440 research outputs found

    Desenvolvimento de recursos didácticos informatizados no âmbito da educação para o desenvolvimento sustentável. o exemplo do courseware SeRe

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    A falta de recursos didácticos informatizados de qualidade para o 1º e 2º Ciclos do Ensino Básico (1º/2º CEB), concebidos no âmbito da Educação para o Desenvolvimento Sustentável (EDS), numa perspectiva de Ensino por Pesquisa, determinou a organização de uma equipa multidisciplinar para o desenvolvimento do «Courseware Sere - O Ser Humano e os Recursos Naturais». Ajustando alguns princípios de desenvolvimento de software, particularmente de Design Centrado no Utilizador (DCU), o trabalho da equipa multidisciplinar, constituída por elementos com diversas competências (ao nível da Didáctica das Ciências, da Tecnologia Educativa, de Design e de Programação), centrou-se no desenvolvimento de um recurso didáctico informatizado que integra várias tipologias de software, nomeadamente simulações e visualizações, com as actividades didácticas. A orientação do recurso, as temáticas propostas e as metodologias e estratégias de exploração privilegiadas fundamentam-se: i) na identificação das orientações nacionais e internacionais da EDS; ii) na identificação das necessidades e interesses dos professores quanto à implementação de actividades com orientação EDS (Sá, 2008; Sá e Martins, 2007), iii) no paradigma de ensino por competências (Cachapuz, Sá-Chaves e Paixão, 2004) e iv) no recurso a um design interactivo centrado no utilizador (Costa, Loureiro, Reis, Sá, Guerra e Vieira, 2009; Guerra, 2007). Neste artigo faz-se uma apresentação do processo de desenvolvimento do recurso didáctico, das temáticas propostas e das metodologias e estratégias de exploração perspectivadas pelos autores do recurs

    Pro-oxidant Activity And Genotoxicity Of The Astronium Fraxinifolium Using Wing Smart And Allium Cepa Test

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    Astronium fraxinifolium is an arboreal species found throughout the Brazilian Cerrado region and used in folk medicine as antimicrobial, anti-hemorrhagic and healing. Pro-oxidant activity of extracts of fraxinifolium rough Relative Electrophoresis Mobility (REM) of Bovine Serum Albumin (BSA) protein in presence of the extract and Cu2+ and also the genotoxic potential through Somatic Mutation and Recombination Test (SMART) and Allium cepa tests has been investigated during this study. In the REM, the extracts acting exclusively on BSA resulted in a band formation with higher molecular weight than BSA, probably due to oxidative action of the extracts. In presence of Cu2+and extracts occurred protein fragmentation due to Cu2+ oxidative action potentiated by the extracts. In SMART test the frequency of mutant spots increases with the increased concentration of extract A. fraxinifolium (50 mg mL-1= 1.40 and 100 mg mL-1 = 2.66). The HB cross shows a decrease in the total of mutant spots frequency for the different treatments (50 mg mL-1 =6.60 and 100 mg mL-1 = 3.25). Evaluation of A cutest demonstrated the following results (concentration extract = chromosomal abnormalities) 1 mg mL-1 = 85,10 mg L-1 = 61 50 mg mL-1 = 53,100 mg mL-1 =33 and MMS 10 mg L-1 = 50. Genotoxic and cytotoxic actions can be explained by the actions of tannins present in its composition. Butthere may be other substances that also act for such results. The genotoxicity in medicinal plants contributes to therapeutic safety warning that although the use of medicinal plants is an inexpensive and non-aggressive method it can cause harmful effects if used incorrectly. © 2016 Rafael Rozolen Teixeria Zafred et al.10427628

    Overcoming adaptive resistance in mucoepidermoid carcinoma through inhibition of the IKK-β/IκBα/NFκB axis

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    Patients with mucoepidermoid carcinoma (MEC) experience low survival rates and high morbidity following treatment, yet the intrinsic resistance of MEC cells to ionizing radiation (IR) and the mechanisms underlying acquired resistance remain unexplored. Herein, we demonstrated that low doses of IR intrinsically activated NFκB in resistant MEC cell lines. Moreover, resistance was significantly enhanced in IR-sensitive cell lines when NFκB pathway was stimulated. Pharmacological inhibition of the IKK-β/IκBα/ NFκB axis, using a single dose of FDA-approved Emetine, led to a striking sensitization of MEC cells to IR and a reduction in cancer stem cells. We achieved a major step towards better understanding the basic mechanisms involved in IR-adaptive resistance in MEC cell lines and how to efficiently overcome this critical problem

    Site-Dilution-Induced Antiferromagnetic Long-Range Order in Two-Dimensional Spin-Gapped Heisenberg Antiferromagnet

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    Effects of the site dilution on spin-gapped Heisenberg antiferromagnets with S=1/2S=1/2 and S=1 on a square lattice are investigated by means of the quantum Monte Carlo method. It is found that effective magnetic moments induced around the diluted sites exhibit the antiferromagnetic long-range order in the medium of spin-singlet pairs. Their microscopic structure is examined in detail and important roles of the higher dimensionality than one on the phenomenon are discussed.Comment: RevTeX, 4 pages, 6 figure

    Effect of bullfrog (Rana catesbeiana) oil administered by gavage on the fatty acid composition and oxidative stress of mouse liver

