For centuries, elephants have played a big role in the world's economies, culture and religion. The African elephant used to be found all over Africa and the Asian elephant moved from Syria to China to Indonesia. Nowadays, elephants are found in small groups in the south of the Sahara Desert and scarcely in Southeast Asia, Sri Lanka and India.

    In the early twentieth century, there were close to ten million elephants, and now the elephant number is as low as 252,000 and expected to drop down to 160,000 by 2025. Between 2007 and 2014, the elephant population fell by at least 30%, or 144,000 elephants. As researchers have traveled over the African plains, they only spotted one herd of 36 elephants in an area like the size of Mexico. It is clear that these gentle mammals are disappearing right before our eyes.

    There are many reasons why the elephant population has been decreasing, one of which is their habitat. Humans are competing with elephants for living space, and as more and more humans clear the land that is being used by elephants, the elephants have less space. Elephant hunting or "poaching" has been a major factor for the disappearance of this species, and they are killed only for their valuable ivory tusks. Although the trade of tusks is illegal, it is still a common practice in many places.

    Often, all the local people living among elephants would be farmers, and found that they could make more money by selling the tusks of one elephant, than doing manual labor for twelve years. That alone makes it really hard to prevent them from killing the elephants.

    Some places such as Botswana, have put in extra effort to protect their wildlife from poachers by founding their Botswana Defense Force, which is made up of around 700 specially-trained soldiers that are stationed in 40 different areas. You may feel worried about the present situations elephants are in, but there are ways to help. To find out how you can help elephant conservation, adopt an elephant, or donate, click here.

    When other nine-year-old kids were playing games, she was working at a petrol station. When other teens were studying or going out, she struggled to find a place to sleep on the street. But she overcame these terrible setbacks to win a highly competitive scholarship and gain entry to Harvard University. And her amazing story has inspired a movie, “ Homeless to Harvard: The Liz Murray Story”, shown in late April.

    Liz Murray，a 22-year-old American girl, has been writing a real-life story of willpower and determination. Liz grew up in the shadow of two drug-addicted parents. There was never enough food or warm clothes in the house. Liz was the only member who had a job. Her mother had AIDS and died when Liz was just 15 years old. The effect of that loss became a turning point in her life. Connecting the environment in which she had grown up with how her mother had died, she decided to do something about it.

    Liz went back to school. She threw herself into her studies, never telling her teachers that she was homeless. At night, she lived on the streets. “ What drove me to live on had something to do with understanding, by understanding that there was a whole other way of being. I had only experienced a small part of the society,” she wrote in her book Breaking Night.

    She admitted that she used envy to drive herself on. She used the benefits that come easily to others such as a safe living environment, to encourage herself  that “next to nothing could hold me down”. She finished high school in just two years and won a full scholarship to study at Harvard University. But Liz decided to leave her top university a couple of months earlier this year in order to take care of her father, who has also developed AIDS. “I love my parents so much. They are drug addicts. But I never forget that they loved me all the time.”

    Liz wants moviegoers to come away with the idea that changing your life is “as simple as making a decision”.

    A cellphone is one of the few things that we hold close to our faces all the time, and yet it could possibly explode - this is what made the recent Samsung's Galaxy Note 7 smart-phone accidents so shocking.

   According to technology news website The Verge, flawed（有瑕疵的）phone batteries might be to blame.

    Even if you are not a science student, you probably know that it is common sense that the anode (the negative（负的）end of the battery) and the cathode (the positive end) should never touch. If they do, the battery will short-circuit（短路）, causing a powerful electrical reaction that can destroy the battery and cause a fire.

    This is why all lithium-ion（锂离子）batteries - the kind that can be found in many of our devices like tablets and cameras - have a separator layer inside to stop the two ends from touching one another.

    But somehow, the separators in some of the Samsung phones broke, causing explosions.

    Overcharging is another problem that can make batteries heat up quickly. Fortunately, most batteries are designed to be able to automatically stop charging once they are fully charged. But again, this somehow failed to happen in some of the Samsung phones.

    The two “somehows” may sound random（随机的）and hard to explain. But they actually both come from the fact that phone producers have been pushing the limits of batteries to meet customers' demand for a longer battery life.

