and his contemporaries, including Gauguin, Monet, and Toulouse-Lautrec.

    Amsterdam is also home to the Anne Frank Museum, where Anne hid with her family during the Nazi occupation of the Netherlands. On a lighter note, taking a canal cruise through its extensive waterways is a rewarding way to see the Dutch capital.

    Art lovers get their kicks at:

     The Van Gogh Museum Rijksmuseum Museum het Rembrandthuis

    Food and drink

    Cheese lovers love Amsterdam. You can find an excuse to eat cheese at any time of the day here. Gouda is Holland's favorite, developing a more intense flavor the longer it's aged. Find a selection at the markets, try a cheeseboard at dinner time, or just order cubes with mustard for dipping to accompany a drink.

    When you're hungry for non-cheese food groups, you'll find Michelin-starred restaurants, vegetarian, and organic restaurants that accompany an array of global cuisine. For old-fashioned and modern Dutch food, try these Amsterdam restaurants: Moeders, Haesje Claes, Loetje, Greetje, and De Silveren Spiegel.

    Don't leave without tasting:

     Patat (hot chips with toppings) Stroopwafel (waffle cookie) Chocomel (chocolate milk)

    Amsterdam Fast Facts

    Approximate flight times:

     NYC/Newark 7 hours, 20 minutes Philadelphia 8 hours Boston 7 hours

     Miami 9 hours, 45 minutes Los Angeles 10 hours, 15 minutes

    Entry requirements: Passport must be valid for at least 3 months beyond your planned departure from the Schengen area and have 2 blank pages for entry stamp.

    Feifei, an 11-year-old boy from Xuzhou, Jiangsu Province, suffered from a sudden acute eye disease which has almost led to blindness. The disease was caused when he overused his eyes during the winter vacation, during which he played computer games for continuous 10 days and nights.

    Many youngsters in China nowadays are increasingly addicted to computer games and other electronic products. This is followed by a series of health problems, with the most typical case being myopia, or nearsightedness.

    According to the latest research report released by the World Health Organization (WHO),the myopia rate among Chinese teenagers ranks first in the world—70 percent of high school and college students. The rate is nearly 40 percent in primary school students, while it is only 10 percent for their peers in the United States.

    There are at least 10 million people in China with severe myopia, and they are likely to get pathological myopia（病理性的近视） in middle age. Pathological myopia can't be treated with glasses or surgery, and it is one of the biggest factors that lead to blindness, Xu Xun, an expert at Shanghai General Hospital, pointed out.

    Experts explain that two major factors lead to the high rate of myopia among Chinese people. One is high academic pressure, and the other one is excessive use of electronic devices over a long period of time. Genetics, on the other hand, are not the main reason, as only 20 percent of Chinese people had myopia in the 1960s.

    "Teenagers are now faced with severe academic pressure, which means they often study without natural light. This increases their risk of becoming nearsighted," Xu said. Experts suggest that youngsters maintain a proper balance between study and rest so as to protect their eyesight, and parents should play an active role in the process.

    When my sister Mertie told me she had put out tomato plants last summer, I was quite impressed.

    Since she was a garden-beginner, Mertie researched exactly how far apart to space her tomato plants; what kind of fertilizer to use; how to keep away the bugs, etc. Once they were planted, she took care of them daily, anxiously awaiting the juicy tomatoes to appear. But, day after day, her plants were tomato-less while all of her neighbors who had also put out tomato plants were already enjoying the fruit of their labor.

    Frustrated, Mertie gave in and went to the market to search fresh tomatoes. While paying, Mertie told the farmer her troubles. The farmer paused to think for a moment and then asked, "Well, what kind of tomatoes did you plant?"

    "I think they were called Big Boy," Mertie remembered.

    "Well there's your problem," the farmer explained. "Big Boy and Better Boy tomatoes have a 95-day growing period whereas regular tomato plants produce fruit in as few as 70 days…you just have to wait a little longer for the Big Boys."

    With that new knowledge, Mertie went home with excitement, knowing they would be worth the wait.

