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Different Environmental (different + environmental)
Terms modified by Different Environmental Selected AbstractsSex differences in genetic and environmental determinants of pulse pressureGENETIC EPIDEMIOLOGY, Issue 5 2006Katrina J. Scurrah Abstract Pulse pressure (PP) is an independent risk factor for cardiovascular disease. PP rises with age, more so in women. We examined sex differences in the correlations and variance components of PP in adult subjects from 767 nuclear families, enriched with those containing twins, from the Victorian Family Heart Study. After adjusting for age, we found no significant differences in the means or variances of PP in males and females. Under the assumption of no sex differences, the proportions of variance due to shared genes, shared environment, and individual-specific environment were 20%, 23% and 57%, respectively. However, same-sex relative pairs had significantly higher correlations than opposite-sex pairs (P=0.005), implying the existence of sex-dependent effects. Extensions to the simple variance components model suggested three possible explanations for these differences: smaller genetic correlation between opposite-sex pairs (,G,MF=0.45, P=0.007); smaller environmental correlation between opposite-sex pairs (P=0.0003); or different environmental and genetic correlations obtained by estimating genetic, environmental, and individual variance components separately for males and females (not nested, Akaike's Information Criterion (AIC) smaller by 6.69). Under the last model, the genetic component of PP variance is greater for males (1.62 vs 0.33) while the environmental component is greater for females (1.84 vs 0), which would have implications for the planning of gene discovery studies, since heritability would be higher in males. However, the second (environmental) approach best fits the data according to the AIC. Genetic explanations for sex differences in phenotypic correlations may be misleading unless shared environmental factors are also considered. PP illustrates a phenotype in which sex dependency represents an important component of phenotypic determination that can be revealed by detailed variance components modelling. Genet. Epidemiol. 2006. © 2006 Wiley-Liss, Inc. [source] Genetic diversity and structure of the West Balkan Pramenka sheep types as revealed by microsatellite and mitochondrial DNA analysisJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 6 2008inkulov Summary Several different phenotypes of the native Pramenka sheep have been developed in the Balkan region for different environmental and socio-cultural conditions. Animals from seven West Balkan Pramenka sheep types were analysed for 15 microsatellite markers and for mitochondrial DNA (mtDNA) and the results were used to assess genetic variation within and among the types and to infer the genetic population structure of the Pramenka sheep. Mean expected heterozygosity and allelic richness over the microsatellite loci and sheep types were 0.78 and 7.9, respectively. A Bayesian statistical method for estimating hidden genetic structure suggested that a core of the largest panmictic population was formed by Serbian, Kosovan, Bosnian, Montenegrin and Albanian types, while Croatian and Macedonian types comprised two other main populations, respectively. Mitochondrial DNA analysis revealed two mtDNA haplogroups in the Pramenka sheep, B and A, with a frequency of 93.7% and 6.3%, respectively. A total of 60 mtDNA haplotypes were found in 64 animals sequenced, and the mean nucleotide and haplotypic diversities over the types were 0.013 and 0.945, respectively. Molecular analysis suggests that the West Balkan Pramenka sheep types have their origins in two distinct maternal lineages of domestic sheep and different Pramenka phenotypes tend to form few panmictic populations. The Pramenka sheep represents a valuable resource of genetic diversity in sheep. [source] Double staining protocol for developing European sea bass (Dicentrarchus labrax) larvaeJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2010M. J. Darias Summary The alcian blue-alizarin red technique was successfully adjusted to stain developing European sea bass (Dicentrarchus labrax) larvae. For an optimal staining protocol design both larval size and their morphological characteristics at each developmental stage were considered, since such parameters notably influence the staining of tissues. The incubation times of the different solutions were adjusted to allow the stain penetration for revealing the integrity of cartilaginous and bony tissues without significant tissue degradation. Three developmental windows were determined for an optimal staining procedure: (i) 4.5,6.4 mm, (ii) 6.7,8.7 mm, and (iii) 12.8,15.5 mm total length (TL). In order to validate the continuity of staining along the larval development, quantification of bone mineralization and osteocalcin gene expression were also monitored. Quantitative analysis revealed that ossification followed an exponential kinetic that was positively correlated with the osteocalcin gene expression pattern (Rs = 0.9762, P < 0.05). The mineralized tissue increased from 6.4 mm TL onwards, corresponding with the detection of the first ossified structures. The quantity of bony tissue increased gradually until 7.6 mm TL, since mineralization remained limited to the skull. From 8.3 to 15.5 mm TL, the mineralized bone was notable and nearly concerned the whole larval skeleton (skull, vertebral column and caudal complex). Since it was possible to detect the first cartilaginous