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BACKGROUND: Little is known about the association between active commuting (i.e., walking or cycling to school) with lifestyle parameters and mental health in youths. The objective of the present study was to investigate the association between mental health problems and symptoms of depression, anxiety, and stress with lifestyle (i.e., food habits, screen time, physical activity, and sleep quality), active commuting, and gender. METHODS: A total of 511 children and adolescents (boys, n = 249; girls, n = 262) aged 10 to 17 years participated in the study. Lifestyle parameters and mental health were evaluated using the Depression Anxiety and Stress Scale (DASS-21). RESULTS: Girls reported higher levels of anxiety (p = 0.001), depression (p = 0.001), and stress (p = 0.001). Mental health problems showed a positive association with gender (girls, ß = 3.06, p < 0.001) and a negative association with food habits (ß = -0.65, p = 0.019). Anxiety was positively associated with gender (ß = 7.88, p < 0.001) and negatively associated with food habits (ß = -0.23, p = 0.019). Gender (girls) and food habits were also associated with symptoms of depression (ß = 2.29, p < 0.001 and ß = -0.27, p = 0.005, respectively). Finally, active commuting was inversely associated with stress (ß = -1.24, p = 0.008), and stress was positively linked to gender (ß = 2.53, p < 0.001). CONCLUSIONS: Active commuting, lifestyle parameters, and gender were associated with mental health in children and adolescents. Moreover, girls reported higher levels of anxiety, symptoms of depression, and stress.

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The United Nations, through its 2030 Agenda and Sustainable Development Goals, advocates for the establishment of conducive environments for physical activity, following the ecological model. In line with this initiative, active transportation emerges as an accessible, cost-effective, and sustainable approach to augmenting daily physical activity levels. This study protocol endeavors to assess the impact of an active transportation education program rooted in the ecological model on the physical and mental well-being of high school students. Drawing upon scientific insights, we hypothesize that a 16-week active transportation intervention will lead to a 3% reduction in average body fat percentage and a noteworthy enhancement in executive function (including inhibition, cognitive flexibility, and working memory), physical fitness (comprising cardiorespiratory fitness and muscle strength), and mental health (encompassing mood disorders and cognitive functioning). If this intervention proves effective, it could offer a viable solution for the school community, especially in reducing congestion within the school environment. The study protocol aims to evaluate the impact of an active transportation educational program based on the ecological model on the physical and mental well-being of high school students. Three high schools located in the urban area of Talca, Chile, will be randomly selected (one public, one privately subsidized, and one private non-subsidized). Each high school will be randomly assigned an experimental group (n = 30) and a control group (n = 30; without intervention). The experimental groups will receive an active transportation educational intervention during their physical education classes for four months (60 to 90 min sessions, once a week), while the control group will receive no intervention. The primary outcome will provide information on body composition and executive function. Secondary outcomes will include objective physical activity level, physical fitness, mental well-being, academic achievement, health-related quality of life, perception of environmental urban features, physical activity barriers, and adherence to active transportation. It is expected that the results of the MOV-ES Project will transcend the physical health of schoolchildren and will have an impact on the school community, especially by decongesting the school environment.

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The protoscolex (PSC) is generated by asexual reproduction at the larval stage of taeniid Echinococcus granulosus that causes cystic echinococcosis or hydatidosis, a worldwide zoonosis. The PSC is enveloped by a complex cellular syncytial tegument responsible for ionic movements and the hydroelectrolytic balance of the parasite. We recently reported on two electrical potentials in bovine lung protoscoleces (PSCs) that reflect differences in ionic movements between the parasite's invaginated and evaginated developmental stages. Here, we explored the effect of temperature and ionic substitutions on the tegumental potentials of bovine lung PSCs of Echinococcus granulosus by microelectrode impalements. We observed that the transient peak potential was temperature-dependent, consistent with an active transport component in the invaginated state only. Further changes in the electrical potentials by high K+ depolarization, low external Ca2+, and addition of the diuretic amiloride are in agreement with the presence of a Ca2+-sensitive cation-selective electrodiffusional pathway in the outer surface of the parasite. Variations in electrical potential differences through the tegument provide an accessible and valuable parameter for studying ionic transport mechanisms and, therefore, potential targets for developing novel antiparasitic drugs.

