Several previous attempts to purify bone marrow for sickle-cell transplants have failed.

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One of the most notable innovations: the development of a new catalyst material to purify exhaust from diesel or other lean-burning engines.

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Sharia is anti-freedom and anti-equality, so to purify oneself in an Islamic sense would necessarily mean something very different from what we in the West would think of as struggling to become a better person.

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To the long list of great ideas gone bad, add the UV Waterworks--a simple, cheap device to purify filthy drinking water in poor countries.

FORBES: Running dry