    Thinking about my sister's gardening experience, I had to smile. She just didn't know that Big Boy tomatoes took longer--neither did I — but once she discovered that information, she was no longer discouraged and upset about the lack of tomatoes on her plants. Instead, she was encouraged and excited to see them a few weeks later.

    It makes me wonder how many of us have "Big Boy" dreams in our hearts, yet we just don't realize that they are of the "Big Boy" variety so we are discouraged and worn out with the waiting process. Instead of waiting with excitement, we give up on our dreams and figure we must have done something wrong to stop them from coming to pass. Frustrated, we see other people's dreams coming true, and we wonder why ours haven't yet been achieved.

    The new president of Harvard University is the son of an Eastern European refugee and Auschwitz (奥斯威辛) survivor—Lawrence S. Bacow. His father worked full time while attending a state college in Detroit at night to earn his degree.

    Bacow, the former president of Tufts University, has taken over Harvard at a time when higher education is under attack for being financially out of reach to many Americans. But Bacow said his family's journey had reflected the power of college education to transform generations and the opportunities that have historically been available in the United States.

    "My parents came to this country with almost nothing," Bacow said. "I wouldn't be here if this country had not been open to people like my parents at that time. Nor would I if my father hadn't had the opportunity to get the college education."

    Bacow grew up in Pontiac, Michigan. His father's family fled anti-Jewish (反犹太的) violence in Minsk, then part of the Soviet Union, before the start of World War II and went to the United States. His mother arrived in Brooklyn at age 19, having survived Auschwitz concentration camp. She was the only Jew from her town to have survived the war. Yet Bacow, who is married with two sons, said that while growing up in Michigan, he had a happy childhood, entering science fairs as a child and building radios like his dad.

    Bacow has spent most of his professional career at MIT, Harvard and Tufts. He was a professor of environmental studies at MIT, and later a principal at the university. He led Tufts from 2001 to 2011. At Tufts, Bacow earned a reputation for shaking up a sleepy university that was being overshadowed by its peers in Boston. He is also credited with leading it through both 9/11 and the 2008 financial crisis.

    As the Tufts president, Bacow traveled around the country, reaching out to alumni (校友), and he urged his faculty and deans to do the same, in an effort to boost donations to finance Tufts' academic ambitions. He raised more than $20 million for faculty recruitment, attracting up-and-coming professors by offering junior faculty perks (福利), such as long academic leaves that they couldn't get elsewhere.

    Under Bacow's leadership, Tufts spent millions on labs and libraries. He also made addresses nationally about the need to make higher education more accessible and affordable to low-income students.

A lunar crystal (水晶) was found in lunar basalt particles (玄武岩颗粒) collected from the moon in 2020 when the Chinese moon mission landed in Oceanus Procellarum, returning with more than 1.7 kg of lunar samples delivered safely to the Earth. 

The crystal found on the near side of the moon is giving scientists hope of providing limitless power for the world forever. It is made of material previously unknown to the scientific community and contains a key ingredient for the nuclear fusion (核聚变) process, a form of power generation that uses the same forces that fuel the sun and other stars. It is transparent and roughly the width of a single human hair, and it formed in a region of the moon where volcanoes were active around 1.2 billion years ago. 

One of the primary ingredients found in this crystal is helium-3 (氦-3) , which scientists believe may provide a stable fuel source for nuclear fusion reactors. The element is incredibly rare on the Earth, but it seems to be fairly common on the moon. China's next moon mission is expected to be carried out by Chang'e 6 in 2024, which will attempt to collect the first samples from the far side of the moon, which never faces the Earth. 

Although it is too early for scientists to have made financial estimates on such a fuel source, it will undoubtedly be extremely costly. There is, of course, the matter of bringing the crystals back from the moon, especially in large amounts that are needed to fuel fusion reactors. 

Helium-3 produces significantly less radiation and nuclear waste than other elements. The current nuclear fusion process has raised serious safety concerns, and as a result, scientists have been searching for a way to create nuclear power from nuclear fusion. During the fusion process, radioactive waste is not produced, potentially making a securer and more efficient fuel source. 

Around 25 tons of helium-3 could power the US for a year. Multiple private companies and countries with space agencies have signaled their intentions to mine the moon for helium-3, and this latest discovery could kick start the race.