151 research outputs found

    Avaliação da solarização do solo para o controle de Ralstonia solanacearum.

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    O presente trabalho avaliou o emprego da solarização como uma alternativa para o controle da murcha bacteriana, causada por Ralstonia solanacearum, em amostras de solo infestado com o patógeno, dispostas em bolsas de náilon e enterradas em parcelas solarizadas ou não. Dois experimentos foram instalados, um em Campinas (SP), de fevereiro a abril de 2001, e o outro em Piracicaba (SP), de dezembro de 2001 a janeiro de 2002. Os ensaios foram efetuados em delineamento inteiramente casualizado, esquema fatorial, com quatro repetições, tendo cada parcela 4 x 4 m. Os fatores avaliados foram a solarização (com ou sem), efetuada com filme plástico transparente de 100 µm de espessura, o período de tratamento (30 e 60 dias e 37 e 60 dias para o primeiro e o segundo experimentos, respectivamente) e a profundidade de colocação das amostras (10 e 20 cm), fator verificado apenas no segundo ensaio. Após os períodos estipulados de solarização, o solo de cada bolsa foi colocado em vasos, para os quais foram transplantadas mudas de tomateiro (Lycopersicon esculentum). No solo não solarizado, em ambos os experimentos, 43 a 100% dos tomateiros murcharam. No segundo experimento, 6 a 22% dos tomateiros murcharam no solo solarizado por 37 dias. Entretanto não foram detectadas plantas murchas nas parcelas solarizadas do primeiro experimento e no segundo ensaio nenhum tomateiro murchou solo solarizado por 60 dias, nas duas profundidades estudadas. Os resultados indicam que a solarização é uma técnica promissora para o controle de R. solanacearum

    Ericaceae do Parque Estadual da Serra do Papagaio, Minas Gerais, Brasil

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    O Parque Estadual da Serra do Papagaio está localizado na Serra da Mantiqueira, sul de Minas Gerais, abrigando um importante remanescente de Floresta Atlântica. Possui uma área de 22.917 ha., dos quais cerca de 50% apresenta altitudes acima de 1.800m. O levantamento florístico foi realizado entre os anos de 2009 e 2013 e os espécimes coletados foram depositados no Herbário Leopoldo Krieger (CESJ), da Universidade Federal de Juiz de Fora. O objetivo deste estudo foi apresentar o tratamento taxonômico para Ericaceae nesta unidade de conservação. Foram registradas 10 espécies pertencentes a três gêneros, sendo Gaultheria e Gaylussacia os mais ricos, ambos representados por quatro espécies cada, e Agarista representado por apenas duas espécies. São apresentadas chaves de identificação, descrições das espécies, ilustrações de caracteres diagnósticos e comentários de distribuição geográfica, ecológicos e taxonômicos

    Agronomic Characteristics, Chemical Composition and In vitro Gas Production of Sugarcane Cultivars (Saccharum spp.) for Feeding Ruminants.

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    solids content (BRIX), NDF/BRIX ratio and tons of sucrose/ha, total digestible nutrients, digestible energy, metabolizable energy, net energy and in vitro digestibility of organic matter, crude protein, neutral detergent fiber (NDF) and acid detergent, of digestion and In vitro gas production of nonfibrous carbohydrates, latency time, digestion rate and gas production of fibrous carbohydrates, and in vitro digestibility of organic matter. There was a significant difference between the cultivars regarding the neutral detergent fiber content, in vitro digestibility of organic matter, total digestible nutrients, digestible energy, net energy, degradation rates of fibrous and non-fibrous carbohydrates and latency period. There was a negative correlation between stem percentage and NDF/BRIX and positive correlation between in vitro digestibility of organic matter and total digestible nutrients. The results were submitted to analysis of variance and mean test by Scott-Knott and Pearson's correlation analysis. The statistical program used was SAEG 2000. The RB835486 variety was superior to the other cultivars, as it presented 93.28% of stem, 57.5% of in vitro digestibility of organic matter, NDF / BRIX ratio of 2.68, 43.78% NDF, latency period 2.86h and fibrous carbohydrate degradation rate of 2.26% per hour. Therefore, this cultivar was better indicated for animal feeding between May and July in the State of Mato Grosso, Brazil

    Challenges in a Free Air CO2 Enrichment (FACE) coffee crop experiment to prospect strategies for mitigation and adaptation to climate change.

