And I just want to point out here in terms of things that you're responsible for, you should know that the most probable radius for a 1 s hydrogen atom is equal a nought.

在这里,我想要指出的是，你们要知道氢原子１ｓ轨道,最可能距离等于ａ０

麻省理工公开课 - 化学原理课程节选

And one of the reasons that's most responsible for that is that humans aren't dying at as young an age from infectious diseases as they did three or four hundred years ago.

最重要的一个原因就是,人们不会在年轻的时候死于传染性疾病,而这在三四百年前确实会发生

耶鲁公开课 - 生物医学工程探索课程节选