| velocity space instability | <radiobiology> A class of instabilities driven by particle distributions (in velocity space) which are not in thermal equilibrium. (09 Oct 1997) |
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| maximum velocity | The maximum rate of an enzyme-catalyzed reaction that can be achieved by progressively increasing the substrate concentration at a given enzyme concentration; in cases of substrate inhibition, Vmax is an extrapolated value in the absence of such inhibition; Cf.: Michaelis-Menten equation. The maximum initial rate of shortening of a myocardial fibre that can be obtained under zero load; used to evaluate the contractility of the fibre. (05 Mar 2000) |
| 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) |
| 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) |
| nerve conduction velocity | The rate of impulse conduction in a peripheral nerve or its various component fibres, generally expressed in meters per second. (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) |
| 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) |