Since 2008, hunters have illegally killed more than 3000 rhinos in South Africa. The International Union for Conservation of Nature warns that rhinos may die out by 2026. People who hunt and kill illegally are called poachers. The most effective way to watch for and prevent illegal hunting is from the air. However, piloted flights are too costly. Fortunately, some Spanish college students have invented a drone (无人机) that can observe more places than a plane.

    Arnau Garcia is an aeronautical (航空学的) engineering student at the Polytechnic Institute of Catalonia, in Spain. He says observers from the air have trouble finding poachers when they hide under the trees. Mr. Garcia and other students have worked with the drone manufacturer HEMAV to help find the hidden poachers. They make it by using the thermal camera, which is especially sensitive to body heat. Even when the poachers keep still, it can also keep track of them.

    The drone can fly in the wind up to 55 kilometers per hour. It has an autopilot system, so it memorizes the flight path. The drone also has a microphone, a video camera and a GPS system. These permit it to report accurately where a picture is taken. After each flight, the drone can bring back detailed information about where rhinos are found, the conditions of water and plants in the area, and the positions of suspected poachers.

    Experts say the drone can fly as far as 70 kilometers from the base. It means that it could quickly observe large areas for poachers. However, the same search operation would take days for human observers. Thanks to the drone, many poachers have been caught and the number of rhinos is on the increase. In addition, HEMAV has received an increasing number of orders for the drone. Even South African national park officials attempt to fill the air with drones.

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    You may like chewing gum (口香糖) after meals to stop your breath smelling bad; or your mother might use a special neutralizer (调理剂) to protect her permed hair (烫发). But have you thought about the chemical principles behind such everyday actions?

    On March 2, the Senior 3 students from the IB (International Baccalaureate, 国际文凭) classes at Beijing Huijia Private School presented their discoveries, all in fluent English. This kind of seminar is held every year to show the achievements of the IB chemistry experiment lessons offered by the school. IB is a qualification based on a common curriculum (课程) for students aged 16-18 in any country and is recognized by universities everywhere.

    "Once I saw an advertisement for xylitol (木糖醇) gum," recalled Zhang Xinju. "Suddenly an idea came to my mind: are there any chemical reactions when the xylitol is working on our teeth?"

    Zhang and his partner Bu Xuan visited several hospitals to try and find out. "Doctors know that xylitol can protect teeth, but few could explain how the chemical reactions happen," said the 17-year-old boy.

    Presenting the results of their research in English to an audience of Chinese and foreign judges was never a problem for the students.

    "Textbooks for IB students are in English, and our teachers speak in English," explained Wei Duan and Han Yu, whose research topic was "The Acid-Base Reaction (酸碱反应) in the process of Hair-Perming".

    "In Senior 1 we often referred to Chinese textbooks, but we found we could understand and express it all in English by the second year."

    Lu Jiang, the school's IB chemistry teacher and China's only IB vice-examiner, is proud that her students can apply scientific theories they learn in class to daily life.

    "You might have learned these facts from you kindergarten teachers, but few think about the theories behind them," Lu said. "This kind of practice is intended to develop the scientific thinking they will need in their future studies."

    My elder cousin Ted liked complaining almost about everything. When he faced a problem, he always chose to complain about it instead of finding a way to solve it. That was not right. Ted was healthy and had received a good education. He should and could find a good job and work hard to feed himself, but he just complained all day, drifting from one job to another. One day, I read about a farmer called Chris and told Ted about the farmer.

    Chris works hard, performs many jobs around the farm. But Chris is not exactly like other farmers. What makes him different is that he was born without arms or legs. But this has not stopped him from working hard and getting things done.

    Now, you may ask, is this possible? Like many other amazing people who have no arms or legs, Chris does not focus on what he can't do, but rather on what he can do. And he can do a lot! He drives farm vehicles and looks after crops. Once you see Chris in action, you will think there is nothing he could not do.

    Chris is a great example of a person who is making the most of his gifts. His positive attitude and courage make him a true inspiration.

