Abstract Historically, phenol/croton oil deep chemical peeling has been very effective and has generated excellent results compared to other formulas used in dermatological clinics. However, it can cause serious side effects in patients sensitive to phenol. Therefore, this study aimed to develop a liquid crystalline structure containing croton oil (without phenol) as well as to evaluate the physical characteristics and cytotoxicity of this new system. Rational proportions of the croton oil, purified water, and polyethylene glycol hexadecyl ether were designed through a partial phase diagram to obtain 26 formulations. After macroscopic analysis and polarized light microscopy evaluation, formulations with lamellar liquid crystalline phase (4 samples) were identified and chosen to determine pH, size, polydispersion index (PDI), zeta potential, and rheological behavior. After 48 hours, three samples presented phase separation. Formulation 8 remained stable, but hydroxyethyl cellulose (HEC, 0.5%, w/w) was added to the aqueous phase, to prevent coalescence. Sample 8A exhibited a pH compatible with the skin, nanometric size, narrow PDI, negative zeta potential, and stability throughout the study period. The addition of HEC improved the organization of the system, making the formulation more stable. The oil, fractions of the oil, and the sample exhibited increasing cytotoxicity, respectively. This result could be attributed to the fractionation process of the vegetal matrix, and the surfactant present in the formulation increased the cell membrane permeability. The proposed approach successfully achieved a physically stable liquid crystal system containing croton oil.

Resumo: Este artigo busca compreender como os processos de colonização europeia e de acumulação primitiva do capital estão relacionados à destinação de atividades de cuidado para as mulheres, e a simultânea invisibilidade e desvalorização dessas experiências femininas. À luz de autoras feministas, são discutidos como a expansão do capitalismo e a colonização desencadearam o fortalecimento do patriarcado e a potencialização da divisão sexual do trabalho. Resumo mulheres femininas feministas trabalho

Abstract: This article seeks to understand how the processes of European colonization and primitive capital accumulation are related to the allocation of care activities for women and the simultaneous invisibility and devaluation of these female experiences. In the light of feminist authors, it is discussed how the expansion of capitalism and colonization triggered the strengthening of patriarchy and the potentiation of the sexual division of labor. Abstract experiences authors labor

Resumo As produções escritas de estudantes podem ser objeto de análise com vista à investigação e ao ensino. Neste trabalho, um dos poucos sobre erros e números complexos, analisam-se as produções, elaboradas por estudantes do ensino superior, para uma tarefa de demonstração de um caso particular da identidade do paralelogramo. Num trabalho que pode dar pistas para a prática letiva de professores do ensino secundário e do ensino superior, procura-se classificar os esquemas de demonstração nessas produções, identificar os erros neles cometidos e relacionar estas duas vertentes de análise. A natureza da investigação é qualitativa, recorrendo à análise de conteúdo empregando, por um lado, critérios prévios de categorizações de esquemas de demonstração e, por outro, critérios novos de categorizações de erros. Constatou-se que os estudantes utilizaram, principalmente, esquemas de demonstração de convicção externa, incluídos numa subcategoria nova designada por não válidos no universo, e esquemas de demonstração dedutivos, incluídos num nível novo que se caracteriza por discernimento incipiente da compreensão da tarefa, do contexto matemático, de hipóteses e tese, e dos conhecimentos prévios a mobilizar. Os erros dominantes nas produções estão relacionados à compreensão dos conceitos de linearidade de uma função e de módulo de um número complexo, apresentando-se possíveis explicações para os mesmos. Apesar de não se identificar uma relação propriamente significativa entre os esquemas de demonstração produzidos pelos estudantes e os erros cometidos, obteve-se material para construção e discussão de questões conceituais no âmbito do tópico números complexos.

