| group velocity | <radiobiology> This is derived from the dispersion relation as Vgroup = dw/dk, the group velocity is the rate at which modulations or information within a wave travel through a given medium. (09 Oct 1997) |
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| critical velocity | <biology> The maximum speed a device or organism can sustain over a specified distance or length of time, or the maximum velocity against which device or organism can sustain a position over a specified length of time. <marine biology> Velocity through which a fish will not swim, creating a velocity barrier. (09 Oct 1997) |
| sedimentation velocity | The rate of movement of a substance, typically a macromolecule, in centrifugation; these centrifugation studies provide data on the structure of the macromolecule. (05 Mar 2000) |
| steady-state velocity | The velocity of an enzyme-catalyzed reaction in which, over the time course of the study, the concentration of any enzyme species is constant (i.e., for an enzyme-substrate binary complex, ES, d[ES]/dt&apprxeq;00; for this to hold true, the total enzyme concentration must be much less than the initial substrate concentration. Synonym: steady-state rate. (05 Mar 2000) |
| drift velocity | <radiobiology> Characteristic velocity at which the centre of a particle's orbit (guiding centre) drifts when drift motion (see above) occurs. (09 Oct 1997) |
| initial velocity | The rate of a reaction, e.g., an enzyme-catalyzed reaction, at the early stages of the reaction such that the product(s) concentrations have not risen to a level to significantly affect the observable rate; typically, initial velocities are observed when less than 10% of the reaction's approach toward equilibrium has occurred. Synonym: initial rate. (05 Mar 2000) |
| thermal velocity | <radiobiology> Average speed (magnitude of velocity) of a particle at a given temperature (in a Maxwellian velocity distribution). (09 Oct 1997) |
| electron velocity | <physics> The rate of motion of an electron. (05 Aug 1998) |
| fish velocity | The velocity at the location occupied by a fish, measured at the fish's snout. (09 Oct 1997) |
| force-velocity curve | The relationship between isotonic velocity of shortening and afterload for a contracting muscle. (05 Mar 2000) |
| aberrant ventricular conduction | Abnormal intraventricular conduction of a supraventricular beat, especially where surrounding beats are normally conducted. Synonym: ventricular aberration. (05 Mar 2000) |
| accelerated conduction | Any pathologically increased speed of conduction; usually occurs between the atrium and ventricles as in the Wolff-Parkinson-White and Lown-Ganong-Levine syndromes; such accelerated pathways provide the bases for particular forms of reentry tachycardia. (05 Mar 2000) |
| A-H conduction time | Forward conduction of the cardiac impulse from atria to ventricles via the A-V node or any bypass tract, represented in the electrocardiogram by the P-R interval. P-H conduction time is from the onset of the P wave to the first high frequency component of the His bundle electrogram (normally 119 ± 38 msec); A-H conduction time is from the onset of the first high frequency component of the atrial electrogram to the first high frequency component of the His bundle electrogram (normally 92 ± 38 msec); P-A conduction time is from the onset of the P wave to the onset of the atrial electrogram (normally 27 ± 18 msec). (05 Mar 2000) |
| air conduction | In relation to hearing, the transmission of sound to the inner ear through the external auditory canal and the structures of the middle ear. (05 Mar 2000) |
| anomalous conduction | Conduction of cardiac electrical impulses through any abnormal pathway. (05 Mar 2000) |