Sunday, December 8, 2013
In addition to his practice Ingenhousz studied physics in his own laboratory, with his first successful publication at age 28. Because he was a Catholic there was no possibility of him getting a university position in the Netherlands and he remained there until his father died in 1764. Intending to travel Europe and study he started in England where he learned about smallpox vaccination. He became a master inocculator and successfully combated an epidemic in Hertfordshire. Upon the recommendation of John Pringle, a family friend, Ingenhousz traveled to Vienna where he inoculated the Empress Mary Theresa and her family. As a reward for his services Ingenhousz was appointed court physician.
In 1779 Ingenhousz returned to England and began research on photosynthesis. Photosynthesis is the process by which plants take up carbon dioxide out of the air and use it to make sugar. The process requires sunlight and produces oxygen gas. Ingenhousz experimented by placing plants under water and exposing them to sunlight. He noticed that they produce gas bubbles on the underside of their leaves. He collected this gas and identified it as oxygen, which Joseph Priestly had described only a few years earlier. In addition to the discovery of photosynthesis Ingenhousz is also the discovery of brownian motion from his observation to coal dust on the surface of alcohol. For his discoveries Ingenhousz was made a member of the Royal Society that same year, 1779.
Ingenhousz died on September 7, 1799 in Claine, England, where he is buried.
Harvey, R.B. and Harvey, Helen M. Whittier; "Brief Paper on Jan Ingenhousz"; Plant Physiology (1930)5:282-287
McCarthy, Eugene M.; "Jan Ingenhousz"; Macroevolution.net
Jan Ingenhousz Wikipedia Entry
Sunday, December 1, 2013
Rodbell did his postdoctoral work at the University of Illinois at Urbana-Champaign where he worked for two years as a research assistant. In 1956 he took a position as a research biochemist in the laboratory of in the laboratory of Christian Anfinsen at the National Heart Institute where he studied the composition of lipid proteins and the role of glucose in adipose tissue. In 1961 Rodbell transferred to the National Institute of Arthritis and Metabolic Disease (now part of the National Institute of Diabetes and Digestive and Kidney Diseases). The move also coincided with a change in the focus of his research moved away from studying phospholipids and began researching cellular second messenger systems.
Second messengers are chemicals that are let into or produced inside a cell in response to an outside signal. The production or ingress of second messengers is stimulated by the reception of a chemical signal at a receptor protein embedded in the cellular membrane. Rodbell was researching the effects of glucagon on rat liver cells and discovered g-proteins, a series of inter-cellular proteins that are linked to cellular membrane embedded receptors which can activate transcription and protein production. These proteins are used throughout the endocrine system as a means of coupling the extra-cellular signal with internal cell activity. For his discoveries the g-proteins Rodbell shared the 1994 Nobel Prize in Physiology or Medicine with Alfred G. G. Gilman.
Rodbell retired in 1994 and died on December 7, 1998 of multiple organ failure.
Rodbell, Martin; Nobel Autobiography at nobelprize.org
Biographical Matter at The Martin Rodbell papers at nlm.nih.gov
Martin Rodbell Wikipedia Entry
Sunday, November 17, 2013
Taking compass readings in Deptford, Gellibrand compared his readings to those taken 12 years early he determined that declination (the angle between true, geographic north and magnetic north) had changed. Declination varies at different places, but Gellibrand was the first to observe its variation with time. He published his results in 1635. The change in declination is due to changes in the earth's magnetic field. Gellilbrand also studied ways to improve navigation and find ways to determine longitude from celestial observations.
Although only 39 years of age Gellibrand retired in 1836 moving to Mayfield in Sussex. He died not long after, suffering a fever.
Goodwin, Gorodon; "Henry Gellibrand" in Dictionary of National Biography, 1885-1900, Volume 21; Smith, Elder, and Co.
O'Connor, JJ and Robertson, EF; "Henry Gellibrand"; MacTutor History of Mathematics Archive at www-history.mcs.st-andrews.ac.uk
Henry Gellibrand Wikipedia Entry
Sunday, September 15, 2013
He returned to the United States in 1905 to a faculty position at the Massachusetts Institute of Technology, where he was appointed assistant professor in 1907, associate professor in 1908, and full professor in 1911. In 1912 he left M.I.T. for the University of California at Berkeley where he was dean of chemistry and a professor of physical chemistry. His time in California was interrupted by First World War when Lewis served as a major in the gas service and chemical warfare service.
His first research interest was thermodynamics. He introduced the idea of activity, or the effective concentration of a chemical species in solution. Lewis is best remembered for his valence theory and the eponymous dot structures. Lewis pictured atoms as cubes with the electrons at the corners. We now know that atoms are spherical and their electrons are spread out in orbitals. Lewis also wrote papers on relativity and defined acids and bases as electron acceptors and electron donators respectively. Lewis was the first to produce deuterium oxide (heavy water) using Ernest Lawrence's cyclotron in 1933.
Honors won by Lewis include election in to the National Academy of Science in 1913. Because of his disagreements with Walther Nernst he was never awarded the Nobel Prize although he was nominated 30 times. He was awarded numerous honorary doctorates and membership in Royal Society, the Chemical Society of London and the Indian, Swedish, and Danish Academies of Science.
