433 research outputs found
Pre-service Teachers\u27 Knowledge: Analysis of teachers\u27 education situation based on TPACK
This paper identifies the knowledge that emerges from collaborative situations, in an initial teachers’ education with integration of digital technology for teaching of function, in a blended and collaborative modality course, aiming to emerge Technological, Pedagogical and Content Knowledge (TPACK) in pre-service teachers. The method comprised the design of a teachers’ collaborative training experiment. The experiment had five phases, from a theoretical discussion to plan an Instrumental Orchestration to teach function with digital resources. Collaboratively, students worked in groups. The participants were students from a Mathematics teachers’ education. The experiment took place in the Teaching Methodology of Mathematics discipline at a public university in Brazil. This article focuses on the analysis of students’ knowledge in the planning stage, carried out collaboratively. The data analysis pointed out the three types of Technological, Pedagogical and Content knowledge were identified in different phases of the experiment, sometimes collectively, sometimes individually. In addition, we also identified that some intersections of TPACK emerged from the interactions; despite being in the initial stage of training, the students show pedagogical knowledge linked to knowledge of the content they had at the time of the training experiment
O fracasso escolar na Amazônia: uma abordagem sistêmica da atuação das organizações políticas na educação do Pará / School failure in the Amazon: a systemic approach to the performance of political organizations in Pará education
Este artigo descreve a organização do sistema político e educacional na modalidade de ensino médio público do estado do Pará. O objetivo foi apresentar o fenômeno do “fracasso escolar” e sua relação com as ações políticas das organizações de gestão (alta e média). Fez uma pesquisa qualitativa básica com uso de websurvey e entrevistas com gestores e como complemento análise documental. Os resultados indicam que a interferência exagerada do sistema político no sistema educacional é fator gerador do “fracasso escolar” como fenômeno social que afeta o sistema político e em seu entorno. Conclui que a atuação das organizações do campo político produz decisões para estabilizar o sistema educacional e promover o sucesso escolar, porém o resultado é o “fracasso”
Discussing different approaches for the time-zero as start for autogenous shrinkage in cement pastes containing superabsorbent polymers
Many studies have already been published concerning autogenous shrinkage in cementitious materials. Still, no consensus can be found in the literature regarding the determination of the time-zero to initiate the recording of autogenous shrinkage. With internal curing agents, a correct evaluation of their efficiency depends on an appropriate choice of the time-zero. This study investigates different approaches to estimate the time-zero for cement paste mixtures with and without superabsorbent polymers as internal curing agents. The initial and final setting times were determined by an electronic Vicat and ultrasonic pulse velocity measurements (UPV); the transition point between the fluid and solid state was determined from the autogenous strain curve; the development of the capillary pressure was also studied. The choice of time-zero before the transition point led to higher values of shrinkage strain that should not be taken into account for autogenous shrinkage. A negligible difference was found between the strains when the final setting time and the transition point were taken as time-zero. Considering the artefacts and practical issues involving the different methods, the use of the transition point from the autogenous strain curve is the most suitable technique for determining the time-zero
O LUGAR DE FALA NA NARRATIVA DE CONCEIÇÃO EVARISTO: NOTAS SOBRE A LITERATURA NEGRA NO BRASIL CONTEMPORÂNEO
Este estudo analisa traços da literatura periférica, buscando apresentar o lugar de fala na narrativa de Conceição Evaristo, como representações de ambientes periféricos e marginalizados. A partir dos estudos de Djamila Ribeiro (2017) e tendo como base os contos Maria e Olhos d’água (EVARISTO, 2016), a temática traz um questionamento sobre a importância da literatura negra/afro-brasileira para a descentralização do cânone brasileiro, que estabeleceu critérios do que seria arte literária embasados na exclusão e elitização. Como aporte teórico, utilizamos Borges (2019), com uma reflexão sobre a marginalização; Duarte (2013, 2020), revelando aspectos da literatura negra/afro-brasileira; Oliveira (2011), que acrescenta reflexões sobre os conceitos de “marginalidade” e “periferia”; e Rosa (2015), com os estudos de simbologias, para contribuir na análise dos textos. A intenção é problematizar e não esgotar as questões que envolvem o perfil da arte literária brasileira, procurando democratizar a ação do dizer, levando em consideração a pluralidade de culturas e lugares sociais e suas representatividades