Abstract The written productions of students can be subjected to analysis for research and teaching purposes. In the present work, one of the few on errors and complex numbers, the productions presented by Higher Education students for a proof task of a particular case of the parallelogram identity are analysed. In a work that may give clues for the teaching practice in High School and Higher Education, we attempt to classify the proof schemes of those productions, to identify the errors and to connect these two strands of analysis. The nature of the research is qualitative, making use of content analysis with, on the one hand, known criteria of categorization of proof schemes and, on the other hand, new criteria of categorization of errors. The students produced, mainly, external conviction proof schemes, included in a new subcategory called not valid in the universe, and deductive proof schemes, included in a new level that is characterized by the inchoate discernment of the comprehension of the task, of the mathematical context, of the hypotheses and thesis, and the previous knowledge that was needed. The dominant errors in the productions, for which possible explanations are presented, are related to the understanding of the concepts of linearity of a function and of modulus of a complex number. Although a significant relation between the proof schemes produced by the students and the errors is not identified, material for the construction and the discussion of concept questions in the context of complex numbers is obtained.

Abstract Introduction: The History of Mathematics (HM) has attracted authors from various fields, given its relevance as a field of research. Among them, mathematical educators seek to understand the contributions HM can give to understand the nature of Mathematics and also how it can be used in teaching in order to promote rich and meaningful learning. In this process, the mathematics’ teacher is a key figure that it is important to know better, namely his conceptions, practices and training processes in HM. Objectives: To know the conceptions and practices of mathematics teachers participating in the TW on the use of HM in the teaching of the discipline, at the beginning of the training; understand the impact of training on the conceptions and practices on MH of the participating mathematics’ teachers. Methods: This study, which is developed in the context of a training workshop (TW), adopts a mixed methodology, based on an on-line questionnaire applied to 12 participating teachers in an TW on MH. Additionally, field notes and documentary records produced by teachers were used. Conclusion: The study allowed us to conclude that when teachers participate in (continuous) training that privileges rich tasks involving HM, framed in specific mathematical programmatic contents, in a reflective and collaborative environment and with experimentation in their practices, they tend to recognize the potentialities of the use of HM in teaching and to value them, introducing it in their practices.

Resumen Introducción: La Historia de las Matemáticas (HM) ha atraído a autores de diversos campos, dada su relevancia como campo de investigación. Entre ellos, los educadores matemáticos buscan entender las contribuciones que la HM puede hacer para entender la naturaleza de las matemáticas y también cómo se puede utilizar en la enseñanza con el fin de promover el aprendizaje rico y significativo. En este proceso, el profesor de matemáticas es una figura clave que es importante conocer mejor, a nivel de sus concepciones, prácticas y procesos de formación en HM. Objetivos: Conocer las concepciones y prácticas de los profesores de matemáticas que participan en la formación sobre el uso del HM en la enseñanza de la disciplina, al comienzo de la formación; comprender el impacto de la formación en los diseños y prácticas de los profesores de Matemáticas participantes en HM. Métodos: El estudio, que se desarrolla en el contexto de un taller de formación (TF), adopta una metodología mixta, basada en la recopilación de un cuestionario en línea a 12 profesores que participan en un TF en HM. Además, se utilizaron notas de campo y registros documentales producidos por profesores. Conclusión: El estudio nos permitió concluir que cuando los profesores participan en una formación (continua) que privilegia tareas ricas que implican HM enmarcadas en contenidos matemáticos programáticos específicos, en un entorno reflexivo y colaborativo y con experimentación en sus prácticas, tienden a reconocer las potencialidades del uso dela HM en la enseñanza y a valorarlos, presentándolos en sus prácticas.

