introduction: inequality is prevalent in all sectors, particularly in distribution of and access to resources in the health sector. the aim of current study was to investigate the distribution of physicians and hospital beds in iran in 2001, 2006 and 2011. methods: this retrospective, cross-sectional study evaluated the distribution of physicians and hospital beds in 2001, 2006 and 2011 using g...

We obtain closed form expressions for the expected conditional degree distribution and the joint degree distribution of the linear preferential attachment model for network growth in the steady state. We consider the multiple-destination preferential attachment growth model, where incoming nodes at each timestep attach to β existing nodes, selected by degree-proportional probabilities. By the c...

The consistency of the species abundance distribution across diverse communities has attracted widespread attention. In this paper, I argue that the consistency of pattern arises because diverse ecological mechanisms share a common symmetry with regard to measurement scale. By symmetry, I mean that different ecological processes preserve the same measure of information and lose all other inform...

This paper introduces an alternative approach to relieving the task of choosing optimal mutation and crossover rates by using a parallel and distributed GA with distributed environments. It is shown that the best mutation and crossover rates depend on the population sizes and the problems, and those are different between a single and multiple populations. The proposed distributed environment GA...

MRAG Americas, P.O.B. 1410, Capitola, CA 95010, United States Center for Stock Assessment Research, University of California, Santa Cruz, 1156 High St., Santa Cruz, CA 95064, United States c Fisheries Ecology Division, Southwest Fisheries Science Center, National Marine Fisheries Service, 110 Shaffer Road, Santa Cruz, CA 95060, United States d Institute of Marine Sciences, University of Califor...

A simple argument based on the distribution of individuals amongst discrete resource sites is used to show how the form of single species population models depends on the type of competition between, and the spatial clustering of, the individuals. For scramble competition between individuals, we confirm earlier demonstrations that the Ricker model is a direct consequence of a uniform random dis...

background: cytochrome p450 2c19 (cyp2c19) is important in metabolism of wide range of drugs. cyp2c19*17 is a novel variant allele which increases gene transcription and therefore results in ultra-rapid metabolizer phenotype (urm). distribution of this variant allele has not been well studied worldwide. the aim of present study was to investigate allele and genotype frequencies of cyp2c19*17 in...

the population density and spatial distribution pattern of empoasca decipiens paoli were etermined in tehran area, iran, during 2004-2005 on four species of common bean phaseolus vulgaris (l.) var. talash, lima bean p. lunatus (l.) savi ex hassk. var. sadaf, rice bean p. calcaratus roxb. var. goli and cowpea vigna sinensis (l.) var. parastoo. the higher and lower mean population densities of e....

population density and spatial distribution of thrips tabaci lindeman on seven soybean varieties (williams, tellar, sahar, dpx, l17, sari and zane) and one genotype (ks3494) were studied in tehran region, during 2007. the highest population density of the thrips per leaf was recorded on dpx and on ks3494 (0.810.05 and 0.800.05, respectively). the lowest population density was observed on l17 ...

the population densities and spatial distribution patterns of zetzellia pourmirzai khanjani and ueckermann and its preys cenopalpus irani dosse and bryobia rubrioculus (scheuten) were studied in a sprayed orchard in kermanshah, a western province of iran, from 31 may till 7 november, 2007. the interaction (density dependence) between the plant feeding mites and their predator was determined as ...