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The existence of large-scale turbulent structures within a porous medium, generated through the interaction with a turbulent outer flow, is a highly debated topic, albeit most of the analysis is based on computational studies. This study contributes to the ongoing discussion by providing detailed point-measurements of the velocity in both regions by means of Particle Image Velocimetry (PIV). Two porous models of different porosity are investigated at three Reynolds numbers. The design of the experiments is based on theoretical studies to guarantee the presence of an unperturbed viscous layer at the interface (alias permeability Reynolds numbers of order one). Under these conditions and in compliance with theoretical predictions, the PIV data show the rapid dumping of turbulent fluctuations within the first pore cavities and can be used to validate closure models for volume-averaged computational studies. A point-data analysis is applied in the interfacial region by requiring continuity of tangential velocity and shear stress. The presence of the attached viscous layer implies that the coupling condition for momentum transfer must be controlled by shear, leading to the well-known Beavers and Joseph coupling condition. PIV data corroborate this statement and show the close interdependency between the penetration depth of the outer flow in the porous media and the characteristics of the vortical secondary flows induced by the strain rate at the pore scale. Consequently, the Beavers and Joseph-slip coefficient depends only upon the topology of the porous medium, at least as long as no transition to a perturbed mixing layer occurs at the interface. [ABSTRACT FROM AUTHOR]

Objectives: to compare the sociodemographic and clinical severity indicators of hospitalized people with HIV in relation to clinical outcomes and urgent hospital admission., Methods: a retrospective cohort study was conducted with 102 medical records of HIV-infected individuals hospitalized in a hospital in southern Brazil. In addition to descriptive analysis, Fisher's exact test, Pearson's Chi-square, and logistic regression were used., Results: the data showed a significant direct effect on severity indicators in the following variables: male sex (p=0.013), skin color (p=0.023), level of education (p=0.000), urgent admissions (p=0.000), late diagnosis (p=0.001), diabetes mellitus (p=0.001), hypertension (p=0.004), kidney disease (p=0.002), high viral load (p=0.006), CD4+ count below 200 (p=0.005), fever (p=0.016), weight loss (p=0.013), co-infection with hepatitis C (p=0.004), and mortality (p=0.007)., Conclusions: three sociodemographic and thirteen clinical markers were identified as being associated with the risk of clinical deterioration in hospitalized people with HIV.

Objective: to analyze the frequency and associated risk factors for COVID-19 infection and the availability of Personal Protective Equipment used by primary healthcare workers., Method: a cross-sectional study was conducted over six months in Rio Grande do Sul. Descriptive analysis was performed, with the comparison of independent samples using Pearson's Chi-square test and Fisher's Exact test (p<.05)., Results: the study included 206 (27%) healthcare workers who presented COVID-19 symptoms. There was a statistical association for the following variables: availability of surgical masks (p=.003), seeking information on the correct use of personal protective equipment (p=.045), having attended people with flu-like syndrome (p=.024), and believing that the highest risk of contamination is when attending a patient positive for coronavirus disease (p=.001)., Conclusion: the availability of personal protective equipment is indispensable for COVID-19 prevention, with special emphasis on the use of surgical masks. Furthermore, the study highlighted the importance of providing Personal Protective Equipment in conjunction with guidance on its use., Highlights: (1) Highlighted impacts on the distribution of PPE necessary for worker safety.(2) Emphasized the need for training and education regarding the use of PPE.(3) Found significance regarding the availability of surgical masks.(4) Identified the need for further research on health safety topics.(5) Revealed a high incidence of symptomatic workers and positive cases of COVID-19.

To evaluate the association of standardized phase angle (SPA) with nutritional status, functional parameters, and postoperative outcomes in surgical cancer patients. This prospective study includes 59 cancer patients from Pelotas (Brazil) admitted for elective cancer surgery. We obtained the phase angle through Bioelectrical Impedance Analysis (BIA) and standardized it according to the population's reference values. We estimated the muscle mass using BIA for later calculation of the Skeletal Muscle Index (SMI) and performed handgrip strength (HGS) and gait speed (GS) tests. We used the Patient-Generated Subjective Global Assessment (PG-SGA) to assess the nutritional status. Postoperative complications and duration of hospital stay were evaluated as the outcomes. The prevalence of malnutrition in the sample was 28.8%, according to ASG-PPP. SPA was statistically lower in patients with malnutrition, with lower HGS and reduced GS. For postoperative outcomes, patients with severe complications and those with prolonged hospitalization also had lower SPA values. The greater the number of functional alterations in patients, the lower the SPA value, mainly when associated with reduced muscle mass assessed by BIA, suggesting that muscle mass reduction plays an important role in the association between functional alterations and phase angle in patients with cancer. According to the parameters used in this study, low SPA value was associated with impaired nutritional and functional status and negative outcomes in the analyzed sample., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: Nutritional deficiency, especially malnutrition, is frequent in cancer patients and is associated with changes in body composition, such as low muscle mass. Phase angle (PhA) has been used as a prognostic indicator and may be related to nutritional status, functionality, and quality of life in these patients. The objectives of this study were to assess the effect of chemotherapy treatment on PhA values, comparing the PhA variation before and after treatment, and to evaluate the PhA correlation, as a muscle mass surrogate, with the physical domain of quality of life, functionality, and nutritional risk in a sample of patients with cancer., Methods: A longitudinal study was conducted in patients with cancer undergoing chemotherapy for the first time. All patients aged 18 years or older, newly diagnosed, and undergoing chemotherapy for the first time were included. To analyze the difference in the PhA means according to the different classification variables, the t-test - or ANOVA - was used. The variation of the final and initial PhA was evaluated through the linear regression test., Results: A total of 175 patients were analyzed, of which 66.3% were female. The mean PhA of the initial assessment was significantly higher when compared to the final assessment of the patients PhA (p = 0.018). In both the initial and final assessments, PhA was correlated with the physical domain (r = 0.29; p < 0.001 and r = 0.19; p = 0.021) and with the functionality score (r = - 0.32; p < 0.001 and r = - 0.30; p < 0.001) and total PG-SGA (r = - 0.31; p < 0.001 and r = - 0.23; p = 0.006)., Conclusion: PhA can be considered a predictor of physical quality of life and functionality in cancer patients receiving chemotherapy treatment., (Copyright © 2023 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.)