Resumo Introdução: A História da Matemática (HM) tem atraído autores de diversas áreas, dada a sua relevância como campo de investigação. De entre eles, os educadores matemáticos procuram perceber os contributos que a HM pode dar para a compreensão da natureza da Matemática e também como ela pode ser usada no ensino, de modo a promover aprendizagens ricas e significativas. Neste processo, o professor de Matemática é uma figura-chave que importa conhecer melhor, ao nível das suas conceções, práticas e processos de formação em HM. Objetivos: Conhecer as conceções e as práticas dos professores de Matemática participantes na formação sobre a utilização da HM no ensino da disciplina, no início da formação; Compreender o impacto da formação nas conceções e nas práticas dos professores de Matemática participantes, sobre HM. Métodos: O estudo, que se desenvolve no contexto de uma oficina de formação (OF), adota uma metodologia mista, assentando a recolha na aplicação de um questionário on-line a 12 professores participantes numa OF sobre HM. Para além disso, recorreu-se a notas de campo e registos documentais produzidos pelos professores. Conclusão: O estudo permitiu concluir que quando os professores participam em formação (contínua) que privilegia tarefas ricas que envolvem HM enquadrada em conteúdos programáticos matemáticos específicos, num ambiente reflexivo e colaborativo e com experimentação nas suas práticas, tendem a reconhecer as potencialidades do uso da HM no ensino e a valorizá-las, introduzindo-a nas suas práticas.

Abstract The installation of solar parks requires extensive areas and results in soil erosion in many cases. One suitable solution is applying lime to improve soil characteristics, such as mechanical strength, stability, workability, durability, and internal and surface erosion resistance. This soil treatment is of particular importance when dealing with hydraulic structures conceived in the solar park drainage systems. The erodibility tests were performed in a solar complex soil in an EFA apparatus constructed to measure the erosion rate of cohesive and non-cohesive soils in different flow rates. The tests were performed with or without 3% lime addition and two compaction conditions. The experiments indicated that the erodibility of lime-treated soils represents between 26% and 12% of the values obtained from untreated soils and under reduced compaction. The values ranged from 16% to 7% for controlled compaction. The results represent a significant reduction in the soil erodibility treated with lime even with reduced compaction, performing an efficient, economical, and sustainable solution for erosion control.

Resumo Dyckia pseudococcinea é uma espécie endêmica e ameaçada das restingas da Mata Atlântica, uma área sob forte impacto antrópico. Do ponto de vista da conservação, a embriologia vegetal é interessante pela variedade de abordagens para o cultivo in vitro. A partir disso, o presente estudo descreve o endospermogênese de D. pseudococcinea para fornecer dados para estudos de conservação e indicar caracteres que pode contribuir para a sistemática de Pitcairnioideae. Usando análises anatômicas, amostras de flores e frutos em diferentes estágios de desenvolvimento foram analisados. Foi observado o estabelecimento do endosperma primário núcleo e, em seguida, a célula endosperma primária (PEC). Após a expansão do vacúolo central do PEC, núcleos migram para os domínios calazal, periférico e micropilar. Uma celularização centrípeta precoce se inicia na região calazal, caracterizando o endosperma como do tipo cenocítico/multicelular. Com a celularização, o endosperma envolve o embrião. Além disso, na camada mais externa do endosperma, uma camada de aleurona é visível. Essas observações permitiram a identificação de alguns caracteres embriológicos, ajudando a esclarecer as relações sistemáticas de Pitcairnioideae e também do gênero Dyckia, como a presença de hipóstase, a persistência dos antípodas e sinérgides durante as fases iniciais e cenocítico/multicelular da endospermogênese. Tendo assim estabelecido os detalhes da endospermogênese, apresentamos diretrizes para o desenvolvimento de protocolos de cultura in vitro visando à conservação de D. pseudococcinea, uma espécie de bromélia ameaçada de extinção da Mata Atlântica.

