Alexandra Miller results 45
· Newest (Page 1/2, per page 25)
Author: Alexandra Miller ×Clear All Filters
Search Results
Polar Winter Processes: An Under-Represented Research Focus within the Coupled Earth SystemNARA Subscribed
Observing winter processes during the extended cold season is crucial not only for understanding polar and global coupled Earth system but also for enhancing capability of year-round prediction, especially in the context of Arctic amplification and the drastic decrease in sea ice extent and thickness at both poles. However, harsh environmental conditions and logistical challenges have left polar winter Earth system processes s...
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...
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...
Combined examination of mental workload and biomechanics during dual-task walking in individuals with lower-limb loss is limited to fixed, but not self-modulated walking pace, for which the latter enables dynamic cognitive-motor behavior as typically engaged during community ambulation. By assessing electroencephalography (EEG) (theta, low/high-alpha power) and biomechanics (gait speed, double limb support, stride width), the...
Linking Climate and Demography to Predict Population Dynamics and Persistence Under Global ChangeNARA Subscribed
Predicting the effects of climate change on plant and animal populations is an urgent challenge for understanding the fate of biodiversity under global change. At the surface, quantifying how climate drives the vital rates that underlie population dynamics appears simple, yet many decisions are required to connect climate to demographic data. Competing approaches have emerged in the literature with little consensus around best...
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...
Trace Mineral Source Influences Trace Mineral Solubility in Water and Mineral Binding Strength to Ruminal DigestaNARA Subscribed
Two experiments were conducted to examine the impact of trace mineral (TM) source on in vitro and in vivo solubility characteristics. Experiment 1: Hydroxy TM (HTM) and sulfate TM (STM) sources of Cu, Mn, and Zn were incubated separately in water for 24 h. Immediately after mixing, initial pH of each solution was greater (P < 0.03) for HTM compared to STM for all elements. Final pH tended to be greater for Cu (P = 0.09) and Zn...
A Busse Balloon in the Lagoon: Herbivore Behaviour Generates Spatial Patterns in Coral Reef EcosystemsNARA Subscribed
Spatial processes, particularly scale‐dependent feedbacks, may play important and underappreciated roles in the dynamics of bistable ecosystems. For example, self‐organised spatial patterns can allow for stable coexistence of alternative states outside regions of bistability, a phenomenon known as a Busse balloon. We used partial differential equations to explore the potential for such dynamics in coral reefs, focusing on how...
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...
Best practices for collecting and preserving marine mammal biological samples in the ‘omics eraNARA Subscribed
The recent rise of ‘omics and other molecular research technologies alongside improved techniques for tissue preservation have broadened the scope of marine mammal research. Collecting biological samples from wild marine mammals is both logistically challenging and expensive. To enhance the power of marine mammal research, great effort has been made in both the field and the laboratory to ensure the scientific integrity of sam...
Monitoring is a crucial tool for measuring the progress and success of environmental policies and management programs. While many studies have evaluated the effectiveness of biodiversity sampling methods, few have compared their efficiency, which is crucial given the funding constraints present in all conservation efforts. In this study we demonstrate how existing analytical tools can be applied to (i) assess the relationship...