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Zernike, Frits

(Encyclopedia)Zernike, Frits, 1888–1966, Dutch physicist, Ph.D. Univ. of Amsterdam, 1915. He was on the faculty at the Univ. of Groningen from 1915 until his retirement in 1958. Zernike received the 1953 Nobel Pr...

farsightedness

(Encyclopedia)farsightedness or hyperopia, condition in which far objects can be seen easily but there is difficulty in near vision. It is caused by a defect of refraction in which the image is focused behind the r...

night blindness

(Encyclopedia)night blindness, inability to see normally in subdued light. It is usually a result of vitamin A deficiency. The rod cells, one of two light-sensitive areas of the retina of the eye, are impaired in t...

pilocarpine

(Encyclopedia)pilocarpine pīlōkärˈpēn [key], naturally occurring alkaloid obtained from plants of the genus Pilocarpus (family Rutaceae). By mimicking the effects of acetylcholine, pilocarpine acts as a stimul...

Purkinje, Johannes Evangelista

(Encyclopedia)Purkinje, Johannes Evangelista yōhänˈəs āˌväng-gālĭsˈtä po͝orˈkĭnyā [key], 1787–1869, Czech physiologist. While professor (1823–50) at the Univ. of Breslau he pioneered in establish...

Wald, George

(Encyclopedia)Wald, George, 1906–97, American biochemist, b. New York City, Ph.D. Columbia, 1932. He spent most of his career on the faculty at Harvard. In 1967 Wald, Haldan K. Hartline, and Ragnar Granit receive...

Granit, Ragnar

(Encyclopedia)Granit, Ragnar, 1900–1991, Swedish physiologist, M.D., Univ. of Helsinki, 1927. A professor at the Univ. of Helsinki from 1927, he joined the faculty of the Karolinska Institute, Sweden, in 1940. Gr...

glaucoma

(Encyclopedia)glaucoma glôkōˈmə [key], ocular disorder characterized by pressure within the eyeball caused by an excessive amount of aqueous humor (the fluid substance filling the eyeball). This causes pressure...