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The COVID-19 pandemic has caused significant mortality and morbidity worldwide. However, the role of dietary patterns as a potential risk factor for COVID-19 has not been well established, especially in studies with large samples. Therefore, this study aims to identify and evaluate the association between major dietary patterns and COVID-19 among adults from Iran.

In this cross-sectional study, the authors included 9,189 participants aged 20–70 who participated in the Yazd Health Study (YaHS) and Taghzieh Mardom-e-Yazd study (TAMIZ). They used factor analysis to extract dietary patterns based on a food frequency questionnaire (FFQ). Then, they assessed the relationship between these dietary patterns and the odds of COVID-19.

This study identified two major dietary patterns: “high protein and high fiber” and “transitional”. Participants in the highest tertile of the “high protein and high fiber” dietary pattern, which included vegetables, fruits, dairy and various kinds of meats such as red meat, fish and poultry, had a lower odds of COVID-19 compared with those in the lowest tertile. However, the “transitional” dietary pattern did not affect the risk of COVID-19.

In conclusion, a “high protein, high fiber” diet may lower the odds of COVID-19. This study suggests that dietary patterns may influence the severity and spread of future similar pandemics.

Dietary intake is a modifiable risk factor for metabolic syndrome (MetS). Therefore, this study aims to evaluate the association between the Healthy Eating Index-2015 (HEI-2015) and MetS.

MetS was diagnosed among 2,326 adults. Dietary intake was assessed by a validated food frequency questionnaire. The HEI-2015 was administered to assess the diet qualities. Multivariate logistic regression was also used to evaluate the relationship of HEI-2015 with MetS and its components.

The odds of MetS was lower in women who were in the third quintile of HEI-2015 compared with those in the first quintile after adjusting for age and energy intake (OR: 0.62, CI: 0.41 to 0.93). In addition, moderate adherence to HEI-2015 reduced the odds of high fasting blood glucose levels in both men and women (OR men: 0.30, CI: 0.11 to 0.85 OR women: 0.34, CI: 0.14 to 0.79). However, these relations were not linear. Adherence to HEI-2015 had no significant relationship with the prevalence of MetS and its components in the whole population.

A significant relationship was observed between moderate adherence to HEI-2015 and fasting blood glucose in both men and women. Moreover, moderate adherence to this dietary pattern decreased the prevalence of MetS in women.

Established data revealed a relationship between obesity and increasing the risk of mortality and morbidity of chronic diseases. There are conflicting data regarding the association between adherence of dietary approach to stop hypertension (DASH) and obesity. Therefore, this study aims to investigate this relationship among a large sample of Iranian adults.

This cross-sectional study was performed by 10,693 individuals; 6750 individuals related to Yazd Health Study living in the urban area and 3943 individuals related to Shahedieh cohort study living in the suburb area. Dietary intake was evaluated by using a validated food frequency questionnaire. In all participants, anthropometric indices including body mass index were measured. The DASH score was considered using gender-specific quintiles of DASH items. To evaluate the relationship of DASH diet and obesity, multivariate logistic regression analysis was used.

By adjusting confounders, participants in highest quintiles of DASH diet were compared to the lowest have lower odds of obesity in suburb area (odds ratio [OR]: 0.78; 95% confidence interval [CI]: 0.63, 0.96), in urban (OR: 0.71; 95% CI: 0.52, 0.99) and in whole population of both studies (OR: 0.75; 95% CI: 0.63, 0.90). Besides, more compliance of women to this diet in urban (OR: 0.64; 95% CI: 0.48, 0.85) and population of both studies (OR: 0.77; 95% CI: 0.62, 0.96) were associated with reduced odds of central obesity.

Considering this study limitations, the following can be mentioned: in this cross-sectional study, the causal relationship between DASH diet and obesity could not be assessed. Consequently, further prospective studies are required in this area. Second, although a valid food frequency questionnaire was used, but there was a measurement error and an error in the classification of people participating in the study. Moreover, we cannot reject the possibility of residual confounding bias because unknown or unmeasured confounders may exist that affected our results. Finally, our participants with odds of obesity might have been advised to reduce their fat intake, which led them to alter their dietary habits. However, such possibility cannot be resolved in a cross-sectional study.

DASH dietary pattern could decrease odds of obesity in both urban and suburb area and central obesity in urban area only. Further prospective studies are needed for causal conclusion.

This paper's purpose is to deal with single point and multipoint optimization of an airfoil. The aim of the paper is to discuss optimization in several design points (multipoint optimization) and compare the results with those of optimization at a specified design point.

A gradient‐based method is adopted for optimization and the flow is governed by two dimensional, compressible Euler equations. A finite volume code based on unstructured grid is developed to solve the equations.

Two test cases are studied for an airfoil with initial profile of NACA0012, with two types of design variables. And at the end a multi‐point case is presented.

The advantage of this technique over the other gradient‐based methods is its high‐convergence rate.

This research aims to investigate numerically the influence of braking jets on separation process of a flying object.

The flying object is at supersonic regime and axial separation of its stages is accomplished with the aid of braking jets of separated stage. The simulation is three‐dimensional and relative motion of the stages is considered three degree of freedom. Full Navier‐Stokes equations in conjunction with κ−ε (RNG) turbulence model equations are considered as governing equations. These equations are solved using the finite volume technique. The separation process is analysed as an unsteady process and the problem is solved in a moving grid domain. The local remeshing method is adapted to regenerate computational cells around moving boundaries.

Time history of flow field around the vehicle components, time history of aerodynamic coefficients, and instantaneous relative position of the body components are the results of this research. Numerical modelling results are compared with the results of other references.

Most of the similar works in this area have used Euler or thin layer Navier‐Stokes (TLNS) equations as governing equations and the use of full Navier‐Stokes equations to analyse such a complicated problem (3D axial separation with braking jets) have not been reported in the literature. Since there are some recirculation zones inside the flow field and Euler or even TLNS equations cannot predict their behaviours, the use of full Navier‐Stokes equations may lead to more accurate prediction of these regions and aerodynamic forces.