The need to feed a growing population is putting much pressure on the world's supply of water. With 97% of the world's water too salty to be drunk or used in agriculture, the worldwide supply of water needs careful management, especially in agriculture. Although the idea of a water shortage(短缺)seems strange to someone fortunate enough to live in a high rainfall country, many of the world's agricultural industries experience constant water shortages.

    Although dams can be built to store water for agricultural use in dry areas and dry seasons, the costs of water redistribution(重新分配)are very high. Not only is there the cost of the engineering itself, but there is also an environmental cost to be considered. Where valleys(山谷)are flooded to create dams, houses are lost and wildlife homes destroyed. Besides, water may flow easily through pipes to fields, but it cannot be transported from one side of the world to the other. Each country must therefore rely on the management of its own water to supply its farming requirements. This is particularly troubling for countries with agricultural industries in areas dependent on irrigation. In Texas, farmers' overuse of irrigation water has resulted in a 25% reduction of the water stores.

    In the Central Valley area of southwestern USA, a huge water engineering project provided water for farming in dry valleys, but much of the water use has been poorly managed.

    Saudi Arabia's attempts to grow wheat in desert areas have seen the pumping of huge quantities of irrigation water from underground reserves. Because there is no rainfall in these areas, such reserves can only decrease, and it is believed that fifty years of pumping will see them run dry.

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    There are a number of special days of the year that are celebrated in different countries. The origins of most of the days are unknown. They were certainly not created by individual people. Other days, however, especially those celebrated in western countries often owe their origins to a particular person. One of the most popular of these, even though it is fairly recent, is Mother's Day. Mothers have always been highly regarded in all cultures. The ancient Romans had a festival known as Hilaria, during which children took presents to the temple of the “Mother of the Gods”. The Christian Church adopted this idea and called it Mothering Sunday. However, over the years this custom was gradually forgotten, and almost disappeared by the end of the 19th century.

    Born in 1864 in Virginia, US, Anna Jarvis was a school teacher and believed children should show gratitude(感激) to their mothers for all their love and care. Encouraged by a friend, she wrote to thousands of important people—politicians, churchmen, doctors, city officials and asked them to support her idea：a special day of the year for thanking mothers.

    In 1910 the Governor of Western Virginia introduced Mother's Day in the state. The date chosen was May 10 — the second Sunday in May, which is still observed in America today. This date was chosen because May 10 was the date on which in 1908 Anna Jarvis's mother died. In 1914 President Woodrow Wilson made May 10 the official date for Mother's Day throughout the United States.

    Soon there was a Mother's Day International Association and the custom began to be adopted in many countries of the world.

    Anna Jarvis, a sad and disillusioned (幻想破灭的) woman died in 1948.The custom she had worked so hard to establish and which had become almost universal had lost its original purpose. It had been taken over by business. As with Christmas, the giving of presents and the sending of cards had become a multi­million dollar industry.

    You may have heard of the American Dream, an ideal that has powered the hopes of Americans for generations.

    It began as a belief that the US was a land of opportunity, and that anyone could achieve success through hard work. The dream has referred to home ownership, a good job, retirement security or each generation doing better than the last for a long time.

    Yet today, this concept seems to have greatly changed. As Tune magazine pointed out, quite different from the older generation, many Millennials (the generation born after 1980) redefine the American Dream as “day-to-day control of your life”. They “prize job mobility, flexible schedules, any work that is more interesting than typing, and the ability to travel”, said the magazine.

    Home ownership, once the cornerstone of the American Dream, is becoming a smaller priority for this generation. Meanwhile, nearly 40% of them choose travel as part of their dream. And running their own business is a rising favorite, as nearly 26% of Millennials consider self-employment as part of their dream.

    So what has led to this huge change?

    Many point fingers at the poor economy. “Modern young Americans seem bound to face a world stamped by ever narrowing opportunity,” noted The Daily Beast.

    “The rate of 16-to-24-year-olds out of school and out of work is unusually high at 15%. Many college graduates have taken jobs that don't require a degree,” Time reported.

    The magazine worries that these difficulties may lead to a lost generation who are “unable to ever truly find their feet on the corporation's ladder”.

    Dan Kadlec, a reporter of Time, sees Millennials as resetting their expectations. “This situation is different for young adults today,” he wrote. “A true American dream has to feel attainable, and many Millennials are feeling they can only attain a day-to-day lifestyle that suits them.”

