Sunday, December 29, 2013

Carl Ludwig

Karl Friedrich Wilhelm Ludwig was born on December 29, 1816 in Gottingen, Germany. His father had been on officer in the Napoleonic Wars. Ludwig graduated high school in 1834 and started his medical studies at the University of Marburg. He was relegated from the university because of his political activities and he continued his medical studies at the University of Erlangen and at the School of Surgery at Bamberg. He returned to Marburg in 1839 and finished his medical doctorate in 1840. After graduation he worked in the laboratory of Robert Bunsen and as a prosector in the school of anatomy at the University of Marburg. In 1846 he was appointed professor extrordinary in anatomy at Marburg and in 1849 he was appointed professor of anatomy at the University of Zurich. Six years later he went to Vienna and and an appointment teaching at the Josephinium, a school for military surgeons. In 1865 he took a position at the newly created department of physiology at the University of Leipzig. In 1869 he was called to develop and be the director of the newly created physiological institute at Leipzig that would eventually be named after him. He remained there until his death.

Ludwig's research dealt with the circulation of fluids in the body. His first paper, published in 1842, described the circulation of blood in the kidney and was the first to describe the function of the glomerulus. He also investigated blood pressure and designed an instrument to measure and record it. His investigations also included secretory glands and lymph circulation. More important than any of his research results it was his methods that had a lasting impact on the study of physiology. Up until the time of Ludwig physiological research involved the belief in vital forces, forces generated by the body that sometimes went against physical law. Ludwig's insight was that the forces of physics and chemistry played a important role in physiological processes and his methods sought to show how these natural processes affected physiological systems. For his insights and use of methods he is often called the father of modern physiology.

Honors won by Ludwig include the Copley Medal in 1884, given by the Royal Society of London and foreign membership in the Royal Swedish Academy of Science in 1869.

Ludwig died on April 23, 1895.


References:

Zimmer, Heinz-Gerd; "Carl Ludwig"; retrieved from feps.org

"Carl Ludwig" in the 1911 Encyclopedia Britannica

Carl Ludwig Wikipedia Entry

Saturday, December 21, 2013

Grote Reber

Grote Reber was born on December 22, 1911 in the Chicago suburb of Wheaton, Illinois. His father was a lawyer and the part owner of a canning factory. He died when Reber was 21. His mother was an middle school teacher and had among her students Edwin Hubble, who her son would later discuss cosmology with. Reber earned a degree in electrical engineering from the Armour Institute of Technology (now the Illinois Institute of Technology) in 1933. Reber excelled at mathematics and electronics and after graduation he worked a series of jobs at Chicago area radio manufacturers.

In his spare time Reber was an amateur radio enthusiast and after contacting 150 countries with his radio he was looking for a new challenge. He read about Karl Jansky who had discovered cosmic radio emissions coming from the region of the constellation Sagittarius. Reber took the summer of from his engineering job and used $2000 of his own money (the equivalent of  his annual salary) to build a 32 foot parabolic radio radio antenna in the vacant lot next to his mother's house. After series of failures in 1939 Reber was able to detect galactic radio emissions and used his antenna to make maps of the radio emissions from the sky. Reber was forced to make his observations during the night and early morning hours due to interference from automotive starters. In 1943 Reber detected radio emissions from the sun.

After his mother died in 1945 Reber accepted a position working for the National Institute of Standards in Washington D.C., but he soon grew frustrated with the growing atmosphere of McCarthyism in the nation's capital. In 1951 he moved to Hawaii, where he researched astronomy and atmospheric physics at an observatory at the top of Haleakala, a volcanic peak on Maui. In 1954 Reber moved to Tasmania, where he could exploit the ionospheric transparency for his studies.

Initially Reber had trouble getting his articles published. Reber was a pioneer in the field of radio astronomy and it took a while for his findings to be accepted. Today radio astronomy is a major field of study. Awards won by Reber include the Cresson Medal given by the Franklin Society and the Bruce Medal awarded by the Astronomical Society of the Pacific. He was also awarded an honorary doctorate by Ohio State University.

Reber died on December 20, 2002 in Tasmania, Australia, two days before his 91st birthday.


References:

Kellermann, Kenneth; "Grote Reber, 1911-2002"; Bulletin of the American Astronomical Society(2003)35:1472-3

Tyson, Anthony J., "Grote Reber"; Physics Today; August 2003

Grate Reber Wikipedia Entry

Sunday, December 15, 2013

Henri Becquerel

Henri Becquerel was born on December 15, 1852 in Paris, France. He was born into a family of scientists. His grandfather, Antoine Cesar Becquerel, invented an electrolytic method for extracting metals from their ores and his father, Alexander Edmund Becquerel, a professor of applied physics was known for his work on solar radiation and phosphorescence. Becquerel attended the Ecole Polytechnique in 1872 and the Ecole des Pontes at Chaussees from 1874 to 1877 where he studied engineering. After graduation he worked as a engineer for the Department of Bridges and Highways. In 1876 he became an assistant teacher at the Ecole Polytechnique. In 1895 he became the chair of physics. He also worked as an assistant naturalist at the Museum of Natural History. When his father died in 1891 he assumed his position as the professor of physics at Museum of Natural History.

Becquerel's research covered a number of physics topics. His first work was the rotation of polarized light rays using magnets. Next he began researching phosphorescent materials following in the footsteps of his father. He studied phosphorescent materials by exposing them to sunlight and then exposing them to photographic plates. He was conducting an experiment with uranium. First he would expose it to sunlight and them place it in with a photographic plate. He noticed that the uranium fogged the picture produced. He found he could block the fogging by inserting coins between the uranium and the photographic plate. An experiment run on February 27 and 28, 1896. The weather was overcast when he exposed his uranium salts and so he expected only a faint fogging on the developed photographic plate. Instead he was surprised to find the fogging as severe as it would be from uranium exposed to the sun. This radiation produced by the uranium did not need to be illuminated with sunlight to be produced. The new rays that were produced by the uranium were named Becquerel rays.

Becquerel determined that the rays ionized gasses and could be bent by a magnetic field, unlike x-rays which had recently been discovered by Wilhelm Rontgen. Becquerel determined that the particles emitted by the uranium salts were identical to the electrons discovered by Joseph John Thomson. Becquerel named the particles beta particles. For his discovery of spontaneous radioactivity Becquerel shared the 1903 Nobel Prize in physics with Marie and Pierre Curie. Becquerel had given the breakdown products of his uranium salts to the Curies, who discovered polonium and radium in them. Other honors won by Becquerel include election to French Academy of Sciences in 1889. He was made an officer in the Legion of Honor in 1900.

Becquerel died on August 25, 1908.


References:

Steinman, Rebecca; "Henri Bequerel"; in Biographies of Atomic Scientists

Henri Becquerel Nobel Biography

Henri Becquerel Wikipedia Entry




Sunday, December 8, 2013

Jan Ingenhousz

Jan Ingenhousz was born on December 8, 1730 in Breda, Netherlands. His mother died when he was young, but not much else is known about his parents, but they did have enough resources to provide Ingenhousz with a good education, including the Latin School in Breda, which he finished at sixteen and went on to study medicine at the University of Leuven, where he earned his medical doctorate in 1753. After finishing his doctorate he spent two more years attending lectures at the University of Leiden and returned to Breda to open a practice.

