Publications by authors named "Downs R"

Understanding changes in material properties through external stimuli plays a key role in validating the expected performance of materials and engineering material properties in a controlled manner. Here, we introduce a fundamental protocol to deduce dehydration reactions kinetics of water confined in nanopore channels, with the cyclosilicate beryl as the scaffold of interest, using time-resolved synchrotron X-ray diffraction (SXRD), in the temperature interval of 298-1038 K. The temperature-dependent intensity of the strongest reflection (112) was used as the crystallite variable.

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Molecular assembly indices, which measure the number of unique sequential steps theoretically required to construct a three-dimensional molecule from its constituent atomic bonds, have been proposed as potential biosignatures. A central hypothesis of assembly theory is that any molecule with an assembly index ≥15 found in significant local concentrations represents an unambiguous sign of life. We show that abiotic molecule-like heteropolyanions, which assemble in aqueous solution as precursors to some mineral crystals, range in molecular assembly indices from 2 for HCO or Si(OH) groups to as large as 21 for the most complex known molecule-like subunits in the rare minerals ewingite and ilmajokite.

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The locations of minerals and mineral-forming environments, despite being of great scientific importance and economic interest, are often difficult to predict due to the complex nature of natural systems. In this work, we embrace the complexity and inherent "messiness" of our planet's intertwined geological, chemical, and biological systems by employing machine learning to characterize patterns embedded in the multidimensionality of mineral occurrence and associations. These patterns are a product of, and therefore offer insight into, the Earth's dynamic evolutionary history.

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Sonic boom measurements from recent flight tests have provided an opportunity to investigate effects of microphone installation on sonic boom waveforms, spectra, and metric levels in support of NASA X-59 flight test planning. While those flight tests used N-wave aircraft (F-18s), modeling studies were also conducted using source characteristics for a shaped low-boom aircraft. Of particular interest were the effects of receiver height on boom waveforms and metrics at elevated receiver positions, microphone installation, and local ground cover type.

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Analysis of manganese mineral occurrences and valence states demonstrate oxidation of Earth's crust through time. Changes in crustal redox state are critical to Earth's evolution, but few methods exist for evaluating spatially averaged crustal redox state through time. Manganese (Mn) is a redox-sensitive metal whose variable oxidation states and abundance in crustal minerals make it a useful tracer of crustal oxidation.

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Mars' sedimentary rock record preserves information on geological (and potential astrobiological) processes that occurred on the planet billions of years ago. The rover is exploring the lower reaches of Mount Sharp, in Gale crater on Mars. A traverse from Vera Rubin ridge to Glen Torridon has allowed to examine a lateral transect of rock strata laid down in a martian lake ~3.

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Minerals contain important clues to understanding the complex geologic history of Earth and other planetary bodies. Therefore, geologists have been collecting mineral samples and compiling data about these samples for centuries. These data have been used to better understand the movement of continental plates, the oxidation of Earth's atmosphere and the water regime of ancient martian landscapes.

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Hereditary hypophosphatemic disorders, TIO, and CKD conditions are believed to be influenced by an excess of Fibroblast Growth Factor-23 (FGF-23) which activates a binary renal FGFRs / α-Klotho complex to regulate homeostatic metabolism of phosphate and vitamin D. Adaptive FGF-23 responses from CKD patients with excess FGF-23 frequently lead to increased mortality from cardiovascular disease. A reversibly binding small molecule therapeutic has yet to emerge from research and development in this area.

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Agitated patients presenting to the emergency department (ED) can escalate to aggressive and violent behaviors with the potential for injury to themselves, ED staff, and others. Agitation is a nonspecific symptom that may be caused by or result in a life-threatening condition. Project BETA (Best Practices in the Evaluation and Treatment of Agitation) is a compilation of the best evidence and consensus recommendations developed by emergency medicine and psychiatry experts in behavioral emergencies to improve our approach to the acutely agitated patient.

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The rover's exploration of rocks and soils in Gale crater has provided diverse geochemical and mineralogical data sets, underscoring the complex geological history of the region. We report the crystalline, clay mineral, and amorphous phase distributions of four Gale crater rocks from an 80-m stratigraphic interval. The mineralogy of the four samples is strongly influenced by aqueous alteration processes, including variations in water chemistries, redox, pH, and temperature.

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As information and communication technology has become pervasive in our society, we are increasingly dependent on both digital data and repositories that provide access to and enable the use of such resources. Repositories must earn the trust of the communities they intend to serve and demonstrate that they are reliable and capable of appropriately managing the data they hold.