    According to Lynden Archer, a materials scientist at Cornell University, US, we have already achieved 90 percent of the battery life possible from a lithium-ion battery. Customers' demand that their devices get thinner has also given producers little choice but to try to put more power into thinner batteries.

     “The more energy you put into a box, the more dangerous it's going to be,” Billy Wu, a lecturer at Imperial College London, told The Guardian.

    A thinner battery also means producers have to use thinner material for separators, and thinner material has more chance of breaking.

    As Internet users become more dependent on the Internet to store information, are people remember less? If you know your computer will save information, why store it in your own personal memory, your brain? Experts are wondering if the Internet is changing what we remember and how.

    In a recent study, Professor Betsy Sparrow conducted some experiments. She and her research team wanted to know the Internet is changing memory. In the first experiment, they gave people 40 unimportant facts to type into a computer. The first group of people understood that the computer would save the information. The second group understood that the computer would not save it. Later, the second group remembered the information better. People in the first group knew they could find the information again, so they did not try to remember it.

    In another experiment, the researchers gave people facts to remember, and told them where to find the information an the Internet. The information was in a specific computer folder (文件夹). Surprisingly, people later remember the folder location (位置) better than the facts. When people use the Internet, they do not remember the information. Rather, they remember how to find it. This is called “transactive memory (交互记忆)”

According to Sparrow, we are not becoming people with poor memories as a result of the Internet. Instead, computer users are developing stronger transactive memories; that is, people are learning how to organize huge quantities of information so that they are able to access it at a later date. This doesn't mean we are becoming either more or less intelligent, but there is no doubt that the way we use memory is changing.

    Humans and many other mammals have unusually efficient internal temperature regulating systems that automatically maintain stable core body temperatures in cold winters and warm summers. In addition, people have developed cultural patterns and technologies that help them adjust to extremes of temperature and humidity (湿度).

    In very cold climates, there is a constant danger of developing hypothermia, which is a life-threatening drop in core body temperature to below normal levels. The normal temperature for humans is about 37.0℃. However, differences in persons and even the time of day can cause it to be as much as 6℃ higher or lower in healthy individuals. It is also normal for core body temperature to be lower in elderly people. Hypothermia begins to occur when the core body temperature drops to 34.4℃. Below 29.4℃, the body cools more rapidly because its natural temperature regulating system usually fails. The rapid decline in core body temperature is likely to result in death. However, there have been rare cases in which people have been saved after their temperatures had dropped to 13.9-15.6℃. This happened in 1999 to a Swedish woman who was trapped under an ice sheet in freezing water for 80 minutes. She was found unconscious, not breathing, and her heart had stopped beating, yet she was eventually saved despite the fact that her temperature had dropped to 13.7℃.

    In extremely hot climates or as a result of uncontrollable infections, core body temperatures can rise to equally dangerous levels. This is hyperthermia. Life-threatening hyperthermia typically starts in humans when their temperatures rise to 40.6-41.7℃. Only a few days at this extraordinarily high temperature level is likely to result in the worsening of internal organs and death.

    Kids and science seem to be made for each other!

    The basic science is a combination of thought and experiment called the scientific method. It's where you start with an idea, create a way to prove or disprove your idea, and show what you learned based on facts. Learning to follow this process helps you think logically (逻辑地) and carefully. These important thinking skills can be used in many areas of study. To give a child practice with these thinking skills is like giving vitamins (维生素) to a developing mind.

    One of the greatest things we can teach our children is to love learning. Learning science is a great way to do so. Children are easy to be interested in science. Because much of science is hands­on, it attracts most children. Nothing makes a child sit up and take notice like the "WOW!" of a great science showing.

    Science opens doors to many subjects at school. Building love for science can be helpful in other areas of study. For example, one cannot love science for very long without becoming good at its language — math! So science encourages children to study math. An interest in science is an interest in how things were once understood compared to how they are understood now. Thus studying science lends itself easily to studying history. And after you do an experiment, you need to write a lab report. Therefore, writing becomes an important part of science.

    Science is the basic thing for much of our life. The science of farming shows how our food is produced; biomedical science keeps us healthy; even our beds these days are designed according to scientific facts. We almost eat, sleep and breathe with the help of science! When we prepare the next generation (一代) of voters, creators, and policy makers, it is important to make sure they are not only comfortable but also good at science.