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Degree of increase in pulmonary artery pressure (PAP) and adaptive responses in right ventricular morphology and mechanics play an important role in the prognosis of chronic obstructive pulmonary disease (COPD) patients. Three dimensional echocardiography and deformation imaging are recent advancements in echocardiography that allow more through assessment of right ventricle. We aimed to investigate right ventricular geometry and mechanics in a stable COPD population living at moderately high altitude. A total of 26 stable COPD patients with variable disease severity were included to this study. Pulmonary function tests, six minutes walking test (6MWT) and two- and three-dimensional echocardiography were performed for evaluation and data collection. Both systolic (43.06 ± 11.79 mmHg) and mean (33.38 ± 9.75 mmHg) PAPs were significantly higher in COPD patients compared to controls (p < 0.05, p < 0.001; respectively). Right ventricular volumes were similar between groups, although right ventricular free wall thickness was significantly increased in COPD group. The number of subjects with a sub-normal (<40 %) right ventricular ejection fraction was significantly higher in COPD group (45.8 vs. 17.4 %, p < 0.05), and the mean right ventricular strain was significantly lower (-21.05 ± 3.80 vs. -24.14 ± 5.37; p < 0.05). Only mean PAP and body surface area were found as independent predictors for 6MWT distance. Increased PAP and reduced right ventricular contractility were found in COPD patients living at moderately high altitude, although right ventricular volumes were normal. Similar findings can be expected in other COPD patients with high PAP, since these findings probably represents the effect of increased PAP on right ventricular mechanics.

Implementation of industrial wastes such as bottom ash in ground improvement can be cost-effective and environment-friendly. Ground improvement is an effective method of mitigation to improve problematic soils including soft kaolin clay soils as the problematic soils always expose to the severe settlements, low shear strength, immoderate plasticity, greater compressibility, dispersivity, bulging, erodibility, and susceptibility to climatic variables. Several studies conducted on the granular column using the bottom ash column. However, only a few studies have reported findings coherent with the statistical analysis. In this study, the lateral load capacity of bottom ash column-kaolin clay has been conducted. Coherently, the reinforced kaolin clay samples were tested via particle size distribution, Atterberg limit test, relative density, compaction test, permeability test, unconfined compression test, and unconsolidated undrained triaxial test with the single and group of encapsulated bottom ash columns with the geotextile encasement and a prediction model was developed. The effect of a number of columns, column diameter, column height, area replacement ratio, height penetration ratio, height-diameter column ratio, volume replacement ratio, and confining pressures on the shear strength of the single and group of encapsulated bottom ash columns have been investigated. The findings showed the effectiveness of using the bottom ash columns at various number of column, column diameter, column height, area replacement ratio, height penetration ratio, height-diameter column ratio, volume replacement ratio, and confining pressures can enhance the shear strength of the soil up to 77.00% at the optimal utilization of single encapsulated bottom ash column of 10-mm diameter and 80-mm height. Therefore, the study proved that the utilization of bottom ash waste as a granular column can significantly enhance the lateral load capacity of soft kaolin clay soil., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)