Experimentos históricos nos livros didáticos: implicações para o ensino de química

A história da ciência tem sido usada como importante contribuinte das relações de ensino, embasando uma melhor compreensão da atividade científica. Em muitos casos, porém, a descrição equivocada de episódios históricos pode dificultar o entendimento de conceitos e induzir visões distorcidas do que é a ciência e de como ela é feita. Neste trabalho, compilamos uma lista com 24 experimentos históricos encontrados em livros didáticos (LD) de Química voltados ao Ensino Médio e, a partir da análise de originais e da literatura secundária já produzida por historiadores da ciência, explicitamos diferenças entre as descrições de experimentos presentes nos LD e seus respectivos originais históricos. Os casos analisados envolvem a pilha de Daniell e o experimento com a folha de ouro de Rutherford. Comparando as descrições dadas pelos LD com os originais históricos, verificamos diferenças expressivas, tanto em relação às montagens e aos materiais utilizados pelos cientistas quanto na execução dos experimentos e em sua vinculação com proposições teóricas. No caso de Daniell, a separação da pilha em duas semicélulas conectadas por uma ponte salina representa uma distorção do original histórico que o afasta, também, das representações cotidianas de pilhas elétricas e de qualquer aplicação prática do dispositivo. Já no caso da folha de ouro, identificamos que as ilustrações tradicionais deste experimento representam um híbrido de ao menos quatro montagens realizadas pelo grupo de pesquisa de Rutherford. Também notamos que os LD tratam da proposição do modelo atômico como decorrência deste experimento, o que gera uma distorção da cronologia histórica com viés indutivista, uma vez que o modelo teórico de Rutherford foi proposto antes e alguns desses experimentos foram projetados, justamente, como tentativas de verificação do modelo. Apresentamos pontos em que essas distorções podem prejudicar o entendimento dos alunos e de que forma a fidelidade histórica pode ajudar o trabalho de professores em sala de aula

Understanding Depressive Symptoms after Bariatric Surgery: the Role of Weight, Eating and Body Image

Introduction: Depressive symptoms have been reported as prevalent after bariatric surgery. This study aims to analyze the role of weight, eating behaviors and body image in depressive symptomatology in bariatric surgery patients assessed post-operatively.Material and Methods: This is a cross-sectional study including 52 bariatric surgery patients assessed post-operatively with a follow-up time ranging from 22 to 132 months. Psychological assessment included a clinical interview (Eating Disorder Examination) to assess eating disorders psychopathology, and three self-report measures: Outcome Questionnaire 45 - general distress; Beck Depression Inventory - depressive symptoms; and Body Shape Questionnaire - body image.Results: Our data show that depressive symptoms after surgery are associated with loss of control over eating, increased concerns with body image, and body mass index regain. Multiple linear regressions was tested including these variables and showed that body mass index regain after surgery, loss of control over eating and concerns with body image significantly explained 50% of the variance of post-operative depressive symptoms, being the concern with body image the most significant variable: greater dissatisfaction with body image was associated with more depressive symptoms.Discussion: The results of this study showed that a subgroup of patients presents a significant weight gain after bariatric surgery, which is associated with episodes of loss of control over eating, concerns with body image and depressive symptoms.Conclusion: These results stress the relevance of body image concerns after surgery and the importance of clinically addressing these issues to optimize psychological functioning after bariatric surgery.Introdução: A sintomatologia depressiva tem-se revelado prevalente após a cirurgia bariátrica. Este estudo teve como objetivo com- preender o papel do peso, alimentação e imagem corporal na sintomatologia depressiva após realização da cirurgia bariátrica. Material e Métodos: Segue um design transversal e possui uma amostra pós-cirúrgica de 52 indivíduos, com um tempo de follow-up entre os 22 e os 132 meses. A avaliação foi realizada através de duas entrevistas clínicas semiestruturadas, incluindo a perturbação de comportamento alimentar (Eating Disorder Examination), e de três instrumentos de autorrelato: Outcome Questionnaire 45 - compro- metimento psicológico geral, Beck Depression Inventory - sintomatologia depressiva e Body Shape Questionnaire - imagem corporal. Resultados: Os resultados mostram que a sintomatologia depressiva está associada à ingestão alimentar compulsiva, à preocupação com a imagem corporal e à percentagem do índice de massa corporal ganho. Segundo os resultados da análise de regressão linear múltipla que incluiu estas variáveis, a percentagem de índice de massa corporal ganho após cirurgia, a ingestão alimentar compulsiva e a preocupação com a imagem corporal são os factores que explicam 50% da variância da sintomatologia depressiva após a cirurgia, sendo a preocupação com a imagem corporal mais significativo, na medida em que uma maior insatisfação com a imagem corporal está associada a mais sintomas depressivos. Discussão: Os resultados deste estudo mostraram que um subgrupo de doentes apresenta um aumento de peso significativo após a cirurgia bariátrica que está associado a episódios de ingestão alimentar compulsiva, a preocupações com a imagem corporal e a sintomatologia depressiva. Conclusão: Estes resultados enfatizam a importância de considerar estas preocupações com a imagem corporal na avaliação psi- cológica da pessoa que fez cirurgia bariátrica de modo a otimizar o seu funcionamento psíquico e adesão ao tratamentoFundação para a Ciência e Tecnologia, Portugal através do projeto (PTDC/MHC-PCL/4974/2012) e bolsa (SFRH/ BPD/78896/2011) concedidos a Eva Conceição, e do pro- jeto (PTDC/PSI-PCL/099981/2008) concedido a Paulo Ma- chadoinfo:eu-repo/semantics/publishedVersio

