402 research outputs found

    High occurrence of Flavescence dorée phytoplasma early in the season on grapevines infected with grapevine yellows

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    Research NoteA survey for the presence of phytoplasmas associated with grapevine yellows in about 500 Italian vineyards was conducted from 1999 to 2004. Grapevines with the earliest symptoms were mostly infected with Flavescence dorée type C phytoplasma (FD-C). As the season advanced, a steady relative decrease in the occurrence of FD-C coincided with a clear relative increase in Bois noir phytoplasma. The relative occurrence of Flavescence dorée type D phytoplasma remained stable.

    Avaliação da qualidade físico-química e microbiológica de sete marcas de leite padronizados produzidas nos Estados de Goiás e Minas Gerais e comercializadas no Distrito Federal.

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    Resumo: O leite é um produto rico em proteínas, carboidratos e vitaminas, sendo um alimento de alto valor nutricional. Pela sua composição físico-química, é um meio propício ao desenvolvimento de micro-organismos. A obtenção, o beneficiamento e o armazenamento devem ser feitos de maneira higiênica para garantir a qualidade final do produto. Os objetivos deste trabalho foram avaliar a qualidade físico-química e microbiológica de sete marcas de leites padronizados comercializadas no Distrito Federal. As amostras foram oriundas de sete laticínios, cinco do Estado de Goiás, e duas de Minas Gerais. As análises foram realizadas no Laboratório de Análise de Alimentos da Universidade de Brasília seguindo normas do Instituto Adolfo Lutz. Os resultados foram comparados aos limites estabelecidos pela Instrução Normativa n°51 e revelam qualidade satisfatória para os parâmetros físico-químicos para as setes marcas. Entretanto, as análises qualitativas de eficiência da pasteurização e microbiológica indicam leites impróprios para o consumo humano. Não foi detectada presença de antibióticos nas marcas. [Evaluation of physico-chemical and microbiological of seven brands of standardized milk produced in the states of Goiás and Minas Gerais and marketed in the Federal District]. Abstract: Milk is a product rich in protein, carbohydrates and vitamins being a food of high nutritional value. By its physico-chemical composition is a propitious means to the development of microorganisms. Obtaining, processing and storage shall be made in a hygienic manner to ensure the quality of the final product. The aims of this study were to evaluate the physico-chemical and microbiological characteristics of the seven brands of standardized milks marketed in the Federal District. The samples were from seven dairy, five State of Goiás and two of Minas Gerais. The analyzes were performed at the Laboratory of Food Analysis, University of Brasilia, following rules of the Institute Adolfo Lutz. The results were compared to the limits established by Normative Instruction No. 51 and show satisfactory quality for physico-chemical parameters for the seven brands. However, qualitative analysis of efficiency of pasteurization and microbiological indicate milks unfit for human consumption. Antibiotics were not detected in all marks

    Avaliação qualitativa e quantitativa de leite Tipo A comercializados no Distrito Federal.

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    Resumo: O leite tipo A é processado em granjas leiteiras. Possui maior valor agregado e menor carga microbiológica. O objetivo desse trabalho foi avaliar a qualidade do produto comercializado no Distrito Federal. Foram avaliadas duas marcas durante quatro meses. As amostras foram avaliadas em testes de fraude e foram feitas análise físico-química. Ambas as marcas apresentaram índice crioscópico em desacordo com a legislação vigente e presença de sacarose. Esse resultado evidencia a fraude para aumentar o rendimento do produto. Além disso, a marca B apresentou bicarbonato em sua composição e teste de peroxidase negativa em 14,3% das amostras. Esses resultados mostram que a marca B fraudou o leite na tentativa de reduzir a carga microbiana. [Qualitative and Quantitative Evaluation of type A milk marketed in the Federal District]. Abstract: The type A milk is processed into dairy farms. Has a higher value and lower microbiological load. The aim of this study was to evaluate the quality of the product marketed in the Federal District. We evaluated two brands during four months. The samples were evaluated in tests of fraud and physicochemical analysis. Both brands had cryoscopic index in disagreement with current legislation and presence of sucrose. This result evidences the fraud to increase product yield. In addition, the type B showed bicarbonate in their composition and peroxidase negative test in 14,3% of samples. These results show that type B defrauded milk in attempt to reduce the microbial load

    Toward Visualization-Specific Heuristic Evaluation

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    This position paper describes heuristic evaluation as it relates to visualization and visual analytics. We review heuristic evaluation in general, then comment on previous process-based, performance-based, and framework-based efforts to adapt the method to visualization-specific needs. We postulate that the framework-based approach holds the most promise for future progress in development of visualization-specific heuristics, and propose a specific framework as a starting point. We then recommend a method for community involvement and input into the further development of the heuristic framework and more detailed design and evaluation guidelines

    Grapevine yellows: Comparison of different procedures for DNA extraction and amplification with PCR for routine diagnosis of phytoplasmas in grapevine

