Computational modelling of inertia friction welding

This study details the development and validation of a finite element methodology to robustly simulate the inertia friction welding (IFW) process. There are many difficulties involved in modelling IFW. These include the short and violent process to complete a weld, as well as the challenges in obtaining experimental data throughout the process to complement, validate and inform the modelling effort. The objectives here are to model the macroscale multiphysical process leading to an accurate prediction of key process output variables, ultimately leading to a reliable method for predicting the post weld microstructure

Fabrication of a compliant phantom of the human aortic arch for use in Particle Image Velocimetry (PIV) experimentation

Compliant phantoms of the human aortic arch can mimic patient specific cardiovascular dysfunctions in vitro. Hence, phantoms may enable elucidation of haemodynamic disturbances caused by aortic dysfunction. This paper describes the fabrication of a thin-walled silicone phantom of the human ascending aorta and brachiocephalic artery. The model geometry was determined via a meta-analysis and modelled in SolidWorks before 3D printing. The solid model surface was smoothed and scanned with a 3D scanner. An offset outer mould was milled from Ebalta S-Model board. The final phantom indicated that ABS was a suitable material for the internal model, the Ebalta S-Model board yielded a rough external surface. Co-location of the moulds during silicone pour was insufficient to enable consistent wall thickness. The resulting phantom was free of air bubbles but did not have the desired wall thickness consistency

The effects of Covid-19 lockdown on health and psychosocial functioning in older adults aged 70 and over

The COVID-19 pandemic led to a state-imposed lockdown in the UK; there are many psychosocial consequences of pandemics, with older adults potentially at an increased risk. The current study assessed psychosocial functioning in a sample of older adults in the UK with baseline data collected pre-lockdown and follow-up 12 weeks later during lockdown. Thus, allowing investigation of the effect of COVID-19 and associated lockdown on psychosocial well-being. Thirty-five older adults (Mean age = 76.06, sex = 12 males) participated in this repeated measures study. A final follow-up was then conducted post-lockdown to capture any factors that were viewed as helpful to well-being during lockdown. From pre- to during lockdown, perceived stress, well-being, depressive symptoms, mood disturbance and memory were all significantly worsened. There were significant improvements in self-reported physical health symptoms, social interaction, time spent engaging in physical activity and certain aspects of relationship quality. Follow-up showed that well-being, depression and mood were still negatively affected post-lockdown. Given the sample were all ‘healthy’ at baseline in comparison to established norms, there may be greater impairment in more vulnerable populations. Support for older populations is needed to mitigate the negative effects shown, particularly in light of the endurance of some of these effects post-lockdown

A Novel Fabrication Method for Compliant Silicone Phantoms of Arterial Geometry for Use in Particle Image Velocimetry of Haemodynamics

Cardiovascular diseases (CVDs) are one of the leading causes of death globally. In-vitro measurement of blood flow in compliant arterial phantoms can provide better insight into haemodynamic states and therapeutic procedures. However, current fabrication techniques are not capable of producing thin-walled compliant phantoms of complex shapes. This study presents a new approach for the fabrication of compliant phantoms suitable for optical measurement. Two 1.5× scaled models of the ascending aorta, including the brachiocephalic artery (BCA), were fabricated from silicone elastomer Sylgard-184. The initial phantom used the existing state of the art lost core manufacturing technique with simple end supports, an acrylonitrile butadiene styrene (ABS) additive manufactured male mould and Ebalta-milled female mould. The second phantom was produced with the same method but used more rigid end supports and ABS male and female moulds. The wall thickness consistency and quality of resulting stereoscopic particle image velocimetry (SPIV) were used to verify the fidelity of the phantom for optical measurement and investigation of physiological flow fields. However, the initial phantom had a rough surface that obscured SPIV analysis and had a variable wall thickness (range = 0.815 mm). The second phantom provided clear particle images and had a less variable wall thickness (range = 0.317 mm). The manufacturing method developed is suitable for fast and cost-effective fabrication of different compliant arterial phantom geometries

Cardiovascular, mortality and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: a systematic review and meta-analysis of cardiovascular outcome trials

