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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...
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...
Barracuda: a dynamic, Turing-complete GPU virtual machine for high-performance simulationsNARA Subscribed
Accurate simulation of dynamic biological phenomena, such as tissue response and disease progression, is crucial in biomedical research and diagnostics. Traditional GPU-based simulation frameworks, typically static CUDA ® environments, struggle with dynamically evolving parameters, limiting flexibility and clinical applicability. We introduce Barracuda, an open-source, lightweight, header-only, Turing-complete virtual machine...
Cross‐Continental Analysis Shows That Disturbance Effects on Reptile Body Condition Do Not Predict Abundance ResponsesNARA Subscribed
Ecological disturbances are discrete events that alter or transform the physical, chemical, or biological characteristics of ecosystems. Disturbance can cause animal populations to decline and, according to the risk‐disturbance hypothesis and population collapse framework, these declines can be predicted by declines in animal body condition. However, no research has empirically examined the general relationship between body co...
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...
Rising temperatures favour defence-suppressing herbivoresNARA Subscribed
Rising temperatures due to climate change are predicted to accelerate the life cycle of arthropod herbivores thereby exacerbating pest formation. Notorious pests like spider mites thrive in areas with high temperatures (32–35 °C), and it is predicted that the size and number of such areas will expand in the coming decades. Higher temperatures can directly accelerate population growth, but also indirectly affect them through ch...
N supply mediates the radiative balance of N 2 O emissions and CO 2 sequestration driven by N‐fixing vs. non‐fixing treesNARA Subscribed
Forests are a significant CO 2 sink. However, CO 2 sequestration in forests is radiatively offset by emissions of nitrous oxide (N 2 O), a potent greenhouse gas, from forest soils. Reforestation, an important strategy for mitigating climate change, has focused on maximizing CO 2 sequestration in plant biomass without integrating N 2 O emissions from soils. Although nitrogen (N)‐fixing trees are often recommended for reforestat...
Estimating Emissions from Electricity Generation Using Electricity Dispatch Models: The Importance of System Operating ConstraintsNARA Subscribed
Summary This article develops a modeling approach for estimating emissions (e.g., carbon dioxide) from nuclear, coal, natural gas, and hydropower generators in reaction to short‐term changes to electricity demand. The modeling approach accounts for a set of operating constraints (OCs), including scheduled maintenance, forced outage, spinning reserves, fuel switching, seasonal output capacities, and seasonal hydro resource avai...
Quantifying invasion resistance: the use of recruitment functions to control for propagule pressureNARA Subscribed
Invasive species distributions tend to be biased towards some habitats compared to others due to the combined effects of habitat‐specific resistance to invasion and non‐uniform propagule pressure. These two factors may also interact, with habitat resistance varying as a function of propagule supply rate. Recruitment experiments, in which the number of individuals recruiting into a population is measured under different propagu...
A global synthesis of plant extinction rates in urban areasNARA Subscribed
Plant extinctions from urban areas are a growing threat to biodiversity worldwide. To minimize this threat, it is critical to understand what factors are influencing plant extinction rates. We compiled plant extinction rate data for 22 cities around the world. Two‐thirds of the variation in plant extinction rates was explained by a combination of the city’s historical development and the current proportion of native vegetation...