O objetivo desta pesquisa consiste em investigar o significado da avaliação em matemática na perspectiva histórico-cultural, focalizando a teoria da atividade. Para o desenvolvimento dessa investigação, foi formado o grupo colaborativo da Oficina Pedagógica de Matemática de Ribeirão Preto (OPM/RP), constituído por professoras da Educação Infantil e séries iniciais do Ensino Fundamental, as quais foram sujeitos da pesquisa. A função principal do grupo colaborativo foi proporcionar uma formação orientada às professoras sobre o ensino de matemática na perspectiva histórico-cultural, com o intuito de levantar dados sobre o processo de apropriação dos conhecimentos matemáticos pelas docentes. O processo formativo, pautado nos pressupostos da Atividade Orientadora de Ensino, privilegiou a apresentação de situações-problema, cujas soluções possibilitaram a elaboração de conhecimentos, referentes não apenas aos conteúdos matemáticos, mas, também, à prática docente: ensinar, aprender e avaliar em matemática. Na análise dos dados, utilizamos o conceito de isolado (CARAÇA, 1989, MOURA, 2000) como princípio teórico-metodológico para a compreensão do fenômeno em desenvolvimento. Os dados foram organizados em três isolados aprendizagem docente, organização do ensino e prática pedagógica, tendo em vista a relação de interdependência e fluência entre os mesmos. Na relação entre a aprendizagem docente (apropriação dos conceitos teórico-metodológicos sobre o ensino de matemática), a organização do ensino (como elaborar atividade de ensino para que os alunos se apropriem dos conceitos) e a prática pedagógica (como colocar os conceitos teórico-metodológicos em ação na sala de aula) é que o professor se desenvolve profissionalmente, isto é, aprende a ser professor em um contínuo processo formativo. A síntese sobre o processo de aprendizagem docente foi importante para a sistematização dos elementos norteadores da avaliação em matemática na perspectiva da teoria histórico-cultural. Os resultados evidenciaram que a avaliação constitui-se em um constante processo de análise e síntese e seu direcionamento é dado pelo objetivo da atividade de ensino elaborada pelo professor, ou seja, sua intencionalidade pedagógica. A característica principal da avaliação consiste no acompanhamento do processo de ensino e aprendizagem, por meio da análise do sistema de atividade, na dinâmica entre a atividade de ensino e a atividade de aprendizagem, considerando os elementos constitutivos da atividade (necessidade, motivos, objetivos, ações e operações). Por meio da análise das ações de ensino e de aprendizagem, tendo como parâmetros as características do pensamento teórico (reflexão, análise e planificação teórica), concluímos que a avaliação é mediadora entre a atividade de ensino elaborada pelo professor e a atividade de aprendizagem realizada pelos escolares. / This research aims to investigate the meaning of evaluation in mathematics from the historical-cultural perspective, focusing on the activity theory. In order to develop the investigation, a collaborative group was formed from the Oficina Pedagógica de Matemática de Ribeirão Preto São Paulo (Math Pedagogic Workshop of Ribeirão Preto OPM/RP), constituted by teachers of Educação Infantil (Brazilian Primary Education) and teachers of the first years of Ensino Fundamental (Brazilian Secondary Education), which were participants of this research. The main role of the collaborative group was to offer an oriented development to the teachers about the teaching of mathematics from the historical-cultural perspective, aiming at collecting data on the process of appropriation of mathematical knowledge by the teachers. The development process, based on the premises of the Teaching Oriented Activity, privileged the introduction of problem-solving situations, whose solutions allowed the elaboration of knowledge, referring not only to math contents, but also to the teaching practice: teaching, learning and evaluating in mathematics. In analyzing data, we used the concept of isolated (CARAÇA, 1989, MOURA, 2000) as a theoreticalmethodological principle to understand the phenomenon under development. Data were organized into three isolated teachers learning, teaching organization and pedagogical practice, having in mind the relationship of interdependency and fluency among them. It is in the relationship among the teachers learning (appropriation of theoretical-methodological concepts on the teaching of mathematics), the organization of teaching (how to elaborate the teaching activity so that students can appropriate concepts) and the pedagogical practice (how to put theoretical-methodological concepts into practice in the classroom) that the teacher develops professionally, that is, learns to become a teacher through a continuous developing process. The synthesis about the teachers learning process was important to systematize the guiding elements of evaluation in mathematics from the historical-cultural perspective. Results showed that evaluation is constituted of a continuous process of analysis and synthesis, and its north is set by the aim of the teaching activity elaborated by the teacher, that is, his/her pedagogical intentionality. The main characteristic of evaluation lies on keeping track of the teaching and learning process, by means of the analysis of the activity system, along the dynamics between the teaching activity and the learning activity, taking into consideration the activity constitutive elements (need, reasons, objectives, actions and operations). By analyzing the actions of teaching and the actions of learning, having as parameters the characteristics of the theoretical thought (reflection, analysis and theoretical rationalization), we conclude that evaluation is a mediator between the teaching activity elaborated by the teacher and the learning activity performed by the school students.

