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The purpose of this paper is to investigate the hydromagnetic third-grade non-Newtonian fluid flow and heat transfer between two coaxial pipes with a variable radius ratio.

To solve the approximate nonlinear and linear problems with variable coefficients, a trial function was applied. Methods include collocation, least square and Galerkin that can be applied for obtaining these coefficients.

It is revealed that an increase of the non-Newtonian parameter, Hartmann number, and radius ratio leads to an augmentation of the absolute value of the dimensionless velocity, temperature, velocity gradient, and temperature gradient of about 10-60%. Further, the augmentation of Bi₁ reduces the absolute value of the dimensionless temperature profile and dimensionless temperature gradient about three to four times; hence, the dimensionless heat transfer rate reduces. However, the growth of Bi₂ has a contrary impact. Besides, the increase of Pr and Ec leads to an increase in the dimensionless temperature profile and dimensionless temperature gradient; therefore, the dimensionless heat transfer rate increases.

The convection heat transfer on the walls of the pipes is considered, and the nonlinear coupled momentum and energy equations are solved using the least squared method and collocation methods, respectively.

The study's main objective is to evaluate the morphological developments in the characteristics of the spatial configurations of the residential layouts in Kerman, Iran, in examining the impact on the level of visual privacy through the spectrum of permeability and wayfinding in space syntax analysis.

In this paper, plan graph analysis is used to measure the syntactic properties of seven topological residential architecture plans in Kerman, Iran, built from the 1970s to 2010s. The methodology involves the development of mathematical measurements to signify permeability and simulation of visibility graph analysis (VGA) to indicate wayfinding.

The findings reveal the residential layouts of Iranian houses tend to be less integrated over decades of design development from the 1970s to 2010s. Reduction in spatial integration corresponds to increase segregation allowing for enhanced visual privacy. The study underpins that, even with the constraints in the scale of the house and reduction in the number of nodes, as evident in the design of the modern residential layout, the efficient level of visual privacy is still achievable with regards to the standards demanded by the local culture.

The study examines the development in residential spatial configuration and building scale on visual privacy through a proposed methodology based on the level of permeability and wayfinding measured as a combined effect using the space syntax analysis and visual accessibility.

This study examines opinion leadership's personal and social characteristics to see which one is more effective in opinion leadership in four different industries: fashion, travel and tourism, wellness and book and literature. The specific subject of this investigation is how largely openness, exhibitionism and competence in interpersonal relationships and status and attitude homophily affect the opinion leadership and the decision-making of opinion leaders' followers.

The proposed model was tested with the questionnaire shared via stories featured on Instagram among followers of four micro-influencers in different industries. For the purpose of testing the offered hypotheses of this study, the partial least squares method was used.

The findings show that openness, exhibitionism and competence in interpersonal relationships have a substantial effect on opinion leadership. It was also evident that status and attitude homophily impact opinion leadership. The model supports the effect of both personal and social characteristics on opinion leadership; however, based on the results, the effect of personal characteristics on opinion leadership is more remarkable, both in a direct relationship and through the mediating role of para-social interaction.

This study is novel in categorizing opinion leaders' attributes in two different extents of personal and social characteristics. The authors defined a model of the effectiveness of each personal and social characteristic on opinion leaders. The model investigates whether the personal or social characteristics have the most effect on opinion leadership, particularly with the mediating role of para-social interaction.

Arnold Toynbee, the famous British historian and philosopher, argues that modern society should achieve a kind of universal peace in the new millennium. Toynbee asserts strongly that wars and culture clashes destroy the foundation of a civilization. He states: a comparative study of recognized civilizations all over the history shows that social destruction is a disaster whose secret hidden key could be found in the nature of war. In fact, principally, when a war is provoked by a civilization, it is also an independent cause for its destruction.

