People can be addicted to(沉溺于) different things — e.g. alcohol, drug, certain foods, or even television. People who have such an addiction are compulsive(强迫的):They have a very powerful psychological（心理上的）need that they feel they must satisfy. According to psychologists, many people are compulsive spenders. They feel that they must spend money. This compulsion, like most others, is impossible to explain reasonably. For compulsive spenders who buy on credit(以赊欠方式), charge accounts are even more exciting than money. In other words, compulsive spenders feel that with credit, they can do anything. Their pleasure in spending large amounts is actually greater than the pleasure that they get from the things they buy.

    There is even a special psychology of bargain hunting. To save money, of course, most people look for sales, low prices, and discounts. Compulsive bargain hunters, however, often buy things that they don't need just because they are cheap. They want to believe that they are helping their budgets(预算), but they are really playing an exciting game. When they can buy something for less than other people, they feel that they are winning. Most people, experts claim, have two reasons for their behavior: a good reason for the things that they do and the real reason.

    It is not only scientists, of course, who understand the psychology of spending habits, but also business people. Stores, companies, and advertisers use psychology to increase business. They consider people's needs for love, power, or influence, their basic values, their beliefs and opinions, and so on in their advertising and sales methods. Psychologists often use a method called “behavior therapy(疗法)” to help individuals solve their personality problems. In the same way, they can help people who feel that they have problems with money.

    If you live in the U.S., you're probably used to throwing banana peel into the trash. But people in other countries, including India, have been taking advantages of their nutritional benefits for many years.

    While the flesh of a banana is soft and sweet, the skin is thick, hard and slightly bitter. To eat the peel, you can fry, bake, or boil it for at least 10 minutes. Also, the riper bananas get, the thinner and sweeter banana peel will become. That's because of a natural plant hormone(激素) called ethylene(乙烯) that fruits release as they ripen. Ethylene interacts with the sugars and fiber in the banana skin, changing complex sugars into simple sugars and breaking down pectin, a form of fiber in bananas that keeps them stiff. That's why the older your banana is, the flimsier(不结实的) it feels.

    The sweet flesh of a medium-sized banana contains great percentages of your daily recommended intake of various nutrients, such as:

·12% of your daily fiber, which helps with digestion and may help lower your risk of diabetes(糖尿病)

·17% of your vitamin C, which is important for your immune system as well as your growth

·20% of your vitamin B6, which aids the body's ability to turn food into energy

·12% of your potassium, which helps with the development of cells, tissues, and organs throughout the body

    If you eat the skin along with the flesh, you will get an even bigger increase in these same nutrients.

    Eating the peel is not only good for your body but also better for the earth. The average American ate 11.4 pounds of bananas in 2014. Since a medium-sized banana weighs about 0.3 pounds, that equates to about 38 bananas per person, or about 12 billion for the whole of the U.S. And since most of us throw away the peel, that also means a lot of organic waste.

    A world-famous Canadian author, Margaret Atwood, has created the world's first long-distance signing device(装置), the LongPen.

    After many tiring……from city to city, Atwood thought there must be a better way to do them . She hired some technical experts and started her own company in 2004. Together they designed the LongPen. Here's how it works: The author writes a personal message and signature on a computer tablet(手写板) using a special pen. On the receiving end, in another city, a robotic arm fitted with a regular pen signs the book. The author and fan can talk with each other via webcams(网络摄像机) and computer screens。

    Work on the LongPen began in Atwood's basement(地下室). At first, they had no idea it would be as hard as it turned out to be. The device went through several versions, including one that actually had smoke coming out of it. The investing finally completed, teat runs w ere made in Ottawa, and the LongPen was officially launched at the 2006 London Book Fair. From here , Atwood conducted two transatlantic book signings of her latest book for fans in Toronto and New York City.

    The LongPen produces a unique signature each time because it copies the movement of the author in real time. It has several other potential applications. It could increase credit card security and allow people to sign contracts from another province. The video exchange between signer and receiver can be recorded on DVD for proof when legal documents are used.

     “It's really fun”, said the owner of a bookstore, who was present for one of the test runs. “Obviously you can't shake hands with the author but there are chances for a connection that you don't get from a regular book signing..

    The response to the invention has not been all favorable. Atwood has received criticism from authors who think she is trying to end book tours. But she said, “It will be possible to go to places that you never got sent to before because the publishers couldn't  afford it.”

    In the future those who are taking care of old people may get help from the house itself.

    Over the last few years, new technology, such as the Internet, Wi-Fi and flat TV screens, has changed our homes and the way that we live. Now, another technology revolution is happening. A new project at the University of Hertfordshire wants to create a home that monitors people living in it who are elderly.

    The researchers have developed a wristband device（装置）which helps us to watch the elderly person who is wearing it. The device collects information to see if the person has fallen or has wandered away from where he or she should be.

    The assisted-living project is part of the university's wider Interhome project, which is the development of a smart house. The house remembers the habits of the person who lives there and it uses very low amounts of energy. The Interhome team hope that offering this service will help take care of the elderly. They say, "It's very important that these technologies are there to help and support and not replace any of the existing services."

    The Interhome is not just a research method. It's also a way for students from different scientific backgrounds to learn and develop technology. The university uses the latest technology to help students get experience by developing new hardware and software themselves. The team includes design, engineering and computer science students working together.

    "We are working on a smart-home project in Watford with some companies at the moment," says the project leader. "We are looking at how a smart home can provide even more services." This could help millions of old people around the world have a better and safer life in the future.

    While the start of a new school year is always exciting, this year was even more so for some elementary school students in Auckland, New Zealand. They became the world's first kids to be "taught" by a digital teacher, Will. Before you start imagining a human-like robot walking around the classroom, Will is just an avatar(化身) that turns up on the students' desktop, tablet, or smartphone screen when called.

    Thanks to a digital camera and microphone, the avatar not only responds to questions the kids may have, but also picks up non-verbal signals. For example, if a student smiles at Will, he responds by smiling back. This two-way communication not only helps draw the students' attention, but also allows the program's developers to monitor their involvement(参与) and make changes if needed.

    Vector's Chief Digital Officer, Nikhil Ravishankar, believes that Will-like avatars could be a novel way to attract the attention of the next generation. He says, "Using a digital human is a very popular method to deliver new information to people, and I have a lot of hope in this technology as a means to deliver rich and educational experience in the future." Greg Cross, the Chief Business Officer for Soul Machines, states that kids who have grown up in this digital time adapt(适应) to new technology quickly, and he hopes to develop the idea of digital humans in the area of educate further.

    The program, in place since August 2018, has been a great success so far. However, no mater how popular it becomes, Will is unlikely to replace human educators any time soon. For one, the avatar's knowledge base is severely limited. But more importantly, even the smartest digital avatars could never predict and react to all the unexpected situations that educators have to deal with on a daily basis. However, it could come in handy as a "personal teacher", providing kids with one-on-one help on the subjects or even topics.

    Have you ever been to London? Here is some hotel information for you.