selection

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Related to selection differential: heritability, selection intensity

se·lec·tion

(sĕ-lek'shŭn),
The combined effect of the causes and consequences of genetic factors that determine the average number of progeny of a species that attain sexual maturity; phenotypes that are lethal early in life (for example, Tay-Sachs disease), that cause sterility (for example, Turner syndrome), or that produce sterile progeny are selected against. When selection is used of individual pedigrees, other factors, notably variance of the number of progeny and number that survive to maturity, are important considerations; in large populations, these factors even out and the mean only is of importance.
[L. se-ligo, to separate, select, fr. se, apart, + lego, to pick out]

selection

(sĭ-lĕk′shən)
n.
Biology A natural or artificial process that involves the survival and reproduction of some kinds of organisms instead of others (because they have traits that are better adapted to the environment or that are preferred by a breeder, for example) and results in changes in the traits of a population or species.

se·lec′tion·al (-shə-nəl) adj.

selection

Vox populi The chosing among a number of different options. See Adverse selection, Artificial selection, Group selection, Kin selection, Negative selection, Patient selection, Sex selection.

se·lec·tion

(sĕ-lek'shŭn)
The combined effect of the causes and consequences of genetic factors that determine the average number of progeny of a species that attain sexual maturity.
[L. se-ligo, to separate, select, fr. se, apart, + lego, to pick out]

selection

the differential rate of reproduction of one phenotype in a population as compared to other phenotypes. Hence an organism that produces more offspring which survive to reproduce than another type is at a ‘selective advantage’. The environmental pressures causing selection can be either natural (e.g. competition for food) or artificial (e.g. insecticides, see DDT). See DIRECTIONAL SELECTION, NATURAL SELECTION, STABILIZING SELECTION.

se·lec·tion

(sĕ-lek'shŭn)
The combined effect of the causes and consequences of genetic factors that determine the average number of progeny of a species that attain sexual maturity.
[L. se-ligo, to separate, select, fr. se, apart, + lego, to pick out]

Patient discussion about selection

Q. clonex symptoms in Selective Mutism Syndrome children My son is 6.5 years old, with selective mutism syndrome - in a months time he shall be entering first grade. We have, the past 2 years been with therapists specializing in this field. He has improved outside a closed system i.e. within the kindergarten (primarily) we even see some regression. We have been at major dilemmas with giving him medication but due to the critical time - we were recommended to take 0.125 mg of Clonex medication. we are a little worried and would like to understand the possible symptoms

A. As a benzodiazepin, it can cause drowsiness, weakness and other changes in behavior. There may be some other side-effects, that you can read about here (http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a682279.html)

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References in periodicals archive ?
Selection differentials in milk production traits were generally greater than those of conformation traits in all four paths of selection and throughout the entire study period (1993-2012).
Selection differentials generally increased as more harvests were included in the selection criterion, by 3.1 [+ or -] 0.5 and 2.7 [+ or -] 0.5 g [kg.sup.-1] [harvest.sup.-1] for one-block and two-block selection criteria, respectively (Table 2).
As with M, the M/K ratio affects other parameters; therefore changes in M/K could be expected to produce a nonlinear response in the selection differentials. The percent selection differential on [L.sub.[infinity]] was lowest at an intermediate value of M/ K=2 (Table 3).
It was observed that the genetic gain among families was higher compared to the gain within families for both traits, although the selection differential within families ([SD.sub.fs]) was superior to the differential among families ([SD.sub.f]).
One population, Lincoln, had a significant positive selection differential (Table 5) and two populations had a significant negative selection differential for marker index 5 (MI-5).
The selection differentials for flower-opening date were negative and statistically significant for female, male, and total pollination success at Hemlock Ravine (Table 4).
The genotype x year variance was highly significant, but comparing selection differentials obtained by selecting [S.sub.1] families on the basis of 1- and 2-yr data indicated that single-year evaluations would yield good selection gains.
In appendix C, expansions are given for the selection differential [S.sub.i], and the covariance after selection [[C.sub.ij].sup.*] (see eq.
The realized heritability ([h.sup.2]) of development time was calculated from the ratio of total selection response (R) to total selection differential (S) after six generations of divergent selection (Hill 1972): [[h.sup.2].sub.DT] = R/S.
Pollen export to recipient stigmas increased with the width of donor flowers [ILLUSTRATION FOR FIGURE 2 OMITTED], and the standardized selection differential S[prime] for total visit effectiveness was 0.38 ([F.sub.1,18] = 7.26, P [less than] 0.01).
The average selection differential of the two procedures was 8.2 and 10.5 g [kg.sup.-1], respectively.

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