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Zinc-air batteries (ZABs) have garnered significant interest as a viable substitute for lithium-ion batteries (LIBs), primarily due to their impressive energy density and low cost. However, the efficacy of zinc-air batteries is heavily dependent on electrocatalysts, which play a vital role in enhancing reaction efficiency and stability. This scholarly review article highlights the crucial significance of electrocatalysts in zinc-air batteries and explores the rationale behind employing Fe-Co-Ni-Zn-based metal-organic framework (MOF)-derived hybrid materials as potential electrocatalysts. These MOF-derived electrocatalysts offer advantages such as abundancy, high catalytic activity, tunability, and structural stability. Various synthesis methods and characterization techniques are employed to optimize the properties of MOF-derived electrocatalysts. Such electrocatalysts exhibit excellent catalytic activity, stability, and selectivity, making them suitable for applications in ZABs. Furthermore, they demonstrate notable capabilities in the realm of ZABs, encompassing elevated energy density, efficacy, and prolonged longevity. It is imperative to continue extensively researching and developing this area to propel the advancement of ZAB technology forward and pave the way for its practical implementation across diverse fields.
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We studied the sequestration of hexavalent chromium Cr(VI) from an aqueous solution using chemically modified pomegranate peel (CPP) as an efficient bio-adsorbent. The synthesized material was characterized by X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS), and scanning electron microscopy (SEM). The impacts of parameters like solution pH, Cr(VI) concentration, contact time, and adsorbent dosage were investigated. Experimental results of the isotherm studies and adsorption kinetics were found agreeing to the Langmuir isotherm model and pseudo-second-order kinetics, respectively. The CPP showed appreciable Cr(VI) remediation capacity with a maximal loading capacity of 82.99 mg/g at pH 2.0, which was obtained in 180 min at room temperature. Thermodynamic studies revealed the biosorption process as spontaneous, feasible, and thermodynamically favorable. The spent adsorbent was eventually regenerated and reused, and the safe disposal of Cr(VI) was ensured. The study revealed that the CPP can be effectively employed as an affordable sorbent for the excision of Cr(VI) from water.
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INTRODUCTION: This study was conducted with the objective to analyze the out-of-pocket (OOP) healthcare expenditure and catastrophic healthcare expenditure (CHE) on chronic non-communicable diseases (CNCD) among the elderly population, and the association of CHE on CNCD with associated factors among the same population. MATERIALS AND METHODS: We collected data from the elderly population of Dharan Sub-metropolitan city of the Eastern Nepal via door-to-door survey and face-to-face interview. The ten wards out of twenty were chosen by lottery method, and the equal proportion out of 280 samples was purposively chosen from each of ten wards (28 participants from each selected ward). The data were entered in Microsoft Excel 2019 v16.0 and statistical analysis was performed by using statistical package for social sciences, IBM SPSS® v21. The chi-square test was used to test the group differences. Multivariable logistic regression was used to determine independent factors associated with CHE (all variables with P < 0.20), and adjusted odds ratios (AOR) were calculated at 95% confidence interval (CI). RESULTS: The median household, food and health expenditures were 95325 (72112.50-126262.50), 45000 (33000-60000) and 2100 (885.00-6107.50) NPR respectively. The proportion of the participants with CHE was 14.6%. The single living participants had 3.4 times higher odds of catastrophic health expenditure (AOR = 3.4, 95% CI = 1.2-9.6, P-value = 0.022) than those who are married. Similarly, those who had cancer had 0.1 times lower odds of CHE (AOR = 0.1, 95% CI = 0.0-0.2, P-value = <0.001) than those without cancer. CONCLUSION: The elder population had significant financial health shocks due to chronic health ailments. There should be the provision of mandatory health insurance programmes for elderly to cut down the catastrophic healthcare expenditure. Similarly, there should be the provision of exemption scheme for vulnerable elderly who are more likely to face catastrophic expenditure from all available health facilities.
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Gastos en Salud , Enfermedades no Transmisibles , Anciano , Humanos , Enfermedad Catastrófica , Estudios Transversales , Nepal , Enfermedades no Transmisibles/epidemiologíaRESUMEN
During Atrial Fibrillation (AF) more than 90% of the left atrial thrombi responsible for thromboembolic events originate in the left atrial appendage (LAA), a complex small sac protruding from the left atrium (LA). Current available treatments to prevent thromboembolic events are oral anticoagulation, surgical LAA exclusion, or percutaneous LAA occlusion. However, the mechanism behind thrombus formation in the LAA is poorly understood. The aim of this work is to analyse the hemodynamic behaviour in four typical LAA morphologies - "Chicken wing", "Cactus", "Windsock" and "Cauliflower" - to identify potential relationships between the different shapes and the risk of thrombotic events. Computerised tomography (CT) images from four patients with no LA pathology were segmented to derive the 3D anatomical shape of LAA and LA. Computational Fluid Dynamic (CFD) analyses based on the patient-specific anatomies were carried out imposing both healthy and AF flow conditions. Velocity and shear strain rate (SSR) were analysed for all cases. Residence time in the different LAA regions was estimated with a virtual contrast agent washing out. CFD results indicate that both velocity and SSR decrease along the LAA, from the ostium to the tip, at each instant in the cardiac cycle, thus making the LAA tip more prone to fluid stagnation, and therefore to thrombus formation. Velocity and SSR also decrease from normal to AF conditions. After four cardiac cycles, the lowest washout of contrast agent was observed for the Cauliflower morphology (3.27% of residual contrast in AF), and the highest for the Windsock (0.56% of residual contrast in AF). This suggests that the former is expected to be associated with a higher risk of thrombosis, in agreement with clinical reports in the literature. The presented computational models highlight the major role played by the LAA morphology on the hemodynamics, both in normal and AF conditions, revealing the potential support that numerical analyses can provide in the stratification of patients under risk of thrombus formation, towards personalised patient care.