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OBJECTIVE: To determine the effectiveness of structural-level environmental interventions on the changes in PA levels in the populations examined. METHODS: Natural experiments that involve environmental intervention with structural modification were included. The primary outcome PA levels with consideration of both objective and subjective measurements. An electronic search was carried out in Medline/Pubmed, SCIENCE DIRECT, WEB OF SCIENCE, and CINAHL up to January 2022. Two reviewers screened titles and abstracts, selected studies, extracted relevant data, and examined study quality. A qualitative synthesis was performed. RESULTS: Twenty-six articles were included. The structural-level environmental interventions included 4 fundamental areas: schools, work environments, streets or cities, and neighborhoods or parks. Of the 26 studies, 21 examined outdoor environments like parks, cities, pedestrian walkways, or steps, while 5 examined indoor or closed environments like schools and workplaces revealing that structural-level environmental interventions improve PA levels with the greatest effect in parks and active transportation. A risk of bias is inherent in natural experiments which is a limitation of this study. In schools and work areas, there is evidence of both decrease in sedentary time and an increase in PA related to environmental modifications. CONCLUSION: Structural-level environmental modifications in parks and active transportation demonstrated greater effects in promoting PA. Environmental modifications can impact physical activity in the population. Given that the economic and cultural setting is a key variable when considering the effectiveness of structural interventions, and since only 1 of the 26 reviewed articles included such data, more studies examining economic factors are needed especially in low- and middle-income countries like in South America. TRIAL REGISTRATION: PROSPERO CRD42021229718.

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Background and Objectives: Particulate Matter (PM), particles of variable but small diameter can penetrate the respiratory system via inhalation, causing respiratory and/or cardiovascular diseases. This study aims to evaluate the association of environmental particulate matter (PM2.5) and black carbon (BC) with respiratory health in users of different transport modes in four roads in Bogotá. Materials and Methods: this was a mixed-method study (including a cross sectional study and a qualitative description of the air quality perception), in 300 healthy participants, based on an exploratory sequential design. The respiratory effect was measured comparing the changes between pre- and post-spirometry. The PM2.5 and black carbon (BC) concentrations were measured using portable devices. Inhaled doses were also calculated for each participant according to the mode and route. Perception was approached through semi-structured interviews. The analysis included multivariate models and concurrent triangulation. Results: The concentration of matter and black carbon were greater in bus users (median 50.67 µg m-3; interquartile range (-IR): 306.7). We found greater inhaled dosages of air pollutants among bike users (16.41 µg m-3). We did not find changes in the spirometry parameter associated with air pollutants or transport modes. The participants reported a major sensory influence at the visual and olfactory level as perception of bad air quality. Conclusions: We observed greater inhaled doses among active transport users. Nevertheless, no pathological changes were identified in the spirometry parameters. People's perceptions are a preponderant element in the assessment of air quality.

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Abstract This study aimed to analyze the association between the practice of different types of physical activity (PA) with perceived environmental factors in boys and girls adolescents. Were evaluated 1,130 adolescents from Porto Alegre, Brazil. To evaluate different PA, students answered whether or not they practiced walking, running, team sports, and others general PA. Perceived environmental factors were assessed through Neighborhood Environment Walkability Scale for Youth (NEWS-Y). Analyses were performed using logistic regression. Adolescents who reported perceiving a distance up to 20 minutes to walking/running track, had their chances of practicing all types of PA increased in the total sample and for girls. For walking, it was also found an association with access in adolescents. For girls, it was found an association between shortest distance to indoor recreation or exercise facility and other playing fields/court with running and team sports. Aesthetics and road safety were associated with team sports in adolescents. Other general PA were associated with park, bike/hiking/walking trails in the total sample and for girls. Therefore, for each type of PA, specific associations of perceived environmental factors were found.

