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Author Question: Covariance is the extent to which a change in one variable corresponds systematically to a change in ... (Read 47 times) |
An identified risk factor for osteoporosis is the intake of excessive amounts of vitamin A. Dietary intake of approximately double the recommended daily amount of vitamin A, by women, has been shown to reduce bone mineral density and increase the chances for hip fractures compared with women who consumed the recommended daily amount (or less) of vitamin A.
It is believed that the Incas used anesthesia. Evidence supports the theory that shamans chewed cocoa leaves and drilled holes into the heads of patients (letting evil spirits escape), spitting into the wounds they made. The mixture of cocaine, saliva, and resin numbed the site enough to allow hours of drilling.
There are more nerve cells in one human brain than there are stars in the Milky Way.
In ancient Rome, many of the richer people in the population had lead-induced gout. The reason for this is unclear. Lead poisoning has also been linked to madness.
The familiar sounds of your heart are made by the heart's valves as they open and close.