| thermal sensors | Sensors that detect tiny changes in heat or temperature. (14 Nov 1997) |
|---|---|
| thermal spectrum | The part of the invisible spectrum of wave length just longer than that of visible red light. Synonym: thermal spectrum. (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) |
| automated differential leukocyte counter | An instrument using digital imaging or cytochemical techniques to differentiate leukocytes. (05 Mar 2000) |
| Begg light wire differential force technique | An orthodontic appliance utilizing small gauge labial wires with expansion and contraction loops formed into it and attached to bands fitted to individual teeth; sometimes called Begg light wire differential force technique. (05 Mar 2000) |
| calorimetry, differential scanning | Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample. (12 Dec 1998) |
| white blood cell differential | <haematology> The white blood cell differential is a percentage of each type of white blood cell based on a count of 100 white cells. A change in the white blood cell type (to neutrophils or bands) can indicate a bacterial infection. Neutrophils, bands, lymphocytes, monocytes, basophils and eosinophils are all included. (13 Nov 1997) |
| semantic differential | Analysis of word concepts by the association of polar adjectives, e.g., good-bad, with the concept, father. The adjectives are usually scaled in 7 steps. The subject's placement of the concept on the adjectival scale indicates the connotative meaning of the concept. (12 Dec 1998) |
| diagnosis, differential | The determination of which two or more diseases with similar symptoms is the one from which a patient is suffering from based on an analysis of the clinical data. (27 Sep 1997) |
| differential | 1. Relating to or indicating a difference; creating a difference; discriminating; special; as, differential characteristics; differential duties; a differential rate. "For whom he produced differential favors." (Motley) 2. <mathematics> Of or pertaining to a differential, or to differentials. 3. <mechanics> Relating to differences of motion or leverage; producing effects by such differences; said of mechanism. Differential calculus. <mathematics> A portable hoisting apparatus, the same in principle as the differential windlass. A hoisting pulley to which power is applied through a differential gearing. Differential screw, a compound screw by which a motion is produced equal to the difference of the motions of the component screws. Differential thermometer, a thermometer usually with a U-shaped tube terminating in two air bulbs, and containing a coloured liquid, used for indicating the difference between the temperatures to which the two bulbs are exposed, by the change of position of the coloured fluid, in consequence of the different expansions of the air in the bulbs. A graduated scale is attached to one leg of the tube. Differential windlass, or Chinese windlass, a windlass whose barrel has two parts of different diameters. The hoisting rope winds upon one part as it unwinds from the other, and a pulley sustaining the weight to be lifted hangs in the bight of the rope. It is an ancient example of a differential motion. Origin: Cf. F. Differentiel. 1. <mathematics> An increment, usually an indefinitely small one, which is given to a variable quantity. According to the more modern writers upon the differential and integral calculus, if two or more quantities are dependent on each other, and subject to increments of value, their differentials need not be small, but are any quantities whose ratios to each other are the limits to which the ratios of the increments approximate, as these increments are reduced nearer and nearer to zero. 2. A small difference in rates which competing railroad lines, in establishing a common tariff, allow one of their number to make, in order to get a fair share of the business. The lower rate is called a differential rate. Differentials are also sometimes granted to cities. 3. <physics> One of two coils of conducting wire so related to one another or to a magnet or armature common to both, that one coil produces polar action contrary to that of the other. A form of conductor used for dividing and distributing the current to a series of electric lamps so as to maintain equal action in all. <mathematics> Partial differential, the differential of a function of two or more variables, when each of the variables receives an increment. The total differential of the function is the sum of all the partial differentials. Source: Websters Dictionary (01 Mar 1998) |
| differential adhesion | The differential adhesion hypothesis was advanced by Steinberg to explain the mechanism by which heterotypic cells in mixed aggregates sort out into isotypic territories. Quantitative differences in homo and hetero typic adhesion are supposed to be sufficient to account for the phenomenon without the need to postulate cell type specific adhesion systems: fairly generally accepted, although some tissue specific cell adhesion molecules are now known to exist. (18 Nov 1997) |
| differential blood pressure | The arterial blood pressure at corresponding points on the two sides of the body. (05 Mar 2000) |
| differential centrifugation | A technique for separating organellesor other differently-sized cellcomponents in a centrifuge, particles of the same size and weight willsettle out into common layers. (09 Oct 1997) |
| differential diagnosis | The determination of which two or more diseases with similar symptoms is the one from which a patient is suffering from based on an analysis of the clinical data. (27 Sep 1997) |
| differential display PCR | Method of image formation in the light microscope based on the method proposed by Nomarski (though strictly speaking all forms of optical microscopy rely to a greater or lesser extent on differential interference). The light beam is split by a Wollaston prism in the condenser, to form slightly divergent beams polarized at right angles. One passes through the specimen (and is retarded if the refractive index is greater) and one through the background nearby: the two are recombined in a second Wollaston prism in the objective and interfere to form an image. The image is spuriously three dimensional the nucleus, for example: appears to stand out above the cell (or be hollowed out) because it has a higher refractive index than the cytoplasm. The Nomarski system has the advantage that there is no phase halo, but the contrast is low and image formation with crowded cells is poor because the background does not differ from the specimen. (18 Nov 1997) |