The absolute number that you assign to it is something that's arbitrary. You have to set what the zero is. And so there's a well-understood convention for what the zero is.

你指定给它的绝对值是有任意性的,你需要设定零点的位置,因此有一个经过充分研究的,关于设定零点的约定。

麻省理工公开课 - 热力学与动力学课程节选

Through many decades of study, biologists have teased out certain populations of cells within the bone marrow that are capable of reproducing subsets of cells.

经过数十年的研究,生物学家们在骨髓中发现了,一些细胞群,它们能够生成细胞亚群

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So this diet, although it's processed by a company and sold for people doing animal studies, it more or less mimics what these animals might be eating under natural conditions.

尽管这些食物经过商业加工,并用于动物科学研究,但会尽可能的模拟,实验动物在自然环境下的饮食

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