18 Anos de Brasileirinho, de Maria Bethânia: uma pesquisa sobre as identidades brasileiras
Com o objetivo de analisar aspectos da diversidade cultural brasileira presentes na obra Brasileirinho (2003), da cantora Maria Bethânia, apresentamos a pesquisa, em diversos segmentos das artes (música, literatura, pintura), na tentativa de pintar um quadro significativo sobre as identidades brasileiras em seus contextos geo-históricos e socioculturais. A escolha da obra se deu pela necessidade de apresentar um exemplar artístico atual sobre a temática e enfatizar elementos da brasilidade no âmbito dos estudos culturais contemporâneos, como o hibridismo, a decolonialidade e interculturalidade. Utilizando a Revisão Bibliográfica, baseamos as análises em Canclini (2010), Hall (2015), Andrade (1928; 1933) e Veloso (2008; 2012). As conclusões desvendam a importância de estudos socioculturais na obra da cantora, ao valorizar, em sua trajetória artística, expressões marginalizadas, como as religiões de matriz africana, as divindades dos povos indígenas, o papel dos imigrantes e as artes afrobrasileiras na formação sociocultural do povo brasileiro
The Man Creates Instruments that Transform Himself: An Overview of GERE Research within Mathematics Education
This paper discusses GERE (Study Group on Resources for Education) members’ research trajectory in three different lines: Teaching practice and practice management, Teacher education and identity, and Support for learning and resource generation. It discusses how researchers seek to understand technology integration in the practice of distance education in Brazil, with the instrumental orchestrations lens, revealing the changes made in the didactic configurations, from the multiplicity of teachers responsible for each discipline. Teachers’ documentation is discussed in the process of resource elaboration and use and guided by design, experimentation, and reflection of the generated instrument, such as digital textbooks and mathematical games. The notion of integrating artefacts is discussed both from the perspective of collaborative learning and of instrumental meta-orchestration, a teacher education model about instrumental orchestration. Finally, thinking about the artefact as a support for learning also made us work on generating devices aimed at specific concepts such as covariation in learning functions
Exploring different choices of 'time zero' in the autogenous shrinkage deformation of cement pastes containing superabsorbent polymers
Shrinkage in concrete structures has been the focus of many studies. Lately a lot of attention has been given to autogenous shrinkage. Although it may not be prominent in ordinary concrete structures, in systems with very low water-to-cement/binder ratio (ultra-high performance concrete for example) it can become a serious issue associated with the cracking of the structure at early age. This type of shrinkage develops due to a reduction in the internal relative humidity of the material and it is also associated to the development of capillary pressure in the pore system due to receding menisci. A big challenge in studying autogenous shrinkage is determining the "time-zero". Given a lack of consensus in literature, this study aimed to investigate the influence of different estimations of time-zero: the final setting time determined by both an electronic Vicat apparatus and ultrasonic measurements; the "knee-point" in the shrinkage curve; and the capillary pressure build-up. Cement pastes with and without superabsorbent polymers (SAPs) were produced with Portland cement CEM III-B 42.5 N and superplasticizer (Glenium 51, 35% conc.). SAPs have proven to be quite effective in the mitigation of autogenous shrinkage as they can act as water reservoirs for the system. Among all methods, the capillary pressure was very suitable for all mixtures. For those containing SAPs no difference was found in picking the time-zero with any method. For the one without SAPs and lower w/c the choice of time-zero based on the setting time led to a different magnitude of autogenous shrinkage deformation in comparison to the other methods, which could be interpreted as an underestimation of the autogenous shrinkage deformation
Análise histológica da biocompatibilidade de três diferentes cimentos obturadores a base de hidróxido de cálcio
