The purpose of this review was to examine seasonal variation in physical activity among children and adolescents. Searches were conducted of electronic databases for studies on seasonal differences in physical activity levels. A total of 35 studies, including children and adolescents between the ages of 2-19 years, were reviewed. Overall, 83% (29/35) of the studies found seasonal variation in p...

Objective Although the daily urinary sodium excretion (UNaV) is considered to provide the most reliable estimate of the daily sodium intake, it may be affected by salt loss due to sweating in summer. However, the seasonal variation in the daily UNaV associated with a normal lifestyle is unknown. Methods This study was performed in 348 outpatients from the Morioka region during three seasons: su...

San Francisco Bay is contaminated by mercury (Hg) due to historic and ongoing sources, and has elevated Hg concentrations throughout the aquatic food web. We monitored Hg in forage fish to indicate seasonal and interannual variations and trends. Interannual variation and long-term trends were determined by monitoring Hg bioaccumulation during September-November, for topsmelt (Atherinops affinis...

Environmental conditions experienced in early life affect growth and influence life history strategies, especially in seasonal environments. We studied the seasonal and sexual variation in resource allocation in juvenile southern elephant seals to investigate whether they show a seasonal decline in growth. We also examined whether sexual differences in growth may lead to separate growth strateg...

No large study has described the seasonal variation in asthma attacks in population-based asthmatics in whom sensitisation to allergen has been measured. 2,637 young adults with asthma living in 15 countries reported the months in which they usually had attacks of asthma and had skin-prick tests performed. Differences in seasonal patterns by sensitisation status were assessed using generalised ...

Background: Reproductive strategies and evolutionary pressures differ between males and females. This often results in size differences between the sexes, and also in sex-specific seasonal variation in body mass. Seasonal variation in body mass is also affected by other factors, such as weather. Studies on sex-specific body mass patterns may contribute to better understand the mating system of ...

BACKGROUND There are seasonal variations and gender differences in incidence of type 1 diabetes (T1D), metabolic control and responses to immune interventions at onset of the disease. We hypothesized that there are seasonal and gender differences in residual insulin secretion already at diagnosis of T1D. METHODS In 2005, a national study, the Better Diabetes Diagnosis, was started to classify...

The blue mussel, Mytilus edulis, attaches itself to the substrate by producing a radially arranged complex of collagenous byssal threads. The strength of byssal attachment, or tenacity, has been shown to vary seasonally on Rhode Island shores, increasing twofold in spring in comparison with fall. It was previously assumed that this seasonality was due to increased thread production following pe...

Seasonal timing of life-history events is often under strong natural selection. The Clock gene is a central component of an endogenous circadian clock that senses changes in photoperiod (day length) and mediates seasonal behaviours. Among Pacific salmonids (Oncorhynchus spp.), seasonal timing of migration and breeding is influenced by photoperiod. To expand a study of 42 North American Chinook ...

OBJECTIVES/HYPOTHESIS To examine the incidence of epistaxis as a function of season and age and to determine predictors of episodes within the epistaxis patient population presenting to a tertiary hospital system. STUDY DESIGN Retrospective cohort study. METHODS Electronic medical record charts of patients presenting to the Northwestern Emergency Department, admitted to an inpatient ward, o...