The dip, he says, was triggered by a burst of volcanic activity that deposited new silicate rocks.

他表示，低浓度是由一系列火山活动储存新的硅酸盐岩石触发的。

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Economic activity now appears to have declined by 4.1% from peak to trough, easily outstripping the 3.7% dip observed in the downturn of 1957-58 (in 1981-82 the drop was just under 3%).

现阶段，经济活动的峰谷差为4.1%，大大会超过了1957 - 58年经济衰退时3.7%的最低点。(1981 - 82年，下降不到3%)。

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By using a laser to induce pain, Brown and his team found that activity in certain parts of the brain seemed to dip when the study participants anticipated pain.

在使用激光诱发疼痛时，布朗教授和他的研究小组发现，当被研究者预期疼痛时，大脑某部位的活力看起来在下降。

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