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LOCAL LIMIT THEOREMS FOR THE RANDOM CONDUCTANCE MODEL AND APPLICATIONS TO THE GINZBURG-LANDAU ∇Ø INTERFACE MODEL
No full textWarm versus cold cardioplegia in cardiac surgeries: a meta-analysis with trial sequential analysis
No full textObjectiveThis meta-analysis aimed to compare clinical outcomes of warm and cold cardioplegia in cardiac surgeries, with trial sequential analysis used to determine the conclusiveness of the results.MethodsElectronic searches were performed on PubMed, Medline, Scopus, EMBASE and Cochrane library to identify all studies that compared warm and cold cardioplegia in cardiac surgeries. Primary endpoints were in-hospital or 30-day mortality, myocardial infarction (MI), low cardiac output syndrome (LCOS), intra-aortic balloon pump (IABP) use, stroke, and new atrial fibrillation (AF). Secondary endpoints were acute kidney injury (AKI), hospital length of stay (LOS), intensive care unit length of stay (ICU LOS), aortic cross-clamp (ACx) time and cardiopulmonary bypass (CPB) time. Pre-specified subgroup analysis were performed for (1) studies published since publication of Fan et al in 2010 1, (2) studies with low risk of bias, (3) coronary artery bypass graft (CABG) surgeries, and (4) studies with cold blood versus those with cold crystalloid cardioplegia. Trial sequential analysis (TSA) was performed to determine conclusiveness of the results, using on all outcomes without significant heterogeneity from studies of low risk of bias. ResultsNo significant differences were found between post-operative rates of mortality, MI, LCOS, IABP use, stroke, new AF, and AKI between warm and cold cardioplegia. TSA concluded that current evidence was sufficient to rule out a 20% relative risk reduction in these outcomes.ConclusionsConcerning safety outcomes, current evidence suggests that the choice between warm and cold cardioplegia remains in the surgeon’s preference.<br/
Revascularisation strategies in patients with significant left main coronary disease during the COVID-19 pandemic
No full textBackground: There are limited data on the impact of the COVID-19 pandemic on left main (LM) coronary revascularisation activity, choice of revascularisation strategy and post-procedural outcomes.Methods: All patients with LM disease (≥50% stenosis) undergoing coronary revascularisation in England between 01/01/2017 and 19/8/2020 were included (n=22,235), stratified by time-period (pre-COVID: 01/01/2017-29/2/2020; COVID: 1/3/2020-19/8/2020) and revascularisation strategy (percutaneous coronary intervention (PCI) vs. coronary artery bypass grafting (CABG). Logistic regression models were performed to examine odds ratio (OR) of 1) receipt of CABG (vs. PCI) and 2) in-hospital and 30-day postprocedural mortality, in the COVID-19 period (vs. pre-COVID).Results: There was a decline of 1,354 LM revascularisation procedures between 1st March and 31st July 2020 compared with previous years’ (2017-2019) averages (-48.8%). An increased utilisation of PCI over CABG was observed in the COVID period (receipt of CABG vs. PCI: OR 0.46 [0.39, 0.53] compared with 2017), consistent across all age groups. No difference in adjusted in-hospital or 30-day mortality was observed between pre-COVID and COVID periods for both PCI (odds ratio (OR): 0.72 [0.51. 1.02] and 0.83 [0.62, 1.11], respectively) and CABG (OR 0.98 [0.45, 2.14] and 1.51 [0.77, 2.98], respectively) groups.Conclusion: LM revascularisation activity has significantly declined during the COVID period, with a shift towards PCI as the preferred strategy. Postprocedural mortality within each revascularisation group was similar in the pre-COVID and COVID periods, reflecting maintenance in quality of outcomes during the pandemic. Future measures are required to safely restore LM revascularisation activity to pre-COVID levels. <br/
EULAR Points to Consider (PtC) for designing, analysing and reporting of studies with work participation as an outcome domain in patients with inflammatory arthritis
