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The “Too-Few Elephant Problem”: Quantitative Analysis of Historical Elephant Tree-Toppling Rates Across AfricaNARA Subscribed
Elephants were a major driver of tree stem mortality in Africa, but their impacts are now spatially constrained and they no longer topple trees across the continent. Thus, most African landscapes lack a key ecological agent that helped maintain diversity and functioning. Even ecologists living in Africa fail to anticipate the rampant destruction of trees that can occur when elephants live in and move through landscapes. If we...
An experimental approach to assess the combined effects of multiple stressors on a large vertebrate speciesNARA Subscribed
The design of experiments to investigate the combined effects of multiple stressors requires exposing target organisms to multiple combinations of stressor doses. Concurrent manipulation of stressors is often infeasible with wildlife, but long‐lasting health effects allow individual health to be used as an integrator of prior stressor exposure. The population of bottlenose dolphins in Barataria Bay, Louisiana, experienced long...
Dryland ecosystems cover 41% of Earth's land surfaces, account for 44% of cultivated lands and 60% of food sources, and make large contributions to the global water and carbon cycles. However, these ecosystems are experiencing unprecedented extremes including heatwaves, floods, and droughts as well as hotter temperatures and often declining water resource availability. These ecosystems are some of the most challenging to monit...
Global patterns and regional insights into kelp forest protection, restoration, and stewardshipNARA Subscribed
Kelp forests are among the most extensive and productive coastal ecosystems, yet they remain underrepresented in global conservation policy despite widespread declines driven by interacting global- (i.e., ocean warming, marine heatwaves) to local-scale stressors. At the same time, kelp conservation and restoration efforts are expanding rapidly across regions, but measures of success and syntheses tend to primarily focus on eco...
Comparison of Six Data Cleaning Methods for Determining Repetitive Head Impact Exposure in Youth Tackle FootballNARA Subscribed
Purpose Instrumented mouthguards (iMGs) are commonly used to quantify head acceleration event (HAE) exposure, but accurate interpretation requires rigorous data cleaning methods. This study compared six data cleaning methods for determining HAE rates and magnitudes, as well as cleaning method validity compared to the 5 th method video verification in youth tackle football. Methods Fifty athletes (ages 8-12) wore Impact Monitor...
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...
Alzheimer’s disease (AD) disproportionately affects women and carriers of the apolipoprotein E ε4 allele (APOE4), yet little is known about how sex and APOE interact to influence white matter (WM) integrity during disease progression. We integrated diffusion MRI and matched blood transcriptomic data to investigate these interactions and their underlying biological mechanisms. WM microstructure was quantified using diffusion te...
The impediments to sediment characterization: describing sediments from urban surfacesNARA Subscribed
Purpose Sediment generated from urban surfaces is transported via stormwater runoff, posing significant threats to the environment and infrastructure. Sediment laden runoff, often transporting pollutants, can be highly taxing to downstream waters, both receiving stormwater treatment facilities and natural bodies of surface water. However, the characterization of urban sediments are poorly understood, making it impossible to fu...
Conservation genomics of the imperiled Leon springs pupfish, Cyprinodon bovinus, across temporal and spatial scalesNARA Subscribed
The Leon Springs pupfish, Cyprinodon bovinus , is federally listed as endangered and currently confined to spring-fed pools on the Diamond Y Spring Preserve in Pecos County, Texas, USA. A refuge population is maintained by U.S. Fish and Wildlife Service in Dexter, New Mexico, USA because of ongoing threats from hybridization with the introduced congener, the sheepshead minnow, C. variegatus. To inform continued conservation an...