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    Huge research efforts have been undertaken to understand how plants and ecosystems, natural or agroecosystems, will respond to increasing CO2 in the atmosphere. In this context, several FACE field experiments were implemented and are underway, with the mission of subsidizing responses to diverse crops, forests, pastures and desert areas. FACE experiments allows the exposure of the plants to high concentrations of CO2 (eCO2) in natural environments, providing ideal conditions for the study impact of CO2 increase. The scientific information obtained through the implementation of the project and the aggregation of partners from other research institutions, can supply with information several policies on climate change

    Avaliação da porosidade e densidade de um latossolo argiloso situado no Triangulo Mineiro.

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    A Qualidade do Solo pode ser conceituada como a capacidade que um determinado tipo de solo apresenta, em ecossistemas naturais ou agrícolas, para desempenhar uma ou mais funções relacionadas à sustentabilidade. Nessa perspectiva é fundamental o monitoramento da qualidade física deste solo. Uma alternativa para o monitoramento das alterações nos atributos físicos do solo decorrentes da ação antrópica podem ser feitos através de estudos utilizando solos cultivados e sob mata nativa, desde que mantidos os critérios genéticos e topográficos relacionados com a formação dos solos. Com isso o objetivo deste estudo foi comparar a porosidade e densidade de um Latossolo Vermelho distrófico de textura argilosa submetido à ação antrópica com um ambiente natural. O experimento foi realizado no município de Uberlândia entre as latitudes 19º12?46,71??S e 19º12?52,73??S e longitudes 48º08?14,62??O e 48º08?20,16??O. O clima é do tipo Cwa de acordo Köppen. O solo é classificado como Latossolo Vermelho Amarelo distrófico. O Cerrado natural apresentou parâmetros de densidade e porosidade próximos ?dos ideais? para este tipo de solo, podendo então ser utilizado como parâmetro comparação destes Latossolos, submetidos a ação antrópica. A pastagem degrada, apresenta piores resultados de densidade e porosidade, evidenciando a necessidade de se olhar a pastagem como se fosse uma cultura como soja, milho por exemplo. A cana de açúcar devido a tecnologia na qual é submetida apresenta maiores valores de densidade e microporosidade nos primeiros centímetros do solo, devido ao grande trafego de máquinas que ocorre desde a implantação até a colheita

    Determinação de compostos de massa molecular alta em folhas de plantas da Amazônia

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    The fractIons of dichloromethane extracts of leaves from andiroba (Carapa guianensis - Meliaceae), caapi (Banisteriopsis caapi - Malpighiaceae), cocoa (Theobroma cacao - Sterculiaceae), Brazil nut (Bertholletia excelsa - Lecytidaceae), cupuaçu (Theobroma grandiflorum - Sterculiaceae), marupá (Simaruba amara - Simaroubaceae) and rubber tree (Hevea brasiliensis - Euphorbiaceae), were analyzed by HT-HRGC and HT-HRGC-MS. Esters of homologous series of fatty acids and long chain alcohols, phytol, amyrines and tocopherols were characterized. The characterization of the compounds was based mainly in mass spectra data and in addition by usual spectrometric data (1H and 13C NMR, IR)

    Can additive beta-diversity be reliably partitioned into nestedness and turnover components?

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    Aims: Quantifying β‐diversity (differences in the composition of communities) is central to many ecological studies. There are many β‐diversity metrics, falling mostly into two approaches: variance‐based (e.g., the Sørensen index), or diversity partitioning (e.g., additive β‐diversity). The former cannot be used when species–sites matrices are unavailable (which is often the case in island biogeography in particular) and only species richness data are provided. Recently, efforts have been made to partition additive β‐diversity, a metric calculated using only α‐diversity and γ‐diversity, into nestedness and turnover components (termed here “richness‐only β‐diversity partitioning”). We set out to test whether this form of β‐diversity partitioning generates interpretable results, comparable with metrics based on species incidence β‐diversity partitioning. Location: Global. Time period: Present day. Major taxa studied: Multiple taxa. Methods: We first provide a brief review of β‐diversity partitioning methods, with a particular focus on the development of richness‐only β‐diversity partitioning. Second, we use 254 empirical incidence matrices (provided with the paper) sourced from the literature to measure turnover and nestedness using incidence β‐diversity partitioning, comparing the resulting values with those calculated using richness‐only β‐diversity. Results: We provide an account of the emergence of β‐diversity partitioning, with particular reference to the analysis of richness‐only datasets, and to the definition and usage of the relevant metrics. Analytically, we report weak correlations between turnover and nestedness calculated using the two different approaches. We show that this is because identical values of α‐diversity and γ‐diversity can correspond to incidence matrices with a range of different structures. Main conclusions: Our results demonstrate that the use of richness‐only β‐diversity partitioning to measure turnover and nestedness is problematic and can produce patterns unrelated to conventional measures of turnover and nestedness. We therefore recommend that more accurate definitions are adopted for these terms in future studies.</br

