PTSD, an anxiety disorder, can develop after a terrifying or life-threatening event, or a series of events causing extreme stress.

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The person who initially found the envelope is being treated at a Phoenix-area hospital for a pre-existing condition and stress from the event, and others in the immediate vicinity were examined as well.

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He reasoned that excessive amounts of stress hormones released at the time of a traumatic event might be responsible for overly strong memory formation.

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In any event, they stress, Arrow is seen not as a panacea, but as part of a wide array of strategies, including deterrence, civil and counter-strikes.

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Lord Coe used the event to stress that the Games would be used to encourage a future generation to take part in sport.

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