Yet he would still be practicing medicine today if not for the single-minded persistence of a junior doctor, Andrew Bower, who, unlike virtually everyone else in the university hospital, strongly suspected Colin Bouwer of murder and worked with the police to bring him to justice.

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That is the biggest single reason for the persistence of poverty.

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It isn't clear that any single factor is behind the persistence and growth of pickpocketing and purse snatching in many cities.

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This single piece of legislation, which would have died but for Steiger's persistence, lifted the very weak American capital markets off of their sick beds and spurred an entrepreneurial boom that continues today.

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