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Search Results: 1 - 10 of 69750 matches for " ROGéRIO ANT?NIO SILVA "
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Effects of pesticides on eggs of Chrysoperla externa (Neuroptera: Chrysopidae) and consequences on subsequent development Efectos de los plaguicidas en huevos de Chrysoperla externa (Neuroptera: Chrysopidae) y las consecuencias sobre su desarrollo
ROGéRIO ANTNIO SILVA,GERARDO ANDRADE CARVALHO,CéSAR FREIRE CARVALHO,DIEGO BASTOS SILVA
Revista Colombiana de Entomología , 2012,
Abstract: The effects of six pesticides applied to the coffee crop on eggs and their consequences on the subsequent developmental stages of Chrysoperla externa (Neuroptera: Chrysopidae) were evaluated under laboratory conditions. The pesticides and water (control) were sprayed on eggs using a Potter's tower. After spraying, forty eggs per treatment were individualized in glass tubes and maintained in a climatic chamber, in order to evaluate immature development of this predator. The treatments showed significant differences for egg viability and survival of first-instar larvae. Chlorpyrifos, sulphur and copper oxichlorate reduced the treated egg viability, whereas both sulphur and betacyfluthrin reduced the survival of first-instar larvae. Endosulphan and azociclotin reduced the daily oviposition of this green lacewing species. The harmless products (Class 1, E < 30%), can be recommended for use in integrated pest management programs in coffee crops, in order to preserve this predator. Los efectos de seis plaguicidas aplicados al cultivo de café sobre los huevos y etapas de desarrollo posteriores de Chrysoperla externa (Neuroptera: Chrysopidae), fueron evaluados bajo condiciones de laboratorio. Los plaguicidas y el agua (control) fueron aplicados en los huevos usando una torre de Potter. Después de la aplicación, cuarenta huevos por tratamiento fueron individualizados en tubos de vidrio y mantenidos en cámara bioclimática, con el objetivo de verificar las posibles anormalidades en el desarrollo de este depredador. Los tratamientos mostraron diferencias significativas para la viabilidad de los huevos y la supervivencia del primer instar larval. Chlorpyrifos, azufre y oxicloruro de cobre redujeron la viabilidad de los huevos tratados, mientras que el azufre y el betacyfluthrin redujeron la supervivencia del primer instar larval. Endosulfán y azociclotin redujo la oviposición diaria de esta especie crisopa. Los productos inocuos (Clase 1, E < 30%), pueden recomendarse para su uso en programas integrados de manejo de plagas en los cultivos de café, a fin de preservar este depredador.
épocas de emergência de Brachiaria brizantha no desenvolvimento da cultura da soja
Silva Andréia Cristina,Ferreira Lino Roberto,Silva Antnio Alberto da,Freitas Rogério Soares
Ciência Rural , 2005,
Abstract: A integra o agricultura-pecuária beneficia simultaneamente a produ o de gr os e a pecuária. Todavia, a forrageira tem sido a principal espécie daninha que compete com a cultura anual. Objetivou-se, neste trabalho, quantificar os efeitos de épocas de emergência de Brachiaria brizantha em rela o à cultura da soja. O experimento foi realizado em casa de vegeta o, avaliando-se sete épocas de emergência de B. brizantha em rela o à cultura da soja (-21, -14, -7, 0, 7, 14 e 21 dias da emergência da soja) e da soja em monocultivo. No estádio R2 da soja, foram determinados o número de colmos de B. brizantha, a área foliar e a parti o de biomassa seca de ambas as espécies e o número de folhas trifolioladas e de nós de soja. No estádio R8 da soja, foram avaliados a biomassa seca total da parte aérea e o número de colmos da forrageira, assim como a produ o de gr os por planta e o número de vagens por planta e de sementes por vagem da soja. A época de emergência da B. brizantha em rela o à da soja foi determinante no crescimento de ambas as espécies. Foi observada redu o da produ o de gr os por planta de soja consorciada, comparada ao monocultivo, de aproximadamente 97, 96, 91, 80, 34, 27 e 15% quando B. brizantha emergiu aos -21, -14, -7, 0, 7, 14 e 21 dias da emergência da soja, respectivamente, sendo o acúmulo de biomassa seca da parte aérea da forrageira nos respectivos tratamentos de 275, 279, 267, 202, 79, 46 e 23 gramas por vaso. Em ordem decrescente, a suscetibilidade das características morfológicas da soja, avaliadas no estádio R2, devido à interferência imposta por B. brizantha ocorreu da seguinte maneira: número de folhas trifolioladas e área foliar > biomassa seca de folhas, haste, raízes e nódulos > número de nós. O número de vagens por planta da soja consorciada foi semelhante ao do monocultivo quando B. brizantha emergiu aos 21 dias da emergência da soja, e o de sementes por vagem somente foi reduzido quando esta espécie emergiu a -21 e -14 dias da emergência da soja.