No full textBackground:Clinical studies with work participation as an outcome domain pose particular methodological challenges that hamper interpretation, comparison between studies and meta-analyses.Objectives: To develop points to consider (PtC) for design, analysis and reporting of studies of patients with inflammatory arthritis that include work participation as a primary or secondary outcome domain.Methods:The EULAR Standardized Operating Procedures were followed. A multidisciplinary taskforce with 22 experts including patients with rheumatic diseases, from 10 EULAR countries and Canada, identified methodologic areas of concern. Two systematic literature reviews (SLR) appraised themethodology across these areas. In parallel, two surveys among professional societies and experts outside the taskforce sought for additional methodological areas or existing conducting/reporting recommendations. The taskforce formulated the PtC after presentation of the SLRs and survey results, and discussion. Consensus was obtained through informal voting, with levels of agreement obtained anonymously.Results:Two overarching principles and nine PtC were formulated. The taskforce recommends to align the work-related study objective to the design, duration, and outcome domains/measurement instruments of the study (PtC:1-3); to identify contextual factors upfront and account for them inanalyses (PtC:4); to account for interdependence of different work outcome domains and for changes in work status over time (PtC:5-7); to present results as means as well as proportions of patients reaching predefined meaningful categories (PtC:8); and to explicitly report volumes ofproductivity loss when costs are an outcome (PtC:9).Conclusion: Adherence to these EULAR PtC will improve the methodological quality of studies evaluating work participation
Stillbirth rates, service outcomes and costs of implementing NHS England’s Saving Babies’ Lives care bundle in maternity units in England: a cohort study
No full textObjective – To assess implementation of the Saving Babies Lives (SBL) Care Bundle, a collection of practice recommendations in four key areas, to reduce stillbirth in England. Design – A retrospective cohort study of 463,630 births in 19 NHS Trusts in England using routinely collected electronic data supplemented with case note audit (n=1,658), and surveys of service users (n=2,085) and health care professionals (n=1,064). The primary outcome was stillbirth rate. Outcome rates two years before and after the nominal SBL implementation date were derived as a measure of change over the implementation period. Data were collected on secondary outcomes and process outcomes which reflected implementation of the SBL care bundle. Results - The total stillbirth rate, declined from 4.2 to 3.4 per 1,000 births between the two time points (adjusted Relative Risk (aRR) 0.80, 95% Confidence Interval (95% CI) 0.70 to 0.91, P<0.001). There was a contemporaneous increase in induction of labour (aRR 1.20 (95%CI 1.18- 1.21), p<0.001) and emergency Caesarean section (aRR 1.10 (95%CI 1.07-1.12), p<0.001). The number of ultrasound scans performed (aRR 1.25 (95%CI 1.21-1.28), p<0.001) and the proportion of small for gestational age infants detected (aRR 1.59 (95%CI 1.32-1.92), p<0.001) also increased. Organisations reporting higher levels of implementation had improvements in process measures in all elements of the care bundle. An economic analysis estimated the cost of implementing the care bundle at ~£140 per birth. However, neither the costs nor changes in outcomes could be definitively attributed to implementation of the SBL care bundle. Conclusions – Implementation of the SBL care bundle increased over time in the majority of sites. Implementation was associated with improvements in process outcomes. The reduction in stillbirth rates in participating sites exceeded that reported nationally in the same timeframe. The intervention should be refined to identify women who are most likely to benefit and minimise unwarranted interventio
Effect of stress and surface finish on Pb-caustic SCC of Alloy 690TT
No full textThe effect of surface preparation on lead-induced stress corrosion cracking (PbSCC) of Alloy 690TT in Pb-caustic solution was investigated using C-rings manufactured from tubing that was either as-manufactured or polished. The surface deformed layer on the as-manufactured samples promoted the formation of an oxide, which reduced the number of sites for crack nucleation. Conversely, the polished surface developed crystallographic corrosion slots from which some of the cracks seemed to initiate. Advanced microstructural characterization complemented with stress analysis of the samples, suggested that the early stages of PbSCC are consistent with a film-rupture/slip-dissolution mechanism and influenced by de-alloying
The Alliance-Outcome Relationship in Individual Psychosocial Treatment for Schizophrenia and Early Psychosis:A Meta-Analysis
