| S value | Svedberg Unit. See: sedimentation coefficient. (18 Nov 1997) |
|---|---|
| iodine value | An indication of the quantity of unsaturated fatty acids present in a fat; it represents the number of grams of iodine absorbed by each 100 g of fat. See: hydrogen number. Synonym: iodine value. (05 Mar 2000) |
| tenth-value layer | <radiobiology> Thickness of a specified substance which, when introduced into the path of a given beam of radiation, reduces the absorbed dose index or dose-equivalent index to one-tenth. The magnitude of the tenth-value layer may be different for absorbed dose index and dose equivalent index. (16 Dec 1997) |
| thiocyanogen value | The number of grams of thiocyanogen taken up by 100 g of fat; analogous to the iodine number, except that thiocyanogen will not add to all the double bonds in polyunsaturated fatty acids as will iodine. Synonym: thiocyanogen value. (05 Mar 2000) |
| threshold limit value | The maximum concentration of a chemical recommended by the American Conference of Government Industrial Hygienists for repeated exposure without adverse health effects on workers. (05 Mar 2000) |
| law of initial value | The direction of response of a body function to any agent depends to a large degree on the initial level of that function. Synonym: law of initial value. (05 Mar 2000) |
| lower heating value | (LHV) The potential energy in a fuel if the water vapour from combustion of hydrogen is not condensed. (05 Dec 1998) |
| advanced life support | Definitive emergency medical care that includes defibrillation, airway management, and use of drugs and medications. Compare: basic life support. (05 Mar 2000) |
| artificial life | Artificial life (AL, alife) is a scientific discipline in whichresearchers study life by creating computer programs that recreatebiological systems from scratch. (09 Oct 1997) |
| basic life support | Emergency cardiopulmonary resuscitation, control of bleeding, treatment of shock, acidosis, and poisoning, stabilization of injuries and wounds, and basic first aid. (05 Mar 2000) |
| biological half-life | <biochemistry, biology> This is the time required for one-half of the total amount of a particular substance in a biological system to be consumed or broken down by biological processes when the rate of removal is approximately exponential. Toxic chemicals with a long biological half-life (such as some pesticides) will tend to accumulate in the body and are, therefore, more likely to be harmful. A substance with a short biological half-life may still accumulate if a portion of it it becomes tightly bound to bone or other tissues, even if most of it is quickly cleared from the body. (21 Mar 1998) |
| vegetative life | The simple metabolic and reproductive activity of humans or animals, apart from the exercise of conscious mental or psychic processes. (05 Mar 2000) |
| germ-free life | Animals not contaminated by or associated with any foreign organisms. (12 Dec 1998) |
| change of life | Colloquialism for menopause, climacteric. (05 Mar 2000) |
| RNA life | <biology, molecular biology> A hypothetical life form lacking DNA and protein which may have existed on early earth and in which RNA served both a genetic coding and a catalytic function. (23 Aug 1998) |