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Search Results: 1 - 10 of 67051 matches for " José;Levien "
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Métodos de preparo de solo e sua influência na eros?o hídrica e no acúmulo de biomassa da parte aérea de Eucaliptus Saligna em um cambissolo háplico da depress?o central do Rio Grande do Sul
Baptista, José;Levien, Renato;
Revista árvore , 2010, DOI: 10.1590/S0100-67622010000400001
Abstract: the study sought to identify and quantify the effect of methods of tillage soil and solid waste management of the harvest on water erosion and initial development of the forest in a inceptisoil. the test was installed in an experimental area of aracruz pulp and paper s. a., located in the municipality of arroio dos ratos in the physiografic region called the depression center. the experimental design used was random block with three repetitions. the treatments tested were interrupted ripping with residue (crs), continuous ripping with residue (scr), continuous without residue (ssr) all in the direction of the slope and mechanical digging (cme). the loss of soil from ssr was ten times larger than the other treatment of ripping and one hundred times greater if compared to mechanic digging. the water disposed superficial treatment with residue was 1.6%. in ripping without residue, disposal was 2.9% of the total precipitate. the more intensive preparation increases soil erosion but favors the initial growth of eucalyptus. the maintenance of residue provides an appropriate development of eucalyptus plants and reduces the loss of water, and soil.
Balan?o de nutrientes em povoamento de Eucalyptus saligna implantado sobre Cambissolo Háplico no RS
Mazurana, Michael;Baptista, José;Levien, Renato;Conte, Osmar;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2011, DOI: 10.1590/S1415-43662011000900008
Abstract: the forest system fragility can be evaluated through nutrient balance, with an emphasis in the cycling efficiency to maintain or elevate of productivity of system. the objective of this study was to evaluate the effects of different soil tillage systems on nutrient losses transported by erosion on an inceptisol with eucalyptus saligna. four tillage systems were tested: interrupted deep chiseling with residue (sir), continuous deep chiseling with residue (scr), continuous deep chiseling without residue (ssr) and mechanical pitting (cme). the sir system showed the greatest nutrient losses. the loss of nutrients was higher by water erosion, in the following order, k > ca > mg > p > cu > b. sir and ssr tillage systems had the highest levels of nutrients in shoots and lower nutritional balance, respectively.
Rela??es entre cátions trocáveis do solo e suas correla??es com a qualidade de frutos de mel?o
Miranda, Neyton de Oliveira;Medeiros, José F. de;Levien, Sérgio Luiz A.;
Horticultura Brasileira , 2008, DOI: 10.1590/S0102-05362008000200029
Abstract: melon fruit quality can be reduced by soil nutrient excess and imbalance, both caused by excessive and non uniform fertilizations. soil samples were taken from two melon fields aiming to identify, among soil cationic ratios (k:(ca+mg), k:ca, k:mg, k:ctc, ca:mg, ca:ctc, mg:ctc, na:ca, na:mg, and esp), those better correlated with fruit quality characteristics (pulp thickness, pulp firmness and total soluble solids (sst)). descriptive statistics, spearman's correlation and multiple regressions were used in the analysis. melon fruit quality characteristics presented few correlation with soil cationic ratios. in goldex, the best correlation found were of k:ctc with pulp fruit thickness; ca:ctc and mg:ctc with pulp firmness and of k:ctc, k:ca, k:(ca+mg), na:ca and na:mg with sst, all positive. in orange flesh, only pulp firmness showed correlation with ca:ctc (positive), k:mg, k:ca, k:(ca+mg) and na:ca (negative). on the basis of their contribution to regressions in orange flesh, cationic ratios identified as more important were ca:ctc for pulp fruit thickness (6,2%) and pulp firmness (10,9%), and mg:ctc for total soluble solids (1,5%).
Causas da varia??o em produtividade e qualidade do mel?o em um Latossolo Vermelho-Amarelo fertirrigado
Miranda, Neyton de Oliveira;Oliveira, Teógenes Senna de;Medeiros, José Francismar de;Levien, Sérgio Luiz Aguilar;
Ciência Rural , 2006, DOI: 10.1590/S0103-84782006000200019
Abstract: this work was carried out in mossoró, rn, brazil, with the objective of identifying soil and fertirrigation variables influencing melon yield and quality. variables determinated were: yield (export and marketable type); quality (total soluble solids content and pulp firmness); fertirrigation (emitter discharge rate, elevation, distance to water inlet and fertilizer amount); soil chemical properties (ph, organic matter, ca, mg, k, na, potential acidity, p, cu, zn, fe and mn) and physical properties (contents of clay, sand and silt, soil density and soil moisture). descriptive statistics, spearman's correlation and multiple regressions were used for data analysis. fertirrigation and variables related to a higher water availability improved melon yield and decreased quality. a higher availability of p increased melon yield, while higher soil ph improved fruit quality. levels of micronutrients fe and mn were harmful to the crop, however higher contents of cu increased export type yield and total soluble solids content.