Made available in DSpace on 2014-12-17T14:03:34Z (GMT). No. of bitstreams: 1 LeandroSC_DISSERT_1-68.pdf: 3005513 bytes, checksum: 4d385177273793fb97add8fa79a198b9 (MD5) Previous issue date: 2012-03-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The coast of Rio Grande do Norte has more than 100 species of seaweed, mostly unexplored regarding their pharmacological potential. The sulfated polysaccharides (PS) are by far the more seaweed compounds studied, these present a range of biological properties, such as anticoagulant activity, anti-inflammatory, antitumor and antioxidant properties. In this study, we extract sulfated polysaccharide rich-extracts of eleven algae from the coast of Rio Grande do Norte (Dictyota cervicornis; Dictiopterys delicatula; Dictyota menstruallis; Dictyota mertensis; Sargassum filipendula; Spatoglossum schr?ederi; Gracilaria caudata; Caulerpa cupresoides; Caulerpa prolifera; Caulerpa sertularioides e Codim isthmocladum), and these were evaluated for the potential anticoagulant, antioxidant and antiproliferative. All polysaccharide extracts showed activity for anticoagulant, antioxidant and/or antiproliferative activity, especially D. delicatula and S. filipendula, which showed the most prominent pharmacological potential, thereby being chosen to have their sulfated polysaccharides extracted. By fractionating method were obtained six fractions rich in sulfated polysaccharides to the algae D. delicatula (DD-0,5V, DD-0, 7V, DD-1,0v, DD-1,3v, DD-1,5v and DD-2,0) and five fractions to the alga S. filipendula (SF-0,5V, SF-0,7V, SF-1,0v, SF-1,5v and SF-2,0v). For the anticoagulant assay only the fractions of D. delicatula showed activity, with emphasis on DD-1, 5v that presented the most prominent activity, with APTT ratio similar to clexane? at 0.1 mg/mL. When evaluated the antioxidant potential, all fractions showed potential in all tests (total antioxidant capacity, hydroxyl and superoxide radicals scavenging, ferrous chelation and reducing power), however, the ability to chelate iron ions appears as the main mechanism antioxidant of sulfated polysaccharides from seaweed. In antiproliferative assay, all heterofucanas showed dose-dependent activity for the inhibition of cell proliferation of HeLa, however, with the exception of SF-0,7V, SF- 1,0v and SF-1,5v, all fractions showed antiproliferative activity against MC3T3, a normal cell line. The heterofucana SF-1,5V had its antiproliferative mechanism of action evaluated. This heterofucan induces apoptosis in HeLa cells by a pathway caspase independent, promoting the release of apoptosis Inducing Factor (AIF) in the cytosol, which in turn induces chromatin condensation and DNA fragmentation into 50Kb fragments. These results are significant in that they provide a mechanistic framework for further exploring the use of SF-1.5v as a novel chemotherapeutics against human cervical cancer. / O litoral do Rio Grande do Norte apresenta mais de 100 esp?cies de macroalgas marinhas, a maioria delas ainda n?o explorada quanto ao seu potencial farmacol?gico. Os