120 research outputs found

    The West Coast range, Tasmania: mountains and geological giants

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    It has long been believed that, with the exception of mounts Sorell and Strahan, the peaks of the West Coast Range, western Tasmania, were named by Charles Gould, first Tasmanian Government Geologist, during his three epic journeys to the region undertaken between 1860 and 1862. Although the peaks were named after nineteenth-century men of outstanding achievement in science, all Fellows of the Geological Society of London, only four (Murchison, Sedgwick, Lyell and Owen) were named by Gould at the time of his journeys and two (Huxley and Jukes) were probably named by him at a later time. Three other peaks (Darwin, Geikie and Read) and the Tyndall Range were named directly or indirectly by Thomas Bather Moore

    Devonian lamprophyres from Mt Lyell, western Tasmania

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    Mica concentrated from a post-cleavage lamprophyre occurring at the Prince Lyell Mine, Queenstown, has yielded a K-Ar age of 363±3 Ma (latest Devonian). This minette is the first confirmed evidence of Devonian potassic la mprophyric activity from Tasmania and places an upper constraint on Devonian ductile deformation in western Tasmania

    Sedimentary and structural features of the Bell shale correlate (Early Devonian), Strahan quadrangle, western Tasmania.

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    The sequence of interbedded mudstone, siltstone and very fine sandstone in the Strahan Quadrangle, correlated with the Bell Shale is at least 500 m thick. Two broad associations can be defined. The ratio of very fine sand to mud in the lower association is between 3:2 and 2:3 whereas in the upper association only occasional thin sandstone beds occur. Sedimentary structures such as lenticular bedding, symmetrical ripple marks and the lack of deep water sedimentary features suggest that deposition took place in shallow water. This is supported by palaeontological evidence. Some scouring and upward fining beds suggest that deposition from waning currents occurred sporadically within this environment. The Bell Shale correlate has been folded during two phases. The first phase produced folds plunging between 300 and 900 NW and the second phase produced folds plunging shallowly WNW or ESE. Cleavage was developed only locally during each phase. Folds of both phases produced a primary axial surface cleavage and the second phase produced crenulation cleavage in some areas. The amplitude of folds produced during the first phase decreases towards the centre of the basin. The locus of strain during the second phase of deformation was along the Firewood Siding Fault. The existence and timing of these deformation events demonstrates the uniformity in orientation of Tabberabberan structures throughout north and western Tasmania

    Late Pleistocene marine sediments and fossils from Mussel Roe Bay, northeastern Tasmania

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    Foraminifera- and mollusc-bearing estuarine sediments were encountered in one of a series of auger holes drilled in Late Pleistocene interglacial sands at Mussel Roe Bay, northeastern Tasmania. It is proposed that the estuary formed behind a bay-mouth barrier similar to that presently occurring between Mussel Roe Bay and Great Mussel Roe Bay

    Stratigraphic relationships of Late Ordovician to Early Devonian rocks in the Huntley Quadrangle, south-western Tasmania

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    During mapping of the Huntley Quadrangle in south-western Tasmania, two new, important, graptolite-trilobite-brachiopod bearing sequences were found in the upper part of the Lower Palaeozoic succession. The stratigraphy of these sequences is described. To avoid confusion a new group and a new formation, which includes the Westfield Beds (sensu Corbett and Banks 1974), are proposed

    Prospective validation of the 4C prognostic models for adults hospitalised with COVID-19 using the ISARIC WHO Clinical Characterisation Protocol

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    Purpose: To prospectively validate two risk scores to predict mortality (4C Mortality) and in-hospital deterioration (4C Deterioration) among adults hospitalised with COVID-19. // Methods: Prospective observational cohort study of adults (age ≥18 years) with confirmed or highly suspected COVID-19 recruited into the International Severe Acute Respiratory and emerging Infections Consortium (ISARIC) WHO Clinical Characterisation Protocol UK (CCP-UK) study in 306 hospitals across England, Scotland and Wales. Patients were recruited between 27 August 2020 and 17 February 2021, with at least 4 weeks follow-up before final data extraction. The main outcome measures were discrimination and calibration of models for in-hospital deterioration (defined as any requirement of ventilatory support or critical care, or death) and mortality, incorporating predefined subgroups. // Results: 76 588 participants were included, of whom 27 352 (37.4%) deteriorated and 12 581 (17.4%) died. Both the 4C Mortality (0.78 (0.77 to 0.78)) and 4C Deterioration scores (pooled C-statistic 0.76 (95% CI 0.75 to 0.77)) demonstrated consistent discrimination across all nine National Health Service regions, with similar performance metrics to the original validation cohorts. Calibration remained stable (4C Mortality: pooled slope 1.09, pooled calibration-in-the-large 0.12; 4C Deterioration: 1.00, –0.04), with no need for temporal recalibration during the second UK pandemic wave of hospital admissions. // Conclusion: Both 4C risk stratification models demonstrate consistent performance to predict clinical deterioration and mortality in a large prospective second wave validation cohort of UK patients. Despite recent advances in the treatment and management of adults hospitalised with COVID-19, both scores can continue to inform clinical decision making

