Firefighting is strenuous work that results in considerable cardiovascular strain. Sudden cardiac events are the leading cause of duty-related death in the fire service. This cross-sectional study examined cardiometabolic measures and prevalence of risk factors in firefighters by age and sex and compare these data to the general population. Data obtained at medical exams (2015-2018) from 4279 male and 234 female career firefighters at four occupational health clinics in the United States were analyzed. Estimates for the general population were obtained using the 2015-16 National Health and Nutrition Examination Survey fasting subsample. Linear regression models stratified by sex with age modelled as a continuous variable were used to examine general trends. Point estimates across age groups (20-29, 30-39, 40-49, and 50-59 year olds) for cardiometabolic measures were reported. Among the total sample, 36% were obese and 25% had low HDL cholesterol. Females had significantly lower body mass index (BMI), LDL cholesterol, triglycerides and blood glucose than males. A significant quadratic relationship of age with BMI, total cholesterol, LDL cholesterol, and triglycerides was found in males with increasing values peaking between 45 and 50 years. Total cholesterol and LDL cholesterol increased with age among females. Blood glucose increased with age in both sexes. Firefighters had similar or better cardiometabolic health profiles than the US general population; however, both samples had a concerning prevalence of cardiometabolic risk factors among individuals ≥ 40 years of age. Health professionals and fire service members alike should consider prevention efforts among young firefighters and better treatment among older firefighters.
This study expands traditional reaction-diffusion models by incorporating hyperbolic dynamics to explore the effects of inertial delays on pattern formation. The kinetic system considers a harvested predator-prey model where predator and prey populations gather in herds. Diffusion and inertial effects are subsequently introduced.
Background: Iron deficiency anaemia (IDA) related to occult gastrointestinal tract (GIT) blood loss is associated with high rates of GIT malignancies. Major society guidelines recommend bidirectional endoscopic evaluation for all men and post-menopausal women with newly diagnosed, unexplained IDA. However, in patients prescribed direct oral anticoagulants (DOACs), the endoscopic yield, specifically the rate of high-risk findings, including colorectal cancers (CRCs) and advanced adenomas (AAs), is unknown.
AbstractLarge-scale temporal and spatial biodiversity patterns have traditionally been explained by multitudinous particular factors and a few theories. However, these theories lack sufficient generality and do not address fundamental interrelationships and coupled dynamics among resource availability, community abundance, and species richness. We propose the equilibrium theory of biodiversity dynamics (ETBD) to address these linkages.
AbstractInducible defenses can affect the persistence, structure, and stability of consumer-resource systems. Theory shows that these effects depend on characteristics of the inducible defense, including timing, costs, efficacy, and sensitivity to consumer density. However, the expression and costs of inducible defenses often vary among life stages, which has not been captured in previous unstructured models.
AbstractTheoretical studies from diverse areas of population biology have shown that demographic stochasticity can substantially impact evolutionary dynamics in finite populations, including scenarios where traits that are disfavored by natural selection can nevertheless increase in frequency through the course of evolution. Here, we analytically describe the eco-evolutionary dynamics of finite populations from demographic first principles. We investigate how noise-induced effects can alter the evolutionary fate of populations in which total population size may vary stochastically over time.