polissacar?deos sulfatados (PS) s?o de longe os compostos de macroalgas marinhas mais estudados, sendo atribu?da a estes uma gama de propriedades biol?gicas, como: atividade anticoagulante, antiinflamat?ria, antitumoral e antioxidante. Neste trabalho, obteve-se extratos ricos em polissacar?deos de onze algas do litoral do Rio Grande do Norte (Dictyota cervicornis; Dictiopterys delicatula; Dictyota menstruallis; Dictyota mertensis; Sargassum filipendula; Spatoglossum schr?ederi; Gracilaria caudata; Caulerpa cupresoides; Caulerpa prolifera; Caulerpa sertularioides e Codium isthmocladum), e estas foram avaliadas quanto ao seu potencial anticoagulante, antioxidante e antiproliferativo frente ? linhagem celular tumoral HeLa. Todos os extratos polissacar?dicos apresentaram atividades anticoagulante, antioxidante e/ou antiproliferativa, com destaque para os das algas D. delicatula e S. filipendula, que apresentaram os maiores ?ndices de potencial farmacol?gico, sendo, portanto, escolhidas para serem submetidos a passos posteriores de purifica??o de seus polissacar?deos sulfatados. Atrav?s do fracionamento com volumes crescentes de acetona foram obtidas seis fra??es ricas em polissacar?deos sulfatados da alga D. delicatula (DD-0,5v, DD-0,7v, DD-1,0v, DD-1,3v, DD-1,5v e DD-2,0v) e cinco fra??es da alga S. filipendula (SF-0,5v, SF- 0,7v, SF-1,0v, SF-1,5v e SF-2,0v). An?lises f?sico-qu?micas mostraram que estas s?o ricas em heterofucanas sulfatadas. Apenas as fra??es da alga D. delicatula apresentaram atividade anticoagulante, com destaque para DD-1,5v que apresentou a atividade mais proeminente com raz?o de APTT semelhante ? clexane?, f?rmaco anticoagulante comercial. Quando avaliadas com rela??o ao potencial antioxidante todas as fra??es apresentaram atividade em todos os testes realizados (Capacidade antioxidante total, sequestro de radicais super?xido e hidroxila, quela??o f?rrica e atividade redutora), entretanto, a capacidade de quela??o de ?ons ferro aparece como o principal mecanismo antioxidante dos polissacar?deos sulfatados dessas macroalgas marinhas. No ensaio antiproliferativo, todas as heterofucanas apresentaram atividades dose-dependente para a inibi??o da prolifera??o celular de HeLa, entretanto, as fra??es SF-0,7v, SF-1,0v e SF-1,5v apresentaram atividade espec?fica para esta linhagem celular, n?o inibindo a prolifera??o da linhagem celular normal MC3T3, sendo a heterofucana SF-1,5v escolhida para ter seu mecanismo de a??o antiproliferativo determinado. SF-1,5v induz a apoptose em c?lulas HeLa principalmente atrav?s de uma via independente da ativa??o das caspases, promovendo a libera??o do Fator Indutor da Apoptose (AIF) no citosol, que por sua vez induz a condensa??o da cromatina e fragmenta??o do DNA em fragmentos de 50Kb. Este trabalho ? o primeiro relato mostrando uma heterofucana cujo principal mecanismo antiproliferativo ? a libera??o de AIF mitocondrial para o citosol, o que torna SF-1,5v um promissor f?rmaco na terapia antitumoral, possibilitando uma alternativa aos quimioter?picos tradicionais.

