Particle Swarm Optimization Trained Artificial Neural Network to Control Shunt Active Power Filter Based on Multilevel Flying Capacitor Inverter

© 2020 by the authors; licensee IIETA, Edmonton, Canada. This article is an open-access article distributed under the terms and conditions of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0/).Shunt Active Power Filters (SAPF) are an emerging power electronics-based technology to mitigate harmonic and improve power quality in distribution grids. The SAPF proposed in this paper is based on three-phase Flying Capacitor Inverter (FCI) with a three-cell per phase topology, which has the advantage to provide voltage stress distribution on the switches. However, controlling the voltage of floating capacitors is a challenging problem for this type of topology. In this paper, a controller based artificial neural networks optimized with particle swarm optimization (ANN-PSO) is proposed to regulate the filter currents to follow the references extracted by the method of synchronous reference frame (SRF). The simulation results showed an enhancement of the power quality with a significant reduction in the THD levels of the current source under various loading conditions, which confirms the effectiveness, and robustness of the proposed control scheme and SAPF topology.Peer reviewe

HCV Seroconversion in two Egyptian Hemodialysis Units: Role of Detection Method and Patients Isolation

Background: Hepatitis C virus (HCV) infection is a significant cause of morbidity and mortality in end stage renal disease (ESRD) patients on hemodialysis (HD).  Routine HCV viremia screening is recommended in those patients but it is not applied.Aim: To evaluate the seroconversion rate in HD patients based on viremia detection compared to antibody (Ab), and to assess the role of isolation on the rate of seroconversion in those patients.Materials and Methods: One hundred ESRD patients from two HD units using same infection control criteria were enrolled in the study; only one unit was applying isolation for HCV patients. Patients were followed up for 12 month; HCV positivity was tested at the begining of the study and after 12 month of HD. HCV Ab and viremia were detected by third generation ELISA and PCR respectively.Results: The seroconversion rate was 0% based on HCV Ab detection by ELISA, compared with the 16 % seroconversion rate based on viremia detection by PCR. Notably, viremia seroconversion was seen only in the HD unit lacking the isolation system.Conclusion: HCV screening in HD units should be based on viremia detection; isolation in HD units prevents HCV spreading

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries