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Search Results: 1 - 10 of 422396 matches for " José Saúl;Gómez-Delgado "
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Biomasa y rendimiento de frijol tipo flor de junio bajo riego y sequía
Acosta-Díaz, Efraín;Amador-Ramírez, Mario Domingo;Padilla-Ramírez, José Saúl;Gómez-Delgado, J. Patrocinio;Valadez-Montoya, Heladio;
Agricultura técnica en México , 2007,
Abstract: in the state of zacatecas, mexico 200 thousand ha of dry bean flor de junio class are annually sown, and its yield average is 315 kg ha-1. this low yield is due to intermittent drought during the growing season. the objective was to determine the effect of different soil moisture levels on plant maturity, shoot and root dry weight per plant, root-shoot ratio and yield of four bean genotypes. in 2002, two trials were conducted; one under greenhouse conditions and the other in the field at the unidad de agronomía of the universidad autónoma de zacatecas. in the greenhouse four soil moisture levels in 3 kg pots were evaluated; one without drought and three from moderate to severe stress: a) irrigated (r), 100% of the evapotranspired water was restituted every 12 h during the cycle, b) moderate drought (sm), 75% of the volume of r was restituted, c) severe drought (ss), 50% of the volume of r was restituted and d) moderate drought during the vegetative stage and severe drought during the reproductive stage (smv+ssr). in the field, two treatments were tested: rainfed (s), depending on rainfall and rainfed plus supplemental irrigation (s+r), with rainfall, contribution and three irrigations as needed. the stress treatments affected negatively all traits in the genotypes in comparison with r and s+r treatments in greenhouse and field, respectively. in the greenhouse; in comparison to the control (r) the average reductions observed with the smv+ssr treatment were: seven days to mature, 26% in shoot dry weight, 44% in root dry weight and 53% in yield. the negative effects increased accordingly to the drought level applied, except for root-shoot ratio, which increased with the stress. under field conditions, the average reductions under the rainfed treatment (s) as compared to (s+r) were: 13 days for maturity, 34% in shoot dry weight and 48% in yield. on the basis of yield reduction, drought susceptibility index and geometric mean of yield, lines uaz fj 2 and uaz fj 3 resulte
Proposal for the Introduction of the Spatial Perspective in the Application of Global Sensitivity Analysis  [PDF]
Wenseslao Plata-Rocha, Montserrat Gómez-Delgado, Joaquín Bosque-Sendra
Journal of Geographic Information System (JGIS) , 2012, DOI: 10.4236/jgis.2012.46055
Abstract: In any model, Sensitivity Analysis (SA) is a fundamental process to improve the robustness and credibility of the results, as part of validation procedure. Generally, SA determined how the variation in the model output can be apportioned to different sources of variations, and how the given model depends upon the information fed into it. Many complex techniques of SA have been developed within the field of numerical modeling; however, they have limited applications for spatial models, as they do not consider variations in the spatial distributions of the variables included. In this research, a variation in the implementation of a Global Sensitivity Analysis (E-FAST) is proposed in order to include the spatial level. For this purpose the conventional tools available in a raster Geographical Information System (GIS) are used. The procedure has been tested in a simulation of urban growth for the Madrid Region (Spain) based on Multi-Criteria Evaluation (MCE) techniques. The results suggest that the inclusion of the spatial perspective in the application of the SA is necessary, because it can modify the factors that have a decisive influence on the results.


An Agent-Based Assessment of Land Use and Ecosystem Changes in Traditional Agricultural Landscape of Portugal  [PDF]
Lilibeth A. Acosta, Mark D. A. Rounsevell, Martha Bakker, Ann Van Doorn, Montserrat Gómez-Delgado, Marc Delgado
Intelligent Information Management (IIM) , 2014, DOI: 10.4236/iim.2014.62008
Abstract:

This paper presents an assessment of land use changes and their impacts on the ecosystem in the Montado, a traditional agricultural landscape of Portugal in response to global environmental change. The assessment uses an agent-based model (ABM) of the adaptive decisions of farmers to simulate the influence on future land use patterns of socio-economic attributes such as social relationships and farmer reliance on subsidies and biophysical constraints. The application and development of the ABM are supported empirically using three categories of input data: 1) farmer types based on a cluster analysis of socio-economic attributes; 2) agricultural suitability based on regression analysis of historical land use maps and biophysical attributes; and 3) future trends in the economic and climatic environments based on the A1fi scenario of the Intergovernmental Panel on Climate Change. Model sensitivity and uncertainty analyses are carried out prior to the scenario analysis in order to verify the absence of systematic errors in the model structure. The results of the scenario analysis show that the area of Montado declines significantly by 2050, but it remains the dominant land use in the case study area, indicating some resilience to change. An important policy challenge arising from this assessment is how to encourage next generation of innovative farmers to conserve this traditional landscape for social and ecological values.

