Laughter has many health benefits and can even play a role in the treatment and prevention of illnesses. The immediate effect of laughing is a positive, joyful feeling. This is quickly followed by an increase in your heart rate, breathing rate, and oxygen consumption. Next comes a period during which your muscles relax, as your heart rate, breathing rate, and blood pressure begin to decrease. In the end, all of this leads to a significant reduction in stress.

Many years ago, golfers realized that an old ball covered in dents flies farther than a smooth one. Since then, golf balls have been made with dimples. These balls can fly nearly twice as far as smooth ones. This is because the dimples reduce drag forces, which pull on balls and slow them down. Dimples also force the flow of air downward, which pushes the ball upward. These are the same principles that allow airplanes to fly. There are no rules about how many dimples a golf ball should have, but the most common number of dimples is 392.

Almost 1 billion people around the world don't have easy access to safe drinking water. This leads to many illnesses and even death. Thankfully, South African researchers have found a solution: water-purifying tea bags. These special bags contain nano-structured fibers that act as a filter and special pieces of carbon that kill harmful bacteria. Placing these tea bags into the necks of water bottles enables you to drink fresh water without falling ill. The bags are also biodegradable and incredibly cheap to make.

Perhaps the biggest mistake that most investors make when they first begin investing is getting into a panic over losses. This is a major obstacle to making a strong and long-lasting plan. We work hard for our money, and we want to see it grow and work hard for us. But what most beginning investors don't understand is that investing in the stock market is a risk, and that with risk, you sometimes take losses. Although an investment may be falling in price, it doesn't mean you have to abandon it in a rush. The point is, as investors, we should not focus on short-term losses, but rather on long-term growth. Therefore, be patient when it comes to not only your stock portfolio but to personal investments as well.

Products that are considered green are generally preferred by consumers. However, many people who purchase these products are not actually concerned about the environment. In a survey, people who had purchased a hybrid car were asked why they chose their automobiles. "It's good for the earth" wasn't a top answer, but "It sends a message about me" was. This suggests that people sometimes engage in socially responsible behavior in order to elevate their place in society. The "costly signaling theory" may explain this. It states that people often display their high status through generous acts. These acts show that they have so much time, money, or energy that they can give it away without any problems.

Since a great deal of day-to-day academic work is boring and repetitive, you need to be well motivated to keep doing it. A mathematician sharpens her pencils, works on a proof, tries a few approaches, gets nowhere, and finishes for the day. A writer sits down at his desk, produces a few hundred words, decides they are no good, throws them in the bin, and hopes for better inspiration tomorrow. To produce something worthwhile ─ if it ever happens ─ may require years of such fruitless labor. The Nobel Prize-winning biologist Peter Medawar said that about four-fifths of his time in science was wasted, adding sadly that "nearly all scientific research leads nowhere." What kept all of these people going when things were going badly was their passion for their subject. Without such passion, they would have achieved nothing.

A behavioral science experiment was conducted in California. Signs that asked people to use fans instead of air conditioners were placed on doors in a neighborhood. There were four types of signs. The first told people how much money they could save. The second contained an environmental message, and the third asked people to be good citizens. The experiment's results showed that none of these signs had any effect on people's behavior. But there was a fourth sign that simply said: "A survey showed that 77 percent of your neighbors use fans instead of air conditioners." Unlike the other signs, this one clearly got people's attention, causing a sharp decrease in energy use. This shows that in some situations, social pressure is the best way to get people to take action.

Schadenfreude means "a feeling of pleasure at the misfortunes of others." What makes schadenfreude a complicated word is that it is a mixture of other feelings. Neuroscientists have found that jealousy, relief, and a need for approval from others are all involved. Imagine the following situation. A model student who gets perfect grades and is good-looking suddenly fails a test. As one of her classmates, you probably envy her, so you may be secretly happy to see her fail. Now imagine that you are also one of the best students in the class. Seeing a competitor facing difficulties is likely to give you a sense of relief that you're not the one who failed. You may even feel that your own performance is more acceptable, as your score seems better now that the best student has failed.