Resumo Este estudo teve como objetivo analisar a associação entre a prática de diferentes tipos de atividade física (AF) com fatores ambientais percebidos em meninos e meninas adolescentes. Foram avaliados 1.130 adolescentes de Porto Alegre, Brasil. Para avaliar diferentes AF, os alunos responderam se praticavam ou não caminhada, corrida, esportes coletivos e outras AF em geral. Fatores ambientais percebidos foram avaliados pelo Neighborhood Environment Walkability Scale for Youth. As análises foram realizadas por meio de regressão logística. Adolescentes que relataram perceber uma distância de até 20 minutos para pista de caminhada/corrida tiveram suas chances de praticar todos os tipos de AF aumentadas na amostra total e para as meninas. Para caminhada, também foi encontrada associação com o acesso em adolescentes. Para as meninas, foi encontrada uma associação entre a menor distância para instalações de exercícios e outros campos de jogos/quadra com corrida e esportes coletivos. A estética e a segurança de ruas foram associadas com esportes coletivos em adolescentes. Outras AF gerais foram associadas com parque e trilhas de bicicleta/caminhada na amostra total e para meninas. Portanto, para cada tipo de AF, foram encontradas associações específicas de fatores ambientais percebidos.

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The main objective of the current study was to analyze how parents' sociodemographic characteristics, mode of commuting and physical activity (PA) act as indicators of active commuting to school (ACS) in their children and adolescents. A total of 684 paired parents (52.8% mothers) and their respective offspring (33.7% girls) were included. The participants self-reported their sociodemographic characteristics, mode of commuting, and PA. Logistic regression analyses were performed using a stepwise approach, including, as indicators, parental characteristics, mode of commuting and PA. The main outcome was child and adolescent ACS. The odds ratio (OR) and R2 of Nagelkerke were obtained for each step. Parental sociodemographic characteristics were greater indicators of child ACS than the parental mode of commuting and PA. In children, the greatest predictive variables of ACS explained 38% of the variance and were as follows: car availability (OR = 0.24), father's educational level (OR = 0.47), mother's educational level (OR = 1.95), mother's active commuting to work (OR = 4.52) and mother's salary/month (OR = 0.67). In adolescents, the greatest predictive variables of ACS explained 40% of the variance and were as follows: socioeconomic level (OR = 0.43) and father's active commuting (OR = 10.6). In conclusion, sociodemographic factors are better indicators of ACS than parents' physical activity and active commuting to work.

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Abstract The purpose of this study is to determine the factors associated with negative self-rated health in Brazil. The sample consisted of 5,259 adults from five representative capitals of the five regions of Brazil. Data collection was achieved in the following municipalities: Palmas (North Region), João Pessoa (Northeast Region), Goiânia (Central-West Region), Vitória (Southeast Region) and Florianópolis (South Region). For the analysis of the data, Binary Logistic Regression for determine the factors associated with negative self-rated health was used. Negative self-rated health was identified in 31.43% of Brazilians. The factors that were significantly associated were bad air quality, does not have public spaces for leisure, older age group, insufficient salary to cover expenses, a rare practice of physical exercises, does not perform healthy eating, active commuting for study or employment and commuting time for above 30 minutes, dissatisfaction with health services and still, not working, not looking for a job and finally, reside in some Brazilian regions. The study presents the importance of socioenvironmental and behavioral factors for the self-rated health of Brazilian adults, as well as it shows high rates of negative self-rated health compared to other studies.

Resumo O objetivo deste estudo foi determinar os fatores associados à percepção negativa de saúde no Brasil. A amostra foi composta por 5.259 adultos de cinco capitais representativas das cinco regiões do Brasil. A coleta de dados foi realizada nos seguintes municípios: Palmas, João Pessoa, Goiânia, Vitória e Florianópolis. Para analisar os dados, utilizou-se da Regressão Logística Binária para determinar os fatores associados. Identificou-se percepção negativa de saúde em 31,43% dos brasileiros. Os fatores que foram significativamente associados foram: má qualidade do ar, não possuir espaços públicos de lazer, faixa etária mais avançada, salário insuficiente para cobrir despesas, prática rara de exercícios físicos, não realizar alimentação saudável, deslocamento ativo para estudo ou emprego, tempo de deslocamento acima de 30 minutos, insatisfação com os serviços de saúde, não trabalhar e não estar procurando emprego e, por fim, residir nas regiões Sul, Sudeste e Nordeste do Brasil. O estudo apresenta a importância de fatores socioambientais e comportamentais para a percepção da saúde de adultos brasileiros e mostra altos índices de percepção negativa de saúde em comparação com outros estudos.