Abstract Dyckia pseudococcinea is a threatened species endemic to the restingas of the Atlantic Forest, an area under strong anthropic impact. From the perspective of conservation, plant embryology is interesting by the variety of approaches for in vitro culture of seedlings. With this in mind, the present study describes the endospermogenesis of D. pseudococcinea to provide data for conservation studies and indicate characters that may contribute to the systematics of Pitcairnioideae. Using anatomical analysis, samples of flowers and fruits at different developmental stages were analyzed. We observed the establishment of the primary endosperm nucleus and then the primary endosperm cell (PEC). Upon expansion of the central vacuole of PEC, nuclei migrate to the chalazal, peripheral, and micropylar domains. An early centripetal cellularization begins in the chalazal region, characterizing the endosperm as coenocytic/multicellular type. With cellularization, the endosperm enfolds the embryo. In addition, in the outermost layer of the endosperm, an aleurone layer is visible. These observations allowed some embryological characters to be identified, thus helping to clarify the systematic relationships of Pitcairnioideae and also the genus Dyckia, such as the presence of hypostasis, the persistence of the antipodals and synergids during the early stages of endospermogenesis and coenocytic/multicellular endospermogenesis. Having established the details of endospermogenesis, we then set forth guidelines for the development of in vitro culture protocols aimed at the conservation of D. pseudococcinea, an endangered Bromeliad species of the Atlantic Forest.

Abstract This research explored the potential of Camellia sinensis-derived teas and active compounds to be used as treatments to prevent dentin wear. Human root dentin slabs were randomly assigned to 5 groups (n = 10) as follows: distilled water (DW, control), epigallocatechin-3-gallate (EGCG), theaflavin gallate derivatives (TF), commercial green tea (GT), and commercial black tea (BT). The samples were submitted to a pellicle formation and an erosive cycling model (5x/day, demineralization using 0.01 M hydrochloric acid/60 s) followed by remineralization (human stimulated saliva/60 min) for three days. The samples were treated for 5 min using the test group solutions between the erosive cycles. Dentin changes were assessed with profilometry analysis and FT-Raman spectroscopy. The data regarding wear were analyzed by ANOVA followed by Tukey's test (p < 0.05). EGCG, TF derivatives, and both regular teas significantly suppressed erosive dentin loss (38–47%, p < 0.05). No obvious changes in the Raman spectra were detected in the specimens; however, the DW group had a minor relationship of 2880/2940 cm−1. The phenolic contents in both green and black tea and the important catechins appear to have protective effects on dentin loss.

ABSTRACT The aim of this study was to determine the composition and antioxidant potential of leaves of a new variety of Stevia rebaudiana (Stevia UEM-13). Stevia leaves of UEM-13 contain rebaudioside A as the main glycoside, while most wild Stevia plants contain stevioside. Furthermore can be multiplied by seed, which reduces the cost of plant culture techniques as other clonal varieties are multiplied by buds, requiring sophisticated and expensive seedling production systems. Ethanol and methanol were used in the extraction to determine the bioactive compounds. The methanolic extract was fractionated sequentially with hexane, chloroform, ethyl acetate and isobutanol, and the highest concentration of phenolic compounds and flavonoids was obtained in the ethyl acetate fraction (524.20 mg galic acid equivalent/g; 380.62 µg quercetin equivalent/g). The glycoside content varied greatly among the fractions (0.5% - 65.3%). Higher antioxidant potential was found in the methanol extract and the ethyl acetate fraction with 93.5% and 97.32%, respectively. In addition to being an excellent source for obtaining of extracts rich in glycoside, this new variety can also be used as raw material for the production of extracts or fractions with a significant amount of antioxidant activity and potential to be used as additives in food.

