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This paper aims to study the extended trailing edge airfoil for a range of angle of attack at different intensities of turbulence.

In this paper, an experimental study on NACA 0020 airfoil with thin extended trailing edge modification of amplitude of h = 0.1c, 0.2c and 0.3c at the Reynolds number of 2.14 × 10⁵ are tested. The research was carried out for an angle of attack ranging from 0° = α = 35° for the turbulence intensity of 0.3%, 3%, 5%, 7% and 12%. From the experimental readings, the surface pressures are scanned using a Scanivalve (MPS2464) pressure scanner for a sampling frequency of 700 Hz. The scanned pressures are converted to aerodynamic force coefficient and the results are combined and discussed.

The airfoil with the extended trailing edge will convert the adverse pressure gradient to a plateau pressure zone, indicating the delayed flow separation. The CL value at higher turbulence intensity (TI = 12%) for the extended trailing edge over perform the base airfoil at the post-stall region. The maintenance of flow stability is observed from the spectral graph.

A thin elongated trailing edge attached to the conventional airfoil serves as a flow control device by delaying the stall and improving the lift characteristics. Additionally, extending the airfoil's trailing edge helps to manage the performance of the airfoil even at a high level of turbulence.

Distinct from existing studies, the presented results reveals how the extended trailing edge attached to the airfoil performs in the turbulence zone ranging from 0.3% to 12% of TI. The displayed pressure distribution explains the need for increasing trailing edge amplitude (h) and its impact on flow behaviour. The observation is that extended trailing edge airfoil bears to maintain the performance even at higher turbulence region.

The purpose of this study is to describe the prevalence of a sedentary lifestyle (<150 min of physical exercise/week) and associated factors of this behavior in Brazil.

An observational study was conducted through an online questionnaire in August–September 2020 (5.5 months after the beginning of the pandemic in the country). Socioeconomic, lifestyle, anthropometric, dietary and perceived stress data were evaluated as possible related factors to a sedentary lifestyle through multiple logistic regression analysis.

A total of 1,347 individuals were evaluated (median of 31 years old, 80.1% women), of whom 76.7% were considered sedentary. Associated factors to a sedentary lifestyle were being overweight; a greater difference between current weight and prepandemic weight; female sex; lower percentage of home-cooked meals; greater increase in the frequency of consumption of alcoholic beverages; higher frequency of consumption of cereals, sausages and sweets during the pandemic; and higher score of perceived stress.

To the best of the authors’ knowledge, no studies have aimed to reveal the associated factors to a sedentary lifestyle during the COVID-19 pandemic in Brazil. Protective factors against a sedentary lifestyle were eating breakfast, being a student, living with parents, a higher frequency of fruit consumption, a higher rate of alcohol consumption and a higher cognitive restriction of food intake during the pandemic. Most of the study participants were sedentary, especially women. A sedentary lifestyle was associated with worse lifestyle/eating habits and stress. Such findings encourage an interdisciplinary approach because habits and lifestyle have numerous interferences.

This study aims to identify comfort food (CF) consumption and its associated factors during the pandemic period. The study also involves an online survey conducted five months after the quarantine started in Brazil.

Data on lifestyle, eating habits and anthropometric data were collected before and during the pandemic, and the differences in these habits were analyzed. Univariate and multivariate logistic regression models were performed to identify predictors of CF consumption by gender.

A total of 1,363 individuals were included in the sample, with a median age of 31 years old, of whom 80.3% were women. Since individuals were free to respond about the food consumed without predetermined categories, it was possible to carry out a faithful assessment of the occurrence of this behavior. At the same time, allowing the subjectivity and symbolism inherent to the concept of CF to be embraced. CF consumption was present for 54%, with “sweets” being the most mentioned group by both genders. The factors associated with CF consumption in women during the pandemic were increased snacking, increased bread, candies and alcoholic beverage intake, increased time spent at work, worsened sleep quality, reduced meals, perceived stress (PS), emotional eating (EE), age and increased frequency of meat intake. In men, the predictors for CF consumption were remote full-time work/study, PS, EE and early waking time. For both genders, CF consumption during the pandemic period was associated with PS and EE.

This study provides an important overview of the possible contributions of the pandemic on behaviors and food choices related to the consumption of CF in Brazilians. This information is valuable to support further studies to investigate and treat the impacts of the pandemic on lifestyle, eating habits and behavior, mental health and other factors in the postpandemic period.