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The development of the boundary layer leading to separation of the flow from the surface along with the formation of the wake regions dramatically increases the overall convective heat transfer coefficient and the exerted drag force on the body. Sustainable building designs are usually encountered with energy issues mainly related to heat loss through the facades due to convective heat transfer and aerodynamic loading problems on the structure due to severe drag forces on facades. Flow control has been demonstrated as a promising tool for reducing wake intensity and preventing flow separation in different areas of aerospace and mechanical engineering. This paper numerically investigates the feasibility and efficiency of utilizing a novel idea based on locating flow controlling blades (FCBs), designed by the Department of Building Aerodynamics of the Solar Decathlon China 2013 (SDC 2013) Team of Iran, in the periphery of the external facades of the house in order to control the external flow and make it more streamlined than the real case of wind around approximately cubic shaped houses, while the objective is to reduce the convection heat loss from the walls and drag force exerted on them. As a case study, the smart sustainable house (Shāremān) was designed by the RTEOPT (Research Team for Energy Optimization and Passive-house Technologies) and participated in the SDC 2013 held by the U.S. DOE and National Energy Administration of China is presented. A 2D incompressible steady computational fluid dynamics solver, based on the finite volume method in the available commercial software package Fluent, is employed, and wind directions varying from 0 to 330 are resolved. The numerical results show an average reduction of about 15.6% for convective heat transfer coefficient over 12 different conditions; also, a decrease of about 4.8% is observed for the pressure difference between the stagnation point and the opposing corresponding point behind the body of the house. [ABSTRACT FROM AUTHOR]

In this study a multi-objective genetic algorithm is utilized to obtain a Pareto optimal set of solutions for geometrical characteristics of airfoil sections for 10-meter blades of a horizontal axis wind turbine. The performance of the airfoil sections during the process of energy conversion is evaluated deploying a 2D incompressible unsteady CFD solver and the second law analysis. Artificial neural networks are trained employing CFD obtained data sets to represent objective functions in an algorithm which implements exergetic performance and integrity characteristics as optimization objectives. The results show that utilizing the second law approach along with Pareto optimality concept leads to a set of precise solutions which represent minimum energy waste, maximum efficiency, and topmost stability. Furthermore, enhanced rotor performance coefficients are observed through a BEM study which compares conventional designs with the second law obtained configurations. Exergy analysis is believed to be an efficient tool in the optimal design of wind turbine blades with the capability of determining the amount of lost opportunities to do useful work. [ABSTRACT FROM AUTHOR]

Background: Inflammatory mediators are an important component in the pathophysiology of the coronavirus disease 2019 (COVID-19). This study aimed to assess the effects of reducing inflammatory mediators using hemoperfusion (HP) and continuous renal replacement therapy (CRRT) on the mortality of patients with COVID-19. Materials and Methods: Twelve patients with confirmed diagnosis of COVID-19 were included. All patients had acute respiratory distress syndrome (ARDS). Patients were divided into three groups, namely, HP, CRRT and HP+CRRT. The primary outcome was mortality and the secondary outcomes were oxygenation and reduction in inflammatory mediators at the end of the study. Results: Patients were not different at baseline in demographics, inflammatory cytokine levels, and the level of acute phase reactants. Half of the patients (3 out of 6) in the HP+CRRT group survived along with the survival of one patient (1 out of 2) in the HP group. All four patients in the CRRT group died. Serum creatinine (SCr), Interleukin-1 (IL1), Interleukin-6 (IL6), Interleukin-8 (IL8), partial pressure of oxygen (PaO2), O2 saturation (O2 sat), and hemodynamic parameters improved over time in HP+CRRT and CRRT groups, but no significant difference was observed in the HP group (All Ps > 0.05). Conclusion: Combined HP and CRRT demonstrated the best result in terms of mortality, reduction of inflammatory mediators and oxygenation. Further investigations are needed to explore the role of HP+CRRT in COVID-19 patients. [ABSTRACT FROM AUTHOR]

So far, too little attention has been paid to total burden of healthcare associated infections (HAIs) in Iran. In the present study, we aimed to assess the rate of HAIs, as well as economic burden of hospitalization and antibiotic related cost associated with HAIs in ICU at training Taleghani hospital in Iran and to compare our results with national nosocomial infections surveillance (NNIS) system. This research to date for the first time has tended to focus on the economic burden of HAIs rather than epidemiology of HAIs evaluation. The total of 474 patients was followed up in this study. Overall, the rate of HAIs was 19.2% in which ventilator associated pneumonia (VAP) was dominant HAIs and followed by urinary tract infection (UTI). Importantly, mortality rate increased significantly in infected patients. The highest total hospitalization economic burden and antibiotic related cost were observed for patients having blood stream infection (BSI). The results demonstrated significant differences between antibiotic related cost in patients and uninfected patients. Antibiotic related absolute extra cost for HAIs was 2.09 PPP$ per day. Estimation of direct annually HAIs associated economic burden of antibiotic and Total hospitalization was 433,382.4 PPP$ and 705,024 PPP$ respectively in Iran at intensive care unit (ICU). The most obvious findings were a strong relationship between relatively heavy antibiotic related financial burden, higher mortality rate, longer hospitalization time, and HAIs emergence on the Iranian national health system. It also reflects, more fundamentally a shift toward the need for comprehensive thinking about HAIs at ICU ward from Iran's hospitals. On the question of the research found that: With the implementation of policies and strategies to reduce hospital infections, which will benefit; Patient, Society, and/or national health system?!. [ABSTRACT FROM AUTHOR]