This circulation gets moreor less switched off at night when the temperature gradients disappear or reverse, avoiding heat loss and keeping the nest at a roughly constant temperature.

夜间当温度变化消失或是与白天截然相反时，巢内空气循环减弱，有效避免热流失，使得巢穴室温保持稳定。

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The constant circulation means no refueling interruptions.

这个持续不断的循环意味着没有因补充燃料而中断。

youdao

Thus, there is constant circulation of oil between the pan and the working parts of the engine.

因而在油底壳和发动机工作零件之间有机油不断流动循环。

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But the constant circulation of Somali-Americans back to Somalia to visit family or conduct business makes it hard for American intelligence to track would-be jihadists.

ECONOMIST: Somalia and the United States: What's to be done? | The