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The purpose of this study is to model and solve numerically the three-dimensional off-centered stagnation point flow and heat transfer of magnesium oxide–silver/water hybrid nanofluid impinging to a spinning disk.

The applied effective thermophysical properties of hybrid nanofluid including thermal conductivity and dynamics viscosity are according to the reported experimental relations that would be expanded by a mass-based algorithm. The single phase formulations coupled with experimental-based hybrid nanofluid model is implemented to derive the governing partial differential equations which are then transferred to a set of dimensionless ordinary differential equations (ODEs) with the use of the similarity transformation method. Afterward, the reduced ODEs are solved numerically by bvp4c function from MATLAB that is a trustworthy and efficient code according to three-stage Lobatto IIIa formula.

The effect of spinning parameter and nanoparticles masses (m_MgO, m_Ag) on the hydrodynamics and thermal boundary layers behavior and also the quantities of engineering interest are presented in tabular and graphical forms. The recent work demonstrates that the analysis of flow and heat transfer becomes more complicated when there is a non-alignment between the impinging flow and the disk axes. From computational results demonstrate that, the radial and azimuthal velocities are, respectively, the increasing and decreasing functions of the disk spinning parameter. Further, for the greater values of the spinning parameter, an overshoot of the radial velocity owing to the centrifugal forces of the spinning disk is observed. Besides, the quantities of engineering interest gently enhance with first and second nanoparticle masses, while comparing their absolute values illustrates the fact that the effect of second nanoparticle mass (m_Ag) is greater. Further, it is inferred that the second nanoparticle’s mass enhancement results in the amplification of the heat transfer; although, the high skin friction and the relevant shear stress should be controlled.

The combination of experimental thermophysical properties with theoretical modeling of the problem can be the novelty of the present work. It is evident that the experimental relations of effective thermophysical properties can be trustable and flexible in the theoretical/mathematical modeling of hybrid nanofluids flows. Besides, to the best of the authors’ knowledge, no one has ever attempted to study the present problem through a mass-based model for hybrid nanofluid.

This paper aims to analyze the accuracy of the single and two-phase numerical methods for calculation of ferrofluid convective heat transfer in the presence of a magnetic field. The findings of current study are compared with previous single-phase numerical results and experimental data. Accordingly, the effect of various parameters including nanoparticles concentration, Reynolds number and magnetic field strength on the performance of the single and two-phase models are evaluated.

A two-phase mixture numerical study is carried out to investigate the influence of four U-shaped electromagnets on the hydrodynamic and thermal characteristics of Fe₃O₄/Water ferrofluid flowing inside a heated channel.

It is observed that the applied external magnetic field signifies the convective heat transfer from the channel surface, despite local reduction at a few locations. The maximum heat transfer enhancement is predicted as 23% and 25% using single and two-phase models, respectively. The difference between the results of the two models is mainly attributed to the slip velocity effect which is accounted for in the two-phase model. The magnetic field gradient leads to a significant increase in the slip velocity which in turn causes a slight difference in velocity and temperature profiles obtained by the single and two-phase models in the magnetic field region. According to percentage error calculation, the two-phase method is generally more accurate than the single-phase method. However, the percentage error of both models improves by decreasing either magnetic field intensity or Reynolds number.

For the first time in the literature, to the best of the authors’ knowledge, the current work analyzes the accuracy of the single and two phase numerical methods for calculation of ferrofluid convective heat transfer in the presence of a magnetic field.

The purpose of this paper is to examine the non‐communicable disease (NCD) known as gestational diabetes mellitus (GDM). Specifically, this paper aims to examine the influence of NCDs on health outcomes both worldwide and throughout the Islamic Republic of Iran, to discuss the current issues surrounding GDM and its impact on pregnant women and their children, and to present a new multi‐faceted approach for preventing future occurrences of GDM.

The paper examines the current issues surrounding NCDs and GDM, in terms of its prevalence and risk factors, and the efforts taken by the Iranian government to address the growing problem of GDM, through a comprehensive literature review. Further, this paper presents the basis for a new multi‐faceted approach for addressing and preventing GDM.

GDM is an NCD that can damage the health of both mothers and children. The disease has been linked to macrosomia, congenital cardiac and central nervous system abnormalities, and skeletal muscle deformities among neonates. Pregnant women who develop GDM are more likely to have induced labor, require caesarean section, and develop type 2 diabetes later in life. In the most severe cases, GDM can even result in fetal and maternal mortality. Worldwide prevalence of GDM varies by country, but Iranian women are a particularly high‐risk population. In fact, approximately one of every 20 pregnancies in Iran will be affected by complications and outcomes related to GDM.

