Pheromones: they're those chemical signals often associated with attraction. But there are many chemical signals we give off-including ones that might signal alarm, aggression or other emotions.

信息素是一种化学信号，常与吸引力有关。我们散发出的化学信号有许多种，包括那些传递警觉，攻击或者其他情绪的化学信号。

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If they detect something wrong while the system is armed, they'll transmit a wireless alert signal to a base station that will then raise the alarm.

如果他们在系统布防时发现了什么问题，就会向基站发送无线警报信号，然后基站会发出警报。

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This alarm sends a signal to your adrenal glands to release a surge of stress hormones, including adrenaline and cortisol.

这个警报传递出一个信号给肾上腺使其释放出大量的应激激素，包括肾上腺素和皮质醇。

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In addition, he said, bees had at their disposal a much more powerful chemical alarm signal.

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The fall in investment, particularly capital spending, reported in the GDP announcement is an alarm signal, says Mario Ohoven, president of the Association for Small and Medium-Size Businesses.

ECONOMIST: German economy: Europe��s tired engine | The

Sure enough, four days in, our routine 530am radio signal snare check generated hysteria to rival any alarm clock.

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