Kenneth Stewart Cole

Infobox Person
name = Kenneth Stewart Cole


image_size = 250px
caption =
birth_date = July 10, 1900
birth_place = Ithaca, New York
death_date = April 18, 1984
death_place = La Jolla
occupation = Scientist
spouse = Elizabeth Evans Roberts
parents = Charles Nelson Cole
Mabel Stewart (c1900-1966)
children = Roger Braley Cole

Kenneth Stewart Cole (July 10, 1900 – April 18, 1984) was an American biophysicist described by his peers as "a pioneer in the application of physical science to biology". [Goldman, D.E. 1985. Kenneth S. Cole 1900-1984. "Biophysical Journal" 47:859-860] Cole was awarded the National Medal of Science in 1967. cite news |first= |last= |authorlink= |coauthors= |title=Kenneth Cole, 83, Scientist, is Dead |url= |quote= Kenneth S. Cole, winner of the National Medal of Science and a pioneer in the study of the electrical properties of nerves and other living cells, died Wednesday at the Wesley Palms Retirement Home in La Jolla, California He was 83 years old. Dr. Cole, known as the "father of biophysics," was one of the first scientists to apply the concepts and techniques of physics to the study of the excitation and response of living cells. His studies of electrical resistance in nerve cells, especially those of squid, laid the foundation for the rapid advance of neurophysiology in the 1930's and 1940's. |publisher=New York Times |date=April 20, 1984 |accessdate=2007-06-14 ] [Schwan HP. 2001. The concept of bioimpedance from the start: evolution and personal historical reminiscences. Proc. IX Bioimpedance Conf., Oslo, Norway]

Biography

Kenneth Cole was known to his wife as Ken but to all his friends as Kacy. His father, Charles Nelson Cole, was an instructor in Latin at Cornell University, and two years later the family moved to Oberlin, Ohio, when his father took a post at Oberlin College. His father would later become the Dean. Kenneth's mother was Mabel Stewart, and he had a younger brother, Robert, with whom he remained very close throughout his life despite a large difference in age; they were joint authors of four papers published between 1936 and 1942.

Cole graduated from Oberlin College in 1922 and received a Ph.D. in physics with F. K. Richtmyer from Cornell University in 1926. He spent summers working at the General Electric Laboratory in Schenectady, New York.

In 1932, Cole married Elizabeth Evans Roberts, an attorney. Later, her work was mostly concerned with civil rights and in 1956 she joined the staff of the new Civil Rights Commission cite web |first=Andrew |last=Huxley |url=http://www.nap.edu/readingroom/books/biomems/kcole.html |title=Kenneth Stewart Cole |accessdate=2007-06-14 |authorlink=Andrew Huxley |work= ]

Kenneth joined the staff of Columbia University in 1937 and remained there until 1946. He had also been associated with the Presbyterian Hospital, and the Guggenheim Foundation for Advanced Study at Princeton University and the University of Chicago. From 1949 to 1954 he was the technical director of the Naval Medicine Research Institute in Bethesda, Maryland. In 1954 he became chief of the laboratory of biophysics of the National Institute of Neurological Diseases and Blindness. He achieved advances that led to the "sodium theory" of nerve transmission that later won Nobel Prizes for Alan L. Hodgkin and Andrew F. Huxley in 1947. He was awarded the National Medal of Science in 1967, the award citation, read: "As a result, we know far more about how the nervous system functions." In 1972 he was made a member of the Royal Society of London. The United States Biophysical Society awards the Kenneth S. Cole medal to a scientist studying cell membranes. In 1980 he became an adjunct professor of the Department of Neurosciences at the Scripps Institute of Oceanography in San Diego. He had a son, Roger Braley Cole, and a daughter, Sally Cole. He died on April 18, 1984.

Electrical Model of Tissue

Tissue can be modeled as an electrical circuit with resistive and capacitive properties:

Its dispersion and absorption are represented by the empirical formula:

$epsilon^*\; -\; epsilon\_infty\; =\; dfrac\{epsilon\_0\; -\; epsilon\_infty\}\{1\; +\; (iomega\; au\_0)^\{1-alpha$

In this equation $epsilon^*$ is the complex dielectric constant, $\{epsilon\_0\; \}$ and $epsilon\_infty$ are the "static" and "infinite frequency" dielectric constants, $omega\; =\; 2pi$ times the frequency, and $au\_0$ is a generalized relaxation time. The parameter $alpha$ can assume values between 0 and 1, the former value giving the result of Debye for polar dielectrics. This expression requires that the locus of the dielectric constant in the complex plane be a circular arc with end points on the axis of reals and center below the axis.

References

Publications

*Cole, K.S. 1979. Mostly membranes. "Annual Review of Physiology" 41:1-23 PMID: 373584
*Cole, K. S., and R. H. Cole. 1941. Dispersion and absorption in dielectrics. J. Chem. Phys. 9:341-351 [http://link.aip.org/link/?JCPSA6/9/341/1]