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The purpose of the study is to indicate a three-dimensional convective heat transfer properties evaluation of magnetohydrodynamics nanofluid flow, comprising motile oxytactic microorganisms and nanoparticles, passing through a rotating cone.

The imposed technique for solving the governing equations is the Runge–Kutta fifth-order method. The main point of this survey is to diagnosis the influence of diverse factors on velocity, temperature distributions and concentration profile. Furthermore, appending the magnetic field, thermal radiation and viscous dissipation in calculations; also, simultaneous involvement of heat absorption and excretion has been represented as novelties.

The results elucidate that by changing the Peclet number from 1 to 2, the dimensionless concentration of the microorganisms has been diminished by about 34.37%. In addition, variation of the magnetic parameter from 0 to 1 has been resulted in reducing the temperature distribution by about 3.11%.

Recently, attention has been absorbed to adding the motile microorganisms to nanofluid for enhancement of heat transfer and avoiding aggregation of particles. In this regard, the hydrothermal flow of microorganisms has been investigated in this study.

The purpose of this paper is to investigate micropolar magnetohydrodynamics (MHD) fluid flow passing over a vertical plate. Three different base fluids have been used that include water, ethylene glycol and ethylene glycol/water (50%–50%). Also, a nanoparticle was used in all of the base fluids. The effects of natural convection heat transfer and magnetic field have been taken into account.

The main purpose of solving the governing equations is to scrutinize the effects of the magnetic parameter, the nanoparticle volume fraction, micropolar parameter and nanoparticles shape factor on velocity, temperature and microrotation profiles, the skin friction coefficient and the Nusselt number. These surveys have been considered for three base fluids simultaneously.

The results indicate that for water-based fluids, the temperature profile of lamina-shaped nanoparticles is 38.09% higher than brick-shaped nanoparticles.

This paper provides micropolar MHD fluid flow analysis considering natural convection heat transfer and magnetic field in three different base fluids. The aim of assessments is the diagnosis of some parameter effects, such as magnetic parameter and nanoparticle volume fraction, on velocity, temperature and microrotation profiles and components. Also, the use of mixed base fluids presented as a novelty in this paper.

The purpose of the study is to investigate the perceived stigma among residents of Sanandaj, west of Iran, following COVID-19 pandemic.

This is a cross-sectional study conducted from March to April 2020. The sample consisted of 1,000 participants who live in Sanandaj. The data collection tool was a self-report electronic questionnaire. ANOVA and T-test were used to analyze the data.

The mean perceived stigma for COVID-19 was 5.50±2.24 (IQR: 3.75–6.87) out of 10-point scale. The highest point was seen for perceived external stigma (6.73±2.49, IQR: 5–8.75) followed by disclosure stigma (4.95±3.92, IQR: 0–10). Interestingly, self-employers were more concerned about disclosing their illness than those with governmental jobs (25±3.93 vs. 4.31±4.14, P<0.05), and also had an overall higher stigma score; 5.72±2.23 vs. 5.19±2.37, P<0.05).

COVID-19 stigma is high among Iranians and more common among men, youngsters and self-employers.

Thinking and deciding about the future of the city as a combination of complex and uncertain systems is extremely difficult. This complexity, uncertainty and difficulty will be increased when our thoughts and decisions address the city’s long-term future. Considering these issues, the need for future thinking and alternate thinking in the process of urban management and planning becomes even more necessary. The purpose of this paper is to identify and explain the alternate futures of Tehran.

For this purpose, this study have tried to study alternate future images of Tehran in an archetypal form of “growth, collapse, disciplined society and transformed society” using “Dator’s Four Generic Alternate Futures” method.

These alternate futures, after identifying their key trends and drivers, have been narrated in the form of four scenarios called: “capital business center,” “crossing the fate of ray,” “Tehran family” and “Tehran investigators.” Increasing the authority and responsibility of the local governance, modification of Tehran urban management model and development of voluntary cooperation and democratic participation, are among the policy recommendations made on the basis of these images.

Achieving these images in parallel with identifying the most important challenges and opportunities in alternate futures will provide the basis for policy-making in Tehran’s future urban governance. It can be a creative model for developing future images for other cities.