Wild mangoes come from the foothills of the Himalayas. They are by far the most important fruit in India, and have been cultivated there for four thousand years. The arrival of the mango tree in other parts of the world was probably due to the Portuguese who carried mangoes via Goa to Africa, from where they eventually reached the New World. Mango trees are now so well established in many tropical countries that it might appear that they have always been there.

    Like many tropical trees, the mango tree is multi-purpose product. Its wood is used in boat building, and its leaves can be fed to cattle. Most of the mango crop is consumed in the areas where it is grown, but in recent years mangoes have gained in popularity across the world as people in mild climate become increasingly eager to enjoy the delight of the fresh fruit.

    The global market for mangoes is very profitable, and mango producers are keen to make use of the fruit's growing popularity. Modern shoppers not only appreciate the fruit's high nutritional value(the mango is a good source of vitamin A and C, protein and fibre), but also expect it to look and taste perfect. Therefore producers now select only the best quality seedlings which have the most chance of developing into good quality fruit.

    Mangoes are high in fiber, thus making them very good for the heart. The high fiber content is also helps easing constipation. They have high pectin(果胶) and vitamin C content that reduces the blood cholesterol levels and serves as an immune booster. This fruit is rich in anti-oxidants, vitamins, minerals and contain an enzyme(酶) that has stomach soothing properties. These enzymes act as a digestive aid and digestive proteins.

    Although the mango tree has spread from its native Himalayan foothills to the tropics, delivering the fresh fruit to the world's supermarkets presents a challenge, as it does not travel well. Producers transport the fruit by speedy but costly air freight (货运)for minimum delay rather than risk the cheaper but slower road or shipping routes which, can result in damage to the fruit.

    Mangoes are usually in storage for some time after their arrival at their destination. The fruit must be kept cold, or the sweet, juicy flesh will soon become over ripe and the mangoes will be unfit for sale. Fortunately, extremely effective refrigeration is now available and this is the best way of preventing the fruit from going bad before it reaches the supermarket shelves.

    Binge-watching (刷剧) is when a person watches more than one episode of a TV show one after another. With developments in the speed and connectivity of the Internet, increases in technology and the rise of on-demand entertainment companies, people can now watch their favorite shows directly on the Internet at their convenience.

    This behavior is nothing new. In fact, “binge-watching” has been officially listed in dictionaries since 2015. The entertainment companies recognize this behavior and many take steps to encourage it. Often, instead of releasing each episode on a week-by-week basis, an entire series will become available at the same time. Once the episode finishes, many platforms will display pop-ups with “you might like” suggestions, or will automatically play the next episode.

    However, this wonderful gift may in fact be poisonous. Recent research from British media Ofcom suggests that this behavior may have become a hindrance (障碍). Out of the more than half of British adults who watch more than one episode of a show in a row, almost a third have admitted missing sleep or becoming tired as a result; and one quarter have failed to do their household chores. Next well be missing work!

    Bingeing has other connections—binge eating, binge drinking and binge smoking, all of which are often associated with compulsive (强迫性的) behavior, a lack of control and possible route to addiction. Lindsey Fussell, consumer group director at Ofcom, said, “The days of waiting a week for the next episode are largely gone, with people finding it hard to resist watching multiple episodes around the house or on the move.” If people find binge-watching hard to resist, coupled with the fact that it has shown to lead to negligence (疏忽) in many, are we witnessing the birth of a new type of addiction?

    The large amount of information and entertainment that television and online media can bring us is, many would say, a good thing. It offers us opportunities to better understand the world we live in, educate ourselves and enjoy much needed downtime. However, like any behavior done to an extreme degree, it can become dangerous. And when the activity begins to bleed into other areas, causing us to stop functioning-then it becomes a problem. So, what's the answer? Neither a tiny amount, nor too much. After all, as the old proverb says, a little of what you fancy does you good.

    We all know what a brain is. A doctor will tell you that the brain is the organ of the body in the head. It controls our body's functions, movements, emotions and thoughts. But a brain can mean so much more.

    A brain can also simply be a smart person. If a person is called brainy, he is smart and intelligent. If a family has many children but one of them is super smart, you could say, "He's the brains in the family." And if you are the brains behind something, you are responsible for developing or organizing something. For example, Bill Gates is the brains behind Microsoft.

    Brain trust is a group of experts who give advice. Word experts say the phrase "brain trust" became popular when Franklin D. Roosevelt first ran for president in 1932. Several professors gave him advice on social and political issues（问题）facing the U.S. These professors were called his "brain trust".

