92 research outputs found

    A utilização de geotecnologias no ensino da Geografia para alunos do ensino fundamental

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    Orientador : Marcos Aurélio Tarlombani da SilveiraMonografia (especialização) - Universidade Federal do Paraná, Setor de Ciências da Terra, Curso de Especialização em Análise AmbientalInclui referências : p. 1

    Teorema de Noether do c√°lculo das varia√ß√Ķes e controlo √≥ptimo estoc√°sticos

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    Mestrado em Matem√°tica Aplicada √† EngenhariaNeste trabalho come√ßamos por apresentar os problemas cl√°ssicos do c√°lculo das varia√ß√Ķes e controlo √≥ptimo determin√≠sticos, dando √™nfase √°s condi√ß√Ķes necess√°rias de optimalidade de Euler-Lagrange e Princ√≠pio do M√°ximo de Pontryagin (Cap√≠tulo 1). No Cap√≠tulo 2 demonstramos o Teorema de Noether do c√°lculo das varia√ß√Ķes e uma sua extens√£o ao controlo √≥ptimo. Como exemplos de aplica√ß√£o mencionamos as leis de conserva√ß√£o de momento e energia da mec√Ęnica, v√°lidas ao longo das extremais de Euler-Lagrange ou das extremais de Pontryagin. Numa segunda parte do trabalho introduzimos o c√°lculo das varia√ß√Ķes estoc√°stico (Cap√≠tulo 3) e demonstramos um teorema de Noether estoc√°stico obtido recententemente por Jacky Cresson (Cap√≠tulo 4). O Cap√≠tulo 5 √© dedicado √° programa√ß√£o din√Ęmica: caso discreto e cont√≠nuo, caso determin√≠stico e estoc√°stico.In this master thesis we begin by presenting the classical deterministic problems of the calculus of variations and optimal control, with emphasis to the necessary optimality conditions of Euler-Lagrange and Pontryagin‚Äôs Maximum Principle (Chapter 1). In Chapter 2 we prove the Noether‚Äôs theorem of calculus of variations and an extension to optimal control. As examples of application we mention the conservation laws of momentum and energy, valid along the Euler-Lagrange or Pontryagin extremals. In the second part of the thesis we introduce the stochastic calculus of variations (Chapter 3) and we prove a recent stochastic Noether-type theorem obtained by Jacky Cresson (Chapter 4). The Chapter 5 is dedicated to dynamic programming: discrete-time and continuous cases, both deterministic and stochastic


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    Euphorbia tirucalli, a plant commonly known as aveloz, has been employed in anticancer therapy with little scientific proof. The goal of this study was to evaluate the cytotoxic potential and expression of¬†caspase-3¬†and p53 in colorectal cancer cell lines treated with aveloz extracts. Hexanic and hydroalcoholic extracts were prepared in different concentrations. After 96 h, cell viability and apoptosis rate (p53 and caspase-3 expression) were verified. The hexanic extract revealed higher cytotoxicity on HCT-116 cell line at concentrations above 125 ¬Ķg/mL, and hydroalcoholic extract above 500 ¬Ķg/mL. LC50 for the hexanic extract was 60.2873 ¬Ķg/mL, and for hydroalcoholic extract 100.6066 ¬Ķg/mL. There were significant differences among the averages of cells marked with p53 at the concentrations 62.5, 250 and 500 ¬Ķg/mL, as well as among the averages of caspase-3-positive cells at the concentrations 62.5, 125 and 500 ¬Ķg/mL, with higher cytotoxic effect being observed for the hydroalcoholic extract. The obtained data provides evidence for the cytotoxic potential in vitro of the hydroalcoholic and hexanic extracts of aveloz on HCT-116 cell line. There was an increase in the expression of caspase-3 and p53 in the tumor line cells exposed to extracts of E. tirucalli

    Assessment of the total organic carbon and conductivity in consecutive dyeings with reactive dyestuffs using treated effluent by UV/H2O2 photocatalysis

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    The paper was monitored the conductivity (g¬∑L-1 of NaCl), the absorbances values (Abs) and the amount of TOC (total organic carbon), before and after five consecutive dyeings made with reuse water, obtained from treated effluent by UV/H2O2 photocatalysis. All rates of decolorization were above 92%, the removal of total organic carbon was above 89% in all treatments and the economy of NaCl was from 3.10 in the first recipe, 3.17 in the second, 3.49 in the third, 3.79 in the fourth and 4.05 in the fifth recipe. The five dyeings compared with same dyeings made with deionized water presented a color deviation (őĒE*) below 1. The conventional dyeings would consume 80 L/kg against 40 L/kg used in the dyeing process proposed in this study, representing a great economy of water, with no discharge of effluents142139144sem informa√ß√£osem informa√ß√£

    Updates on malaria epidemiology and profile in Cabo Verde from 2010 to 2019: the goal of elimination.