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.


References:

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

Martin Rodbell

Martin Rodbell was born on December 1, 1925 in Baltimore, Maryland. He was the son of a grocer and attended public schools including an accelerated program and Baltimore City College. In 1943 he went to John Hopkins University where he studied biology and French existential literature. His studies at John Hopkins where interrupted by World War II, when he served in the U.S. Navy as a radio operator in the South Pacific. He graduated with his bachelors in 1949, spending his last year taking all the advanced chemistry courses offed by Hopkins. In 1950 he went to the University of Washington where he earned his doctorate under Donald Hanahan, completing a thesis on the metabolism of  lecithin in the liver. Lecithin is a mixture of phospholipids that acts as a surfactant and lubricant.

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.


References:

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

Henry Gellibrand


Henry Gellibrand was born on November 17, 1597 in Aldersgate, London, England. He was the first of five sons of Henry Gellibrand, a fellow of All Souls College, Oxford. The year after the death of his father he began studying at Trinity College, Oxford, where he earned two arts degrees, a BA in 1619 and a MA in 1623. Gellibrand took holy orders and served as a curate in Chiddingstone, Kent. In 1626 he became professor of astronomy at Gresham College, London upon the recommendation of Henry Briggs. When Briggs died in 1630 he left his unfinished Trigometria Britanica to Gellibrand. Gellibrand finished the manuscript and published in 1633.

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.


References:

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

Gilbert Lewis

Gilbert Newton Lewis was born on October 23, 1875 in Weymouth, Massachusetts. His father, Francis Lewis, was a lawyer. When he was nine his parents moved to Lincoln, Nebraska. Lewis had no formal schooling until he was admitted to a preparatory school for the University of Nebraska at the age of 13. He attended the University of Nebraska for two years, then in 1893 he went to Harvard College where he graduated in 1896. After a year of teaching at Philips Academy Andover outside of Boston he returned to Harvard where he earned his MA in 1898 and his PhD in 1899 with a dissertation on electrochemical potentials. He remained at Harvard for on more year as an instructor then went on a traveling fellowship where he visited Wilhelm Ostwald in Leipzig and Walther Nernst in Gottingen. When he returned he spent three more years at Harvard before moving the the Philippines where he was superintendent of weights and measures and chemist at the Bureau of Science.

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.


References:

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

Marthe Vogt

Marthe Louise Vogt was born on September 8, 1903 in Berlin, Germany. Her parents, Cecile and Oskar, Vogt were leading neuroanatomists and an interest in neural research started early with Vogt. She earned a medical doctorate and a PhD in chemistry from the University of Berlin. Vogt worked as an assistant to Otto Trendelenburg at the Berlin University pharmacology department starting in 1930. A year later she was appointed as head of the chemistry department of the Kaiser Wilhelm Institute. In 1933, with the election on Hitler, Vogt decided to emigrate to the United Kingdom. Although she was not Jewish, with the rise of Hitler she felt she must leave Germany. In 1935 she got a Rockefeller Travelling Fellowship at the National Institute for Medical Research in the laboratory of Sir Henry Dale.

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.


References:

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

Karl August Folkers

Karl August Folkers was born in Decatur, Illinois on September 1, 1906. His father August William Folkers was born in Germany and had emigrated to the United States with his parents and married Laura Susan Black in 1904. As Folkers grew up he became interested in chemistry and obtained chemistry sets to experiment with. He attended the local public schools and he attended the University of Illinois at Urbana-Champagne where he earned a BA in chemistry studying under Carl Marvel in 1928. Folkers earned a PhD under Homer Atkins at the University of Wisconsin with a dissertation on using catalysts to reduce esters into alcohols. Folkers did post-doctorate work under Treat Johnson at Yale University studying biochemistry. In 1934 Folkers joined the pharmaceutical company Merck. In 1939 Folkers became the assistant director of research at Merck.

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.


References:

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

Sir Hans Adolph Krebs

Hans Adolph Krebs was born on August 25, 1900 in Hildesheim, Germany. He was the second child of Georg Krebs, an ear/nose/throat doctor and a biochemist, and his wife Alma. Krebs attended the local grammar school and was briefly conscripted into the German imperial army at the end of World War I. Krebs then studied medicine at the University of Gottingen and the University of Freiburg, and earned his PhD from the University of Hamburg in 1925. He studied chemistry in Berlin for a year and then took a job as an assistant to Otto Warburg at the Kaiser Wilhelm Institute for Biology. He remained there until 1930 when, after briefly doing clinical work in Altona, Germany, he returned to the University of Freiburg, where working with Kurt Henseleit he described the urea cycle, which take place in the mammalian liver. The urea cycle is how mammals remove ammonia (which is toxic in large amounts), from amino acid metabolism, converting it into urea which is excreted by the kidneys.

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.


References:

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


Sunday, August 18, 2013

Julius Lothar Meyer

Julius Lothar Meyer was born on August 19, 1830 in Varel, which at the time was part of the Dutchy of Oldenburg, and is now part of Germany. He was the fourth of seven children of a physician and his wife. He began his education with the intention of following his father in his career choice and after high school he studied medicine first at Zurich University and then at the University of Wurzburg. He qualified in medicine in 1854. After graduation, interested in physiological chemistry, Meyer worked at the University of Heidelberg, where Robert Bunsen was the chemistry department chair. He earned his Ph.D. from the University of Breslau in 1858, completing a thesis on the action of carbon monoxide on blood. The following year he became a privat-docent in physics and chemistry at Breslau. In 1866 Meyer became professor of chemistry at Karshule Polytechnic and in 1876 he became the first professor of chemistry at the University of Tubingen, where he remained until his death.

Meyer is chiefly remembered for his contributions to the development of the periodic table of elements. In 1864 Meyer published Die Modernen Theorie der Chemie, a chemistry textbook that went through five editions and was translated into English, French, and Russian. Included in the book was a table of 28 elements arranged by increasing atomic mass. Meyer was the first to identify the periodic (repeating) nature of the elements. Periodicity means that chemical elements of different sizes can have similar properties and those properties are repeating in that elements listed on the periodic table in groups (vertical columns) have similar chemical properties. Meyer's publication preceded Dimitri Mendeleev's periodic table (from which the modern periodic table was developed) which was not published until 1869. Like Mendeleev's table Meyer's table has empty spaces for elements that had not been discovered yet.

Meyer is also known for being the first to predict that benzene had a cyclic shape, although he did not predict the alternating single/double bonds found in benzene, that were later described by August Kekule. In 1882, Meyer (with Mendeleev) was awarded the Davy Medal by the Royal Society of London.

Meyer died on April 11, 1895.


References:

The Royal Society of Chemistry: "Julius Lothar Meyer -- The First Identifier of Periodicity?"; retrieved from rsc.org

Daintith, John; "Meyer, Julius Lothar" in the Biographical Encyclopedia of Scientists, Third Edition; CRC Press; 2010

Scerri, Eric; A Tale of Seven Elements; Oxford University Press; 2013

Julius Lothar Meyer Wikipedia Entry


Sunday, August 11, 2013

Cato Maximilian Guldberg

Cato Maximilian Guldberg was born on August 11, 1836 in Christiania (now Oslo) , Norway. He was educated at the University of Christiania. Starting in 1860 he taught mathematics at the Royal Military School. Later he became a professor of applied mathematics at the University of Christiana.

