The sound of a mosquito can mean trouble in many parts of the world. The bite of the mosquito can be deadly. The insects carry serious diseases like malaria (疟疾). It is estimated that almost 630,000 people died from malaria and malaria­related causes in 2012, and most of these cases were in African countries.

    In the United States, a group of California scientists are working to develop a more effective and less costly substance (物质) to protect people from mosquitoes. The researchers are investigating the sense of smell in mosquitoes. They found the insects use the same receptor for identifying carbon dioxide in human breath as they do for the smell of our skin. Anandasankar Ray, who is leading the investigation, says scientists tested more than a million chemical compounds (化合物) until they found a substance called Ethyl Pyruvate. He says Ethyl Pyruvate makes the mosquitoes' receptors inactive. “When we apply Ethyl Pyruvate to a human arm and offer it to hungry mosquitoes in a cage, very few of the mosquitoes are attracted to the human arm because only a few of them are able to smell it out,” said Ray.

    Genevieve Tauxe, a member of the research team, says it was not easy to find the neurons (神经元) of noble cells that recognize both the smell of human breath and skin. “With the device used to examine the mosquito, we are able to insert a very small electrode (电极) into the part of the mosquito's nose, where its smelling neurons are and where the smell is happening,” said Tauxe.

    Anandasankar Ray says a product based on Ethyl Pyruvate may cost less to produce than DEFT, the most effective chemical treatment now in use. He says DEFT is too costly for most people who live in areas affected by malaria.

    “Perhaps by finding smells that can attack other target receptors, we will be able to improve upon DEFT and finally have the next generation of insect behaviour control products,” said Ray.

    A large number of women in Western European countries wish that they were born men. The number is said as high as 60% in West Germany. “Women often wish that they had the same chance as men have, and believe it is still men's world,” said Dr James Holden, one of the scientists who did the study.

    Anne Harper has a very good job for an international oil company. She also believes in “Women' s Liberation(解放)”. “I don't wish that I were a man,” she says, “and I don't think many women do. But I do wish that people would stop looking down upon us women. At work, for example, we often do the work that men do but get paid less. There are still a lot of jobs that are usually the best ones and open only to men. If you're a man, you have a much better chance of leading an exciting life. How many women pilots are there ... or engineers or scientists?”

    Once upon a time there was a wise man that used to go to the ocean to do his writing. He had a habit of walking on the beach before he began his work.

    One day he was walking along the shore. As he looked down the beach, he saw a human figure moving like a dancer. He smiled to himself at the thought that someone would dance on the beach. So he began to walk faster to catch up.

    As he got closer, he saw that it was a young man and the young man wasn't dancing, but instead he was reaching down to the shore, picking up something and very gently throwing it into the ocean.

    As he got closer, he called out, "Good morning! What are you doing?" The young man paused, looked up and replied, "Throwing starfish into the ocean." "I guess I should have asked, why are you throwing starfish into the ocean?"

    "The sun is up and the tide is going out. And if I don't throw them in, they'll die."

    "But, young man, don't you realize that there are miles and miles of beach and starfish all along it. You can't possibly make a difference!"

    The young man listened politely. Then he bent down, picked another starfish, and threw it into the sea, past the breaking waves and said, "It made a difference for that one."

    There is something very special in each and every one of us. We have all been gifted with the ability to make a difference. And if we can know that gift, we will gain through the strength of our visions the power to shape the future.

    We must each find our starfish. And if we throw our starfish wisely and well, the world will be better.

    Nowadays, parents worry a lot because their children spend hours and hours in front of the TV screen. Because this doesn't happen to only one specific family, many experts warn us that there can be some serious effects of children watching violence on television.

    Children who become addicted(上瘾的) to TV sit down and turn on the TV as soon as they get home. Although they have lots of homework, they become absorbed in TV programs.

    Since they spend tons of time watching TV, they have less time to enjoy real life activities such as playing with friends, playing outdoor sports, or enjoying other kinds of entertainment.

