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Maintaining tight mechanical tolerances of the components used in helical flux compression generators is crucial for optimizing device performance. Moving beyond current literature, which provides various approximations for acceptable tolerances, a 3D simulation of the armature stator interaction during generator operation was developed, revealing that existing equations frequently misestimate the tolerance limits. Without restricting the generality of the presented approach, the focus was primarily on the armature’s concentricity and roundness, comparing the acceptable tolerance limits between generators of different sizes. An analytical approach for select geometries was developed, confirming the 3D results. Quantitative results reveal that a steeper Gurney angle and increased winding pitch allow for less restrictive tolerances for eccentricity and ellipticity. Even small deviations from the ideal armature positioning and shape will result in fluctuations of the output current time-derivative, observed experimentally and in simulation. Larger deviations then cause partial turn skipping, associated with loss of magnetic flux. The simulation elucidates the impact of tolerance deviations on generator performance by offering precise tolerance ranges for various generator sizes, thereby facilitating informed design decisions.

A comparative analysis of the attachment efficacy of sharpened vs blunted air terminals under a strong background DC electric field, similar to conditions found in naturally occurring lightning events, is presented. Testing was conducted using an oil-free, 17-stage, 1.4 MV bipolar Marx generator with a biased discharge plane that emulated the conditions found prior to the lightning return stroke. The biased discharge plane allowed the introduction of a strong DC electric field and subsequent corona formation on a time scale much longer than the brief duration over which the downward leader propagates. Initial observations indicate that despite a higher background electric field at the sharpened terminals, leading to pre-discharge corona formation where none is seen on the blunt terminal, both the sharpened and blunted terminals exhibit similar attachment probabilities during discharge events, with some discharge events attaching to both terminals.

The recent trends of vitrimer studies enhance the thermoset material with superior properties, therefore, it is particularly important to address the critical scientific inquiries in this area using their research metrics. The reported vitrimer systems have been highly required for future real-time applications; however, the inquisitiveness of material exchange mechanisms extends the research studies further. Significantly, more scientific information's are required to achieve the evident prospective outcomes via these materials. This article highlights the trends and developments of the most relevant publications, authors, articles, countries, and keywords in the vitrimer research field over the past 10 years. The represented bibliometric survey would elevate the basic understanding of the current vitrimer research stats and also help follow the particular research community to learn and develop insight. To generate bibliometric networks, bibliometric data has obtained from Scopus and visualised in VOS-viewer; as an overview of that, the highest number of publications were from China, United States, France, United Kingdom, and Spain.

Objective: To perform a systematic review and meta-analysis to compare the results of the Latarjet procedure performed using screws (S) or suture-button for coracoid graft fixation., Methods: A systematic search in Pubmed, EMBASE, and The Cochrane Library databases was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Cohort studies comparing outcomes in the Latarjet procedure with screw fixation versus the Latarjet procedure with suture-button fixation were included., Results: Five studies with 877 patients were included. There was a significantly lower rate of recurrent instability in those with S fixation compared to the suture-button fixation (1.5% vs 5%, p  = 0.001). There was a significantly higher rate of reoperations with S fixation compared to suture-button fixation (4.3% vs 0%, p  = 0.001). There were no significant differences between the groups regarding total complications (S: 7.5% vs suture-button: 3.6% p  = 0.12) graft fracture (S: 0.8% vs suture-button: 0.5% p  = 0.62) and symptomatic hardware (S: 2.7% vs suture-button: 0% p  = 0.12)., Conclusion: The Latarjet surgery was associated with favorable results and a low rate of complications regardless of the type of fixation used. Screw fixation was associated with a significantly lower rate of recurrences, but greater reoperations due to irritation or pain after surgery., Level of Evidence: Systematic review and meta-analysis, level III., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. The category in which the manuscript is being submitted is Systematic review—meta-analysis. The paper is not based on a previous communication to a society or meeting., (© The Author(s) 2024.)

Multiple pulse charging modules were designed and tested for synchronous use in scaled experiments. The pulse chargers are each capable of charging a nanofarad-sized capacitive load to 100 kV in less than 10 µs. This is achieved by initially charging a microfarad-sized capacitor to a maximum of 3 kV, then, using a thyristor switch, discharging the capacitor into two transformers paralleled on the primary side. Each transformer steps the voltage up to 50 kV, with the transformer having opposing polarities and a common neutral on the secondary. Thus, the full 100 kV is obtained by placing the nanofarad-sized capacitor between the +50 and -50 kV terminals. The pulse chargers use a microcontroller to monitor and control the pulse charger in addition to communicating with the user as well as other pulse chargers. For increased battery life, each pulse charger is kept in a low-power state while not in use. Upon startup, the pulse chargers automatically detect the number of modules in the system, the position of itself in the system, and the timing delays associated with each pulse charger in the system. This information is essential for synchronous charging and provides individual information and controls for the pulse chargers., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Background: Failure rates up to 14% have been reported after arthroscopic posterior capsulolabral repair. It is unknown if revision arthroscopic posterior capsulolabral stabilization has inferior restoration of stability and return to sport when compared with primary repair. Optimal management of failed posterior capsulolabral stabilization is unknown., Purpose: To report outcomes of revision posterior capsulolabral repair and factors that contribute to failure and to determine optimal management of failed posterior stabilization procedures., Study Design: Systematic review; Level of evidence, 4., Methods: A computerized search of the PubMed, EMBASE, and Web of Science databases and manual screening of selected article reference lists were performed in January 2022. Randomized controlled trial, cohort, case-control, and case series studies reporting clinical outcomes of revision arthroscopic posterior capsulolabral repair were eligible. Patient characteristics, indications for revision, intraoperative findings, surgical techniques, and patient-reported outcomes were recorded. Owing to heterogeneity of reported outcomes, data were summarized and presented without pooled statistics., Results: Only 3 of the 990 identified studies met inclusion criteria. The included studies encompassed 26 revision arthroscopic posterior capsulolabral repairs, with follow-up ranging from 2.3 to 5.3 years. The failed index procedure was arthroscopic capsulolabral repair with suture anchors (n = 22) or posterior thermal capsulorrhaphy (n = 4). The primary indications for revision were recurrent instability and pain. Six patients experienced recurrent instability after revision. Patient satisfaction ranged from 15% to 25%., Conclusion: This systematic review of 3 studies demonstrated that the incidence of persistent pain and recurrent instability after revision arthroscopic posterior shoulder stabilization is common, and despite slight improvement in patient-reported outcomes, many patients are dissatisfied with their clinical outcomes. Revision arthroscopic posterior shoulder stabilization appears to have a significant failure rate, and there is need for additional prospective studies to help determine the best intervention for these patients., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: E.B. has received grant support from DJO, education payments from Arthrex and Smith & Nephew, and hospitality payments from Stryker. R.W.W. has received royalties from Responsive Arthroscopy. J.D. has received education payments from Supreme Orthopedic Systems and nonconsulting fees from Arthrex. L.L. has received grant support from DJO and education payments from Arthrex. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2023.)