RESUMO Objetivo: Obtenção de um concentrado proteico do soro do leite por meio de processos de separação por membranas, adoçado com rebaudiosídeo A, análise sensorial em humanos e avaliação de propriedades funcionais em modelos de ratos induzidos por estreptozotocina. Métodos: Foram produzidos dois concentrados, mas apenas o segundo, que apresentou teor proteico de 74,3 e 17,3% de lactose, foi utilizado na suplementação de animais diabéticos. Esse concentrado foi obtido a partir da concentração em sistema de osmose reversa (180 Daltons), seguida de nanofiltração em membrana de 500 Daltons e secagem emspray dryer de uma solução a 5% do primeiro concentrado desenvolvido. O concentrado foi adoçado com rebaudiosídeo A (26 mg de rebaudiosídeo A/100 g de concentrado) obtido por meio da extração, separação e purificação das folhas de Stevia rebaudiana. Todos os processos foram realizados no Núcleo de Estudos em Produtos Naturais, da Universidade Estadual de Maringá. Foram estabelecidos três grupos experimentais (n=6): dois de animais diabéticos, um controle e outro suplementado; e um grupo de animais não diabéticos controle. O grupo suplementado recebeu o concentrado adoçado com rebaudiosídeo A na dose de 100 mg/kg peso corporal/dia, por sonda esofágica, por um período de 35 dias. Em todos os grupos, foram avaliadas semanalmente as glicemias de jejum e no estado alimentado, e o peso corporal. Ao final do período de suplementação, os parâmetros plasmáticos de glicose, colesterol total, triglicérides e da frutosamina; os valores séricos de aspartato aminotransferase e alanina aminotransferase e a ingestão hídrica e alimentar foram analisados. Órgãos e tecidos foram retirados e pesados a fim de se avaliarem alterações de massa e anatômicas. Resultados: O produto formulado apresentou 74% de proteínas e 17% de lactose e apresentou perfil sensorial satisfatório por meio da adição de 26 mg de rebaudiosídeo A/100 g de concentrado. A suplementação do produto reduziu a hiperglicemia, os níveis plasmáticos de frutosamina, triglicérides e colesterol total e ainda melhorou o ganho de peso corporal dos ratos diabéticos induzidos. Conclusão: Os processos de separação por membranas utilizados neste estudo proporcionaram a obtenção eficiente de um concentrado proteico do soro do leite, com teor proteico importante, superior a 70% e com baixo teor de lactose. A adição de rebaudiosídeo A ao produto na concentração de 26 mg/100 g de rebaudiosídeo A proporcionou dulçor equivalente ao da sucralose, com perfil sensorial satisfatório, o que indica que esse edulcorante natural não calórico tem potencialidade para substituir os artificiais. O produto obtido (concentrado proteico do soro do leite adoçado com rebaudiosídeo A) apresentou propriedades funcionais importantes, reduzindo alguns distúrbios metabólicos decorrentes dessa síndrome.

ABSTRACT Objective: To develop a natural dietary product with functional benefits for diabetic patients. Whey protein concentrate was obtained through the separation membrane processes and sweetened with rebaudioside A. This product was submitted to sensory testing in humans and used to evaluate possible functional properties in male Wistar rats models with diabetesMellitus induced by streptozotocin. Methods: Two concentrates were produced. Only the second showed protein content of 74.3 and 17.3% of lactose was used as supplementation in induced diabetic rats. This concentrate was obtained from the concentration by reverse osmosis system (180 k Daltons), followed by nanofiltration in a 500 k Daltons membrane and spray drying at 5.0% solution of the first concentrate developed. The concentrate was sweetened with rebaudioside A (rebaudioside A 26 mg/100 g concentrate). All procedures were performed at the Center for Studies in Natural Products, at the Universidade Estadual de Maringá. Three experimental groups were established (n=6): two groups of diabetic animals, one control group and one supplemented group; and a control group of normal mice (non-diabetic). The supplemented group received concentrates sweetened with rebaudioside A in a dose of 100 mg/kg bw/day by an esophageal tube for 35 days. Fasting, the fed state and body weight were assessed weekly for all groups. At the end of the supplementation period, the following were analyzed: plasma parameters of glucose, total cholesterol, triglycerides and fructosamine; the serum levels of aspartate aminotransferase and alanine aminotransferase, water and food intake. Organs and tissues were removed and weighed to assess mass and anatomical changes. Results: The product presented 74% of proteins and 17% of lactose and showed satisfactory sensory testing by the addition of 26 mg of rebaudioside A/100 g concentrate. Supplementation of the product reduced hyperglycemia, plasma fructosamine levels, triglycerides and total cholesterol, and improved body weight gain of streptozotocin-induced diabetic rats. Conclusion: Whey protein concentrate with substantial content of protein (above 70%) and low lactose was obtained through the membrane separation processes. The addition of rebaudioside A at the concentration of 26 mg/100 g rebaudioside A proved to be as sweet as sucralose with satisfactory sensory testing, which indicates that this is a non-caloric natural sweetener that can replace artificial sweeteners. The product (whey protein concentrate sweetened with rebaudioside A) presented important functional properties and reduced the metabolic disorders caused by the syndrome.