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    BACKGROUND: Located in West Africa, Cabo Verde is an archipelago consisting of nine inhabited islands. Malaria has been endemic since the settlement of the islands during the sixteenth century and is poised to achieve malaria elimination in January 2021. The aim of this research is to characterize the trends in malaria cases from 2010 to 2019 in Cabo Verde as the country transitions from endemic transmission to elimination and prevention of reintroduction phases. METHODS: All confirmed malaria cases reported to the Ministry of Health between 2010 and 2019 were extracted from the passive malaria surveillance system. Individual-level data available included age, gender, municipality of residence, and the self-reported countries visited if travelled within the past 30¬†days, therby classified as imported. Trends in reported cases were visualized and multivariable logistic regression used to assess risk factors associated with a malaria case being imported and differences over time. RESULTS: A total of 814 incident malaria cases were reported in the country between 2010 and 2019, the majority of which were Plasmodium falciparum. Overall, prior to 2017, when the epidemic occurred, 58.1% (95% CI 53.6-64.6) of infections were classified as imported, whereas during the post-epidemic period, 93.3% (95% CI 86.9-99.7) were imported. The last locally acquired case was reported in January 2018. Imported malaria cases were more likely to be 25-40¬†years old (AOR: 15.1, 95% CI 5.9-39.2) compared to those under 15¬†years of age and more likely during the post-epidemic period (AOR: 56.1; 95% CI 13.9-225.5) and most likely to be reported on Sao Vicente Island (AOR‚ÄČ=‚ÄČ4256.9, 95% CI‚ÄČ=‚ÄČ260-6.9e+4) compared to Boavista. CONCLUSIONS: Cabo Verde has made substantial gains in reducing malaria burden in the country over the past decade and are poised to achieve elimination in 2021. However, the high mobility between the islands and continental Africa, where malaria is still highly endemic, means there is a constant risk of malaria reintroduction. Characterization of imported cases provides useful insight for programme and enables better evidence-based decision-making to ensure malaria elimination can be sustained

    Perfil de Uso do Espaço Virtual como Estratégia Pedagógica para a Práxis Educativa Online

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    In this article we analyze the of students usage styles of the virtual environment as a pedagogical strategy for online educational praxis. Based on the learning styles theory, the theoretical approach of the usage styles of virtual space presupposes 4 (four) basic styles, namely: 1) participatory; 2) search and research; 3) structuring and planning and 4) concrete action and production. The article is configured as an experience report, carried out with a questionnaire application with 159 students from a postgraduate distance education course. Data revealed a predominance of structure and planning style on the virtual environment (40.7%), with balanced results in search and research style (36.4%), participatory use (36.4%) and concrete action production (34.9%). Thus, the faculty was oriented to prioritize pedagogical strategies able to sequence learning, starting from the predominant style and advancing by the others. The report concludes by pointing out the pertinence of the diagnosis of the virtual environment usage styles for the online educational praxis, recommending its implementation in the beginning of the academic term, aiming to guide the teaching work and elaboration of didactic activities. Keywords: Virtual environment usage styles. Pedagogical strategies.Neste artigo analisamos o perfil de uso do espa√ßo virtual dos estudantes como estrat√©gia pedag√≥gica para a pr√°xis educativa nos ambientes virtuais de aprendizagem. Decorrente da teoria dos estilos de aprendizagem, a abordagem te√≥rica do perfil de uso do espa√ßo virtual pressup√Ķe quatro estilos b√°sicos: 1) participativo; 2) de busca e pesquisa; 3) de estrutura√ß√£o e planejamento; e 4) de a√ß√£o concreta e produ√ß√£o. O estudo configura-se como um relato de experi√™ncia, realizado com a aplica√ß√£o do question√°rio de identifica√ß√£o desse perfil com 159 estudantes em um curso de p√≥s-gradua√ß√£o lato sensu a dist√Ęncia. Os dados revelaram predom√≠nio do estilo de estrutura√ß√£o e planejamento no espa√ßo virtual (40,7%), com resultados equilibrados nos estilos de busca e pesquisa (36,4%), uso participativo (36,4%) e de a√ß√£o concreta e de produ√ß√£o (34,9%). Diante disso, os docentes do curso foram orientados a priorizar estrat√©gias pedag√≥gicas capazes de sequenciar a aprendizagem, partindo do estilo predominante e avan√ßando pelos demais estilos menos desenvolvidos. O relato conclui apontando a pertin√™ncia do diagn√≥stico dos estilos de uso do espa√ßo virtual para a pr√°xis educativa online, recomendando a sua realiza√ß√£o no in√≠cio do per√≠odo letivo, visando nortear o trabalho docente e elabora√ß√£o das atividades did√°ticas. Palavras-chave: Estilos de uso do espa√ßo virtual. Estrat√©gias pedag√≥gicas

    Estudo histol√≥gico e histoqu√≠mico da elastose solar em les√Ķes de queilite act√≠nica

