11 research outputs found

    Spatial Relationships between Pockmarks and Sub-Seabed Gas in Fjordic Settings: Evidence from Loch Linnhe, West Scotland

    Get PDF
    Sub-seabed gas is commonly associated with seabed depressions known as pockmarks—the main venting sites for hydrocarbon gases to enter the water column. Sub-seabed gas accumulations are characterized by acoustically turbid or opaque zones in seismic reflection profiles, taking the form of gas blankets, curtains or plumes. How the migration of sub-seabed gas relates to the origin and distribution of pockmarks in nearshore and fjordic settings is not well understood. Using marine geophysical data from Loch Linnhe, a Scottish fjord, we show that shallow sub-seabed gas occurs predominantly within glaciomarine facies either as widespread blankets in basins or as isolated pockets. We use geospatial ‘hot-spot’ analysis conducted in ArcGIS to identify clusters of pockmarks and acoustic (sub-seabed) profile interpretation to identify the depth to gas front across the fjord. By combining these analyses, we find that the gas below most pockmarks in Loch Linnhe is between 1.4 m and 20 m deep. We anticipate that this work will help to understand the fate and mobility of sedimentary carbon in fjordic (marine) settings and advise offshore industry on the potential hazards posed by pockmarked seafloor regions even in nearshore settings

    Peer reviewers in 2017

    Get PDF
    Pockmarks are seabed depressions that represent primary evidence of rapid biogenic/thermogenic gas build up and fluid release from seabed sediments to the water column. We use a Geographical Information System (GIS) to analyse multibeam echo-sounder bathymetric data and use a range of semi-automated tools to map seabed pockmarks in fjords and adjacent coastal waters around western Scotland. We map 1019 individual pockmarks in 12 different hydrographic areas covering ca. 2019 km2. We use morphological metrics and statistical procedures to classify and analyse the variety of pockmark forms. A k-means clustering algorithm identifies three classes of pockmark morphology: deep, elongate and regular. The recognition of separate pockmark classes could aid understanding of their age, activity and origin. This work presents the first detailed mapping of pockmark fields in Scottish west coast waters and highlights the use of pockmarks as an indicator of the quantity, mobility and fate of stored carbon

    Blood transcriptome responses in patients correlate with severity of COVID-19 disease

    Get PDF
    BackgroundCoronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Infected individuals display a wide spectrum of disease severity, as defined by the World Health Organization (WHO). One of the main factors underlying this heterogeneity is the host immune response, with severe COVID-19 often associated with a hyperinflammatory state.AimOur current study aimed to pinpoint the specific genes and pathways underlying differences in the disease spectrum and outcomes observed, through in-depth analyses of whole blood transcriptomics in a large cohort of COVID-19 participants.ResultsAll WHO severity levels were well represented and mild and severe disease displaying distinct gene expression profiles. WHO severity levels 1-4 were grouped as mild disease, and signatures from these participants were different from those with WHO severity levels 6-9 classified as severe disease. Severity level 5 (moderate cases) presented a unique transitional gene signature between severity levels 2-4 (mild/moderate) and 6-9 (severe) and hence might represent the turning point for better or worse disease outcome. Gene expression changes are very distinct when comparing mild/moderate or severe cases to healthy controls. In particular, we demonstrated the hallmark down-regulation of adaptive immune response pathways and activation of neutrophil pathways in severe compared to mild/moderate cases, as well as activation of blood coagulation pathways.ConclusionsOur data revealed discrete gene signatures associated with mild, moderate, and severe COVID-19 identifying valuable candidates for future biomarker discovery

    Scotland's pockmarks: understanding their formation and relationship to buried carbon in fjordic systems

    No full text
    Pockmarks are concave seabed depressions formed by the venting of sub-seabed fluids into the water column. These fluids can contain greenhouse gases such as methane and carbon dioxide, formed by the microbial breakdown of organic carbon, thus creating a strong link between pockmarks and the marine carbon cycle. Pockmarks have been reported from the offshore waters around the UK, but until now no detailed study has been conducted on pockmarks in Scottish waters. It is important to understand the processes that lead to pockmark formation in order to assess their activity status and morphological evolution. Twelve study areas around western Scotland were selected, where pockmarks are observed, with three primary research aims: (i) to map the location and morphological characteristics of pockmarks; (ii) to map the distribution of sub-seabed gas and its spatial association with pockmarks; (iii) to characterise the physical and geochemical sediment stratigraphy from inside and outside pockmarks. Using statistical GIS methods, pockmark morphologies and distributions have been mapped and used to construct a classification system. The physical and geochemical stratigraphy of five sediment cores have also been analysed at a mm-scale resolution. 1015 previously unreported pockmarks have been mapped around western Scotland and separated into three distinct classes: common, elongated and deep; from which pockmark activity status can be inferred. This research has found that localised pockmark hot-spots are probably associated with areas of higher organic carbon within fjordic and extra-fjordic environments; these are not currently included in national carbon inventories. Finally, the geochemical analysis has shown that a shallowing of the redox zone inferred from Mn/ Fe ratio may provide a useful proxy for recent pockmark activity. These results will aid the assessment of pockmarks when considering geohazards and promote future research on the importance of pockmarks supporting vulnerable marine biotopes

    Transformation of Australian Community Pharmacies Into Good Clinical Practice Compliant Trial Pharmacies for HIV Pre-Exposure Prophylaxis

    Get PDF
    Background: In Australia, clinical trial drugs are conventionally dispensed through clinical trial pharmacies only, while community pharmacies dispense drugs approved by Australia's regulatory body. A large HIV pre-exposure prophylaxis study aimed to deliver clinical trial drug through community pharmacies to improve convenience and mimic real world prescribing. This paper describes the process of making community trials compliant with good clinical practice and reports outcomes of delivering clinical trial drug through community pharmacies. Methods: Eight community and four clinical trial pharmacies across three Australian states were approached to participate. A good clinical practice checklist was generated and pharmacies underwent a number of changes to meet clinical trial pharmacy requirements prior to study opening. Changes were made to community pharmacies to make them compliant with good clinical trial practice including; staff training, structural changes, and implementing monitoring of study drug and prescribing practices. Study drug was ordered through standard clinical trial processes and dispensed from study pharmacies by accredited pharmacists. Throughout the trial, record logs for training, prescriber signature and delegation, temperature, participant, and drug accountability were maintained at each pharmacy. The study team monitored each log and delivered on-site training to correct protocol variations. Results: Each pharmacy that was approached agreed to participate. All community pharmacies achieved good clinical practice compliance prior to dispensing study drug. Over the course of the study, 20,152 dispensations of study drug occurred, 83% of these occurred at community pharmacies. Only 2.0% of dispensations had an error, and errors were predominantly minor. On five occasions a pharmacist who was not accredited dispensed study drug. Conclusions: Community based pharmacies can undergo training and modifications to achieve good clinical practice compliance and dispense clinical trial study drug. Community based pharmacies recorded few variations from study protocol. Community based pharmacies offer a useful alternative to clinical trial pharmacies to increase convenience for study participants and expanded use of these pharmacies should be considered for large clinical trials, including HIV prevention trials
    corecore