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The horizontal fraction bar was introduced by the Arabs.

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Barbituric acid, the base material of barbiturates, was first synthesized in 1863 by Adolph von Bayer. His company later went on to synthesize aspirin for the first time, and Bayer aspirin is still a popular brand today.

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Fungal nail infections account for up to 30% of all skin infections. They affect 5% of the general population—mostly people over the age of 70.

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This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.

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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.

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