McEwen said his research has found even more signs that repeated stress actually causes neurons in the brain to shrink, at least in rats.

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William Rankine, a Scottish engineer and one of the fathers of thermodynamics, was the first to explain how these repeated stress reversals could cause cracks to propagate.

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The important thing here is the repeated stress on "development".

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Ilan Meyer, a senior scholar at UCLA's School of Law, offers an explanation for these disparities through the "Theory of Minority Stress, " which suggests that these health inequities may be rooted in discrimination, with negative health behaviors acting as coping mechanisms for repeated exposure to stigma-related stress.

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There have been repeated warnings from teachers' unions about the stress caused by increased workloads, a culture of testing and inspections, and unruly behaviour by pupils.

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