It is reported that conservation groups in North America have been arguing about the benefits and dangers of wolves. Some groups believe wolves should be killed. Other people believe wolves must be protected so that they will not disappear from the wilderness(荒野).

For Killing Wolves

    In Alaska，the wolf almost disappeared a few years ago，because hunters were killing hundreds of them for sport. However, 1aws were established to protect the wolves from sportsmen and people who catch the animals for their fur．So the wolf population has greatly increased. Now there are so many wolves that they are destroying their own food supply.

    A wolf naturally eats animals in the deer family. People in the wilderness also hunt deer for food. Many of the animals have been destroyed by the very cold winters recently and by changes in the wilderness plant life．When the deer can't find enough food，they die.

    If the wolves continue to kill large numbers of deer, their prey(猎物) will disappear some day. And the wolves will, too. So we must change the cycle of life in the wilderness to balance the ecology. If we killed more wolves, we would save them and their prey from dying out. We'd also save some farm animals.

    In another northern state, wolves attack cows and chickens for food. Farmers want the government to send biologists to study the problem. They believe it necessary to kill wolves in some areas and to protect them in places where there is a small wolf population．

Against Killing Wolves

    If you had lived long ago，you would have heard many different stories about the dangerous wolf．According to most stories，hungry wolves often kill people for food．Even today，the stories of the “big bad wolf” will not disappear．

    But the fact is wolves are afraid of people, and they seldom travel in areas where there is a human smell．When wolves eat other animals，they usually kill the very young, or the sick and injured. The strongest survive. No kind of animal would have survived through the centuries if the weak members had lived. And has always been a law of nature.

    Although some people say it is good sense to kill wolves，we say it is nonsense! Researchers have found wolves and their prey living in balance．The wolves keep the deer population from becoming too large, and that keeps a balance in the wilderness plant life.

    The real problem is that the areas where wolves can live are being used by people. Even if wilderness land is not used directly for human needs, the wolves can't always find enough food. So they travel to the nearest source, which is often a farm. Then there is danger. The “big bad wolf” has arrived! And everyone knows what happens next.

    I was never very neat，while my roommate Kate was extremely organized. Each of her objects had its place，but mine always hid somewhere. She even labeled(贴标签) everything. I always looked for everything. Over time，Kate got neater and I got messier. She would push my dirty clothing over，and I would lay my books on her tidy desk. We both got tired of each other.

    War broke out one evening. Kate came into the room. Soon，I heard her screaming，“Take your shoes away！Why under my bed！” Deafened，I saw my shoes flying at me. I jumped to my feet and started yelling. She yelled back louder.

    The room was filled with anger. We could not have stayed together for a single minute but for a phone call. Kate answered it. From her end of the conversation，I could tell right away her grandma was seriously ill. When she hung up，she quickly crawled(爬) under her covers，sobbing. Obviously，that was something she should not go through alone. All of a sudden，a warm feeling of sympathy rose up in my heart.

    Slowly，I collected the pencils，took back the books，made my bed，cleaned the socks and swept the floor，even on her side. I got so into my work that I even didn't notice Kate had sat up. She was watching，her tears dried and her expression one of disbelief. Then，she reached out her hands to grasp mine. I looked up into her eyes. She smiled at me，“Thanks.”

    Kate and I stayed roommates for the rest of the year. We didn't always agree，but we learned the key to living together：giving in，cleaning up and holding on.

    No matter where you are, knowing how to protect yourself and your family during an earthquake is necessary. Here are some tips for you.

    Duck, Drop, Cover and Hold

    Duck under a strong piece of furniture, if possible. Most earthquake injuries are the result of being hit by something falling on you. Drop to the floor to avoid falling or being thrown down. And protect you from flying glass. Use clothes, blankets, cushions or furniture for covering. Hold on to whatever you're using, as the ground motion may be violent. Get away from glass, bookcases or anything heavy that could fall over on you.

    Stay away from the doors

    Doorways used to be recommended but most experts now say: stay away from them. Doors can suddenly shut with bone crushing force. Anyway, the experts say that in modern construction a doorway is no stronger than any other location along the wall.

