Researchers exposed mice to UV radiation when their XPA was at its minimum level, around 4 a.m., and others to the same rays around 4 p.m., when XPA levels peaked.

研究人员将两组老鼠在不同时段，当XPA达到最低水平，凌晨4点左右，和当XPA达到最高水品，下午4点左右，置于相同的紫外线照射下。

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The real value of the minimum wage peaked in 1968.

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Concentrations of both peaked from Wednesday to Saturday, and fell to a minimum on Monday.

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