题干

如图为胸腔和肺的示意图,当肋间外肌和膈肌收缩时,图中三部位压力由大到小的顺序是(  )

A:c>a>b 

B:a>b>c 

C:a>c>b

D:b>c>a

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B

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    The bed should be reserved as a place for sleep, but people tend to read an iPad a lot in bed before they go to sleep.

    Charles Czeisler, a professor at Harvard Medical School, and his colleagues got a small group of people for an experiment. For five days in a row, the people read either a paper book or an iPad for four hours before sleep. Their sleep patterns were monitored all night. Before and after each trial period, the people took hourly blood tests to paint a day-long picture of just how much melatonin (褪黑激素) was in their blood at any given time.

    When subjects read on the iPad as compared to the paper books, they reported feeling less sleepy at night and less active the following morning. People also took longer to fall asleep on the iPad nights, and the blood tests showed that their melatonin secretion (分泌) was delayed by an hour and a half.

    The researchers conclude in today's journal article that given the rise of e-readers and the increasingly widespread use of e-things among children and adolescents, more research into the long-term consequences of these devices on health and safety is urgently needed. Czeisler and colleagues go on, in the research paper, to note:“Reading an iPad in bed may increase cancer risk.”

    However, software has been developed that can reduce some of the blue light from the screens of phones and computers according to time of day, and there are also glasses that are made to filter (过滤) short wavelengths. While they seem like a logical solution for the nighttime tech users, it needs more research.

同类题5

完形填空

    Seven years ago, I began accompanying my father to the local market to sell vegetables we harvested from our farm. At the beginning , I did what I could to1him while I also communicated with other participants in the market.

    As time went by, I increasingly2the craft of gardening,3I began planting a garden of my own to4a seller myself. The market soon became my5for many summers to come. The sellers in the market were6and more than willing to share their gardening experience. Many sellers were the new generation of farmers and acquired knowledge through the experience of their7. The years I participated in the market helped me grow, taught me many new skills and opened doors to success I8imagined.

    Responsibility came rather quickly as I 9to manage my own gardening business. There was a huge of work being self10. I had to do everything by myself. I learned that self-discipline(自我约束) and time management were important in order to11a productive garden. Rising 12in the morning at 4 a. m. to arrive at the market with my13produce ensured I would be there to greet early 14 .

    The market opened a door of opportunity I never dreamed of. It15me to make a profit to start a greenhouse business. It is a(n)16feeling when I see the seeds come out and raise them as they continue to17until they are ready for sale. I've learned18because it is impossible to rush Mother Nature! It takes time and work to make the plants grow and become mature. It is not an overnight19. Several weeks are required for the plants to be ready, but the 20is worth all the time I spend and all work I do.