Collectively, these cycles are known as circadian rhythms and are generally tied to the 24-hour day-night cycle.
所有的这些周期被人们统称为昼夜节律，一般以24小时一昼夜为一个循环。
2
Jet lag happens when your circadian rhythm is running on a different day-night cycle than the day-night cycle of the outside world.
当我们的生物钟周期与外部的昼夜交替周期不一致时，我们就有倒时差的感觉。
3
WJFACs are designed to be effective even in shallow waters, and have day-night surveillance capability and firepower that will enhance coastal security, an Indian Navy official said.