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Dryland ecosystems cover 41% of Earth's land surfaces, account for 44% of cultivated lands and 60% of food sources, and make large contributions to the global water and carbon cycles. However, these ecosystems are experiencing unprecedented extremes including heatwaves, floods, and droughts as well as hotter temperatures and often declining water resource availability. These ecosystems are some of the most challenging to monit...
A climate region classification for California’s warm season: apparent temperature clustering to support heat-health epidemiologyNARA Subscribed
Climate classification enhances our understanding of regional climate patterns and enables a science-based framework for assessing environmental and public health relationships. Prior climate classification systems are limited in their ability to capture variation across dynamic subclimates, particularly in the context of complex topographical, elevation, and meteorological characteristics such as California, United States. In...
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...
The Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE)™ trial was a randomized, 2-year controlled trial of caloric restriction (CR) versus an ad libitum (AL) control condition in nonobese humans. We performed exploratory analyses of muscle mitochondrial DNA (mtDNA) integrity, one element of mitochondrial quality. Our aims were to assess the feasibility of this approach, explore associations to...
IND-enabling preclinical studies of [11C]COU, a trapped metabolite PET radiotracer for monoamine oxidase-BNARA Subscribed
[ 11 C]COU is a trapped metabolite radiotracer for in vivo analysis of Monoamine Oxidase B activity using positron emission tomography (PET) imaging. [ 11 C]COU has the potential to quantify astrocytosis in the early stages of Alzheimer’s disease, providing an earlier marker of disease than currently available for staging disease progression. Prior preclinical studies have demonstrated the efficacy of this radiotracer in precl...
Species Richness Gradients Vary Across Phylogenetic ScalesNARA Subscribed
Aim To determine how species richness gradients—commonly considered universal—vary across the phylogenetic hierarchy of birds and mammals, and to uncover how clade age and size predetermine the gradients. Location Global. Time Period Last 120 million years. Taxa Studied Birds and mammals (~15,000 species). Methods We used large‐scale phylogenies of birds and mammals and captured the species richness gradient for each of their...