Samuel Allen results 36
· Newest (Page 1/2, per page 25)
Author: Samuel Allen ×Clear All Filters
Search Results
Motivation Here, we make available a second version of the BioTIME database, which compiles records of abundance estimates for species in sample events of ecological assemblages through time. The updated version expands version 1.0 of the database by doubling the number of studies and includes substantial additional curation to the taxonomic accuracy of the records, as well as the metadata. Moreover, we now provide an R packag...
Sustaining Productivity while Reducing Methane Emission in Calcareous Soils: Implications of Combining Inorganic Fertilizer and BiocharNARA Subscribed
A considerable proportion of applied nutrients are adsorbed by the calcite surface of calcareous soils, making them unavailable to plants. A combination of organic amendments and fertilizers can improve nutrient retention and mineralization, and also reduce greenhouse gas (GHG) emissions. A two-years field experiment was undertaken to investigate the impacts of inorganic fertilizer, biochar and silicon on nutrient uptake, grow...
Demographic History and Adaptive Evolution of Indo‐Pacific Bottlenose Dolphins ( Tursiops aduncus ) in Western AustraliaNARA Subscribed
Demographic processes can substantially affect a species' response to changing ecological conditions, necessitating the combined consideration of genetic responses to environmental variables and neutral genetic variation. Using a seascape genomics approach combined with population demographic modelling, we explored the interplay of demographic and environmental factors that shaped the current population structure in Indo‐Pacif...
Targeting mitochondria in the aged cerebral vasculature with SS-31, a proteomic study of brain microvesselsNARA Subscribed
Cognitive impairment and dementias during aging such as Alzheimer’s disease are linked to functional decline and structural alterations of the brain microvasculature. Although mechanisms leading to microvascular changes during aging are not clear, loss of mitochondria, and reduced efficiency of remaining mitochondria appear to play a major role. Pharmacological agents, such as SS-31, which target mitochondria have been shown t...
Reconstructing the colonization history of Indo‐Pacific bottlenose dolphins ( Tursiops aduncus ) in Northwestern AustraliaNARA Subscribed
Bottlenose dolphins ( Tursiops spp.) are found in waters around Australia, with T. truncatus typically occupying deeper, more oceanic habitat, while T. aduncus occur in shallower, coastal waters. Little is known about the colonization history of T. aduncus along the Western Australian coastline; however, it has been hypothesized that extant populations are the result of an expansion along the coastline originating from a sourc...
Introduced predators can have harmful top‐down effects on their newly colonized system through competition with and direct predation on native species. Following an initial introduction of muskellunge in Lac Frontière, Québec in the 1970s at the headwaters of the Wolastoq/Saint John River, the species rapidly migrated downstream, expanding its range by ~500 km over ~20 years. Despite this expansive colonization and concern ove...
SNAPSHOT USA 2020: A second coordinated national camera trap survey of the United States during the COVID ‐19 pandemicNARA Subscribed
Managing wildlife populations in the face of global change requires regular data on the abundance and distribution of wild animals, but acquiring these over appropriate spatial scales in a sustainable way has proven challenging. Here we present the data from Snapshot USA 2020, a second annual national mammal survey of the USA. This project involved 152 scientists setting camera traps in a standardized protocol at 1485 location...
Association patterns and community structure among female bottlenose dolphins: environmental, genetic and cultural factorsNARA Subscribed
Social structuring from assortative associations may affect individual fitness, as well as population-level processes. Gaining a broader understanding of social structure can improve our knowledge of social evolution and inform wildlife conservation. We investigated association patterns and community structure of female Indo-Pacific bottlenose dolphins ( Tursiops aduncus ) in Shark Bay, Western Australia, assessing the role of...
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...
CpG-creating mutations are costly in many human virusesNARA Subscribed
Mutations can occur throughout the virus genome and may be beneficial, neutral or deleterious. We are interested in mutations that yield a C next to a G, producing CpG sites. CpG sites are rare in eukaryotic and viral genomes. For the eukaryotes, it is thought that CpG sites are rare because they are prone to mutation when methylated. In viruses, we know less about why CpG sites are rare. A previous study in HIV suggested that...
Effort rights‐based managementNARA Subscribed
Effort rights‐based fisheries management ( RBM ) is less widely used than catch rights, whether for groups or individuals. Because RBM on catch or effort necessarily requires a total allowable catch ( TAC ) or total allowable effort ( TAE ), RBM is discussed in conjunction with issues in assessing fish populations and providing TAC s or TAE s. Both approaches have advantages and disadvantages, and there are trade‐offs between...
Temporal variability in aboveground plant biomass decreases as spatial variability increasesNARA Subscribed
Ecological theory predicts that diversity decreases variability in ecosystem function. We predict that, at the landscape scale, spatial variability created by a mosaic of contrasting patches that differ in time since disturbance will decrease temporal variability in aboveground plant biomass. Using data from a multi‐year study of seven grazed tallgrass prairie landscapes, each experimentally managed for one to eight patches, w...