Cumarinas são estruturas promissoras e diversas atividades biológicas têm sido atribuídas a esses metabólitos secundários vegetais. Estudos sugerem que o mecanismo antifúngico desses compostos esteja correlacionado com a atividade antioxidante. A reação da tirosinase, que produz radicais livres, está envolvida no processo de melanização do fungo Sporothrix schenckii, o causador de micose subcutânea de maior incidência no sul do Brasil. A inibição dessa enzima foi recentemente reportada para extrato de Pterocaulon (Asteraceae), planta rica em cumarinas e usada na medicina tradicional do Brasil para tratamento tópico de micoses e na medicina popular da Argentina como anticâncer. O objetivo desse trabalho foi investigar in vitro a atividade antifúngica, correlacionando-a com atividade antioxidante, de extratos de espécies de Pterocaulon e de 6,7-metilenodioxicumarinas isoladas e também de 4-metilcumarinas obtidas por síntese, bem como a investigação da atividade citotóxica de algumas destas moléculas. As 6,7-metilenodioxicumarinas foram isoladas de P. balansae e P. lorentzii, enquanto que as 4-metilcumarinas foram sintetizadas via Pechmann por micro-ondas. A atividade antifúngica contra Sporotrix schenckii foi realizada conforme manual do Clinical and Laboratory Standards Institute. O estudo das propriedades eletroquímicas foi obtido por voltametria cíclica e a capacidade antioxidante pelo método espectofotométrico DPPH (1,1-difenil-2-picrilhidrazil) e pelo método fluorimétrico ACAP contra radicais peroxil. A análise dessa atividade mostrou que os extratos metanólicos de espécies de Pterocaulon (P. polystachyum, P. balansae, P. lorentzii, P. lanatum e P. cordobense) foram ativos frente às cepas do fungo S. schenckii, sendo o extrato de P. polystachyum o mais ativo, apresentando Concentração Inibitória Mínima (CIM) compreendida entre 156 e 312 μg/mL. O fracionamento dos extratos lipofílicos de P. balansae e P. lorentzii levou ao isolamento de três metilenodioxicumarinas. Dados cristalográficos da 5-metóxi-6,7-metilenodioxicumarina, inéditos, foram depositados no Cambridge Crystallographic Data Centre 779123. As cumarinas sintéticas foram obtidas em rendimentos satisfatórios (98-30%) e em reduzido tempo de reação (5-20 min). O screening destas cumarinas frente às cepas do fungo S. schenckii revelou que 5-carboxi-6,7-diidroxi-4-metilcumarina, com CIM de 66 μM e Concentração Fungicida Mínima de 246 μM, foi o composto mais ativo. Essa cumarina apresentou sinergismo com a Anfotericina B, sendo sua CIM reduzida para 15 μM. A atividade antifúngica desses compostos pode estar correlacionada com a atividade antioxidante. O composto 5-carboxi-6,7-diidroxi-4-metilcumarina foi o mais ativo mostrando elevada capacidade antioxidante frente aos radicais DPPH com valores de IC50 de 17,49 μM e elevada atividade frente ao radical peroxil. Além disso, apresentou um potencial de oxidação de 0,4 V sugerindo atividade antioxidante. Baseado nos ensaios antioxidante e antifúngico foi possível observar que a presença de grupamentos hidroxilas no C-7 e C-8 do anel cumarínico, assim como a adição de grupamento polar no C-5 favoreceu ambas as atividades antifúngica e antioxidante. Na segunda etapa desse trabalho foi avaliada a citotoxicidade das cumarinas isoladas e algumas cumarinas simples, disponíveis comercialmente, pelo método Metil Tiazol Tetrazólio (MTT) usando linhagens de glioma humano (U138-MG) e de ratos (C6). Foi observado que as 6,7-metilenodioxicumarinas causaram uma significativa redução na viabilidade celular, sugerindo uma influência positiva do grupamento metilenodioxi sobre essa atividade. O composto 5-metóxi-6,7-metilenodioxicumarina foi o mais promissor (IC50= 34,6 μM e IC50= 31,6 μM para C6 e U-138 MG, respectivamente). Como desfecho desse trabalho, pode-se concluir que as cumarinas apresentaram uma atividade inibitória frente ao crescimento celular de linhagens de glioma e um efeito fungicida sobre S. schenckii, resultados estes que corroboram com o uso popular dessas plantas. / Coumarins are promising structures and diverse biological activities have been attributed to these secondary plant metabolites. Studies suggest that the mechanism of antifungal compounds is correlated with antioxidant activity. The reaction of tyrosinase, which produces free radicals, is involved in the process of melanization of the fungus Sporothrix schenckii, the agent of subcutaneous mycosis with the highest incidence in southern Brazil. The inhibition of this enzyme has recently been reported to extract Pterocaulon (Asteraceae) This plant is rich in coumarins and used in traditional medicine in Brazil for topical treatment of fungal infections and in folk medicine of Argentina as anticancer. The aim of this study was to investigate the in vitro antifungal activity and correlation with its antioxidant properties and cytotoxic activities of extracts of some species