Per- and polyfluoroalkyl substances (PFASs) are a group of emerging contaminants, that have a wide range of applications in industrial and commercial products. The direct discharge of untreated industrial and domestic wastewater into freshwater bodies is a common practice in developing countries, which are the main contributors to PFASs in the aquatic environment. The situation is further worsened due to poor wastewater treatment facilities and weak enforcement of environmental regulations in countries like Pakistan.
View Article and Find Full Text PDFPer- and polyfluoroalkyl substances (PFASs) are a large group of chemicals reported in global environment and are responsible for various adverse impacts on humans and environment. We report a comprehensive study on occurrence of PFASs, including legacy, substitute and emerging ones, from Pakistan. Surface water samples were collected from five ecologically important freshwater reservoirs in Pakistan, namely, Head Panjnad (HP), Head Trimmu (HT), Chashma Barrage (CB), Head Blloki (HB), and Head Qadirabad (HQ).
View Article and Find Full Text PDFIn this study, a multi-objective topology optimization method has been formulated and carried out for various resection types, with minimization of a weighted sum of the compliance (maximized stiffness) under six routine activities of daily life as the objective function and volume reduction as a constraint. Unique prosthetic geometries with low weight and remarkable strength closely matching the pelvic bone shape were obtained. The strength of the optimized implants was investigated through finite element analysis and it has been found that the initial geometries of the optimized implants could withstand the static loading conditions of various routine activities having less stress concentration areas.
View Article and Find Full Text PDFThe aim of this study was to design a hemi-pelvic prosthesis for a patient affected by pelvic sarcoma. To investigate the biomechanical functionality of the pelvis reconstructed with designed custom-made prosthesis, a patient-specific finite element model of whole pelvis with primary ligaments inclusive was constructed based on the computed tomography images of the patient. Then, a finite element analysis was performed to calculate and compare the stress distribution between the normal and implanted pelvis models when undergoing three different static conditions-both-leg standing, single-leg standing for the healthy and the affected one.
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