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BACKGROUND: Independent mobility (IM) provides young people with many opportunities to increase their autonomy and physical activity (PA). This study aimed to analyse whether the parent's PA, active commuting to work and sociodemographic factors serve as predictors of IM to school in children and adolescents. METHODS: A total of 684 parents (52.8% mothers) and their offspring (56.4% girls) were included in this study, which was performed in Granada (Spain) and Valparaíso (Chile). The parents self-reported their sociodemographic characteristics, PA and mode of commuting to work. The mode of commuting to and from school and the offspring accompaniment mode were reported. T-test and chi-square test were used to study quantitative and qualitative differences by parental gender, respectively. Binary logistic regression models (odds ratio = OR) and stepwise analysis were performed to study the association between the parents' sociodemographic variables and IM to school. RESULTS: Adolescents showed higher IM to school than children (58.9% vs 40.2%; p < 0.001). No car availability and shorter distance to work were positively associated with higher IM to school in children (OR = 2.22 and 2.29, respectively). Mothers' lower salary/month (OR = 2.75), no car availability (OR = 3.17), and mother passive commuting to work (OR = 2.61) were positively associated with higher IM to school in adolescents. The main predictor of IM to school in children and adolescents was no car availability (OR = 6.53). CONCLUSION: Parental sociodemographic factors, such as salary, distance to work and car availability, were associated more strongly with IM than parental PA and active commuting to work.

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Biking and walking are active commuting, which is considered an opportunity to create healthy habits. OBJECTIVE: The purpose of this study was to determine the main environmental and psychosocial barriers perceived by students, leading to less Active Commuting (AC) to university and to not reaching the Physical Activity (PA) recommendations. MATERIAL AND METHODS: In this cross-sectional study, 1349 university students (637 men and 712 women) were selected. A self-reported questionnaire was applied to assess the mode of commuting, PA level and barriers to the use of the AC. RESULTS: Women presented higher barriers associated with passive commuting than men. The main barriers for women were "involves too much planning" (OR: 5.25; 95% CI: 3.14-8.78), "It takes too much time" (OR: 4.62; 95% CI: 3.05-6.99) and "It takes too much physical effort " (OR: 3.18; 95% CI: 2.05-4.94). In men, the main barriers were "It takes too much time" (OR: 4.22; 95% CI: 2.97-5.99), "involves too much planning" (OR: 2.49; 95% CI: 1.67-3.70) and "too much traffic along the route" (OR: 2.07; 95% CI: 1.47-2.93). Psychosocial barriers were found in both sexes. CONCLUSIONS: Psychosocial and personal barriers were more positively associated with passive commuting than environmental barriers. Interventions at the university are necessary to improve the perception of AC and encourage personal organization to travel more actively.

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BACKGROUND: Some studies have reported a positive parent-child association between physical activity (PA), but few have examined the difference in these associations concerning both genders. The objective of this study was to establish the association between moderate to vigorous physical activity (MVPA) and mode of commuting (MC) of the parents with their children by gender and age group. METHODS: This cross-sectional study included 686 mothers and fathers (43.4 ± 6.5 years old) and their children (children 9.7 ± 1.7 y. and adolescents 14.0 ± 1.7 y.). Each participant completed a questionnaire on PA and MC. Chi-square test, odds ratio for categorical variables, and lineal regressions for continuous variables were used to examine the parent-child associations. RESULTS: An inverse association was found between fathers-children in the weekend MVPA in children and between mothers-adolescents in out-of-school and weekend MVPA. An inverse association was found in MVPA between mothers-girls, and the different parents' MC to work was positively associated with the MC to school in children and adolescents except for the association AC parents-adolescents. The AC was mainly associated between mothers and girls and boys. CONCLUSIONS: A weak association in parent-child MVPA but a strong association in MC between parent-child was found.

