| CIE | Canberra interview for the elderly; cellulose ion exchange; counter-current immunoelectrophoresis; c... |
|---|---|
| DIM | divalent ion metabolism; medium infective dose [Lat. dosis infectionis media] |
| FIM | field ion microscopy; functional independence measure |
| FU | fecal urobilinogen; fetal urobilinogen; fluorouracil; follow-up; flux unit [ion]; fractional urinaly... |
| H+ | hydrogen ion |
| ion pumps | Integral membrane proteins that transport ions across a membrane against an electrochemical gradient. (12 Dec 1998) |
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| ion selective electrode | An electrode half cell, with a semi permeable membrane that is permeable only to a single ion. The electrical potential measured between this and a reference half cell (e.g. A calomel electrode) is thus the Nernst potential for the ion. Given that the solution filling the ion selective electrode is known, the activity (rather than concentration) of the ion in the unknown solution can be measured. Commercial ion selective electrodes frequently use a hydrophobic membrane containing an ionophore, such as valinomycin (for potassium) or monensin (for sodium). A pH electrode is made with a thin membrane of pH sensitive (i.e. Proton permeable) glass. (18 Nov 1997) |
| ion-selective electrodes | Electrodes which can be used to measure the concentration of particular ions in cells, tissues, or solutions. (12 Dec 1998) |
| ion transport | The movement of ions across energy-transducing cell membranes. Transport can be active or passive. Passive ion transport (facilitated diffusion) derives its energy from the concentration gradient of the ion itself and allows the transport of a single solute in one direction (uniport). Active ion transport is usually coupled to an energy-yielding chemical or photochemical reaction such as ATP hydrolysis. This form of primary active transport is called an ion pump. Secondary active transport utilises the voltage and ion gradients produced by the primary transport to drive the cotransport of other ions or molecules. These may be transported in the same (symport) or opposite (antiport) direction. (12 Dec 1998) |
| oxonium ion | <chemistry> A positively charged ion that is water with an additional hydrogen atom (H3O). (09 Oct 1997) |
| tetraethylammonium ion | A monovalent cation widely used in neurophysiology as a specific blocker of potassium channels. It is similar in size to the hydrated potassium ion and gets stuck (reversibly) in the channels. (18 Nov 1997) |
| field ion microscope | <instrument> Type of microscopy in which the specimen is illuminated with ions, often gallium ions, that are focussed electrostatically. The ions remove components of the specimen, lower atomic masses first. These are imaged and provide information on elemental distribution with a resolution of perhaps 30 nm. (18 Nov 1997) |
| ligand gated ion channel | A transmembrane ion channel whose permeability is increased by the binding of a specific ligand, typically a neurotransmitter at a chemical synapse. The permeability change is often drastic, such channels let through effectively no ions when shut, but allow passage at up to 10exp7 ions sexp 1 when a ligand is bound. Recently, the receptors for both acetylcholine and GABA have been found to share considerable sequence homology, implying that there may be a family of structurally related ligand gated ion channels. (18 Nov 1997) |
| light-ion fusion | <radiobiology> Light-Ion-Beam-Driven Inertial Confinement fusion, using beams of light ions driven at implosion targets. Pulsed-power driven accelerators are relatively efficient and cost-effective, but beam-focusing is a technical hurdle for this approach. (09 Oct 1997) |
| air | 1. The fluid which we breathe, and which surrounds the earth; the atmosphere. It is invisible, inodourous, insipid, transparent, compressible, elastic, and ponderable. By the ancient philosophers, air was regarded as an element; but modern science has shown that it is essentially a mixture of oxygen and nitrogen, with a small amount of carbon dioxide, the average proportions being, by volume: oxygen.96 per cent.; nitrogen.00 per cent.; carbon dioxide.04 per cent. These proportions are subject to a very slight variability. Air also always contains some vapor of water. 