In 1863, working in collaboration with his brother-in-law Peter Waage (with whom he is pictured above, Guldberg is on the left) he formulated the law of mass action. This is a chemical law that says that the rate of any chemical reaction is proportional to the concentration of the reacting chemical(s). So for the chemical reaction A + B -> C, the rate of the reaction will be a constant (k) times the concentrations of A and B, such that rate = k[A][B], where [A] and [B] are the concentrations of A and B. Guldberg and Waage also investigated the effects of temperature on chemical reaction rates. Because Guldberg and Waage published in Norwegian the law of mass action when first published was largely ignored. When it was republished in French it still drew little attention until it was experimentally demonstrated by William Esson and Vernon Harcourt working at Oxford University.

Starting in 1870 Gulberg investigated how a dissolved substance affects the freezing point and vapor pressure of a pure liquid. In 1890 he formulated Guldberg's law which says that the boiling point of a liquid is two thirds the temperature of its critical temperature, the temperature at which a gas cannot be liquefied by increased pressure alone.

Gulberg died on January, 14, 1902 in his native city, which had respelled it's name to Kristiania.


References:

Daintith, John; "Guldberg, Cato Maximilian (1836-1902)" in Biographical Encyclopedia of Scientists, Third Edition; CRC Press; 2010

Tilden, Sir William Augustus; "Cato Maximilian Guldberg" in The Progress of Scientific Chemistry of Our Times; Longmans, Green; 1913

Cato Maximilian Guldberg Wikipedia Entry

Sunday, August 4, 2013

John Wrottesley, Second Baron Wrottesley

John Wrottesley was born on August 5, 1798, near Woverhampton, in central England. Wrottesley was the eldest son of Sir John Wrottesley and his first wife Lady Carolyn Bennet. Wrottesley attended Westminster School from 1810 to 1814. He graduated first class in mathematics from Corpus Christi College, Oxford in 1817. He began building an observatory in Blackheath in 1829 and began making observations in 1831 cataloging the right ascensions of 1318 stars.

Because the celestial sphere of stars are stationary with respect to an orbiting and rotating Earth their position in the sky can be measured using a system of two coordinates, right ascension and declination. Right ascension is measured in hours and minutes and is the equivalent of terrestrial longitude on the celestial sphere. The other coordinate used identify star positions used with right ascension is declination. This is the angle in degrees from the equator of the celestial sphere that a star is. The equator of the celestial sphere is directly above the Earth's equator. For his catalog of stars' right ascensions Wrottesley was awarded a gold medal by the Royal Astronomical Society in 1839.

Wrottesley inherited his father's title as Baron Wrottesley in 1841. With his elevation to Baron he moved his observatory from Blackheath to his new home at Wrottesley Hall. He served as president of the Royal Astronomical Society from 1841 to 1842. He served as president of the Royal Society from 1854 to 1858. A crater on the moon is named after Wrottesley.

Wrotteseley died on October 17, 1867.


References:

Anon.; Obituary; Monthly Notices of the Royal Astronomical Society (1867)28:181-185

Carlyle, Edward Irving; "Wrottesley, John 1798-1867"; in Dictionary of National Biography 1885-1900 Vol. 63. Retrieved from: en.wikisource.com

John Wrottesley, Second Baron Wrottesley Wikipedia Entry


Saturday, July 27, 2013

Baruch S. Blumberg

Baruch Samuel Blumberg was born on July 28, 1925 in Brooklyn, New York. His father, Meyer Blumberg, was a lawyer. Blumberg attended Yeshivah of Flatbush a parochial elementary school where he learned to read and write Hebrew. He attended Far Rockaway High School. In 1943 he joined the U.S. Navy where he served as a deck officer on landing ships, completing a undergraduate physics degree while he was in the Navy. He retired from the Navy in 1946. After leaving the Navy he began graduate work in mathematics at Columbia University. After a year studying math, he switched to medicine, at the urging of his father. he earned his MD in 1953 and remained at Columbia for his internship and residency working at Bellevue Hospital . He then went to Balliol College, Cambridge where he studied biochemistry, earning a PhD in 1957.  He was the first American to become a master of Balliol College. From 1957 to 1964 he worked for the National Institutes of Health.

Blumberg's research dealt with polymorphisms in serum proteins of human blood. Polymorphisms are differences in proteins caused by different gene alleles. Alleles are different forms of the same gene. He took many trips to tropical countries to collect and study the blood proteins of people living there and studied how these differences affected the health of the their carriers. During his trips to Australia he found a unique protein in the blood of Australian aboriginal people, which he called Au. In 1966 he found a patient who had the Au protein spontaneously appear in their blood. The same patient developed hepatitis. From this result Blumberg determined that the Au protein was a surface protein for the hepatitis B virus. Using this result Blumberg and his team were able to develop a screening test and a vaccine for the Hepatitis B virus. For his discovery of the hepatitis B virus Blumberg shared the 1976 Nobel Prize in medicine with D. Carleton Gajdusek.

After winning the Nobel Prize Blumberg continued working to better understand the hepatitis B virus, including its affects on individuals carrying the virus. In 1994 Blumberg was elected fellow of the American Academy of Arts and Sciences and he served from 1999 to 2002 as the first director of the NASA Astrobiology Institute.

Blumberg died of an apparent heart attack on April 5, 2011, while he was attending a conference at NASA's Ames Research Center in Mountain View, California.


References:

Blumberg, Baruch, Nobel Autobiography, at nobelprize.org

Rall, Glenn; Baruch S.Blumberg MD,1925-2011; Virology Blog at virology.ws

Baruch S. Blumberg Wikipedia Entry


Sunday, July 21, 2013

Georg Brandt

Georg Brandt was born on July 21, 1694 in Riddarhyttan, Sweden. His father, Jurgen Brandt, was a metalworker and an apothecary. Growing up he assisted his father with his metalwork projects and he became interested in it. Brandt attended Uppsala University and worked for the council of mines. In 1721 he traveled to Leiden where he worked in the laboratory of Herman Boerhaave for three years. There he studied chemistry and medicine. He earned a medical doctorate from the University of Rheims in 1726. When he returned home to Sweden he was made the director of laboratory of the Council of Mines. Brandt was named warden of the Royal Mint in 1730. He became an associate member of the council of mines in 1747 and a full member in 1750.

Brandt's research involved investigating metals. He coined the term semi-metals to describe elements that have both metal and non-metal characteristics. These elements are now called metalloids. Metaloids are the elements in the region between metal and non-metal elements on the periodic table (see here) In 1733 he investigated arsenic and its compounds. In 1735 he postulated that the blue color in an ore known as smalt was due to an unknown metal or semi-metal. In 1742 he was able to isolate this unknown blue metal which he named cobalt, taking the name from the old Teutonic word kobold meaning demon. Cobalt is atomic number 27 and is represented by the chemical symbol Co.

Brandt's later research involved using hot acid solutions to dissolve gold. Brandt's later publications dealt with criticism of the alchemical belief that other "base" metals could be transformed into gold. It has been said that he did more than any other chemist to clarify that transmutation of other metals into gold was impossible and that claims of alchemists that they could create gold from other metals were false.

