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neuralgia

(Encyclopedia)neuralgia no͝orălˈjə, nyo͝o– [key], acute paroxysmal pain along a peripheral sensory nerve. Unlike neuritis, there is no inflammation or degeneration of nerve tissue. Neuralgia occurs commonly ...

neutrality

(Encyclopedia)neutrality, in international law, status of a nation that refrains from participation in a war between other states and maintains an impartial attitude toward the belligerents. Neutrality is not to be...

Newcastle disease

(Encyclopedia)Newcastle disease, pneumoencephalitis, acute viral disease of domestic poultry. Newcastle disease is characterized by sneezing, coughing, and nervous behavior. Affected birds may show tremors, circlin...

Nibelungen

(Encyclopedia)Nibelungen –lētˌ [key] [song of the Nibelungen] is a long Middle High German epic by a south German poet of the early 13th cent. It includes pagan legends and traditions but is patently the produc...

nihilism

(Encyclopedia)nihilism nīˈəlĭzəm [key], theory of revolution popular among Russian extremists until the fall of the czarist government (1917); the theory was given its name by Ivan Turgenev in his novel Father...

automation

(Encyclopedia)automation, automatic operation and control of machinery or processes by devices, such as robots that can make and execute decisions without human intervention. The principal feature of such devices i...

Nipah virus

(Encyclopedia)Nipah virus, RNA virus of the genus Henipavirus, family Paramyxoviridae, that rarely infects humans but can cause deadly encephalitis. In humans, the virus typically incubates for 4 to 14 days before ...

nonlinear dynamics

(Encyclopedia)nonlinear dynamics, study of systems governed by equations in which a small change in one variable can induce a large systematic change; the discipline is more popularly known as chaos (see chaos theo...

norovirus

(Encyclopedia)norovirus or Norwalk virus, highly contagious viral disease caused by infection with an RNA virus of the genus Norovirus. The virus causes acute gastroenteritis, usually one to two days after infectio...

nullification

(Encyclopedia)nullification, in U.S. history, a doctrine expounded by the advocates of extreme states' rights. It held that states have the right to declare null and void any federal law that they deem unconstituti...