Objetivo: Descrever o desenvolvimento de um objeto virtual de aprendizagem sobre o raciocínio diagnóstico em enfermagem aplicado ao sistema tegumentar em uma universidade pública do Piauí. Método: Pesquisa metodológica aplicada de produção tecnológica que utilizou o referencial pedagógico da educação problematizadora; a metodologia para desenvolvimento do objeto de aprendizagem seguiu as etapas de análise, design, desenvolvimento, implementação e avaliação preconizadas pelo design instrucional contextualizado, e a taxonomia revisada de Bloom foi utilizada para elencar os objetivos educacionais. Resultados: Os quatro módulos do objeto de aprendizagem desenvolvido foram inseridos na plataforma educacional do Moodle. Os pressupostos teóricos permitiram conceber um material educativo virtual o qual se configura como instrumento importante para a promoção de uma aprendizagem efetiva no âmbito educacional da enfermagem. Conclusão: Espera-se agregar valor às práticas de ensino da enfermagem mediante utilização de objetos virtuais de aprendizagem no ensino do raciocínio diagnóstico aplicado à pele e aos anexos cutâneos.

Objective: To describe the creation of a digital learning object for diagnostic reasoning in nursing applied to the integumentary system at a public university of Piaui. Method: A methodological study applied to technological production based on the pedagogical framework of problem-based learning. The methodology for creating the learning object observed the stages of analysis, design, development, implementation and evaluation recommended for contextualized instructional design. The revised taxonomy of Bloom was used to list the educational goals. Results: The four modules of the developed learning object were inserted into the educational platform Moodle. The theoretical assumptions allowed the design of an important online resource that promotes effective learning in the scope of nursing education. Conclusion: This study should add value to nursing teaching practices through the use of digital learning objects for teaching diagnostic reasoning applied to skin and skin appendages.

Objetivo: Describir el desarrollo de un objeto virtual de aprendizaje acerca de la enfermería con razonamiento diagnóstico aplicado al sistema tegumentario en una universidad pública en Piauí. Método: Investigación metodológica aplicada en la producción tecnológica que utiliza el marco pedagógico de la enseñanza basada en problemas, la metodología para el desarrollo del aprendizaje objeto siguió las etapas de análisis, diseño, desarrollo, implementación y evaluación recomendado por el diseño instruccional y contextualizada utilizado la taxonomía revisada de Bloom para enumerar las metas educativas. Resultados: Los cuatro módulos desarrollados objeto de aprendizaje se insertaron en la plataforma educativa Moodle. Los supuestos teóricos permitieron diseñar un material educativo virtual que se configura como una herramienta importante para promover un aprendizaje eficaz en la educación de contexto de la enfermería. Conclusión: Se espera agregar valor a las prácticas de enseñanza de enfermería mediante el uso de objetos virtuales de aprendizaje en la enseñanza del razonamiento diagnóstico aplicado a la piel y de la piel apéndices.

Objective: To describe the creation of a digital learning object for diagnostic reasoning in nursing applied to the integumentary system at a public university of Piaui. Method: A methodological study applied to technological production based on the pedagogical framework of problem-based learning. The methodology for creating the learning object observed the stages of analysis, design, development, implementation and evaluation recommended for contextualized instructional design. The revised taxonomy of Bloom was used to list the educational goals. Results: The four modules of the developed learning object were inserted into the educational platform Moodle. The theoretical assumptions allowed the design of an important online resource that promotes effective learning in the scope of nursing education. Conclusion: This study should add value to nursing teaching practices through the use of digital learning objects for teaching diagnostic reasoning applied to skin and skin appendages.