of Pterocaulon, as well as the isolated coumarins, and 4-methylcoumarin analogs obtained by synthesis. The 6.7-methylenedioxycoumarins were isolated from P. balansae and P. lorentzii, while the 4-methylcoumarins were synthesized via Pechmann reaction using microwave. The antifungal activity against Sporothrix schenckii was performed as indicated in the Manual of Clinical and Laboratory Standards Institute. A study of the electrochemical properties of coumarins was performed by cyclic voltammetry, by the method of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and against peroxyl radicals (ACAP) by fluorometric method. The analysis showed that the antifungal activity of the methanol extracts of Pterocaulon species (P. polystachyum, P. balansae, P. lorentzii, P. lanatum and P. cordobense) were active against the strains of the fungus S. schenckii, being the extract of P. polystachyum the most active, presenting Minimum Inhibitory Concentration (MIC) compressed between 156 and 312 μg/mL. The fractionation of lipophilic extracts of P. balansae and P. lorentzii led to the isolation of three methylenedioxycoumarins. The crystallographic data of 5-methoxy-6,7-methylenedioxycoumarin were deposited at the Cambridge Crystallographic Data Center 779123. The synthetic coumarins were obtained in satisfactory yields (98-30%) and reduced reaction time (5-20 min). The screening of these coumarins against strains of the fungus S. schenckii revealed that the 5-carboxy-6,7-dihydroxy-4-methylcoumarin was the most active compound, presenting MIC of 66 μM and Minimum Fungicidal Concentration of 246 μM. This coumarin showed synergism with Amphotericin B, and its MIC was reduced to 15 μM. The antifungal activity of phenolic compounds could be related to its antioxidant activities. The compound 5-carboxy-6,7-dihydroxy-4-methylcoumarin was again the most active with IC50 value of 17.49 μM, showing the highest capacity to deplete the radicals DPPH and ACAP, moreover present a oxidation potential of 0.4 V suggesting antioxidant activity. Based on the antioxidant and antifungal tests it was observed that the presence of hydroxyl groups at C-7 and C-8 of the coumarin ring and the addition of polar grouping at C-5 favored both antifungal and antioxidant activities.In the second part of this work, it was evaluated the cytotoxicity of the Pterocaulon compounds and some commercially available coumarins, with simple structure. The cytotoxic potential was determined by Methyl Thiazole Tetrazolium (MTT) test using strains of human glioma (U138-MG) and rat (C6). It was observed that the 6,7-methylenedioxycoumarins caused a significant reduction in cell viability, suggesting a positive influence of the methylenedioxy group in this activity. The compound 5-methoxy-6,7-methylenedioxycoumarin was the most promising (IC50 = 34.6 μM and IC50 = 31.6 μM for C6 and U-138 MG, respectively). In conclusion, this work it was demonstrated that some coumarins showed an inhibitory activity against the growth of glioma cell lines and a fungicidal effect on the S. schenckii. These results corroborate the popular use of these plants.

Cumarinas são estruturas promissoras e diversas atividades biológicas têm sido atribuídas a esses metabólitos secundários vegetais. Estudos sugerem que o mecanismo antifúngico desses compostos esteja correlacionado com a atividade antioxidante. A reação da tirosinase, que produz radicais livres, está envolvida no processo de melanização do fungo Sporothrix schenckii, o causador de micose subcutânea de maior incidência no sul do Brasil. A inibição dessa enzima foi recentemente reportada para extrato de Pterocaulon (Asteraceae), planta rica em cumarinas e usada na medicina tradicional do Brasil para tratamento tópico de micoses e na medicina popular da Argentina como anticâncer. O objetivo desse trabalho foi investigar in vitro a atividade antifúngica, correlacionando-a com atividade antioxidante, de extratos de espécies de Pterocaulon e de 6,7-metilenodioxicumarinas isoladas e também de 4-metilcumarinas obtidas por síntese, bem como a investigação da atividade citotóxica de algumas destas moléculas. As 6,7-metilenodioxicumarinas foram isoladas de P. balansae e P. lorentzii, enquanto que as 4-metilcumarinas foram sintetizadas via Pechmann por micro-ondas. A atividade antifúngica contra Sporotrix schenckii foi realizada conforme manual do Clinical and Laboratory Standards Institute. O estudo das propriedades eletroquímicas foi obtido por voltametria cíclica e a capacidade antioxidante pelo método espectofotométrico DPPH (1,1-difenil-2-picrilhidrazil) e pelo método fluorimétrico ACAP contra radicais peroxil. A análise dessa atividade mostrou que os extratos metanólicos de espécies de Pterocaulon (P. polystachyum, P. balansae, P. lorentzii, P. lanatum e P. cordobense) foram ativos frente às cepas do fungo S. schenckii, sendo o extrato de P. polystachyum o