Generally, a bearish momentum divergence is a red flag warning signal, which often presages a pullback or correction.

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"After the dissuasion by means of whistle-blowing, shouting and hand-flag guiding was of no avail, the Chinese naval vessels fired two red signal shells into the sky as a warning, and the signal shells burned out and extinguished in the air, " Xinhua quoted the official as saying.

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Their idealised version of this question was to ask how two signal chemicals, starting from opposite ends of an embryo, could result in a pattern that looked like the French flag (ie, three different coloured vertical stripes).

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