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Author Question: The Hadley cell: A) originates with strong solar heating at the equator. B) creates a ... (Read 41 times) |
The Centers for Disease Control and Prevention (CDC) was originally known as the Communicable Disease Center, which was formed to fight malaria. It was originally headquartered in Atlanta, Georgia, since the Southern states faced the worst threat from malaria.
In 1835 it was discovered that a disease of silkworms known as muscardine could be transferred from one silkworm to another, and was caused by a fungus.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
Pope Sylvester II tried to introduce Arabic numbers into Europe between the years 999 and 1003, but their use did not catch on for a few more centuries, and Roman numerals continued to be the primary number system.
Since 1988, the CDC has reported a 99% reduction in bacterial meningitis caused by Haemophilus influenzae, due to the introduction of the vaccine against it.