No full textThe therapeutic alliance, or client-provider relationship, has been associated with better treatment engagement and outcomes for persons with schizophrenia-spectrum disorders (SSDs) and early psychosis in some studies, but not others. We conducted a meta-analysis of the research on alliance in SSDs and early psychosis across a range of interventions and outcomes. Parallel literature searches were conducted in PubMed and PsycINFO databases for articles between inception and 6/11/2020. English-language studies were included if they evaluated the relationship between alliance and a prospective outcome (treatment engagement, medication adherence, functioning, or total, positive, negative, or depressive symptoms) in an individual clinical treatment for SSDs/early psychosis and contained analyzable data. Correlations and partial correlations were meta-analyzed with random effects models to calculate mean across-study correlations and to carry out subsequent homogeneity and moderator variable analyses. Fourteen studies consisting of 2,968 participants that assessed six outcomes across six psychosocial treatments were included. Results indicated that better client-rated (r=.20) and other-rated (i.e., provider- or observer-rated; r=.25) alliance were associated with better treatment engagement. Treatment type and sample race/ethnicity, but not age, gender, or timing of alliance rating moderated the association between other-rated alliance and engagement. Further, better other-rated alliance was related to improvements in positive (r=-.14) and negative (r=-.22) symptoms. A strong therapeutic alliance is important for both engaging clients with SSDs and early psychosis in treatment and facilitating improvements in positive and negative symptoms. Delivery and monitoring of treatments for this population should include assessment of the therapeutic alliance from multiple perspectives
Evidencing the benefits of Industry 4.0 for the Architecture, Engineering and Construction (AEC) Industry: Promises, practices and unresolved problems
No full textPresent status of electric-doublelayer thin-film transistors and their applications
No full textAs thin-film transistors (TFTs) are the workhorse of thin-film electronics, a great deal of focus has been placed upon improving their performance. One major avenue of investigation is the use of electrolyte dielectrics, which can form high capacitance electric-double-layers (EDLs). The high capacitance of the EDL enables low-voltage TFT operation by inducing high carrier densities in the channel at low operating voltages. Moreover, due to the diverse range of electrolyte materials under investigation, many EDL TFTs meet the requirements for use in flexible and printable electronics. Here, the basic principles of TFTs and EDLs are introduced along with the advantages and disadvantages of different types of electrolytes. The present status of EDL TFTs is assessed with respect to different channel materials, e.g. oxide semiconductors and organic semiconductors. An overview of the potential uses of EDL is also given, including research into insulator to metal and insulator to superconductor transitions as well as incorporation into both chemical and thermal sensors. Beyond the basic EDL TFT building blocks, logic circuits for low-power electronic devices, such as memories, sensors, and neuromorphic circuits which take advantage of the unusual properties of the EDL to mimic neural networks, are also summarized. Finally, the outlook and challenges for EDL TFTs are discussed
Integrating Formal Verification and Assurance:An Inspection Rover Case Study
No full textThe complexity and flexibility of autonomous robotic systems necessitates a range of distinct verification tools. This presents new challenges not only for design verification but also for assurance approaches. Combining the distinct formal verification tools, while maintaining sufficient formal coherence to provide compelling assurance evidence is difficult, often being abandoned for less formal approaches. In this paper we demonstrate, through a case study, how a variety of distinct formal techniques can be brought together in order to develop a justifiable assurance case. We use the AdvoCATE assurance case tool to guide our analyses and to integrate the artifacts from the formal methods that we use, namely: fret, cocosim and Event-B. While we present our methodology as applied to a specific Inspection Rover case study, we believe that this combination provides benefits in maintaining coherent formal links across development and assurance processes for a wide range of autonomous robotic systems