    This day marks the rising of a new food startup, the first company to be financed entirely by the crowd, and of it every business thus relies on thousands of customers to grow. Lisa, 25, its main founder and CEO, believes it will be a path that will become increasingly popular, and ultimately will produce more thriving（繁荣的）businesses from the scratch.

    “In the food industry, no venture capital (VC, 风险投资) will even look at you until you've hit a million in sales. As a fresh hand in business, unless you're independently wealthy, you will likely need to raise some money before then,” Lisa complained. So few businesses approached VC firms at the beginning. It was no exception with her. Thus, she turned to a new financing tool at hand, crowdfunding, to raise money from the crowd who'd like to take a bet on her company.

    But for a company, it didn't make sense to seek investments when all they had was an idea and a few months of consumer testing data. The food market is extremely competitive. No investor would put money behind a totally unproven new super food product founded by a bunch of twenty-somethings. “But we had a story. And crowds love stories.” Lisa said delightedly. So she put together an online crowdfunding campaign, explaining how she began working with this amazingly nutritious plant in the Peace Corps and then started selling it in the U.S. to support the poor in the West Africa.

    On the online platform where they were to raise the money, a friend convinced them to change their goal from $20,000 to $50,000. Lisa stayed up all night worrying they wouldn't hit it. But they reached $24,000 in 24 hours and ended their funding with $53,000. Seeing the number, Lisa said, “Thank you! To my crowd and for your belief!”

    Smile! It makes everyone in the room feel better because they, consciously or unconsciously, are smiling with you. Growing evidence shows that an instinct for facial mimicry(模仿) allows us to empathize with and even experience other people's feelings. If we can't mirror another person's face, it limits our ability to read and properly react to their expressions. A review of this emotional mirroring appears on February 11 in Trends in Cognitive Sciences.

    In their paper, Paula Niedenthal and Adrienne Wood, social psychologists at the University of Wisconsin, describe how people in social situations copy others' facial expressions to create emotional responses in themselves. For example, if you're with a friend who looks sad, you might "try on" that sad face yourself without realizing you're doing so. In "trying on" your friend's expression, it helps you to recognize what they're feeling by associating it with times in the past when you made that expression. Humans get this emotional meaning from facial expressions in a matter of only a few hundred milliseconds.

    "You reflect on your emotional feelings and then you generate some sort of recognition judgment, and the most important thing that results in is that you take the appropriate action—you approach the person or you avoid the person," Niedenthal says. "Your own emotional reaction to the face changes your perception of how you see the face in such a way that provides you with more information about what it means."

    A person's ability to recognize and "share" others' emotions can be prevented when they can't mimic faces. This is a common complaint for people with motor diseases, like facial paralysis(瘫痪) from a stroke, or even due to nerve damage from plastic surgery. Niedenthal notes that the same would not be true for people who suffer from paralysis from birth, because if you've never had the ability to mimic facial expressions, you will have developed compensatory ways of interpreting emotions.

    People with social disorders associated with mimicry or emotion-recognition damage, like autism(自闭症), can experience similar challenges. "There are some symptoms in autism where lack of facial mimicry may in part be due to limitation of eye contact," Niedenthal says.

    Niedenthal next wants to explore what part in the brain is functioning to help with facial expression recognition. A better understanding of that part, she says, will give us a better idea of how to treat related disorders.

    The world's oceans will likely lose about one-sixth of their fish and other creatures within 100 years if climate change continues on its current path. Every degree Celsius that the world's oceans warm, their biomass is expected to drop five percent, a study found.

    The study predicts that if there is no change in the rate of worldwide greenhouse gas production, there will be a 17-percent loss of biomass by the year 2100. But, if the world reduces carbon pollution, biomass losses could be limited to only about 5 percent.

    Warming temperatures are the biggest issue. But climate change also produces oceans that are more acidic and have less oxygen. This also harms sea life. Much of the world depends on the oceans for food or work.

    The findings make sense and the possible effects of the predicted losses of animal life are huge. "Climate change has the potential to cause serious new conflicts over ocean resource use as the human population continues to grow," said scientists.

    Marine biologist Boris Worm, who helped run the study, added that the "building blocks of marine life—plankton and bacteria—may decline less heavily."

    "Those marine animals that we use directly, and care about most deeply, are predicted to suffer the most," said Worm. He works at Canada's Dalehousie University.

    Scientists had already believed climate change would likely reduce future ocean life. But past computer-based studies looked at only part of the picture or used only one model. The latest study used six different computer models to give the best picture look yet, William Cheung said.

    University of Georgia marine biologist Samantha Joye was not part of the research. But she praised the study as well researched and extremely detailed, and called it "an urgent call for action".