    Try to run outside

    While the ground is moving, the greatest danger is of being injured by taking a fall or being hit by a falling piece of building as you exit. If you smell gas or when the shaking stops, calmly, carefully make your way out and get clear of the building. Before you leave, get shoes on because you will be walking on broken glass. If you're in a crowd, stay calm, and take what can cover you and find where you are. In a crowd the greatest dangers are panic and the rush for an exit.

    Donna Strickland is a professor in the Department of Physics and Astronomy. Professor Strickland is one of the recipients( 受领者) of the Nobel Prize in Physics 2018 with Gérard Mourou, her PhD supervisor at the time. They published this Nobel-winning research in 1985 when Strickland was a PhD student at the University of Rochester in New York state. Together they paved the way toward the most intense laser pulses ever created.

    Professor Donna Strickland is only the third woman ever to have won a Nobel Prize in physics. She and her fellow winners were honored for what the Nobel Committee called ground-breaking inventions in laser physics. Professor Strickland devised a way to use lasers as very precise drilling or cutting tools. Millions of eye operations are performed every year with these sharpest of laser beams.

—"How surprising do you think it is that you're the third woman to win this prize? "

—"Well, that is surprising, isn't it? I think that's the story of Maria that people want to talk about — that why should it take 60 years? There are so many women out there doing fantastic research, so why does it take so long to get recognized? "

    Physics still has one of the largest gender gaps in science. One recent study concluded that at the current rates it would be more than two centuries until there were equal numbers of senior male and female researchers in the field.

    The last woman to win a physics Nobel was German-born Maria Goeppert-Mayer for her discoveries about the nuclei of atoms. Before that it was Marie Curie, who shared the 1903 prize with her husband, Pierre. This year's winners hope that breaking this half century hiatus will mean the focus in future will be on the research, rather than the gender of the researcher.

    A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech integrated systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.

    "It's extremely important for us to think about this as a whole system and not just the sum of a bunch of individual components (元件)," said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. A few years ago, his team got the go-ahead to start piecing together the components. "The added difficulty with a project like this is that actually none of those components are off the shelf and so we have to develop them all on our own," he said.

    They engineered a series of systems to start and drive the robotic fly. "The seemingly simple system which just moves the wings has a number of interdependencies on the individual components, each of which individually has to perform well, but then has to be matched well to everything it's connected to," said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.

    While this first robotic flyer is linked to a small, off-board power source, the goal is eventually to equip it with a built-in power source, so that it might someday perform data-gathering work at rescue sites, in farmers' fields or on the battlefield. "Basically it should be able to take off, land and fly around," he said.

    Wood says the design offers a new way to study flight mechanics and control at insect-scale. Yet, the power, sensing and computation technologies on board could have much broader applications. "You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead," he said. "So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis."

    A video of a three-year-old girl being kicked by her own mother during a photo shot went viral (疯狂传播) on Thursday, indicating China's under per forma nee in regulating the emerging child modeling industry.

    The girl, known as Niu Niu, was physically abused by her mother in several videos. The videos have annoyed Chinese media and Internet users alike. Many netizens and scholars call for local authorities to carry out further investigations into possible child abuse.

    In response to the public outcry (强烈抗议), Niu Niu's mother issued an apology via Sina Wei bo on Thursday, condemning accusations of abuse. She noted that she was merely guiding her daughter for better shots and the girl is well looked after.

    Despite her apology, many E-shops which used Niu Niu's images for brand promotion have canceled their cooperation with the mother, while over 110 well-known child garment shops on Taobao have signed up for a campaign to provide better protection for child models.

    "It is necessary to adopt comprehensive laws and regulations to further protect the kids, preventing their parents and companies from exploiting (利用) them," Fang Zhiqing, a lawyer and child protection expert, said.

    Niu Niu is not alone. In Zhili, a small town in Zhejiang province, thousands of children from across China are taken here by their parents to seize the chance of fame. With a population of 450,000. Zhili has over 13,000 manufacturers of child clothing. In 2017, the town earned over 7 billion yuan by selling do thing for children online, thus providing opportunities for child models.

    "China's current advertisement law isn't workable when it comes to the industry of child modeling, as it lacks clear supervision measures and clear legal punishment." Fang added. "It is important to issue new laws which regulate child modeling."