Brandt died on April 29, 1768 in Stockholm, Sweden of prostate cancer.


References:

Morris, Richard; The Last Sorcerers; Joseph Henry Press; 2003

"Brandt, Georg" in Complete Dictionary of Scientific Biography; Charles Scribner's Sons; 2008

Georg Brandt Wikipedia Entry


Sunday, July 14, 2013

Jean-Baptiste Dumas

Jean-Baptiste-Andre Dumas was born on July 14 (Bastille Day), 1800 in Ales, France. His father worked as a clerk in the municipality of Ales. Initially his family prepared him for a naval career, but with the bloodshed that followed the downfall of the Napoleonic empire he was apprenticed to an apothecary. Wishing to leave his home in 1816 he traveled to Geneva on foot, where he attended lectures on science. The apothecary where he worked provided a laboratory where he could perform experiments. In 1821 Dumas went to Paris where he completed his studies in chemistry. Two years later Dumas was appointed lecture assistant to Louis Jacques Thenard, a professor at the Ecole Polytechnique.  Dumas succeeded him two years later.

During the 1820s Dumas developed a method of measuring the vapor densities of volatile liquids which he used to measure the atomic weights of 30 of the 59 the elements known at the time. Starting with the hypothesis of William Prout, that the atomic mass of hydrogen was 1 and all the other elements were multiples of hydrogen's mass, Dumas determined the masses of the other elements. Later Dumas began work on organic chemistry (chemistry involving compounds of carbon) going on to become one of the most advanced organic chemists of his time. In 1833 Dumas developed a method for determining the amount of nitrogen in an organic compound, founding modern analytical chemistry.

Dumas also studied physiological questions. In one of his first researches he determined that iodine was what was necessary factor to treat goiter. He also determined that kidneys removed urea, a form of nitrogen waste, from the blood.

When he reached middle age Dumas devoted more of his time to public service and less time to scientific research. He served as the minister of agriculture and commerce and as director of the mint. He was also served as a senator.

Dumas died on April 10, 1884 in Cannes. He was buried in Paris and his is one of the 72 names memorialized on the Eiffel Tower.


References:

Anon; Obituary; Proceedings of the Royal Society; (1884) 37:X

Cooke, Josiah Parsons; "Jean-Baptiste-Andre Dumas"

Newbold, Brian; "Jean-Baptiste-Andre Dumas: A Dominating Influence in Nineteenth Century French Chemistry";

Jean-Baptiste Dumas Wikipedia Entry

Monday, July 8, 2013

Nettie Stevens

Nettie Maria Stevens was born on July 7, 1861 in Cavendish, Vermont. Her family settled in Westford, Vermont, where her father was a carpenter and handyman. He did well enough that he was able to invest in real estate and he was able to send his children away to school. Stevens attended Westfield Academy and Westfield Normal School where she completed a four year program in two years. After working as a teacher for a while, in 1896 Stevens began attending Stanford University, in Palo Alto, California, where she earned a BA in 1899 and a MA in 1900 completing her thesis using a microscope to describe new species of marine life. Stevens next went to Bryn Mawr College where she studied cytology. While at Bryn Mawr Stevens won a fellowship that allowed her to travel to Warzburg, where she studied in the laboratory of Theodore Boveri. Boveri was studying the role that chromosomes have on heredity. Stevens returned to Bryn Mawr finishing her PhD in 1903. After finishing her doctorate she remained at Bryn Mawr as an assistant.

Stevens research while at Bryn Mawr was studying the chromosomes of sex cells of meal worms. Sex cells are the cells produced by males and females that give rise to progeny. These cells have half the number of chromosomes that normal cells do. When male and female sex cells combine, a process called fertilization, it gives rise to a single cell with half of its chromosomes from the father and half from the mother that will eventually develop into progeny. Stevens noted in her research that some male sex cells have a chromosome not found in female sex cells. She proposed that this extra chromosome was responsible for determining the sex of the offspring. Today we call this extra chromosome the Y-chromosome and when a male sex cell, with a Y-chromosome, fertilizes an egg the offspring will be male. Half of male sex cells have an X-chromosome and when it fertilizes a female sex cell the offspring will be female. At the time it was believed that the gender of offspring was determined by the mother and environmental factors and Stevens' research was not widely accepted. Today we know that the sex cells of the father, with either Y or X chromosomes, determine the gender of the offspring through the mechanism discovered by Stevens.

Stevens died of breast cancer on May 4, 1912 at the early age of 39.


References:

DNA Learning Center; "Nettie Maria Stevens (1861-1912)"; Retrieved from: dnaftb.org

Scitable; "Nettie Stevens: A Discoverer of Sex Chromosomes"; Retrieved from: nature.com

Nettie Stevens Wikipedia Entry

Monday, July 1, 2013

Lawrence J. Henderson

Lawrence Joseph Henderson was born on June 3, 1878 in Lynn, Massechusets. His father Joseph was a businessman. Henderson went from being an undersized infant to an athlete who was known for his running speed. Henderson attended school in Salem, Massachusetts and entered Harvard College at the age of 16. He was fond of mathematics and physics and did well in those subjects. He earned his A.B. degree in 1898 and entered Harvard Medical School later that year. He earned his MD in 1902 and afterwards spent two years working in Franz Hofmeister's laboratory at the University of Strasbourg. When he returned to the United States he took a lecturer position at Harvard Medical School. He would remain at Harvard for the rest of his career, as an instructor from 1905-1910, as an assistant professor of biological chemistry from 1910-1919, as a professor from 1919-1934 and as the Abbot and James Lawrence professor of biological chemistry from 1934 until his death.

Henderson's initial research interest upon returning to America was in understanding buffer systems and how the human body maintains its pH balance. In the blood carbon dioxide from cellular respiration combines with water to form carbonic acid. Carbonic acid (H2CO3) exists in the blood primarily in the form of bicarbonate (HCO3-). Bicarbonate and the proteins of the blood act as buffers that maintain the body's pH. When excess acid or base is produced bicarbonate acts to maintain the body's pH at a slightly basic pH (about 7.35). From his research on buffers Henderson developed an equation that can be used to calculate the pH of a buffer system. The Henderson/Hasselbalch equation equates the pH to the pKa of the acid in the buffer plus the log of the concentration of the acid's anion divided by the concentration of the associated acid (pH = pKa + log([A-]/[HA]).

Henderson's later research career dealt with more philosophical issues in science. He published two books, The Fitness of the Environment and The Order of Nature, devoted to the discussion of global problems of the fitness of organisms in their environments. In The Order of Nature he concluded that "the whole evolutionary process, both cosmic and organic, is one, and the biologist may rightly regard the universe, in its essence as biocentric."

Henderson died on February 10, 1942 in Cambridge, Massachusetts.


