That's less than the participants' daily variation, and likely within the level of error for the instrument used to detect it.

那比参与者日常变化量还低，并且在检测工具允许的误差范围内。

We're interested in diurnal, that is daily, variation.

我们感兴趣的是昼夜变化，也就是每天的变化。

We're interested in diurnal, I mean daily, variation.

我们对昼夜变化感兴趣，我的意思是每天变化。

Our interest is not so much in that diurnal or daily variation.

我们的兴趣并不在于那种昼夜变化或日常变化。

Their interest is not so much in diurnal or daily variation.

他们的兴趣不在于昼夜或日常变化。