Sleep deprivation(缺失)is an important hidden factor in lowering the achievement of school pupils, according to researchers carrying out international education tests.

    It is a particular problem in richer countries with sleep experts linking it to the use of mobile phones and computers in bedroom late at night. Sleep deprivation is such a serious problem that lessons have to be dragged down to a lower level to suit sleep-deprived learners, the study found. The international comparison, carried out by Boston College, found the United States to have the highest number of sleep-deprived students, with 73% of 9- and 10-year-olds and 80% of 13- and 14-year-olds identified by their teachers as being negatively affected.

    In literacy(读写能力) tests there were 76% of 9- and 10-year-olds lacking sleep. This was much higher than the international average of 47% of primary pupils needing more sleep and 57% among the secondary age group.

    Other countries with the most sleep-deprived youngsters were New Zealand, Saudi Arabia, Australia, England, Ireland and France. High-performing Finland is also among the most lacking in sleep. Countries with the best records for getting enough sleep include Azerbaijan, Kazakhstan, Portugal, the Czech Republic, Japan and Malta.

    The analysis was part of the huge date-gathering process for global education rankings, the Trends in International Mathematics and Science Study(TIMSS)and Progress in International Reading Literacy Study(PIRLS)

    “I think we underestimate the impact of sleep. Our data show that across countries internationally, on average, children who have more sleep achieve higher in maths, science and reading. That is exactly what our data show,” says Chad Minnich of the TIMSS and PIRLS International Study Center.

    “It's the same link for children who are lacking basic nutrition,” says Mr Minnich, based at the Lynch School of Education, Boston College. “If you are unable to concentrate, to attend mentally, you are unable to achieve at your best level, because your mind and body are in need of something more basic. Sleep is a fundamental need for all children. If teachers report such large proportions of children suffering from lack of sleep, it's having a significant impact. But worse than that, teachers are having to adjust their instruction based on those children who are suffering from a lack of sleep. The children who are suffering from a lack of sleep are driving down instruction.”

    That means that even the children who are getting enough sleep are still suffering from this sleep-related lowering.

    I used to believe courtesy(礼貌) was a thing of the past. Very seldom have I encountered a courteous human being in this modem era of the so called Generation X.

    Recently, I had to change my thinking, when I came face to face with just such a human being. I had gone to a happening coffee place, with two of my grown up daughters. The place was crowded with the usual loud crowd and we had to climb a sleep flight of stairs in order to find an empty table. After enjoying coffee and snacks, we were at the steep descent down the stairs, where the narrow space made climbing down only possible in a single file, with hardly any space for another person to either climb up or come down.

    Just as I was in the middle of my descent, a gentleman entered the main entrance of the restaurant which right in front of the staircase. I was sure I would be pushed roughly by this man who will want to go up in a hurry. I kept coming down as fast as I could, holding on to the banister (栏杆), instead of my advanced years. My agile daughters were already down, looking up at me worriedly, hoping I would reach them before the stranger strange started up the stairs, knowing I was a nervous sort.

    Nearly reaching them, I noticed the man still standing near the door. I reached my daughters and passed the stranger at the entrance door which he kept holding open. I looked back thinking he was still at the door, deciding whether to go in or find another less crowded place. I saw him going up the stairs, two at a time. I told my daughters about it and all three of us felt had that we did not even thank the courteous gentleman who was actually holding the door open for us ladies to pass through before going up.

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    Anger often makes us uncomfortable. When you find your anger too uncomfortable to process, please let it go. But remember to create a healthy anger in your children is to practice creating a healthy anger in yourself. Once you're better at experiencing anger and expressing it in a healthy way, you'll be able to model a good style of anger for your kids.

    Some kids deal with anger by creating a "false self": a child who is perfect for their parents. People who have developed a false self are often passive aggressive and seem shallow because they've hid away all the feelings with depth and character.

    How do we keep kids from creating false selves? We need to raise them in an environment where it's safe to express feelings. Once you feel more comfortable with your own anger, you can teach your children why anger is a helpful emotion. When your kid expresses anger, help them examine what it is that has made them angry. Why did it make them angry? How did it do that? Then, you can teach them that while emotions are never wrong and are always valid, our expressions of our emotions are within our control.

    People who are afraid of their own anger will never learn how to listen to what their anger is trying to tell them. Instead of teaching our kids that their anger is wrong, that "happy families" are never angry, or that all feelings of anger lead to violence and fear, we can teach our children that anger is OK. Anger is natural, it is normal, and it can be experienced and expressed in a healthy way.

