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Guarapuava, Brazil

Caon D.,Federal Technological University of Parana | Genu A.M.,Rua Simeao Camargo Varela de Sa
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2013

Soil sampling and initial mapping process, when performed inefficiently, can lead to erroneous planning regarding the application of fertilizers. The objectives of this study were to establish a sampling density that provides accurate maps of the chemical attributes generated for different sampling densities in two depths, and to measure their practical implications in fertilization and liming for soybean on an Oxisol in the region of Guarapuava. Maps were compared for the attributes pH, H+Al, P, K, Ca, Mg, base saturation and the lime requirement, in the layers 0-10 and 0-20 cm, in the sampling densities of 1/4, 1/2, 1, 2 and 4 ha, being the first density taken as a reference for comparison. The methods of comparison were the overall accuracy and Kappa index. The decrease in sample density depreciated the quality of the generated maps. All sampling densities differ as to the accuracy, however, showed good levels of accuracy for the sample density of one sample per hectare. Precision agriculture uses in a better way the amount of lime and fertilizer than conventional agriculture. Source

Oliveira O.M.M.F.,Sao Paulo State University | Brunetti I.L.,Sao Paulo State University | Khalil N.M.,Rua Simeao Camargo Varela de Sa
Anais da Academia Brasileira de Ciencias | Year: 2015

In this study, the effect of nicotine on the LDL oxidation by the MPO/H2 O2 /Cl- system and the effect of HOCl on LDL and some of its components, such as methyl linoleate, vitamin E and the amino acid tryptophan were explored. Nicotine, in micromolar concentrations, enhanced the tryptophan oxidation, either present in LDL or free, in solution. Nicotine also decreased the formation of conjugated dienes and oxygen consumption in a methyl linoleate / HOCl system, and there was evidence to suggest an increase in chlorohydrin formation. Acceleration of the vitamin E oxidation by HOCl was also observed in the presence of nicotine. These data show that the interaction of nicotine and HOCl can promote significant biochemical modifications in LDL particle and some of its components involved in the pathogenesis of cardiovascular and other diseases. © 2015, Anais da Academia Brasileira de Ciencias.All rights reserved. Source

Denega S.,Rua Simeao Camargo Varela de Sa | Biasi L.A.,Federal University of Parana | Zanette F.,Federal University of Parana
Semina:Ciencias Agrarias | Year: 2010

The aim of this work was to characterize the phenological cycle of nine Vitis rotundifolia cultivars during the 2004/2005 season. The cultivars were Bontiful, Creek, Dixie, Magnolia, Magoon, Noble, Regale, Roanoke e Topsail. The experiment was performed on an orchard implanted in 1999 at the Canguiri Experimental Station of the Federal University of Paraná in Pinhais-PR. The phenology of two adult plants of each cultivar was monitored. The recorded phenological stages were: 1) Dormant bud; 2) Swollen bud; 3) Wool bud; 4) Green tip; 5) Bud burst (first leaf appearance); 6) Two to three leaves unfolded; 7) Five to six leaves unfolded; 8) Fully developed inflorescence; 9) Trace bloom (flowerhoods detached); 10) Full flowering (50% of the flowerhoods fallen); 11) Fruit set; 12) Groat-sized berries; 13) Pea-sized berries; 14) 50% filled berries (beginning to touch berries); 15) Final size; 16) Color change; 17) Berries ripe for harvest; and 18) End of harvesting. A very long phenological cycle was observed when compared to species such as Vitis vinifera and Vitis labrusca. These evaluations allowed us to conclude that: a) there is no difference in the phenological cycle periods between bronze and dark skinned cultivars; b) cultivars presented desuniform wool bud to full flowering cycle, ranging from 25 days ('Regale') to 81 days ('Creek'); c) the cultivar Regale presented the longest cycle (203 days) from full flowering to harvest and the cultivar Creek the shortest (136 days). The evaluated cultivars additionally presented desuniform ripening and a tendency to drop berries. Source

The obtention of soil quantitative information by non destructive techniques, like remote sensing and digital elevation model (DEM) open a possibility of faster and cheaper evaluation on soil studies. This study aims at verifying the possibility of quantifying soil atributtes through ASTER orbital sensor data and topographic features. The study area, with 184 ha, located in Rafard County, São Paulo State, Brazil, was sampled in a grid way collecting 1 sample/ha. Reflectance data was obtained from ASTER image and topographic features from DEM. Then, using orbital an topographic data were generated a multiple regression equation for soil attributes. The dependent variables were selected by a forward stepwise method. After that, the models with R2 > 0.50 were tested with unknown soil samples and the estimated values (VE) and the determined values (VD) were evaluated through scatterplots. SiO2, Fe2O3, TiO2 and clay attributes were tested and, Fe2O3 and clay obtained higher values of determination coefficient. It is conclude that the models generated with spectral data and topographic information allowed the quantification of the above cited soil components. Source

Viomar A.,Rua Simeao Camargo Varela de Sa | Vanjura B.,Rua Simeao Camargo Varela de Sa | De FaTima Oliveira M.,Federal Technological University of Parana | Rogerio Pinto Rodrigues P.,Rua Simeao Camargo Varela de Sa
Materials Science Forum | Year: 2015

Carbon steel is widely employed in the production of parts and machinery which supply the most diverse industrial sectors, such as the production of domestic appliances and cars. However, it presents low chemical resistance, being necessary the superficial treatment with anticorrosion substances. Most conventional surface treatments present harmful components to the environment and to life in general, as for instance, nickel, which is used in the phosphatization processes. More recently, researchers have been pointing to surface treatments which employ nanoceramics as potential substitutes to phosphatization. This study aims to develop a nanoceramic treatment to the carbon steel 1008, based on self-assembling molecule (SAM) and titanium dioxide. Carbon steel samples were SAM treated and then immersed in a solution containing TiO2. A chemometric study was developed to evaluate the best treatment conditions, using the software Designer Expert. For the electrochemical characterization, electrochemical impedance spectroscopy (EIS) tests were carried out. Results revealed that the SAM + TiO2 coating presents higher resistance to polarization than the samples treated with zinc phosphate, in a 0.01 mol L-1 sulphur acid medium. © (2015) Trans Tech Publications, Switzerland. Source

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