mais ativo, apresentando Concentração Inibitória Mínima (CIM) compreendida entre 156 e 312 μg/mL. O fracionamento dos extratos lipofílicos de P. balansae e P. lorentzii levou ao isolamento de três metilenodioxicumarinas. Dados cristalográficos da 5-metóxi-6,7-metilenodioxicumarina, inéditos, foram depositados no Cambridge Crystallographic Data Centre 779123. As cumarinas sintéticas foram obtidas em rendimentos satisfatórios (98-30%) e em reduzido tempo de reação (5-20 min). O screening destas cumarinas frente às cepas do fungo S. schenckii revelou que 5-carboxi-6,7-diidroxi-4-metilcumarina, com CIM de 66 μM e Concentração Fungicida Mínima de 246 μM, foi o composto mais ativo. Essa cumarina apresentou sinergismo com a Anfotericina B, sendo sua CIM reduzida para 15 μM. A atividade antifúngica desses compostos pode estar correlacionada com a atividade antioxidante. O composto 5-carboxi-6,7-diidroxi-4-metilcumarina foi o mais ativo mostrando elevada capacidade antioxidante frente aos radicais DPPH com valores de IC50 de 17,49 μM e elevada atividade frente ao radical peroxil. Além disso, apresentou um potencial de oxidação de 0,4 V sugerindo atividade antioxidante. Baseado nos ensaios antioxidante e antifúngico foi possível observar que a presença de grupamentos hidroxilas no C-7 e C-8 do anel cumarínico, assim como a adição de grupamento polar no C-5 favoreceu ambas as atividades antifúngica e antioxidante. Na segunda etapa desse trabalho foi avaliada a citotoxicidade das cumarinas isoladas e algumas cumarinas simples, disponíveis comercialmente, pelo método Metil Tiazol Tetrazólio (MTT) usando linhagens de glioma humano (U138-MG) e de ratos (C6). Foi observado que as 6,7-metilenodioxicumarinas causaram uma significativa redução na viabilidade celular, sugerindo uma influência positiva do grupamento metilenodioxi sobre essa atividade. O composto 5-metóxi-6,7-metilenodioxicumarina foi o mais promissor (IC50= 34,6 μM e IC50= 31,6 μM para C6 e U-138 MG, respectivamente). Como desfecho desse trabalho, pode-se concluir que as cumarinas apresentaram uma atividade inibitória frente ao crescimento celular de linhagens de glioma e um efeito fungicida sobre S. schenckii, resultados estes que corroboram com o uso popular dessas plantas. / Coumarins are promising structures and diverse biological activities have been attributed to these secondary plant metabolites. Studies suggest that the mechanism of antifungal compounds is correlated with antioxidant activity. The reaction of tyrosinase, which produces free radicals, is involved in the process of melanization of the fungus Sporothrix schenckii, the agent of subcutaneous mycosis with the highest incidence in southern Brazil. The inhibition of this enzyme has recently been reported to extract Pterocaulon (Asteraceae) This plant is rich in coumarins and used in traditional medicine in Brazil for topical treatment of fungal infections and in folk medicine of Argentina as anticancer. The aim of this study was to investigate the in vitro antifungal activity and correlation with its antioxidant properties and cytotoxic activities of extracts of some species of Pterocaulon, as well as the isolated coumarins, and 4-methylcoumarin analogs obtained by synthesis. The 6.7-methylenedioxycoumarins were isolated from P. balansae and P. lorentzii, while the 4-methylcoumarins were synthesized via Pechmann reaction using microwave. The antifungal activity against Sporothrix schenckii was performed as indicated in the Manual of Clinical and Laboratory Standards Institute. A study of the electrochemical properties of coumarins was performed by cyclic voltammetry, by the method of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and against peroxyl radicals (ACAP) by fluorometric method. The analysis showed that the antifungal activity of the methanol extracts of Pterocaulon species (P. polystachyum, P. balansae, P. lorentzii, P. lanatum and P. cordobense) were active against the strains of the fungus S. schenckii, being the extract of P. polystachyum the most active, presenting Minimum Inhibitory Concentration (MIC) compressed between 156 and 312 μg/mL. The fractionation of lipophilic extracts of P. balansae and P. lorentzii led to the isolation of three methylenedioxycoumarins. The crystallographic data of 5-methoxy-6,7-methylenedioxycoumarin were deposited at the Cambridge Crystallographic Data Center 779123. The synthetic coumarins were obtained in satisfactory yields (98-30%) and reduced reaction time (5-20 min). The screening of these coumarins against strains of the fungus S. schenckii revealed that the 5-carboxy-6,7-dihydroxy-4-methylcoumarin was the most active compound, presenting MIC of 66 μM and Minimum Fungicidal Concentration of 246 μM. This coumarin showed synergism with Amphotericin B, and its MIC was reduced to 15 μM. The antifungal activity of phenolic compounds could be related to its antioxidant