| field of view | <microscopy> The extent of the visible image field that can be seen. (05 Aug 1998) |
|---|---|
| field planes | <microscopy> The set of planes in a microscope adjusted for Kohler illumination that are conjugate with the focused specimen. They include the plane of the specimen, the field diaphragm, the intermediate image plane, and the image on the retina, photographic emulsion, or the faceplate of the video pickup device. (05 Aug 1998) |
| field-reversed configuration | <radiobiology> A compact torus produced in a theta pinch and having (in principle) no toroidal field. The potential advantages for a fusion reactor include a simple (linear) machine geometry, an average plasma pressure close to the confining field pressure, and physical separation of formation and burn chambers. The are predicted to be violently unstable to tilting, but this is rarely observed. (09 Oct 1997) |
| field shaping coils | <radiobiology> Type of poloidal field coils (in a tokamak) which create magnetic fields which shape and control the plasma. Used to constrain horizontal and vertical displacements of the plasma, as well as (in some configurations) produce non-circular plasma cross-sections (poloidal cross-section) and/or create one or more divertor separatrices. (09 Oct 1997) |
| field survey | The planned collection of data among noninstitutionalised persons in the general population. (05 Mar 2000) |
| field-vole | A species of field mouse (Microtus montebelloi), normal host of Leptospira hebdomadis, the cause of a type of leptospirosis resembling infectious mononucleosis. (05 Mar 2000) |
| free field | A field (three-dimensional space) in a homogeneous, isotropic medium free from boundaries; in practice, a field in which boundary effects are negligible. (05 Mar 2000) |
| Abbott's stain | <technique> Spores are stained blue with alkaline methylene blue; bodies of the bacilli become pink with eosin counterstain. (05 Mar 2000) |
| aceto-orcein stain | <technique> A stain used for chromosomes in air-dried or squashed cytologic material. (05 Mar 2000) |
| acid-fast stain | <technique> A staining technique used to determine the cell wall property of a microorganism. After stained with dye such as hot carbolfuschin, an acid-fast organism, (for example Mycobacterium species) will retain the colour in its cell wall after being washed with acid-alcohol. (13 Nov 1997) |
| acid stain | <technique> A dye in which the anion is the coloured component of the dye molecule, e.g., sodium eosinate (eosin). (05 Mar 2000) |
| Ag-AS stain | <technique> A stain for the acid protein component of nucleolar regions which are active or which were transcriptionally active in the preceding interphase; uses silver nitrate, ammoniacal silver, and formalin. Synonym: Ag-AS stain. (05 Mar 2000) |
| Albert's stain | <technique> A stain for diphtheria bacilli and their metachromatic granules; contains toluidine blue, methyl green, glacial acetic acid, alcohol, and distilled water. (05 Mar 2000) |
| Altmann's anilin-acid fuchsin stain | <technique> A mixture of picric acid, anilin, and acid fuchsin which stains mitochondria crimson against a yellow background. (05 Mar 2000) |
| auramine O fluorescent stain | <technique> A rapid and accurate technique for Mycobacterium tuberculosis, using auramine O-phenol and a methylene blue counterstain. (05 Mar 2000) |