Avalia??o de cápsulas de ceramica e instrumentos de medida de tens?o usados em tensi?metros
Moraes, Neuzo B. de;Medeiros, José F. de;Levien, Sérgio L. A.;Oliveira, Alison M. de S.;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2006, DOI: 10.1590/S1415-43662006000100009
Abstract: the objective of this work was to evaluate the efficiency of ceramic capsules from the state of ceara, brazil, and from the united states, as well as, to test the performance of the pressure transducer coupled in the air chamber tensiometer in field conditions, in two different depths, in the quantification of the matricial potential of the water in the soil, in comparison with those of the conventional tensiometers (mercury manometer). the field work was accomplished in mossoró, in the state of rio grande do norte, brazil, using a 2 x 2 x 2 experimental design in completely randomized blocks the factor being: origin of the capsules; tension measurement and depths. measurements were accomplished in a period of 40 consecutive days. it was verified that in the field tests the origin of the capsules provided same tension values, although the capsules from ceara state presented higher conductance than the ones from usa. the tension values obtained by the instruments of tension measurements differed statistically, although the difference was within the precision (1.0 kpa). a high correlation exists among the tensions obtained by the two instruments of tension measurement.
Balan o hídrico e da salinidade do solo na bananeira irrigada com água de diferentes salinidades = Soil water and salinity balance on banana irrigated with water of varied salinity
Ancélio Ricardo de Oliveira Gondim,José Francismar de Medeiros,Sérgio Luís Aguilar Levien,Gilcimar Alves do Carmo
Acta Scientiarum : Agronomy , 2009,
Abstract: O objetivo deste trabalho foi avaliar o efeito de diferentes níveis de salinidade de água de irriga o no uso consultivo na fase reprodutiva da bananeira e evolu o da salinidade do solo. Adotou-se o delineamento inteiramente casualizado em parcelas subdivididas, totalizando oito tratamentos com quatro repeti es por tratamento. Os níveis de salinidade foram obtidos a partir de águas naturais de po os dos aquíferos arenito e calcário e foram misturadas em tanques de alvenaria para a obten o das concentra es de salinidade desejada. Verificou-se que a área do bulbo com umidade superior a 8% representa aproximadamente 50% do volume do solo. A evapotranspira o da cultura diminuiu com o aumento da salinidade entre os tratamentos, o kc médio no período variou de 1,01 a 1,09 em águas de salinidade extremas. Comparando os perfis da salinidade do solo, verificou-se quea concentra o de sais foi superior na camada superficial aos 440 dias após plantio. The objective this work was to evaluate the advisory use of two cultivars banana and the salinity of the soil in different water salinity levels (0.55; 1.70; 2.85; and 4.00 dS m-1) during the reproductive phase. The experimental design chosen was randomizedcomplete blocks in subdivided plots, totaling eight treatments with four repetitions per treatment. The salinity levels were obtained from natural waters of wells from sandstone and calcareous aquifers and were mixed in masonry tanks in order to obtain the desiredsalinity concentrations. It was verified that the area of the bulb with moisture greater than 8% represents approximately 50% of the volume of the soil. The evapotranspiration of the culture decreased with the increase in the salinity among the treatments; the average kc in the period varied from 1.01 to 1.09 in waters of extreme salinity. Comparing the salinity profiles of the soil, it was verified that the concentration of salts was highest on the surfacelayer at 440 days.
