Plant species have been classified as being either heterobaric or homobaric based on the presence or absence (respectively) of bundle sheath extensions (BSE) in leaf veins. These leaf types differ in their physiological performance, and their occurrences tend to be associated with environment. This study investigated the presence/absence of BSE and their structural peculiarities in 49 woody species (28 angiosperm families) in the Brazilian Cerrado using anatomical methods. We measured the gas exchange indices and stomatal density. In addition to typical homobaric (61.2%) and heterobaric (22.4%) species, we also found species with intermediate BSE features. These we call “larger heterobaric” (12.2%) and “semi-heterobaric” (4.1%) species. In the former, BSE occurs around only the secondary veins, whereas in the latter the BSE projects only towards the adaxial leaf surface. The net CO2 assimilation rates, the stomatal conductance, the transpiration rates, and the carboxylation efficiencies were statistically higher in heterobaric than in homobaric species. In the larger heterobaric species, the photosynthetic indices were similar to those in the heterobaric species. Meanwhile, semi-heterobaric species showed photosynthetic indices similar to the homobaric species. We demonstrated that structural variation in the BSE is linked to physiological leaf performance, suggesting some correlation between leaf morphology and plant adaptations.

A Aprendizagem Baseada na Resolução de Problemas (ABRP)[1] é aliada na promoção de habilidades e competências mais típicas das ciências naturais, mesmo nos Anos Iniciais do Ensino Fundamental (AEIF). Investigamos a prática educativa de uma professora pedagoga em cooperação com licenciandos do curso de ciências biológicas, exclusivamente em aulas de ciências naturais, numa turma do 5º ano dos AIEF. Nossos objetivos principais consistiram em: (a) caracterizar a aula habitual conduzida pela pedagoga em ciências; (b) investigar a execução de práticas fundamentadas na ABRP voltadas ao ensino de ciências para alunos dessa faixa etária; e (c) analisar as principais percepções da docente participante sobre o uso da ABRP na sala de aula de ciências. Os resultados sugerem que professora e licenciandos perceberam a ABRP como potencial ferramenta favorecedora da aprendizagem para aulas de ciências, não apenas na apreensão de conteúdos científicos conceituais, mas de diferentes modos de fazer e compreender a ciência.   [1] Neste texto, optamos pela expressão Aprendizagem Baseada na Resolução de Problemas (ABRP), utilizada pelo grupo de portugueses coordenado por Vasconcelos et al (2012), que também se pautou, em seus estudos, em autores que investigaram a Problem Based Learning (PBL).

Although it is recognized that mental disorders are more likely to occur in adulthood, especially in university period, and result in damage to health and incapacity for work, researches with university population are scarce in Brazil. We aimed to evaluate the prevalence of Minor Mental Disorders (MMD) among undergraduate students of a public university of São Paulo state, and investigate its association with social and economic conditions, sexuality and gender. This is a cross-sectional study conducted in 2018 with 376 undergraduate students who were halfway through the course. Data were collected from an anonymously and self-administered questionnaire, and MMD was evaluated from Self Report Questionnaire (SRQ-20). Associations were estimated through logistic regression, and odds ration calculated. We found prevalence of 53.9% of MMD among the students, and associated with gender (OR, 3.66; 95% CI, 2.37-5.67), being LGBT + (e.g Bisexuals OR, 2.92; 95% CI, 1.56-5.50), not receiving necessary family support (OR, 5.6; 95% CI, 2.00 - 15.68), not being satisfied with the course (OR, 23.69 95% CI, 2.95 - 190,03) and not practicing physical activities regularly (OR, 2.05; 95% IC, 1.33 - 3.17). Minor mental disorders prevalence found was high, reaching more than 70% in some courses (e.g 77.8% among Biomedicine students), mainly associated with gender, sexual orientation and emotional support. Our study draws attention to the urgency of monitoring the mental health status of undergraduate students, and implementing mental health centers at universities, as well as facilitating access and improve existing centers. Key messages The high prevalence of minor mental disorders found among undergraduate students indicates the urgent need for interventions in this populations. Women and LGBT+ students are groups at higher risk for the development of minor mental disorders at university. Strategies must be created to reduce the higher prevalence in this populations.

Bullying is a behavior highly prevalent in schools worldwide and is associated with several mental disorders later in life. Considering its prevalence and impact in mental health, it is being recognized as a public health problem. We aimed to identify patterns of bullying victimization and perpetration in children and adolescence, and investigated its association with school performance, alcohol use and sociodemographic factors. A latent class analysis was conducted using baseline data collected from a randomized controlled trial conducted to evaluate the effectiveness of the drug prevention program PROERD (the Brazilian adaptation of the the US program 'Keepin it REAL”) carried out among 1.742 students in 5th grade and 2.316 in 7th grade, from 30 public schools of São Paulo city, Brazil. Two models of four latent classes each were identified among the students, in 5th and 7th grade: Low bullying, Moderate bullying victimization, High bullying victimization and High bullying victimization and perpetration. In both grades, we found that alcohol use were associated to all bullying latent classes (e.g High bullying victimization and perpetration (aOR=5,63; 95%CI = [3,05; 10,38] and aOR=3,29; 95%CI = [1,28; 8,43], 5th and 7th grade respectively). In 5th grade, girls were more likely to belong to the “High bullying victimization” class and to “Moderate bullying victimization” (aOR=1,75; 95%CI = [1,02; 3,01] and aOR=1,47; 95%CI = [1,16; 1,87], respectively); students who reported to belonging to black or brown races were more likely to belong to 'High bullying victimization' class (aOR=3,35; 95%CI = [1,34; 8,37]); low and medium school grades were associated to High bullying victimization and perpetration (aOR=10,12; 95%CI = [4,19; 24,41]) and Moderate bullying victimization (aOR=1,63; 95%CI = [1,17; 2,27]). The results show the need to implement school prevention programs that simultaneously address alcohol use and bullying components, besides taking into account race and gender norms. Key messages Bullying profiles help us to understand how this type of violence happens among students. And the associated factors indicate which groups are at greatest risk and need more attention. The use of alcohol associated with all latent classes, besides showing the impacts of bullying, it also indicates the importance of bullying prevention programs to address substance use prevention.