COVID‑19 Pandemic: Effect of Specific and Non-Specific Prevention Measures on the Risk of SARS‑CoV‑2 Infection in Employees of Healthcare Organizations

From the very onset of SARS‑CoV‑2 spreading, active involvement in the COVID‑19 epidemic process made the healthcare professionals (HCPs) a vulnerable group with higher risks of contracting the disease, severe course and fatal outcome.The aim. We aimed at studying the impact of specific and non-specific preventive measures on the risk of SARS‑CoV‑2 infection among the HCPs in a large industrial region settings during the COVID‑19 pandemic.Materials and methods. We analyzed the data obtained using 1 905 questionnaires for the personnel of infectious hospitals for treatment of COVID‑19 patients and non-core healthcare facilities in a large industrial region during the COVID‑19 pandemic, 100 questionnaires on adherence of the employees to hand hygiene and antiseptics, the results of the tests for specific IgG to the SARS‑CoV‑2 nucleocapsid (2 200 samples), as well as the results of assessment of viral and bacterial contamination of the outer surface of the personal protective equipment for infectious hospital staff (108 specimens).Results and discussion. In the course of the study, an effect of failure in the implementation of some specific and non-specific preventive measures on an increase in the incidence of COVID‑19 in various healthcare professionals has been identified. The COVID‑19 pandemic once again emphasized the need to save lives and health of the HCPs as socially significant category of citizens under the spread of pathogens with high epidemic potential, applying a complex of specific and non-specific measures that are not mutually exclusive

Double-Chamber Microbial Fuel Cell with a Non-Platinum-Group Metal Fe-N-C Cathode Catalyst

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Non-Pt-group metal (non-PGM) materials based on transition metal-nitrogen-carbon (M-N-C) and derived from iron salt and aminoantipyrine (Fe-AAPyr) of mebendazole (Fe-MBZ) were studied for the first time as cathode catalysts in double-chamber microbial fuel cells (DCMFCs). The pH value of the cathode chamber was varied from 6 to 11 to elucidate the activity of those catalysts in acidic to basic conditions. The Fe-AAPyr- and Fe-MBZ-based cathodes were compared to a Pt-based cathode used as a baseline. Pt cathodes performed better at pH 6-7.5 and had similar performances at pH 9 and a substantially lower performance at pH 11 at which Fe-AAPyr and Fe-MBZ demonstrated their best electrocatalytic activity. The power density achieved with Pt constantly decreased from 94-99 μW cm-2 at pH 6 to 55-57 μW cm-2 at pH 11. In contrast, the power densities of DCMFs using Fe-AAPyr and Fe-MBZ were 61-68 μW cm-2 at pH 6, decreased to 51-58 μW cm-2 at pH 7.5, increased to 65-75 μW cm-2 at pH 9, and the highest power density was achieved at pH 11 (68-80 μW cm-2). Non-PGM cathode catalysts can be manufactured at the fraction of the cost of the Pt-based ones. The higher performance and lower cost indicates that non-PGM catalysts may be a viable materials choice in large-scale microbial fuel cells

Optimized activated carbon cathode in membraneless single chamber microbial fuel cell treating acetate

Activated Carbon (AC) have been used as cheap alternative cathode for microbial fuel cell (MFC) applications. Different parameters (applied pressure and temperature treatment) have been changed and the cathode performances have been studied in half electrochemical cell and in single chamber MFC. The best cathode polarization was achieved at 2 mT applied pressure and temperature treatment of 200°C. The cathodes were also tested in microbial fuel cell (MFC) fed with phosphate buffer and sodium acetate.</p

Enzymatic Oxygen Microsensor Based on Bilirubin Oxidase Applied to Microbial Fuel Cells Analysis

A selective oxygen biosensor based on bilirubin oxidase (BOx) was developed. The sensor was used for determining oxygen profiles in a membraneless, single-chamber microbial fuel cell (SCMFC), fed with raw wastewater. The linear response of the sensor was optimized by a diffusion layer of silica gel. A computer-controlled stage was used to obtain accurate and precise measurements. Oxygen concentration in biofilms covering electrodes was measured, showing 3mgL-1 of O2 in the bulk solution, decreasing to 0mgL-1 in the cathodic biofilm. The MFC generated power in the range of 0-0.08mW, associated to the oxygen content

Enzymatic Oxygen Microsensor Based on Bilirubin Oxidase Applied to Microbial Fuel Cells Analysis

A selective oxygen biosensor based on bilirubin oxidase (BOx) was developed. The sensor was used for determining oxygen profiles in a membraneless, single-chamber microbial fuel cell (SCMFC), fed with raw wastewater. The linear response of the sensor was optimized by a diffusion layer of silica gel. A computer-controlled stage was used to obtain accurate and precise measurements. Oxygen concentration in biofilms covering electrodes was measured, showing 3 mg L−1 of O2 in the bulk solution, decreasing to 0 mg L−1 in the cathodic biofilm. The MFC generated power in the range of 0–0.08 mW, associated to the oxygen content

Parameters characterization and optimization of activated carbon (AC) cathodes for microbial fuel cell application

Activated carbon (AC) is employed as a cost-effective catalyst for cathodic oxygen reduction in microbial fuel cells (MFC). The fabrication protocols of AC-based cathodes are conducted at different applied pressures (175-3500. psi) and treatment temperatures (25-343. °C). The effects of those parameters along with changes in the surface morphology and chemistry on the cathode performances are comprehensively examined. The cathodes are tested in a three-electrode setup and explored in single chamber membraneless MFCs (SCMFCs). The results show that the best performance of the AC-based cathode is achieved when a pressure of 1400. psi is applied followed by heat treatment of 150-200. °C for 1. h. The influence of the applied pressure and the temperature of the heat treatment on the electrodes and SCMFCs is demonstrated as the result of the variation in the transfer resistance, the surface morphology and surface chemistry of the AC-based cathodes tested. © 2014

The effects of carbon electrode surface properties on bacteria attachment and start up time of microbial fuel cells

Surface roughness, porosity and contact angles of different carbon paper materials (TORAY paper with PTFE from 0% to 60% of and SGL paper with 0% and 20% of PTFE) suitable as electrodes in microbial fuel cells were investigated. The changes of contact angle between dry and clean anode surfaces and the ones after exposure to wastewater were measured using different liquids (pure water and sodium acetate solutions). The results showed that bacterial attachment to the carbon papers caused a significant decrease in the contact angle, shifting the surface property from highly hydrophobic to slightly hydrophobic or even hydrophilic. The quantity of biofilm attached on the anode surface decreased with the increase in PTFE content. Positive correlation between dry biomass content and the amount of pores at the small scale (5-10 lm) was observed. The start up time of MFCs was shortened by using the carbon anodes without PTFE or with low PTFE content (< 20 wt%), probably due to the easier biofilm attachment on the surface. On the contrary, the carbon anodes with high PTFE contents had longer start up time. After several cycles of MFC operation, the performances became similar (20-30 mV of differences) regardless of the carbon anode used. © 2013 Elsevier Ltd. All rights reserved