Rembrandt, the famous 17th-century Dutch artist, is known for having painted more than 100 self-portraits. These paintings reveal the changes in the way he saw himself. In his early works, he painted himself as a successful young artist. He used the same composition found in portraits of upper-class individuals at that time. For example, the painting Rembrandt and Saskia is a portrayal of him and his wife wearing expensive clothes and appearing full of happiness and pride. Later, however, the fact that he had become a sad and troubled man is clearly shown in his self-portraits. Depressed after the death of his wife, he even painted himself as a beggar. In his picture, poverty was used as a metaphor for his deep despair.

The acceleration of human migration toward the shores is a contemporary phenomenon, but the knowledge and understanding of the potential risks regarding coastal living are not. Indeed, even at a time when human-induced greenhouse-gas emissions were not exponentially altering the climate, warming the oceans, and leading to rising seas, our ancestors knew how to better listen to and respect the many movements and warnings of the seas, thus settling farther inland. For instance, along Japan's coast, hundreds of so-called tsunami stones, some more than six centuries old, were put in place to warn people not to build homes below a certain point. Over the world, moon and tides, winds, rains and hurricanes were naturally guiding humans' settlement choice.

A new spacecraft named Beresheet was launched into space with a huge amount of information, which aims to back up human knowledge and culture. This archive of data, called the "Lunar Library," is stored on 25 extremely thin nickel discs. Important historical texts and a complete English copy of Wikipedia are included in the information. The discs have a special design that allows them to hold a lot of information in a tiny amount of space. Approximately 30 million pages of information are contained in the archive despite its extremely small size. Special technology that ensures the survival of the data for billions of years was used in their making. The archive is meant to remain on the moon long into the future, preserving a copy of humanity's collected knowledge.

It is often believed that a person who has just experienced success has a greater chance of succeeding again on his or her following attempts. This, however, is not true. Usually applied to sports and gambling, this belief has become known as the "hot-hand fallacy." The primary reason for this mistaken belief is an inability to understand the concept of "statistical independence." This means that each event occurs without connection to any previous event. For example, imagine that a basketball player has made five shots in a row. Because each shot is an independent event, these successful attempts have no effect on the player's next shot. Therefore, the hot-hand fallacy leads people to form incorrect assumptions.

Most people have a specific position they prefer to sleep in. For some of us, this position is lying on our stomachs. However, sleep experts disagree about whether or not this position is good. Although some promote it as an easy way to reduce snoring, the majority agree that it is more harmful than you think. One of the most serious negative effects is that it changes the position of your spine. This can eventually lead to painful neck problems.

Although a baby's teeth start growing before the baby is born, they don't appear until the baby is about six months old. When a child turns five or six, these teeth start falling out. They fall out because adult teeth grow in their place and push them out. When the child reaches 12 or 13 years of age, they will have lost all their baby teeth and grown a full set of adult teeth.

If you can't hear well in a noisy situation, use your right ear. Each brain hemisphere has certain functions and is more closely connected to the opposite side of the body. The left hemisphere, which handles spoken language, is more closely connected to the right ear. Therefore, understanding words through the right ear is easier than understanding words through the left. So the next time you can't hear, put your right ear forward. The closer your right ear is to a speaker, the better you will be able to hear.

The technique I use to train my puppy is called behavior capture which is different from the common training method. Normally you first give an order and reward your puppy only when he follows it. In behavior capture, however, you first have to wait until your dog performs the behavior you want him to. Simply watch your puppy's activities, waiting for a particular behavior to occur; when one happens, reward him. For example, if you want to train him to lie down whenever you say, "Lie down," you just have to wait until he happens to do so. Then, as soon as your puppy lies down, you give him the order, "Lie down," and give him a treat as a reward. Once the puppy knows that there is a reward waiting, he treats the experience as a pleasant game.

