Christopher Ellis results 67
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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...
Assessing the impact of climate change on verticillium wilt and the implications for cotton production in AustraliaNARA Subscribed
Climate change poses significant challenges for agricultural production, potentially altering crop distribution, productivity, and the prevalence of plant diseases. This study focuses on the fungus Verticillium dahliae which causes disease in over 400 plant species, significantly impacting cotton in most major cotton producing countries. We investigate how climate suitability for V. dahliae could change in the future, using Ne...
Bonefish Albula spp. in the Western Atlantic have historically been morphometrically and phenotypically indiscernible. We used biofluorescence in two sympatric, cryptic bonefish species, Albula goreensis and Albula vulpes , to develop a rapid and inexpensive in situ survey for species identification that can be used by managers and recreational anglers. Under ultraviolet (379–387 nm) and royal blue (440–457 nm) lights, the two...
Species nativeness as a cultural paradigm in conservationNARA Subscribed
Predicting the progression of MCI and Alzheimer’s disease on structural brain integrity and other features with machine learningNARA Subscribed
Machine learning (ML) on structural MRI data shows high potential for classifying Alzheimer’s disease (AD) progression, but the specific contribution of brain regions, demographics, and proteinopathy remains unclear. Using Alzheimer’s Disease Neuroimaging Initiative (ADNI) data, we applied an extreme gradient-boosting algorithm and SHAP (SHapley Additive exPlanations) values to classify cognitively normal (CN) older adults, th...
The trade-off between photosynthetic rate and thallus moisture-demand explains lichen habitat association with the temperate rainforestNARA Subscribed
Temperate rainforests are globally rare, covering less than 1% of the Earth’s surface, with 15% of their suitable climate space located in Europe. These ecosystems are uniquely defined by diverse cryptogamic species, particularly epiphytic lichens, which play crucial roles in forest biodiversity, trophic interactions, and biogeochemical processes. However, the ecophysiology of temperate rainforest lichens, with the potential t...
SNAPSHOT USA 2019–2023: The First Five Years of Data From a Coordinated Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multicontributor 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 specie...
Numerical simulation of sediment transport and subsequent morphological evolution rely on accurate parameterizations of sediment characteristics. However, these data are often not available or are spatially and/or temporally limited. This study approaches the problem of limited sediment grain-size data with a series of simulations assessing model sensitivity to sediment parameters and initial bed composition configurations in...
Heavy-metal associated breast cancer and colorectal cancer hot spots and their demographic and socioeconomic characteristicsNARA Subscribed
Purpose Cancer registries offer an avenue to identify cancer clusters across large populations and efficiently examine potential environmental harms affecting cancer. The role of known metal carcinogens (i.e., cadmium, arsenic, nickel, chromium(VI)) in breast and colorectal carcinogenesis is largely unknown. Historically marginalized communities are disproportionately exposed to metals, which could explain cancer disparities....
SNAPSHOT USA 2021: A third coordinated national camera trap survey of the U nited S tatesNARA Subscribed
SNAPSHOT USA is a multicontributor, long‐term camera trap survey designed to survey mammals across the United States. Participants are recruited through community networks and directly through a website application ( https://www.snapshot-usa.org/ ). The growing Snapshot dataset is useful, for example, for tracking wildlife population responses to land use, land cover, and climate changes across spatial and temporal scales. Her...
Identifying and Constraining Marsh-Type Transitions in Response to Increasing Erosion over the Past CenturyNARA Subscribed
Marsh environments, characterized by their flora and fauna, change laterally in response to shoreline erosion, water levels and inundation, and anthropogenic activities. The Grand Bay coastal system (USA) has undergone multiple large-scale geomorphic and hydrologic changes resulting in altered sediment supply, depositional patterns, and degraded barrier islands, leaving wetland salt marshes vulnerable to increased wave activit...
The lack of data on the age, growth, and reproduction of the Atlantic Goliath Grouper Epinephelus itajara off the coasts of Florida (USA) makes it difficult to estimate the extent of their population recovery following the 1990 fishery closure, as well as the potential effects of the recent (2023) opening of a fishery for juveniles. Goliath Grouper from the Atlantic coast of Florida were non-lethally sampled for size (total le...
Atlantic goliath grouper (Epinephelus itajara), the largest reef fish in the Western Atlantic, exhibit high site fidelity to home reefs but also undertake annual migrations to distant spawning sites. Once relatively common throughout Florida and the Caribbean, the species; is now considered vulnerable (i.e., threatened with extinction) due to overfishing and loss of juvenile mangrove habitat. Goliath grouper in the southeaster...
Climate change is altering species’ range limits and transforming ecosystems. For example, warming temperatures are leading to the range expansion of tropical, cold-sensitive species at the expense of their cold-tolerant counterparts. In some temperate and subtropical coastal wetlands, warming winters are enabling mangrove forest encroachment into salt marsh, which is a major regime shift that has significant ecological and so...