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A somatosensory fovea in the fingertips of the Surinam toadNARA Subscribed
The Surinam toad ( Pipa pipa ) is a fully aquatic, tongueless pipid frog that captures prey using rapid suction feeding coordinated by the forelimbs. The digit tips bear distinctive lobed structures whose function has been unknown. Here we characterize the morphology, mechanical sensitivity, peripheral innervation, central representation, and behavioral function of these digit tip lobes using scanning electron microscopy, von...
Background Aspects of the gut microbiome, including presence of specific bacterial species and overall community structure, have been linked to the etiology and prognosis of colorectal cancer (CRC). Less is known about the epidemiologic risk factors that are associated with the composition of the microbiota in invasive colorectal tumors. Methods Using tumor and paired normal colorectal tissue samples from a subset of participa...
Coal mining and reclamation can have a profound influence on hydrogeologic systems, with clear consequences for groundwater quality, yet their long-term influence on downgradient water quality over time following reclamation is less well documented. Geochemical trends were evaluated in water quality downgradient of a fully reclaimed landscape at the former Big Sky Mine in the Rosebud Creek watershed (southeastern Montana, USA)...
DNA-based studies and genetic diversity indicator assessments are complementary approaches to conserving evolutionary potentialNARA Subscribed
Genetic diversity is essential for maintaining healthy populations and ecosystems. Several approaches have recently been developed to evaluate population genetic trends without necessarily collecting new genetic data. Such “genetic diversity indicators” enable rapid, large-scale evaluation across dozens to thousands of species. Empirical genetic studies, when available, provide detailed information that is important for manage...
Observations and model studies suggest that front dynamics can enhance phytoplankton productivity. This study tested whether frontal systems also increase the abundance of nitrifying microbes and nitrogen recycling during repeat sampling transects across the Mid‐Atlantic Bight shelfbreak in July 2019. We measured ammonium concentrations, nitrate dual isotopes (δ 15 N, δ 18 O), and ammonia monooxygenase subunit A ( amoA ) genes...
Dominance and rarity in tree communities across the globe: Patterns, predictors and threatsNARA Subscribed
Aim Ecological and anthropogenic factors shift the abundances of dominant and rare tree species within local forest communities, thus affecting species composition and ecosystem functioning. To inform forest and conservation management it is important to understand the drivers of dominance and rarity in local tree communities. We answer the following research questions: (1) What are the patterns of dominance and rarity in tree...
Characterizing Community Forests in the United StatesNARA Subscribed
Research on community forests (CFs), primarily governed and managed by local forest users in the United States, is limited, despite their growth in numbers over the past decade. We conducted a survey to inventory CFs in the United States and better understand their ownership and governance structures, management objectives, benefits, and financing. The ninety-eight CFs in our inventory are on private, public, and tribal lands....
Dense, cold waters formed on Antarctic continental shelves descend along the Antarctic continental margin, where they mix with other Southern Ocean waters to form Antarctic Bottom Water (AABW). AABW then spreads into the deepest parts of all major ocean basins, isolating heat and carbon from the atmosphere for centuries. Despite AABW’s key role in regulating Earth’s climate on long time scales and in recording Southern Ocean c...
Environment and shipping drive environmental DNA beta‐diversity among commercial portsNARA Subscribed
The spread of nonindigenous species by shipping is a large and growing global problem that harms coastal ecosystems and economies and may blur coastal biogeographical patterns. This study coupled eukaryotic environmental DNA (eDNA) metabarcoding with dissimilarity regression to test the hypothesis that ship‐borne species spread homogenizes port communities. We first collected and metabarcoded water samples from ports in Europe...
Changes in anxiety and depression among public health workers during the COVID-19 pandemic responseNARA Subscribed
Objectives The COVID-19 pandemic has negatively impacted mental health indicators, leading to an increase in symptoms of anxiety and depression in both the general population of adults and children and many occupational groups. This study aims to examine changes in anxiety and depression among a cohort of public health workers in the U.S. during the first year of the COVID-19 pandemic and identify potential risk factors. Metho...