O papel da experienciação no ensino de eletroquímica: contexto e reflexões sobre a prática docente de uma licencianda em química.

O presente trabalho propõe uma reflexão crítica sobre experienciação discente por meio da prática docente de uma licencianda em química. A motivação surgiu a partir da busca por materiais didáticos capazes de facilitar o aprendizado de alunos do ensino médio no que tangencia conceitos de eletroquímica, sua contextualização e transversalidade. Para tal, investigou-se alguns experimentos sobre pilhas - dentre as quais: (i) pilha de compartimento único, (ii) pilha de Daniell, (iii) derivações com pilha de concentração e pilha de temperatura – e corrosão. A lente adotada foi colimada pelos resultados de 2015 do Programa Internacional de Avaliação de Estudantes (PISA, 2015), utilizados pelo governo brasileiro como um dos indicadores, tanto do nível de letramento científico da população em processo de escolarização, quanto das supostas causas que corroboram para o cenário por ele apresentado. O projeto propõe algumas ferramentas didáticas – como aulas experimentais, vídeos e mapas conceituais - capazes de enriquecer a aprendizagem discente. As ferramentas adotadas dialogaram com referenciais teóricos epistemológicos previamente escolhidos, dentre os quais: Bachelard, Dewey, Perrenoud, Ausubel, Bloom e Vygotsky. Em suma, trata-se de uma pesquisa de natureza qualitativa, com delineamento bibliográfico-experimental, que, a partir de uma temática específica, no caso pilhas, traça um perfil histórico, e apresenta ideias centrais do que concerne aprendizado eficiente e estratégias de ensino, a partir de aulas teórico-experimentais. No processo avaliativo dos alunos foram desenvolvidos experimentos de células galvânicas, sendo as células de Daniell, temperatura, concentração e compartimento único, consistindo em analisar as dificuldades observadas no desenvolvimento dos roteiros das práticas, correlacionando os conteúdos com assuntos que fazem parte da vivência dos sujeitos e também questões interdisciplinares que podem ser abordadas para além do assunto central, contemplando uma transversalização de conteúdo. A ix análise proposta destaca a importância da experimentação - contextualizada e crítica - no processo de empoderamento de competências e habilidades, não somente aquelas as quais os Parâmetros Curriculares Nacionais orientam os professores a trabalhar com seus alunos, mas principalmente às almejadas individualmente e coletivamente pelos discentes

Desafios do ensino remoto emergencial de biologia na concepção de professores do ensino médio que são ou foram vinculados ao Programa de Mestrado Profissional em Ensino de Biologia - PROFBIO - UnB