activities. The compound 5-carboxy-6,7-dihydroxy-4-methylcoumarin was again the most active with IC50 value of 17.49 μM, showing the highest capacity to deplete the radicals DPPH and ACAP, moreover present a oxidation potential of 0.4 V suggesting antioxidant activity. Based on the antioxidant and antifungal tests it was observed that the presence of hydroxyl groups at C-7 and C-8 of the coumarin ring and the addition of polar grouping at C-5 favored both antifungal and antioxidant activities.In the second part of this work, it was evaluated the cytotoxicity of the Pterocaulon compounds and some commercially available coumarins, with simple structure. The cytotoxic potential was determined by Methyl Thiazole Tetrazolium (MTT) test using strains of human glioma (U138-MG) and rat (C6). It was observed that the 6,7-methylenedioxycoumarins caused a significant reduction in cell viability, suggesting a positive influence of the methylenedioxy group in this activity. The compound 5-methoxy-6,7-methylenedioxycoumarin was the most promising (IC50 = 34.6 μM and IC50 = 31.6 μM for C6 and U-138 MG, respectively). In conclusion, this work it was demonstrated that some coumarins showed an inhibitory activity against the growth of glioma cell lines and a fungicidal effect on the S. schenckii. These results corroborate the popular use of these plants.

M.Ed. / Environmental Education fieldwork is any educational activity that takes place outside the classroom. It may take place on the school grounds or in a local park, or in fact anywhere where practical outdoor classroom activities are possible. As such Environmental Education fieldwork is regarded by most Environmental Education teachers as central to teaching and learning activities, because of its nature in engaging learners through direct experiences in the environment. Therefore, this cannot happen in rigidly planned classroom activities where the teacher and the text book are the only source of information. Teaching and learning methods employed in Environmental Education fieldwork involves learners in diverse encounter, dialogue and foster greater awareness and meaningful change in learner’s insight and attitudes towards the environment. This study investigates the implementation of active learning within Environmental Education fieldwork in primary schools. Literature review on active learning, fieldwork and Environmental Education and the curriculum was undertaken to establish the extent to which active learning within fieldwork in Environmental Education is implemented in primary schools. One hundred questionnaires were distributed to primary school teachers to complete. Interviews were conducted with held with teachers and focus group interviews were also conducted with learners from primary school in the Nongoma district. The main findings of the study were the following: • The major finding of this study was that teachers were not knowledgeable about the implementation of active learning within fieldwork in Environmental Education. Problems identified as hindrances to the undertaking of Environmental Education fieldwork clearly shows that very few if any of the teachers undertook Environmental Education fieldwork in their learning programmes. • The need to state clear objectives for the undertaking of Environmental Education fieldwork became evident in this study. Clear objectives determine meaningful learning tasks for the learners to engage in during the undertaking of Environmental Education fieldwork. Teachers failed to develop meaningful learning activities that are pertinent to Environmental Education fieldwork. • The study further revealed that teachers had very little knowledge of the procedures for the undertaking of Environmental Education fieldwork. From this study it is evident that active participatory learning within Environmental Education fieldwork was not implemented effectively in primary schools.

No description available.

The purpose of this study was to further clarify the relationship between couple leisure patterns and marital satisfaction by examining the contribution of joint couple leisure involvement, leisure time, and leisure satisfaction to couples' satisfaction with married life. The sample consisted of 48 married couples (N = 96). The Marital Activity Profile (MAP), a modified version of the Family Leisure Activity Profile (FLAP) was used to determine couple leisure involvement in core and balance leisure activities and leisure satisfaction. The Satisfaction With Married Life (SWML), a modified version of the Satisfaction With Life Scale (SWLS) was used to measure marital satisfaction. Blocked multiple regression analyses indicated a positive relationship between satisfaction with couple leisure and marital satisfaction, specifically satisfaction with core leisure activity patterns. Implications and recommendations for further research are discussed.

