Sunday, April 13, 2014
Cosmic rays are charged atomic particles that bombard the Earth originating from the supernovas of large stars and in smaller amounts from active galactic centers. The surface of the Earth is protected from these charged particles by the Earth's atmosphere and magnetic field, although some reach the Earth's surface. Life on Earth would not survive were it not for this protection. Initially these particles were believed to be a form of electromagnetic radiation, but in 1927 Jacob Clay measured the amount of rays detected as he voyaged from Netherlands to Java and reported that the amount of rays hitting the Earth's surface changed with latitude with a minimum at the equator. This demonstrated that the "rays" were not photons and must be charged particles that were deflected by the Earth's magnetic field.
In 1932 Rossi became a professor of experimental physics at the University of Padua. In 1938 he was dismissed from his professorship because he was Jewish. After a brief stays at the Bohr Institute in Copenhagen and University of Manchester, Rossi emigrated to the United States where he took a position at Cornell University in 1940. In 1943 Rossie joined the Manhattan Project in Los Alamos, New Mexico where he was co-chair, with Hans Straub, of the "detector group", which was responsible for designing detectors used by the scientists developing the atomic bomb.
In 1946 Rossi took a professorship at the Massachusetts Institute of Technology at the new Laboratory of Nuclear Science. At MIT Rossi focused on studying newly discovered subatomic particles. Rossi focused on developing detectors that could be launched into space to study cosmic rays that are not affected by the Earth's atmosphere and magnetic field. Rossi retired in 1970, but continued teaching. Awards won by Rossi include the Rumford Prize from the American Academy of Arts and Sciences (1976), the Elliot Cresson Medal from the Franklin Institute (1974) and the National Medal of Science (1985). Rossi was also awarded honorary doctorates from the Universities of Palermo, Durham, and Chicago.
Rossi died on November 21, 1993, suffering a cardiac arrest.
Clark, George W.; "Bruno Benedetto Rossi: 1905-1993"; in Biographical Memoirs Vol. 75 (1997) National Academy Press
Clark, George W.; "The Contributions of Bruno B. Rossi to Particle Physics and Astrophysics"; Retrieved from: http://www.brera.unimi.it
Bruno Rossi Wikipedia Entry
Sunday, April 6, 2014
Lynen's research dealt with determining the biochemical pathways by which cells produce fatty acids and sterols. Working with Konrad Bloch, he discovered the pathway by which cholesterol is synthesized. Later he determined the structure of acytel-coenzyme A. Acetyl-CoA is an important biochemical intermediate. It feeds two carbon acetic acid fragments from glycolysis (the initial steps by which cells break down glucose) into the citric acid cycle to generate cellular energy. It also is the basis of fatty acid and cholesterol synthesis using the two carbon acetate to build longer carbon chains to store energy or produce bigger carbon molecules. For their work Lynen and Bloch were awarded the Nobel Prize in Physiology and Medicine in 1964.
Other awards won by Lynen include the Grand Cross of Merit with Star and Sash of the Federal Republic of Germany in 1965, Norman Medal of the German Society for Fat Research in 1967, the Pour le mérite für Wissenschaften und Künste in 1971, and the Austrian Decoration for Science and Art in 1972.
Lynen died on August 6, 1979.
Kresge, Nichole, Simoni, Robert D., and Hill, Robert L.; "Biotin Dependent Enzymes: the Work of Feodor Lynen"; Journal of Biological Chemistry (2009)284:e6-e7
Feodor Lynen Nobel Biography
Feodor Lynen Wikipedia Entry