Background: Local multi-agency case reviews are regularly held in England when children have suffered significant harm from abuse or neglect, including from child sexual abuse (CSA). Most CSA takes place within families, is common but under-reported and can cause long-term harm., Objective: The aim was to analyse English child protection reviews relating to intrafamilial CSA to identify improvements for professional practice., Participants and Setting: Local Child Safeguarding Practice Reviews (LCSPRs) and Serious Case Reviews (SCRs) relating to serious incidents of intrafamilial CSA occurring between 01 April 2017 and 31 March 2020., Methods: LCSPRs and SCRs were obtained from the National Case Review Repository and thematically analysed., Results: There were 243 reviews, of which 25 featured intrafamilial CSA. The main themes related to perpetrators, vulnerable families, and professional practice. Half of perpetrators were known by services to have previously abused children, but issues with professional practice enabled them to continue. Most children did not disclose CSA verbally showing challenging or sexualised behaviour; but professionals lacked knowledge and confidence on how to intervene without verbal disclosure, which limited safeguarding actions. Non-engagement by families with services was common, with some non-abusing parents complicit in abuse and deception. Significant neglect occurred in half the families, which diverted professional attention away from CSA., Conclusion: CSA is deliberate abuse of children involving considerable deception by perpetrators in contrast to some other types of child abuse. This difference in abuser behaviour makes child protection more difficult, particularly when professionals do not recognise and respond to children's non-verbal disclosures., Competing Interests: Declaration of competing interest Dr. Garstang, Professor Dickens and Professor Taylor were all funded by the Department for Education for their analysis of Local Child Safeguarding Practice Reviews and Serious Case Reviews. The funder requested an analysis of intrafamilial CSA in Serious Case Reviews, but had no role in the design, analysis, reporting or decision to publish this paper. Ms. Menka has no declarations of interest to declare., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Endemic Burkitt lymphoma (eBL) is a pediatric cancer coendemic with malaria in sub-Saharan Africa, suggesting an etiological link between them. However, previous cross-sectional studies of limited geographic areas have not found a convincing association. We used spatially detailed data from the Epidemiology of Burkitt Lymphoma in East African Children and Minors (EMBLEM) study to assess this relationship. EMBLEM is a case-control study of eBL from 2010 through 2016 in six regions of Kenya, Uganda, and Tanzania. To measure the intensity of exposure to the malaria parasite, Plasmodium falciparum , among children in these regions, we used high-resolution spatial data from the Malaria Atlas Project to estimate the annual number of P. falciparum infections from 2000 through 2016 for each of 49 districts within the study region. Cumulative P. falciparum exposure, calculated as the sum of annual infections by birth cohort, varied widely, with a median of 47 estimated infections per child by age 10, ranging from 4 to 315 infections. eBL incidence increased 39% for each 100 additional lifetime P. falciparum infections (95% CI: 6.10 to 81.04%) with the risk peaking among children aged 5 to 11 and declining thereafter. Alternative models using estimated annual P. falciparum infections 0 to 10 y before eBL onset were inconclusive, suggesting that eBL risk is a function of cumulative rather than recent cross-sectional exposure. Our findings provide population-level evidence that eBL is a phenotype related to heavy lifetime exposure to P. falciparum malaria and support emphasizing the link between malaria and eBL.

Higher perceived social support has been shown to buffer the impact of negative stressful events like childhood abuse on health outcomes. Yet, the role of perceived social support as a mediator of the association between childhood abuse and pain-related characteristics is not well understood. The present study explored this premise. Patients ( n  = 1,542) presenting to a tertiary-care, outpatient pain clinic completed a cross-sectional survey consisting of regularly collected clinical data and validated measures. Path analysis suggested that the impact of childhood abuse on sensory and affective pain-related characteristics was partially explained by perceived emotional support. Survivors of childhood abuse display a more complex clinical pain phenotype and this extends to more negative perceptions of social support. Our findings may reflect processes whereby childhood abuse negatively impacts social relationships across the lifespan, and these negative social perceptions and relationships influence sensory and affective components of pain., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2022 Pierce, Presto, Hinckley, Hassett, Dickens, Schneiderhan, Grace and McAfee.)