Below is a selection from a popular science book.

    If blood is red, why are veins（静脉） blue?

    Actually, veins are not blue at all. They are more of a clear, yellowish color. Although blood looks red when it's outside the body, when it's sitting in the vein near the surface of the skin, it's more of a dark reddish purple color. At the right depth, these blood-filled veins reflect less red light than the surrounding skin, making them look blue by comparison.

    Which works harder, you heart or your brain?

    That kind of depends on whether you're busy thinking or busy exercising. Your heart works up to three times harder during exercise, and shifts enough blood over a lifetime to fill a supertanker. But in the long run, your brain probably tips it, because even when you're sitting still your brain is using twice as much energy as your heart, and it takes four to five times as much blood to feed it.

    Why do teeth fall out, and why don't they grow back in grown-ups?

    Baby (or “milk”) teeth do not last long; they fall out to make bigger room for bigger, stronger adult teeth later on. Adult teeth fall our when they become damaged, decayed and infected by bacteria. Once this second set of teeth has grown in, you're done. When they're gone, they are gone. This is because nature figures you're set for life, and what controls regrowth of your teeth switches off.

    Do old people shrink as they age?

Yes and no. Many people do get shorter as they age. But, when they do, it isn't because they're shrinking all over. They lose height as their spine（脊柱） becomes shorter and more curved due to disuse and the effect of gravity(重力). Many (but not all) men and women do lose height as they get older. Men lose and average of 3-4 cm in height as they age, while women may lose 5 cm or more. If you live to be 200 years old, would you keep shrinking till you were, like 60 cm tall, like a little boy again? No, because old people don't really shrink! It is not that they are growing backwards —- their legs, arms and backbones getting shorter. When they do get shorter, it's because the spine has shortened a little. Or, more often, become more bent and curved.

    Why does spinning make you dizzy（眩晕的）?

    Because your brain gets confused between what you're seeing and what you're feeling. The brain senses that you're spinning using special gravity-and-motion-sensing organs in your inner ear, which work together with your eyes to keep your vision balance stable. But when you suddenly stop spinning the system goes out of control, and your brain thinks you'removing while you're not.

    Where do feelings and emotions come from?

Mostly from an ancient part of the brain called the limbic system. All mammals have this brain area —- from mice to dogs, cats, and humans. So all mammals feel basic emotions like fear, pain and pleasure. But since human feelings also involve other, newer bits of the brain, we feel more complex emotions than any other animal on this planet.

    If exercise wears you out, how can it be good for you?

    Because our bodies adapt to everything we do to them. And as far as your body is concerned, it's “use it, or lose it”! It's not that exercise makes you healthy, it's more that a lack of exercise leaves your body weak and easily affected by disease

    People with an impulsive(冲动的)personality refer to those who tend to do things without considering the possible dangers or problems first. According to a new study by researchers at the University of Georgia, such people may be more likely to have food addiction. The study found that people exhibiting impulsive behavior weren't necessarily overweight, but impulsiveness was related to a direct relationship with food, and therefore, less healthy weight. Food addiction has been compared to addictive drug use. Studies have linked the dopamine (多巴胺)release that occurs after tasting delicious food to the dopamine release that happens when people consume other addictive substances.

    Impulsive behavior involves several personality traits(特点). Two of these traits, known as negative urgency and lack of perseverance, were particularly associated with food addiction and high BMI(身体质量指数)during the study. Negative urgency is characterized by the tendency to behave impulsively when experiencing negative emotions. Some people might drink alcohol or take drugs. For others, it could mean eating to feel better. Lack of perseverance is when a person has a hard time finishing hard or boring tasks. People with a lack of perseverance might have difficulty attempting to change addictive eating behavior, which could also cause obesity(肥胖). “Impulsiveness might be one reason why some people eat in an addictive way despite motivation to lose weight,” said Dr. Ashley Gearhardt, a clinical psychologist. He was involved in developing the Yale Food Addiction Scale in aid of those people. “We are theorizing that if food addiction is really a thing, then our measure, the Yale Food Addiction Scale, should be related to helping control impulsive action,” said Gearhardt.

    Clinical psychologist Dr. James MacKillop, whose lab was conducting the study, believes that therapies used to treat addictive drug behavior could help people who suffer from addictive eating habits.

    “Most of the programs for weight loss at this point focus on the most obvious things, which are clearly diet and exercise,” MacKillop said. “It seems that managing strong desires to eat would naturally fit in with the skills a person would need to eat healthily.”

    Hilversum is a medium-sized city between the major cities of Amsterdam and Utrecht in the Gooi area of North Holland, the Netherlands. Unlike most of the Netherlands, Hilversum is actually in a hilly area with the soil mostly consisting of sand. Once called the Garden of Amsterdam, it still attracts travelers to come over to cycle and walk through the surrounding forests. They visit it for a relaxing day off from the urban madness. For Dutch people, Hilversum is all about textile (纺织) and media industries, and modern architecture.