In the literature on peace and security, we identify at least two different uses of the term Eurasia. One stakes a rather narrow geographic boundary while the second includes a much broader region. If we adopt the narrower view, Eurasia incorporates the fifteen republics of the former Soviet Union and possibly their security zones in Eastern Europe. Choosing to see Eurasia more broadly means defining it as the huge land-mass that comprises the continents of Europe and Asia. We may call the narrower definition Eurasia Minor and the broader one Eurasia Major.

Rafis Abazov is an adjunct lecturer at the Harriman Institute at Columbia University, New York. He is the author of The Formation of Post-Soviet International Politics in Kazakhstan, Kyrgyzstan and Uzbekistan (1999), the Freedom House Report on Kyrgyzstan (2002 and 2003), the Historical Dictionary of Kyrgyzstan (2004), and Historical Dictionary of Turkmenistan, as well as numerous articles on economic and political development in Central Asia, Kazakhstan, Kyrgyzstan, and Turkmenistan. He has contributed articles to the Encyclopedia of Modern Asia, and the Encyclopedia of National Economies.

It is well accepted that diabetes is associated with heart diseases and hyperlipidemia as a risk factor. In traditional medicines, some herbs such as Aloe vera seem to be effective in controlling diabetes. Owing to lack of human studies, this study aims to examine the effect of Aloe vera consumption on fasting blood sugar (FBS), lipid profiles and body composition in type 2 diabetic patients.

This double-blind, placebo-controlled trial study was conducted in 2019, in Shiraz, Iran. A total of 56 diabetic subjects were randomized by block randomization to receive a daily supplement of 1,000 mg Aloe vera powder capsules (n = 28) or placebo (n = 28) for eight weeks. At baseline and after eight weeks of treatment, dietary intake and physical activity were assessed by three-day food recall and international physical activity questionnaire. Meanwhile, after an overnight fasting, FBS and lipid profiles were measured. Blood pressure and anthropometric parameters were assessed in the beginning and the end of the study. Independent t-tests were used for between-group analysis and paired t-tests for within-group analysis.

After intervention, weight, body mass index and waist circumference significantly decreased in comparison to the placebo group (p-value: < 0.001, 0.001 and 0.02). Although, FBS, total triglyceride and systolic blood pressure decreased significantly (p-value: 0.03, 0.001 and 0.01), no change has been seen in low density lipoprotein, high density lipoprotein and total cholesterol blood level and diastolic blood pressure.

The limitations of this study are the short study duration and lack of Aloe vera powder’s ingredient analysis.

This study is one of few human studies investigating the effect of Aloe vera on metabolic syndrome’s indices in diabetic patients. Because pharmacological therapy is tough, not comfort and correlated with potential adverse drug interactions, it is important to find an alternative or complementary measure to aid the diabetic patients. This study shows that Aloe vera has positive effect on body weight and blood sugar.

The main aim of this study is to investigate the mixed-mode I/II failure and the cracking manner of three-dimensional (3D)-printed components made by the fused deposition modeling technique in an experimental and theoretical manner.

Acrylonitrile butadiene styrene (ABS) material and a modified printing method (that increases the adhesion and integrity between the layers and strands) are used for manufacturing the semicircular bending (SCB) test samples. In addition to precracking, the effect of additional stress concentration on the stress field is studied by introducing three small holes to the SCB fracture samples. The critical mixed-mode I/II failure loads obtained from the experiments are predicted using different stress/strain-based fracture theories, including maximum tangential stress (MTS), maximum tangential strain (MTSN), generalized form of MTS and MTSN and combination of them with equivalent material concept (EMC). The effects of plastic deformation, as well as the structural stress concentration, are considered for a more realistic prediction of mixed-mode fracture load.

The stress-based criteria are more suitable than the strain-based theories. Among the investigated fracture models, the EMC–generalized maximum tangential stress theory provided the best agreement with the experimental results obtained from 3D-printed SCB tests.

The influences of stress risers and applicability of different failure theories in cracked layered 3D-printed parts are studied on the fracture behavior of tested specimens under mixed-mode I/II.