    After I told Ted about Chris, he became silent. Compared with Chris, Ted was much luckier. Then luckily, I saw Ted's change.

    Do you like complaining? If you do, think about Chris. Such a man chooses to stay positive. Why don't we?

    Despite what so many people would love to believe，NASA hasn't discovered any evidence of past or present intelligent life on Mars. Therefore, when the Curiosity rover  (好奇号探测器)found something suspicious on the Red Planet's surface, they were not only surprised but also a little bit worried.

    The thin fragment (碎片)was suspicious enough to guarantee its own name, with NASA's Curiosity rover team calling it the “Pettegrove Point Foreign Object Debris，” named for where it was discovered. With no idea what it was or where it came from, the rover's handlers began to worry that it might actually be a piece of the rover itself，suggesting some unseen damage or other issue with the robot. Thankfully，those concerns seem to have been unfound.

    In a new update from NASA the object has now been identified as a natural piece of rock rather than a piece of any man-made craft or vehicle. The team analyzed the unusual object with a tool called the Chem Cam RMI. The instrument uses a laser (激光器)to sniff out the makeup of anything that is pointed at, and the results for this particular piece of debris revealed that it's actually just a very thin piece of rock.

    NASA describes the inspection: The planning day began with an interesting result from the previous plan's Chem Cam RMI analysis of a target that was referred to as “Pettegrove Point Foreign Object Debris”(PPFOD)，and supposed to be a piece of spacecraft debris fact. In fact it was found to be a very thin slice of rock, so we can all rest easy tonight. Curiosity has not begun to shed its skin!

    How this particularly thin sliver of rock got to where it is—and why it seems to be a different colour than the surrounding sand and debris—remains unexplained, but at least the rover isn't falling apart.

Smart Cameras to Help You Take Better Photos

    Google Clips

    One of the latest to launch is Google Clips. It is designed to be put somewhere in a room to take pictures by itself. It can also be attached to an object or a person's clothing.

    Google says machine learning helps the camera choose the best times and situations for taking pictures and videos. Interested buyers can join a waiting list to be informed when it is on the market.

    GoPro Hero

    GoPro also uses machine learning to power its QuikStories characteristic. This tool takes existing photos and videos and automatically creates a finished video piece, complete with music and effects.

    Snap Spectacles

    Messaging app Snapchat sells a pair of sunglasses with a built-in camera that can record short videos with the push of a button. Snap Inc. says the product, called Spectacles, is designed to "catch the moment, without taking you out of it."

    The glasses can record short video clips that can be shared with Snapchat users. Snap Inc. has started selling its Spectacles sunglasses online in the United States.

    Apple iPhone X

    Apple's new iPhone X is being launched with its new Face ID system that it says will unlock the phone just by having the user look at it. This replaces the Touch ID on previous ones that used a fingerprint to unlock the phone.

    Apple says the system works by projecting more than 30,000 dots on the face to create a kind of map. Apple says its facial recognition is even secure enough to allow payments through its Apple Pay service.

    Having a great collection of books at home doesn't really mean that you are a person who loves reading. It may be got from your father or your father's father, and it can just impress people around you with the fact that you are a person of culture.

    From my point of view, reading is very important in our daily life. For example, reading is a way of gaining knowledge in different areas. It can help us have a great imagination, and it makes things easier when it comes to making compositions on different themes. It gives you the possibility to speak about science, even if you don't work in this field. You can express your opinions about a political event because you have read something about that.

    Secondly, reading gives us the possibility to enter the world of imagination. We can imagine what life will be like in the future. Sometimes, we compare ourselves with the people in the stories we read and they can give us some clues to solve the problems and tell us what to do in certain situations. Books are based on real life. Even if writers are considered to be somehow different from common people, they often face the same problems as we all do.

    In short, I would like to say that literature is the perfect way of enriching our culture, expressing correctly, having a rich vocabulary, being able to understand different fields and really being considered to be a learned person.