MHD squeezing flow of nanoliquid on a porous stretched surface: numerical study

This work is aimed at conducting a comparative study between two base fluids water as well as ethylene glycol along with nanoparticle (oxide aluminium). Analysis is done for determining unsteadiness between two parallel walls, wherein squeezing of upper wall towards lower is done, while porous stretching surface is lower. The mathematical formulation uses constitutive expression pertaining to viscous nanoliquids. By keeping a variable magnetic field, conduction of nanoliquid is done electrically. The partial differential equations concerning the issue were resolved after transforming to ordinary differential equations by employing forth-fifth Runge-Kutta Fehlberg method. The effect of disparity in various parameters pertaining to temperature, velocity and concentration profile of nanoparticle is first plotted and then tabulated. Based on the obtained results, the velocity field was seen to enhance with rise in squeezing parameter values. Squeezing parameters that possess larger values result in decrease in temperature and concentration profiles of nanoparticles. The heat transfer of nanoliquids was seen to improve with squeezing flow, magnetic field parameter and nanoparticle volume fraction. For the rate of skin friction pertaining to ethylene glycol and water, dominance was seen for magnetic parameter M, suction parameter S and nanoparticle volume fraction parameter

Experimental investigation on the thermal-hydraulic performance of channel with gradient metal foam baffles

Metal foam is a novel material recently utilized in baffles as an alternative to solid baffles for reducing flow resistance. However, the metal foam baffles are accompanied by low heat transfer efficiency. To overcome this issue, a new design of copper foam baffles has been suggested in this research, called baffles having a gradient pore density of the copper foam. The pore density either increases or decreases towards the wall. So, the experimental tests were carried out in a square channel and heated uniformly at the bottom wall of the test section. Its walls are mounted copper foam baffles at a fixed porosity of 95%. Baffles were alternately fixed upon the walls' bottom and top in staggered mode. The results were determined for various kinds of copper foam (10 and 20) pores per inch (PPI), and the gradient pore density was either with the order decreasing (DPPI) 10/20 PPI or increasing (IPPI) 20/10 PPI with a window cut ratio of 25% and a constant heat flux of 4.4 kW/m2 . The Reynolds number was changed from 3.8x104 to 5.4x104 . The data for conventional copper solid baffles were used to compare the influence of foam metal type. The obtained results revealed an enhancement in thermohydraulic performance for baffles with a gradient pore density of the order decreasing DPPI (10/20 PPI) higher than all the models of copper foam baffles

The performance of Al2O3 crude oil on nonlinear stretching sheet

Nanotechnology has enticed a good attention in boosting base fluid such as crude oil. A mathematical model is investigated to study MHD Carreau crude oil based Al2O3 nanofluids. Analysis over stretching sheet surface is illustrated that include consideration of nanoparticles shape with high (E1=5.0) and low (E1=0.0) electric field. Depending on nanoparticle shape, deferent expects of nanofluids flow such that the shapes as (sphere, cylinder, lamina) to boost the heat and mass transfer. Employing convenient self-similar transformation, the set of partial differential equation converted to dimensionless system. These equations has numerically solution by apply Runge-Kutta Fehlberg form plus so-called shooting technique and solving algebraically in Maple 18. Effect of relevant parameters on all concerned profile are incurred to examine the heat and mass transfer properties. For thermal radiation and heat generation parameters the profiles are on negative worth of temperature, is seen in the out of boundary region all these physical behaviours are due to the combined effects of the viscosity and density of the crude oil. The result obtained that heat generation, Brownian motion and magnetic field hit a dominant role on Al2O3 - crode oil . The investigation revealed that there is no important role for nanoparticle shapes on Al2O3 crude oil

Radiative MHD sutterby nanofluid flow past a moving sheet: Scaling group analysis

The present theoretical work endeavors to solve the Sutterby nanofluid flow and heat transfer problem over a permeable moving sheet, together with the presence of thermal radiation and magnetohydrodynamics (MHD). The fluid flow and heat transfer features near the stagnation region are considered. A new form of similarity transformations is introduced through scaling group analysis to simplify the governing boundary layer equations, which then eases the computational process in the MATLAB bvp4c function. The variation in the values of the governing parameters yields two different numerical solutions. One of the solutions is stable and physically reliable, while the other solution is unstable and is associated with flow separation. An increased effect of the thermal radiation improves the rate of convective heat transfer past the permeable shrinking sheet

Left Ventricular Mechanics in Patients with Abnormal Origin of the Left Main Coronary Artery from the Pulmonary Trunk Late after Successful Repair

