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Finite element modelling of hot compression testing of titanium alloys
No full textThis paper presents experimental results and finite element analysis of hot upsetting of titanium alloys Ti64 and Ti407 using a dilatometer in loading mode. All samples showed barrelling, as a consequence of an inhomogeneous temperature distribution and friction. The FE analysis is a full thermomechanical model of the test calibrated using multiple thermocouples. At each nominal temperature and strain-rate, the true flow stress-strain response is inferred using the difference between the initially assumed constitutive response input to the FE analysis, 𝜎𝜎=𝑓𝑓(𝑇𝑇,𝜀𝜀˙,𝜀𝜀), and the predicted response of the model. The analysis applies new procedures for: (i) modelling the thermal gradient; (ii) finding the flow stress correction due to the inhomogeneity, using literature data as the input to the FE analysis; (iii) smoothing the constitutive data, fitting empirical 𝜎𝜎=𝑓𝑓(𝑇𝑇,𝜀𝜀˙) surfaces at multiple discrete strains. The extracted true constitutive data confirms the moderate strain-softening behaviour in Ti64 alloy, and the FE model predicts the distribution of local deformation conditions, for application in interpretation of microstructure and texture evolution. This highlights the difference between nominal and actual test conditions, showing that the discrepancy varies systematically with test conditions, with the central strain and strain-rate being magnified significantly, by factors of order 2–3
Characterisation of Ferritic to Austenitic Steel Functional Grading via Powder Hot Isostatic Pressing
No full textThe application of functionally graded components produced via the powder hot isostatic pressing (HIP) process is considered for the next generation nuclear reactors as an alternative to dissimilar metal welding. This work is focused on functional grading of an SA508 Grade 3 ferritic low-alloy steel and 316L austenitic stainless steel, typically present in the pressure vessel and the piping or the pressure vessel cladding, respectively. Material was supplied in powder form, mixed and consolidated via the HIP process. Five different powder fractions were studied and, in some cases, significant change in the ferrite over austenite ratio is found to take place, due to dilution of austenite stabilizing elements. In contrast, the enrichment of alloying elements within the ferritic phase promotes the formation of laths, greatly affecting the material properties. The strengthening effect of the ferritic lath zone is assessed and the mechanism for its formation in the ferritic-austenitic system studied (throughout this work the term ferritic laths refers to a ferritic phase of unknown structure which is likely to consist of martensite, bainite or a mixture of both).KeywordsHot isostatic pressing, Functional grading, SA508, 316
ENVIRONMENTAL SUSTAINABILITY PERFORMANCE OF A MEMBRANE-BASED TECHNOLOGY FOR LIVESTOCK WASTEWATER TREATMENT WITH NUTRIENT RECOVERY
No full textThe gas-permeable membrane (GPM) technology is one of the most novel techniques capable of minimizing ammonia (NH3) emissions associated to wastewaters, while recovering nitrogen as nutrient. This study conducted for the first time a life cycle assessment of this technology (treatment scenario), to compare the environmental trade-offs with the conventional manure management (conventional scenario), and determine which strategy performs better. The environmental impact results per m3 of manure, estimated using the ReCiPe method V 1.1, indicated that the treatment scenario reduces global warming (GW) by 14% and marine eutrophication (ME) by 32% with respect to the conventional scenario, whilst it increases particulate matter formation (PMF) and terrestrial acidification (TA) by 16% and 17%, respectively, due to some NH3 volatilization. Other impact categories considered were ozone formation (affecting human health (HOF) and ecosystems (EOF)), where the treatment scenario was able to reduce this impact by 48% and 50%, respectively. For freshwater eutrophication (FE), the net value was similar for both scenarios. A sensitivity analysis looking at optimum membrane design parameters (optimized treatment scenario) resulted in further reductions between 26% and 86% for GW, ME, PMF and TA with respect to the conventional scenario, although one potential drawback is the application of higher amount of phosphorous with the organic fertilizer, which resulted in higher FE impacts. Overall, the GPM system-based treatment is more environmentally sustainable compared to the conventional scenario thus making this an attractive option for environmental management systems, especially in areas with low water quality or high nutrient imbalance. Keywords: Life cycle assessment, manure treatment, ammonia reduction, nutrient imbalance, agricultural effluents.<br/
Affective Human-Robot Interaction with Multimodal Explanations
No full textFacial expressions are one of the most practical and straightforward ways to communicate emotions. Facial Expression Recognition has been used in lots of fields such as human behaviour understanding and health monitoring. Deep learning models can achieve excellent performance in facial expression recognition tasks. As these deep neural networks have very complex nonlinear structures, when the model makes a prediction, it is not easy for human users to understand what is the basis for the model’s prediction. Specifically, we do not know which facial units contribute to the classification more or less. Developing affective computing models with more explainable and transparent feedback for human interactors is essential for a trustworthy human-robot interaction. Comparing to “white-box” approaches, “black-box” approaches using deep neural networks, which have advantages in terms of overall accuracy but lack reliability and explainability. In this work, we introduce a multimodal affective human-robot interaction framework, with visualbased and verbal-based explanation, by Layer Wise Relevance Propagation (LRP) and Local Intepretable Mode-Agnostic Explanation (LIME). The proposed framework has been tested on the KDEF dataset, and in human-robot interaction experiments with the Pepper robot. This experimental evaluation shows the benefits of linking deep learning emotion recognition systems with explainable strategies
Genetically proxied TYK2 inhibition is associated with reduced sarcoidosis susceptibility
No full textCurrent insights into skin lipids and their roles in cutaneous health and disease