Causas da varia o em produtividade e qualidade do mel o em um Latossolo Vermelho-Amarelo fertirrigado
Miranda Neyton de Oliveira,Oliveira Teógenes Senna de,Medeiros José Francismar de,Levien Sérgio Luiz Aguilar
Ciência Rural , 2006,
Abstract: Este trabalho foi realizado em Mossoró, RN, para identificar variáveis da fertirriga o e atributos do solo influenciando a produtividade e qualidade de frutos de mel o. Foram realizadas determina es de produtividade (tipo exporta o e comerciável); qualidade (sólidos solúveis totais e firmeza de polpa); fertirriga o (vaz o, eleva o, distancia até a entrada de água e quantidade de adubo aplicada); características químicas do solo (pH, matéria organica, P, Ca2+, Mg2+, K+e Na+, acidez potencial, Cu, Zn, Fe e Mn) e físicas (argila, areia, silte, densidade do solo e umidade). A estatística descritiva, a correla o de Spearman e a regress o múltipla foram usadas para analisar os dados. A fertirriga o e variáveis relacionadas à maior disponibilidade de água favoreceram a produtividade e prejudicaram a qualidade de frutos. A maior disponibilidade de P no solo aumentou a produtividade, enquanto os maiores pH do solo melhoraram a qualidade dos frutos. Os micronutrientes Fe e Mn apresentaram teores prejudiciais à cultura, enquanto maiores teores de Cu favoreceram a produtividade tipo exporta o e o teor de sólidos solúveis totais.
Advances in the treatment of Raynaud’s phenomenon
Terri L Levien
Vascular Health and Risk Management , 2010, DOI: http://dx.doi.org/10.2147/VHRM.S4551
Abstract: dvances in the treatment of Raynaud’s phenomenon Review (6735) Total Article Views Authors: Terri L Levien Published Date March 2010 Volume 2010:6 Pages 167 - 177 DOI: http://dx.doi.org/10.2147/VHRM.S4551 Terri L Levien Drug Information Pharmacist and Clinical Associate Professor, College of Pharmacy, Washington State University Spokane, WA, USA Abstract: Raynaud’s phenomenon is a common condition characterized by vasospasm of the digital arteries and resulting cyanosis and redness. It often does not require pharmacologic management, but in some cases symptoms are severe and pharmacologic management is necessary. Calcium channel blockers are often used first-line, but in some patients are ineffective. Patients with severe symptoms or intolerance to available therapies have prompted exploration of alternative therapies, including endothelin antagonists, phosphodiesterase-5 inhibitors, antioxidants, newer vasodilators, statins, and botulinum toxin. These newer therapies provide the focus for this review.
Advances in the treatment of Raynaud’s phenomenon
Terri L Levien
Vascular Health and Risk Management , 2010,
Abstract: Terri L LevienDrug Information Pharmacist and Clinical Associate Professor, College of Pharmacy, Washington State University Spokane, WA, USAAbstract: Raynaud’s phenomenon is a common condition characterized by vasospasm of the digital arteries and resulting cyanosis and redness. It often does not require pharmacologic management, but in some cases symptoms are severe and pharmacologic management is necessary. Calcium channel blockers are often used first-line, but in some patients are ineffective. Patients with severe symptoms or intolerance to available therapies have prompted exploration of alternative therapies, including endothelin antagonists, phosphodiesterase-5 inhibitors, antioxidants, newer vasodilators, statins, and botulinum toxin. These newer therapies provide the focus for this review.Keywords: Raynaud, iloprost, bosentan, phosphodiesterase-5 inhibitors
Necessidade hídrica do meloeiro irrigado com água de diferentes salinidades e cultivado com ou sem cobertura do solo
Medeiros, Francisco A. S. B. de;Medeiros, José F. de;Silva, Marcelo C. de C.;Alves, Leonardo P.;Souza, Tonny H.de;Levien, Sérgio L. A.;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2005, DOI: 10.1590/S1415-43662005000200014
Abstract: the water requirement of the crops can be estimated from the reference evapotranspiration (eto) and crop coefficients (kc). aiming to estimate the water requirement of two cultivars of melon (gold mine and trusty) cultivated with and without soil covering with polyethylene film and irrigated by trickle irrigation with water of different salinities (1.2, 2.5 and 4.4 ds m-1), an experiment was installed in the municipal district of mossoró, rn, in an alfissol. to obtain the water requirement of the crop the water balance was accomplished in the plots, obtaining the crop coefficients. to obtain the variation in water storage in the soil profile and the subsurface flow three tensiometers were installed in each plot of two experimental blocks. the irrigation was estimated daily using eto and kc recommended by fao and was adjusted in agreement with the monitoring of the soil moisture. in water of higher salinity the evapotranspiration of the melon plant was reduced by 14%; the soil covering reduced it by 18%; and the cultivar trusty evapotranspirated 11% less than the gold mine. the water balance allow to estimate the crop coefficient of melon plants for different salinities, soil covering and cultivars.
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