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