    There are too many violent scenes on TV. Some experts say there are 25 acts of violence per hour on TV. In addition, there are many experiments by psychologists which show how TV violence influences children. Finally, people worry that children tend to imitate what they watch on TV and may start to behave more violently.

    What should be done? First of all, the government should regulate TV violence. It should also encourage people to invent and develop new technology which can block violent scenes from the programs children watch. For example, with a rating system(分级制度) and the V-chip, unfit scenes of violence and sex can be blocked out. Second, parents should monitor what their children watch. At the same time, they should make their children interested in real life activities. Then when the children start to spend more time playing with friends or reading books, parents can stop their monitoring.

    It is a fact that there is more violence on TV today than there was ten years ago. Moreover, violent incidents occur more frequently in real life. It's time to realize how harmful watching TV violence is, and it's time to keep our children from watching violence.

    As global temperatures rise, trees around the world are experiencing longer growing seasons, sometimes as much as three extra weeks a year. All that time helps trees grow faster. For the past 100 years, trees have been experiencing fast growth in temperate regions from Maryland to Finland, to Central Europe, where the growth rate of some trees has even sped up nearly 77% since 1870. Assuming wood is just as strong today, those gains would mean more timber(木材) for building, burning, and storing carbon captured from the atmosphere. But is wood really as dense as it used to be?

    Hans Pretzsch, a forest scientist at the Technical University of Munich in Germany, and his colleagues wanted to find an answer. They carried out a study of the forests of Central Europe. They started with 41 experimental plots in southern Germany, some of which have been continuously monitored since 1870. Pretzsch and his team took core samples from the trees—which included Norway spruce, sessile oak, European beech, and Scots pine—and analyzed the tree rings using a high-frequency probe.

    They found that in all four species, wood density has decreased by 8% to 12%, they report online in Forest Ecology and Management. “We expected a trend of the wood density like this, but not such a strong and significant decrease,” Pretzsch says. Increasing temperatures, and the faster growth they spur, probably account for some of the drop. Another factor, Pretzsch says, is more nitrogen in the soil from agricultural fertilizer(化肥) and vehicle exhaust. Previous studies have linked increased fertilizer use to decreased wood density. Above all, the study suggests that the higher temperatures—combined with pollution from auto exhaust and farms—are making wood weaker, resulting in trees that break more easily and wood that is less durable.

    “I am getting worried,” says Richard Houghton, an ecologist at the Woods Hole Research Center in Falmouth, Massachusetts, who was not part of the new study. As the density of the samples dropped, so did their carbon content, by about 50%. That means forests may suffer more damage from storms and may be less efficient at soaking up the greenhouse gas carbon dioxide (CO2) than scientists had thought, Houghton says.

    Some insects, such as butterflies and ladybugs, are quite beautiful. But, did you know that many bugs are also edible and are filled with protein?

    Aletheia Price knows this—and a lot more—about bugs. She also thinks you should try eating some. If you visit the website www.eatbug.com, you will find all kinds of information about edible insects. Most of it was written by Aletheia Price when she was fifteen years old. Aletheia started eating bugs at the age of thirteen. Before long, she found that she really enjoyed some of them. She also became interested in finding out more about which kinds of bugs could be eaten and how to cook them.

    According to Aletheia, there are at least 1,462 kinds of edible insects. (Doesn't that make you wonder who tried all of them and decided they were edible?) Some of her favorite dishes include mealworm chocolate chip cookies, ant tacos(玉米卷), and chocolate-covered crickets(蟋蟀). On her website she has recipes for insect entrees(开胃菜) and some helpful tips. For example, when preparing crickets, it is best to remove their legs before cooking, for the legs tend to get stuck in your teeth. She also offers information for anyone who wants to raise bugs for food.

    Aletheia realizes that eating bugs is not for everyone. But, if you think about it, you have to admit that eating bugs might be a good idea. There are billions and billions of bugs in this world. If we could get used to eating them, we would have plenty of food for everyone.