and mineralized structures in specimens as small as 4.5 and 6.4 mm TL, respectively, this procedure is a useful tool to study the European sea bass skeletal ontogenesis, to precociously diagnose skeletal malformations in small larvae and eventually to better characterize the effect of different environmental and/or nutritional factors on the ossification status of specific skeletal components. [source] Dust mite infestation of flour samplesALLERGY, Issue 12 2009F. C. Yi Background:, Ingestion of flour contaminated with dust mite may trigger severe anaphylaxis in tropical and sub-tropical regions. Aims:, This study aimed to evaluate environmental factors that affect dust mite propagation in the tropics. Materials & Methods:, Dust mites were introduced to a variety of flour samples and incubated at two different environmental conditions. Results: It was found that dust mites populations flourished best in wheat flour compared to other varieties of flour, and at ambient temperatures with high humidity instead of the air conditioned environment. Conclusion:, Dust mite infestation of flour is dependent on the presence of wheat and high ambient temperature in the tropics. [source] Climate variables as predictors of basal metabolic rate: New equationsAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2008Andrew W. Froehle Estimation of basal metabolic rate (BMR) and daily energy expenditure (DEE) in living humans and in fossil hominins can be used to understand the way populations adapt to different environmental and nutritional circumstances. One variable that should be considered in such estimates is climate, which may influence between-population variation in BMR. Overall, populations living in warmer climates tend to have lower BMR than those living in colder climates, even after controlling for body size and composition. Current methods of estimating BMR ignore climate, or deal with its effects in an insufficient manner. This may affect studies that use the factorial method to estimate DEE from BMR, when BMR is not measured but predicted using an equation. The present meta-analysis of published BMR uses stepwise regression to investigate whether the inclusion of climate variables can produce a generally applicable model for human BMR. Regression results show that mean annual temperature and high heat index temperature have a significant effect on BMR, along with body size, age and sex. Based on the regression analysis, equations predicting BMR from body size and climate variables were derived and compared with existing equations. The new equations are generally more accurate and more consistent across climates than the older ones. Estimates of DEE in living and fossil humans using the new equations are compared with estimates using previously published equations, illustrating the utility of including climate variables in estimates of BMR. The new equations derived here may prove useful for future studies of human energy expenditure. Am. J. Hum. Biol., 2008. © 2008 Wiley-Liss, Inc. [source] Linkages between household wealth, bushmeat and other animal protein consumption are not invariant: evidence from Rio Muni, Equatorial GuineaANIMAL CONSERVATION, Issue 6 2009J. E. Fa Abstract Bushmeat consumption is affected by household wealth. However, how household wealth impacts bushmeat eaten in different environmental and social settings (i.e. whether urban, rural, coastal or forest) is poorly understood. In this study, we sampled households in six contrasting localities in Rio Muni, Equatorial Guinea, in coastal (Bata, Cogo), central (Niefang, Evinayong) and eastern parts of the territory (Ebebiyin, Nsork). On average, 32.3 g of bushmeat per adult male equivalent per day were consumed, though this varied widely between sites and most households ate no bushmeat on the survey day. Fish was the most frequently recorded source of protein and in a coastal site, Cogo, significantly more fish was consumed than in the other localities. Overall, average protein consumption was correlated with household wealth, but the strength of this effect varied among sites. At the site where average wealth was highest (Bata, the most urban site), bushmeat was more expensive, and wealthier households ate more of it. Elsewhere bushmeat consumption was not associated with wealth, and the cost of bushmeat was a higher proportion of household wealth. In Bata, wealthier households reported consumption of more than one meat type (most frequently bushmeat and either domestic meat or fish), and diversity of dietary items also increased with wealth. In all sites, wealthier households ate less fish. We demonstrate distinct differences in relationships between urban versus rural areas, and between coastal versus inland sites. We therefore caution that general patterns of wealth,wild meat consumption must be evaluated taking account the circumstances of wild meat consumers. [source] Global perspectives of contemporary epidemiological trends of cutaneous malignant melanomaBRITISH JOURNAL OF DERMATOLOGY, Issue 2 2004M.B. Lens Summary During the past several decades, there has been a substantial increase in the incidence of cutaneous melanoma among all caucasian populations. The number of deaths due to cutaneous malignant melanoma has also increased in most fair-skinned populations throughout the world in the past few decades. Trends in melanoma incidence worldwide are examined. The most recent data on the mortality from cutaneous melanoma are reported. The role of different environmental, genetic and host factors in the aetiology of melanoma is discussed. [source] | |||||||||||||