CARACTERíSTICAS FíSICAS E MICROBIOLóGICAS DO CENTRO TENDíNEO DIAFRAGMáTICO BOVINO CONSERVADO EM GLICERINA A 98% E NO GLUTARALDEíDO A 4%
Rogério Elias Rabelo,Gilberto Antnio Tavares,Neusa Margarida Paulo,Luiz Antnio Franco da Silva
Ciência Animal Brasileira , 2006,
Abstract: Realizaram-se testes físicos de tra o e alongamento até ruptura em dez tiras com 5 a 6 mm de largura, do exemplar in natura e dos respectivos exemplares conservados em glicerina a 98% e glutaraldeído a 4% por 30 dias para a avalia o da influência de ambos os conservantes sobre o tecido biológico, com vistas ao aproveitamento em cirurgias reparadoras. Paralelamente, avaliou-se a atividade anti-séptica dos conservantes, por meio de exames microbiológicos de fragmentos colhidos do material in natura e dos respectivos exemplares submetidos à conserva o. Os testes físicos mostraram que sete amostras conservadas em glutaraldeído a 4% suportaram maior for a de tens o, quando comparadas com os respectivos exemplares in natura e conservados em glicerina a 98%. Duas amostras apresentaram comportamento semelhante quanto ao ponto de rompimento, para ambos os conservantes. Apenas em uma amostra verificou-se que o material in natura apresentou um ponto de rompimento superior às amostras conservadas. Observou-se crescimento bacteriano apenas em quatro amostras no material in natura. Os mesmos exames realizados em amostras conservadas n o revelaram nenhum crescimento. Conclui-se que tanto a glicerina a 98%quanto o glutaraldeído a 4% demonstraram ser eficientes na conserva o do material, bem como na atividade bactericida durante o período de 30 dias.
Propaga??o clonal de guanandi (Calophyllum brasiliense) por miniestaquia
da Silva,Rogério Luiz; de Oliveira,Mila Liparize; Marco Antnio,Monte; Xavier,Aloisio;
Agronomía Costarricense , 2010,
Abstract: guanandi (calophyllum brasiliense) clonal propagation through minicuttings. the goal of this research was to determine guanandi (calophyllum brasiliense) clonal propagation efficiency of hisforesty species through minicutting technique. a miniclonal garden was first established in sand beds, where new sprouts were produced for their use as minicuttings. two experiments were performed in order to refine propagation protocols. the first experiment assessed the performance of 2 different types of minicuttings (apical and intermediate within the sprout) exposed to three iba dosages (0, 2000, 4000, and 8000 mg.l-1). in the second experiment, minicuttings were sown in 3 different substrates (vermiculite, burned rice husk and decomposed pine-bark). rooting percentages did not vary among treatments in the first experiment. in the second experiment, a greenhouse-permanency time reduction, under vermiculite substrate condition, was registered. as a general conclusion, the minicutting technique was an efficient strategy for guanandi clonal propagation.