No / A library of 53 benzimidazole derivatives, with substituents at positions 1, 2 and 5, were synthesized and screened against a series of reference strains of bacteria and fungi of medical relevance. The SAR analyses of the most promising results showed that the antimicrobial activity of the compounds depended on the substituents attached to the bicyclic heterocycle. In particular, some compounds displayed antibacterial activity against two methicillin-resistant Staphylococcus aureus (MRSA) strains with minimum inhibitory concentrations (MICs) comparable to the widely-used drug ciprofloxacin. The compounds have some common features; three possess 5-halo substituents; two are derivatives of (S)-2-ethanaminebenzimidazole; and the others are derivatives of one 2-(chloromethyl)-1H-benzo[d]imidazole and (1H-benzo[d]imidazol-2-yl)methanethiol. The results from the antifungal screening were also very interesting: 23 compounds exhibited potent fungicidal activity against the selected fungal strains. They displayed equivalent or greater potency in their MIC values than amphotericin B. The 5-halobenzimidazole derivatives could be considered promising broad-spectrum antimicrobial candidates that deserve further study for potential therapeutic applications.

Published Article / Adolescent and young adult university students' decreasing physical activity levels impact considerably on their psychological stress levels. Acute and long-term bouts of exercise can reduce psychological stress (Taylor, 2000). In this study, the Leisure-time Exercise Questionnaire and the Positive Affect Negative Affect Scale were used to determine students' physical activity levels and emotional states before their first and second test weeks, in order to ascertain the effect of therapeutic recreational activities on their appraisals of their feelings and emotions during academically demanding times. The recreational therapy was presented between these test weeks. Results indicated that both the physical activity levels and the emotional state of the experimental group improved. Future studies could include determining which recreation activity has the greatest therapeutic effect while better controlling participants in both groups. In view of its potential value for relieving stress, therapeutic recreation could be used as a technique in relieving stress prior to tests and examinations.

ABSTRACT THE EFFECTS OF HIV DISEASE AND LIFESTYLE FACTORS ON CELLULAR AGING IN TRANSGENDER WOMEN by Scott Stephen Sohn Background: Telomeres are short tandem repeats of nucleotides at the ends of chromosomes. These specialized structures serve as caps on the end of the chromosomes, which protect DNA integrity. Telomeres get shorter each time a cell replicates, but the DNA remains intact as long as the telomere caps are a sufficient length. In time, telomeres become too short to protect DNA, which leads to cellular death. Previous research has shown that disease and negative lifestyle factors play a role in accelerated telomere attrition throughout the cellular life cycle. Objective: The purpose of this study was to determine if HIV infection and lifestyle factors in a transgender population living in Atlanta Georgia are associated with telomere length reduction. Participants/setting: This study is a secondary analysis of data provided by a Georgia State University study entitled “Telomere Length, Environmental Stressors and Health Related Outcomes among Transgender Women”. The study included 92 transgender women from Atlanta, Georgia with 49 reporting HIV infection. Two sources of data were collected, survey responses collected during face to face interviews and a saliva sample for DNA analysis. Statistical analysis: Frequency statistics were used to describe the sample population. A Mann Whitney U was used to evaluate telomere length using the T/S ratio by HIV status, by physical activity level (healthy active or low active) and by fruit and vegetable intake category (Don’t eat, 1-2 servings/day, 3-4 servings/day vs. >5 servings/day) in the total Population. Multiple regression analysis was used to examine the association between independent variables (activity level, body mass index, fruit and vegetable intake, hormone use, race, HIV status and age) and telomere length. Results: The majority of the population was Black (84%) with a median age of 33 years (range, 18 to 65 years). No significant association was observed between HIV infection and T/S ratio. The vast majority of the population reported low activity level and only 9% reported consuming >5 servings of fruits and vegetables daily. No significant association was found between fruit and vegetable intake or physical activity level and T/S ratio in this population. Conclusion: HIV infection, Fruit and vegetable intake, and physical activity were not found to impact telomere length in an urban population of transgender women. Future research is needed to further understand the mechanisms that impact telomere length throughout the cellular life cycle within the transgender population.