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.

Hexavalent chromium (Cr(VI)) is a critical pollutant with high toxicity, even at trace concentrations. Cr(VI) is possibly carcinogenic and mutagenic and can produce serious health issues. Hence, it is necessary to remove Cr(VI) from the water before releasing it into the environment. Currently, numerous removal techniques were used. Adsorption is the best method compared to others because it is simple, cheap, highly efficient, and can be used in water having trace concentrations of contaminants. Biomass-based waste materials (BMWs) are found as far better adsorbents than commercially and other available adsorbents. In this study, the existing Cr(VI) removal techniques are reviewed and, a broad range of current research studies of Cr(VI) removal from water by using BMWs are evaluated. This review can be helpful to develop a more efficient, cheap, reliable, and environmentally benign bio-adsorbent. It is obvious after the literature review given herein that BMWs exhibited potential adsorbents for the removal of Cr(VI). Also, the chemically modified adsorbents exhibited a higher adsorption capacity than unmodified adsorbents.

The potential of a biosorbent derived from Arundo donax stem, a readily available agricultural product, was examined to remove Cr(VI) from water. Various techniques such as XRD, FTIR, SEM, and EDX were used for the characterization of the prepared adsorbent. The optimal pH for Cr(VI) biosorption was found to be 2.0. The experimental data best suits the Langmuir isotherm model and pseudosecond-order kinetics. The maximum biosorption capacity (qmax) of the investigated biosorbent for Cr(VI) was evaluated to be 76.92 mg/g by the Langmuir model. From the results of the Cr(VI) biosorption using charred Arundo donax stem powder (CADSP), it can be a novel, cost-efficient, and effective material for removing Cr(VI) from water and wastewater.

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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.