题目内容
回答题。
Dreams
Of all the components of a good night&39;s sleep, dreams seem to be least within our control. In dreams, a window opens into a world where logic is suspended and dead people speak. A century ago, Freud formulated this revolutionary theory that dreams were the disguised shadows of our unconscious desires and fears; by the
late 1970s, neurologists had switched to thinking of them as just "mental noise" -- the random byproducts of the neural-repair work that goes on during sleep. Now researchers suspect that dreams are part of the mind&39;s emotional thermostat, regulating moods while the brain is "off-line" . And one leading authority says that these intensely powerful mental events can be not only harnessed but actually brought under conscious control, to help us sleep and feel better. "It&39;s your dream, " says Rosalind Cartwright, chair of psychology at Chicago&39;s Medical Center, "If you don&39;t like it, change it. "
Evidence from brain imaging supports this view. The brain is as active during REM (rapid eye movement ) sleep --when most vivid dreams occur -- as it is when fully awake, says Dr. Eric Nofzinger at the University of Pittsburgh. But not all parts of the brain are equally involved; the limbic system (the "emotional brain" ) is especially active, while the prefrontal cortex (the center of intellect and reasoning ) is relatively quiet. "We wake up from dreams happy or depressed, and those feelings can stay with us all day, " says Stanford sleep researcher Dr. William Dement.
The link between dreams and emotions shows up among the patients in Cartwright&39;s clinic. Most people seem to have more bad dreams early in the night, progressing toward happier ones before awakening, suggesting that they are working through negative feelings generated during the day. Because our conscious mind is occupied with daily life we don&39;t always think about the emotional significance of the day&39;s events -until, it appears, we begin to dream.
And this process need not be left to the unconscious. Cartwright believes one can exercise conscious control over recurring bad dreams. As soon as you awaken, identify what is upsetting about the dream. Visualize how you would like it to end instead; the next time it occurs, try to wake up just enough to control its course. With much practice people can learn to, literally, do it in their sleep.
At the end of the day, there&39;s probably little reason to pay attention to our dreams at all unless they keep us from sleeping or "we wake up in panic, " Cartwright says. Terrorism, economic uncertainties and general feelings of insecurity have increased people&39;s anxiety. Those suffering from persistent nightmares should seek
help from a therapist. For the rest of us, the brain has its ways of working through bad feelings. Sleep—or rather dream -- on it and you&39;ll feel better in the morning.
Researchers have come to believe that dreams__________ 查看材料
查看答案
搜索结果不匹配？点我反馈
更多问题
Paragraph 4__________ 查看材料
Paragraph 3__________ 查看材料
The first A3 ×× will be available in 2003. 查看材料
回答题。
Keeping Cut Flowers
1. While everybody enjoys fresh cut flowers around his house, few people know how to keep them for as long as possible. This may be done by keeping in mind a few simple facts.
2. An important thing to remember about cut flowers is that they are sensitive to temperature. For example, studies have shown that cut carnations (康乃馨 ) retain their freshness eight times longer when kept at 12℃ than when kept at 26℃. Keeping freshly harvested flowers at the fight temperatures is probably the most important aspect of flower care.
3. Flowers are not intended by nature to live very long. Their biological purpose is simply to attract birds or insects, such as bees, for pollination (授粉 ) . After that, they quickly dry up and die. The process by which flowers
consume oxygen and produce carbon dioxide (二氧化碳 ) , called respiration (呼吸 ) , generates the energy the flower needs to give the flower its shape and colour. The making of seeds also depends on this energy. While all living things respire, flowers have a high level of respiration. A result of all this respiration is heat, and for flowers the level of heat relative to the mass of the flower is very high. Respiration also brings about the eventual death of the flower. Thus the greater the level of respiration, the sooner the flower dies.
4. How, then, to control the rate at which flowers die？ By controlling respiration. How is respiration controlled？ By controlling temperature. We know that respiration produces heat, but the reverse is also true. Thus by maintaining low temperatures, respiration is reduced and the cut flower will age more slowly.
5. Another vital factor in keeping cut flowers is the quality of the water in which they are placed. Flowers find it difficult to "drink" water that is dirty or otherwise polluted. Even when water looks and smells clean, it almost certainly contains harmful substances that can endanger the flowers. To rid the water of these unwanted substances, household chlorine bleach (含氯漂白剂 ) can be used in small quantities. It is recommended that 15 drops of chlorine bleach (at 4% solution ) be added to each litre of water. The water and solution should also be replaced each day.
Paragraph 2__________ 查看材料
微信支付 
支付宝支付