813 research outputs found

    Extracellular enolase of Candida albicans is involved in colonization of mammalian intestinal epithelium

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    Enolase is secreted by C. albicans and is present in its biofilms although its extracellular function is unknown. Here we show that extracellular enolase mediates the colonization of small intestine mucosa by C. albicans. Assays using intestinal mucosa disks show that C. albicans adhesion is inhibited, in a dose dependent mode, either by pretreatment of intestinal epithelium mucosa disks with recombinant C. albicans enolase (70% at 0.5 mg/ml enolase) or by pretreatment of C. albicans yeasts with anti-enolase antibodies (48% with 20 µg antiserum). Also using flow cytometry, immunoblots of conditioned media and confocal microscopy we demonstrate that enolase is present in biofilms and that the extracellular enolase is not an artifact due to cell lysis, but must represent functional secretion of a stable form. This is the first direct evidence that C. albicans extracellular enolase mediates colonization on its primary translocation site. Also, because enolase is encoded by a single locus in C. albicans, its dual role peptide, as glycolytic enzyme and extracellular peptide, is a remarkable example of gene sharing in fungi

    Comparação da fauna de formigas de serapilheira entre área de floresta atlântica secundária e plantação adjacente de pinus no sudeste do Brasil

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    We investigated the influence of Pinus afforestation on the structure of leaf-litter ant communities in the southeastern Brazilian Atlantic Forest, studying an old secondary forest and a nearly 30 year-old never managed Pinus elliottii reforested area. A total of 12,826 individual ants distributed among 95 species and 32 genera were obtained from 50 1 m² samples/ habitat. Of these, 60 species were recorded in the pine plantation and 82 in the area of Atlantic forest; almost 50% of the species found in the secondary forest area were also present in the pine plantation. The number of species per sample was significantly higher in the secondary forest than in the pine plantation. Forest-adapted taxa are the most responsible for ant species richness differences between areas, and the pine plantation is richer in species classified as soil or litter omnivorous-dominants. The specialized ant predators registered in the pine plantation, as seven Dacetini, two Basiceros, two Attini and two Discothyrea, belong to widely distributed species. The NMDS (non-metric multidimensional scaling) ordination also suggested strong differences in similarity among samples of the two areas. Furthermore, this analysis indicated higher sample heterogeneity in the secondary forest, with two clusters of species, while in the pine plantation the species belong to a single cluster. We applied the ant mosaic hypothesis to explain the distribution of the leaf-litter fauna and spatial autocorrelation tests among samples. We argue that the results are likely related to differences in quality and distribution of the leaf-litter between the pine plantation and the secondary area.A influência do reflorestamento com Pinus na estrutura da fauna de formigas de serapilheira foi investigada, estudando uma floresta Atlântica secundária inalterada há 30 anos e uma área reflorestada com Pinus elliottii no Sudeste do Brasil. Em 50 amostras de 1 m² tomadas em cada área, foram coletados 12.826 indivíduos, distribuídos em 95 espécies e 32 gêneros de formigas. Foram identificadas 60 espécies na área reflorestada com Pinus e 82 espécies na área de floresta secundária; aproximadamente 50% das espécies foram registradas nas duas áreas. A mediana do número de espécies por amostra foi maior na floresta secundária. Táxons com biologia especializada são responsáveis por grande parte das diferenças de composição de fauna, sendo a área de reflorestamento com Pinus mais rica em espécies onívoras e dominantes. Predadoras especializadas registradas na área de Pinus, como sete espécies de Dacetini, duas Basiceros, duas Attini e duas Discothyrea, têm ampla distribuição na Floresta Atlântica. A ordenação das amostras com o escalonamento multidimensional não-métrico (NMDS) indicou grande diferença na similaridade entre as amostras das áreas. Adicionalmente, essa análise sugere maior heterogeneidade na composição das amostras da floresta secundária, identificando dois agrupamentos de espécies, enquanto a área de Pinus apresenta um agrupamento apenas. Para investigar quais fatores podem explicar a heterogeneidade observada, testes de co-ocorrência e de autocorrelação espacial foram aplicados entre amostras de cada área. Nossa conclusão é que as diferenças observadas devem estar relacionadas com diferenças na qualidade e distribuição da serapilheira entre as áreas.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)UMC - Fundação de Amparo ao Ensino e Pesquis

    Perspectives of PV Microgeneration in Brazil: A Proposition of Regulation Enhancement Methodology

