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cirrhosis

(Encyclopedia)cirrhosis sərōˈsəs [key], degeneration of tissue in an organ resulting in fibrosis, with nodule and scar formation. The term is most often used in relation to the liver, because that organ is most...

Le Châtelier's principle

(Encyclopedia)Le Châtelier's principle, chemical principle that states that if a system in equilibrium is disturbed by changes in determining factors, such as temperature, pressure, and concentration of components...

pump

(Encyclopedia)pump, device to lift, transfer, or increase the pressure of a fluid (gas or liquid) or to create a vacuum in an enclosed space by the removal of a gas (see vacuum pumps under vacuum). The centrifugal ...

terrace

(Encyclopedia)terrace, a level field built on top of a hillslope into the floor of a deep valley to improve cultivation of crops. Terracing uses the runoff from the hill to increase soil retentiveness and arability...

cocaine

(Encyclopedia)cocaine kōkānˈ, kōˈkān [key], alkaloid drug derived from the leaves of the coca shrub. A commonly abused illegal drug, cocaine has limited medical uses, most often in surgical applications that ...

Ashkin, Arthur

(Encyclopedia)Ashkin, Arthur, 1922–2020, American physicist, b. Brooklyn, N.Y., Ph.D. Cornell, 1952. Ashkin worked for four decades at Bell Laboratories, retiring in 1992. Ashkin researched microwaves, nonlinear ...

composition board

(Encyclopedia)composition board, wood product produced in the form of a board or sheet, formed of cellulose fibers or particles derived from wood or other sources, and used principally as a building material. The o...

bladder, urinary

(Encyclopedia)bladder, urinary, muscular sac located in the pelvis that stores urine and contracts to expel it from the body. Urine enters the bladder from the kidneys through the ureters and is discharged from the...

welding

(Encyclopedia)welding, process for joining separate pieces of metal in a continuous metallic bond. Cold-pressure welding is accomplished by the application of high pressure at room temperature; forge welding (forgi...

Murphy, William Parry

(Encyclopedia)Murphy, William Parry, 1892–1987, American physician, b. Stoughton, Wis., M.D. Harvard, 1920. He taught at Harvard from 1923 and was associated with the Peter Bent Brigham Hospital, in Boston, from ...