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Books                                  Contents
Leo the Snow Leopard By Craig Hatkoff	It was written by the best story-teller. The  story is about Leo, a young snow leopard(雪豹) that was helped by a kind man in the snowy mountains in Pakistan. Snow leopards are in danger. Leo was just two months old when he was found and he could not live in the wild on his  own.
Where Do Recyclable Materials Go By Sabbithry Persad	Tiana has been learning about recycling at  school. But after her dog, Bubbles, gets lost chasing after a recycling truck, she decides to learn  a lot more about recycling! Following Tiana, readers will learn how to take care of the environment.
The Scrap Kins Build By Brian Yanish	Meet the Scrap Kins. They are friendly monsters. In the book, they'll show you how to turn rubbish into some pretty cool things. Readers will learn how to make toy planes from plates, bags, old clothes and more. You know what they say: One person's rubbish is another person's love.
Explore( 探索) Life Cycles! By Kathleen M. Reilly	Do you know the largest seed( 种子)in the world or an egg can weigh up to 4 pounds? You'll learn about all of these things and more with the latest book in the Explore Your World series( 系列). The books give readers a good look into the life cycles of plants and animals on the Earth.

    A city without cars would be very strange, right? But Venice is such a city.

    Venice is in the northeast of Italy. It wasn't built on land, like Beijing or Shanghai, but on more than 110 islands. Seawater is everywhere around the city.

    Even so, travel isn't difficult. The waterways have always been the best way to get around. There are 117 waterways and more than 400 bridges that can guide you where you want to go.  People in Venice move from place to place by boat.

    Water makes the city special, but it is also a big problem. Sometimes tourists will have such strange experiences. One moment they walk across the Rialto Bridge, and there's nothing special. But when they come back to the bridge an hour later, it's underwater and everyone is wearing rain shoes.

    Once, people used too much underground water. This made the city get lower little by little. Now the city has gone down by 23 centimeters. Another problem is the rising seawater. The temperature has risen over the years. This has made the ice of the Arctic Ocean (北冰洋) melt( 融化). Every year, high waters hit the city in autumn and winter. When a lot of water comes, more than half of the city is underwater.

    Scientists are trying different ways to stop the city from getting even lower. The Italian government has asked some of Italy's biggest companies to build the MOST project, which was planned to be build under the seawater to stop the rising water. Anyway, this project is helping solve the problem.

    Why don't birds get lost on their long flights (飞行) from one place to another? Scientists have studied this puzzle for a long time. Now they're starting to fill in the blanks(空白).

    Not long ago, experiments showed that birds use the sun to guide them during daylight hours. How do birds fly at night? Tests with artificial stars, which are made by people, have proved that certain night-flying birds are able to follow the stars in their long-distance flights.

    They found a bird that spent its lifetime in a cage and never flew under a natural sky. But it was born with the ability to use the stars to look for the direction. This bird's cage was placed under the sky filled with artificial stars. Any change in the position of the artificial stars caused a change in the direction of the bird's flight. From the experiment, they found that the bird tried to fly in the same direction as those artificial stars moving under the natural sky.

    But the stars are of course birds' main ways of navigation (航行), when the stars are hidden by clouds, they can still find their way by such landmarks (路标) as river courses, mountain ranges (山脉), coast lines and so on. Because of this ability, people use the dove (鸽子) to send messages in some fields. For example, the doves were used to send messages in both World War I and World War II. During that time, thousands of doves were used to carry important messages in order to save the lives of many thousands of people. So it is also the symbol of peace.

    But when it's too dark to see these things, the doves are not able to find their way. They only circle helplessly and get lost.

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    Sitting too much is now listed with smoking and junk food as a bad habit that increases your risk of heart disease.

    New Australian research shows that half-an-hour in the gym will not make up for the waist-expanding damage caused by spending the rest of the day sitting.

    But the good news is that doing chores(家务杂事) in the house or gently walking around the office while on the phone might be enough to keep you fit.

    The study joins the growing body of evidence suggesting too much sitting might undo the benefits of exercise.

    The study measured the intensity(强度)of physical activities in 168 subjects over seven days. If found that, regardless of how much exercise they did or their total sitting time, those who took more breaks from sitting had lower risk of thick waists and lower levels of blood lipids(脂质).

    “Higher levels of blood lipids have been linked to a heightened risk of heart disease,”principal researcher Genevieve Healy of the University of Queensland said. "What the study shows is that there are benefits in just getting up regularly and interrupting your sitting time."

    Researchers behind the Stand up Australia project have written to the Rudd Government requesting $ 3.5 million for a two year study into how long sitting affects the health and productivity of workers.

    The latest study builds on work that is shifting the health promotion focus from purposeful exercise, such as running, to lower intensity activities throughout the day.

    The Australian research bas been backed up US studies, which show standing up is enough to double the metabolic(新陈代谢) rate and the amount of calories burnt.

    “To hold a body that weighs 77kilograms upright take a .fair amount of energy from muscles", said professor Marc Hamilton from the University of Missouri. "There is a large amount of energy associated with standing every day that cannot be easily replaced by, 30 to 60minutes in the gym."

    As space science develops, man has learned more and more about space. Space is not only amazing but also dangerous. While working in space, spacemen are facing danger.

    Scientists have found out that radiation(辐射) is the greatest danger to spacemen in space. When spacemen are working in space, they are in danger of radiation from the sun and other stars, which is bad for their health. Some special medicine may work a little, but there's no really helpful medicine.

    Space junk is also thought a great danger to spacemen. It's reported that there are 9,000 man-made things flying in space. About 30% of these are man-made satellites(卫星),10% are spaceships, and the rest are space junk. An explosion(爆炸) in 1996 made a cloud of 300,000 fragments(碎片), each at least 4 mm in size, and even a small piece of these knocked against a spaceship window and did some damage. Scientists are working on helpful ways to do with space junk.

    Although space is really dangerous, it interests everyone on the earth. In the near future, it may become usual for people to spend a few days in a space hotel. We may even choose to leave the earth and live in space for a few years. So we should care for space and do something to help improve the space environment.