题干

卫生部宣告,从2011年5月1日起,我国将在所有室内公共场所、室内工作场所、公共交通工具和其他可能的室外公共场所禁止吸烟.某生物兴趣小组就“吸烟是否有害健康”设计了如下实验:

①取5只1000mL的烧杯,分别贴上标签A、B、C、D、E

②在4份等量的香烟丝中分别加入50mL、40mL、30mL、20mL蒸馏水浸泡一昼夜,滤去残渣得浸出液.

③往B、C、D、E中分别加入上述四组烟草浸出液,A中不加.再分别向A、B、C、D、E中加入清洁池塘水至总量为800mL.

④向A、B、C、D、E中各放入1只蝌蚪,定期喂同种、同量饲料,观察并记录.

根据以上设计,回答下列问题:

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    A new study has discovered that meditation(冥想)and oxygen sport together reduce depression. The Rutgers University study found that this mind and body combination, done twice a week for only two months, reduced the symptoms for a group of students by 40 percent.

    “We are excited by the findings because we saw such a meaningful improvement in both clinically depressed and non-depressed students,” said lead author Dr. Brandon Alderman. “It is the first time that both of these two behavioral ways have been looked at together for dealing with depression.”

    Researchers believe the two activities have an interactive effect on combating depression. Alderman and Dr. Tracey Shors discovered that a combination of mental and physical training (MAP) enabled students with major depressive disorder not to let problems or negative thoughts defeat them.

    Rutgers researchers say those who participated in the study began with 30 minutes of focused attention meditation followed by 30 minutes of oxygen sport. They were told that if their thoughts drifted to the past or the future they should refocus on their breathing, enabling those with depression to accept moment-to-moment changes in attention.

    Shors, who studies the production of new brain cells in the hippocampus—part of the brain involved in memory and learning—says scientists have shown in animal models that oxygen sport exercise keeps a large number of certain cells alive.

    The idea for the human intervention(干预)came from her laboratory studies, she says, with the main goal of helping individuals acquire new skills so that they can learn to recover from stressful life events.

    By learning to focus their attention and exercise, people who are fighting depression can acquire new learning skills that can help them process information and reduce the overwhelming recollection of memories from the past, Shors says.

    “We know these treatments can be practiced over a lifetime and that they will be effective in improving mental health.” said Alderman. “The good news is that this intervention can be practiced by anyone at any time and at no cost.”