Objetivo: Describir el desarrollo de un objeto virtual de aprendizaje acerca de la enfermería con razonamiento diagnóstico aplicado al sistema tegumentario en una universidad pública en Piauí. Método: Investigación metodológica aplicada en la producción tecnológica que utiliza el marco pedagógico de la enseñanza basada en problemas, la metodología para el desarrollo del aprendizaje objeto siguió las etapas de análisis, diseño, desarrollo, implementación y evaluación recomendado por el diseño instruccional y contextualizada utilizado la taxonomía revisada de Bloom para enumerar las metas educativas. Resultados: Los cuatro módulos desarrollados objeto de aprendizaje se insertaron en la plataforma educativa Moodle. Los supuestos teóricos permitieron diseñar un material educativo virtual que se configura como una herramienta importante para promover un aprendizaje eficaz en la educación de contexto de la enfermería. Conclusión: Se espera agregar valor a las prácticas de enseñanza de enfermería mediante el uso de objetos virtuales de aprendizaje en la enseñanza del razonamiento diagnóstico aplicado a la piel y de la piel apéndices.

Objetivo: Descrever o desenvolvimento de um objeto virtual de aprendizagem sobre o raciocínio diagnóstico em enfermagem aplicado ao sistema tegumentar em uma universidade pública do Piauí. Método: Pesquisa metodológica aplicada de produção tecnológica que utilizou o referencial pedagógico da educação problematizadora; a metodologia para desenvolvimento do objeto de aprendizagem seguiu as etapas de análise, design, desenvolvimento, implementação e avaliação preconizadas pelo design instrucional contextualizado, e a taxonomia revisada de Bloom foi utilizada para elencar os objetivos educacionais. Resultados: Os quatro módulos do objeto de aprendizagem desenvolvido foram inseridos na plataforma educacional do Moodle. Os pressupostos teóricos permitiram conceber um material educativo virtual o qual se configura como instrumento importante para a promoção de uma aprendizagem efetiva no âmbito educacional da enfermagem. Conclusão: Espera-se agregar valor às práticas de ensino da enfermagem mediante utilização de objetos virtuais de aprendizagem no ensino do raciocínio diagnóstico aplicado à pele e aos anexos cutâneos.

Background Clavulanic acid is an important beta-lactamase inhibitor produced as a secondary metabolite by the actinomycete Streptomyces clavuligerus. Clavulanic acid is chemically unstable; therefore, it is degraded during bacterial cultivation. In this work, the adsorbents clinoptilolite, activated carbon, calcined hydrotalcite, and Amberlite IRA 400 anionic exchange resin were studied in terms of their ability to adsorb clavulanic acid during extractive fermentation, in order to prevent product degradation and avoid product concentrations reaching inhibitory levels. Adsorption assays were used to investigate the effect of pH, and the decrease in the clavulanic acid concentration in the culture broth was measured for each adsorbent. Results IRA 400 was found to be most effective, with 78% adsorption of clavulanic acid. The maximum production of clavulanic acid in Erlenmeyer flask cultures increased 86% in terms of mass of CA, and 248% in cumulative CA concentration, with the use of Amberlite IRA 400 as adsorbent in extractive fermentation, compared to control fermentation performed without product removal. Conclusions The results indicated that extractive fermentation using a solid phase could be an important way of enhancing clavulanic acid titers. It was also possible to show that clavulanic acid acts as an inhibitor of its own synthesis.