    In history, Hilversum was largely an agricultural area. Daily life was marked by farming, sheep raising and wool production. A railway link to Amsterdam in 1874 attracted rich traders from Amsterdam to Hilversum. They build themselves large villas (别墅) in the wooded surroundings of the town. One of the families moving in was the Brenninkmeijers, currently the wealthiest family of the Netherlands. They moved in after big success in the textile industry and aided a substantial textile industry in Hilversum. But the textile boom lasted only several decades. The last factory closed in the 1960s.

    The change to a media economy started in 1920, when the Nederlandse Seintoestedllen Fabriek (NSF) established a radio factory in Hiversum. Most radio stations called in the large villas in the leafy areas of the town. Television gave another push to the local economy. Hilversum became the media capital of the Netherlands, and Dutch televison stars moved into the leafy neighborhoods surrounding the town.

    In the early 1900s, modern architcts W.M. Dudok and J. Duiker placed hundreds of remarkable buildings in Hilversum. These modern architectural masterpieces (杰作) are so many that Hilversum almost feels like an open air museum. Dudok alone shaped most 20th century Hilversum and approximately 75 buildings in 1928-1931. It has wide international fame and is included in many architecture textbooks. The building has a remarkable shape and looks like a combination of “blocks”. Actually, one may start his journey of modern architecture by walking or biking the W.M. Dudok Architectural Route in Hilversum.

French lessons in France

    Whatever your level is, choosing to take French lessons in France is the best way to learn French. Place yourself in the local culture and practice your newly found skills in your free time.

    You will be taught by native (本地的) French speakers who have a love for teaching and use excellent teaching techniques. Lessons are interesting and you will speak French on the first day both inside and outside the classroom.

    Learners

    Suitable for all levels from beginners to advanced (高级的)

    Over 18 years old

    Class Schedule (课表)

    Classes start on Mondays and run throughout the summer.

    Please arrive at the school by 8:15 am on your first day for a short level test. It will help to place you in the right class.

    Classes run from Monday to Friday each week.

    Classes start at 8:45 am each day depending on your level.

    You will have 3 classes per day lasting 55 minutes each.

    You will have a short break between classes.

    Free Time and Tours

    The school offers a lot of cultural activities throughout the week. These activities can include cooking lessons, wine and cheese tasting, visits to Paris, cycling, movies and much more.

    You will have plenty of free time to explore (探索) the local area and practice your newly found language skills or just relax on this learning holiday with a difference.

    Other Information

    You should bring a small dictionary, pens and paper with you.

    Get more from your holiday, have fun, meet new people and take home a new language skill that will stay with you forever.

    Do you like eating processed meat? If you do, think twice now if you want to eat such meat for the sake of your health. Why? It's because eating processed meat can cause cancer, World Health Organization (WHO) experts said last Monday.

    Processed meat is the meat that has been preserved by salting, smoking, drying or canning. Experts from the WHO's International Agency for Research on Cancer (IARC) in Lyon, France studied 800 patients. The experts connected processed meat, such as hot dogs and bacon, with at least three kinds of cancer. A person who eats 50 grams of processed meat per day—about two pieces of bacon—increases his or her risk of bowel(肠) cancer by 18 percent.

    The IARC has included processed meat in its Group 1 list, for which there is “enough evidence” of connection with cancer. Tobacco is also on the Group 1 list.

WHO experts also say red meat, including beef, lamb and pork, is “probably” carcinogenic (致癌的) to humans. Dr. Kurt Strait is with the IARC. He said in a statement that the risk of cancer increases with the amount of meat a person eats. Health experts in some countries advised against eating large amounts of red and processed meat. But those suggestions had been centered on the increased risk of heart disease and obesity.

    However, meat industry groups protest the result of the WHO study. They say that meat is part of a balanced diet. They also say the causes of cancer are broad, and include environment and lifestyle factors.

    The WHO report cites the Global Burden of Disease project, which shows that diets high in processed meat lead to 34,000 cancer deaths per year worldwide.

    High school biology teacher Kelly Chavis knew smartphones were a problem in her class. But not even the students realized how much of a problem the devices were until Chavis did an in-class experiment.

    For one class period, students used a whiteboard to count every Snapchat, Instagram, text, call that appeared on their phones. Chavis is among a growing number of teachers, parents and health experts who believe that smartphones are now partly to blame for increasing the levels of student anxiety. "One girl, just during the one hour, got close to 150 Snapchat notifications. 150!" she said.

    Jean Twenge, a psychology professor at San Diego State University in California, said it is not a coincidence that youth mental health issues have risen with the number of phones. "This use of phones has led to a loss of sleep and face-to-face interactions necessary for their growth," she said.

    Researchers are still not sure whether phones cause student depression or depression causes phone use. But nearly 60 percent of parents said they worry about the influence of social media on their child's physical and mental health.

    Both schools and parents are starting to take steps to deal with the problem. Many public schools pay outside companies to watch students' social media activity for signs of anxiety. Other schools invite in yoga teachers and comfort dogs to help calm students.