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    The actinic cheilitis (AC) is a diffuse lesion of the vermillion of the lower lip, due to excessive exposure of the lips to the ultraviolet radiation. It may show histomorphologic alterations indicative of the abnormal differentiation. Histopathologically, the main characteristic of the skin photoaged is the accumulation of the basophilic material, amorphous, rich in elastic fibers, referred to as solar elastosis. This aspect is demonstrated by the AC; however, the most of the researchers do not investigate lesions provoked by actinic damages like AC. The objective is to investigate the degree of dysplasic and the pattern of organization of collagens and elastics fibers of this lesion. Using H&E, Picrossirius and orcein of Weigert, respectively the lesions were studied.¬† The most of the patients were males situated in the fifth decade of life. Histopathologically, six cases showed discrete dysplasia, four moderate dysplasia and three intense dysplasia. In the extracellular matrix was observed absent collagen fibers in the areas corresponding to the solar elastosis.¬† In these areas, they were substituted by elastic fibers originating probably a substance similar to elastin. This material is present in actinic cheilitis. Like extracellular matrix exert action on mechanism of cellular migration and invasion, this study is important to understand the participation of these components because actinic cheilitis may exhibit malignant alteration.¬†¬†A queilite act√≠nica (QA) apresenta-se como uma les√£o difusa do vermelh√£o do l√°bio inferior, resultante da exposi√ß√£o √† radia√ß√£o solar excessiva, podendo exibir altera√ß√Ķes histomorfol√≥gicas indicativas de desvios da diferencia√ß√£o normal. Histologicamente, a caracter√≠stica principal da pele que exibe fotoenvelhecimento √© o ac√ļmulo do material basof√≠lico, amorfo, rico em fibras el√°sticas, denominada elastose solar. Esse aspecto √© demonstrado pelas les√Ķes de QA, no entanto, a maioria dos pesquisadores estuda o tecido conjuntivo da pele normal e (ou) exposta, deixando de lado as les√Ķes labiais provocadas por danos act√≠nicos, como √© o caso da QA. O objetivo deste trabalho √© estudar o grau de displasia e o padr√£o de organiza√ß√£o das fibras col√°genas e el√°sticas nas les√Ķes de queilite act√≠nica. Atrav√©s das t√©cnicas de rotina, Picrossirius e orce√≠na de Weigert foram estudados respectivamente, o grau de displasia e o padr√£o de organiza√ß√£o das fibras col√°genas e el√°sticas dessa les√£o. Dos aspectos cl√≠nicos, evidenciou-se uma maior freq√ľ√™ncia das les√Ķes de QA no sexo masculino, e a faixa et√°ria atingiu predominantemente a quinta d√©cada de vida. Histopatologicamente, seis casos exibiram displasia discreta, quatro exibiram displasia moderada e tr√™s, displasia intensa. Na matriz extracelular, foi observada a aus√™ncia de fibras col√°genas nas √°reas correspondentes √† elastose solar. Nessas √°reas, as fibras col√°genas foram substitu√≠das por fibras el√°sticas, provavelmente dando origem ao ac√ļmulo de material semelhante √† elastina, caracter√≠stica das les√Ķes de queilite act√≠nica. Tendo em vista que a matriz extracelular pode influenciar os processos de invas√£o e migra√ß√£o celulares, a participa√ß√£o desses componentes torna-se importante, uma vez que a queilite act√≠nica √© pass√≠vel de transforma√ß√£o maligna

    Shade and Altitude Implications on the Physical and Chemical Attributes of Green Coffee Beans from Gorongosa Mountain, Mozambique

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    Coffea arabica L. is as a tropical crop that can be grown under monocrop or agroforestry (AFS) systems, usually at altitudes greater than 600 m, with suitable environmental conditions to bean quality. This study aimed to assess the effect of altitude (650, 825, and 935 m) and light conditions (deep shade‚ÄĒDS, and moderate shade‚ÄĒMS provided by native trees, and full Sun‚ÄĒFS) on the physical and chemical attributes of green coffee beans produced in the Gorongosa Mountain. Regardless of altitude, light conditions (mainly MS and FS) scarcely affected most of the studied physical and chemical attributes. Among the few exceptions in physical attributes, bean mass tended to lower values under FS in all three altitudes, whereas bean density increased under FS at 650 m. As regards the chemical compound contents, sporadic changes were found. The rises in trigonelline (MS and FS at 935 m), soluble sugars (FS at 935 m), and the decline in p-coumaric acid (MS and FS at 825 m), may indicate an improved sensory profile, but the rise in FQAs (FS at 825 m) could have a negative impact. These results highlight a relevant uncertainty of the quality changes of the obtained bean. Altitude (from 650 to 935 m) extended the fruit maturation period by four weeks, and altered a larger number of bean attributes. Among physical traits, the average sieve (consistent tendency), bean commercial homogeneity, mass, and density increased at 935 m, whereas the bean became less yellowish and brighter at 825 and 935 m (b*, C* colour attributes), pointing to good bean trade quality, usually as compared with beans from 650 m. Furthermore, at 935 m trigonelline and 5-CQA (MS and FS) increased, whereas FQAs and diCQAs isomers declined (in all light conditions). Altogether, these changes likely contributed to improve the sensory cup quality. Caffeine and p-coumaric acid showed mostly inconsistent variations. Overall, light conditions (FS, MS, or DS) did not greatly and consistently altered bean physical and chemical attributes, whereas altitude (likely associated with lower temperature, greater water availability (rainfall/fog), and extended maturation period) was a major driver for bean changes and improved qualityinfo:eu-repo/semantics/publishedVersio
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