The horizontal fraction bar was introduced by the Arabs.
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In 1844, Charles Goodyear obtained the first patent for a rubber condom.
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The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
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The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
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Drugs are in development that may cure asthma and hay fever once and for all. They target leukotrienes, which are known to cause tightening of the air passages in the lungs and increase mucus productions in nasal passages.