Background: Glucagon-like peptide-1 (GLP-1) receptor agonists differ in their structure and duration of action and have been studied in trials of varying sizes and with different patient populations, with inconsistent effects on cardiovascular outcomes reported. We aimed to synthesise the available evidence by doing a systematic review and meta-analysis of cardiovascular outcome trials of these drugs. Methods: We searched MEDLINE (via PubMed) and the Cochrane Central Register of Controlled Trials for eligible placebo-controlled trials reporting major adverse cardiovascular events (MACE; ie, cardiovascular death, stroke, or myocardial infarction) up to June 15, 2019. We did a meta-analysis using a random-effects model to estimate overall hazard ratios (HRs) for MACE, its components, death from any cause, hospital admission for heart failure, kidney outcomes, and key safety outcomes (severe hypoglycaemia, pancreatitis, and pancreatic cancer). We also examined MACE in several subgroups based on patient characteristics (history of cardiovascular disease, BMI, age, baseline HbA1c, and baseline estimated glomerular filtration rate), trial duration, treatment dosing interval, and structural homology. Findings: Of 27 publications screened, seven trials, with a combined total of 56 004 participants, were included: ELIXA (lixisenatide), LEADER (liraglutide), SUSTAIN-6 (semaglutide), EXSCEL (exenatide), Harmony Outcomes (albiglutide), REWIND (dulaglutide), and PIONEER 6 (oral semaglutide). Overall, GLP-1 receptor agonist treatment reduced MACE by 12% (HR 0·88, 95% CI 0·82–0·94; p<0·0001). There was no statistically significant heterogeneity across the subgroups examined. HRs were 0·88 (95% CI 0·81–0·96; p=0·003) for death from cardiovascular causes, 0·84 (0·76–0·93; p<0·0001) for fatal or non-fatal stroke, and 0·91 (0·84–1·00; p=0·043) for fatal or non-fatal myocardial infarction. GLP-1 receptor agonist treatment reduced all-cause mortality by 12% (0·88, 0·83–0·95; p=0·001), hospital admission for heart failure by 9% (0·91, 0·83–0·99; p=0·028), and a broad composite kidney outcome (development of new-onset macroalbuminuria, decline in estimated glomerular filtration rate [or increase in creatinine], progression to end-stage kidney disease, or death attributable to kidney causes) by 17% (0·83, 0·78–0·89; p<0·0001), mainly due to a reduction in urinary albumin excretion. There was no increase in risk of severe hypoglycaemia, pancreatitis, or pancreatic cancer. Interpretation: Treatment with GLP-1 receptor agonists has beneficial effects on cardiovascular, mortality, and kidney outcomes in patients with type 2 diabetes

Early Laser for Burn Scars (ELABS): protocol for a multi-centre randomised, controlled trial of both the effectiveness and cost-effectiveness of the treatment of hypertrophic burn scars with Pulsed Dye Laser and standard care compared to standard care alone [version 1; peer review: 2 approved]

This paper outlines the protocol for a study that is being carried out at multiple centres across the UK in the next three years. It is a Research for Patient Benefit (RfPB) study funded by the National Institute for Healthcare Research (NIHR). The aim is to assess the effectiveness of treating hypertrophic burns scars with pulsed dye laser (PDL) at an early stage of scar formation.  The objective is to improve Quality of Life for the patient by improving both the appearance and quality of burn scarring, as well as reducing its psychological impact. This is a parallel-arm randomised, controlled trial to compare PDL and standard care against standard care alone.  The difference is measured between baseline and six-month follow-up. Recruits are within three months of healing from a burn injury; with wounds showing a defined potential for hypertrophic scarring. A total of 120 patients are recruited in a multi-centre study; with randomisation in a 1:1 allocation to each arm.  The treatment arm receives 3 PDL treatments at six-week intervals in addition to standard care, whereas the control arm receives standard care alone.  The primary outcome is the patient-rated part of the Patient and Observer Scar Scale (POSAS).  Psychological and psycho-social impact is evaluated using the CARe burn scale (UWE, Bristol) and Quality Adjusted Life Years (QALY) is determined using the Short-Form Health Survey (SF-12). The study evaluates both the cost-effectiveness through an economic analysis and the patient-reported experience of the treatment by phone interviews. Trial registration: ISRCTN14392301 (registered on 14th June 2021) Contact for Public & Scientific Queries: Mark Brewin, [email protected]   Public Title: Early Laser for Burn Scars (ELABS): a trial of the effectiveness and cost of the treatment of hypertrophic burn scars with laser Countries of Recruitment: England & Scotland Protocol Version: v11, October 202

