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starvation

(Encyclopedia)starvation, condition in which deprivation of food has forced the body to feed on itself. Causes are famine, fasting, malnutrition, or abnormalities of the mucosal lining of the digestive system. Fami...

skeleton, in winter sports

(Encyclopedia)skeleton, in winter sports, a type of small, very low, steel-frame sled on which one person, lying face down, slides headfirst down snowy hillsides or down steeply banked, curving, iced chutes similar...

pelvis

(Encyclopedia)pelvis, bony, basin-shaped structure that supports the organs of the lower abdomen. It receives the weight of the upper body and distributes it to the legs; it also forms the base for numerous muscle ...

phlogiston theory

(Encyclopedia)phlogiston theory flōjĭsˈtŏn [key], hypothesis regarding combustion. The theory, advanced by J. J. Becher late in the 17th cent. and extended and popularized by G. E. Stahl, postulates that in all...

chemical equation

(Encyclopedia)chemical equation, group of symbols representing a chemical reaction. There are a number of other symbols used in chemical equations. A symbol written above or below the reaction arrow indicates spe...

Rankine temperature scale

(Encyclopedia)Rankine temperature scale, temperature scale having an absolute zero, below which temperatures do not exist, and using a degree of the same size as that used by the Fahrenheit temperature scale. Absol...

van der Waals, Johannes Diderik

(Encyclopedia)van der Waals, Johannes Diderik yōhäˈnəs dēˈdərĭk vän dər väls [key], 1837–1923, Dutch physicist. It had been known for some time that the behavior of real gases differs from that of an i...

Franklin, Rosalind Elsie

(Encyclopedia)Franklin, Rosalind Elsie, 1920–58, English molecular biologist and chemist, grad. Newnham College, Cambridge (1941). She spent most of the war years (1942–45) working for the British Coal Utilisat...

Hershey, Alfred Day

(Encyclopedia)Hershey, Alfred Day, 1908–1997, American microbiologist, b. Owosso, Mich., Ph.D., Michigan State College (now Michigan State Univ.), 1934. Hershey was a professor at the Washington Univ. School of M...

allotropy

(Encyclopedia)allotropy əlŏˈtrəpē [key] [Gr.,=other form]. A chemical element is said to exhibit allotropy when it occurs in two or more forms in the same physical state; the forms are called allotropes. Allot...