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Zaki Din

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MATH PUZZLE: Can you replace the question mark with a number?

Edward A. Doisy

Born 13 Nov 1893; died 23 Oct 1986 at age 92.Edward Adelbert Doisy was an American biochemist who shared (with Henrik Dam) the 1943 Nobel Prize for Physiology or Medicine for his isolation and synthesis of vitamin K, a substance that encourages blood clotting (1939), used in medicine and surgery. With the embryologist Edgar Allen (1922-34), he developed assay techniques that facilitated research on sex hormones. Doisy and his associates isolated the sex hormones estrone (theelin, 1929; the first estrogen to be crystallized), estriol (theelol, 1930), and estradiol (dihydrotheelin, 1935). In 1936-39 he isolated two forms of the vitamin, (K1 from lucerne seed and K2 from fish meal, in a pure crystalline form), determined their chemical structures, and synthesized the vitamin.«

Trouble Sleeping

The woman seated herself in the psychiatrists office. "What seems to be the problem?" the doctor asked.
"Well, I, uh," she stammered. "I think I, uh, might be a nymphomaniac."
"I see," he said. "I can help you, but I must advise you that my fee is $80 an hour."
"That's not bad," she replied. "How much for all night?"
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