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Climatic and Hydrological Changes Drive Contemporary Fire Regime Transitions in the World's Largest WetlandNARA Subscribed
Tropical wetlands have historically been resilient to fire, but ongoing climate and hydrological changes are undermining this stability. Here, we provide robust multi‐decadal evidence (1985–2024) of structural changes in the contemporary fire regime of the Pantanal, the world's largest wetland, associated with hydroclimatic disruption. We investigated changes in burned area, mean fire size, and fire seasonality using hydrologi...
Cephalopods play a key role in marine ecosystems but are difficult to study directly; hence, beaks recovered from predator stomachs are critical to further understand their distribution and ecology. Cephalopod species have traditionally been identified from beak morphology, a time-consuming method limited by degree of beak digestion, lack of specialist expertise, and limited coverage in reference collections. Here, we provide...
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...
Local and Landscape‐Level Environmental Conditions Drive Habitat Selection Across Terrestrial Mammal SpeciesNARA Subscribed
Aim Animal movements are a fundamental process affecting communities and ecosystems. Quantifying habitat selection across species and habitats is key for understanding how animals respond to environmental change. Currently, we lack comparative studies that examine how habitat selection varies across species traits and landscapes. We aim to quantify global patterns of habitat selection to help understand the fundamental drivers...
Aim Foundation species sustain biodiversity by providing habitat, resources, and protection from environmental stress. However, their influence on environmental severity and variability and their role in shaping diversity across spatial scales remain poorly understood. We conducted a large‐scale study to assess how environmental conditions and community diversity vary between areas with and without canopy‐forming macroalgae ac...
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...
Jones Sound is one of three critical waterways in the Canadian Arctic Archipelago that regulate liquid exchange between the Arctic Ocean and northern Atlantic Ocean. However, to date, no high-resolution ocean circulation model exists to study the recent evolution of Jones Sound, meaning that our understanding of circulation within the sound is based either on temporally and spatially sparse oceanographic observations or on ext...
Proximity to natural habitat is known to enhance pollination services in large‐scale agriculture, but it remains unclear whether this holds in tropical smallholder farms. These systems are embedded in ecologically complex landscapes, central to global food security, and depend heavily on biodiversity‐derived ecosystem services. We conducted a systematic review and meta‐analysis of 35 studies assessing the relationship between...
CD8 + T cells exhibit distinct changes with aging, including a diminished naïve cell pool, an expansion of memory and exhausted cells, and altered effector molecule production, altogether leading to increased susceptibility to infection. They have reduced cytotoxicity in vivo, but increased granule content and faster cytotoxic kinetics to target cells in vitro . Whether CD8 + T cells from old mice degranulate when activated in...
Trophic Interactions Are Key to Understanding the Effects of Global Change on the Distribution and Functional Role of the Brown BearNARA Subscribed
Biotic interactions are expected to influence species' responses to global changes, but they are rarely considered across broad spatial extents. Abiotic factors are thought to operate at larger spatial scales, while biotic factors, such as species interactions, are considered more important at local scales within communities, in part because of the knowledge gap on species interactions at large spatial scales (i.e., the Eltoni...
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...
Cerebral hypoperfusion, brain structural integrity, and cognitive impairment in older APOE4 carriersNARA Subscribed
Cerebral blood flow (CBF) deficits, cognitive decline, and brain structural changes have been reported in older adults with and without apolipoprotein E-e4 ( APOE4 )-related risk for dementia. However, it remains unclear whether brain structural changes mediate the effects of hypoperfusion on cognitive impairment in APOE4 carriers and non-carriers. We studied 166 (60–89 years) APOE4 carriers (ε3/ε4 or ε4/ε4) and APOE3 homozygo...