Publications by authors named "Alastair Graham"

Over 15 000 species of fishes are found globally in the marine environment and DNA barcodes are used extensively to describe, catalogue, understand and manage this diversity. The dataset outlined here represents a DNA barcode reference library of the mitochondrial cytochrome c oxidase subunit 1 gene (COI) from 9767 voucher specimens (representing at least 2220 species and 288 families) of marine fishes. This publicly available dataset in the Barcode of Life Data System (BOLD) represents 17 years (2005-2022) of barcoding of marine fishes identified from Australian territorial waters.

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Knowledge gaps about how the ocean melts Antarctica's ice shelves, borne from a lack of observations, lead to large uncertainties in sea level predictions. Using high-resolution maps of the underside of Dotson Ice Shelf, West Antarctica, we reveal the imprint that ice shelf basal melting leaves on the ice. Convection and intermittent warm water intrusions form widespread terraced features through slow melting in quiescent areas, while shear-driven turbulence rapidly melts smooth, eroded topographies in outflow areas, as well as enigmatic teardrop-shaped indentations that result from boundary-layer flow rotation.

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Today, relatively warm Circumpolar Deep Water is melting Thwaites Glacier at the base of its ice shelf and at the grounding zone, contributing to significant ice retreat. Accelerating ice loss has been observed since the 1970s; however, it is unclear when this phase of significant melting initiated. We analyzed the marine sedimentary record to reconstruct Thwaites Glacier's history from the early Holocene to present.

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Background: While female sex has been associated with worse outcomes following coronary revascularization, previous analyses in left main coronary artery (LMCA) disease have been conflicting. In addition, a signal that increased mortality may be specific to women treated with percutaneous coronary intervention (PCI) requires further investigation.

Methods: Nordic-Baltic-British left main revascularization study (NOBLE) was a randomized trial comparing PCI to coronary artery bypass surgery (CABG) in patients with LMCA disease.

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Background: In the treatment of left main coronary artery (LMCA) disease, patients' age may affect the clinical outcome after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). This study stratified the clinical outcome according to the age of patients treated for LMCA stenosis with PCI or CABG in the Nordic-Baltic-British Left Main Revascularization (NOBLE) study.

Methods: Patients with LMCA disease were enrolled in 36 centers in northern Europe and randomized 1:1 to treatment by PCI or CABG.

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Background: We have entered an era of renewed interest in novel approaches to surgical intervention and minimally invasive and transcatheter technique. With an aging population, isolated tricuspid valve regurgitation incidence is rising; however, referral for surgical intervention remains low.

Aims: We undertook this retrospective review to assess outcomes and challenges associated with tricuspid valve intervention.

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Background: Percutaneous coronary intervention (PCI) is increasingly used in revascularisation of patients with left main coronary artery disease in place of the standard treatment, coronary artery bypass grafting (CABG). The NOBLE trial aimed to evaluate whether PCI was non-inferior to CABG in the treatment of left main coronary artery disease and reported outcomes after a median follow-up of 3·1 years. We now report updated 5-year outcomes of the trial.

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Faunal assemblages at hydrothermal vents associated with island-arc volcanism are less well known than those at vents on mid-ocean ridges and back-arc spreading centres. This study characterizes chemosynthetic biotopes at active hydrothermal vents discovered at the Kemp Caldera in the South Sandwich Arc. The caldera hosts sulfur and anhydrite vent chimneys in 1375-1487 m depth, which emit sulfide-rich fluids with temperatures up to 212°C, and the microbial community of water samples in the buoyant plume rising from the vents was dominated by sulfur-oxidizing Gammaproteobacteria.

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Reductions in the thickness and extent of Antarctic ice shelves are triggering increased discharge of marine-terminating glaciers. While the impacts of recent changes are well documented, their role in modulating past ice-sheet dynamics remains poorly constrained. This reflects two persistent issues; first, the effective discrimination of sediments and landforms solely attributable to sub-ice-shelf deposition, and second, challenges in dating these records.

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Objective: This study was undertaken to assess the potential value of preoperative blood components as prognostic markers of outcome after lung cancer resection, and hence their potential to aid in the selection of patients for curative surgery.

Methods: This was a single-center study on 313 patients who underwent surgery for non-small-cell lung cancer from 2006 to 2008. Data were analyzed retrospectively from a prospectively maintained thoracic database.