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    The solar photovoltaic (PV) generation is disseminating on multiple kinds of sites due to the energy market liberalization, the renewable energy sources subsidies policy, the decreasing of acquisition costs and the adaptability to different installation conditions. These factors allowed the growth of PV generation, especially in the distributed generation (DG) segment. Meanwhile, the development of a legal and regulatory apparatus became mandatory to assure benefits to DG-adopters, without causing damages to the utility grid, preventing technical failures and eventual excessive pricing to non-adopters. As the technology innovations impose new possibilities and the number of adopters grows exponentially, the challenges become more visible and a regulation update, urgent. In this context, this paper aims to review the current pricing model for DG in Brazil, focusing on PV microgeneration, and to propose a methodology based on the Delphi Method to enhance the most critical topics of the on-going regulation

    Design and construction of a didactic standalone photovoltaic plant

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    This paper proposes the design and construction of a standalone didactic photovoltaic (PV) plant. The system components are available as a didactic kit to the students of the Federal Institute of Education, Science and Technology of Ceará (IFCE), Brazil. Thus, contributing to the teaching-learning process and providing a system to be used in future researches. In addition, the system was designed for supplying electricity to the lighting circuit of the Energy Processing Laboratory, located at IFCE Fortaleza Campus. The PV system developed during the work has an autonomy of 900 Ah and the total installed power of 840 Wp. Using a data capture system, a generation generated by the PV microgeneration was registered in operation up to 647 W

    Embedded System for Real Color Composition in Experimental Physics

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    Software can be considered educational when properly contextualized in a relationship of teaching and learning. This paper describes an embedded system and an educational software developed and applied in experimental physics to real and virtual colors composition. The educational system developed allows student interaction by voice commands, which makes the assimilation process of red/green/blue (RGB) color formation concepts more didactic and playful. The application of educational software in experiments also allows to verify, in real time, the influence of programs change on the physical phenomena and stimulates the logical reasoning development and consequently the autonomy of the students, to the measure that can raise hypothesis, make modifications in the programming and take off conclusions from the practical results obtained

    Quantification and distribution of vibrio species in water from an estuary in Ceará-Brazil impacted by shrimp farming

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    Vibrios were quantified and their distribution determined for the estuary of the Coreaú river, in Northeastern Brazil, based on 24 water samples collected between June and October 2005. The most probable number of vibrios per 100 mL ranged from 230 x 10³ to 240 x 10(11). The pH value was the environmental factor most strongly associated with the abundance of vibrios. Sixty-two vibrio strains were isolated belonging to 15 species (6 of which observed in June-September and 8 in October). The most frequently isolated species were V. parahaemolyticus and V. cholerae.Foram realizadas análises concernentes à quantificação e distribuição de Vibrio em 24 amostras de água do estuário do Rio Coreaú (CE) no período de junho a novembro de 2005. O Número Mais Provável (NMP/100 mL) de Vibrio oscilou de 230 x 10³ a 240 x 10(11). O pH foi o fator ambiental que mais favoreceu ao aumento da microbiota de Vibrio. Foram isoladas 62 cepas de Vibrio, sendo observada uma distribuição de sete espécies nos meses de junho a setembro, e oito espécies no mês de outubro. As espécies mais freqüentes nos isolamentos foram V. parahaemolyticus e V. cholerae

    Chemical Composition and In Vitro Cytotoxic and Antimicrobial Activities of the Essential Oil from Leaves of Zanthoxylum monogynum St. Hill (Rutaceae).

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    Background: The Zanthoxylum monogynum species belongs to the family Rutaceae and is found in Southeast, Midwest, and Northeast Brazil. For this genus several biological activities have been described. Methods: The essential oil (EO) was obtained from the leaves of Zanthoxylum monogynum by hydro-distillation and was analyzed by gas chromatograph and gas chromatograph/mass spectrometry (GC and GC/MS). Also the EO of Z. monogynum was evaluated for in vitro cytotoxic activity against six tumor cell lines and for antimicrobial activity, performing disk diffusion and MIC assays with yeast and bacterial strains. Results: The chemical analysis afforded the identification of 18 components (99.0% of the EO). The major components were found to be citronellol (43.0%) and farnesol (32.0%). The in vitro cytotoxic activity against tumor cell lines, resulted in IC50 values ranging from 11-65 µg/mL against all tested cell lines. Antimicrobial activity of the essential oil was also tested and oil was effective, especially against Cryptococcus sp. yeast. All the tested yeast strains showed at least 90% growth inhibition. Conclusions: the essential oil from leaves of Z. monogynum has a different qualitative and quantitative composition when compared to the composition previously described. Also this EO has significant cytotoxic activity and moderate activity against Cryptococcus sp. and Saccharomyces cereviseae yeasts

