| soil profile | A vertical section of the soil through all its horizons and extending into the parent material. (09 Oct 1997) |
|---|---|
| soil series | A group of soils having horizons similar in differentiating characteristics and arrangements in the soil profile, except for texture of the surface layer. (09 Oct 1997) |
| soil structure | The combination or arrangement of primary soil particles into secondary particles, units or peds. (09 Oct 1997) |
| soil suborder | Second highest taxonomic level of the current U.S. Soil classification system. (09 Oct 1997) |
| soil surface | The upper limits of the soil profile, for mineral soils, the upper limits of the highest mineral horizon (A-horizon), for organic soils, the upper limit of undecomposed organic matter. (09 Oct 1997) |
| soil texture | The relative proportions of the various sizes of particles (silt, sand and clay) in a soil. (09 Oct 1997) |
| soil value | The relative lightness or intensity of colour, approximately a function of the square root of the total amount of light, one of the three variables of colour. (09 Oct 1997) |
| somewhat poorly drained soil | <botany> A condition in which water is removed slowly enough that the soil is wet for significant periods during the growing season. (04 Mar 1998) |
| expansive soil | Soils that swell when they absorb water and shrink as they dry. (09 Oct 1997) |
| accelerated phase of leukaemia | Refers to chronic myelogenous leukaemia that is progressing. The number of immature, abnormal white blood cells in the bone marrow and blood is higher than in the chronic phase, but not as high as in the blast phase. (12 Dec 1998) |
| acceleration phase | <cell biology, cell culture> A period of increasing growth before the log phase in a culture of microbes. After the culture is started on a medium, at first there is no growth (the lag phase) and then the microbes start to gradually grow (acceleration phase) until they reach a constant maximum rate of growth (log phase). (15 Jan 1998) |
| acute-phase protein | <haematology> These plasma proteins (in addition to fibrinogen) increase 25% or more in response to inflammation and injury are under direct control of interleukin-6 (IL-6) (hepatocyte-stimulating factor). Other proteins which increase are ceruloplasmin, C3 and C4 which increase 50% or more; alpha-1 acid glycoprotein, alpha-1 antitrypsin, haptoglobin and fibrinogen (the major determinant of viscosity 1 ) which increase two- to fourfold; C-reactive protein (CRP) and serum amyloid A which increase several hundred-fold. Despite long-held clinical opinion to the contrary, available data indicate that neither ESR nor measurement of specific acute-phase reactants are useful in excluding underlying infection or inflammation regardless of the pretest probability. These proteins are secreted into the blood in increased or decreased quantities by hepatocytes in response to trauma, inflammation, or disease. They can serve as inhibitors or mediators of the inflammatory processes. Certain acute-phase proteins have been used to diagnose and follow the course of diseases or as tumour markers. See also: amyloid, c-reactive protein, erythrocyte sedimentation rate, viscosity. (25 Jun 1999) |
| acute-phase reaction | <immunology, rheumatology> Refers to the changes in synthesis of certain proteins within the serum during an inflammatory response, which provides rapid protection for the host against microorganisms via non-specific defense mechanisms. It consists of fever, an increase in inflammatory humoral factors, and an increased synthesis by hepatocytes of a number of proteins or glycoproteins usually found in the plasma; the reaction is mediated by endogenous pyrogens, the hypothalamus, adrenal hormones, and other factors. (12 Jul 2000) |
| anal phase | In psychoanalytic personality theory, the stage of psychosexual development, occurring when a child is between 1 and 3 years, during which activities, interests, and concerns are centreed around the anal zone. (05 Mar 2000) |
| aqueous phase | The water portion of a system consisting of two liquid phase's, one mainly water, the other a liquid immiscible with water (e.g., benzene, ether). (05 Mar 2000) |