    These ways we use the word "brain" all make sense. But other ways we use the word are not so easy to understand. For example, to understand the next brain expression, you first need to know the word "drain". As a verb, to drain means to remove something by letting it flew away. So a brain drain may sound like a disease where the brain flows out the ears. But, brain drain is when a country's most educated people leave their countries to live in another. The brains are, sort of, draining out of the country.

    However, if people are responsible for a great idea, you could say they brainstormed it. Here, brainstorm is not an act of weather. It is a process of thinking creatively about a complex topic. For example, business leaders may use brainstorming to create new products, and government leaders may brainstorm to solve problems.

    If people are brainwashed, it does not mean their brains are nice and clean. To brainwash means to make some accept new beliefs by using repeated pressure in a forceful or tricky way. Keep in mind that brainwash is never used in a positive way.

    Netgear Wi-Fi Range Extender

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    Why We Love It: This is a great device to increase your wi-fi signal and get the fastest streaming power. It's also useful to set up separate wi-fi networks for guests.

    External Phone Charger

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    Why We Love It: Charge your phone anywhere while also extending its battery life. This particular model can also be used with the iPhone, Samsung Galaxy, and iPad. It has a standard USB drive so users can charge e-readers as well.

    Pop Sockets Smartphone Stand

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    Why We Love It: It may look silly, but this gripper is actually really useful for taking pictures or watching videos. It also folds down flat when not in use for a more separate look.

    Fitbit

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    Why We Love It: Track steps and monitor sleep cycles to improve your health. It also records workouts, and receives call, text, or calendar notifications.

    How was your day today? If it was just sort of OK, with nothing much happening, then Scott Shaffer wants to hear from you. Mr Shaffer is the editor of the Journal of Mundane Behaviour. "We can learn a lot about the way that society works by examining normal patterns of behavior," he says. "All the ordinary decisions we make and ordinary things we do are society in action."

    The idea that social scientists should "study the unmarked", in Mr Shaffer's words, has also spread to historians. Traditionally, most history has been written as the story of greatness. It is all about great ideas, great people and great economic and social forces changing the way that millions of people live for ever. Albert Einstein's theory of relativity changed the way that we look at the universe. But has he been of more benefit to humanity than the unknown person who invented the first really comfortable shoe? Try thinking great thoughts when your feet hurt.

    In recent years, books of micro-history have been a great success with the public. Most micro historians like to relate their subject to wider developments in society. According to historian Catherine Gallagher, the potato was once a matter of great argument. Supporters pointed out that it could grow cheaply and easily and help feed the poor. Opponents said that this would lead to the poor becoming more powerful, since they did not have to spend every hour working to feed themselves. It seems that European socialism started with an argument about vegetables. British historian Colin Jones wants us to look at pictures painted hundreds of years ago. He wants us to notice the fact that nobody smiles in these pictures. Compare that with today, when everyone smiles for the camera and refusing to smile is seen as an unfriendly act. It is all because of dentistry, he says. Once people were able to look after their teeth, they began to smile and the world became a happier place.

    Whether stories like this are true or not, they put ordinary people at the center of history. Most of us are not going to change the world in a big way. But we might be able to do something that makes life a bit easier for other people. And maybe one day a historian will come along and write the story. It is something to get excited about, though perhaps not very excited.

Earthquake rescue robots have experienced their final tests in Beijing.Their designers say with these robots，rescuers will be able to have more time to save more lives during an earthquake.

This robot，looking like a helicopter，is called the detector bot.It's about 4 meters long，and it took about 4 years to develop the model.Its main functions are to collect information from the air，and send goods of up to 30 kilos to people trapped by an earthquake.

This robot has a high－definition 360－degree panoramic(全景的) camera.It can work day and night and will also be able to send the latest pictures from the quake area.

Dr.Qi Juntong，from the Chinese Academy of Science，said，"The most important feature of this robot is that it doesn't need a distant control.We just set the destination(目的地) information on it，and then it takes off，and lands by itself.It flies as high as 3，000 meters，and as fast as 100 kilometers per hour."

This robot has a different function—it can change as the environment changes.Its main job is to search for any signs of life in places where human rescuers are unable to go.

As well as a detector(探测器) that finds victims and detects poisonous gas，a camera is placed in the 40－centimeter－long robot，which can work in the dark.

Another use for the rescuers is the supply bot.With its 10－meter－long pipe，people who are trapped in the ruins，will be able to get supplies including oxygen and liquids.

Experts have said that the robots will enter production，and serve as part of the national earthquake rescue team as soon as next year.