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electrochemistry

(Encyclopedia)electrochemistry, science dealing with the relationship between electricity and chemical changes. Of principal interest are the reactions that take place between electrodes and the electrolytes in ele...

hearing aid

(Encyclopedia)hearing aid, device used in some forms of deafness to amplify sound before it reaches the auditory organs. Modern hearing aids are electronic. They contain a tiny receiver and a transistor amplifier, ...

Südhof, Thomas Christian

(Encyclopedia)Südhof, Thomas Christian, 1955–, German-American biochemist. M.D., b. Göttingen, Germany, Ph.D. Georgia Augusta Univ., Göttingen, 1982. Südhof joined the faculty at the Univ. of Texas Southweste...

sphagnum

(Encyclopedia)sphagnum sfăgˈnəm [key] or peat moss, any species of the large and widely distributed genus Sphagnum, economically the most valuable moss. Sphagnums, the principal constituent of peat, typically gr...

spinal puncture

(Encyclopedia)spinal puncture, surgical penetration of the spinal canal by a hollow needle introduced between two of the lumbar vertebrae. The arrangement permits injection of antibiotics or anesthetics (see anesth...

Winter, Sir Gregory Paul

(Encyclopedia)Winter, Sir Gregory Paul, 1951–, British biochemist, Ph.D. Cambridge, 1976. He has spent most of his career as a researcher at the Laboratory of Molecular Biology in Cambridge, England, where since ...

endocrine system

(Encyclopedia)endocrine system ĕnˈdəkrĭn [key], body control system composed of a group of glands that maintain a stable internal environment by producing chemical regulatory substances called hormones. The end...

lymphatic system

(Encyclopedia)CE5 Lymphatic system lymphatic system lĭmfătˈĭk [key], network of vessels carrying lymph, or tissue-cleansing fluid, from the tissues into the veins of the circulatory system. The lymphatic sy...

quasicrystal

(Encyclopedia)quasicrystal kwāˈzīkrĭsˌtəl, kwäzˈē– [key] or quasiperiodic solid, solid body that exhibits such crystalline features as symmetry and repeating patterns of unit cells (regular arrangements ...

radiation sickness

(Encyclopedia)radiation sickness, harmful effect produced on body tissues by exposure to radioactive substances. The biological action of radiation is not fully understood, but it is believed that a disturbance in ...