Modelling the hydrological behaviour of a coffee agroforestry basin in Costa Rica
F. Gómez-Delgado,O. Roupsard,R. Moussa,G. le Maire
Hydrology and Earth System Sciences Discussions , 2010, DOI: 10.5194/hessd-7-3015-2010
Abstract: The profitability of hydropower in Costa Rica is affected by soil erosion and sedimentation in dam reservoirs, which are in turn influenced by land use, infiltration and aquifer interactions with surface water. In order to foster the provision and payment of Hydrological Environmental Services (HES), a quantitative assessment of the impact of specific land uses on the functioning of drainage-basins is required. The present paper aims to study the water balance partitioning in a volcanic coffee agroforestry micro-basin (1 km2, steep slopes) in Costa Rica, as a first step towards evaluating sediment or contaminant loads. The main hydrological processes were monitored during one year, using flume, eddy-covariance flux tower, soil water profiles and piezometers. A new Hydro-SVAT lumped model is proposed, that balances SVAT (Soil Vegetation Atmosphere Transfer) and basin-reservoir routines. The purpose of such a coupling was to achieve a trade-off between the expected performance of ecophysiological and hydrological models, which are often employed separately and at different spatial scales, either the plot or the basin. The calibration of the model to perform streamflow yielded a NS coefficient equal to 0.80, while the validation of the water balance partitioning was consistent with the independent measurements of actual evapotranspiration (R2=0.79, energy balance closed independently), soil water content (R2=0.49) and water table level (R2=0.90). An uncertainty analysis showed that the streamflow modelling was precise for nearly every time step, while a sensitivity analysis revealed which parameters mostly affected model precision, depending on the season. It was observed that 64% of the incident rainfall R flowed out of the basin as streamflow, 25% as evapotranspiration and the remaining 11% was attributed to deep percolation. The model indicated an interception loss equal to 4% of R, a surface runoff of 5% and an infiltration component of 91%. The modelled streamflow was constituted by 63% of baseflow originating from the aquifer, 29% of subsurface non-saturated runoff and 8% of surface runoff. Given the low surface runoff observed under the current physical conditions (andisol) and management practices (no tillage, planted trees, bare soil kept by weeding), this agroforestry system on a volcanic soil demonstrated potential to provide valuable HES, such as a reduced superficial displacement-capacity for fertilizers, pesticides and sediments, as well as a streamflow regulation function provided by the highly efficient mechanisms of aquifer recharge and di
Modelling the hydrological behaviour of a coffee agroforestry basin in Costa Rica
F. Gómez-Delgado, O. Roupsard, G. le Maire, S. Taugourdeau, A. Pérez, M. van Oijen, P. Vaast, B. Rapidel, J. M. Harmand, M. Voltz, J. M. Bonnefond, P. Imbach,R. Moussa
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2011,
Abstract: The profitability of hydropower in Costa Rica is affected by soil erosion and sedimentation in dam reservoirs, which are in turn influenced by land use, infiltration and aquifer interactions with surface water. In order to foster the provision and payment for Hydrological Environmental Services (HES), a quantitative assessment of the impact of specific land uses on the functioning of drainage-basins is required. The present paper aims to study the water balance partitioning in a volcanic coffee agroforestry micro-basin (1 km2, steep slopes) in Costa Rica, as a first step towards evaluating sediment or contaminant loads. The main hydrological processes were monitored during one year, using flume, eddy-covariance flux tower, soil water profiles and piezometers. A new Hydro-SVAT lumped model is proposed, that balances SVAT (Soil Vegetation Atmosphere Transfer) and basin-reservoir routines. The purpose of such a coupling was to achieve a trade-off between the expected performance of ecophysiological and hydrological models, which are often employed separately and at different spatial scales, either the plot or the basin. The calibration of the model to perform streamflow yielded a Nash-Sutcliffe (NS) coefficient equal to 0.89 for the year 2009, while the validation of the water balance partitioning was consistent with the independent measurements of actual evapotranspiration (R2 = 0.79, energy balance closed independently), soil water content (R2 = 0.35) and water table level (R2 = 0.84). Eight months of data from 2010 were used to validate modelled streamflow, resulting in a NS = 0.75. An uncertainty analysis showed that the streamflow modelling was precise for nearly every time step, while a sensitivity analysis revealed which parameters mostly affected model precision, depending on the season. It was observed that 64% of the incident rainfall R flowed out of the basin as streamflow and 25% as evapotranspiration, while the remaining 11% is probably explained by deep percolation, measurement errors and/or inter-annual changes in soil and aquifer water stocks. The model indicated an interception loss equal to 4% of R, a surface runoff of 4% and an infiltration component of 92%. The modelled streamflow was constituted by 87% of baseflow originating from the aquifer, 7% of subsurface non-saturated runoff and 6% of surface runoff. Given the low surface runoff observed under the current physical conditions (andisol) and management practices (no tillage, planted trees, bare soil kept by weeding), this agroforestry system on a volcanic soil demonstrated potential to provide valuable HES, such as a reduced superficial displacement-capacity for fertilizers, pesticides and sediments, as well as a streamflow regulation function provided by the highly efficient mechanisms of aquifer recharge and discharge. The proposed combination of experimentation and modelling across ecophysiological and hydrological approaches proved to be useful to account for the behaviou
Performance Comparison among Trained Judges and Panels for the Evaluation of “Cuajada” Type Fresh Cheese in Two Regions from Oaxaca in México  [PDF]
Lorena Guadalupe Ramón Canul, Emmanuel de Jesús Ramírez Rivera, Rodrigo Santiago Cabrera, Fátima Karina Delgado Vidal, José Manuel Juárez Barrientos, María Hernández Cervantes, Juliana López Velázquez, Tania Gómez Alvarado
Food and Nutrition Sciences (FNS) , 2011, DOI: 10.4236/fns.2011.210156
Abstract: Four “cuajada” type fresh cheeses were evaluated by two trained panels in different regions from Oaxaca in Mexico (Instituto Tecnológico de Comitancillo (ITC) and Universidad del Mar (UMAR)). Each panel was integrated by six judges. Analysis of variance (ANOVA) in conjunction with principal component analysis (PCA) and the Rv coefficient were used to identify similarities and consensus among trained judges and panels. The ANOVA results revealed that the judges from ITC performed significantly better (P < 0.05) in discrimination and repetitivity, while both panels showed a similar effect in discrimination. The PCA determined some similarities in the position of cheeses in the sensory space, while Rv revealed that judges and panels were consensual. In conclusion, statistical resources determined that both panels were discriminating and that similarities in the positioning of cheeses in the sensory space were found.
Estudio epidemiológico-molecular de un brote de tuberculosis en el hospital psiquiátrico de La Habana
Gómez Delgado,Ramón I.; Díaz Rodríguez,Raúl; García Acosta,Nelaine; Valdivia álvarez,José A.;
Revista Cubana de Higiene y Epidemiolog?-a , 2000,
Abstract: the increase of tuberculosis in cuba in the last years has been partially related to the ocurrence of institutional outbreaks, confirmed by the analysis of the polymorphism of restriction fragments. in the present paper, the increase of tuberculosis cases diagnosed in the period 1995-1998 among the patients of the psychiatric hospital of havana city was studied in order to know their possible epidemic character. it was observed that most of the patients were from wards located in a well defined area of the institution. 11 of the 14 strains analyzed had an identical restriction pattern. the molecular and convencito findings allowed to confirm the nature of the outbreak and to define the index case as well as the possible way of transmission. it was reaffirmed the value of the molecular techniques as a valuable instrument in the epidemiology of tuberculosis and their contribution to the local epidemiological control of this disease.