Trabalho de Conclusão de Curso (graduação) — Universidade de Brasília, Instituto de Ciências Biológicas, Núcleo de Educação Científica - NECBio, 2021.O mundo tem vivenciado um cenário pandêmico avassalador, cujos desdobramentos levaram à modificações dramáticas em diferentes contextos, individuais e/ou coletivos, das nossas vidas. O contexto Educacional envolve muitos atores e, portanto, muitos são os afetados. Dessa forma, foram implementadas alterações emergenciais com o intuito de dar continuidade ao processo de ensino-aprendizagem, tentando, assim, preencher a lacuna aberta pela falta da Escola. O ensino passou, abruptamente, do modo presencial para a forma remota. Pensando nas questões envolvidas nesse processo, o objetivo do presente estudo foi buscar identificar as principais dificuldades enfrentadas para ensinar no modo remoto emergencial, na concepção de professores de biologia do Ensino Médio da rede pública. Foi utilizado um método qualitativo, sendo aplicado um questionário por meio da plataforma Google Forms, com questões objetivas e subjetivas. O público-alvo foi constituído por docentes de biologia que foram ou são vinculados ao Programa de Mestrado Profissional em Ensino de Biologia (PROFBIO) da Universidade de Brasília, visto que estes, obrigatoriamente, são professores da rede pública no exercício da função. Responderam ao questionário 32 professores, sendo a grande maioria mulheres (65,6%). Quando questionados sobre experiência prévia para lecionar de forma remota, 68,8% responderam que não têm formação ou experiência. Entretanto, 100% dos respondentes estão dando aula remota através de um ou mais meio de transmissão virtual como WhatsApp (78,1%), Google Classroom (71,9%), Youtube (46,9%), Google Drive (43,8%), Zoom Meeting (37,5%), E-mail da turma (18,8%); Redes Sociais (Facebook e Instagram) (15,6%), Microsoft Teams, Moodle e Kahoot (12,5%) ou Google Meet (6,3%). No tocante às dificuldades vivenciadas com o ensino remoto, as respostas foram: sobrecarga de trabalho (81,3%), conexão de internet lenta e/ou instável (37,5%), dúvidas sobre as abordagens metodológicas para ensinar biologia online (34,4%), ambiente doméstico inapropriado para home office, questões ligadas à saúde mental, insegurança quanto à gravação e uso não autorizado de imagem e voz (28,1%), dificuldades no domínio das TDIC’s (18,8%). De forma geral, as respostas dos participantes indicaram que são muitos os desafios enfrentados por esses profissionais da educação, principalmente o fato de não se sentirem preparados para atuar no modo remoto, tendo em vista que a grande maioria não tem formação e/ou qualificação para tal. Esses resultados estão em consonância com a maioria daqueles obtidos em outros estudos sobre esse tema.The world has been experiencing an overwhelming pandemic scenario, whose consequences have led to dramatic changes in different contexts, individual and/or collective, of our lives. The Educational context involves many actors and, therefore, many are affected. Thus, emergency changes were implemented in order to continue the teaching-learning process, thus trying to fill the gap opened by the lack of the School. Teaching abruptly changed from face- to-face to remote. Thinking about the issues involved in this process, the aim of this study was to identify the main difficulties faced to teach in emergency remote mode, in the conception of high school biology teachers in the public network. A qualitative method was used, with a questionnaire being applied through the Google Forms platform, with objective and subjective questions. The target audience was made up of biology professors linked to the Professional Master's Degree Program in Biology Teaching (PROFBIO) at the University of Brasília, as these are, necessarily, public school teachers in the exercise of their function. 32 teachers answered the questionnaire, the vast majority of them women (65.6%). When asked about previous experience to teach remotely, 68.8% responded that they have no training or experience. However, 100% of respondents are teaching remotely through one or more virtual transmission media such as WhatsApp (78.1%), Google Classroom (71.9%), Youtube (46.9%), Google Drive (43, 8%), Zoom Meeting (37.5%), Class email (18.8%); Social Networks (Facebook and Instagram) (15.6%), Microsoft Teams, Moodle and Kahoot (12.5%) or Google Meet (6.3%). Regarding the difficulties experienced with remote teaching, the answers were: work overload (81.3%), slow and/or unstable internet connection (37.5%), doubts about the methodological approaches to teaching biology online (34 .4%), home environment inappropriate for the home office, issues related to mental health, insecurity regarding recording and unauthorized use of image and voice (28.1%), difficulties in mastering TDICs (18.8%). In general, the responses of the participants indicated that there are many challenges faced by these education professionals, especially the fact that they do not feel prepared to work remotely, considering that the vast majority do not have training and/or qualification to such. These results are in line with most of those obtained in other studies on this topic

A JORNADA DO “HERÓI” EM O HOBBIT: BILBO BOLSEIRO E O MONOMITO

O trabalho aqui apresentado analisa o livro O Hobbit, de J. R. R. Tolkien, baseando-se na concepção da jornada do herói, sendo o personagem principal do livro, Bilbo Bolseiro, discutido sob essa perspectiva. Utilizando dois autores principais como arcabouço teórico para a análise, Joseph Campbell (1997) e Margery Hourihan (1997), verificamos se e de que modo Bilbo Bolseiro, um personagem que não apresenta características extraordinárias, pode ser considerado o herói da referida narrativa