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Satellite imagery reveals flowstripes on Foundation Ice Stream parallel to ice flow, and meandering features on the ice-shelf that cross-cut ice flow and are thought to be formed by water exiting a well-organised subglacial system. Here, ice-penetrating radar data show flow-parallel hard-bed landforms beneath the grounded ice, and channels incised upwards into the ice shelf beneath meandering surface channels. As the ice transitions to flotation, the ice shelf incorporates a corrugation resulting from the landforms.

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Background: The aim of this study was to assess the inter observer and intra observer reliability of acute scaphoid fracture classification methods including a novel 'long axis' measurement, a simple method which we have developed with the aim of improving agreement when describing acute fractures.

Methods: We identified sixty patients with acute scaphoid fractures at two centres who had been investigated with both plain radiographs and a CT (Computed Tomography) scan within 4 weeks of injury. The fractures were assessed by three observers at each centre using three commonly used classification systems and the 'long axis' method.

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This article describes the key features of realist (realistic) evaluation and illustrates their application using, as an example, a simulation-based course for final year medical students. The use of simulation-based education (SBE) is increasing and so too is the evidence supporting its value as a powerful technique which can lead to substantial educational benefits. Accompanying these changes is a call for research into its use to be more theory-driven and to investigate both 'Did it work?' and as importantly 'Why did it work (or not)?' An evaluation methodology that is capable of answering both questions is realist evaluation.

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The retreating Pine Island Glacier (PIG), West Antarctica, presently contributes ~5-10% of global sea-level rise. PIG's retreat rate has increased in recent decades with associated thinning migrating upstream into tributaries feeding the main glacier trunk. To project future change requires modelling that includes robust parameterisation of basal traction, the resistance to ice flow at the bed.

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Introduction: Simulation-based medical education (SBME) is an accepted learning methodology with an ever-expanding evidence base. Concerns have been expressed that research output in SBME lacks explicit links to educational theory. Using the 'Description, Justification and Clarification' framework we have investigated the extent to which SBME conference abstracts declare the educational theory underpinning their studies.

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The history of glaciations on Southern Hemisphere sub-polar islands is unclear. Debate surrounds the extent and timing of the last glacial advance and termination on sub-Antarctic South Georgia in particular. Here, using sea-floor geophysical data and marine sediment cores, we resolve the record of glaciation offshore of South Georgia through the transition from the Last Glacial Maximum to Holocene.

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Article Synopsis
  • - The study compared the effectiveness of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) in treating patients with left main coronary artery disease, analyzing outcomes related to major adverse cardiac or cerebrovascular events (MACCE) over 5 years.
  • - A total of 1201 patients were enrolled, with 598 receiving PCI and 603 receiving CABG; the 5-year MACCE rate was significantly higher for PCI at 29%, compared to 19% for CABG, indicating that CABG had better long-term outcomes.
  • - The results showed that PCI was found to be inferior to CABG for this patient population, as evidenced by higher MACCE rates (HR 1.48
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We present the case of 56-year-old woman who required complex coronary artery bypass grafting for high-risk anomalous left main coronary artery (LMCA) originating from right coronary cusp including conventional reimplantation of the LMCA plus left internal mammary artery (LIMA) graft to the left anterior descending (LAD) and saphenous vein graft (SVG) to the left circumflex (LCx). On subsequent cardiac computed tomography screening and cardiac catheterization, the LIMA graft was occluded after just a few centimeters, but the SVG graft was patent with good run-off into the native LCx and also filled the LAD retrogradely. The reimplanted left main stem demonstrated at least moderate ostial stenosis although pressure wire assessment of this was not significant (fractional flow reserve 0.

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Objectives: Repeat sternotomy for redo cardiac surgery may be associated with catastrophic injuries to mediastinal structures. The purpose of this study was to determine the frequency of these injuries, associated outcome and if a preoperative computerized tomography (CT) scan reduces the risk of re-entry injury.

Methods: Five hundred and forty-four patients who underwent redo cardiac surgery between 2001 and 2011 were identified by review of our unit's prospectively maintained cardiac surgery database.

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Systolic anterior motion of the mitral leaflet causing left ventricular outflow tract obstruction is commonly seen in hypertrophic cardiomyopathy and also in patients with advanced mitral valve disease with excessive anterior leaflet tissue or a reduced aortic-mitral angle. We describe 2 octogenarians who presented with systolic mitral leaflet anterior motion in advanced mitral valve disease with severe mitral annular calcification and associated asymmetrical septal hypertrophy.

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