In response to growing concerns surrounding the current prevalence of GDM both worldwide and within the Islamic Republic of Iran, along with the associated impact of GDM on health outcomes, the paper presents a multi‐faceted approach for addressing this NCD. This approach will involve a consolidated program of prevention and control with a focus on health‐care solutions which promote both awareness and education.

The purpose of this paper is to describe how formal verification strategies have been utilized to assess the correctness of Knowledge Creation Process (KCP) in the social systems. This paper analyzes a User Relationship Management (URM) approach in term of human behavior connection in the social systems. A formal framework is displayed for the URM which consolidates behavioral demonstrating strategy.

Evaluating the human behavior interactions is an important matter in the social systems. For this analysis, formal verification is an essential section in the complex information systems development. Model checking results satisfied the logical problems in the proposed behavior model analysis.

Model checking results represent satisfaction of the logical problems in the proposed behavior model analysis. In the statistical testing, the proposed URM mechanism supported KCP conditions. Also, the percentage of state reachability in the URM with KCP conditions is higher than the URM mechanism without supporting KCP conditions.

The model checking results show that the proposed URM mechanism with supporting the KCP conditions satisfies comprehensively behavioral interactions rather than the mechanism without KCP conditions in the social networks.

The purpose of this paper is to carry out a comprehensive review of some latest studies devoted to natural convection phenomenon in the enclosures because of its significant industrial applications.

Geometries of the enclosures have considerable influences on the heat transfer which will be important in energy consumption. The most useful geometries in engineering fields are treated in this literature, and their effects on the fluid flow and heat transfer are presented.

A great variety of geometries included with different physical and thermal boundary conditions, heat sources and fluid/nanofluid media are analyzed. Moreover, the results of different types of methods including experimental, analytical and numerical are obtained. Different natures of natural convection phenomenon including laminar, steady-state and transient, turbulent are covered. Overall, the present review enhances the insight of researchers into choosing the best geometry for thermal process.

A comprehensive review on the most practical geometries in the industrial application is performed.

This paper aims to evaluate the prevalence of general obesity (GO) and abdominal obesity (AO) in the north-west of Iran and investigate the association with food choices and socioeconomic status (SES).

In this cross-sectional study, 500 subjects aged ≥ 18 years were studied. Data on their basic characteristics, anthropometric measurements, dietary habits and physical activity were collected. The authors examined the association between GO and AO with SES and food choices using multiple logistic regression analysis.

The prevalence of GO and AO was 26.6 and 43.4%, respectively. A positive association was observed between age and GO (p for trend <0.001) and AO (p for trend 0.005) in both sexes. However, a negative correlation was detected between education and income with GO and AO (p for trend <0.001). Two or more servings of fruit consumption a day were associated with lower odds of obesity. It was observed that the odds of GO and AO decreased by three or more servings of daily fruit. The consumption of dairy products in two or more servings a day led to a reduction in odds of GO and AO. The consumption of five or more servings of legumes, beans and nuts a week was associated with lower odds of GO and AO.

Educational attainment, greater income and a higher intake of some specific food groups were associated with lower odds of obesity in the area. More population-based investigations are required to develop effective preventive strategies to control the status of being overweight and obesity in different regions.

Clinical evidence has suggested that alpha-lipoic acid (ALA), a potent antioxidant, seems to have some effects on inflammatory process. However, these results are equivocal. The purpose of this paper is to investigate the nature of association between ALA and serum C-reactive protein (CRP) level by pooling the results from clinical trial studies.

Relevant studies were identified by systematic literature search of PubMed/MEDLINE, Scopus, Web of Sciences and Cochrane library up to September 2016 for randomized controlled trials (RCTs) evaluating the impact of ALA supplementation on CRP. The pooled data were summarized as weighted mean difference (WMD) and 95 per cent confidence interval (CI). Effect sizes of eligible studies were pooled using random- or fixed-effects (the DerSimonian–Laird estimator) depending on the results of heterogeneity tests.

Of 212 papers, 15 were eligible RCTs according to inclusion criteria. The selected studies comprised 1,408 cases and 457 controls. The dose of ALA supplement ranged from 300 to 1,200 mg, and the duration of follow-up was from 1 to 48 weeks. ALA supplementation significantly reduced the levels of circulating CRP (WMD: −0.088, 95 per cent CI: −0.131, −0.045, p < 0.001) with significant heterogeneity (I² = 73.4 per cent, p < 0.001). Populations with age younger than 50 years (PMD: −0.060 mg/dl), receiving doses less than 600 mg/day (PMD: −0.057 mg/dl), having cardiovascular disease (PMD: −0.105 mg/dl), hemodialysis (PMD: −0.209 mg/dl), diabetes (PMD: −0.021 mg/dl) and otherwise healthy subjects (PMD: −0.045 mg/dl) were sources of heterogeneity.

This meta-analysis of RCTs suggests that ALA supplementation seems to significantly reduce circulating CRP level.