Although a polar bear's skin is black and individual hairs are hollow and clear, polar bears do not appear black. This is due to luminescence, which allows sunlight to get to the skin but causes the fur to look white. The process starts when sunlight hits the fur. Some of the light energy travels into the hair, and it gets trapped there. The energy bounces around inside the hollow part of the hair and divides into more beams that travel in different directions. Every time a beam of light touches a hair, the light is caught and reflected towards other hairs. The process continues until the energy escapes the fur, emitting a whitish light, which makes the polar bear appear white.

A sociologist categorized play into four types. The first type, Agon, focuses on competition and includes games such as soccer and chess. The next is named Alea. This type of play, which includes card games and the lottery, depends on randomness to decide a winner. The third type, Mimicry, covers play that involves pretending, such as dressing up for Halloween. The last type is named Ilinx. This is play that uses rapid movement to create a pleasurable state of disorder. Examples include riding a roller coaster or simply spinning in circles. The sociologist pointed out, however, that a single type of play could be placed in different types by different people. With baseball, for example, one person might play it for the competition, while another might enjoy betting on the outcome.

The water that is embedded in our food and manufactured products is called "virtual water." For example, about 265 gallons of water is needed to produce two pounds of wheat. So, the virtual water of these two pounds of wheat is 265 gallons. Virtual water is also present in dairy products, soups, beverages, and liquid medicines. Every day, humans consume lots of virtual water and the content of virtual water varies according to products. For instance, to produce two pounds of meat requires about 5 to 10 times as much water as to produce two pounds of vegetables.

A zebra's stripes are used as camouflage to help it avoid predators. The wavy lines of these stripes blend in with those of the tall grass that grows in the areas where the zebra lives. Although its stripes are black and white and the grass is yellow and green, the zebra can hide effectively. Because lions, which are the zebra's primary predator, are colorblind, they are unable to detect a zebra standing still in a patch of tall grass. Zebra stripes are even more effective if zebras are gathered together in a herd. When individuals stand near one another, the patterns of their stripes blend together. This confuses lions, which see one large object instead of a group of individual animals. This makes it harder for them to catch their prey.

Dogs have lived with humans for a long time, and it is interesting to see how their roles have evolved. Once used as guards, they later became companions. These days they are serving even more valuable roles. Some dogs, for example, are trained to sense when people with epilepsy are going to have a seizure. When people are alerted to this, they can get help or go to the hospital. It is not fully understood how dogs sense this, but they may be able to smell changes in the chemical levels of the person's breath. Other dogs, known as diabetic alert dogs, are trained to detect dangerously high or low blood sugar levels.

Acoustic concerns in school libraries are much more important and complex today than they were in the past. Years ago, before electronic resources were such a vital part of the library environment, we had only to deal with noise produced by people. Today, the widespread use of computers, printers, and other equipment has added machine noise. People noise has also increased, because group work and instruction are essential parts of the learning process. So, the modern school library is no longer the quiet zone it once was. Yet libraries must still provide quietness for study and reading, because many of our students want a quiet study environment. Considering this need for library surroundings, it is important to design spaces where unwanted noise can be eliminated or at least kept to a minimum.

Although we are all aware of the damaging effects of climate change on the environment, new research shows that our personal health may also be at risk. According to a study, a type of bacterium called Vibrio is rapidly increasing in numbers because it prefers warm water. Vibrio is usually found in salty water near the coast. It infects people who eat raw seafood or swim with open cuts on their skin. Approximately 80,000 people in the U.S. get sick from Vibrio each year. This results in about 100 deaths annually. The number of people suffering from a Vibrio-related illness has been higher in recent years in both the U.S. and northern Europe. It is believed that rising temperatures in the Atlantic Ocean, which are caused by climate change, are to blame.

As restaurants are proud of the Michelin stars that they've received, you might think that the Michelins themselves were food critics. In fact, brothers Andre and Edouard Michelin, the men who created the Michelin Guide, owned a company that made tires. The original Michelin Guide promoted restaurants in the hope that it would encourage people to buy cars, and therefore tires, in order to visit them. It was given away for free and also included lists of mechanics and gas stations. As the guide's popularity grew, the brothers hired a team to anonymously visit restaurants as inspectors. Today, a three-star Michelin review remains one of the highest honors a restaurant can receive.