| Douglas' spontaneous evolution | A mechanism whereby molding of the foetus and impaction of the shoulder and prolapsed arm occurs in transverse lie, allowing vaginal delivery with the lateral aspect of the thorax following the prolapsed shoulder. (05 Mar 2000) |
|---|---|
| quantum evolution | An extremely rapid evolutionarychange in a single genetic lineage, thought to result from a sudden and radical change in the species'environment. (09 Oct 1997) |
| organic evolution | Biologic evolution was contrasted with cultural evolution in 1968 by A.G. Motulsky who pointed out that biologic evolution is mediated by genes, shows a slow rate of change, employs random variation (mutations) and selection as agents of change, new variants are often harmful, these new variants are transmitted from parents to offspring, the mode of transmission is simple, complexity is achieved by the rare formation of new genes by chromosome duplication, biologic evolution occurs with all forms of life, and the biology of humans requires cultural evolution. See Cultural evolution. (12 Dec 1998) |
| emergent evolution | Appearance of a property in a complex system e.g., organism that could have been predicted only with difficulty, or perhaps not at all, from a knowledge and understanding of the individual genotype changes taken separately. (05 Mar 2000) |
| evolution | 1. An unrolling. 2. A process of development in which an organ or organism becomes more and more complex by the differentiation of its parts, a continuous and progressive change according to certain laws and by means of resident forces. Origin: L. Evolutio (18 Nov 1997) |
| evolution, biologic | A.G. Motulsky in 1968 contrasted biologic evolution with cultural evolution, pointing out that biologic evolution is mediated by genes, shows a slow rate of change, employs random variation (mutations) and selection as agents of change, new variants are often harmful, these new variants are transmitted from parents to offspring, the mode of transmission is simple, complexity is achieved by the rare formation of new genes by chromosome duplication, biologic evolution occurs with all forms of life, and the biology of humans requires cultural evolution. See Evolution, cultural. (12 Dec 1998) |
| evolution, chemical | Chemical and physical transformation of the biogenic elements from their nucleosynthesis in stars to their incorporation and subsequent modification in planetary bodies and terrestrial biochemistry. It includes the mechanism of incorporation of biogenic elements into complex molecules and molecular systems, leading up to the origin of life. (12 Dec 1998) |
| evolution, cultural | By contrast with biologic evolution, A.G. Motulsky in 1968 pointed out that social evolution is mediated by ideas, shows a rapid (exponential) rate of change, is usually purposeful, often beneficial, is widely disseminated by diverse means, is frequently transmitted in complex ways, further complexity comes from the frequent formation of new ideas and new technologies. Cultural evolution is unique to humans among all forms of life. Human culture required biologic evolution to achieve the human brain. See Evolution, social. (12 Dec 1998) |
| evolution, planetary | Creation and development of bodies within solar systems, includes study of early planetary geology. (12 Dec 1998) |
| Armillaria mellea neutral proteinase | <enzyme> Specific for lysine Registry number: EC 3.4.99.32 (26 Jun 1999) |
| ribosomal neutral proteinase | <enzyme> Ribosomal serine proteinase from rat liver ribosomes in cryptic form Registry number: EC 3.4.21.52 Synonym: cathepsin r (26 Jun 1999) |
| Staphylococcal neutral phosphatase | <enzyme> A surface-bound bacterial protein; highly cationic; shows maximum phosphatase activity at neutral pH; binds to immunoglobulin Registry number: EC 3.1.3.- Synonym: staphylococcal nptase, nptase (26 Jun 1999) |
| Staphylococcus aureus neutral proteinase | <enzyme> Included in the group of microbial metalloproteinases EC 3.4.24.4; ptrb protein is isolated from E coli; sakstar is recombinant staphylokinase Pharmacological action: fibrinolytic agents Registry number: EC 3.4.24.- Synonym: protease II, staphylokinase, staph aureus protease, staphylococcal protease, E coli protease, ptrb protein, sakstar, (26 Jun 1999) |
| neutral | 1. Not engaged on either side; not taking part with or assisting either of two or more contending parties; neuter; indifferent. "The heart can not possibly remain neutral, but constantly takes part one way or the other." (Shaftesbury) 2. Neither good nor bad; of medium quality; middling; not decided or pronounced. "Some things good, and some things ill, do seem, And neutral some, in her fantastic eye." (Sir J. Davies) 3. <biology> Neuter. See Neuter. 4. <chemistry> Having neither acid nor basic properties; unable to turn red litmus blue or blue litmus red; said of certain salts or other compounds. Contrasted with acid, and alkaline. <chemistry> Neutral axis, Neutral surface, a salt formed by the complete replacement of the hydrogen in an acid or base; in the former case by a positive or basic, in the latter by a negative or acid, element or radical. Neutral tint, a bluish gray pigment, used in water colours, made by mixing indigo or other blue some warm colour. The shades vary greatly. Neutral vowel, the vowel element having an obscure and indefinite quality, such as is commonly taken by the vowel in many unaccented syllables. It is regarded by some as identical with the u in up, and is called also the natural vowel, as unformed by art and effort. Origin: L. Neutralis, fr. Neuter. See Neuter. Source: Websters Dictionary (01 Mar 1998) |
| neutral axis of straight beam | The axis perpendicular to the plane of loading of a beam at stresses within the proportional limit; it lies at the gravity axis of the cross-section of the beam. (05 Mar 2000) |