822 resultados para sex allocation


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Occasional XY recombination is a proposed explanation for the sex-chromosome homomorphy in European tree frogs. Numerous laboratory crosses, however, failed to detect any event of male recombination, and a detailed survey of NW-European Hyla arborea populations identified male-specific alleles at sex-linked loci, pointing to the absence of XY recombination in their recent history. Here, we address this paradox in a phylogeographic framework by genotyping sex-linked microsatellite markers in populations and sibships from the entire species range. Contrasting with postglacial populations of NW Europe, which display complete absence of XY recombination and strong sex-chromosome differentiation, refugial populations of the southern Balkans and Adriatic coast show limited XY recombination and large overlaps in allele frequencies. Geographically and historically intermediate populations of the Pannonian Basin show intermediate patterns of XY differentiation. Even in populations where X and Y occasionally recombine, the genetic diversity of Y haplotypes is reduced below the levels expected from the fourfold drop in copy numbers. This study is the first in which X and Y haplotypes could be phased over the distribution range in a species with homomorphic sex chromosomes; it shows that XY-recombination patterns may differ strikingly between conspecific populations, and that recombination arrest may evolve rapidly (<5000 generations).

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Purpose: Plasma adiponectin and serum uric acid (SUA) levels are negatively correlated. To better understand the possible mechanisms linking adiponectin and uric acid, we analyzed whether the association between adiponectin and SUA differed by hypertension status (or blood pressure level) and by sex. Methods and materials: We analyzed data from the populationbased CoLaus study (Switzerland). Fasting plasma adiponectin levels were assessed by ELISA and SUA by uricase-PAP. Blood pressure (BP) was measured using a validated automated device and hypertension was defined as having office BP 140/90 mm Hg or being on current antihypertensive treatment. Results: In the 2897 men and 3181 women, aged 35-74, BMI (mean ± SD) was 26.6 ± 4.0 and 25.1 ± 4.8 Kg/m2, systolic blood pressure (SBP) was 132.2 ± 16.6 and 124.8 ± 18.3 mm Hg, median (interquartile range) plasma adiponectin was 6.2 (4.1-9.2) and 10.6 (6.9-15.4) mg/dL, and hypertension prevalence was 42.0% and 30.2%, respectively. The age- and BMI- adjusted partial correlation coefficients between log-adiponectin and SUA were 0.09 and 0.06 in normotensive men and women (P <0.01), and 0.004 (P = 0.88) and 0.15 (P <0.001) in hypertensive men and women, respectively. In median regression adjusted for BMI, insulin, smoking, alcohol consumption, menopausal status and HDL-cholesterol, there was a significant three-way interaction between SUA, SBP and sex for their effect on adiponectin (dependent variable, P = 0.005), as well as interactions between SBP and sex (P = 0.014) and between SUA and sex (P = 0.033). Conclusion: Plasma adiponectin and SUA are negatively associated, independently of BMI and insulin, in a population-based study in Caucasians. However, BP modifies this inverse relationship, as it was significant mainly in women with elevated BP. This observation suggests that the link between adiponectin and SUA may be mediated by sex hormones and the hypertension status.

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The following information is in this report produced by the CJJP: 1. Rate of reported rapes in Iowa, the west North Central states, and the U.S. 2. Statewide sex offense charges and convictions. 3. Iowa convictions for sex offenses, by class. 4. Sex offender prison and probation entries, FY2005. 5. Prison admissions for sex offenses, FY1995-2005. 6. Sex offender releases from Iowa prisons, 1990 and 1996-2005. 7. Three- year rates of sex offender recidivism. 8. Three- year rates of sex offender recidivism, by parolees and expiration.

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The Sex Offender Research Council was formed as a successor to the Sex Offender Treatment and Supervision Task Force, established to provide assistance to the General Assembly. It will respond to legislative direction to adjust its future plans as laid out in this report. Its plans could be modified to broaden or narrow its scope or to assign different priority levels of effort to its current areas of study. Also, further Council considerations of the recommendations it has already submitted could be called for. In the meantime, it is hoped that the information and recommendations submitted through this report prove helpful.

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The Sex Offender Research Council was formed as a successor to the Sex Offender Treatment and Supervision Task Force, established to provide assistance to the General Assembly. It will respond to legislative direction to adjust its future plans as laid out in this report. Its plans could be modified to broaden or narrow its scope or to assign different priority levels of effort to its current areas of study. Also, further Council considerations of the recommendations it has already submitted could be called for. In the meantime, it is hoped that the information and recommendations submitted through this report prove helpful.

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The Sex Offender Research Council was formed as a successor to the Sex Offender Treatment and Supervision Task Force, established to provide assistance to the General Assembly. It will respond to legislative direction to adjust its future plans as laid out in this report. Its plans could be modified to broaden or narrow its scope or to assign different priority levels of effort to its current areas of study. Also, further Council considerations of the recommendations it has already submitted could be called for. In the meantime, it is hoped that the information and recommendations submitted through this report prove helpful.

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Abstract: Ideological stability and change in Finland : an analysis of party programmes

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Sex determination is often seen as a dichotomous process: individual sex is assumed to be determined either by genetic (genotypic sex determination, GSD) or by environmental factors (environmental sex determination, ESD), most often temperature (temperature sex determination, TSD). We endorse an alternative view, which sees GSD and TSD as the ends of a continuum. Both effects interact a priori, because temperature can affect gene expression at any step along the sex-determination cascade. We propose to define sex-determination systems at the population- (rather than individual) level, via the proportion of variance in phenotypic sex stemming from genetic versus environmental factors, and we formalize this concept in a quantitative-genetics framework. Sex is seen as a threshold trait underlain by a liability factor, and reaction norms allow modeling interactions between genotypic and temperature effects (seen as the necessary consequences of thermodynamic constraints on the underlying physiological processes). As this formalization shows, temperature changes (due to e.g., climatic changes or range expansions) are expected to provoke turnovers in sex-determination mechanisms, by inducing large-scale sex reversal and thereby sex-ratio selection for alternative sex-determining genes. The frequency of turnovers and prevalence of homomorphic sex chromosomes in cold-blooded vertebrates might thus directly relate to the temperature dependence in sex-determination mechanisms.

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The programs included in this Discussion Paper no. 17 are Distance, Unravel, Retrench and Alloc 6B that deal with location-allocation analyses first published in 1973 by the Department of Geography, The University of Iowa.

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