| sedimentation coefficient | <physics> The ratio of the velocity of sedimentation of a molecule to the centrifugal force required to produce this sedimentation. It is a constant for a particular species of molecule and the value is given in Svedberg units that, it should be noted, are nonadditive. (18 Nov 1997) |
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| blood sedimentation | Measurement of rate of settling of erythrocytes in anticoagulated blood. (12 Dec 1998) |
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| rate, erythrocyte sedimentation | A sedimentation rate, or sed rate , is a blood test that detects and is used to monitor inflammation activity. It is measured by recording the rate at which red blood cells (rbcs) sediment in a tube over time. It increases (the rbcs sediment faster) with more inflammation. (12 Dec 1998) |
| rate, sedimentation | A sedimentation rate, or sed rate , is a blood test that detects and is used to monitor inflammation activity. It is measured by recording the rate at which red blood cells (rbcs) sediment in a tube over time. It increases (the rbcs sediment faster) with more inflammation. (12 Dec 1998) |
| sedimentation | <procedure> The act of causing the deposit of sediment, especially by the use of a centrifugal machine. (18 Nov 1997) |
| sedimentation constant | The constant s in Svedberg's equation for estimating the molecular weight of a protein from the rate of movement in a centrifugal field:where M is the molecular weight, R the gas constant, T the absolute temperature, D the diffusion constant (in square centimeters per second), V the partial specific volume of the protein, ρ the density of the solvent. The constant s, with dimensions of time per unit of field force (s = drb/dt /ω2ro where rb is the position at time t, r0 is the position at time 0, and ω is the angular velocity) is usually between 1 × 10-13 and 200 × 10-13 second. The Svedberg unit (S) is arbitrarily set at 1 × 10-13 second and is very often used to describe the sedimentation rate of macromolecules; e.g., 4 S RNA. Synonym: sedimentation coefficient. (05 Mar 2000) |
| sedimentation rate | A sedimentation rate, or sed rate , is a blood test that detects and monitors inflammation activity. It is measured by recording the rate at which red blood cells (rbcs) sediment in a tube over time. It increases (the rbcs sediment faster) with more inflammation. (12 Dec 1998) |
| 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) |
| erythrocyte sedimentation rate | <investigation> A test that measures the rate at which red blood cells settle through a column of liquid. A non-specific index of inflammation. Acronym: ESR (11 Nov 1997) |
| zeta sedimentation ratio | The ratio of the zetacrit to the haematocrit, normally 0.41 to 0.54 (41 to 54%); it is a sensitive indicator of the erythrocyte sedimentation rate (ESR) and, unlike the latter, is unaffected by anaemia, which tends to elevate the ESR. (05 Mar 2000) |
| absorption coefficient | <physics> Measures the degree of wave absorption defined as the fraction of wave energy lost as the wave travels a unit distance. See: absorption. (15 Jan 1998) |
| activity coefficient | <chemistry> The factor by which the value of a concentration of a solute must be multiplied to determine its true thermodynamic activity. (06 May 1997) |
| attenuation coefficient | 1. <radiobiology> Compton: The fractional number of photons removed from a beam of radiation per unit thickness of material through which it is passing as a result of Compton effect interactions. 2. Linear: The fractional number of photons removed from a beam of radiation per unit thickness of material through which it is passing due to all absorption and scattering processes. 3. Pair Production: That fractional decrease in the intensity of a beam of ionising radiation due to pair production in a medium through which it passes. 4. Photoelectric Effect: That fractional decrease in the intensity of a beam of ionising radiation due to photoelectric effect in a medium through which it passes. (16 Dec 1997) |
| biological coefficient | Rarely used term denoting the energy expended by the body at rest. (05 Mar 2000) |
| Bunsen's solubility coefficient | The milliliters of gas STPD dissolved per milliliter of liquid and per atmosphere (760 mm Hg) partial pressure of the gas at any given temperature. (05 Mar 2000) |
| velocity coefficient | The rate of transformation of a unit mass of substance in a chemical reaction. (05 Mar 2000) |