References:

Cannon, Walter M.; "Biographical Memoir of Lawerence Joseph Henderson 1878-1943"; National Academy Press; 1943

Mayer, Jean; "Lawrence J. Henderson - A Biographical Sketch"; The Journal of Nutrition (1968)94:3-5

Smith, Charles H.; "Henderson, Lawrence Joseph (United States 1878-1942)"; retrieved from: http: wku/people.wku.edu/charles.smith

Lawerence Joseph Henderson Wikipedia Entry


Sunday, June 23, 2013

Johannes Wislicenus

Johannes Winlicenus was born on June 24, 1835 in Kleineichsted, Saxony, the son of Gustav and Emilie Winlicenus. He was born into a devout protestant family that in the 17th century had been forced to flee their native Poland to Saxony on account of their religion. His father was a protestant minister who in 1853 published a book in which he attempted to liberate people from what he thought was a "superstitious adoration" of the Bible. The book was considered blasphemous by the authorities, and so it was destroyed and he was sentenced to two years in prison. Instead he fled with his family to Boston, Massachusetts. Johannes who was 18 at the time served as an assistant to chemist Eben Horsford at Harvard University and in 1855 he as appointed lecturer at New York's Mechanic's Institute. Returning to Europe in 1856 he went to the University of Halle where he resumed his studies and served as an assistant to Wilhelm Heintz. He had finished the requirements for his PhD by 1859 but as a condition of his graduation he was asked to renounce the teachings of his father and cease his political activities. He refused and then went to the University of Zurich where he finished his doctorate in 1860. He served as a lecturer at the University of Zurich until 1868 when he became a professor of chemistry there. In 1860 he became professor of chemistry at the Swiss Pyrotechnical Institute and he served both professorships simultaneously. In 1872 he became the chair of chemistry at the University of Wurzburg and in 1885 he became a professor of chemistry at the University of Leipzig.

Winlicenus' research was in organic chemistry. Starting in 1868 he began studying lactic acid. Lactic acid is a  carboxylic acid that is a metabolite of glucose. In his studies he found that there were two types of lactic acid which had different chemical properties. While these two chemicals have the same chemical formula (the same numbers and types of atoms) they have different structures. In the case of lactic acid (a three carbon long carboxylic acid) one form has a hydroxyl group attached to the carbon adjacent to the carbonyl carbon and the other form has a hydroxyl group attached to the terminal carbon, the carbon on the opposite end of the three carbon chain from the carbonyl. Because these two molecules have different structures they have different properties, but the formulas for both compounds are both C3H6O3. Winlicenus called these chemicals with the same formula but different structures structural isomers.

Another important experiment carried out by Winlicenus, working in collaboration with his friend Aldolf Fick a professor of physiology at the University of Zurich, showed that carbohydrates and fats were the principal source of muscular energy. The pair ascended the Faulhorn, taking with them only food from which proteins had been excluded. While they climbed the pair monitored their nitrogen metabolism and found that the the break down of proteins accounted for less than one third of the energy generated by their metabolism.

Wislicenus was elected a foreign member of the British Royal Chemical Society in 1888 and member of the Royal Society of London in 1897 which presented him with its Davy Medal in the following year.

Winlicenus died on December 5, 1902.


References:

P.F.F.; "Johannes Wislicenus. 1835-1902"; Proceedings of the Royal Society (1907) 78:iii-xii

Ramberg, Peter J.; Chemical Structure, Spatial Arrangement: An Early History of Stereochemistry. 1874-1914; Ashgate Publishing Ltd.; 2003

"Johannes Wislicenus, Biography", retrieved from: my.rsc.org

Johannes Wislicenus Wikipedia Entry

Sunday, June 9, 2013

Giovanni Cassini

Giovanni Domenico Cassini was born in Perinaldo in northern Italy on June 8, 1625. He was brought up by his maternal uncle who looked after his education. He attended school in Valebone for two years and then attended the Jesuit college in Genoa where he studied astrology and astronomy. Although he studied astrology he admitted that it was not prophetic but at the time there was little separation between astronomy and astrology. In 1644 he was invited to become an assistant at the Bologna Observatory and six years later, when he was still only 25, he was made professor of astronomy and mathematics at the University of Bologna. In addition to his astronomical work, Cassini also did river engineering work and engineered fortifications for the Holy See. In 1668 he was invited to help set up the new Paris Observatory by Louis XIV of France. Pope Clement IX agreed to the trip believing it would be short, only two years at the most. Cassini once established in the new observatory made no effort to return to Italy. He remained at the Paris Observatory and three generations of his descendants ran it until 1794.

Cassini is probably best remembered for discovering the Cassini Division, a open space between Saturn's A and B rings. Before Cassini it was believed that the rings of Saturn were one large solid ring structure orbiting the planet. Cassini's observations of the rings showed that there were breaks between the rings. We know now that the rings of Saturn are not solid at all, but made up of orbiting pieces of ice and debris. Cassini was also responsible for identifying four of the moons orbiting Saturn: Iapetus, Rhea, Tethys, and Dione. Cassini also shares credit for discovering the red spot on Jupiter with English scientist Robert Hooke Although Cassini initially believed in a geocentric model for the solar system he eventually came to believe in a solarcentric model, similar to that proposed by Nicolas Copernicus.

In addition to craters on the moon and Mars named after him Cassini also has an asteroid named after him. Additionally NASA's unmanned probe that is currently exploring Saturn and its moons is named after him (for more information on the Cassini probe see here).

As he grew older Cassini's vision failed him and his son Jacques began to run the Paris Observatory. Cassini died on December 14, 1712.


References:

Connor, Elizabeth; "The Cassini Family and the Paris Observatory"; Astronomical Society of the Pacific Leaflets (1947)218:146-153

O'Connor, J.J. and Robertson, E.F.; "Giovanni Domenico Cassini"; Retrieved from: history.mcs.st-anderews.ac.uk

Giovanni Domenicao Cassini Wikipedia Entry

Sunday, June 2, 2013

Otto Loewi

Otto Loewi was born in Frankfurt, Germany on June 3, 1873. His father Jacob was a Jewish wine merchant. He attended gymnasium school in Frankfrurt and then the Universities of Munich and Strasbourg as a medical student. Not really interested in clinical medicine, Loewi applied himself to physiology and pharmacology. He completed his thesis on the effects of arsenic, phosphorus, and other substances on an isolated frog heart. After completing his medical education in 1896, Loewi spent a year as an assistant doctor in a hospital in Frankfurt. There he was frustrated by the lack of effective treatment for tuberculosis and pneumonia patients. This convinced him that he did not want to practice clinical medicine and opted instead for a research career. He was able to get a position as an assistant to Hans Meyer starting work in Meyer's laboratory in Marburg in 1898. Working in Meyer's lab he researched metabolism. While working there he proved that animals were able to synthesize proteins from protein degradation products (amino acids). Before that it was believed that animals could only make proteins from other intact proteins.

In 1903 he was appointed professor of pharmacology at the University of Graz in Austria. While working at Graz he conducted an experiment that proved that the transmission of nerve impulses to the heart was conducted by a soluble factor, the idea for which came to him in a dream. First he isolated two frog hearts, one with the vagus nerve still attached. The vagus nerve is part of the parasympathetic nervous system and causes the heart muscle to slow its beating. First he stimulated the attached vagus nerve, which caused the attached heart to slow its beating. Taking a sample of the fluid surrounding the heart with the attached nerve he applied it to the second heart. The second heart slowed its beating in response to the added fluid. Loewi named the unknown soluble factor that caused the second heart to slow its beating "vagustoff". It was later identified as acetylcholine. The transmission of nerve impulses between different neurons and at the nerve interfaces with muscles are conducted by soluble chemicals called neurotransmitters. For his pioneering work establishing the importance of neurotransmitters Loewi shared the 1936 Nobel Prize in medicine and physiology with Henry Dale. He would remain in Austria until 1938 when he was forced to leave due to the German occupation. After a brief stays in Belgium and the United Kingdom, Loewi emigrated to the United States in 1940

Other honors won by Loewi include honorary doctorates from the University of Graz, Yale University, University of New York (where he worked after he emigrated to the United States) and the University of Frankfurt. He was made an honorary member of the Physiological Society of London and a member of the Royal Society.

