Npswarn is the threshold that is used to signal the processes when space is getting low.

Npswarn是当空间变得较低时用于通知进程的阈值。

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Infrared radiation heats up the pit membrane tissue, and TRPA1 channels open when a threshold temperature is reached, allowing ions to flow into the nerve cells and triggering an electrical signal.

红外线使窝器膜组织升温，当达到阈值后TRPA 1通路打开，离子流入神经细胞并催发电信号。

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In this sense threshold means a sort of transition point like the threshold when an FM radio signal breaks through from being just static to being music (or maybe an AD).

从这个意义上讲，“threshold”意味着一种临界点，就像一个开关，使得FM无线电信号从静止状态到播放音乐状态(或者，也可能是一个广告)的忽然变化。

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But now this mysterious property is up for sale, and so I find myself with a few other journalists on the other side of the doors, signing consent forms and handing in my mobile phone (whose signal had mysteriously vanished as soon as I crossed the threshold).

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It is also not just the fact that it sends a signal of American weakness to Iran and its proxies just as Iran reaches the nuclear threshold.

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