Demonstrating the effectiveness of non-metallic riser flange covers for diverting leaks and jet fires using computational fluid dynamics

PresentationThe current oil and gas industry market conditions put greater emphasis of finding cost-effective design solutions while maintaining the same emphasis on process safety. Riser flange covers potentially provide a weight-saving alternative to fire walls between FPSO riser balconies and process modules, but that saving can only be realised if non-metallic materials are employed. Flanges represent the most probable leak point, and the covers are designed to entirely surround the flange and divert any leaks outboard and away from the process equipment. Therefore, any flange cover system has to be capable of resisting and diverting the flow from the largest credible leak. This work demonstrates the application of Computational Fluid Dynamics (CFD) coupled with Finite Element Analysis (FEA) to demonstrate the response of a syntactic phenolic foam and glass reinforced laminate system which combine to provide passive fire protection and thermal insulation. The work outlines a combined analytical approach to demonstrate the effectiveness of this weight-saving system for a high-flow rate gas riser. This paper describes the design of the flange cover and the materials used, the failure case against it was to protect and how that case was simulated, the fluid dynamics of the gas leak within the cover, and the stresses generated within the cover structure

Representational ethical model calibration

Equity is widely held to be fundamental to the ethics of healthcare. In the context of clinical decision-making, it rests on the comparative fidelity of the intelligence – evidence-based or intuitive – guiding the management of each individual patient. Though brought to recent attention by the individuating power of contemporary machine learning, such epistemic equity arises in the context of any decision guidance, whether traditional or innovative. Yet no general framework for its quantification, let alone assurance, currently exists. Here we formulate epistemic equity in terms of model fidelity evaluated over learnt multidimensional representations of identity crafted to maximise the captured diversity of the population, introducing a comprehensive framework for Representational Ethical Model Calibration. We demonstrate the use of the framework on large-scale multimodal data from UK Biobank to derive diverse representations of the population, quantify model performance, and institute responsive remediation. We offer our approach as a principled solution to quantifying and assuring epistemic equity in healthcare, with applications across the research, clinical, and regulatory domains

Total prostatectomy as a treatment for prostatic carcinoma in 25 dogs

Objective: To describe the complications and outcome after total prostatectomy in dogs with histologically confirmed prostatic carcinoma. Study Design: Multi-institutional retrospective case series. Animals: 25 client-owned dogs. Methods: Medical records of dogs undergoing total prostatectomy were reviewed from 2004 to 2016. Data retrieved included signalment, presenting signs, preoperative clinical findings, laboratory data, diagnostic imaging, surgical technique, histologic diagnosis, postoperative complications, occurrence of postoperative metastasis, and survival. Results: Twenty-five dogs underwent total prostatectomy for prostatic carcinoma. Urinary anastomotic techniques included urethrourethral anastomosis in 14 dogs, cystourethral anastomosis in 9 dogs, ureterocolonic anastomosis in 1 dog, and anastomosis between the bladder neck and penile urethra in 1 dog. All dogs survived to discharge. Fifteen dogs were diagnosed with transitional cell carcinoma, 8 dogs with prostatic adenocarcinoma, 1 with prostatic cystadenocarcinoma, and 1 with an undifferentiated carcinoma. Permanent postoperative urinary incontinence was present in 8 of 23 dogs. The median survival time was shorter in dogs with extracapsular tumor extension compared with those with intracapsular tumors. The overall median survival time was 231 days (range, 24-1255), with 1- and 2-year survival rates equal to 32% and 12%, respectively. Conclusion and Clinical Significance: Total prostatectomy, combined with adjunct therapies, prolongs survival and lowers complication rates compared to previous reports of dogs with prostatic carcinoma. It should be noted, however, that case selection likely played a significant role in postoperative outcome

GaInNAs-based Hellish-vertical cavity semiconductor optical amplifier for 1.3 μm operation

Hot electron light emission and lasing in semiconductor heterostructure (Hellish) devices are surface emitters the operation of which is based on the longitudinal injection of electrons and holes in the active region. These devices can be designed to be used as vertical cavity surface emitting laser or, as in this study, as a vertical cavity semiconductor optical amplifier (VCSOA). This study investigates the prospects for a Hellish VCSOA based on GaInNAs/GaAs material for operation in the 1.3-μm wavelength range. Hellish VCSOAs have increased functionality, and use undoped distributed Bragg reflectors; and this coupled with direct injection into the active region is expected to yield improvements in the gain and bandwidth. The design of the Hellish VCSOA is based on the transfer matrix method and the optical field distribution within the structure, where the determination of the position of quantum wells is crucial. A full assessment of Hellish VCSOAs has been performed in a device with eleven layers of Ga0.35In0.65N0.02As0.08/GaAs quantum wells (QWs) in the active region. It was characterised through I-V, L-V and by spectral photoluminescence, electroluminescence and electro-photoluminescence as a function of temperature and applied bias. Cavity resonance and gain peak curves have been calculated at different temperatures. Good agreement between experimental and theoretical results has been obtained