Loewi died on December 25, 1961.


References:

Valenstein, Elliot S.; The War of Soups and the Sparks: The Discovery of Neurotransmitters and the Dispute Over How Nerves Communicate; Columbia University Press; 2005

Otto Loewi Nobel Biography

Ottto Loewi Wikipedia Entry

Monday, April 29, 2013

Bart Bok

Bartholomeus Jan Bok was born on April 18, 1906 in Hoorn, Netherlands. His father was a sergeant major in the Dutch army and he was born on a military base, that later became a monument. After World War I, Bok's family moved to The Hague, were he went to high school. Also while living there Bok joined the Boy Scouts and he attributed his early interest in astronomy to an astronomy test given to him by a scoutmaster. Bok failed the test and afterward made an effort to study astronomy. After graduating high school he won a scholarship to study at Leiden University where he earned his bachelors, and then when to the University of Gronigen, where he earned his doctorate in astronomy. Bok then took a job working for Harlow Shapely at the Harvard Observatory. Bok worked at Harvard Observatory from 1929 to 1957. In 1957 Bok moved to Australia where he served as director of the Mount Stromlo Observatory until 1966, when he moved to the University of Arizona and the directorship of the Steward Observatory.

Bok's research at Harvard involved mapping stars of the Milky Way galaxy. He also was involved with radio astronomy, and turned Harvard into a center for radio astronomy with the installation of Agassiz Station, which he engineered. Bok worked with his wife, Priscilla, who was also an astronomer. The pair wrote a popular book about the Milky Way that went through six printings. Bok is probably best remembered for his study of dark globular clouds. These globular clouds composed of hydrogen and dust range in mass between 2 and 50 solar masses and are light years across. Bok theorized that these clouds could be the site of stellar formation. Star formation occurs when gravity collapses a cloud of hydrogen gas so compactly that a fusion reaction begins, converting hydrogen into helium and releasing energy. Bok's prediction has been proven to be correct and consequently these dark globular clouds are called Bok globules.

Awards won by Bok during his career include the Bruce Medal, from Astronomical Society of the Pacific. Bok served as president of the American Astronomical Society from 1972-74. He and his wife also have a lunar crater and an asteroid named after them.

Bok died on August 5, 1983 of a heart attack.


References:

Graham, J.A., Wade, C.M, and Price, R.M.; "Bart J. Bok: 1906-1983"; in Biographical Memiors; National Academy Press; 1994

Lada, C.J.; "Obituaries: Bart Bok"; Quarterly Journal of the Royal Astronomical Society (1987)28:539

Interview of Bart J. Bok by David Devorkin on May 15, 1878; Retrieved from aip.org




Wednesday, April 24, 2013

Sir Harold Jefferys

Harold Jeffrys was born April 21, 1891 in the village of Fatfield, near the city Sunderland, England, where his father was a schoolmaster and his mother a school teacher at the village school. He attended school in Fatfield and he was awarded a scholarship to study at Rutherford University in Newcastle-upon-Tyne. In 1907 he went to Armstrong College, also in Newcastle graduating in 1910 with distinction in mathematics. He then went to St. John's College, Cambridge earning on of four mathematical scholarships. He became a fellow at St. John's in 1914 and remained there throughout his career.

Jefferys' studies encompass many related fields, including astronomy, pure mathematics, and geophysics. He was particularly interested in seismology and using the records of earthquakes to discern information about the structure of the Earth. By studying the rates at which seismic waves travel through the Earth's crust he was able to determine that it is composed of at least two layers and that the Earth has a molten core. We now know that the Earth's core has molten outer core and a solid inner core. Although his studies advanced our knowledge of the structure of the Earth he remained skeptical of the theory of plate tectonics, the currently accepted theory of movements of the Earth's crust. Much of Jeffrey's work was completed before the advent of artificial satellites and deep ocean drilling used to do geophysical research today.

Jeffery's work in astronomy focused on the planets Neptune and Uranus. In 1923 he proposed that these planets would have surface temperatures of the order of -120 Celsius. This was disputed at the time, but has been proven accurate. He also published a book on probability theory that was influential in that field. Honors won by Jeffry's include election to the Royal Society in 1925, a Gold Medal from the Royal Astronomical Society in 1937 and the Copely Medal from the Royal Society in 1961. He was knighted in 1953.

Jeffrys died on March 18, 1989.


References:

O'Connor, J.J. and Robertson, E. F.; "Harold Jeffrys"; retrieved from history-mcs.st-and.ac.uk.

Mumford, George S.; "Jeffrys, Harold"; in Biographical Encyclopedia of Astronomers; Springer; 2007

Harold Jeffrys Wikipedia Entry

Sunday, April 14, 2013

Alan MacDiarmid

Alan Graham MacDiarmid was born in Masterton, New Zealand on April 14, 1927. His was one of five children. His family was poor and his father, an engineer was unemployed during the great depression of the 1930s. The family moved to Lower Hutt, closer to Wellington where work was believed to be more plentiful. MacDiamid became interested in chemistry as a child from reading his father's chemistry text and books he checked out from a local library. During a Guy Fawkes Day celebration he produced his own fireworks. After attending Hutt Valley High School, he entered Victoria University in Wellington in 1943. He took work there as a lab boy and finished his BSc in 1947. He remained at Victoria University as a graduate student, finishing his MSc. He attended the University of Wisconsin Madison on a Fullbright Fellowship, earning a MS in 1952 and a PhD in 1953. He earned a second PhD from Sidney Sussex College, Cambridge in 1955. After finishing his second doctorate he was a member of the junior faculty for a year at the University of St. Andrews and then became a professor at the University of Pennsylvania, were he remained for the majority of his career. In 2002 he joined the faculty at the University of Texas, Dallas.

MacDiarmid's research focused on the chemistry of silicon and non-metallic conductors. Metals (elements in the metallic region of the periodic table) are good conductors of electricity. Non-metallic elements, such as carbon, do not conduct electricity. (see here for an blog post on metal and non-metal elements) Mac Diarmid's lab developed carbon polymers that were able to conduct electricity. They developed polyacetylene, a carbon polymer, that was able to conduct electricity.  They determined that the reason the normally non-conductive carbon polymer was able to conduct electricity  were due to impurities, such as the catalyst used to create the polymer. They learned to "dope" the polymers they created, creating polymers that had widely ranging electrical conductivities. Since their discovery conductive polymers have been developed and used to make electrical capacitors that could be used as environmentally friendly batteries. For his work discovering conductive polymers, MacDiamid shared the 2000 Nobel Prize in chemistry with Alan Heeger and Hideki Shirakawa.

Other honors won by MacDiamid include the Rutherford Medal from the Royal Society of New Zealand, the American Chemical Society's materials award, and the Order of New Zealand.

MacDiamid died on Febrary 7, 2007.


