Everyone loves a hot shower, except maybe your skin and hair. As it turns out, hot water dries out skin and leaves hair dry and easily broken, Sejal Shah, MD (Doctor of Medicine) in New York City, told Women's Health. And if you dye (染)your hair, the color is likely to fade faster once the water gets steamy. To make matters worse, by making your skin lose natural oils, hot showers—above 99 degrees Fahrenheit—may bring about health problems. You may not like it, but the showers temperature that offers the greatest hair and skincare benefits is, well, cold.

Cold showers “strengthen the contractile fibers around pores(毛孔), muscles, and hairs which improves the firmness of skin,” says Carl Thornfeldt, MD with over 30 years of skin research experience. Though many people believe hot showers open and clear pores, it's actually wiser to close them. “Closing pores helps keep pollution from getting into the skin, at least temporarily,”

The benefits of cold showers are numerous, but surely we can't be expected to stand under cold water shivering every day especially in winter--not to mention that too cold (below the body's average temperature of 96.6 degrees Fahrenheit) is also bad. Fortunately, Dr. Thornfeldt recommends a happy medium. “The best solution is to take a warm, not too hot shower and then finish off with cold water for the last few seconds to still gain the rewards of the cold water,” he says.

That doesn't sound too unbearable. Considering the fact that our beloved, steamy showers may cause so much damage to skin and hair, it's best to switch to slightly warm temperatures to avoid losing natural oils and drying out, especially in winter when indoor heat is already sucking moisture(水分) out of skin. So, when the main part of an extremely comfortable warm shower is complete, finish off with a cool splash. Your hair and skin will thank you!

    Feifei, an 11-year-old boy from Xuzhou, Jiangsu Province, suffered from a sudden acute eye disease which has almost led to blindness. The disease was caused by excessive(过度的)eye fatigue(疲劳)during the winter vacation, during which he played computer games for continuous 10 days and nights.

    Many youngsters in China nowadays are increasingly addicted to computer games and other electronic products. This is followed by a series of health problems, with the most typical case being myopia, or nearsightedness.

    According to the latest research report released by the World Health Organization (WHO), the myopia   rate among Chinese teenagers ranks first in the world—70 percent of high school and college students. The rate is nearly 40 percent in primary school students, while it is only 10 percent for their peers in the United States.

    There are at least 10 million people in China with severe myopia, and they are likely to get pathological(病理性的)myopia in middle age. Pathological myopia can't be treated with glasses or surgery, and it is one of the biggest factors that lead to blindness, Xu Xun, director of the ophthalmology(眼科学) department at Shanghai General Hospital, pointed out.

    Experts explain that two major factors lead to the high rate of myopia among Chinese people. One is high academic pressure, and the other one is excessive use of electronic devices over a long period of time. Genetics, on the other hand, are not the main reason, as only 20 percent of Chinese people had myopia in the 1960s.

    "Teenagers are now faced with severe academic pressure, which means they often study without natural light. This increases their risk of becoming nearsighted," Xu said.

    Experts suggest that youngsters maintain a proper balance between study and rest so as to protect their eyesight, and parents should play an active role in the process.

    It's nice being nice to others; it's also great to give people a hand. However, if you start to hurt yourself by doing so, then this is not so healthy.{#blank#}1{#/blank#}If you fear that you might fall into this category, the following tips will help you to stand up for yourself and regain your self-confidence.

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    Although you may often stay silent if something is wrong or bothers you, it is better to speak your mind right away. You don't have to be rude, but you do have to be firm and direct. Don't do things for others if you don't really want to. Speak up, and soon others will be seeing you in a whole new light.

    Start small.

    {#blank#}3{#/blank#}This will allow you to practice being brave and self-confident. Tell a person who has cut in line in front of you to move to the back of the line, or tell a salesperson to do that. Before long, you will be confident enough to stand up to your friends and family members.

    Judge well.

    When dealing with others, you have to exercise good judgment. {#blank#}4{#/blank#}If a colleague isn't doing his part, you should rightfully demand that he start doing so. However, if a taxi cuts you off in traffic, just let it go.

    {#blank#}5{#/blank#}Rome wasn't built in a day. If you want to get back again after having been a pushover(耳软心活的人), it's best to take one step at a time.

