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    This year's winner of the Nobel Prize in Medicine is from Japan. According to his research, cells (细胞) sometimes "eat" themselves to keep healthy. In other words, cells can break down old ones and use the useful parts to make new cells, or to fight off viruses (病毒). This new finding could help scientists fight many diseases.

Small machines

    Three scientists from France, the United Kingdom and the Netherlands (荷兰) won the Nobel Prize in Chemistry for their work on small machines. How small? Well, they are a thousand times thinner than a strand (缕) of hair. We can't see them with only our eyes! This technology will open a whole new world for us. For example, we could make very small robots in the future. A doctor could put them into our body. Like policemen, the robots look for the ill parts in our body, and send the medicine right there.

Super-state

As teachers said in your physics class, most things in the world are in three states: solids (固体), liquids (液体) and gases . But at very low or high temperatures, things can turn into a strange state. For example, break down things to their smallest pieces and we get "atoms" (原子). Like Lego building blocks, atoms usually add up to become a 3-D thing, like a box. But atoms in the strange state don't. They stay together and become a flat thing, like a piece of paper.

    This is a new finding of three British-born scientists. And they won the Nobel Prize in Physics this year. They hope to use things in this strange state to make new materials.

About the Prize

    The Nobel Prize was started by Swedish inventor, Alfred Nobel in 1895. It gives prizes to great science research and the people behind it. Every year in October, the Royal Swedish Academy of Sciences decides who wins. It includes six prizes: chemistry, physics, physiology (生理学) or medicine, peace, literature (文学) and economic. This year each winner gets a medal and prize money of more than 6 million yuan.

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    Researchers have developed paper that can be printed with UV light (紫外线), free from the need for ink (油墨). People can clear the information away on the light-printable paper by heating it to 120℃and it can be reused more than 80 times.

    The research was carried out in order to reduce the effects of paper production on deforestation (滥砍滥伐). The researchers, from Shandong University in China and the University of California, Riverside, said that the secret behind the technology is a color-changing chemical. A thin coating of the chemical can be used on usual paper and turn it into a reusable, light-printable one. Heating the paper for 10 minutes can help clear the information away more quickly.

    Professor Yadong Yin, a chemistry professor at the University of California and a co-author of the study, said, "The greatest importance of our work is the development of a new technology to produce an ink-free rewritable paper that has the same feel and appearance as usual paper. Our work is believed to have great economic and environmental influences on the modem society." Paper production has a bad influence on the environment. It's the main cause of industrial pollution and paper thrown away by people makes up about 40% of landfills where waste is buried under the ground.

    It is predicted that light-printable paper will be inexpensive in the future. The printing process is also more cost-effective than the usual one as no ink is needed. Most importantly, it can be reused many times, which greatly reduces the cost.

    Scientists think that there has been life on earth for millions of years. However, we haven't found life on other planets yet. The earth is a planet and it goes around the sun. And there are seven other planets that also go around the sun. The sun and its planets are called the solar system. The solar system is a small part of the universe.

    Scientists have launched many spaceships to explore other planets in the solar system. Some spaceships have gone beyond the solar system. However, no one has discovered any life in space yet.

    Why has no one from other planets sent us a message? Have they tried to send information to us? With so many stars in space, are we alone, or is there life on other planets in space?

Some parents think childhood is just for playing, so they don't ask their children to do housework.

Other parents say, "I know it's wrong, but it's quicker to do it by myself!" But most parents believe that housework is a way of teaching kids responsibility (责任). Children learn to help, share and care about others by doing housework. Things like taking care of a pet or a baby and helping make meals are some examples of helping others.

Reasons for doing housework

★ To learn responsibility: Most people believe that doing housework is good for kids.

★ To share the workload (工作负担): Kids that help clean won't make a big mess.

★ To learn skills: Kids will learn how to cook, clean and do other things in the house.

There are benefits (益处) and challenges when you are doing housework, so start to help your parents with the housework. You will learn a lot by doing them.

There are so many ways to exercise, both alone and with friends. Team sports are one of the best ways, and there are so many of them to try! You can join a usual sport like football, and You can also take part in an unusual sport like walking basketball. 

When you join a team sport, you commit to practices and games. This means you will keep exercising because you have made a promise to the team to show up and play. And there will also be some rules you must follow. If you don't follow them, you will be out of the team. 

Team sports develop healthy competition. You can't always win, but you can certainly try your best to win! When you don't quite make it, make sure you show good sportsmanship to other players or teams when you win. And don't be sad if you lose. Just practice and try again, and there are always more chances. 

Team sports are also a lot more fun than doing something alone. You can make a lot of friends. When you join a sport team, it's certain that you will know more people. You can also learn a lot about games and other people. 

However, if you just want to exercise quietly, running and swimming are good choices.