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    While sleeping, some water mammals tend to keep half awake in order to . A. alert themselves to the approaching enemy B. emerge from water now and then to breathe C. be sensitive to the ever?changing environment D. avoid being swept away by rapid currents (C) A nine year old schoolgirl single handedly cooks up a science fair experiment that ends up debunking a widely practiced medical treatment. Emily Rosa's target was a practice known as therapeutic touch , whose advocates manipulate patients' "energy field"to make them feel better and even, say some, to cure them of various ills. Yet Emily's test shows that these energy fields can't be detected, even by trained TT practitioners . Obviously mindful of the publicity value of the situation, Journal editor George Lundberg appeared on TV to declare, "Age doesn't matter. It's good science that matters, and this is good science." Emily's mother Linda Rosa, a registered nurse, has been campaigning against TT for nearly a decade. Linda first thought about TT in the late '80s, when she learned it was on the approved list for continuing nursing education in Colorado. Its 100,000 trained practitioners don't even touch their patients. Instead, they waved their hands a few inches from the patient's body, pushing energy fields around until they’re in "balance." TT advocates say these manipulations can help heal wounds, relieve Pain and reduce fever. The claims are taken seriously enough that TT therapists are frequently hired by leading hospitals, at up to $ 70 an hour, to smooth patients' energy, sometimes during surgery. Yet Rosa could not find any evidence that it works. To provide such proof, TT therapists would have to sit down for independent testing--something they haven't been eager to do, even though James Randi has offered more than $1 million to anyone who can demonstrate the existence of a human energy field. (He's had one taker so far. She failed.) A skeptic might conclude that TT practitioners are afraid to lay their beliefs on the line. But who could turn down an innocent fourth grader? Says Emily: “I think they didn't take me very seriously because I'm a kid." The experiment was straight forward: 21 TT therapists stuck their hands, palms up, through a screen. Emily held her own hand over one of theirs left or right and the practitioners had to say which hand it was. When the results were recorded, they'd done no better than they would have by simply guessing. If there was an energy field, they couldn't feel it. 【查看更多】

     

    题目列表(包括答案和解析)

    　　Birds that are literally half asleep-with one brain hemisphere alert and the other sleeping-control which side of the brain remains awake, according to a new study of sleeping ducks．Earlier studies have documented half brain sleep in a wide range of birds．The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves．The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere's eye stays open and alert．Birds also can sleep with both hemispheres resting at once．

    　　Decades of studies of bird flocks led researchers to predict extra alertness in the more vulnerable, end of the row sleepers．Sure enough, in the end birds tended to watch carefully on the side away from their companions．Ducks in the inner spots showed no preference for gaze direction．

    　　Also, birds dozing(打盹)at the end of the line resorted to single?hemisphere sleep, rather than total relaxation, more often than inner ducks did．Rotating 16 birds through the positions in a four duck row, the researchers found outer birds half asleep during some 32 percent of dozing time versus about 12 percent for birds in internal spots．

    　　“We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness simultaneously in different regions of the brain，”the researchers say．

    　　The results provide the best evidence for a long standing supposition that single hemisphere sleep evolved as creatures scanned for enemies．The preference for opening an eye on the lookout side could be widespread, he predicts．He's seen it in a pair of birds dozing side by side in the zoo and in a single pet bird sleeping by a mirror．The mirror side eye closed as if the reflection were companion and the other eye stayed open．

    　　Useful as half sleeping might be, it's only been found in birds and such water mammals(哺乳动物)as dolphins, whales, and seals．Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning．

    　　Studies of birds may offer unique insights into sleep．Jerome M．Siegel of the UCLA says he wonders if birds' half brain sleep“is just the tip of the iceberg(冰山)”He speculates that more examples may turn up when we take a closer look at other species．

    (1)

    A new study on birds' sleep has revealed that ________．

    [　　]

