Search results for "POPULATION"
showing 10 items of 9945 documents
Genetic structure in the paleoendemic and endangered Petagnaea gussonei (Spreng.) Rauschert (Saniculoideae, Apiaceae) and implications for its conser…
2012
Our investigation aims to understand the genetic structure and evolutionary history of Petagnaea gussonei, an ancient and endangered species belonging to the Saniculoideae subfamily (Apiaceae). It is paleoendemic to Sicily, with a small number of populations in the Nebrodi Mountains. A total of seven chloroplast microsatellite repeat loci and 12 AFLP primer combinations were used to screen 115 individuals corresponding to 17 populations. The ratio of seed to pollen flow was also calculated using the modified Ennos equation. A relatively high level of genetic diversity was detected with AFLPs (e.g., 0.045 < H < 0.278), and a moderate variation was also found using cpSSRs (0 < Hk < 0.667). Tw…
Magnitude, temporal trends, and projections of the global prevalence of blindness and distance and near vision impairment: a systematic review and me…
2017
PubMed: 28779882
Global diversity in the TAS2R38 bitter taste receptor: revisiting a classic evolutionary PROPosal
2016
AbstractThe ability to taste phenylthiocarbamide (PTC) and 6-n-propylthiouracil (PROP) is a polymorphic trait mediated by the TAS2R38 bitter taste receptor gene. It has long been hypothesized that global genetic diversity at this locus evolved under pervasive pressures from balancing natural selection. However, recent high-resolution population genetic studies of TAS2Rs suggest that demographic events have played a critical role in the evolution of these genes. We here utilized the largest TAS2R38 database yet analyzed, consisting of 5,589 individuals from 105 populations, to examine natural selection, haplotype frequencies and linkage disequilibrium to estimate the effects of both selectio…
Epidemiology of congenital diaphragmatic hernia in Europe: a register-based study.
2015
INTRODUCTION: Published prevalence rates of congenital diaphragmatic hernia (CDH) vary. This study aims to describe the epidemiology of CDH using data from high-quality, population-based registers belonging to the European Surveillance of Congenital Anomalies (EUROCAT).METHODS: Cases of CDH delivered between 1980 and 2009 notified to 31 EUROCAT registers formed the population-based case series. Prevalence over time was estimated using multilevel Poisson regression, and heterogeneity between registers was evaluated from the random component of the intercept.RESULTS: There were 3373 CDH cases reported among 12 155 491 registered births. Of 3131 singleton cases, 353 (10.4%) were associated wit…
Anorectal malformations and pregnancy-related disorders: a registry-based case-control study in 17 European regions
2013
Objective To identify pregnancy-related risk factors for different manifestations of congenital anorectal malformations (ARMs).Design A population-based case-control study.Setting Seventeen EUROCAT (European Surveillance of Congenital Anomalies) registries, 1980-2008.Population The study population consisted of 1417 cases with ARM, including 648 cases of isolated ARM, 601 cases of ARM with additional congenital anomalies, and 168 cases of ARM-VACTERL (vertebral, anal, cardiac, tracheo-esophageal, renal, and limb defects), along with 13371 controls with recognised syndromes or chromosomal abnormalities.Methods Multiple logistic regression analyses were used to calculate adjusted odds ratios …
Epidemiology of eating disorders in Latin America: a systematic review and meta-analysis.
2016
Purpose of reviewEating disorders are currently not considered to be limited to Western culture. We systematically reviewed the existing literature on the prevalence of eating disorders in Latin America.Recent findingsOf 1583 records screened, 17 studies from Argentina, Brazil, Chile, Colombia, Mexico, and Venezuela were included in the analysis. Most studies reported point-prevalence rates and only three studies provided lifetime and 12-month prevalence rates. We found a mean point-prevalence rate of 0.1% for anorexia nervosa, 1.16% for bulimia nervosa, and 3.53% for binge-eating disorder (BED) in the general population. Heterogeneity for bulimia nervosa and BED was large. This meta-analys…
Flexibility in otherwise consistent non-breeding movements of a long-distance migratory seabird, the long-tailed skua
2017
Quantifying within- and between-individual variation in animal migration strategies is a first step towards our understanding of the ability of migrants to adjust to changes in the en - vironment. We studied consistency (or, conversely, flexibility) in movement patterns at large (>1000 km) to meso-scales (100−1000 km) during the non-breeding season of the long-tailed skua Stercorarius longicaudus, a long-distance migratory Arctic seabird, using light-based geolocation. We obtained 97 annual tracks of 38 individuals and quantified similarity between routes. Overall, tracks of the same individual were generally within about 200 to 300 km of their previous year’s route, and more similar than t…
Combined metabolic activity within an atrazine-mineralizing community enriched from agrochemical factory soil
2007
Abstract The main objective of this work was to characterize an atrazine-mineralizing community originating from agrochemical factory soil, especially to elucidate the catabolic pathway and individual metabolic and genetic potentials of culturable members. A stable four-member bacterial community, characterized by colony morphology and 16S rDNA sequencing, was rapidly able to mineralize atrazine to CO 2 and NH 3 . Two primary organisms were identified as Arthrobacter species (ATZ1 and ATZ2) and two secondary organisms (CA1 and CA2) belonged to the genera Ochrobactrum and Pseudomonas, respectively. PCR assessment of atrazine-degrading genetic potential of the community, revealed the presence…
Additional insights on the ecology of the relic tree Zelkova sicula di Pasquale, Garfì et Quézel (Ulmaceae) after the finding of a new population
2011
Abstract In early autumn 2009 a new population of Zelkova sicula, a very threatened tree species endemic to Sicily, has been found some 17 km east from the first and unique population previously known. The abiotic (slope, rock and stone outcrop cover, environmental stress, etc.) and biotic (plant species composition, vegetation mean height, total cover, etc.) features of 30 plots selected within the two populations were investigated in order to contribute at clarifying the actual and potential eco-geographic range of this species. Data analysis showed that the floristic differences among the sampled plots mostly relate to the rather high micro-habitat amplitude of the target species and the…
Modelling temperature-dependent dynamics of single and mixed infections in a plant virus
2022
Multiple viral infection is an important issue in health and agriculture with strong impacts on society and the economy. Several investigations have dealt with the population dynamics of viruses with different dynamic properties, focusing on strain competition during multiple infections and the effects on viruses’ hosts. Recent interest has been on how multiple infections respond to abiotic factors such as temperature (T). This is especially important in the case of plant pathogens, whose dynamics could be affected significantly by global warming. However, few mathematical models incorporate the effect of T on parasite fitness, especially in mixed infections. Here, we investigate simple mat…