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According to the World Health Organization (WHO) air pollution in urban areas, mainly associated with inhalation of gaseous pollutants and particulate matter emitted from motor vehicles, is responsible for one million deaths per year. Carbon monoxide (CO) from the incomplete combustion of fuel is known to bind with hemoglobin, decreasing the blood oxygen-delivery and inducing tissues hypoxia; being more pronounced under conditions of stress like physical activity. The present study demonstrates the usefulness of a compact CO sensor (Alphasense CO-B4) mounted on a bicycle to evaluate atmospheric levels of CO associated with urban microenvironments within a growing Australian city (Brisbane). Urban bike pathways show pronounced and significant variations in air quality according to the surrounding microenvironment and the time of day. The inhaled dose in real time and the CO total dose over each trip were valuable for estimating the air quality of the route, and identifed how the health benefits of riding a bicycle could be partially offset by poor air quality depending on where and when a cycle route is taken in the inner-city. Finally, environmental conditions, such as wind speed, were found to significantly affected atmospheric CO concentrations, at least during the study period. The present work provides information regarding commuters' exposure to atmospheric pollutants, necessary for modifying the population's (including cyclists) perception of pollution in the urban environment, providing people with the opportunity to choose a healthier route.

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Multidrug resistance (MDR) in cancer arises from cross-resistance to structurally- and functionally-divergent chemotherapeutic drugs. In particular, MDR is characterized by increased expression and activity of ATP-binding cassette (ABC) superfamily transporters. Sphingolipids are substrates of ABC proteins in cell signaling, membrane biosynthesis, and inflammation, for example, and their products can favor cancer progression. Glucosylceramide (GlcCer) is a ubiquitous glycosphingolipid (GSL) generated by glucosylceramide synthase, a key regulatory enzyme encoded by the UDP-glucose ceramide glucosyltransferase (UGCG) gene. Stressed cells increase de novo biosynthesis of ceramides, which return to sub-toxic levels after UGCG mediates incorporation into GlcCer. Given that cancer cells seem to mobilize UGCG and have increased GSL content for ceramide clearance, which ultimately contributes to chemotherapy failure, here we investigated how inhibition of GSL biosynthesis affects the MDR phenotype of chronic myeloid leukemias. We found that MDR is associated with higher UGCG expression and with a complex GSL profile. UGCG inhibition with the ceramide analog d-threo-1-(3,4,-ethylenedioxy)phenyl-2-palmitoylamino-3-pyrrolidino-1-propanol (EtDO-P4) greatly reduced GSL and monosialotetrahexosylganglioside levels, and co-treatment with standard chemotherapeutics sensitized cells to mitochondrial membrane potential loss and apoptosis. ABC subfamily B member 1 (ABCB1) expression was reduced, and ABCC-mediated efflux activity was modulated by competition with nonglycosylated ceramides. Consistently, inhibition of ABCC-mediated transport reduced the efflux of exogenous C6-ceramide. Overall, UGCG inhibition impaired the malignant glycophenotype of MDR leukemias, which typically overcomes drug resistance through distinct mechanisms. This work sheds light on the involvement of GSL in chemotherapy failure, and its findings suggest that targeted GSL modulation could help manage MDR leukemias.

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The aim of this study was to investigate, in a well-controlled experimental environment, whether air pollution from an urban center would affect inflammatory and cardiorespiratory responses during prolonged moderate exercise (i.e., 90 min). Ten healthy men performed two experimental trials under filtered and polluted air, inside an environmental chamber located in Sao Paulo downtown, Brazil. Blood samples were obtained at rest, 30, 60, and 90 min of the exercise to determine the serum cytokines concentration, while arterial pressure was recorded immediately after the exercise. The serum cytokines were not altered until 60 min of exercise for both conditions (P > 0.05). Otherwise, at 90 min of exercise, the IL-6 (P = 0.047) and vascular endothelial growth factor (VEGF) (P = 0.026) were significantly higher and IL-10 tended to decrease (P = 0.061) in polluted air condition compared to filtered air condition. In addition, both systolic (P = 0.031) and diastolic (P = 0.009) arterial pressure were higher in polluted air condition than filtered air condition. These findings demonstrate that the exercise of longer duration (i.e., 90 min), but not of shorter duration (i.e., <60 min), performed in vehicular air pollution condition results in pronounced pro-inflammatory and increased arterial pressure responses.