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    In order to devise a procedure to be used as reference for detection of grapevine phytoplasmas and monitoring of Flavescence dorée, 12 combinations comprising three methods of plant DNA extraction and 4 procedures for amplification in polymerase chain reaction of phytoplasma DNA were examined in parallel using the same plant tissues infected with phytoplasmas. In a first series tissues of periwinkles (Catharanthus roseus) infected with phytoplasma isolates of the Elm yellows group (16SrV) and maintained in the greenhouse, were used. In a second series tissues of grapevines (Vitis vinifera) naturally infected with Flavescence dorée or Palatinate grapevine yellows phytoplasma were used. The DNA preparations obtained with each of the three extraction procedures were used undiluted or serially diluted, as target DNA in the 4 nested-polymerase chain reactions. The results showed differences in the efficiency among different methods of extraction as well as in the sensitivity among the DNA amplification procedures, which improved when DNA extracted from field grapevines was diluted. After additional comparative validation on numerous field-collected samples of GY-affected grapevines, the quickest extraction procedure was selected for use in routine diagnosis, with nested-PCR amplification either of ribosomal DNA or of the FD9 DNA fragment specific for Flavescence dorée and other 16SrV group phytoplasmas

    Avaliação da presença de metais pesados em nove méis produzidos e comercializados no Distrito Federal.

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    Resumo: O mel brasileiro é produzido principalmente por abelhas africanizadas a partir do néctar ou da secreção das plantas e, devido às suas características genéticas dessas espécies de abelhas, dispensa o uso de antibióticos e pesticidas, como acaricidas e fungicidas. A composição das amostras de méis está intimamente relacionada com o tipo de florada utilizada por estas abelhas para a elaboração do produto final. Um dos componentes de grande importância são os minerais presentes no mel que representam de 0,02% a 1%. Dentre estes minerais observamos os chamados metais pesados, que podem indicar tanto a origem geográfica do mel quanto o nível de poluição ambiental por estes metais. Logo, faz-se necessário a pesquisa da presença ou não de metais pesados nas amostras comercializadas. Por isso, o objetivo deste trabalho foi analisar nove amostras provenientes de nove apiários localizados na região do Distrito Federal, quanto à presença de metais de Cádmio, Chumbo, Cobre, Cromo, Níquel e Zinco. As determinações foram realizadas por espectrometria de emissão atômica com plasma acoplado e os resultados demonstraram que as concentrações de Cádmio e Zinco estão em conformidade com a legislação vigente. As concentrações dos demais metais (Chumbo, Cobre, Cromo e Níquel) estão abaixo do limite de detecção. [Evaluation of the presence of heavy metals in nine honeys produced and marketed in the Federal District]. Abstract: The Brazilian honey is mainly produced by Africanized bees that due to their genetic characteristics dispense the use of antibiotics and pesticides, acaricides and fungicides. However, it is necessary to investigate the presence or absence of heavy metals in marketed samples. Therefore, the aim of this study was to analyze nine samples from nine apiaries located in the Federal District, as the presence of metals Cadmium, Lead, Copper, Chromium, Nickel and Zinc. The determinations were performed by atomic emission spectrometry with inductively coupled plasma and the results showed that the concentrations of Cadmium and Zinc are in accordance with current legislation. The concentrations of other metals (Lead, Copper, Chromium and Nickel) are below the detection limit

    Antenatal Microbial Colonization of Mammalian Gut

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    The widely accepted dogma of intrauterine sterility and initial colonization of the newborn during birth has been blurred by recent observations of microbial presence in meconium, placenta, and amniotic fluid. Given the importance of a maternal-derived in utero infant seeding, it is crucial to exclude potential environmental or procedural contaminations and to assess fetal colonization before parturition. To this end, we analyzed sterilely collected intestinal tissues, placenta, and amniotic fluid from rodent fetuses and tissues from autoptic human fetuses. Total bacterial DNA was extracted from collected samples and analyzed by Next Generation Sequencing (NGS) techniques using hypervariable 16S ribosomal RNA (rRNA) regions (V3-V4). Colonizing microbes were visualized in situ, using labeled probes targeting 16S ribosomal DNA by fluorescent in situ hybridization. The NGS analysis showed the presence of pioneer microbes in both rat and human intestines as well as in rodent placentas and amniotic fluids. Microbial communities showed fetus- and dam-dependent clustering, confirming the high interindividual variability of commensal microbiota even in the antenatal period. Fluorescent in situ hybridization analysis confirmed the microbes' presence in the lumen of the developing gut. These findings suggest a possible antenatal colonization of the developing mammalian gut

    Visualizing Natural Image Statistics

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    Natural image statistics is an important area of research in cognitive sciences and computer vision. Visualization of statistical results can help identify clusters and anomalies as well as analyze deviation, distribution and correlation. Furthermore, they can provide visual abstractions and symbolism for categorized data. In this paper, we begin our study of visualization of image statistics by considering visual representations of power spectra, which are commonly used to visualize different categories of images. We show that they convey a limited amount of statistical information about image categories and their support for analytical tasks is ineffective. We then introduce several new visual representations, which convey different or more information about image statistics. We apply ANOVA to the image statistics to help select statistically more meaningful measurements in our design process. A task-based user evaluation was carried out to compare the new visual representations with the conventional power spectra plots. Based on the results of the evaluation, we made further improvement of visualizations by introducing composite visual representations of image statistics
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