Cross-cultural adaptation and measurement properties of the Portuguese version of the Ankle Instability Instrument

Chronic ankle instability is one of the most common clinical conditions in the general population, especially in adult athletes. The cross-cultural adaptation of self-reported questionnaires that identify and classify this condition contribute to criteria standardization in research but also in rehabilitation. Aim of Study. To validate the Ankle Instability Instrument to the Portuguese population and to investigate its psychometric properties. Material and Methods. Linguistic and semantic equivalence of the original version of the Ankle Instability Instrument to the Portuguese population was firstly performed. The Portuguese version of the Ankle Instability Instrument was then applied to 81 higher education adult students, with (n = 59) and without history of ankle sprain (n = 22). Participants were evaluated two times with an interval of one week to assess the psychometric properties of the Portuguese version of the Ankle Instability Instrument. Results. In the reliability of binary responses based on the test retest, the tetrachoric correlation coefficient ranged from 0.99 to 1.00. In addition, the Kuder–Richardson coefficient was 0.79 suggesting good internal consistency. Conclusions. Test-retest showed an almost perfect match in all answers between the two moments, which seem to be related to sample characteristics. The internal consistency value was similar to the one obtained in the original version. The Portuguese version of the Ankle Instability Instrument is highly reliable and can be used in clinical practice.info:eu-repo/semantics/publishedVersio

Uma nova matéria-prima na produção de biodiesel: sementes do pinhão-roxo

Biodiesel is an alternative fuel that is produced through oil plants or animal fat. It is a renewable energy source, with biodegradable characteristics, to emit less pollutant than diesel. Thus, this work aims to show the production of biodiesel from the purple-pinion (Jatropha gossypiifolia L.) seeds. In addition to the synthesis, the physical-chemical characterization of both the raw material and the final product was carried out. The biodiesel synthetic route was performed by the basic catalytic transesterification reaction, using potassium hydroxide (KOH) in the presence of methanol (CH3OH) in the molar ratio of 1: 3 (oil: methanol). As a result, it was observed that the mass conversion of the biodiesel was 22.05 g. The physical-chemical analyzes carried out were acid index of 0.106 mgKOH / g, according to ANP technical resolution. The peroxide index of 1.03 meqO2 / kg, the kinematic viscosity of 20 ° C to 40 ° C, obtained was 6.455 mm2/s and 3.5343 mm2/s, the values are close to the ANP technique resolutions. Stability was 0.26 hours, and the biodiesel burning test was executed for approximately 3 hours. Therefore, there is a high viability of biodiesel production through the purple pinion seeds.O biodiesel é uma alternativa de combustível que é produzido através das plantas oleaginosas ou gordura animal. É fonte de energia renovável, com características biodegradáveis, por emitir menos poluentes que o diesel. Assim, este trabalho tem como objetivo mostrar a produção de biodiesel a partir das sementes pinhão-roxo (Jatropha gossypiifolia L.). Além da síntese, foi realizado a caracterização físico-química, tanto da matéria prima, como o produto final. A rota sintética do biodiesel foi realizada pela reação de transesterificação via catalise básica, utilizando o hidróxido de potássio (KOH) na presença de metanol (CH3OH) na razão molar de 1:3 (óleo: metanol). Como resultado, observou-seque a conversão em massa do biodiesel foi 22,05 g. As análises físico-químicas realizadas foram: índice acidez de 0,106 mgKOH/g, estão de acordo com resolução técnica da ANP. O índice peróxido de 1,03 meqO2/Kg, a viscosidade cinemática de 20°C a 40°C, obtida foi de 6,455 mm2/s e 3,5343 mm2/s, os valores estão próximos das resoluções de técnica da ANP, a estabilidade oxidativa foi 0,26 horas, e o teste de queima do biodiesel durou aproximadamente 3 horas. Portanto, existe uma alta viabilidade de produção do biodiesel através das sementes de pião roxo

Recomendações para avaliação de populações de minhocas em ecossistemas brasileiros