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Article Synopsis
  • Fasciola hepatica is a parasitic trematode that impacts livestock and humans, causing disease and economic loss, with increasing resistance to current treatments.
  • The study focuses on the interaction of two glycan-binding proteins, LGALS-11 and LGALS-14, with F. hepatica proteins, revealing novel insights into potential vaccine candidates.
  • LGALS-14 identified a larger number of interacting proteins than LGALS-11, including previously tested vaccine candidates, indicating its significance in understanding host-parasite dynamics.
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Neutrophils are rapidly deployed innate immune cells, and excessive recruitment is causally associated with influenza-induced pathologic conditions. Despite this, the complete set of influenza lethality-associated neutrophil effector proteins is currently unknown. Whether the expression of these proteins is predetermined during bone marrow (BM) neutrophil maturation or further modulated by tissue compartment transitions has also not been comprehensively characterized at a proteome-wide scale.

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In this study two community psychology students describe their experiences in participating in different types of "green" volunteer sustainable programs. In the first scenario, Anthonie Collins describes his experiences in working with young men in a youth detention facility and how the participants discovered the intrinsic value of maintaining a vegetable community garden. In the second scenario, Jordan Seitz describes her experiences in organizing a community apple harvest at a local fruit tree orchard in Wyoming, MN.

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Cavernous hemangiomas with an intrasellar extension are very rare, generally benign lesions that manifest by the compression of nearby structures. The presenting symptoms usually range from visual disturbances to an endocrine imbalance. Occasional extension into the cavernous sinus has been reported, which can cause cranial nerve compression.

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Intracranial vascular pathologies often have overlapping clinical presentations. Dissected vessel occlusions and bifurcation aneurysms can appear similar on pretherapeutic imaging. The medical management of these two entities is drastically different.

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Intracranial vascular pathologies often have overlapping clinical presentations. Dissected vessel occlusions and bifurcation aneurysms can appear similar on pretherapeutic imaging. The medical management of these two entities is drastically different.

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Background: Pilocytic astrocytoma is a low-grade central nervous system tumor most commonly seen in children. Dissemination from a primary intracranial tumor along the neuroaxis has been described at both presentation and disease progression. However, the development of an intradural extramedullary pilocytic astrocytoma independent of a primary intraparenchymal tumor in an adult patient with no history of pilocytic astrocytoma has rarely been reported.

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Clay minerals provide indicators of the evolution of aqueous conditions and possible habitats for life on ancient Mars. Analyses by the Mars Science Laboratory rover Curiosity show that ~3.5-billion year (Ga) fluvio-lacustrine mudstones in Gale crater contain up to ~28 weight % (wt %) clay minerals.

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is the most pathogenic nematode of small ruminants. Infection in sheep and goats results in anaemia that decreases animal productivity and can ultimately cause death. The involvement of ruminant-specific galectin-11 (LGALS-11) and galectin-14 (LGALS-14) has been postulated to play important roles in protective immune responses against parasitic infection; however, their ligands are unknown.

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The Mars Science Laboratory Curiosity rover performed coordinated measurements to examine the textures and compositions of aeolian sands in the active Bagnold dune field. The Bagnold sands are rounded to subrounded, very fine to medium sized (~45-500 μm) with ≥6 distinct grain colors. In contrast to sands examined by Curiosity in a dust-covered, inactive bedform called Rocknest and soils at other landing sites, Bagnold sands are darker, less red, better sorted, have fewer silt-sized or smaller grains, and show no evidence for cohesion.

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Purpose: Microarray and RNA sequencing studies in the chick model of early optically induced refractive error have implicated thousands of genes, many of which have also been linked to ocular pathologies in humans, including age-related macular degeneration (AMD), choroidal neovascularization, glaucoma, and cataract. These findings highlight the potential relevance of the chick model to understanding both refractive error development and the progression to secondary pathological complications. The present study aimed to determine whether proteomic responses to early optical defocus in the chick share similarities with these transcriptome-level changes, particularly in terms of dysregulation of pathology-related molecular processes.

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Caffeine is a highly catabolic dietary stimulant. High caffeine concentrations (1-10 mM) have previously been shown to inhibit protein synthesis and increase protein degradation in various mammalian cell lines. The purpose of this study was to examine the effect of short-term caffeine exposure on cell signaling pathways that regulate protein metabolism in mammalian skeletal muscle cells.

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