warning signal

基本解释

E. coli bacteria were modified using BioBrick components to produce a warning signal in the presence of arsenic.
他们利用生物砖组件改变大肠杆菌使其在遇到砷的时候发出警告信号。
This adds yet another layer of complexity to control efforts and removes the warning signal for humans to avoid risky behaviours.
这就使控制疫情的努力更趋复杂，使人类难以察觉避免危险行为的警示信号。
Klopper said he was unaware of details, but past speculation has included sonar buoys able to identify sharks and transmit a warning signal.
发言人克劳普说他不知道具体细节，但是之前传闻内容涉及声纳浮标，它能够识别鲨鱼并传出警告信号。

But that whistling past the graveyard ignores the bright flashing warning signal that Romney has reaffirmed.
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Generally, a bearish momentum divergence is a red flag warning signal, which often presages a pullback or correction.
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Until the last two years, that was always a very important warning signal.
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