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Background and Objectives: Active commuting to and from university (ACU) could be a strategy to increase physical activity levels (PA) and promote health in young university students. We aimed to a) examine the patterns of commuting to university in Chilean students; b) the association between the mode of commuting to and from university and socio-demographic factors and PA-levels. Materials and Methods: A total of 496 university students (21.6 ± 2.4 years old) from two universities from Valparaíso (central coast of Chile) participated in this study. Personal data, home address, socio-economic status, PA, and the usual mode of commuting to and from the university were self-reported by a questionnaire. The commute distances were objectively measured using Google-Maps-software. Associations were examined using binary logistic regressions. Results: The main mode of commuting was by bus (to university: 55.2% vs. from university: 59.3%; p < 0.001). The least used mode was cycling (1.4% to and from university). Students living >5-km from university were less active commuters than those living in closer distances: (2-5 km, odds ratio (OR): 4.424, 95% and 95% confidence intervals (CI): 2.443-8.011, p < 0.001; 2 km, OR: 143.052, 95% CI: 55.154-371.030, p < 0.001). Students with low PA-levels were less active commuters than those with medium (OR: 1.446; 95% CI: 0.864-2.421; p = 0.160) or higher levels (OR: 1.880; 95% CI: 1.880-1.094; p = 0.022). Students who lived between 2 and 5 km, presented a significant association to be active commuters when they showed medium PA-levels (OR: 5.244, 95% CI: 1.358-20.246; p = 0.016). Conclusions: Chilean university students from Valparaíso are mainly passive commuters using public transport as the main mode of commuting to and from university; longer distances from home to the university are associated with low PA levels. ACU in distances between 2-5 km (mainly walking) could contribute to having medium PA-levels in Chilean university students. Thus, promoting the ACU walking to and from the university in such distances could be an effective strategy to increase the overall PA levels in Chilean university students.

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Objective: To compare the differences in the modes and distance of the displacements in high school and university stage in the same sample. Methods: A total of 1288 volunteer university students (614 males and 674 females) participated, with an average age of 22.7 ± 5.8 years, belonging to four private and public universities in Chile where a validated self-report questionnaire was applied to the study, which included the modes, travel time, and distance at school and university. Results: The active commuting decreases from school to university when leaving home (males: 39.6% to 34.0%; p = 0.033 and females: 32.9% to 18.5%, p < 0.001), as well as when returning (males: 44.1% to 33.7%; p < 0.001 and females: 38.6% to 17.6%, p < 0.001). Conversely, non-active modes of transport increase, especially in females (go: 67.1% to 81.4%, return: 61.5% to 82.6%), affected by the increase in the use of public transportation in university. It was also defined that at both school and at university, the active commuting decreases the greater the distance travelled. Conclusion: The active modes of commuting decreased between high school and university and the non-active mode of commuting was the most frequent form of mobility to high school and university, observing that the active trips decreased when the distance from the home to high school or university increased. Public and private intervention policies and strategies are required to maintain or increase the modes of active commuting in the university stage for an active life in adulthood.

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BACKGROUND: There is limited evidence concerning how active commuting (AC) is associated with health benefits in young. The aim of the study was to analyze the relationship between AC to and from campus (walking) and obesity and metabolic syndrome (MetS) in a sample of Colombian university students. METHODS: A total of 784 university students (78.6% women, mean age = 20.1 ± 2.6 years old) participated in the study. The exposure variable was categorized into AC (active walker to campus) and non-AC (non/infrequent active walker to campus: car, motorcycle, or bus) to and from the university on a typical day. MetS was defined in accordance with the updated harmonized criteria of the International Diabetes Federation criteria. RESULTS: The overall prevalence of MetS was 8.7%, and it was higher in non-AC than AC to campus. The percentage of AC was 65.3%. The commuting distances in this AC from/to university were 83.1%, 13.4% and 3.5% for < 2 km, 2-5 km and > 5 km, respectively. Multiple logistic regressions for predicting unhealthy profile showed that male walking commuters had a lower probability of having obesity [OR = 0.45 (CI 95% 0.25-0.93)], high blood pressure [OR = 0.26 (CI 95% 0.13-0.55)] and low HDL cholesterol [OR = 0.29 (CI 95% 0.14-0.59)] than did passive commuters. CONCLUSIONS: Our results suggest that in young adulthood, a key life-stage for the development of obesity and MetS, AC could be associated with and increasing of daily physical activity levels, thereby promoting better cardiometabolic health.