2. Symbolically: Something unsubstantial, light, or volatile. "Charm ache with air." "He was still all air and fire. (Macaulay). [Air and fire being the finer and quicker elements as opposed to earth and water]" 3. A particular state of the atmosphere, as respects heat, cold, moisture, etc, or as affecting the sensations; as, a smoky air, a damp air, the morning air, etc. 4. Any aeriform body; a gas; as, oxygen was formerly called vital air. 5. Air in motion; a light breeze; a gentle wind. "Let vernal airs through trembling osiers play." (Pope) 6. Odouriferous or contaminated air. 7. That which surrounds and influences. "The keen, the wholesome air of poverty." (Wordsworth) 8. Utterance abroad; publicity; vent. "You gave it air before me." (Dryden) 9. Intelligence; information. 10. A musical idea, or motive, rhythmically developed in consecutive single tones, so as to form a symmetrical and balanced whole, which may be sung by a single voice to the stanzas of a hymn or song, or even to plain prose, or played upon an instrument; a melody; a tune; an aria. In harmonised chorals, psalmody, part songs, etc, the part which bears the tune or melody in modern harmony usually the upper part is sometimes called the air. 11. The peculiar look, appearance, and bearing of a person; mien; demeanor; as, the air of a youth; a heavy air; a lofty air. "His very air." 12. Peculiar appearance; apparent character; semblance; manner; style. "It was communicated with the air of a secret." (Pope) 12. An artificial or affected manner; show of pride or vanity; haughtiness; as, it is said of a person, he puts on airs. 14. The representation or reproduction of the effect of the atmospheric medium through which every object in nature is viewed. Carriage; attitude; action; movement; as, the head of that portrait has a good air. 15. The artificial motion or carriage of a horse. 16. To expose to the air for the purpose of cooling, refreshing, or purifying; to ventilate; as, to air a room. "It were good wisdom . . . That the jail were aired." (Bacon) "Were you but riding forth to air yourself." (Shak) 17. To expose for the sake of public notice; to display ostentatiously; as, to air one's opinion. "Airing a snowy hand and signet gem." (Tennyson) 18. To expose to heat, for the purpose of expelling dampness, or of warming; as, to air linen; to air liquors. Air is much used adjectively or as the first part of a compound term. In most cases it might be written indifferently, as a separate limiting word, or as the first element of the compound term, with or without the hyphen; as, air bladder, air-bladder, or airbladder; air cell, air-cell, or aircell; air-pump, or airpump. Air balloon. See Balloon. Air bath. An apparatus for the application of air to the body. An arrangement for drying substances in air of any desired temperature. Air castle. See Castle in the air, under Castle. Air compressor, a machine for compressing air to be used as a motive power. Air crossing, a passage for air in a mine. Air cushion, an air-tight cushion which can be inflated; also, a device for arresting motion without shock by confined air. Air fountain, a contrivance for producing a jet of water by the force of compressed air. Air furnace, a furnace which depends on a natural draft and not on blast. Air line, a straight line; a bee line. Hence Air-line,; as, air-line road. <medicine> Air lock Unsupported and liable to be turned or taken in flank; as, the army had its wing in the air. To take air, to be divulged; to be made public. To take the air, to go abroad; to walk or ride out. Origin: OE. Air, eir, F. Air, L. Aer, fr. Gr, air, mist, for, fr. Root to blow, breathe, probably akin to E. Wind. In sense 10 the French has taking a meaning fr. It. Aria atmosphere, air, fr. The same Latin word; and in senses 11, 12, 13 the French meaning is either fr. L. Aria, or due to confusion with F. Aire, in an older sense of origin, descent. Cf. Ary, Debonair, Malaria, Wind. Source: Websters Dictionary (01 Mar 1998) |
| air ambulances | Fixed-wing aircraft or helicopters equipped for air transport of patients. (12 Dec 1998) |
| air bags | Automotive safety devices consisting of a bag designed to inflate upon collision and prevent passengers from pitching forward. (12 Dec 1998) |
| air bladder | 1. <anatomy> An air sac, sometimes double or variously lobed, in the visceral cavity of many fishes. It originates in the same way as the lungs of air-breathing vertebrates, and in the adult may retain a tubular connection with the pharynx or oesophagus. 2. A sac or bladder full of air in an animal or plant; also an air hole in a casting. Source: Websters Dictionary (01 Mar 1998) |
| air-bone gap | The difference between the threshold for hearing acuity by bone conduction and by air conduction. (05 Mar 2000) |
| air bronchogram | Radiographic appearance of an air-filled bronchus surrounded by fluid-filled airspaces. (05 Mar 2000) |