    Driving in Canada is similar to driving in many parts of the United States. Distances and speeds, however, are posted in kilometers per hour and some signs, particularly in Quebec, may only be in French.

    Unless otherwise posted, the maximum (最大限度的) speed limit in Canada is 50km/hr in cities and 80km/hr on highways. On rural highways, the posted speed limit may be 100km/hr. It is illegal to take automobile radar detectors (汽车雷达检测器) into Quebec, Ontario, Manitoba, and the Yukon. Seat belt use is required by law for all passengers, and child car seats must be used by children under 40 pounds. Some provinces require drivers to keep their vehicles' headlights on during the day and some have banned (禁止) driving while using a hand-held cell phone. Motorcycles cannot share a lane (车道), and safety helmets for motorcycle riders and passengers are necessary. Running a red light is a serious crime throughout Canada and drivers are advised to stop before starting when a light turns green.

    Winter travel can be dangerous due to heavy snowfalls and icy conditions. Some roads and bridges are often closed in winter. Snow tires are required in some provinces. Travelers should also be careful about animals while driving at night in rural areas.

    Highway 401, from Detroit to Montreal, is one of the busiest highways in North America. It has been the scene of many deadly traffic accidents due to sudden and severe weather changes, high rates of speed, and heavy truck traffic. Thus drivers should be alert while travelling here.

    Please refer to our Road Safety page for more information. Also, we suggest that you visit the website of Canada's national authority responsible for road safety.

    Andy rode slowly on his way to school, day-dreaming about the fishing trip that his father had promised him. He was so busy dreaming about all the fish he would catch that he was unaware of everything else around him.

    He rode along until a strange sound drew him to the present. He came to a stop and looked up to the sky. What he saw frightened him. A huge group of bees filled the sky like dark cloud and seemed to be heading angrily towards him.

    With no time to waste Andy sped off in the opposite direction, riding quickly without knowing how to escape the group. With a rapidly beating heart and his legs pumping quickly, he sped down the rough road. As the bees came closer, his fear increased. Andy knew that he was sensitive(敏感的) to bee stings (蜇). Last time a sting had put him in hospital—and that was only one bee sting! He had been forced to stay in bed for two whole days. Suddenly, his father's words came to him. "When you are in a dangerous situation, don't panic. Stay calm, use your brain and think your ways out of it."

    On a nearby hill, he could see smoke waving slowly from the chimney(烟囱) of the Nelson family home. "Bees don't like smoke," he thought. "They couldn't get into the house." Andy raced towards the Nelson house, but the bees were gaining around. Andy knew he could not reach the house in time. He guessed that the bees would catch up with him soon.

    Suddenly, out of the corner of his eyes, he saw a small pond used by Mr. Nelson to water his vegetable garden. Off his bike and into the cool water he jumped, disappearing below the surface and away from the bees. After holding his breath for as long as he could, Andy came up for air and noticed the bees have gone. Pulling himself out of the water, he walked up the hill and rang the doorbell. Mr. Nelson took him inside and rang his mother.

    "You'll really need that fishing break to help you recover(恢复)," laughed his mother. "Thank goodness you didn't panic!" But Andy did not hear her. He was dreaming once again of the fish he would catch tomorrow.

    The meaning of silence varies among cultural groups. Silences may be thoughtful, or they may be empty when a person has nothing to say. A silence in a conversation may also show stubbornness, uneasiness, or worry. Silence may be viewed by some cultural groups as extremely uncomfortable; thus efforts may be made to fill every gap(间隙) with conversation. Persons in other cultural groups value silence and view it as necessary for understanding a person's needs.

    Many Native Americans value silence and feel it is a basic part of communicating among people, just as some traditional Chinese and Thai persons do. Therefore, when a person from one of these cultures is speaking and suddenly stops, what may be implied(暗示) is that the person wants the listener to think about what has been said before continuing. In these cultures, silence is a call for thinking.

    Other cultures may use silence in other ways, particularly when dealing with disagreements among people or in relationships of people with different amounts of power. For example, Russian, French, and Spanish persons may use silence to show agreement between parties about the topic under discussion. However, Mexicans may use silence when instructions (指示，命令) are given by a person in authority rather than be rude to that person by arguing with him or her. In still another use, persons in Asian cultures may view silence as a sign of respect, particularly to an elder or a person in authority.

    Nurses and other care-givers need to notice the possible meanings of silence when they come across the personal worries their patients may be experiencing. Nurses should recognize their own personal and cultural construction of silence so that a patient's silence is not disturbed too early or allowed to go on unnecessarily. A nurse who understands the healing(治愈) value of silence can use this understanding to help in the care of patients from their own and from other cultures.