On March 23, 1946 Lewis died in a laboratory accident involving hydrogen cyanide which some believed was suicide.
Carey, Charles W.; "Lewis, Gilbert N." in American Scientists; Infobase Publishing; 2006
Hildebrand, Joel H.; "Gilbert Newton Lewis; 1875-1946"; National Academy Press; 1958
Gilbert N. Lewis Wikipedia Entry
Sunday, September 8, 2013
While working there she published with Dale and Wilhelm Feldberg a seminal paper in neuroscience describing how acetylcholine serves as neurotransmitter in the voluntary nervous system. Nerve impulses are sent electrically down nerves by changing the permeability of the cell membrane to sodium ions allowing them to rush in. Once the impulse reaches the end it releases acetylcholine into nervous/muscle junction. The actylcholine serves as a chemical messenger quickly diffusing across the interface and causing the muscle to contract. The next year she moved to Girton College, Cambridge, where she remained for four years. When World War II broke out she was scheduled to imprisoned as an enemy national but her colleagues came to her rescue, Dale phoning the Home Office demanding an interview with the Home Secretary. During the war she worked with John Gaddum at the College of the Pharmacological Society in London and in 1948 published another paper with Feldberg demonstrating the presence of acetylcholine using nerves in the brain. Vogt followed Gaddum to the University of Edinburgh, where she was first hired as a lecturer and then as a reader.
In 1952 she was elected to the Royal Society of London, a honor that had only been given to 8 women before her. Vogt's research now centered on amines and their use as a neurotransmitter. Later in her career her work centered on serotonin and its effects in the brain. This research lead to breakthroughs in pharmaceuticals that aids patients with depression.
Honors won by Vogt include a Roylal Medal from the Royal Society in 1981, honorary doctorates from the University of Edinburgh and Cambridge University and honorary membership in the American Academy of Arts and Sciences. She retired due to ill health at the age of 87 and moved to La Jolla, California to live with her sister.
She died on the day after 100th birthday, September 9, 2003.
Anon.; "Marthe Vogt"; The Telegraph; October 3, 2003
Bell, Chris; "Marthe Louise Vogt (1903-2003)"; pA2 Online; Vol.2 Issue 1; retrieved from: pa2online.org
Marthe Vogt Wikipedia Entry
Sunday, September 1, 2013
Folkers is best remembered for his determination of the structure of vitamin B-12, which is also called cobalamin. Vitamin B-12 is unique among the water soluble B vitamins in that it contains an atom of cobalt. Vitamin B-12 is used in DNA synthesis and regulation and also fatty acid synthesis. It is synthesized by bacteria and archea and must be ingested by higher organisms. In humans lack of vitamin B-12 causes pernicious anemia where red blood cells do not develop properly and lyse easily. With Fern Rathe and Edward Kaczka, Folkers isolated the antibiotic cathomycin in 1955.
Honors won by Folkers include the Perkin Medal in 1960 and the Priestly Medal in 1985. Folkers was elected to the National Academy of Science in 1948.
Folkers died on December 7, 1997.
Olson, Robert E.; "Karl August Folkers (1906-1997)"; Journal of Nutrition (2001)131:2227-2230
Shive, William; "Karl Augus Folkers September 1, 1906-December 7, 1997"; Biographical Memiors: National Academy Press
Karl August Folkers Wikipedia Entry
Sunday, August 25, 2013
With the election of Adolph Hitler and the rise of the National Socialist (Nazi) Party in 1933 Krebs was dismissed from his position because of his Jewish heritage. After his dismissal Krebs emigrated to England where he took a position at Cambridge University sponsored by a Rockefeller Foundation Studentship grant. In 1935 he was appointed as a lecturer in pharmacology at Sheffield University and in 1938 he was made lecturer-in-charge of Sheffield University's newly founded department of biochemistry. In 1945 the appointment was raised to a professorship and he took charge of the Medical Research Council's research unit established at the university. In 1954 he was appointed as the Whitley Professor of Biochemistry at Oxford University.
Krebs' major research accomplishment was elucidating the citric acid cycle (also called the Krebs cycle or the tri-carboxcylic acid cycle.) The citric acid cycle, which takes place in the mitochondrial matrix (inside the mitochondrial inner membrane) in eukaryotes and in the cytosol of prokaryotes, is a cyclic reaction cycle that produces reduced equivalents that are used to produce cellular energy. It is the final set of reactions of cellular metabolism by which organisms break down carbohydrates producing energy and releasing carbon dioxide (for a video showing the series of reactions by which carbohydrates are broken down, highlighting the citric acid cycle, to make cellular energy see here). For his discovery of the citric acid cycle Krebs shared the 1953 Nobel Prize in physiology and medicine with Fritz Lipmann.
Other honors won by Krebs include a knighthood in 1958 and election as a honorary fellow of Girton College, Cambridge University in 1979.
Krebs died on November 22, 1981.
Stubbs, Marion and Gibbons, Geoff; "Hans Adolph Krebs (1900-1981)...His Life and Times"; IUBMB Life (2000)50:163-166
Hans Krebs Nobel Biography
Hans Adolph Krebs Wikipedia Entry