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.

    Housework is a frequent source of disputes (争论) between lazy husbands and their hard-working wives, but women have been warned not to expect men to pull their weight any time soon.

    A study from Oxford University has found that men are unlikely to be doing an equal share of housework before 2050. Mothers, the researchers warned, will continue to shoulder the burden of childcare and housework for the next four decades, largely because housework such as cleaning and cooking is still regarded as“women's work”.

    The gap between the amount of time men and women spend on housework has narrowed slowly over the past 40 years. But it will take another four decades before true housework equality is achieved, the study concluded. The research found that in the Nordic countries, the burden of housework is shared more equally between men and women. In the UK, women spend an average of four hours and forty minutes each day on housework, compared with two hours and twenty-eight minutes for men. This is an improvement from the 1960s, when British women typically spent six hours a day on housework, while men spent just 90 minutes every day.

    But progress towards housework equality appears to be slowing in some countries. Dr Oriel Sullivan, a research reader from Oxford's Department of Sociology, said, “we've looked at what is affecting the equality in the home, and we have found that certain tasks seem to be given according to whether they are viewed as ‘men's work' or ‘women's work'.”Dr Sullivan said cultural attitudes taught at school may be responsible for the views of housework. “At school it is much easier for a girl to be a tomboy, but it is much more difficult for a boy to enjoy baking and dancing,” she said.

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    They may be teenagers, but 17-year-old Brittany Bull and 16-year-old Sesam Mngqengqiswa have grand ambitions(雄心) — to launch Africa's first private satellite (卫星) into space. They are part of a team of high school girls from Cape Town, South Africa, who have designed and built equipment for a satellite that will orbit over the earth's poles scanning Africa's surface.

    Once in space, the satellite will collect information on agriculture, and food security within the continent. Using the data/we can try to determine and predict (预测) the problems Africa will be facing in the future”, explains Bull, a student at Pelican Park High School.“Where our food is growing, where we can plant more trees and vegetation and also how we can monitor remote areas,” she says. “We have a lot of forest fires and floods but we don't always get out there in time.'' Information received twice a day will go towards disaster prevention.

    It's part of a project by South Africa's Meta Economic Development Organization (MEDO) working with Morehead State University in the US.

The girls (14 in total) are being trained by satellite engineers from Cape Peninsula University of Technology, in an effort to encourage more African women into STEM (science, technology, engineering, mathematics).

    Scheduled to launch in May 2017, if successful, it will make MEDO the first private company in Africa to build a satellite and send it into orbit.

    Mngqengqiswa comes from a single parent household. Her mother is a domestic worker. By becoming a space engineer or astronaut, the teenager hopes to make her mother proud. “Discovering space and seeing the Earth's atmosphere, it's not something many black Africans have been able to do, or get the opportunity to look at I want to see and experience these things for myself,” says Mngqengqiswa.

    Her team mate Bull agrees, “I want to show to fellow girls that we don't need to sit around or limit ourselves. Any career is possible-even aerospace.”

    Once there was an 11-year-old boy who went fishing with his father in the middle of the Finger lake. On the day before salmon(鲑鱼) season opened, they were fishing early in the evening, catching other fish with worms. Then the boy tied on a small silver lure (鱼饵) and put it into the lake. Suddenly he felt that something very big pulling on the lure. His father watched with admiration as the boy skillfully brought the fish beside the bank. Finally he lifted the tired fish from the water. It was the largest one he had ever seen, but it was a salmon.

    The boy and his father looked at the big fish. The father lit a match and looked at his watch. It was 10 pm – two hours before the season opened. He looked at the fish, then at the boy. “You'll have to put it back, son,” he said.

    “Dad!” cried the boy, “There will be other fish,” said his father. “Not as big as this one,” cried the boy. He looked around the lake. No other fishermen or boats were in sight in the moonlight. He looked again at his father.

    Even though no one had seen them, nor could anyone ever know what time he had caught the fish, the boy could tell from his father's voice that the decision couldn't be changed. He threw the huge salmon into the dark water. The big fish disappeared. The boy thought that he would never again see such a big fish.

    That was 34 years ago. Today the boy is an successful architect in New York City. He often takes his own son and daughters to fish at the same place.

    And he was right. He has never again caught such a large fish as the one he got that night long ago. But he does see that same fish … again and again … every time he has an ethical (伦理的，道德的) decision to make. For, as his father had taught him, ethics are simple matters of right and wrong. It is only the practice of ethics that is difficult.