8 research outputs found
Transient MHD Double-Diffusive Natural Convection over a Vertical Surface Embedded in a Non-Darcy Porous Medium
The problem of transient, laminar, MHD double-diffusive free convection over a permeable vertical plate embedded in Darcy and non-Darcy porous medium is numerically investigated. Nonsimilarity solutions are obtained for constant wall temperature and concentration with a specified power law of mass flux parameter. The effects of the magnetic parameter, the inertial coefficient, Lewis number, the buoyancy ratio, and the lateral mass flux on heat and mass transfer coefficients are presented and discussed
International Consensus Statement on Rhinology and Allergy: Rhinosinusitis
Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR‐RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR‐RS‐2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence‐based findings of the document. Methods: ICAR‐RS presents over 180 topics in the forms of evidence‐based reviews with recommendations (EBRRs), evidence‐based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICAR‐RS‐2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence‐based management algorithm is provided. Conclusion: This ICAR‐RS‐2021 executive summary provides a compilation of the evidence‐based recommendations for medical and surgical treatment of the most common forms of RS
Numerical Investigation of Transient Natural Convection of Viscoelastic Fluid Due to a Nonlinearly Stretching Surfaces with a Power-Law Surface Temperature
COMBINED EFFECTS OF JOULE HEATING AND VISCOUS DISSIPATION ON TRANSIENT MHD NATURAL CONVECTION OF VISCOELASTIC FLUID OVER A VERTICAL SURFACE
The combined effects of Joule heating and viscous dissipation on transient Magnetohydrodynamics (MHD) free convective flow of an incompressible electrically- conducting viscoelastic second-order fluid over a vertical surface are investigated numerically. The governing non-linear dimensionless equations are solved using an implicit finite difference scheme of Crank-Nicolson type with a tri-diagonal matrix manipulation. Effects of viscoelastic parameter, Magnetic parameter, Eckert number and Prandtl number on the flow and heat transfer transient characteristics are studied. It was found that, the velocity inside the boundary layer increases as the viscoelastic parameter increases, and accordingly the skin friction coefficient increases. Conversely an opposite behavior is observed for the temperature profiles
Effect of Magnetic Field on Entropy Generation Due to Laminar Forced Convection Past a Horizontal Flat Plate
Magnetic field effect on local entropy generation due to steady two-dimensional laminar forced convection flow past a horizontal plate was numerically investigated. This study was focused on the entropy generation characteristics and its dependency on various dimensionless parameters. The effect of various dimensionless parameters, such as Hartmann number (Ha), Eckert number (Ec), Prandtl number (Pr), Joule heating parameter (R) and the free stream temperature parameter (θ∞) on the entropy generation characteristics is analyzed. The dimensionless governing equations in Cartesian coordinate were solved by an implicit finite difference technique. The solutions were carried out for Ha2=0.5-3, Ec=0.01-0.05, Pr=1-5 and θ∞=1.1-2.5. It was found that, the entropy generation increased with increasing Ha, Ec and R. While, increasing the free stream temperature parameter, and Prandtl number tend to decrease the local entropy generation
COMBINED EFFECTS OF JOULE HEATING AND VISCOUS DISSIPATION ON TRANSIENT MHD NATURAL CONVECTION OF VISCOELASTIC FLUID OVER A VERTICAL SURFACE
Diagnostic accuracy of ePOS score in predicting DNR labeling after ICU admission: A prospective observational study (ePOS-DNR)
Background: Resuscitation can sometimes be futile and making a do-not-resuscitate (DNR) decision is in the best interest of the patient. The electronic poor outcome screening (ePOS) score was developed to predict 6-month poor outcomes of critically ill patients. We explored the diagnostic accuracy of the ePOS score in predicting DNR decisions in the intensive care unit (ICU). Methods: This study was conducted at the ICU of a tertiary referral hospital in Saudi Arabia between March and May 2023. Prospectively, we calculated ePOS scores for all eligible consecutive admissions after 48 h in the ICU and recorded the DNR orders. The ability of the score to predict DNR was explored using logistic regression. Youden's ideal cut-off value was calculated using the DeLong method, and different diagnostic accuracy measures were generated with corresponding 95 % confidence intervals (CIs). Results: We enrolled 857 patients, 125 received a DNR order and 732 did not. The average ePOS score of DNR and non-DNR patients was 28.2±10.7 and 15.2±9.7, respectively. ePOS score, as a predictor of DNR order, had an area under receiver operator characteristic (AUROC) curve of 81.8 % (95% CI: 79.0 to 84.3, P 17 was associated with a sensitivity of 87.2 (95% CI: 80.0 to 92.5, P 17 may help guide clinical decisions to withhold or commence resuscitative measures