Our aim was to evaluate left ventricular (LV) mechanics by using speckle tracking echocardiography (STE) in asymptomatic patients with abnormal origin of the left main coronary artery from the pulmonary trunk (ALCAPA), late after successful repair, in the presence of LV ejection fraction (EF) >50%.Objective: Our aim was to evaluate left ventricular (LV) mechanics by using speckle tracking echocardiography (STE) in asymptomatic patients with abnormal origin of the left main coronary artery from the pulmonary trunk (ALCAPA), late after successful repair, in the presence of LV ejection fraction (EF) >50%. Methods: We studied 30 ALCAPA patients (median age 4 years, range 1-25 years, NYHA class I, LVEF >50%) and 16 healthy age- and sex-matched controls (median age 5 years, range 1-25 years). All underwent standard echocardiographic evaluation and STE. Results: LV dimensions and LVEF (63.6 +/- 8.2% vs. 64.1 +/- 5.1%, p = 0.826) were not different between patients and controls. Diastolic parameters were significantly abnormal in our patients versus controls (E/e' average: 11.9 5.8 vs. 6.6 +/- 3.0, p = 0.0014). Global LV longitudinal strain was significantly lower in ALCAPA patients versus controls (-17.6 +/- 3.5% vs. 23.4 +/- 3.1%, p < 0.0001). LV torsion (9.1 +/- 4.9 vs. 11.9 +/- 3.3, p = 0.046) was significantly impaired in ALCAPA patients. Conclusions: After successful repair in asymptomatic ALCAPA patients, despite an LVEF >50%, diastolic function, LV longitudinal deformation and LV torsion remain impaired. We suggest including a detailed study of the diastolic function and cardiac mechanics in the clinical follow-up of these patients to identify the subgroup of patients at higher risk. (C) 2016 S. Karger AG, Base

Incivility among nursing faculty: A multi-country study

Background: In nursing programs, incivility can be a main issue affecting future registered nurses, and this may threaten patient safety. Nursing faculty play an important role in this scenario to reduce incivility. Purpose: The aim of this study was to assess incivility among nursing faculty in different countries. Method: This descriptive (cross-sectional) study was conducted to assess the extent of incivility among nursing faculty by using Incivility in Nursing Education-Revised tool and a non-probability (convenience) sampling method was used. Three hundred ninety-five nursing faculty in 10 countries distributed in four continents participated in this study. Results: The results indicated that levels of incivility among participants in different countries were significantly different. Also, there was a significant difference (F = 9.313, P value = 0.000) among the nursing faculty concerning the behaviours that have been rated as disruptive. Furthermore, there was a significant difference (F = 6.392, P value = 0.000) among participants regarding uncivil behaviours that have occurred during the past 12 months. Conclusion: Regular assessments are needed to highlight uncivil behaviours and reduce them by making policies and rules in order to enhance academic achievement in nursing education

STIGMA TOWARDS HEALTH CARE PROVIDERS TAKING CARE OF COVID-19 PATIENTS: A MULTI-COUNTRY STUDY

Background: Health care providers (HCPs) have always been a common target of stigmatization during widespread infections and COVID-19 is not an exception. Aim: This study aims to investigate the prevalence of stigmatization during the COVID-19 pandemic among HCPs in seven different countries using the Stigma COVID-19 Healthcare Providers tool (S19-HCPs). Design: Cross-sectional. Methods: The S19-HCPs is a self-administered online survey (16-item) developed and validated by the research team. The participants were invited to complete an online survey. Data collection started from June–July 2020 using a convenience sample of HCPs from Iraq, Jordan, Egypt, Saudi Arabia, Indonesia, Philippines, and Kuwait. Results: A total number of 1726 participants were included in the final analysis. The majority of the study participants were Jordanians (22%), followed by Kuwaitis (19%), Filipinos (18%) and the lowest participants we Indonesians (6%). Other nationalities were Iraqis, Saudis, and Egyptians with 15%, 11% and 9% respectively. Among the respondents, 57% have worked either in a COVID-19 designated facility or in a quarantine center and 78% claimed that they had received training for COVID-19. Statistical significance between COVID-19 stigma and demographic variables were found in all aspect of the S19-HCPs. Conclusion: The findings of this study demonstrated high levels of stigmatization against HCPs in all the included seven countries. On the other hand, they are still perceived positively by their communities and in their utmost, highly motivated to care for COVID-19 patients. Educational and awareness programs could have a crucial role in the solution of stigmatization problems over the worl