Policy as a Crime Scene

This paper explores how policy constructs the objects it seeks to regulate, taking as its case the setting of penal policy in contemporary Scotland. It employs two distinctive theoretical frames to develop the analysis: Science and Technology Studies (STS) and ‘scene theory’ a body of work in cultural studies. These offer distinctive lenses that bring into focus how the technologies of policy – statistical reports, independent Commissions, research advice – help produce populations that require intervention. The penal policy setting in question, we argue, can be understood in the same way as a crime scene, where investigators must re-construct forensically a narrative that will be legally validated. In line with the theme of this book, it offers a reflexive account of how researchers themselves are drawn into and participate as key witnesses in the scene, testifying to ‘facts’ about a crime that may have never taken place. The article aims to make the case for the potential of STS and scene theory in producing insights about our understanding of policy, particularly criminal justice policy. In doing this, it also offers a critique of the formation of the criminological discipline in a way that has side-lined policy as an ‘administrative’ rather than critical intellectual issue

How Personality Became Treatable:The Mutual Constitution of Clinical Knowledge and Mental Health Law

In recent years, personality disorders – psychiatric constructs understood as enduring dysfunctions of personality – have come into ever-greater focus for British policymakers, mental health professionals and service-users. Disputes have focussed largely on highly controversial attempts by the UK Department of Health to introduce mental health law and policy (now enshrined within the 2007 Mental Health Act of England and Wales). At the same time, clinical framings of personality disorder have dramatically shifted: once regarded as untreatable conditions, severe personality disorders are today thought of by many clinicians to be responsive to psychiatric and psychological intervention. In this article, I chart this transformation by means of a diachronic analysis of debates and institutional shifts pertaining to both attempts to change the law, and understandings of personality disorder. In so doing, I show how mental health policy and practice have mutually constituted one another, such that the aims of clinicians and policymakers have come to be closely aligned. I argue that it is precisely through these reciprocally constitutive processes that the profound reconfiguration of personality disorder from being an obdurate to a plastic condition has occurred; this demonstrates the significance of interactions between law and the health professions in shaping not only the State’s management of pathology, but also perceptions of its very nature

Who are these youths? Language in the service of policy

In the 1990s policy relating to children and young people who offend developed as a result of the interplay of political imperatives and populist demands. The ‘responsibilisation’ of young offenders and the ‘no excuses’ culture of youth justice have been ‘marketed’ through a discourse which evidences linguistic changes. This article focuses on one particular area of policy change, that relating to the prosecutorial decision, to show how particular images of children were both reflected and constructed through a changing selection of words to describe the non-adult suspect and offender. In such minutiae of discourse can be found not only the signifiers of public attitudinal and policy change but also the means by which undesirable policy developments can be challenged

Quantifying the relationship and contribution of mitochondrial respiration to systemic exercise limitation in heart failure

Aims: Heart failure with reduced ejection fraction (HFrEF) induces skeletal muscle mitochondrial abnormalities that contribute to exercise limitation; however, specific mitochondrial therapeutic targets remain poorly established. This study quantified the relationship and contribution of distinct mitochondrial respiratory states to prognostic whole‐body measures of exercise limitation in HFrEF. Methods and results: Male patients with HFrEF (n = 22) were prospectively enrolled and underwent ramp‐incremental cycle ergometry cardiopulmonary exercise testing to determine exercise variables including peak pulmonary oxygen uptake (V̇O2peak), lactate threshold (V̇O2LT), the ventilatory equivalent for carbon dioxide (V̇E/V̇CO2LT), peak circulatory power (CircPpeak), and peak oxygen pulse. Pectoralis major was biopsied for assessment of in situ mitochondrial respiration. All mitochondrial states including complexes I, II, and IV and electron transport system (ETS) capacity correlated with V̇O2peak (r = 0.40–0.64; P < 0.05), V̇O2LT (r = 0.52–0.72; P < 0.05), and CircPpeak (r = 0.42–0.60; P < 0.05). Multiple regression analysis revealed that combining age, haemoglobin, and left ventricular ejection fraction with ETS capacity could explain 52% of the variability in V̇O2peak and 80% of the variability in V̇O2LT, respectively, with ETS capacity (P = 0.04) and complex I (P = 0.01) the only significant contributors in the model. Conclusions: Mitochondrial respiratory states from skeletal muscle biopsies of patients with HFrEF were independently correlated to established non‐invasive prognostic cycle ergometry cardiopulmonary exercise testing indices including V̇O2peak, V̇O2LT, and CircPpeak. When combined with baseline patient characteristics, over 50% of the variability in V̇O2peak could be explained by the mitochondrial ETS capacity. These data provide optimized mitochondrial targets that may attenuate exercise limitations in HFrEF