History
The discovery of vitamin A may have stemmed from research dating back to 1906, indicating that factors other than carbohydrates, proteins, and fats were necessary to keep cattle healthy. By 1917 one of these substances was independently discovered by Elmer McCollum at the University of Wisconsin–Madison, and Lafayette Mendel and Thomas Burr Osborne at Yale University. Since "water-soluble factor B" (vitamin B) had recently been discovered, the researchers chose the name "fat-soluble factor A" (vitamin A). In 1919, Steenbock (University of Wisconsin) proposed a relationship between yellow plant pigments (beta-carotene) and vitamin A. Vitamin A was first synthesized in 1947 by two Dutch chemists, David Adriaan van Dorp and Jozef Ferdinand Arens.
Read more about this topic: Vitamin A
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“The custard is setting; meanwhile
I not only have my own history to worry about
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Unfinished concepts that can never bring themselves to the point
Of being, with or without my help, if any were forthcoming.”
—John Ashbery (b. 1927)
“If you look at the 150 years of modern Chinas history since the Opium Wars, then you cant avoid the conclusion that the last 15 years are the best 15 years in Chinas modern history.”
—J. Stapleton Roy (b. 1935)
“To care for the quarrels of the past, to identify oneself passionately with a cause that became, politically speaking, a losing cause with the birth of the modern world, is to experience a kind of straining against reality, a rebellious nonconformity that, again, is rare in America, where children are instructed in the virtues of the system they live under, as though history had achieved a happy ending in American civics.”
—Mary McCarthy (19121989)