No full textPurpose of review: The unique and complex array of cutaneous lipids include essential components of the skin structure and signalling molecules mediating homeostasis and inflammation. Understanding skin lipid biology and metabolism can support our comprehension of health and disease, including systemic conditions with cutaneous involvement. Recent findings: Lipids found on the skin surface, produced by both the host and resident microbes, maintain and regulate the skin microbiome and the epidermal barrier, whilst altered contributions from either source can be detrimental to skin health. The unique lipid composition of the epidermal barrier is essential for its function, and recent studies have expanded our understanding of epidermal ceramide production. This has been supported by improved models available for skin research, including organotypic skin models enabling in vitro production of complex acylceramides for the first time, and model systems facilitating in silico exploration of the lipid profile changes observed in clinical samples. Studies have revealed further involvement of lipid mediators such as eicosanoids in cutaneous inflammation, as well as immune regulation in both healthy and diseased skin.Summary: Skin lipids offer exciting opportunities as therapeutic targets for many conditions, whether through topical interventions or nutritional supplementation.<br/
Guideline adherence predicts Survival of Candidemia in Europe: Results from the ECMM Candida III multinational European Cohort Study
No full textBackgroundThe European Confederation of Medical Mycology (ECMM) collected data on epidemiology, risk factors, treatment, and outcomes of culture proven candidemia across Europe in order to assess how adherence to guideline recommendations correlate with outcomes.MethodsEach participating hospital (number of eligible hospitals per country determined by population size) included the first ~10 culture proven candidemia cases after 01-July-2018 and entered data into the ECMM Candida III database on the FungiScope® platform. EQUAL Candida Scores reflecting adherence to recommendations of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and Infectious Disease Society of America (IDSA) Guidelines were assessed.FindingsA total of 632 candidemia cases were included from 60 institutions in 20 European countries. Overall mortality was 46.4% (286/617), and older age, intensive care unit (ICU) admission and rare Candida spp. as causative pathogens were independent predictors of mortality in Cox regression analysis. EQUAL Candida Score was evaluable for 589 cases with candidemia and remained an independent predictor of mortality in the multivariable Cox regression analyses after adjusting for age, ICU admission and rare Candida spp. (adjusted hazard ratios between 1.074 and 1.087 per 1 point decrease; pInterpretationWhile overall mortality of candidemia was 46%, our study indicates that adherence to clinical guideline recommendations, reflected by higher EQUAL Candida Scores, may increase survival. Echinocandin treatment was associated with increased overall survival, but also longer duration of hospitalization (hospitalization was prolonged only for completing treatment in 16%).<br/
A genome-wide association study with tissue transcriptomics identifies genetic drivers for classic bladder exstrophy
No full textClassic bladder exstrophy represents the most severe end of all human congenital anomalies of the kidney and urinary tract and is associated with bladder cancer susceptibility. Previous genetic studies identified one locus to be involved in classic bladder exstrophy, but were limited to a restrict number of cohort. Here we show the largest classic bladder exstrophy genome-wide association analysis to date where we identify eight genome-wide significant loci, seven of which are novel. In these regions reside ten coding and four non-coding genes. Among the coding genes is EFNA1, strongly expressed in mouse embryonic genital tubercle, urethra, and primitive bladder. Re-sequence of EFNA1 in the investigated classic bladder exstrophy cohort of our study displays an enrichment of rare protein altering variants. We show that all coding genes are expressed and/or significantly regulated in both mouse and human embryonic developmental bladder stages. Furthermore, nine of the coding genes residing in the regions of genome-wide significance are differentially expressed in bladder cancers. Our data suggest genetic drivers for classic bladder exstrophy, as well as a possible role for these drivers to relevant bladder cancer susceptibility
Differences in walking football initiation and maintenance influences across respondent characteristics: a cross-sectional survey in 50-75 year -old adults
No full textDespite health benefits gained from physical activity and sport participation, older adults are less likely to be active. This study investigates what influences 50–75-year-olds (N=439) to initiate and maintain walking football, across gender, socioeconomic status, number of health conditions and physical activity level. It also considers relationships between participant characteristics and influences, and intentions to play after a forced break (COVID-19). Results of a UK online cross-sectional survey found those with two or more health conditions rated social influences significantly higher in initiation and maintenance, than participants with no health conditions. Multiple regression analysis found a positive walking football culture and perceived use of maintenance resources contributed significantly to intentions to return to play after COVID-19 restrictions eased. Practitioners should consider providing opportunities for social connection, foster a positive walking football culture, and encourage players to utilise maintenance resources (e.g., scheduling sessions) in older adult walking football sessions.Keywords: behaviour change, soccer, physical activity, survey research, older adults<br/
Making History Together: The UK’s National Health Service and the story of our lives since 1948
No full textOnly since the 2010s have historians become interested in dimensions of the UK’s National Health Service (NHS) histories beyond institutional, policy, and political narratives and the seventieth anniversary of the Service in 2018 gave additional impetus to work in this area. This paper argues for the need for a new interpretative framework for NHS histories that better reflects its multiple identities and social meanings. Drawing on a UK-wide programme of work it explores the processes of creating digital archive of NHS history using concepts and methodologies that foreground the institution’s social and dynamic nature and are underpinned by a commitment to inclusivity of perspectives and actors. It considers the challenges of working across academic, health, and heritage sectors and the need for historians to adapt to sharing power and agency when working alongside volunteers and interviewees. It concludes that the history produced through these ways of working is rich and insightful and has the potential to reshape historical practice and scholarship around NHS histories and beyond