Science of the Occult

Halloween conjures visions of ghosts, hauntings and many unexplained phenomena that play on our worst fears

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HealthOctober 21, 1999

How do scientists make artificial blood? How effective is it compared with the real thing?

The SciencesOctober 21, 1999

How does the fluoride in toothpaste prevent cavities? Is there any kind of 'natural' fluoride protection, or is it only in artificial compounds?