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    The aim of the present study was to investigate the effects of daily intragastric administration of bullfrog oil (oleic, linoleic and palmitoleic acid-rich oil), corresponding to 0.4% of body weight for four weeks, on fatty acid composition and oxidative stress (lipid peroxidation and catalase activity) in mouse liver. The activities of aspartate aminotransferase (AST), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT), biomarkers of tissue injury, were determined in liver homogenates and serum. The proportions of 18:2n-6, 20:4n-6, 20:5n-3, and 22:6n-3 (polyunsaturated fatty acids, from 37 to 60%) in the total fatty acid content were increased in the liver of the bullfrog oil-treated group (P < 0.05) compared to control. At the same time, a significant decrease in the relative abundance of 14:0, 16:0, and 18:0 (saturated fatty acids, from 49 to 25%) was observed. The hepatic content of thiobarbituric acid reactive substances (TBARS) was increased from 2.3 ± 0.2 to 12.3 ± 0.3 nmol TBA-MDA/mg protein and catalase activity was increased from 840 ± 32 to 1110 ± 45 µmol reduced H2O2 min-1 mg protein-1 in the treated group. Bullfrog oil administration increased AST and ALP activities in the liver (from 234.10 ± 0.12 to 342.84 ± 0.13 and 9.38 ± 0.60 to 20.06 ± 0.27 U/g, respectively) and in serum (from 95.41 ± 6.13 to 120.32 ± 3.15 and 234.75 ± 11.5 to 254.41 ± 2.73 U/l, respectively), suggesting that this treatment induced tissue damage. ALT activity was increased from 287.28 ± 0.29 to 315.98 ± 0.34 U/g in the liver but remained unchanged in serum, whereas the GGT activity was not affected by bullfrog oil treatment. Therefore, despite the interesting modulation of fatty acids by bullfrog oil, a possible therapeutic use requires care since some adverse effects were observed in liver.1491149

    Effect of bullfrog (Rana catesbeiana) oil administered by gavage on the fatty acid composition and oxidative stress of mouse liver

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    The aim of the present study was to investigate the effects of daily intragastric administration of bullfrog oil (oleic, linoleic and palmitoleic acid-rich oil), corresponding to 0.4% of body weight for four weeks, on fatty acid composition and oxidative stress (lipid peroxidation and catalase activity) in mouse liver. The activities of aspartate aminotransferase (AST), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT), biomarkers of tissue injury, were determined in liver homogenates and serum. The proportions of 18:2n-6, 20:4n-6, 20:5n-3, and 22:6n-3 (polyunsaturated fatty acids, from 37 to 60%) in the total fatty acid content were increased in the liver of the bullfrog oil-treated group (P < 0.05) compared to control. At the same time, a significant decrease in the relative abundance of 14:0, 16:0, and 18:0 (saturated fatty acids, from 49 to 25%) was observed. The hepatic content of thiobarbituric acid reactive substances (TBARS) was increased from 2.3 ± 0.2 to 12.3 ± 0.3 nmol TBA-MDA/mg protein and catalase activity was increased from 840 ± 32 to 1110 ± 45 µmol reduced H2O2 min-1 mg protein-1 in the treated group. Bullfrog oil administration increased AST and ALP activities in the liver (from 234.10 ± 0.12 to 342.84 ± 0.13 and 9.38 ± 0.60 to 20.06 ± 0.27 U/g, respectively) and in serum (from 95.41 ± 6.13 to 120.32 ± 3.15 and 234.75 ± 11.5 to 254.41 ± 2.73 U/l, respectively), suggesting that this treatment induced tissue damage. ALT activity was increased from 287.28 ± 0.29 to 315.98 ± 0.34 U/g in the liver but remained unchanged in serum, whereas the GGT activity was not affected by bullfrog oil treatment. Therefore, despite the interesting modulation of fatty acids by bullfrog oil, a possible therapeutic use requires care since some adverse effects were observed in liver

    How Cynara cardunculus ecotypes affect the production of Castelo Branco PDO cheese : a case study

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    Cheese manufacture is a way of preserving a very perishable food, milk. This product is a versatile food that offers various flavours and textures, making it a convenient food and a source of nutrients1. Last available data from Instituto Nacional de Estatística (INE) indicates that the annual dairy consumption reaches 1218 thousand tons in Portugal and the third more consumed dairy product is cheese, with 137 thousand tons per year2. In 2021, the world cheese trade was forecast to rise 4 % to hit the record of 3.6 million tonnes.Programa de Desenvolvimento Rural 2014-2020, PDR2020-101-031009info:eu-repo/semantics/publishedVersio

    Uso da adubação orgânica e cobertura morta na cultura da calêndula (Calendula officinalis L.).

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    A calêndula representa fonte alternativa econômica principalmente para a agricultura familiar. O objetivo do presente trabalho foi avaliar os efeitos da adubação orgânica e do uso da cobertura morta sobre a produção de biomassa e teor de flavonóides totais em plantas de calêndula. O experimento foi realizado no Campus de Montes Claros da Universidade Federal de Minas Gerais, utilizando-se o delineamento em blocos casualizados em esquema fatorial 2x2x4 com quatro repetições: duas épocas de colheita, presença ou ausência de cobertura morta e quatro doses de composto orgânico (0, 30, 60 e 90 t ha-1). As maiores produções de biomassa e flavonóides totais foram verificadas com o aumento das doses de composto orgânico. Para os flavonóides totais o maior teor foi obtido na segunda colheita na presença de cobertura morta
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