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The Kulanaokuaiki Tephra Unit 3 (900 C.E.) was a subplinian basaltic scoria eruption, the largest known to have occurred at Kīlauea’s summit. The initiation mechanism and cause(s) of this highly hazardous eruption remain poorly understood, particularly as this style of activity has not been observed in the modern period. We use olivine diffusion timescales from Fe-Mg and lithium zoning to assess magma storage timescales and ev...
Background and aims Biological nitrogen fixation (BNF) is central to long-term pedogenesis and overall terrestrial ecosystem development. Rates of asymbiotic BNF are potentially constrained by carbon (C), phosphorus (P), and/or nitrogenase cofactor elements (e.g., iron [Fe], vanadium [V], and molybdenum [Mo]), but our understanding of the biogeochemical trajectories of cofactor elements throughout pedogenesis is limited. Metho...
Extensive phospholipid resorption from senescing leaves is not associated with phospholipid substitution in an oligotrophic heathNARA Subscribed
Background and aims In leaves, ~ 25% of phosphorus (P) is allocated to membrane phospholipids. A significant amount of leaf P is resorbed during leaf senescence to reduce plant P loss upon leaf abscission and fuel the growth of new leaves. High P resorption observed in plants on P depleted soils has been associated with extensive resorption of all P-fractions, including phospholipids, from senescent leaves. This high resorptio...
Since its consolidation as a sub‐discipline of ecology in the late 1990s, urban ecology has grown substantially, enhancing our understanding of how urbanization shapes biodiversity and how biodiversity adapts to urbanization. Inherently interdisciplinary in its scope and application, urban ecology is rooted in multiple theoretical and methodological foundations, potentially making the field overwhelming for newcomers as the ke...
Mucilage addition increases aggregate stability and tolerance of microbes to soil dryingNARA Subscribed
Background and Aims Polysaccharide-rich mucilage from plant roots alters soil structure and microbial microhabitats, potentially modifying microbial responses to drying and rewetting. Here we tested the hypotheses that mucilage strengthens soil aggregates, increases microbial survival during dry–rewet cycles, and alters respiration responses to drying and rewetting. Methods To distinguish effects arising from the physical and...
Producing functional proteins involves multiple steps during mRNA translation on the ribosomes. However, co-translational regulatory mechanisms remain poorly characterized in intact mammalian systems. As a proof-of-concept, we developed a multi-omics approach to investigate endothelial-specific, co-translational regulation by modifying the translating ribosome affinity purification (TRAP) in vivo. We simultaneously co-immunopr...
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...
Paleoenvironments of the Late Quaternary Tonica thermokarst lake, northeastern Illinois, USA, and an extinct elk‐moose ( Cervalces )NARA Subscribed
The Tonica Depression (TD), a late Quaternary sediment‐filled basin in northeastern Illinois, formed as a thermokarst lake as evidenced by a basal trash layer, its depositional history, and its occurrence on a late‐Pleistocene permafrost landscape. Stratigraphy and radiocarbon ages reveal that a multiproxy paleoenvironmental record extends throughout the late Wisconsin. Burning of organically enriched sediments has abbreviated...
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...
Effects of insect herbivory on phytoestrogen concentrations in three Trifolium speciesNARA Subscribed
Phytoestrogens are plant-produced secondary compounds believed to play a protective role against environmental stress. When consumed by animals, phytoestrogens can influence animal health and reproductive function; hence, there is interest in identifying factors that trigger their production in agricultural crops. We conducted two experiments to determine if leaf tissue herbivory by corn earworm ( Helicoverpa zea Boddie) induc...
Crown Exposure Regulates Aboveground Wood Productivity Responses to Soil Fertility in Lowland Tropical ForestsNARA Subscribed
Understanding the drivers of aboveground wood productivity (AWP) in tropical forests is crucial for explaining ecosystem functioning and predicting their responses to environmental change. While climatic water availability is a well‐established driver, the role of soil nutrients and their interaction with other resources remains uncertain. We investigated how soil nutrients and light interactions shape AWP in lowland tropical...
Microbial phosphorus in loamy, basalt-derived forest soil is altered by plant nutritional status: a root-splitting studyNARA Subscribed
Background and aims Soil nutrient content is a major driver of primary productivity. Microbial biomass comprises a substantial soil nutrient pool, the properties of which could be shaped by plant nutrient-limitation status. We aimed to determine how plant nutrition affects soil microbial biomass nitrogen (MBN) and phosphorus (MBP), and whether such effects are linked to microbial composition. Methods To isolate the effect of p...