Estudio epidemiológico-molecular de un brote de tuberculosis en el hospital psiquiátrico de La Habana
Ramón I. Gómez Delgado,Raúl Díaz Rodríguez,Nelaine García Acosta,José A. Valdivia álvarez
Revista Cubana de Higiene y Epidemiología , 2000,
Abstract: El incremento de la tuberculosis en Cuba en los últimos a os ha estado parcialmente relacionado con la ocurrencia de brotes institucionales, confirmado por el análisis del polimorfismo de los fragmentos de restricción. En este trabajo se estudió, por métodos epidemiológicos convencionales y moleculares, el aumento de casos de tuberculosis diagnosticados en 1995-1998 entre los pacientes en el Hospital Psiquiátrico de La Habana para conocer su posible carácter epidémico. Se observó que la mayoría de los pacientes pertenecían a salas localizadas en un área bien definida de la institución. Tenían un patrón de restricción idéntico 11 de las 14 cepas analizadas. Los hallazgos moleculares y convencionales permitieron confirmar el carácter de brote y definir el caso índice y la posible vía de transmisión. Se reafirmó el valor de las técnicas moleculares como instrumento valioso en la epidemiología de la tuberculosis y su contribución al control epidemiológico local de esta enfermedad. The increase of tuberculosis in Cuba in the last years has been partially related to the ocurrence of institutional outbreaks, confirmed by the analysis of the polymorphism of restriction fragments. In the present paper, the increase of tuberculosis cases diagnosed in the period 1995-1998 among the patients of the Psychiatric hospital of Havana city was studied in order to know their possible epidemic character. It was observed that most of the patients were from wards located in a well defined area of the institution. 11 of the 14 strains analyzed had an identical restriction pattern. The molecular and convencito findings allowed to confirm the nature of the outbreak and to define the index case as well as the possible way of transmission. It was reaffirmed the value of the molecular techniques as a valuable instrument in the epidemiology of tuberculosis and their contribution to the local epidemiological control of this disease.
Fundamentos de criopreservación
ávila-Portillo,Luz Mabel; Madero,José I; López,Claudia; León,María Fernanda; Acosta,Lucía; Gómez,Claudia; Delgado,Lucy Gabriela; Gómez,Claudio;
Revista Colombiana de Obstetricia y Ginecología , 2006,
Abstract: the appropriate understanding of and applying cryopreservation to biological material is fundamental for laboratories and cell-banks. however, although protocols have been implemented for cryopreservation, ideal standards are still not being achieved or complied with in most cases. a suitable cryopreservation technique must be based on knowledge of a particular cell and/or tissue's physicochemical properties because cryopreservation is affected by different variables such as cellular permeability, osmotic inactive volume and a cell's surface/area relationship which varies according to the species, type and state of the cell to be frozen. plasmatic membrane structure and composition determine the main cellular events taking place during cryopreservation; a drop in temperature affects diffusion and osmosis through membranes and each cell manages its own biophysical profile interacting with different cellular cryoprotectors. cell viability and functionality can only be guaranteed by ensuring that an appropriate protocol is implemented and followed.
Factores asociados al consumo de frutas y verduras en Bucaramanga, Colombia
Gamboa Delgado,Edna Magaly; López Barbosa,Nahyr; Prada Gómez,Gloria Esperanza; Franco Cadena,José Tomás; Landínez Navarro,Ariel;
Archivos Latinoamericanos de Nutrición , 2010,
Abstract: the objective of this study was to determine associated factors to the consumption of fruit and vegetables (fv) in the adult population of each socioeconomic status (ses) in bucaramanga, colombia. we conducted a cross-sectional in a sample of 317 people and we measured socio-demographic, economic and anthropometric variables and dietary factors related to the purchase and consumption of fv. we made a survey, a 24-hour dietary recall and we did anthropometric measurements. portion sizes were estimated with a standardized set of utensils and food-photography atlas. frequencies, measures of central tendency and dispersion were established and logistic regression models were used for the bi and multivariate analysis. average consumption of fv was 162.6 g / day (188.5 g in high ses and 145.7 g in low ses, p= 0.056). on average 2 servings per day of fv (2.3 servings in high ses and 1.5 in low ses, p = 0.055). the prevalence of adequate intake of fv (more than 5 servings / day) was 8.6% (8.9% in high ses and 8.4% in low ses, p = 0.896). the associated factor to consumption of fv was bmi > 25 (or: 0.31, ci (95%): 0.11-0.89, p = 0.030), adjusted for occupation, income, ses, and number of family members. fv consumption is low; excess weight is the only variable associated to no-consumption of five or more servings; causes: cost to the consumption of fruit and flavor in the case of vegetables.
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