Population dynamics, life stage and ecological modeling in Chrysomya albiceps (Wiedemann) (Diptera: Calliphoridae)

In this study we investigated the population dynamics of Chrysomya albiceps (Wiedemann) with laboratory experiments, employing survival analysis and stage structure mathematical models, emphasizing survival among life stages. The study also assessed the theoretical influence of density dependence and cannibalism during immature stages, on the population dynamics of the species. The survival curves were similar, indicating that populations of C. albiceps exhibit the same pattern of survival among life stages. A strong nonlinear trend was observed, suggesting density dependence, acting during the first life stages of C. albiceps. The time-series simulations produced chaotic oscillations for all life stages, and the cannibalism did not produce qualitative changes in the dynamic behavior. The bifurcation analysis shows that for low values for survival, the population reaches a stable equilibrium, but the cannibalism results in chaotic oscillations practically over all the parametric space. The implications of the patterns of dynamic behavior observed are discussed.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)WACGCNPqFAPES

Salmonella Strains Isolated from Galápagos Iguanas Show Spatial Structuring of Serovar and Genomic Diversity

It is thought that dispersal limitation primarily structures host-associated bacterial populations because host distributions inherently limit transmission opportunities. However, enteric bacteria may disperse great distances during food-borne outbreaks. It is unclear if such rapid long-distance dispersal events happen regularly in natural systems or if these events represent an anthropogenic exception. We characterized Salmonella enterica isolates from the feces of free-living Galápagos land and marine iguanas from five sites on four islands using serotyping and genomic fingerprinting. Each site hosted unique and nearly exclusive serovar assemblages. Genomic fingerprint analysis offered a more complex model of S. enterica biogeography, with evidence of both unique strain pools and of spatial population structuring along a geographic gradient. These findings suggest that even relatively generalist enteric bacteria may be strongly dispersal limited in a natural system with strong barriers, such as oceanic divides. Yet, these differing results seen on two typing methods also suggests that genomic variation is less dispersal limited, allowing for different ecological processes to shape biogeographical patterns of the core and flexible portions of this bacterial species' genome

Tinnitus annoyance assessed by the Tinnitus Handicap Inventory

OBJECTIVE: The Tinnitus Handicap Inventory is a questionnaire for assessing the impact of tinnitus by quantifying psychoemotional and functional problems it causes. The objective of the study was to validate the Brazilian Portuguese translation of this questionnaire, named Questionario de Gravidade do Zumbido. METHODS: The questionnaire was applied to 135 individuals with tinnitus from two audiology clinics in Bauru, Southeastern Brazil, referred for audiologic evaluation. Its internal consistency was evaluated by Cronbach's alpha coefficients comparing the Brazilian version to the original instrument. RESULTS: It was found good reliability for scales (0.76 <alpha < 0.85) and for the whole questionnaire, which global consistency value (alpha=0.93) was identical to the original instrument. CONCLUSIONS: The results suggest that the Brazilian version of the questionnaire can be used in clinical practice to evaluate day-to-day difficulties caused by tinnitus in individuals who are aware of that.40470671