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BACKGROUND: This study aims to describe the regional prevalence and patterns of physical activity (PA) and sedentary behavior among Brazilian adolescents. METHODS: Data from the Brazilian Scholar Health Survey, a nationally representative survey of ninth-grade adolescents [mean age: 14.29 y (14.27-14.29)] conducted in 2015 (n = 101,445), were used. Outcomes were television viewing, sitting time (ST), total PA, and active traveling collected via self-administered questionnaire. Information on frequency of physical education classes and type of school was collected from the school's director. Frequencies with 95% confidence intervals were used to determine the prevalence and patterns of outcomes. RESULTS: Higher prevalence of PA (≥300 min/wk) and ST (>4 h/d) was found in Midwest (PA = 38.0%; ST = 44.5%), South (PA = 37.6%; ST = 50.1%), and Southeast (PA = 36.1%; ST = 49.3%) compared with Northeast (PA = 29.7%; ST = 36.9%) and North (PA = 34.4%; ST = 34.8%) regions of Brazil. ST was higher among adolescents from private schools (51.5%) than public schools (42.9%), whereas active traveling was greater among students of public schools than private schools (62.0% vs 34.4%). Most inequalities in outcomes between capital and interior cities were in the poorest regions. CONCLUSIONS: The results indicate that national plans targeting regional inequalities are needed to improve PA and to reduce sedentary behavior among Brazilian adolescents.

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A general formulation for both passive and active transmembrane transport is derived from basic thermodynamical principles. The derivation takes into account the energy required for the motion of molecules across membranes and includes the possibility of modeling asymmetric flow. Transmembrane currents can then be described by the general model in the case of electrogenic flow. As it is desirable in new models, it is possible to derive other well-known expressions for transmembrane currents as particular cases of the general formulation. For instance, the conductance-based formulation for current turns out to be a linear approximation of the general formula for current. Also, under suitable assumptions, other formulas for current based on electrodiffusion, like the constant field approximation by Goldman, can be recovered from the general formulation. The applicability of the general formulations is illustrated first with fits to existing data, and after, with models of transmembrane potential dynamics for pacemaking cardiocytes and neurons. The general formulations presented here provide a common ground for the biophysical study of physiological phenomena that depend on transmembrane transport.

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The current study examined the relationship between cognitive performances (executive function, selective attention and reaction time), fine motor coordination skills and perceived difficulty after active transport to school. Method: Fifteen right-handed children's underwent session, 15-min walking session at 30% (WS1) and 15-min walking session (WS2) at 50% of maximal aerobic speed. Subjects performed tests to evaluate executive function, reaction time and selective attention. After each trial, a questionnaire of perceived difficulty (PD) was completed. Results: Average time in TMT part A (F(2,22) = 4.44; p = 0.024; η2= 0.288) and TMT part B (F(2,22) = 4.54; p = 0.022; η2= 0.292), and committed errors (F(2,22) = 7.78; p = 0.003; η2= 0.414) was improved after walking sessions in comparison by CS. The mean scores were significantly higher after walking sessions for both long and short-distance throws (p < 0.05). Moreover, a significant negative correlation was found between committed errors (TMT part B) and both dart throwing consistency and accuracy (r = - 0.6; r = - 0.64; p < 0.05) (respectively). Post-hoc analysis showed that PD was better after walking sessions with low intensity for both short and long throwing distance. However, it seems that walking session with sustained intensity allows speed and accuracy improvement of cognitive processing. Conclusion: Thus, active walking to school with low intensity was sufficient to produce positives changes in psychomotor performance and decrease in perceived difficulty scores. By including individual differences in gross motor coordination as well as physical activity level, the exact nature of the link between psychomotor skills and cognitive performance could be more addressed.(AU)

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