Earthworms are often related to fertile soils and are also frequently used as environmental quality indicators. However, to optimize their use as bioindicators, earthworm populations must be evaluated together with the environmental and anthropogenic variables regulating their communities. This review sought to identify the earthworm-sampling, soil chemical and physical, and environmental and anthropogenic attributes evaluated in 124 published studies that quantified earthworm abundance (>7,300 samples) in 765 sites with different types of climate, soils, land use, and management systems in Brazil. Soil chemical and physical attributes (except pH) were less reported (≤50% of studies) than other environmental variables such as sampling date, altitude, temperature, precipitation, climate and soil type, and land use (>50% of studies). Earthworms were rarely identified (24%) and few studies (31%) measured their biomass, although most provided adequate information on sampling protocol. Based on their importance in regulating earthworm populations, a set of variables is proposed to be evaluated when studying earthworm communities and other macrofauna groups. This should help guide future studies on earthworms in Brazil and other countries, optimize data collection and replicability, allow comparisons between different studies, and promote the use of earthworms as soil quality bioindicators.As minhocas são frequentemente relacionadas a solos férteis e, também, bastante usadas como indicadores da qualidade ambiental. No entanto, para otimizar seu uso como bioindicadores, as populações de minhocas devem ser avaliadas juntamente com as variáveis ambientais e antropogênicas que regulam as suas comunidades. Esta revisão buscou identificar os atributos relacionados à amostragem de minhocas, físicos e químicos dos solos, e ambientais e antropogênicos avaliados em 124 estudos publicados que quantificaram a abundância de minhocas (>7.300 amostras) em 765 locais com diferentes tipos de clima, solos, uso da terra e sistemas de manejo no Brasil. Os atributos químicos e físicos do solo (exceto pH) foram menos relatados (≤50% dos estudos) do que outras variáveis ambientais, como data de coleta, altitude, temperatura, precipitação, tipo de solo e de clima, e uso do solo (>50% dos estudos). As minhocas foram raramente identificadas (24%) e poucos estudos (31%) mediram sua biomassa, embora a maioria tenha fornecido informações adequadas sobre o protocolo de amostragem. Com base na sua importância para a regulação das populações de minhocas, propõe-se um conjunto de variáveis que devem ser avaliadas no estudo de comunidades de minhocas e outros grupos da macrofauna do solo. Isso deve ajudar a guiar futuros estudos sobre minhocas no Brasil e em outros países, otimizar a coleta e a replicabilidade de dados, permitir comparações entre diferentes estudos e promover o uso de minhocas como bioindicadores da qualidade do solo

Organic functions: ludicity as a learning facilitation tool

The learning process can be more engaging and relaxed when instructional resources promoting these qualities, such as instructional games, are employed. Ludicity, i.e., the quality of being playful and enjoyable, can be much more than mere play; it can assist in the teaching and learning of the curriculum content. When alternative teaching methods are adopted, outcomes can exceed mere learning. They can also motivate students to participate actively in the teaching-learning process. In this context, the game “Unraveling Organic Functions” was conceived with the aim of facilitating student learning and retaining of organic functions and nomenclature of organic compounds by promoting student engagement. Based on traditional follow-the-path board games, “Unraveling Organic Functions” was employed as an instructional activity at a public school in Itacoatiara (AM), Brazil, as part of an intervention-research project of a qualitative nature. Data were collected by means of questionnaires responded by the participating students and teacher and pre- and post-intervention tests responded by the former. The results indicate that the participants found the experience engaging and enjoyable. They also suggest that the game in question facilitated learning and retaining of the aforementioned concepts and theories, thus corroborating the importance of including ludic classroom activities in the teaching-learning process.The learning process can be more engaging and relaxed when instructional resources promoting these qualities, such as instructional games, are employed. Ludicity, i.e., the quality of being playful and enjoyable, can be much more than mere play; it can assist in the teaching and learning of the curriculum content. When alternative teaching methods are adopted, outcomes can exceed mere learning. They can also motivate students to participate actively in the teaching-learning process. In this context, the game “Unraveling Organic Functions” was conceived with the aim of facilitating student learning and retaining of organic functions and nomenclature of organic compounds by promoting student engagement. Based on traditional follow-the-path board games, “Unraveling Organic Functions” was employed as an instructional activity at a public school in Itacoatiara (AM), Brazil, as part of an intervention-research project of a qualitative nature. Data were collected by means of questionnaires responded by the participating students and teacher and pre- and post-intervention tests responded by the former. The results indicate that the participants found the experience engaging and enjoyable. They also suggest that the game in question facilitated learning and retaining of the aforementioned concepts and theories, thus corroborating the importance of including ludic classroom activities in the teaching-learning process

Using forensics to teach the natural sciences and raise student consciousness about gender-based social issues

The way the Natural Sciences has been conventionally taught in school, i.e., by means of lecture-based methods, has been shown ineffective. For this reason, many alternative methods of teaching and learning have been proposed. This study focuses on the teaching of the Natural Sciences by the employ of ludic investigative activities in the context of forensic science. It proposes an alternative way of teaching the Natural Sciences associated with issues relevant to students and society at large. To this end, a case of femicide was used to teach topics of the Natural Sciences while addressing an important social issue, i.e., gender-based violence. This research, a case study of a qualitative nature, was carried out at Colégio de Aplicação in Macaé (CAp), RJ, Brazil. Its proposed teaching-learning activities were conducted over three consecutive 90-minute classes. The participating students answered pre- and post-intervention questionnaires on the scientific concepts addressed by the activities and the social issue in question, i.e., femicide. The students also participated in a discussion about the social issue at hand at the end of the intervention. The analysis of the collected data suggests that the teaching-learning method employed in this research is a viable way of teaching the Natural Sciences, especially Chemistry, in an interdisciplinary and contextualized fashion