OBJECTIVE: To histologically evaluate the behavior of the subcutaneous tissue of rats after placement of polyethylene tubes filled with calcium hydroxide-based root canal sealers (SealapexTM, ApexitTM e Sealer 26TM). STUDY DESIGN: The study employed 60 rats, which were divided into eight groups, being four experimental groups with 10 rats each, and four control groups with five rats. Analysis was conducted at 48 hours, 7, 21 and 60 days. RESULTS: Histological analysis revealed that all sealers were irritant; however, the intensity varied between each sealer and as a function of time. At the initial periods (48 hours and seven days), all materials demonstrated similar outcomes, with inflammatory reaction from severe to moderate, respectively. At the final periods (21 and 60 days), the tissue reactions to the implants containing SealapexTM displayed an active status yet with regression, compared to the ApexitTM and Sealer 26TM. The control groups exhibited less inflammatory cells than the experimental groups, keeping a reaction status with regression. CONCLUSIONS: The results achieved in this study revealed that the SealapexTM sealer was the most compatible, followed by ApexitTM and Sealer 26TM.INTRODUÇÃO: O tratamento endodôntico tem seus procedimentos clínicos fundamentados em conhecimentos básicos, principalmente biológicos, cujo êxito do tratamento depende das condições dos tecidos da região apical e periapical, dos mecanismos de defesa orgânicos e da potencialidade de reparação das células. Diferentes materiais obturadores, com os mais diferentes componentes químicos, têm sido testados em busca de uma substância que tenha propriedades físico-químicas e principalmente biológicas ideais para perfeita vedação do canal radicular. Um fato importante referente aos insucessos nos tratamentos endodônticos diz respeito aos componentes tóxicos dos cimentos obturadores de canal, incluídos com o propósito de neutralizar as falhas de desinfecção durante o preparo do canal. OBJETIVO: Avaliar histologicamente o comportamento tecidual subcutâneo de ratos após implantes de tubos de polietileno preenchidos com cimentos obturadores de canal à base de hidróxido de cálcio (Sealapexâ, Apexitâ e Sealer 26â). MATERIAL E MÉTODO: Foram utilizados para este estudo 60 ratos, os quais foram divididos em oito grupos: quatro grupos experimentais, cada um com 10 ratos, e quatro grupos controle, com cinco ratos. Foram analisados em intervalos de 48 horas, 7, 21 e 60 dias. RESULTADOS: Os resultados da análise histológica mostraram que todos os cimentos foram irritantes, porém em intensidade que variaram entre si e em função do tempo. Nos períodos iniciais (48 horas e sete dias) todos os materiais exibiram resultados próximos, com quadro inflamatório entre severo e moderado, respectivamente. Nos períodos finais (21 e 60 dias), as reações teciduais aos implantes contendo o cimento Sealapexâ apresentaram quadro ativo, mas em fase involutiva, em relação aos cimentos Apexitâ e Sealer 26â. Os grupos controle apresentaram número de células inflamatórias inferior aos grupos experimentais, mantendo quadro reacional em fase involutiva. O método estatístico utilizado foi a análise de variância para que fosse feita uma comparação entre as médias. CONCLUSÕES: Conclui-se que o cimento Sealapexâ foi o mais biocompatível seguido pelo Apexitâ e Sealer 26â
The herpetofauna of the Serra do Urubu mountain range: a key biodiversity area for conservation in the brazilian atlantic forest
The Serra do Urubu mountain range is considered a key biodiversity area. It is situated in the Pernambuco Endemism Center, one of the most threatened regions of the Brazilian Atlantic Forest. However, despite the high importance of this area little research on its herpetofauna has been performed. The present study presents an inventory of the herpetofauna of the region, through bibliographic review, searches in museum collections and field expeditions to the RPPNs Frei Caneca and Pedra D’Antas, in the municipalities of Jaqueira and Lagoa dos Gatos. The conservation status of the amphibians of the region is discussed. Five expeditions, between 2012 and 2013 were made. The methods employed were visual transect surveys, acoustic census and pitfall traps. We recorded a total of 46 amphibian species, belonging to nine families: Craugastoridae (3 spp.), Bufonidae (3 spp.), Ranidae (1 sp.), Hylidae (25 spp.), Leptodactylidae (8 spp.), Odontophrynidae (1 sp.), Hemiphractidae (2 spp.), Phyllomedusidae (2 spp.) and Microhylidae (1 sp.). We recorded 42 species of squamates: 16 species of lizards families Phyllodactylidae (1 sp.), Gekkonidae (1 sp.), Gymnophthalmidae (1 sp.), Polychrotidae (1 sp.), Leiosauridae (1 sp.), Tropiduridae (3 spp.), Dactyloidae (2 spp.), Diploglossidae (2 spp.), Teiidae (2 spp.), Scincidae (1 sp.), and Iguanidae (1 sp.); and 24 species of snakes: Boidae (3 spp.), Colubridae (2 spp.), Dipsadidae (13 spp.), Elapidae (2 spp.), Typhlopidae (1 sp.), and Viperidae (3 spp.). The occurrence of rare and/or threatened species such as the snakes Dipsas sazimai, Lachesis muta and Sibynomorphus sp. and the amphibians Hylomantis granulosa, Chiasmocleis alagoana, Boana freicanecae and Phyllodytes gyrinaethes reinforces the need for conservation measures at this highly threatened region of the Atlantic Forest
- …