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Rationale Sex differences in the effects of cannabis have been demonstrated in animals, though the human evidence is more equivocal. In particular, more work is needed to better understand interactions between sex and dose in determining acute pharmacological effects of cannabis, especially at higher potencies of Δ 9 -tetrahydrocannabinol (THC). Objectives Sex differences were examined following a range of potencies of smoked...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Effects of 21 Years of Simulated Acidic Deposition on Tree Growth and Species Composition in an Aggrading Appalachian Hardwood ForestNARA Subscribed
The long-term effects of soil acidification on the development of a young aggrading Appalachian forest were examined after 21 years of continuous treatment. Beginning with a clearcut harvest in 1997, annual ammonium sulfate (N+S) and ammonium sulfate with lime (N+S+LIME) treatments were aerially applied to a developing forest. The lime treatment was designed to counteract the acidification of the nitrogen and sulfur amendments...
Nitrogen Availability Decreases the Severity of Snow Storm Damage in a Temperate ForestNARA Subscribed
Storms are among the greatest natural disturbances in temperate forests, and increased nitrogen (N) availability is thought to increase storm damage. However, the extent to which N availability increases damage from snowfall is less clear. To test how N availability might affect the susceptibility of trees to snow damage in a temperate forest, we took advantage of an opportunistic storm and surveyed damage in fertilized and un...
Investigating Evolutionary Rate Variation in BacteriaNARA Subscribed
Rates of molecular evolution are known to vary between species and across all kingdoms of life. Here, we explore variation in the rate at which bacteria accumulate mutations (accumulation rates) in their natural environments over short periods of time. We have compiled estimates of the accumulation rate for over 34 species of bacteria, the majority of which are pathogens evolving either within an individual host or during outb...
Nitrogen (N) additions have decreased species richness ( S ) in hardwood forest herbaceous layers, yet the functional mechanisms for these decreases have not been explicitly evaluated. We tested two hypothesized mechanisms, random species loss ( RSL ) and non‐random species loss ( NRSL ), in the hardwood forest herbaceous layer of a long‐term, plot‐scale, fertilization experiment in the central Appalachian Mountains, USA . Usi...
Modeled ecohydrological responses to climate change at seven small watersheds in the northeastern United StatesNARA Subscribed
A cross‐site analysis was conducted on seven diverse, forested watersheds in the northeastern United States to evaluate hydrological responses (evapotranspiration, soil moisture, seasonal and annual streamflow, and water stress) to projections of future climate. We used output from four atmosphere–ocean general circulation models ( AOGCM s; CCSM 4, Had GEM 2‐ CC , MIROC 5, and MRI ‐ CGCM 3) included in Phase 5 of the Coupled M...
Dominant species influence the composition and abundance of other species present in ecosystems. However, forecasts of distributional change under future climates have predominantly focused on changes in species distribution and ignored possible changes in spatial and temporal patterns of dominance. We develop forecasts of spatial changes for the distribution of species dominance, defined in terms of basal area, and for specie...
Incorporating spatial autocorrelation into species distribution models alters forecasts of climate‐mediated range shiftsNARA Subscribed
Species distribution models ( SDM s) are widely used to forecast changes in the spatial distributions of species and communities in response to climate change. However, spatial autocorrelation ( SA ) is rarely accounted for in these models, despite its ubiquity in broad‐scale ecological data. While spatial autocorrelation in model residuals is known to result in biased parameter estimates and the inflation of type I errors, th...
Hydroperiod is the main driver of the spatial pattern of dominance in mangrove communitiesNARA Subscribed
Aim Many mangrove communities form bands parallel to the shoreline with each community dominated by a single species. However, the key determinants of mangrove species distribution across the intertidal zone are not well understood. We aimed to quantify the relationship between species' dominance and the hydroperiod (defined as the duration of inundation in a year), soil salinity and the salinity of inundating water for three...