DNA STRUCTURE DISCOVERED
February 28, 1953 - Cambridge, MA, U.S.A.
James Watson, from early on this Saturday, spent his time at the Cavendish Laboratory in Cambridge, shuffling cardboard cutout models of the molecules of the DNA bases: adenine (A), guanine (G), cytosine (C) and thymine(T). After a while, in a spark of ingenuity, he discovered their complementary pairing. He realized that A joined with T had a close resemblance to C joined with G, and that each pair could hold together with hydrogen bonds. Such pairs could also neatly fit like rungs meeting at right-angles between two anti-parallel helical sugar-phosphate backbones of DNA wound around a common axis. Such structure was consistent with the known X-ray diffraction pattern evidence. Each separated helix with its half of the pairs could form a template for reproducing the molecule. The secret of life!
BALTIMORE & OHIO RAILROAD
February 28, 1827 - Baltimore & Ohio USA
The Baltimore & Ohio Railroad became the first U.S. railway chartered for the commercial transportation of freight and passengers. Investors hoped that a railroad would allow Baltimore, the second largest U.S. city at that time, to successfully compete with New York for western trade. New Yorkers were profiting from easy access to the Midwest via the Erie Canal.
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RANDOM QUOTES
No Man is Above the Law
by Theodore Roosevelt
"..."No man is above the law and no man is below it; nor do we ask any man's permission when we require him to obey it. Obedience to the law is demanded as a right; not asked as a favor."..."
Until a man duplicates a blade of grass
by Earth Day, Thomas Alva Edison Inventor
"...Until a man duplicates a blade of grass, Nature can laugh at his so-called scientific knowledge. Remedies from chemicals will never stand in favorable comparison with the products of Nature, the living cell of a plant, the final result of the rays of the sun, the mother of all life...."
RANDOM FACTS
Cancer Facts & Figures
about Besides Lung Cancer
Besides lung cancer, tobacco use also increases the risk for cancers of the mouth, lips, nasal cavity (nose) and sinuses, larynx (voice box), pharynx (throat), esophagus (swallowing tube), stomach, pancreas, kidney, bladder, uterus, cervix, colon/rectum, ovary (mucinous), and acute myeloid leukemia.
Drug Abuse
about Facts about Drugs
Facts about drugs can protect against drug abuse. Legal drugs, such as alcohol and tobacco, kill more people than illegal drugs. Tobacco (smoking cigarettes) kills more people than any other drug. Illegal drugs including heroin, cannabis, ecstasy and amphetamines can have unknown or dangerous ingredients. Mixing drugs, especially with alcohol, can be fatal.
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Each quarter, twenty general or topical web directories are evaluated and rated according to predetermined criteria. The top ten are placed in competition with one another and ten additional direct...
Drs. Richards and Miller care for a pediatric dental practice dedicated to providing dental care, education and community service to Lake County and surrounding areas.
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