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AbstractA numerical study was conducted to explore the effective usability of prismatic triangular channel solar air heaters integrated with longitudinal fins and quadrilateral rib turbulators. Using the matrix inversion technique and MATLAB-developed code, the governing equations of the system were solved. The analytical model is confirmed, showing commendable agreement with an average discrepancy of 4.2%. For the constant value of quadrilateral rib conditions, the first law and the thermohydraulic performance of the novel air heating system are analyzed by considering the design and operating conditions of Reynolds number, fin height ratio, fin thickness ratio, and number of fins. The achieved results reveal that the provision of fins with rectangular rib roughness enhances the thermal and effective thermal performance by optimizing fin design parameters, leading to a maximum value of 85.48% and 78.58%, respectively. The comparison results reveal that the present work improves the effective thermal performance by 5.14% to 20.2% up to the Reynolds number of 21600. It is an attractive design, achieving a rise in temperature parameter up to 0.012 W/m2K. [ABSTRACT FROM AUTHOR]

Aim: Transcatheter mitral valve-in-valve (TMViV) replacement for degenerated surgically implanted bioprosthetic valves has been described by both transseptal and transapical approaches. The balloon-expandable Myval transcatheter valve (Meril Life Sciences, Vapi, India) is commonly used for transcatheter valve-in-valve procedures in India. This study aimed to report in-hospital, 30-day, and 1-year outcomes of Myval patients who underwent TMViV in a single tertiary care centre in India., Methods: Symptomatic patients with surgical bioprosthetic mitral valve failure with New York Heart Association (NYHA) class III-IV symptoms, despite optimal medical therapy and high or very high risk for redo surgery, were assigned to TMViV following heart team discussions. Data were retrospectively collected and outcomes assessed., Results: Twenty patients were treated, with mean age 64.4 years, 60% were female, and mean Society of Thoracic Surgeons (STS) predicted risk of operative mortality score was 8.1. The failure mechanism was combined stenosis and regurgitation in 60% of patients. Technical success was achieved in 100% of patients. The mean postprocedure and 30-day gradients were 4.6±2.7 and 6.3±2.1, respectively. None of them had significant valvular or paravalvular leaks or left ventricular outflow tract obstruction. All-cause mortality at 1 year was 10%, and all survivors were in New York Heart Association (NYHA) class I or II., Conclusion: TMViV replacement with a Meril Myval can be safely performed with high technical success, and low 30-day and 1-year mortality., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)