    A．

    half brain sleep is found in a wide variety of birds

    B．

    half brain sleep is characterized by slow brain waves

    C．

    birds can control their half brain sleep consciously

    D．

    birds seldom sleep with the whole of their brain at rest

    (2)

    According to the passage, birds often half sleep because ________．

    [　　]

    A．

    they have to watch out for possible attacks

    B．

    their brain hemispheres take turns to rest

    C．

    the two halves of their brain are differently structured

    D．

    they have to constantly keep an eye on their companions

    (3)

    The example of a bird sleeping in front of a mirror indicates that ________．

    [　　]

    A．

    the phenomenon of birds dozing in pairs is widespread

    B．

    birds prefer to sleep in pairs for the sake of security

    C．

    even an imagined companion gives the bird a sense of security

    D．

    a single pet bird enjoys seeing its own reflection in the mirror

    (4)

    While sleeping, some water mammals tend to keep half awake in order to ________．

    [　　]

    A．

    alert themselves to the approaching enemy

    B．

    emerge from water now and then to breathe

    C．

    be sensitive to the ever changing environment

    D．

    avoid being swept away by rapid currents

    查看答案和解析>>

    　　Birds that are literally half asleep－with one brain hemisphere alert and the other sleeping－control which side of the brain remains awake, according to a new study of sleeping ducks．Earlier studies have documented half brain sleep in a wide range of birds．The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves．The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere's eye stays open and alert．Birds also can sleep with both hemispheres resting at once．

    　　Decades of studies of bird flocks led researchers to predict extra alertness in the more vulnerable, end of the row sleepers．Sure enough, in the end birds tended to watch carefully on the side away from their companions．Ducks in the inner spots showed no preference for gaze direction．

    　　Also, birds dozing(打盹)at the end of the line resorted to single hemisphere sleep, rather than total relaxation, more often than inner ducks did．Rotating 16 birds through the positions in a four duck row, the researchers found outer birds half asleep during some 32 percent of dozing time versus about 12 percent for birds in internal spots．

    　　"We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness simultaneously in different regions of the brain，"the researchers say．

    　　The results provide the best evidence for a long standing supposition that single hemisphere sleep evolved as creatures scanned for enemies．The preference for opening an eye on the lookout side could be widespread, he predicts．He's seen it in a pair of birds dozing side by side in the zoo and in a single pet bird sleeping by a mirror．The mirror side eye closed as if the reflection were companion and the other eye stayed open．

    　　Useful as half sleeping might be, it's only been found in birds and such water mammals(哺乳动物)as dolphins, whales, and seals．Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning．

    　　Studies of birds may offer unique insights into sleep．Jerome M．Siegel of the UCLA says he wonders if birds' half brain sleep "is just the tip of the iceberg(冰山)" He speculates that more examples may turn up when we take a closer look at other species．

    (1)

    A new study on birds' sleep has revealed that ________．

    [　　]

    A．

    half brain sleep is found in a wide variety of birds

    B．

    half brain sleep is characterized by slow brain waves

    C．

    birds can control their half brain sleep consciously

    D．

    birds seldom sleep with the whole of their brain at rest

    (2)

    According to the passage, birds often half sleep because ________．

    [　　]

    A．

    they have to watch out for possible attacks

    B．

    their brain hemispheres take turns to rest

    C．

    the two halves of their brain are differently structured

    D．

    they have to constantly keep an eye on their companions

    (3)

    The example of a bird sleeping in front of a mirror indicates that ________．

    [　　]

    A．

    the phenomenon of birds dozing in pairs is widespread

    B．

    birds prefer to sleep in pairs for the sake of security

    C．

    even an imagined companion gives the bird a sense of security

    D．

    a single pet bird enjoys seeing its own reflection in the mirror

    (4)

    While sleeping, some water mammals tend to keep half awake in order to ________．

    [　　]

    A．

    alert themselves to the approaching enemy

    B．

    emerge from water now and then to breathe

    C．

    be sensitive to the ever changing environment

    D．

    avoid being swept away by rapid currents

    查看答案和解析>>


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