References:

Callaghan, Paul: "MacDiamid, Alan Graham: 1927-2007"; in the Dictionary of New Zealand Biography retrieved from www.teara.nz.gov

MacDiamid, Alan; Nobel Autobiography

Alan MacDiamid Wikipedia entry


Monday, April 8, 2013

Edwin G. Krebs

Edwin Gerhard Krebs was born on June 6, 1918 in Lansing, Iowa. He was the son of a Presbyterian minister, William Carl Krebs, and Louise Helen (Stegman) Krebs, who was a schoolteacher before she married. Krebs' family moved many times during his youth as his father took different ministry positions. Krebs' father died when he was sixteen and a freshman in high school. After his father's death the family moved to Urbana, Illinois, where Krebs attended the University of Illinois majoring in chemistry. He earned a scholarship to Washington University in St. Louis, Missouri, where he studied medicine. After completing a 18 month residency and serving as a medical officer in the U.S. Navy, Krebs was unable to find a clinical position. Instead he took a postdoctoral research position working in the laboratory of Carl and Gerty Cori at Washington University. In 1948 Krebs was appointed assistant professor of biochemistry at the University of Washington, where he remained until 1968. In 1968 he moved to the University of California Davis, where he served as the founding chairman of the department of biological chemistry. Krebs returned to the University of Washington in 1977.

Krebs' research involved enzymes, the protein molecules that catalyze biochemical reactions. While at the University of Washington, Krebs worked with Edmond Fisher and the pair discovered the reversible phosphorylation of glycogen phosphorylase which serves to activate the enzyme. Glycogen phosphorylase is the enzyme that removes monosacharides from glycogen (the polysacharide used to store glucose for future use) so that they can be broken down into energy. Glycogen phosphorylase exists in two forms A and B. The Cori's had found that form B is inactive unless it is in the presence of adenosine monophosphate (AMP) and that form A is active without AMP. They also knew from the experiments of the Cori's that the active A form degrades into the inactive B form. Krebs and Fischer discovered that the B form is reversibly phosphorylated (phosphate is added to the protein molecule) converting it into the A form, which causes it to be activated so that it can break down glycogen. This was the first discovery of reversible phosphorylation which is a ubiquitous mechanism that serves as a means of activating many enzymes and transducing biochemical signals. For their discovery of the regulation of glycogen phosphorylase by phosphorylzation Krebs and Fischer were awarded the 1992 Nobel Prize in medicine and physiology.

Krebs died on December 9, 2009.


References:

Fischer, Edmond H.; "Edwin G. Krebs (1918-2009)"; in Biographical Memoirs; 2010; National Academy Press

Krebs, Edwin G.; "Nobel Autobiography"

Edwin G. Krebs Wikipedia Entryhttp://en.wikipedia.org/wiki/Edwin_G._Krebs

Sunday, March 31, 2013

Robert Bunsen

Robert Whilhelm Eberhard Bunsen was born on March 31, 1811 in Gottengen, Germany. His father, Christian Bunsen was the chief librarian and a professor at the University of Gottengen where Bunsen studied chemistry earning a PhD in 1831 at the age of nineteen. After finishing his doctorate Bunsen spent three years traveling through Europe, partially at the expense of the German government during which he studied a multitude of subjects. When he returned to Gottengen he served as a lecturer in chemistry. Beginning in 1836 he taught chemistry at the Polytechnic School of Cassel, and in 1839 he was appointed professor of chemistry at the University of Marburg where he remained until 1851. After a brief stint at the University of Breslau, in 1852 he became chair of chemistry at the University of Heidelberg, where he remained until retirement in 1889.

Bunsen's early research involved compounds of arsenic. He developed the use of iron oxide hydrate to precipitate arsenate which is still used to treat arsenate poisoning. He continued his studies of arsenic at the cost of almost poisoning himself and with the loss of an eye, injured by exploding glassware. One of his most lasting contribution to science was the invention of his eponymous burner. At the time chemists used oil and alcohol lamps as a source of flame. In 1854 Bunsen had gas piped into his laboratory and when none of burners available met his needs he developed his own, that produced a colorless flame, the intensity of which could be adjusted.

Using his new burner Bunsen tested different chemicals and observed different colors and was able to detect different elements based on the colors produced. Sometimes color produced by one element would mask another and he used colored glass to mask some elements. Not satisfied with this solution, he mentioned his problem to Gustav Kirchoff, a Russian physicist and using two parts from telescopes, a prism, and a cigar box with its inside covered in black the pair made a prototype spectroscope. Using their new spectroscope Bunsen and Kirchoff quickly were able to identify different elements by their spectra. In order to find undiscovered elements Bunsen had 40 tons of mineral water evaporated and he was able to identify for the first time the alkali metal elements cesium (from the Latin ceasium, sky blue, named for its blue spectral lines) and rubidium (from the Latin rubidius, or dark red, named for its red spectral lines). Today spectroscopes are widely used in chemical analysis.

Bunsen died on August 16, 1889 in Heidelberg.


References:

Fujinaka, Pam and Kerekes, Christina; "Robert Wilhelm Bunsen (1811-1899)"; retrieved from woodrow.org

Morris, Richard; Last Sorcerers: Path from Alchemy to the Periodic Table; Joseph Henry Press; 2003

Robert Whilhelm Bunsen NNDB profile

Robert Bunsen Wikipedia Entry






Monday, March 25, 2013

Sidney W. Fox

Sidney Walter Fox was born on March 24, 1912 in Los Angeles, California. His father, Jacob Fox, was a wigmaker and his mother, Louise Berman, was a Ukrainian immigrant. He attended the University of California Los Angeles, earning a bachelors in chemistry and the California Institute of Technology, earning a PhD in 1940. He taught briefly at the University of California Berkeley and the University of Michigan before moving to Iowa State University in 1943 and where he was a professor of biochemistry from 1947 to 1954. He was professor of chemistry at Florida State University from 1954 to 1964 when he became director of the Institute of Molecular and Cellular Evolution at the University of Miami. He retired in 1989.

Fox's biochemical research dealt with the study of the origin of life. Fox's research showed that amino acids, when subjected to heat, will spontaneously form polypeptide compounds, Fox dubbed proteinoids (the earlier Miller-Urey experiment had shown that amino acids could have been generated by conditions of the Earth's primordial atmosphere). Fox hypothesized that these poly-amino acid molecules could be the origin the protein molecules that make up living things.  When put into water or salt solution these proteinoids form microspheres, that are one or two microns in diameter. These microspheres behave like cellular membranes, budding off and forming new microspheres. Fox believed that these proteinoid microspheres were the origin of bacterial cell walls. Fox's proteinoid theory for the origin of life has its detractors, who believe that concentrations of the particular amino acids that Fox used in his experiments could not have been present in the primordial environment. Fox was one of the first scientists to examine moon rocks brought back to Earth by NASA.

Fox died on August 10, 1998 in Mobile, Alabama.


