| Vf | 1) Ventricular flutter 2) Visual field |
|---|---|
| VFD | Visual Field Defect |
| AREDYLD | acrorenal field defect, ectodermal dysplasia, lipoatrophic diabetes [syndrome] |
| B0 | constant magnetic field in nuclear magnetic resonance |
| Bo | constant magnetic field in a magnetic resonance scanner |
| constant field equation | An equation derived to predict membrane potentials in terms of the membrane's permeability to ions and their concentrations on either side. Synonym: constant field equation, Goldman-Hodgkin-Katz equation, GHK equation. (05 Mar 2000) |
|---|---|
| poloidal field | <physics> In toroidal devices, the magnetic field that encircles the plasma axis. (i.e., loops around the torus the short way.) (09 Oct 1997) |
| poloidal field coil | <radiobiology> In toroidal devices (e.g., tokamaks), the sets of windings which are (typically) aligned along the plasma axis and produce poloidal fields. These include ohmic heating, shaping, vertical, equilibrium, and divertor windings. (09 Oct 1997) |
| curvature of field | <microscopy> A property of lens that causes the image of a plane to be focused into a curved surface instead of a plane. The image plane formed by a single lens is naturally curved. While one part of the field will be in good focus, the rest will need refocusing to be sharp. While the eye may partially correct for this, a camera lens will not, and the final image as photographed will not be in perfect focus over the entire image plane. (05 Aug 1998) |
| prerubral field | See: fields of Forel. (05 Mar 2000) |
| pulsed-field gel electrophoresis | Gel electrophoresis in which, after electrophoretic migration has begun, the current is briefly stopped and reapplied in a different orientation; allows for the purification of long DNA molecules. Synonym: pulsed-field gel electrophoresis. (05 Mar 2000) |
| pulse field electrophoresis | <investigation> A method used for high resolution electrophoretic separation of very large (megabase) fragments of DNA. Electric fields 100 |
| pulse-field gel electrophoresis | Gel electrophoresis in which, after electrophoretic migration has begun, the current is briefly stopped and reapplied in a different orientation; allows for the purification of long DNA molecules. Synonym: pulsed-field gel electrophoresis. (05 Mar 2000) |
| nerve field | The regional distribution of nerve terminals. (05 Mar 2000) |
| depth of field | <microscopy> The depth or thickness of the object space that is simultaneously in acceptable focus. The distance between the closest and farthest objects in focus within a scene as viewed by a lens at a particular focus and with given settings. The depth of field varies with the focal length of the lens and its f-stop setting or numerical aperture, and the wavelength of light. Depth of fields only a small fraction of a micrometre can be achieved at 546 nm with microscope lenses of N.A. Greater than 0.9. (05 Aug 1998) |
| image field | <microscopy> Any field showing a focused image. There are a number of such fields in the complete microscopical system. The term may also denote the field of view, or the image field at the focal plane of the camera, generally the field where the final image is formed. (05 Aug 1998) |
| individuation field | The field within which an organiser can bring about the rearrangement of primordial tissues in such a manner that a complete embryo is formed. (05 Mar 2000) |
| object field | <microscopy> A position lying in the front focal plane of the objective. (05 Aug 1998) |
| electric field | <radiobiology> A property of a patch of space which causes the acceleration of electric charges located at that patch of space. The acceleration is given by a = qE/m, where q is the charge, E the electric field vector, and m the mass of the particle. Electric fields are generated by the presence of charges and/or the time variation of magnetic fields (09 Oct 1997) |
| electrophoresis, gel, pulsed-field | Electrophoresis in which the direction of the electric field is changed periodically. This technique is similar to other electrophoretic methods normally used to separate double-stranded DNA molecules ranging in size up to tens of thousands of base-pairs. However, by alternating the electric field direction one is able to separate DNA molecules up to several million base-pairs in length. (12 Dec 1998) |