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Apex beat. The apex beat (lat. ictus cordis ), also called the apical impulse, [1] is the pulse felt at the point of maximum impulse ( PMI ), which is the point on the precordium farthest outwards (laterally) and downwards (inferiorly) from the sternum at which the cardiac impulse can be felt. The cardiac impulse is the vibration resulting from ...
Overview. Your pulse is the vibration of blood as your heart pumps it through your arteries. You can feel your pulse by placing your fingers over a large artery that lies close to your skin. The ...
t. e. In mathematical analysis, the Dirac delta function (or δ distribution ), also known as the unit impulse, [1] is a generalized function on the real numbers, whose value is zero everywhere except at zero, and whose integral over the entire real line is equal to one. [2] [3] [4] Since there is no function having this property, modelling the ...
All-or-none law. In physiology, the all-or-none law (sometimes the all-or-none principle or all-or-nothing law) is the principle that if a single nerve fibre is stimulated, it will always give a maximal response and produce an electrical impulse of a single amplitude. If the intensity or duration of the stimulus is increased, the height of the ...
As an action potential (nerve impulse) travels down an axon there is a change in electric polarity across the membrane of the axon. In response to a signal from another neuron, sodium- (Na +) and potassium- (K + )–gated ion channels open and close as the membrane reaches its threshold potential. Na + channels open at the beginning of the ...
In neuroscience, threshold potentials are necessary to regulate and propagate signaling in both the central nervous system (CNS) and the peripheral nervous system (PNS). Most often, the threshold potential is a membrane potential value between –50 and –55 mV, [1] but can vary based upon several factors. A neuron 's resting membrane ...
The impulse response, considered as a Green's function, can be thought of as an "influence function": how a point of input influences output. Practical applications. In practical systems, it is not possible to produce a perfect impulse to serve as input for testing; therefore, a brief pulse is sometimes used as an approximation of an impulse.
v. t. e. In classical mechanics, impulse (symbolized by J or Imp) is the change in momentum of an object. If the initial momentum of an object is p1, and a subsequent momentum is p2, the object has received an impulse J : Momentum is a vector quantity, so impulse is also a vector quantity. Newton’s second law of motion states that the rate of ...