History-indicated transvaginal cerclage: results from a single-centre

Background: Cervical incompetence occasionally results in mid-trimester pregnancy loss, preterm labour and increased foetal morbimortality. History-indicated cerclage is proposed when obstetric history suggests cervical incompetence. The aim of this study was to evaluate the maternal-foetal outcomes following prophylactic cervical cerclage.Methods: Retrospective study reviewing data of all women undergoing transvaginal history-indicated cerclage from January 1st, 2008 to December 31th, 2017 at Centro Hospitalar Universitário do Algarve - Faro. Primary outcome: gestational age <37weeks at birth. Secondary outcomes: neonatal morbimortality and intensive care unit (NICU) admission and maternal morbidity. Data were analyzed with IBM SPSS Statistics 23.Results: A total of 12 history-indicated cerclages were performed (9 women). At first cerclage, mean maternal age, gestity, parity and live children were 27.6, 2.44, 1.11 and 0.78 (87.7% preterm), respectively. At cerclage placement, mean gestational age and cervical length were 16.1 weeks and 27.5mm. Average hospital admission was 10.7 days. In all cases McDonald technique was performed. Four hospital readmissions occurred for threatened labour. Mean gestational age at cerclage removal was 36.9 weeks (83.3% in ambulatory) and 38.9 at delivery. Average time between cerclage removal and labour was 14.5 days. Spontaneous onset of labour occurred in 75% and vaginal delivery in 83.4%. There were no reports of preterm birth, foetal admission to NICU or maternal complications. Mean number of live children after procedure was 1.58.Conclusions: Prophylactic cervical cerclage seems to improve pregnancy outcome with minimal maternal risks. However, our data suggest over inclusion of women, with unnecessary procedures, emphasizing the importance of re-evaluating inclusion criteria

Preliminary validation system for cuffless blood pressure measurement

The development of a non-invasive, cuffless, continuous, wearable device for the measurement of blood pressure is a complex endeavour due to the high specificity at each measuring site and the need for high accuracy. Proof-of-concept and validation of a prototype should be performed at an early stage for functionality assessment. Additionally, the emergence of biological computer models allows for in-silico research, which results should be verified in a practical experiment. To grant an optimal preliminary assessment of a prototype, this work aimed to develop and validate accurate in-vitro and ex-vivo arterial models, with simple construction and easily available components. The comparison between a silicone tube and a porcine artery as a mimicked human radial artery was based on the stiffness parameter. Flow pressure is controlled by a centrifugal heart-like pump. Pressure values are extracted with ultrasound and a commercial piezoresistive pressure sensor is used for pressure validation. The porcine artery showed much more realistic stiffness values (·=15.360) than the silicon tube (·=543.420), which was very stiff in comparison to the typical in-vivo radial artery stiffness (·=9.5). The decrease in stiffness of 97.173 % (from the silicone tube to the porcine artery) led to an acute decrease in the derived pressure error. This work serves as guidelines for the development of a low-budget arm phantom, as the simple setup allowed for a primary validation of a proof-of-concept ultrasound-based sensor for the measurement of pressure.(undefined

Formation and evaluation of chitosan nanoparticles with antibacterial and emulsifying properties for food application

info:eu-repo/semantics/publishedVersio

Novos requisitos técnicos para rotulagem nutricional nos alimentos embalados: overview de revisões

Introduction: Personal food preferences, purchasing decisions and eating behaviors are shaped by price, marketing, availability and accessibility, which are influenced by health policies and regulations. The National Health Surveillance Agency in Brazil (Anvisa) published in 2009 a public consultation on the proposal for a Normative Instruction that establishes the technical requirements for declaring nutrition labeling in packaged foods. However, the path through which a legislative proposal is implemented is permeated by several possibilities, being subject to disputes by interest groups, such as consumers and food companies. Objective: to carry out a comparison between the new technical requirements for declaring nutrition labeling in packaged foods with the literature on the standardization of food labels and the effects on the influence on the population’s food choices. Method: An overview of systematic reviews was conducted to carry out a comparative study between the scientific evidence and the new technical requirements for declaring nutrition labeling proposed by Anvisa. Results: Of the 99 studies identified, six systematic reviews, published from 2011 to  2018, were included. The reviews reported positive results in the presentation of nutritional information on food labels, especially when dealing with healthy choices by consumers. Based on this outcome, Anvisa’s regulation follows international labeling standards so that consumers can have more information, which favors the promotion of healthy food choices. Conclusions: The Public Consultation on nutritional labeling of foods is based on the interventions studied and on the current evidence, which ensures reliability for decision-making by the Ministry of Health and Anvisa.   Introdução: As preferências alimentares pessoais, as decisões de compra e os  comportamentos alimentares são moldados pelo preço, marketing, disponibilidade e acessibilidade, os quais são influenciados por políticas e regulamentações sanitárias. A Agência Nacional de Vigilância Sanitária (Anvisa) publicou em 2009 uma consulta pública da  proposta de Instrução Normativa que estabelece os requisitos técnicos para declaração da rotulagem nutricional nos alimentos embalados. No entanto, o percurso pelo qual uma proposta de legislação passa a ser implementada é permeado por diversas possibilidades, estando sujeita a disputas por parte de grupos de interesse, como consumidores e empresas alimentícias. Objetivo: Realizar uma comparação entre os novos requisitos técnicos para declaração da rotulagem nutricional nos alimentos embalados com a literatura sobre a padronização de rotulagens de alimentos e os efeitos sobre a influência nas escolhas  alimentares da população. Método: Foi conduzida um overview de revisões sistemáticas para realização de um estudo comparativo entre as evidências científicas e os novos requisitos técnicos para declaração da rotulagem nutricional propostos pela Anvisa. Resultados: Dos 99 estudos identificados, foram incluídas seis revisões sistemáticas, publicadas de 2011 a 2018. As revisões reportaram resultados positivos na apresentação de informações nutricionais nos rótulos dos alimentos, principalmente se tratando de escolhas saudáveis por parte dos consumidores. Baseados nesse desfecho, a regulação da Anvisa segue os padrões de rotulagem internacionais para que assim os consumidores  possam ter mais informações, o que favorece a promoção de escolhas alimentares saudáveis. Conclusões: As consultas públicas sobre rotulagem nutricional de alimentos estão fundamentadas nas intervenções estudadas e nas evidências atuais, o que assegura confiabilidade para a tomada de decisão do Ministério da Saúde e da Anvisa

