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In Situ Evidence for Quantitative Nitrogen Fixation in a Temperate Perennial Grass EcosystemNARA Subscribed
Biological nitrogen (N) fixation is an important terrestrial ecosystem N input that occurs in both symbiotic and non-symbiotic associations with plants. Non-symbiotic nitrogen fixation (NSNF) has been documented in many places, including soils, but the magnitude of its inputs, along with drivers of NSNF rates, remains uncertain due to methodological challenges. We measured NSNF by applying a 15 N 2 tracer to field mesocosms th...
Mating systems shape the population dynamics of species, influencing attributes such as effective population size and population persistence. Traditionally, genetic analysis of mating systems includes the genotyping of putative parents to determine parentage. However, for cryptic or migratory species, and those with large populations, comprehensive sampling of adults is often not feasible. One underutilised alternative is to r...
Marine climate variability and change in the Torres StraitNARA Subscribed
Marine Isotope Stage 4 glaciation in northern England, UK: Evidence from Victoria Cave, North YorkshireNARA Subscribed
Victoria Cave, north Yorkshire, England, contains a long sequence of Pleistocene clastic sediments and calcite flowstones. Earlier work, using U–Th dating, established that the flowstone units formed in interglacial stages corresponding to Marine Isotope Stages (MIS) 13, 11, 9, 7 and 5. The intervening laminated sediments were therefore assigned to glacial stages (MIS 12, 10, 6 and 2) and regarded as rhythmites that settled fr...
Bottom‐tow gear fisheries (trawls and dredges) produce ~24 million mt of harvest annually, representing a globally important animal‐sourced food system. While many are currently sustainably managed, growing concern over the potential for ecosystem impacts from bottom‐tow gears has increased pressure to improve these fisheries. We assembled an international working group of > 30 contributors, including fishing industry particip...
The Integration of Fire Ecology and Freshwater Ecosystems in North America: Knowledge Gaps and Research NeedsNARA Subscribed
Wildfires, unplanned fires that start and spread under the influence of weather and fuel composition, are increasing in frequency, duration, and severity across North America. While wildfires are one component of wildland fire, a broader natural process in many ecosystems, their changing behavior poses growing ecological and management challenges. Although wildfire is widely recognized as an important disturbance, empirical re...
Late presentation of ovarian cancer continues to pose a major challenge, as the disease typically manifests with vague and misattributed symptoms. Public awareness initiatives have sought to address this through the use of succinct, symptom-based messaging. The BEAT acronym – Bloating, Eating difficulties, Abdominal pain, Toilet changes – has been developed as a public health tool to promote symptom recognition and timely acti...
Capelin ( Mallotus spp.) are pelagic forage fishes that can be especially abundant in sub‐arctic marine ecosystems and are important prey for upper trophic‐level consumers. Abundance and distribution of capelin have been linked to ocean temperature, but the magnitude and directionality of thermal sensitivity can vary regionally. We used data spanning two decades (2002–2022) from autumn surface trawl surveys in three Alaska lar...
Seasonal differences in predation risk among seagrass epifauna species stabilize community‐level predation over timeNARA Subscribed
Predation risk varies through space and time due to changing refuge quality, predator communities, and prey traits. Despite this, ecological research is often focused on measuring average predation risk at the community level. While this can give important information about overall trophic transfer and ecological efficiency, it ignores differences in predation risk among prey species within a community, which may be important...
Diversity and functional group composition drive biogeographic patterns in marine biogenic structural complexityNARA Subscribed
Biogenic structural complexity is a key driver of biodiversity and ecosystem functioning, yet its ecological and environmental determinants remain poorly understood across broad biogeographic scales. Here, we conducted standardized 90‐day field experiments at 16 coastal sites, spanning a 41‐degree latitudinal gradient, using naturally assembled marine fouling communities on settlement panels. We measured rugosity as our metric...
Interpretable deep learning reveals spatiotemporal MRI features of brain aging that align with neurodegenerationNARA Subscribed
Cortical thinning and atrophy are hallmarks of brain aging that have been characterized using magnetic resonance imaging (MRI). Brain aging involves many neuroanatomic features whose effects on brain structure remain unexplored. To address this challenge, we trained interpretable deep neural networks (DNNs) to estimate brain age (BA) from T 1 -weighted ( T 1 w) MRI. By identifying MRI features unapparent to humans, DNNs can fi...
SNAPSHOT USA 2024: Year 6 of the Coordinated National Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multi‐contributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of speci...