For organisms in seasonal environments, individuals that breed earlier in the season regularly attain higher fitness than their late-breeding counterparts. Two primary hypotheses have been proposed to explain these patterns: The quality hypothesis contends that early breeders are of better phenotypic quality or breed on higher quality territories, whereas the date hypothesis predicts that seaso...

Seasonal declines of fitness-related traits are often attributed to environmental effects or individual-level decisions about reproductive timing and effort, but genetic variation may also play a role. In populations of Pacific salmon (Oncorhynchus spp.), seasonal declines in reproductive life span have been attributed to adaptation-by-time, in which divergent selection for different traits occ...

Pesticide safety training is mandated for migrant and seasonal farmworkers. However, none is required for family members, who implement home sanitation to protect against pesticide exposure and need to control pests in substandard housing. Controlled studies have demonstrated the efficacy of pesticide education programs for farmworker families, but no carefully evaluated demonstration projects ...

BACKGROUND Current asthma management guidelines are based on the level of asthma control. The impact of asthma control on health care resources and quality of life (QoL) is insufficiently studied. EUCOAST study was designed to describe costs and QoL in adult patients according to level of asthma control in France and Spain. METHODS An observational cost of illness study was conducted simultan...

We assumed that the cross-protective immunity acquired through natural infection declines gradually in the absence of re-exposure to similar strains or vaccination [1]. We considered this decline in the model, and assumed that the pre-existing immunity (resulted from natural infection) becomes ineffective after m1 seasons (due to continual viral drift). Consistent with the observed data, we con...

The evidence presented indicates that cabbage maturing in the spring and summer months has little goiter-produdag power. Cabbage maturing in the late autumn has much greater goiter-produdng power, although this shows considerable variation in different years. It has not been possible to correlate available meteorological data with these variations.

Partial migration, in which a fraction of a population migrate and the rest remain resident, occurs in an extensive range of species and can have powerful ecological consequences. The question of what drives differences in individual migratory tendency is a contentious one. It has been shown that the timing of partial migration is based upon a trade-off between seasonal fluctuations in predatio...

The impact of a nonlinear dynamic cellular automaton (CA) model, as a representation of the partially stochastic aspects of unresolved scales in global climate models, is studied in the European Centre for Medium Range Weather Forecasts coupled ocean-atmosphere model. Two separate aspects are discussed: impact on the systematic error of the model, and impact on the skill of seasonal forecasts. ...

BACKGROUND Light severely affects the occurrence of seasonal affective disorder (SAD). AIMS To compare the prevalence of SAD in persons with severe visual impairment and persons with full sight, and in persons with severe visual impairment with or without light perception. METHOD This cross-sectional study assessed the Global Seasonality Score (GSS) and the prevalence of SAD among 2781 pers...

BACKGROUND Much research has been devoted to the determination of optimal vaccination strategies for seasonal influenza epidemics. However, less attention has been paid to whether this optimization can be achieved within the context of viral drift. METHODS We developed a mathematical model that links different intra-seasonal dynamics of vaccination and infection to investigate the effect of v...