In-vitro particle image velocimetry assessment of the endovascular haemodynamic features distal of stent-grafts that are associated with development of limb occlusion

Aneurysms are common vascular diseases which affect normal haemodynamics in the aorta. Endovascular aortic repair (EVAR) using stent-grafts is a common treatment that excludes the aneurysm from the circulation, preventing further growth and eventual rupture. However, complications such as endoleak, dislocation or limb occlusion have been reported after EVAR. This study hypothesized that the compliance mismatch between the graft and parent artery causes haemodynamic disturbances at the distal edge of the graft. Therefore, the potential for the graft to cause limb occlusion was assessed. A compliant phantom was fabricated. A circulatory loop was developed to run the fluid and generate a physiological flow waveform. Particle Image Velocimetry was utilised to capture fluid dynamics in the replica. The result showed a low velocity region at the graft trailing edge wall. The low velocity boundary layer thickness decreased downstream of the graft. A flow recirculation was initiated and increased in size during the mid-acceleration at the low velocity region. Shear stresses fluctuated at the trailing edge of the graft which is a risk factor for intimal thickening followed by graft or limb occlusion. It was concluded that this haemodynamic behaviour was due to the graft and parent artery compliance mismatch

Risks, reflection, rewards, and resistance: academic perspectives on creative pedagogies for active learning

In recent decades there has been a paradigmatic shift in higher education towards active learning, requiring educators to adopt student-centred approaches to teaching to promote deep learning and the development of essential graduate attributes. A ‘Creative pedagogies for active learning’ course was designed to offer academic staff an opportunity to take risks in developing innovative student-centred teaching approaches. While participants encountered ‘dissonance’ during the early stages of the creative pedagogies course, the course leads were able to support participants through this period of uncertainty and risk-taking towards successfully disrupting their own teaching practice. This reflective analysis paper outlines the course and showcases several case studies of practice by participants. We also reflect on their experiences through a subsequent roundtable discussion. This revealed that the course had made a longer-term impact on some participants in terms of their teaching and assessment practice and showcasing this to other educators. However, resistance to change in some departments was noted, making it difficult for staff to implement creative pedagogies more widely in practice. Suggestions for overcoming resistance are presented, and the paper concludes with future directions for taking this work forward

Early Laser for Burn Scars (ELABS): protocol for a multi-centre randomised, controlled trial of both the effectiveness and cost-effectiveness of the treatment of hypertrophic burn scars with Pulsed Dye Laser and standard care compared to standard care alone [version 1; peer review: 2 approved].

This paper outlines the protocol for a study that is being carried out at multiple centres across the UK in the next three years. It is a Research for Patient Benefit (RfPB) study funded by the National Institute for Healthcare Research (NIHR). The aim is to assess the effectiveness of treating hypertrophic burns scars with pulsed dye laser (PDL) at an early stage of scar formation. The objective is to improve Quality of Life for the patient by improving both the appearance and quality of burn scarring, as well as reducing its psychological impact. This is a parallel-arm randomised, controlled trial to compare PDL and standard care against standard care alone. The difference is measured between baseline and six-month follow-up. Recruits are within three months of healing from a burn injury; with wounds showing a defined potential for hypertrophic scarring. A total of 120 patients are recruited in a multi-centre study; with randomisation in a 1:1 allocation to each arm. The treatment arm receives 3 PDL treatments at six-week intervals in addition to standard care, whereas the control arm receives standard care alone. The primary outcome is the patient-rated part of the Patient and Observer Scar Scale (POSAS). Psychological and psycho-social impact is evaluated using the CARe burn scale (UWE, Bristol) and Quality Adjusted Life Years (QALY) is determined using the Short-Form Health Survey (SF-12). The study evaluates both the cost-effectiveness through an economic analysis and the patient-reported experience of the treatment by phone interviews

Cohort profile : early pandemic evaluation and enhanced surveillance of COVID-19 (EAVE II) database

Funding: The original EAVE project was funded by the National Institute for Health Research Health Technology Assessment Programme (project number 13/34/14). EAVE II is funded by the Medical Research Council [MR/R008345/1] and supported by the Scottish Government. This work is supported by BREATHE - The Health Data Research Hub for Respiratory Health [MC_PC_19004]. BREATHE is funded through the UK Research and Innovation Industrial Strategy Challenge Fund and delivered through Health Data Research UK.PostprintPeer reviewe