There is a popular belief that goldfish only have a three-second memory. But a 15-year-old schoolboy from Adelaide has just finished an experiment（实验）to tell us that it is not true. He shows everybody that the goldfish is smarter than we think.

    “I don't believe that they had a three-second memory because animals need their memory, so they build up over time a knowledge of where the food is,” said Roy Stokes, a student at the Australian Science and Mathematics School.

    He did the experiment in small tank（鱼缸）of goldfish. “I decided to get a bit of red Logo and just feed them next to that. Every day I'd put it in and spread food around it.” He said.

    “At first they were a bit scared of it, but by the end of the three weeks, they were actually almost coming before I put the food in.”

    After leaving the fish alone for a week, Rory placed the red Logo block in the tank again.

    “They remembered perfectly well,” he said.

    “They actually had a time faster than the average of the three feeds before I left.”

    The goldfish showed that not only could they store information, they also had the ability to get it back as a later date.

    Culum Brown, a research fellow at Sydney's Macquarie University, has studied fish behavior for more than ten years.

    He says his studies of Australian native fish show fish were intelligent creatures that know how to avoid enemies and catch food like any other animal.

    “The thing that I really liked about Rory's experiment is he not only got that classical conditioning going but the fact that he could get them next just to that specific coloured market. I thought it was really good.” He said.

D

    When a computer works on a group of programs, it can get very hot. Cooling the computer can cost a lot. So some scientists wonder what would happen if the heat from the computer could be used.

    Large Internet companies (公司）such as Google and Microsoft have thousands of computers. As these computers deal with information, they produce lots of heat, so they need huge cooling systems(系统）. These systems send the heat into the air.

    A company in Holland(荷兰） thinks paying to make the computers work and then paying again to cool them are a waste of energy. So the company developed a special device—the e-Radiator.

    Boaz Leupe, head of the company, says the e-Radiator works as a heating system and saves money. He explains that the energy is used twice—once to heat the home and once to cool the computer and that the users don't have to pay to cool their computers.

    Five homeowners in Holland are testing the heating system in their homes.

    "We pay for the computer using, so, in that way, homeowners get heating for free," Boaz says.

    Jan Visser is one of the homeowners. "If you use the computer more, the e-Radiator produces more heat," he says. "It can't provide enough heat if you don't use your computer often." But he is ready to try it. It's a great help for his family.

    The company says e-Radiators produce heat temperatures of up to 55℃. It says the system could save its users about $440 a year.

    Smartphone apps certainly make our lives easily. However, sometimes they can also cause problems.

    Recently, the Ministry of Education(教育部) announced that teacher should not use Wechat or QQ to give homework or ask parents to grade kids's homework.

    Many teachers in China depend heavily on apps to give homework. The kids have to do their homework, stare at a phone screen. For example, Liu Yanming, a sixth-grade student in Shanghai, usually has to use his mother mobile phone to do his homework. Liu Yong, his father is afraid that apps could distract kids by encourage them to watch something unrelated(无关) to homework. "He is just 12 years old, and I do not want to buy him a cellphone," Liu told China Daily. "I also worry that my son's eyesight will be hurt because of staring at the phone for too long."

    However, Bai Yueping, president of Shanghai Tangzhen Middle School, defended (辩护) using apps for homework. Parents can understand their kids' learning situation and supervise (监督) them to finish the homework, Bai told China Daily.

    Zhang Siqi is a student from Renmin University of China.       "The use of WeChat or QQ to give homework is convenient," Zhang told China Daily. "We're living in an Internet era （时代）. It's unwise to refuse to take advantage of technology."

    Chu Zhaohui, a researcher at the National Institute of Education Sciences, believed that it is impossible to stop the use of electronic devices(设备) in the Internet era. However, students should use them when it's necessary, such as when they do listening exercises. "We don't want to stop outline education models, but they must be used carefully. Modern technologies are good... but they should not steal the show(喧宾夺主) ," he told China Daily.

    Every year on April 22, People all over the world celebrate Earth Day. It is a time to work to keep our earth clean. People plan projects to clean up the land, air and water.

    U.S. Senator Gaylord Nelson first thought of the idea for Earth Day in 1962 when he saw polluted rivers and cities with smoke. He needed to get support from Americans to clean up the earth. Finally, on April 22, 1970, 20 million Americans celebrated the first Earth Day! Now many countries around the world celebrate it, and you can, too.

    How can you celebrate Earth Day? Here are a few ideas:

    Join a clean-up project-Clean up your street or a favorite beach.

    Save energy-Turn off the lights when you leave a room, and use public transportation.

    Use less water.

    Reduce(减少)/ Reuse/ Recycle ― Practice the three Rs: First, reduce how much you use. Then reuse or recycle what you can.

    You can make a difference on Earth Day and every day!

    It took 13 years of international effort to map the human biological blueprint of all the genes (基因) that make us different people. The first rough draft (草图) made in 2000. The last of our 23 chromosomes (染色体) was clearly described in 2006. Ever since then, the age of personal genetic testing has been upon us. Since that time, a growing number of private companies have come on the market mostly through the Internet, offering to scan your personal DNA and compare it to some disease markets of the blueprint, called DTC genetic tests.

    But over the last five years the medical world has been discussing excitedly about whether these DTC tests are helpful or harmful, scientifically believable or completely useless. One of the usual criticisms (批评) is that the science is so new that no one really knows yet how to explain the information.

    "At present they largely remain in the period of research studies," notes Dr. Greg Ferro, special advisor to the director of genomic medicine at the US National Human Genome Research Institute. Ferro says there are two reasons." The first is that when they offer a test, are they really checking what they should check? And then the next is that even if it is believable, does what the test is checking really mean anything to your health?"

    Other worries include the privacy of the results and how your personal genetic information might be used by insurance (保险) companies to refuse your insurance or your boss to dismiss you. Or you could learn information with a huge social or personal impact (冲击), such as finding out that genetically you cannot possibly be the father of your child. It can also give you risks that may break your life, such as whether you are at high risk of cancer, Parkinson or other terrible diseases.

    Criticisms over the tests are such that some countries, such as Germany, have banned them. In 2011, some scientists advised the US government that most tests should be done under the guidance of medical professionals (专家). The UK government also expressed its worries about DTC genetic tests and in August 2010 made a set of rules to guide the development of genetic tests.

    In 2011, three medical researchers published a review article in the International Journal of Clinical Practice, saying that such tests offered more risks than benefits. The most important reason is that the tests might create worries or unreal results or drive unnecessary medical treatments. They also noted some of the genetic information the tests are based on at present is far from being perfect.