People can be addicted to different things, e.g. alcohol, drugs, certain foods, or even television. People who have such an addiction are compulsive, i.e they have a very powerful psychological 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 irrational-impossible to explain reasonably. For compulsive spenders who buy on credit, 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 enormous amounts is actually greater than the pleasures 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, 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 need 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” to help individuals solve their personal problems. In the same was, they can help people who feel that they have problems with money.

It's a popular belief that a fish's memory lasts for only seven seconds. It may seem sad to think that they don't remember what they've eaten or where they've been, and they don't recognize you or any of their friends—every moment in their life would be like seeing the world for the first time.

    But don't be so quick to feel sorry for them. A new study has found that fish have a much better memory than we used to think. In fact, certain species of fish can even remember events from as long as 12 days ago.

    In the study, researchers from MacEwan University in Canada trained a kind of fish called African cichlids to go to a certain area of their tank to get food. They then waited for 12 days before putting them back in the tank again.

Researchers used computer software to monitor the fish's movements. They found that after such a long break the fish still went to the same place where they first got food. This suggested that they could remember their past experiences.

    In fact, scientists had been thinking for a long time that African cichlids might have a good memory. An earlier study showed that they behaved aggressively in front of certain fish, perhaps because they remembered their past “fights”. But until the latest findings, there was no clear evidence.

    Just as a good memory can make our lives easier, it also plays an important part when a fish is trying to survive in the wild.

    “If fish are able to remember that a certain area contains safe food, they will be able to go back to that area without putting their lives at risks,” lead researcher Trevor Hamilton told Live Science.

    For a long time, fish were placed far below chimpanzees, dolphins and mice on the list of smart animals. But this study has given scientists a new understanding of their intelligence.

    If you think American cooking means opening a package and throwing the contents into the microwave oven (微波炉)，think again. On the one hand, it's true that many Americans have cold cereal for breakfast, sandwiches for lunch and instant (方便的) dinners. From busy homemakers to working people, many Americans enjoy the convenience (方便) of fast food that can be ready to serve in 10 minutes or less. On the other hand, many Americans realize the importance of cooking skills. Parents—especially mothers'—see the importance of training their children- especially daughter's. Most Americans think that there's nothing better than a good home-cooked meal. But with cooking, as with any other skill, good results don't happen by accident.

    Probably every cook has his or her own way of cooking. But there are some basic skills that most people follow. For example, baking is a main method (方法) of preparing food in America. For that reason, Americans would find it next to impossible to live without an oven. American cooks pay special attention to the balance of foods, too. In planning a big meal they try to include meat, a few vegetables, some bread and often a dessert. They also like to make sure the meal is colorful. Having several different colors of food on the plate usually makes for a healthy meal.

    For those who need guidance in their cooking, or for those who have just run out of ideas, recipes are a great help. Recipes list all the ingredients for a dish (generally in the order used), the amount of each to use, and a description of how to put them together.

    Five million people visit Grand Canyon in the US every year. For the purpose of helping project Grand Canyon for your fellow visitors and future generations, please follow the guidelines below.

   Camping

    To project the park, camping is allowed only within permitted campgrounds. Permits are required for overnight camping at the North Rim. Advance booking can be received by mail. Please write: Information Center, P.O. Box 129, Grand Canyon, AZ 86023

    Fires

    Because of the extreme fire danger, campfires are not allowed except at Mather and Desert View campgrounds. Collection of firewood is not allowed either.

    Hiking

    Please stay on permitted paths. Otherwise you may destroy desert plants. Pack out what you pack in, so you leave no signs of your visit. It is important to keep in mind that you are in a national park where wildlife exists.

    Weather

    The weather at Grand Canyon can change very quickly. With so much rock, lightning causes a particular danger during sudden summer storms. These storms also frequently bring floods inside valleys, a danger to hikers. Watch the skies and check daily weather reports.

    Wildlife

    Do not feed park wildlife. There have been a few cases at Grand Canyon National Park where deer were purposely shot because they ate plastic bags that left them sick and weak. Hungry deer can be danger and have kicked and bitten visitors at Grand Canyon. Some other animals will also beg and bite. For your own safety and the well-being of the animals, please do not feed wildlife, no matter how gentle they may appear.

The Youngest Skier To The South Pole

    On Friday December 9th, a 16-year-old skier, Ameba Hempleman-Adams reached the South Pole with her father after skiing 97 miles and spending 17 nights on the ice. On the final day they skied 14 miles and afterwards Ameba said she felt “elated and tired" on reaching the South Pole.

    “The biggest challenges were the freezing cold and eating only dried food. The best bit has been experiencing what Dad does on expeditions(探险).It's the first time I've been on a difficult long journey with him and now I know what it's like. The trip brought me closer to Dad, but I also had to put up with his snoring(鼾声)which was terrible.', She added, “Would I do it again? I'm not sure. I'll have to think about that after a few nights' sleep! At times it's been really hard: I've got aching shoulders, and my back's been sore from pulling my sledge(雪橇), I've got blisters(水泡)on my feet from the boots and I've got a cold burn on my nose from my sunglasses. ______”.

    She said the most extraordinary part of the trip had been the breathtaking scenery and the sense of isolation in the Antarctic landscape.“ I've really missed my friends while I've been away and want to thank them for all their messages of support.”

    Friends and relatives who posted comments on Ameba's expedition website paid tribute(致敬)to her positive attitude which , they said ,would be an inspiration to others.

    Her father, David, said “Ameba has done amazing well. I'm proud of her. She showed real determination. She was tough and she pulled her sledge the whole way. It was a special experience to share those 97 miles with her.”

    Researchers have found bees can do basic mathematics, in a discovery that deepens our understanding of the relationship between brain size and brain power. Recently, A study conducted by researchers from RMIT University in Melbourne, Australia showed that bees could perform arithmetic operations like addition and subtraction (减法).

    Solving math problems requires a complex level of involving the mental management of numbers, long-term rules and short-term working memory. The finding that even the tiny brain of a honeybee can grasp basic mathematical operations has a possible effect on the future development of Artificial Intelligence, particularly in improving rapid learning.

    RMIT's Professor Adrian Dyer said numerical (数字的) operations like addition and subtraction are complex because they require two levels of processing. “You need to be able to hold the rules around adding and subtracting in your long-term memory, while mentally using skillfully a set of given numbers in your short-term memory,” Dyer said. “On top of this, our bees also used their short-term memories to solve arithmetic problems, as they learned to recognize plus or minus as abstract concepts.”

    The findings suggest that advanced numerical cognition (认知) may be found much more widely in nature among non-human animals than previously suspected.

    “If math doesn't require a massive brain, there might also be new ways for us to include interactions of both long-term rules and working memory in designs to improve rapid AI learning of new problems,” said Dyer.

    Many species can understand the difference between quantities and use this to search for food, make decisions and solve problems. But numerical cognition, such as exact number and arithmetic operations, requires a more complex level of processing.

    Previous studies have shown some primates (灵长目动物), birds, babies and even spiders can add and/or subtract. The new research, published in Science Advances, adds bees to that list.