References:

Daintith, John; "Fox, Sydney Walter" in Biographical Encyclopedia of Scientists, Third Edition; CRC Press; 2010

"Sydney W Fox, Analyzed First Moon Rocks"; Los Angeles Times; August 18, 1998

Sydney W. Fox Wikipedia Entry

Sunday, March 17, 2013

Walter Hess

Walter Rudolf Hess was born on March 17, 1881 in Frauenfeld in the Swiss canton of Thurgau. He was the second of three children on Clemens and Gertrude Hess. His father was a physics teacher in a grammar school and ran a weather station. Hess learned physics from his father and helped the family electrify the family's apartment. He began studying medicine in Lausanne in 1899, finishing his studies in Berlin, Kiel, and Zurich. After passing his qualifying medical exam in Zurich, in 1906, he served as a surgeon's assistant. While a surgeon's assistant he developed a device to measure blood viscosity that was widely used clinically but has been replaced by the measurement of blood sedimentation rate. He was later an ophthalmologists's assistant and then an ophthalmologist. Hess's interest was in physiology and in 1912 he gave up a prosperous practice to take the position of a physiologist's assistant, working under Justus Gaule. In 1916, with Gaule's retirement, Hess first became interim director and then director and professor of the Department of Physiological Institute at the University of Zurich. He remained there until his retirement in 1951.

Hess's physiological studies included the circulatory system, but he is most remembered for his research into brain function. Using a fine tipped electrode he was able to stimulate regions of the mid-brain and develop a map of its functions. Mammalian brains are largely divided three regions: the hindbrain, the midbrain, and the forebrain, moving up from the spinal cord to the head (for a diagram of the brain showing some of the functions of different regions see here). Different regions of the brain have different functions with the hind brain, or brain stem, having body maintenance functions including body temperature, heart and breathing control. The forebrain includes the four lobes of the cerebellum which control thought, memory, and movement. Hess, using his electrode to stimulate regions of the hypothalamus, a region of the mid brain, found that he could stimulate excitement or apathy. He also found regions where he could stimulate hunger and thirst. For his researches he was awarded the 1949 Nobel Prize in medicine and physiology "for his discovery of the functional organization of the interbrain as a coordinator of the activities of the internal organs."

Other honors won by Hess include the Marcel Benoist Prize in 1932 and honorary doctorates from the Universities of Bern, Geneva, and Freiburg and from McGill University.

He died on August 12, 1973.


References:

Hess, C.W.; "Walter Hess (17.3.1881-12.6.1973)"; Schwiezer Archiv fur Neurologie und Psychiatrie (2008)159:259-261

Walter Hess Nobel Biography

Walter Hess Wikipedia Entry

Sunday, March 10, 2013

Jeremias B. Richter

Jeremias Benjamin Richter was born on March 10, 1762 in Hirschberg, in Silesia, then part of Prussia, but now part of Poland. He became a mining official in Breslau in 1794 and in 1800 was appointed assessor of the Department of Mines and chemist to the royal porcelain factory in Berlin. He died in Berlin on April 4, 1807.

Richter is most remembered for deducing the law of equivalent proportions. The law of equivalent proportions states that when two or more elements are combined, the weights of these elements are proportional to their equivalent weights, so as such the two are related. This concept, that elements combine in definite ratios to form compounds, is the basis of stoichiometry, a word coined by Richter to describe, "the art of chemical measurements, which has to deal with the laws according to which substances unite to form chemical compounds". This discovery hinted at the existence of atoms, which today we know combine in definite ratios to form compounds.

At the time Richter's work was largely ignored due to his obscure and clumsy writing style and his emphasis on mathematics, which chemists at the time were not interested in. His discoveries were wrongly ascribed to Carl Wenzel and it was not until 1841 when Henri Hess gave Richter proper credit.


References:

Leicester, Henry Marshall and Klickstein, Herbert S.; "Jeremias Benjamin Richter: 1762-1807"; found in A Source Book in Chemistry, 1400-1900; Harvard University Press; 1969

"Richter, Jeremias Benjamin"; Encyclopedia Britannica; 1911

Jeremias Benjamin Richter Wikipedia Entry

Monday, February 25, 2013

Heinrich Lenz

Heinrich Friedrich Emil Lenz was born on February 12, 1804 in Dorpat in the Russian Empire, which is now Tartu, Estonia. He studied theology at the University of Dorpat from 1820 to 1823, but switched to physics. After graduation he served as a scientist with navigator Otto von Kotzebue's third circumnavigation of the world, from 1923 to 1926, where he studied climate and took salinity and specific gravity measurements of sea water. He published several papers based on this trip, and in 1832 published his first paper on electromagnetism. From 1840 to 1863 he was dean of physics at the University of St. Petersburg and he served as rector there from 1863 until his death.

Lenz is most remembered for his studies of electromagnetism. At the beginning of the nineteenth century scientists were beginning to understand electricity and magnetism, but did not understand the relationships between the two. Lenz took one of the first steps in filling in that gap by formulating Lenz's Law. Repeating the work of James Faraday, Lenz observed that when a electrical current is generated by a changing magnetic field, the magnetic field generated by that electrical current opposes the magnetic field that generated the current (see here for a graphic demonstration of this). This result is due to the law of conservation of energy. Lenz's results were copiously documented so that they could be easily repeated and his quantitative results were more thorough than the qualitative work that had been done previous to him.

In addition to Lenz's Law, Lenz also independently discovered Joule's Law and worked on developing electroplating. Lenz is honored by the use of the letter L to represent capacitance in physics equations.

Lenz died on February 10, 1865, in Rome, after suffering a stroke.


References:

Tooker, J.B.; "A Discussion of the Life of Heinrich Friedrich Emil Lenz"; Retrieved from: jtooker.com

National High Magnetic Field Laboratory; "Heinrich Friedrich Emil Lenz (1804-1865)" Retrieved from: magnet.fsu.edu

Heinrich Lenz Wikipedia Entry

Monday, February 18, 2013

Tobias Mayer

Tobias Mayer was born on February 17, 1723 in Marbach a small town on the Neckar river a few miles from Stuttgart. His father was a cart-wright and an engineer who made water systems. When Mayer was young he plagued his mother with requests for paper and writing supplies to copy his father's water system plans. Mayer was orphaned when he was 8 and after a time in an orphanage he was taken on by a shoemaker named Gottlieb Kandler, from whom he learned geometry and architecture. Mayer attended the Latin school in Esslingen where he studied mathematics on his own and reached the top class in two years. He published a book on geometry when he was 18. He attempted to become a artillery officer but circumstances prevented him realizing this goal. He became an excellent map maker and in 1746 he joined the Homann Cartographic Bureau in Nuremberg. In 1751 he was appointed professor of mathematics and economy at the Georg August Academy in Gottingen.

Mayer is mostly remembered for his astronomical observations of the moon. In 1748 and 1749 he made a map of the lunar surface and came to the conclusion that there was no atmosphere on the moon. At the time this was a controversial opinion. His lunar tables, published in 1752, were recommended by the British Astronomer Royal, for their utility in determining longitude while at sea. Mayer's widow received a 3000 pound grant from the British government after bringing them to England.

A crater on the moon is named is named after him. He is often confused with his son, Johann Tobias Mayer, who was a physicist.

Mayer died during the French occupation of Gottingen on February 20, 1762.


References:

Forbes, Eric Gray; "The Life and Work of Tobias Mayer (1723-62)"; Quarterly of the Royal Astronomical Society (1969)8:227-251

Wepster, Steven; "Father and Son Mayer"; Retrieved from staff.science.uu.nl

Tobias Mayer Wikipedia Entry