Este estudo apresentou diferenças anatômicas relacionadas às espécies Piper lepturum. var. lepturum e P. lepturumvar. angustifolium, que são às vezes consideradas como variedades e em outros casos como sinônimos. Para a análise histológica, folhas completamente expandidas foram coletadas e para análise ao microscópio eletrônico de varredura (MEV), pequenos fragmentos de ambas as faces de nervura central foram fixados. As duas espécies revelaram diferenças na anatomia vegetal, e foi observado que no pecíolo de P. lepturum var. lepturum há presença de alas persistentes e células epidérmicas papilosas, e estas características estão ausentes em P. lepturum var. angustifolium. Houve também a presença de ráfides tanto no pecíolo quanto na lâmina foliar apenas em P. lepturum var. angustifolium, diferenciando as duas espécie. Estudos recentes mostram a importância da anatomia vegetal com espécies onde há questões relacionadas à delimitação taxonômica.

This study showed anatomical differences related to Piper lepturumvar. lepturum and P. lepturum var. angustifolium species, sometimes considered varieties and in other cases synonyms. For histological analysis, fully expanded leaves were collected and for analysis by scanning electron microscope (SEM), fragments from the midrib were fixed on both leaf surfaces. The two species revealed differences in plant anatomy and it was observed that the stem of P. lepturum var. lepturum showed persistent wings and papillary epidermal cells, and these characters are absent in P. lepturum var. angustifolium. There was also the presence of raphides only in the lamina leaf and petiole of P. lepturum var. angustifolium, differentiating the two species. Recent studies have shown the importance of plant anatomy with species where there are issues related to taxonomic delimitation.

Community-level network studies suggest that seed dispersal networks may share some universal properties with other complex systems. However, most of the datasets used so far in those studies have been strongly biased towards temperate birds, including not only dispersers, but also seed predators. Recent evidence from multi-taxon networks suggests that seed dispersal networks are not all alike and may be more complex than previously thought. Here, we used network theory to evaluate seed dispersal in a strongly impacted Atlantic Forest fragment in northeastern Brazil, where bats and birds are the only extant dispersers. We hypothesized that the seed dispersal network should be more modular then nested, and that the dispersers should segregate their services according to dispersal syndromes. Furthermore, we predicted that bat and bird species that are more specialized in frugivory would be more important for maintaining the network structure. The mixed network contained 56 plant species, 12 bat species, and eight bird species, and its structure was more modular (M = 0.58) then nested (NODF = 0.21) compared with another multi-taxon network and 21 single-taxon networks (with either bats or birds). All dispersed fruits had seeds smaller than 9 mm. Bats dispersed mainly green fruits, whereas birds dispersed fruits of various colors. The network contained eight modules: five with birds only, two with bats only, and one mixed. Most dispersers were peripheral, and only specialized frugivores acted as hubs or connectors. Our results strongly support recent studies, suggesting that seed dispersal networks are complex mosaics, where different taxa form separate modules with different properties, which in turn play complementary roles in the maintenance of the associated ecosystem functions and services.

Sweeteners based on stevia extract contain a series of diterpene glycosides derivatives from steviol, standing out the rebaudioside-A. There is no tabletop sweeteners in the market formulated purely with rebaudioside-A yet, so its use in foods depends on the development of new products followed by physicochemical and sensory evaluations. This work presents the formulation of a diet strawberry jam dyed with cranberry juice and sweetened with rebaudioside-A purified from stevia plants of the lineage UEM-320 developed in the Centro de Estudos de Produtos Naturais da Universidade Estadual de Maringá. Evaluations of physicochemical properties, microbiological and sensory characteristics were carried out for the product in comparison with a control sweetened with equal amount of sucralose. The results showed that the physicochemical characteristics of the sample and the control are not significantly different and the supplementation with cranberry juice increased both color and total phenolic content in both samples. The sensory acceptability indicated a significant preference for the formulation sweetened with 100% of rebaudioside-A, only in the items flavor and purchase intent. We concluded that rebaudioside-A has a better sensory performance than sucralose, even this last one being 1.33 fold sweeter than rebaudioside-A.