    Development and validation of the ISARIC 4C Deterioration model for adults hospitalised with COVID-19: a prospective cohort study

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    BACKGROUND: Prognostic models to predict the risk of clinical deterioration in acute COVID-19 cases are urgently required to inform clinical management decisions. METHODS: We developed and validated a multivariable logistic regression model for in-hospital clinical deterioration (defined as any requirement of ventilatory support or critical care, or death) among consecutively hospitalised adults with highly suspected or confirmed COVID-19 who were prospectively recruited to the International Severe Acute Respiratory and Emerging Infections Consortium Coronavirus Clinical Characterisation Consortium (ISARIC4C) study across 260 hospitals in England, Scotland, and Wales. Candidate predictors that were specified a priori were considered for inclusion in the model on the basis of previous prognostic scores and emerging literature describing routinely measured biomarkers associated with COVID-19 prognosis. We used internal-external cross-validation to evaluate discrimination, calibration, and clinical utility across eight National Health Service (NHS) regions in the development cohort. We further validated the final model in held-out data from an additional NHS region (London). FINDINGS: 74 944 participants (recruited between Feb 6 and Aug 26, 2020) were included, of whom 31 924 (43·2%) of 73 948 with available outcomes met the composite clinical deterioration outcome. In internal-external cross-validation in the development cohort of 66 705 participants, the selected model (comprising 11 predictors routinely measured at the point of hospital admission) showed consistent discrimination, calibration, and clinical utility across all eight NHS regions. In held-out data from London (n=8239), the model showed a similarly consistent performance (C-statistic 0·77 [95% CI 0·76 to 0·78]; calibration-in-the-large 0·00 [-0·05 to 0·05]); calibration slope 0·96 [0·91 to 1·01]), and greater net benefit than any other reproducible prognostic model. INTERPRETATION: The 4C Deterioration model has strong potential for clinical utility and generalisability to predict clinical deterioration and inform decision making among adults hospitalised with COVID-19. FUNDING: National Institute for Health Research (NIHR), UK Medical Research Council, Wellcome Trust, Department for International Development, Bill & Melinda Gates Foundation, EU Platform for European Preparedness Against (Re-)emerging Epidemics, NIHR Health Protection Research Unit (HPRU) in Emerging and Zoonotic Infections at University of Liverpool, NIHR HPRU in Respiratory Infections at Imperial College London

    Darwin's Manufactory Hypothesis Is Confirmed and Predicts the Extinction Risk of Extant Birds

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    In the Origin of Species Darwin hypothesized that the “manufactory” of species operates at different rates in different lineages and that the richness of taxonomic units is autocorrelated across levels of the taxonomic hierarchy. We confirm the manufactory hypothesis using a database of all the world's extant avian subspecies, species and genera. The hypothesis is confirmed both in correlations across all genera and in paired comparisons controlling for phylogeny. We also find that the modern risk of extinction, as measured by “Red List” classifications, differs across the different categories of genera identified by Darwin. Specifically, species in “manufactory” genera are less likely to be threatened, endangered or recently extinct than are “weak manufactory” genera. Therefore, although Darwin used his hypothesis to investigate past evolutionary processes, we find that the hypothesis also foreshadows future changes to the evolutionary tree

    Alternative pathway dysregulation in tissues drives sustained complement activation and predicts outcome across the disease course in COVID-19

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    Complement, a critical defence against pathogens, has been implicated as a driver of pathology in COVID-19. Complement activation products are detected in plasma and tissues and complement blockade considered for therapy. To delineate roles of complement in immunopathogenesis, we undertook the largest comprehensive study of complement in an COVID-19 to date, a comprehensive profiling of 16 complement biomarkers, including key components, regulators and activation products, in 966 plasma samples from 682 hospitalised COVID-19 patients collected across the hospitalisation period as part of the UK ISARIC4C study. Unsupervised clustering of complement biomarkers mapped to disease severity and supervised machine learning identified marker sets in early samples that predicted peak severity. Compared to heathy controls, complement proteins and activation products (Ba, iC3b, terminal complement complex) were significantly altered in COVID-19 admission samples in all severity groups. Elevated alternative pathway activation markers (Ba and iC3b) and decreased alternative pathway regulator (properdin) in admission samples associated with more severe disease and risk of death. Levels of most complement biomarkers were reduced in severe disease, consistent with consumption and tissue deposition. Latent class mixed modelling and cumulative incidence analysis identified the trajectory of increase of Ba to be a strong predictor of peak COVID-19 disease severity and death. The data demonstrate that early-onset, uncontrolled activation of complement, driven by sustained and progressive amplification through the alternative pathway amplification loop is a ubiquitous feature of COVID-19, further exacerbated in severe disease. These findings provide novel insights into COVID-19 immunopathogenesis and inform strategies for therapeutic intervention
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