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Soft sedimentary rocks, especially mudstones, disintegrated or crumbled when subjected to cyclic drying and wetting, known as slaking, which was the cause of severe slope failures and ground settlement. Drying/wetting and temperature variation are the influential factors of the slaking. In this study, a conventional oedometer was modified to make a drying/wetting cycle with temperature variation to examine the effects of slaking for four materials with different slaking ratios. Further, one of the four materials (Hamamatsu mudstone), showing higher vertical strains along the drying/wetting cycle, was experimented with under three loading conditions (100 kPa, 200kPa & 500 kPa) and drying/wetting cycles, in which the particle breakage was also measured along the drying/wetting cycles. In addition, a needle penetration test was conducted along the drying/wetting cycles. In the continuous drying/wetting cycles, the occurrence of particle breakage was higher in lower-stress conditions, where the void ratio became a governing factor for the breakage over vertical stress. The needle penetration resistance is dependent on two factors which are density and particle size, and there was a trade-off between them along the drying/wetting cycles. After a couple of drying/wetting cycles, the particle crushing resulted in a noticeable reduction in penetration resistance in lower stress conditions.

Objective: To investigate characteristics that may be associated with radiologic and functional findings following discharge in patients with severe coronavirus disease 2019 (COVID-19)., Methods: This single-center, prospective, observational cohort study comprised patients aged >18 years who were hospitalized with COVID-19 pneumonia, between May and October 2020. After 3 to 6 months of discharge, patients were clinically evaluated and underwent spirometry, a 6-minute walk test (6MWT), and chest computed tomography (CT). Statistical analysis was performed using association and correlation tests., Results: A total of 134 patients were included (25/114 [22%] were admitted with severe hypoxemia). On the follow-up chest CT, 29/92 (32%) had no abnormalities, regardless of the severity of the initial involvement, and the mean 6MWT distance was 447 m. Patients with desaturation on admission had an increased risk of remaining CT abnormalities: patients with SpO 2 between 88 and 92% had a 4.0-fold risk, and those with SpO 2 < 88% had a 6.2-fold risk. The group with SpO 2 < 88% also walked shorter distances than patients with SpO 2 between 88 and 92%., Conclusion: Initial hypoxemia was found to be a good predictor of persistent radiological abnormalities in follow-up and was associated with low performance in 6MWT.

Coronavirus disease 2019 (COVID-19) is caused by the SARS-CoV-2 virus, responsible for an atypical pneumonia that can progress to acute lung injury. MicroRNAs are small non-coding RNAs that control specific genes and pathways. This study evaluated the association between circulating miRNAs and lung injury associated with COVID-19. Methods: We evaluated lung injury by computed tomography at hospital admission and discharge and the serum expression of 754 miRNAs using the TaqMan OpenArray after hospital discharge in 27 patients with COVID-19. In addition, miR-150-3p was validated by qRT-PCR on serum samples collected at admission and after hospital discharge. Results: OpenArray analysis revealed that seven miRNAs were differentially expressed between groups of patients without radiological lung improvement compared to those with lung improvement at hospital discharge, with three miRNAs being upregulated (miR-548c-3p, miR-212-3p, and miR-548a-3p) and four downregulated (miR-191-5p, miR-151a-3p, miR-92a-3p, and miR-150-3p). Bioinformatics analysis revealed that five of these miRNAs had binding sites in the SARS-CoV-2 genome. Validation of miR-150-3p by qRT-PCR confirmed the OpenArray results. Conclusions: The present study shows the potential association between the serum expression of seven miRNAs and lung injury in patients with COVID-19. Furthermore, increased expression of miR-150 was associated with pulmonary improvement at hospital discharge.

Hypertensive patients are predisposed to left ventricular (LV) remodeling and frequently exhibit decline in lung function as compared with the general population. Here, we investigated the association between spirometric and echocardiographic data in non-smoking hypertensive subjects and the role of gender in this regard. In a cross-sectional study, 107 hypertensive patients (60 women) enrolled from a university outpatient clinic were evaluated by clinical, hemodynamic, laboratory and echocardiographic analysis. Vital capacity, forced vital capacity (FVC), forced expired volume in 1 s (FEV1) and in 6 s (FEV6), FEV1/FVC ratio and FEV1/FEV6 ratio were estimated by spirometry. In women, higher LV mass index and E/Em ratio correlated with markers of restrictive lung alterations, such as reduced FVC (r=-044; P<0.001; r=-0.42; P<0.001, respectively) and FEV6 (r=-0.43; P<0.001; r=-0.39; P<0.01, respectively), while higher left atrial volume index correlated with markers of obstructive lung alterations, such as reduced FEV1/FVC (r=-055; P<0.001) and FEV1/FEV6 (r=-0.45; P<0.001) ratios. These relationships were further confirmed by stepwise regression analysis adjusted for potential confounders. In men, LV mass index correlated with FVC and FEV6, but these associations did not remain statistically significant after adjustment for confounding variables. Furthermore, inflammatory markers such as plasma C-reactive protein and matrix-metalloproteinases-2 and -9 levels did not influence the association between spirometric and cardiac parameters. In conclusion, these results indicate that LV remodeling is related to restrictive lung alterations while left atrial remodeling is associated with obstructive lung alterations in hypertensive women.

Hypertensive patients exhibit higher cardiovascular risk and reduced lung function compared with the general population. Whether this association stems from the coexistence of two highly prevalent diseases or from direct or indirect links of pathophysiological mechanisms is presently unclear. This study investigated the association between lung function and carotid features in non-smoking hypertensive subjects with supposed normal lung function. Hypertensive patients (n = 67) were cross-sectionally evaluated by clinical, hemodynamic, laboratory, and carotid ultrasound analysis. Forced vital capacity, forced expired volume in 1 second and in 6 seconds, and lung age were estimated by spirometry. Subjects with ventilatory abnormalities according to current guidelines were excluded. Regression analysis adjusted for age and prior smoking history showed that lung age and the percentage of predicted spirometric parameters associated with common carotid intima-media thickness, diameter, and stiffness. Further analyses, adjusted for additional potential confounders, revealed that lung age was the spirometric parameter exhibiting the most significant regression coefficients with carotid features. Conversely, plasma C-reactive protein and matrix-metalloproteinases-2/9 levels did not influence this relationship. The present findings point toward lung age as a potential marker of vascular remodeling and indicate that lung and vascular remodeling might share common pathophysiological mechanisms in hypertensive subjects., (Copyright © 2014 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.)