    Production of xylooligosaccharides from Brazilian Syrah grape pomace flour

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    BACKGROUND: The aim of this work was to determine the most favorable conditions for the production of xylooligosaccharides (XOS) from Brazilian Syrah grape pomace. Chemical processes were performed using a rotatable central composite design, where the concentration of sulfuric acid or concentration of sodium hydroxide and grape pomace flour: solvent mass ratio were the dependent variables. Enzymatic production was also evaluated using xylanase produced by Aspergillus niger 3T5B8 and Viscozyme® enzymatic commercial cocktail. RESULTS: Chemical extraction allowed to recover 21.8 to 74.6% and 5.2 to 96.3% of total XOS for acid and alkaline processes, respectively. Enzymatic production using xylanase extracted up to 88.68 ± 0.12% of total XOS and up to 84.09 ± 2.40% with Viscozyme®. CONCLUSION: The present study demonstrated different feasible methods to produce high added value molecules, the xylooligosaccharides, from Syrah grape pomace flour, valorizing this major by‐product. The use of enzymatic cocktails demonstrated to be an alternative to the conventional methods, allowing to obtain an eco‐friendly and sustainable grape pomace extract.info:eu-repo/semantics/acceptedVersio

    Evaluation of quality of life of gymnastics practitioners

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    Introdução: A qualidade de vida (QV) de trabalhadores vem sendo alvo de pesquisas há algum tempo no Brasil. Sendo assim verifica-se a necessidade de avaliar QV e parâmetros antropométricos de participantes, funcionários e estagiários, de instituição de ensino que realizaram a prática da ginástica laboral com o objetivo de melhorar sua rotina diária de trabalho. Material e Métodos: Foi realizada ginástica laboral para os participantes e a versão brasileira do questionário SF-36 foi aplicada, além disto, foram avaliados peso e altura e calculado o índice de massa corporal (IMC). Resultados: Foram avaliados 21 indivíduos, sendo 19% masculinos e 81% femininos, com idade média de 35,47±12,90 anos. A amostra tinha média de peso de 63,26±5,80 gramas e média de 1,64±3,90 centímetros de altura e foi calculado o IMC, e obteve-se média de 23,25±2,90. Os aspectos motores, emocionais, além dos sociais e mentais têm determinantes no aspecto que influenciam a QV dos praticantes demonstrando que a realização de tal atividade, mesmo que em um período curto (três meses) parece trazer influências benéficas no cotidiano do praticante de tal atividade, pois a maioria dos entrevistados relatam boa saúde física e emocional, e sem prejuízos de suas atividades laborais. Conclusões: Os participantes estão satisfeitos e motivados com a liberdade de expressão, participações em decisões e satisfação com a QV no trabalho, sendo assim com o conhecimento do grau de satisfação dos trabalhadores, instituições podem ajuda a direcionar estratégias de prevenção, orientação e suporte dos seus trabalhadores, afim de proporcionar um ambiente saudável de trabalho. Observou-se que a prática de ginástica laboral contribui para estes resultadosIntroduction: Quality of life (QOL) of workers has been the subject of research for some time in Brazil. Therefore, there is the need to assess QOL and anthropometric parameters of participants, employees and trainees, teaching institution that carried out the practice of gymnastics in order to improve their daily work routine. Methods: gymnastics was held for the participants and the Brazilian version of the SF-36 questionnaire was applied were assessed height and weight and calculated body mass index (BMI). Results: A total of 21 subjects, 19% male and 81% female, mean age 35.47 ± 12.90 years. The sample had an average weight of 63.26 ± 5.80 grams and average of 1.64 ± 3.90 cm in height and calculated BMI, and obtained an average of 23.25 ± 2.90. The engines, emotional aspects, as well as social and mental are determinants in the aspect that influence QOL of practitioners demonstrating that the performance of such activity, even in a short period (three months) seems to bring beneficial influences on practicing everyday in such activity because the majority of respondents reported good physical and emotional health, and without prejudice to their work activities. Conclusions: Participants are satisfied and motivated with freedom of expression, participation in decisions and satisfaction with QOL at work, so with knowledge of the degree of employee satisfaction, institutions can help to direct prevention strategies, guidance and support of its employees in order to provide a healthy working environment. It was found that practicing gymnastics contributes to these result
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