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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...
Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at‐sea threat...
The ecology of the Greater Caribbean manatee ( Trichechus manatus manatus ) remains underexplored in southern Central America, particularly in Panama and Costa Rica. This study presents, for the first time, significant information about their local and regional movements, connectivity, and residence times in various wetlands. Since 2016, we have employed acoustic monitoring to track the manatee population, identifying individu...
Movement behavior of a blue whale between the Galapagos Archipelago and the Frontal System off Baja California PeninsulaNARA Subscribed
The movement behavior of blue whales in the Eastern Tropical Pacific (ETP) is not well understood, especially regarding the migration of Northeast (NEP) and Southeast (SEP) Pacific populations. This study presents tracking data from a satellite‐tagged blue whale recorded between the Galapagos Islands and the Baja California Frontal System. A Bayesian state‐space model (BSAM) estimated the whale's movement trajectory, and a hid...
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...
Introduction This work presents an unsupervised learning-based methodology to identify and count unique manatees using underwater vocalization recordings. Methods The proposed approach uses Scattering Wavelet Transform (SWT) to represent individual manatee vocalizations. A Manifold Learning approach, known as PacMAP, is employed for dimensionality reduction. A density-based algorithm, known as Hierarchical Density-Based Spatia...
First evidence of prickly shark, Echinorhinus cookei Pietschmann 1928, aggregation on seamounts in the eastern Pacific, PanamaNARA Subscribed
In May 2022, twelve prickly sharks, Echinorhinus cookei Pietschmann 1928, were sighted at 151–350 m depth in the Cordillera de Coiba seamounts, Pacific Panama. This discovery expands our knowledge of the distribution and habitat use of this rare deep‐sea species. It underscores the potential significance of the Cordillera de Coiba seamounts, an offshore marine protected area, as a critical habitat for E. cookei , a species thr...
Whale sharks ( Rhincodon typus ) are found circumglobally in tropical, subtropical, and warm temperate waters, and their known seasonal aggregations and migratory movements are influenced by factors such as ocean currents, thermobiological systems, and patterns of productivity. Several locations in the eastern tropical Pacific Ocean are known habitats for R. typus ; Although it has long been known that whale sharks aggregate a...
Ecotourism focused on whales and dolphins has become a popular activity and an important source of revenue for many countries. Whale watching is vital to supporting conservation efforts and provides numerous benefits to local communities including educational opportunities and job creation. However, the sustainability of whale-based ecotourism depends on the behavior and health of whale populations and it is crucial that ecoto...
Bioerosion by the sea urchin Diadema mexicanum along Eastern Tropical Pacific coral reefsNARA Subscribed
Bioerosion is a natural process in coral reefs. It is fundamental to the health of these ecosystems. In the Eastern Tropical Pacific (ETP) coral reefs, the most important bioeroders are sponges, bivalves, sea urchins and the fish Arothron meleagris . In the 1980s, El Niño caused high coral mortality and an increase in macroalgal growth. As a result, greater sea urchin bioerosion occurred. This weakened the reef framework. Cons...
Population size and migratory connectivity of humpback whales wintering in Las Perlas Archipelago, PanamaNARA Subscribed
From 2003 to 2009, we surveyed Las Perlas Archipelago off the Pacific coast of Panama 53 times between the months of August and October to estimate abundance of humpback whales and to test for a migratory connection with populations from the southern hemisphere. We identified 295 individuals using photo‐identification of dorsal fins, including 58 calves, and the population estimate for a single season was 100–300 solitary adul...