Qualidade da água do Ribeir?o Lavrinha na regi?o Alto Rio Grande - MG, Brasil
Pinto, Daniel Brasil Ferreira;Silva, Antnio Marciano da;Mello, Carlos Rogério de;Coelho, Gilberto;
Ciência e Agrotecnologia , 2009, DOI: 10.1590/S1413-70542009000400028
Abstract: the main purpose of this work was to study the surface water quality behavior, continuously throughout the time, at the headwater watershed of the grande river, mg. the watershed drains into grande river area of 687 ha and is enclosed by the mantiqueira mountains. the samples were collected at six points in lavrinha stream, main tributary of the watershed, from may 2006 to january 2007, with a total of seven evaluations for each point. current watershed land use map was developed through gps device, based on field observations. the parameters evaluated were: hydrogen potential (ph), dissolved oxygen (do), electric conductivity (ec), salinity, temperature, biochemical oxygen demand (bod), chemical oxygen demand (cod), nitrate (no3-), ammonia (nh3), phosphorous (po4), turbidly, total soil, total dissolved soil (tds), fecal coliform (escherichia coli), total coliform. water quality index (wqi), proposed by "minas gerais state water resources institute" (igam), was calculated for all samples, classifying the water quality class according to conama resolution 357/05. the environmental conditions reflected on wqi values as well as on conama water quality classification. it was evidenced that the main parameter of the critical situation of the water quality at watershed was the fecal and total coliform, which is associated to livestock. although less important than coliform, do and bod are also limiting parameters at watershed.
Elabora??o e implementa??o de um programa para verifica??o dos cálculos das unidades monitoras em radioterapia
Müller, Márcio Rogério;Rodrigues, Laura Natal;Silva, Marco Antnio da;
Radiologia Brasileira , 2005, DOI: 10.1590/S0100-39842005000600007
Abstract: objective: to develop and implement a software based on the manual calculation algorithm for verification of the calculations in radiotherapy monitor units and to establish acceptance levels as a mechanism of quality assurance. materials and methods: data were obtained from clinac 600c and 2100c varian linear accelerators and the computerized treatment planning system used was cadplan?. results: for the 6 mv beams the acceptance levels for deviations among the calculations of monitor units, divided by treatment area, were the following: breast (0.0% ± 1.7%), head and neck (1.5% ± 0.5%), hypophysis (-1.7% ± 0.5%), pelvis (2.1% ± 2.1%) and thorax (0.2% ± 1.3%). for the 15 mv beams the suggested level for pelvis in all the treatment techniques was (3.2% ± 1.3%). conclusion: the present data are sufficient to justify the use of the software in the clinical practice as a tool for the quality assurance program.
Simula??o da variabilidade espacial da eros?o hídrica em uma sub-bacia hidrográfica de Latossolos no sul de Minas Gerais
Silva, Antnio Marciano da;Mello, Carlos Rogério de;Curi, Nilton;Oliveira, Polyanna Mara de;
Revista Brasileira de Ciência do Solo , 2008, DOI: 10.1590/S0100-06832008000500033
Abstract: simulation of water erosion spatial distribution is an important tool for soil conservation planning in watersheds, being an important application of the universal soil loss equation (usle) using interpolation principles, such as geostatistics. this study aimed to simulate spatial distribution of water erosion in a watershed of the alto rio grande (mg) region, applying geostatistical tools for mapping, considering different land use scenarios. water erosion was estimated by the usle applied to grid cells, weighing pedologic units and land use distribution in each cell. the topographical factor (ls) of the cells was obtained based on a digital elevation model of the sub-watershed, identifying length and main flow direction. mean annual rainfall erosivity in the region is 8,030 mj mm ha-1 h-1 year-1 and the underlying soil erodibility values were based on data from the literature. mapping was carried out considering the current land uses in the entire watershed, where eucalyptus was grown on degraded soils, grasses planted as pasture and corn tilled conventionally. under the current land uses, soil losses from the watershed were not relevant, except in areas covered with eucalyptus and grass on cambisol (inceptisol). in all simulations, the highest soil losses were verified on the eastern side of the watershed, especially for eucalyptus and conventional corn on cambisol and dystrophic red-yellow latosol (oxisol), where special soil conservation techniques are needed.