A. Express yourself.

B. Regain your confidence.

C. Start by speaking up for yourself with strangers.

D. Everyone has the right to live without being judged.

E. If you slip back into the pushover mode every once in a while, don't blame yourself.

F. Sadly, some people are so easily pushed around that they come to be seen as pushovers.

G. It's one thing to be confident, but quite another to forcefully say no to an unreasonable request.

    I have never forgotten the firm belief I had in the arrival through the chimney (烟囱) of the little Santa Claus (圣诞老人), the kind, white-bearded old man who at midnight left in my tiny shoe a present I found the next morning.

    Midnight! It's the perfect hour children don't know. What great efforts I made not to go to sleep before the little old man appeared!

    I had both a great desire and great fear of seeing him, but could never stay awake until then, and the next day my first look was for my shoe. He never failed to carefully wrap (包装) every present for me. I would run barefoot to get my treasure. It never was a very expensive present, for we were not rich. It was a cookie, an orange, or very simply a fine red apple. But it felt so precious that I barely dared to eat it. What a great role imagination plays in a child's life!

    I do not at all agree with the idea that the lies about Santa Claus should be stopped. Doubts and truth come all too soon on their own. I very well remember the first year, when I was five or six, I doubted that it was not Santa Claus who put the cookie in my shoe. Since then, it has never tasted as good as the first few years of my life.

    I noted that my son believed in him longer; boys are more naïve (天真的) than little girls. Like me, he made great efforts to stay awake until midnight. Like me, he loved the cookie baked in Heaven's kitchens. And like me, the first year of his doubts was the last year of the visit of the good old man.

    In a natural disaster: a hurricane, flood, volcanic eruption, or other catastrophes. Minutes and even seconds of warning can make the difference between life and death. Because of this, scientists are working to use the latest technological advances to predict when and where disasters will happen. They are also studying how best to analyze and communicate this information once it is obtained.

    On September 29,1998, Hurricane Georges made landfall in Biloxi, Mississippi, after damaging Haiti, the Dominican Republic, Puerto Rico, and several islands of the Caribbean badly with heavy rains and winds up to 160 km per hour. Few people lost their lives along the Gulf Coast of the United States, although hundreds died in the Caribbean. This was a very different result, when a powerful Gulf Coast hurricane made an unexpected direct hit on Galveston, Texas, killing at least 6,000 people. Vastly improved hurricane warnings explain the different circumstances at either end of the 20th century—residents of Galveston had no advance warning that a storm was approaching, while residents of Biloxi had been warned days in advance, allowing for extensive safety precautions (预防).

    At the same time that people in Biloxi were thankful for the advance warning, some residents of New Orleans, Louisiana were less satisfied. A day before Georges made landfall, forecasters were predicting that the hurricane had a good chance of striking New Orleans. Emergency management officials must begin evacuations (疏散) well before a storm strikes. But evacuation costs money. The mayor of New Orleans estimated that his city's preparations for Georges cost more than 50 million. After Georges missed New Orleans, some residents questioned the value of the hurricane forecasts in the face of such high costs.

    The different views on the early warnings for Hurricane Georges show some of the complexities (复杂) related to predicting disasters. Disaster prediction is a process of providing scientific information to the government officials and other decision makers who must respond to those predictions.

    When one tried to unify gravity with quantum mechanics (量子力学), one had to introduce the idea of 'imaginary' time. If one can go forward in imaginary time, one ought to be able to turn round and go backward. This means that there can be no important difference between the forward and backward directions of imaginary time. Yet there is a big difference between the forward and backward directions of 'real time' in ordinary life. Imagine a cup of water falling off a table and breaking into pieces on the floor. If you take a film of this, you can easily tell whether it is being run forward or backward. You can tell that the film is being run backward because this kind of behavior is never observed in ordinary life.

    The explanation that is usually given as to why we don't see broken cups gathering themselves together off the floor and jumping back onto the table is that it is forbidden by the second law of thermodynamics (热力学). This says that in any closed system disorder, or entropy (熵), always increases with time. In other words, it is a form of Murphy's law: things always tend to go wrong! An intact cup on the table is a state of high order, but a broken cup on the floor is a disordered state. One can go readily from the cup on the table in the past to the broken cup on the floor in the future, but not the other way round.

    The increase of disorder or entropy with time is one example of what is called an arrow of time, something that tells the past from the future, giving a direction to time. There are at least three different arrows of time. First, there is the thermodynamic arrow of time, the direction of time in which disorder or entropy increases. Then, there is the psychological arrow of time. This is the direction in which we feel time passes, the direction in which we remember the past but not the future. Finally, there is the cosmological arrow of time. This is the direction of time in which the universe is expanding rather than contracting.