Surface degradation of composite resins by acidic medicines and ph-cycling

This study evaluated the effects of acidic medicines (Dimetapp® and Claritin®), under pH-cycling conditions, on the surface degradation of four composite resins (microhybrid: TPH, Concept, Opallis and Nanofilled: Supreme). Thirty disc-shaped specimens (Ø = 5.0 mm / thickness = 2.0 mm) of each composite were randomly assigned to 3 groups (n = 10): a control and two experimental groups, according to the acidic medicines evaluated. The specimens were finished and polished with aluminum oxide discs, and the surface roughness was measured by using a profilometer. After the specimens were submitted to a pH-cycling regimen and immersion in acidic medicines for 12 days, the surface roughness was measured again. Two specimens for each material and group were analyzed by scanning electron microscopy (SEM) before and after pH-cycling. Data were analyzed by the Student's-t test, ANOVA, Duncan's multiple range test and paired t-test (&#945;=0.05). Significant increase in roughness was found only for TPH in the control group and TPH and Supreme immersed in Claritin® (

Effect of fluoride, chlorhexidine or Nd:YAG on the progression of root dentin demineralization after removal of the demineralized organic matrix

Quantification of collagen degradation is an important parameter to evaluate dentin caries for preventive aid.&nbsp;Objectives: Evaluate preventive methods against root collagen degradation by the hydroxyproline assay (HYP) and microradiography technique (MRT). Methodology: Five bovine root dentin blocks were obtained and subjected to an artificial demineralization process by acetate buffer (pH 5) to induce carious lesion formation. Samples were subjected to the following therapeutic treatments: 1) 0.12% chlorhexidine for 1 min, 2) 2% fluoride for 1 min, 3) Nd:YAG Laser (400 μm diameter optical fiber, 10 Hz frequency, 60 mJ/pulse energy, 48 J/cm2 energy density, in noncontact mode for 10 s), 4) deionized water (control) for 1 min, 5) MRT control group (without treatment and removal of collagen). Samples were exposed to degradation by a collagenase enzyme for five days. The enzyme solution was collected, by colorimetry in a spectrophotometer, from the collagen matrix for the hydroxyproline release analysis. The same samples were subjected to an additional two days of demineralization to induce the progression of mineral loss. Samples were analyzed by MRT for the visualization of their degraded areas (estimation of lesion depth and mineral loss). ANOVA was applied to compare hydroxyproline release rates. MRT data were subjected to the Kruskal-Wallis test, followed by the Dunn’s test. Comparisons between the initial five-day and the subsequent two-day demineralization processes were performed by repeated t-test or Wilcoxon (p&lt;0.05) measurements. Results: The amount of HYP released from the dentin samples failed to show significant differences among the groups (p=0.09). Fluoride and chlorhexidine were able to interact with the samples, reducing the progression of dentin caries after removal of the demineralized organic matrix. CHX was the only treatment able to show significant lower lesion depth than the negative control. Conclusion: Chlorhexidine and fluoride were effective in reducing root caries progression