    MAGGnet: an international network to foster mitigation of agricultural greenhouse gases.

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    Research networks provide a framework for review, synthesis and systematic testing of theories by multiple scientists across international borders critical for addressing global-scale issues. In 2012, a GHG research network referred to as MAGGnet (Managing Agricultural Greenhouse Gases Network) was established within the Croplands Research Group of the Global Research Alliance on Agricultural Greenhouse Gases (GRA). With involvement from 46 alliance member countries, MAGGnet seeks to provide a platform for the inventory and analysis of agricultural GHG mitigation research throughout the world. To date, metadata from 315 experimental studies in 20 countries have been compiled using a standardized spreadsheet. Most studies were completed (74%) and conducted within a 1-3-year duration (68%). Soil carbon and nitrous oxide emissions were measured in over 80% of the studies. Among plant variables, grain yield was assessed across studies most frequently (56%), followed by stover (35%) and root (9%) biomass. MAGGnet has contributed to modeling efforts and has spurred other research groups in the GRA to collect experimental site metadata using an adapted spreadsheet. With continued growth and investment, MAGGnet will leverage limited-resource investments by any one country to produce an inclusive, globally shared meta-database focused on the science of GHG mitigation

    Attending to warning signs of primary immunodeficiencies disease across the range of clinical practices

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    Purpose: Patients with primary immunodeficiency diseases (PIDD) may present with recurrent infections affecting different organs, organ-specific inflammation/autoimmunity, and also increased cancer risk, particularly hematopoietic malignancies. The diversity of PIDD and the wide age range over which these clinical occurrences become apparent often make the identification of patients difficult for physicians other than immunologists. The aim of this report is to develop a tool for educative programs targeted to specialists and applied by clinical immunologists. Methods: Considering the data from national surveys and clinical reports of experiences with specific PIDD patients, an evidence-based list of symptoms, signs, and corresponding laboratory tests were elaborated to help physicians other than immunologists look for PIDD. Results: Tables including main clinical manifestations, restricted immunological evaluation, and possible related diagnosis were organized for general practitioners and 5 specialties. Tables include information on specific warning signs of PIDD for pulmonologists, gastroenterologists, dermatologists, hematologists, and infectious disease specialists. Conclusions: This report provides clinical immunologists with an instrument they can use to introduce specialists in other areas of medicine to the warning signs of PIDD and increase early diagnosis. Educational programs should be developed attending the needs of each specialty.Fil: Costa Carvalho, Beatriz Tavares. Universidade Federal de São Paulo; BrasilFil: Sevciovic Grumach, Anete. Fundação ABC. Faculdade de Medicina; BrasilFil: Franco, José Luis. Universidad de Antioquia; ColombiaFil: Espinosa Rosales, Francisco Javier. Instituto Nacional de Pediatría. Unidad de Investigación en Inmunodeficiencias; MéxicoFil: Leiva, Lily E.. State University of Louisiana; Estados UnidosFil: King, Alejandra. Hospital de Niños Doctor Luis Calvo Mackenna. Unidad de Inmunología; ChileFil: Porras, Oscar. Hospital Nacional de Niños “Dr. Carlos Sáenz Herrera”; Costa RicaFil: Bezrodnik, Liliana. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Oleastro, Mathias. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Sorensen, Ricardo U.. State University of Louisiana; Estados Unidos. Universidad de La Frontera. Facultad de Medicina; MéxicoFil: Condino Neto, Antonio. Universidade de Sao Paulo; Brasi
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