Aplicabilidade do lisem (limburg soil erosion) para simula??o hidrológica em uma bacia hidrográfica tropical
Gomes, Natalino Martins;Mello, Carlos Rogério de;Silva, Antnio Marciano da;Beskow, Samuel;
Revista Brasileira de Ciência do Solo , 2008, DOI: 10.1590/S0100-06832008000600025
Abstract: the most important parameters of the lisem model associated to surface runoff production (antecedent soil moisture (θap) and soil layer thickness), were calibrated by individual precipitation events in the marcela creek watershed, alto rio grande region, mg. the hydrological effects of different land-uses in the watershed were also simulated. the model was highly sensitivity to soil moisture, which was the most important calibration paramete. the influence of the water balance layer was related to the soil moisture during calibration. it was observed that the deeper the soil layer, the greater the soil moisture required to calibrate the model. results of simulation showed that the peak discharges were reduced under native forest, eucalyptus plantation and 35 months-old coffee plantation, respectively, by 37.6; 42.2 and 28.0 %, in the case of a precipitation event of 48 mm h-1. the results of the hydrological model lisem in hydrological simulations of direct surface runoff were satisfactory, suggesting that it may be used for hydrological behavior prediction in tropical watersheds after adequately calibrated.
Estabilidade temporal do conteúdo de água em três condi??es de uso do solo, em uma bacia hidrográfica da regi?o da Serra da Mantiqueira, MG
ávila, Léo Fernandes;Mello, Carlos Rogério de;Silva, Antnio Marciano da;
Revista Brasileira de Ciência do Solo , 2010, DOI: 10.1590/S0100-06832010000600024
Abstract: the description of soil hydrological processes is relatively complex, especially in the case of moisture, which is influenced by edaphic, topographic, climatic and vegetation factors. under field conditions, an adequate sampling strategy is required to estimate soil moisture, considering variations in time and space. to represent the soil moisture adequately with less sampling effort and cost, the concept of temporal stability has often been applied. this study was carried out with the objective of analyzing the temporal stability of the surface soil moisture (0-0.20 m layer) under three land uses in an experimental area in a catchment of the mantiqueira range region, state of minas gerais, brazil, in the dry and rainy seasons, identifying the most representative points for monitoring. greatest temporal stability was observed in the wetland, less under atlantic forest and intermediate in a pasture area. significant variation was also observed in the mean relative difference between the sampling periods, indicating that the characteristics of each site should be particularly considered to choose the points. in the pasture area, only one point could be identified to monitor both periods (rainy and dry). on the other hand, in the atlantic forest and wetland areas two points were identified, one specifically for the rainy and the other for the dry season; so an individual analysis for each season is recommended.
Especificidade de hospedeiro nas intera??es Xanthomonas campestris pv. campestris - brássicas
Miguel-Wruck, Dulandula Silva;Oliveira, José Rogério de;Dias, Luiz Antnio dos Santos;
Summa Phytopathologica , 2010, DOI: 10.1590/S0100-54052010000200004
Abstract: considering the lack of information in literature about the pathogenic variability of brazilian isolates of xanthomonas campestris pv. campestris, a study was carried out to determine the pathogenic specificity of 33 isolates of this bacterium originated from several regions of brazil and overseas to eight different brassica species, through inoculation by means of injection of the bacterial suspension in leaves. from these isolates, 12 were obtained from collard greens (brassica oleracea var. acephala), nine from cabbage (b. oleracea var. capitata), five from cauliflower (b. oleracea var. botrytis), two from canola (b. napus), one from broccoli (b. oleracea var. italica), one from chinese cabbage (b. chinensis), one from kohlrabi (b. oleracea var. gongylodes) and two from radish (raphanus sativus). the pathogenicity of the bacterium isolates to the tested hosts indicated that 14 of them were not specific and originated symptoms on all inoculated plants. the other 19 isolates had showed relative degrees of specificity and did not cause disease in one or more of the tested brassicas.
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