Volumen 4 No. 1 (2013)
Permanent URI for this collectionhttps://dspace-test.ucuenca.edu.ec/handle/123456789/5378
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Item Comparative analysis of 1-D river flow models applied in a quasi 2-D approach for floodplain inundation prediction(Universidad de Cuenca, 2013-06) Villazón, Mauricio F.; Timbe, Luis M.; Willems, Patrick; Universidad de Cuenca; Dirección de Investigación de la Universidad de Cuenca; DIUCA comparative analysis was performed of three 1-D river hydrodynamic models (Mike 11, InfoWorks-RS and HEC-RAS) in a quasi 2-D setting. The study area was schematized either as a network of fictitious river branches or as storage areas. The models were run on a reduced area of the Dender River basin in Belgium, respectively for three historical flood events and eight synthetic events with a return period between 1 and 1000 years. The performance of the models were tested comparing simulated discharge, water level, inundation volume and inundated area. Results show that the three models and the two approaches used for the presentation of the floodplain lead to very similar results with a root mean square error of around 6 cm for the peak river levels and 2% for the river discharges. Despite the high accuracy of the water levels in the main river, inundation levels inside the floodplains have root mean square errors of around 25 cm during flood conditions.Item Modeling the unsaturated flow associated with a border irrigation event on an alfalfa plot(Universidad de Cuenca, 2013-06) Vázquez, R. F.; Isidoro, D.; Sayah, B.; Universidad de Cuenca; DIUC; Dirección de Investigación de la Universidad de CuencaHYDRUS-1D, a one dimensional water movement and solute transport model, was applied to analyze a border irrigation event in an alfalfa plot located in the irrigation district of "La Violada" (Spain). The research encompassed monitoring of the irrigation event, the setting-up of the numerical model, model calibration and evaluation, and sensitivity analysis of the van Genuchten-Mualem parameters. Both the model predictions and field measurements clearly indicated that the soil water content was high during and following the irrigation event. The model even predicted a small evapotranspiration decrease induced by water logging and a significant contribution of capillary rise subsequently the water table rise in the adjacent plot caused by an irrigation event prior to the monitored event in the study plot. The research revealed the need for (i) the improvement of the schematization of the soil profile and the better experimental definition of key model parameters; and (ii) the derivation of more accurate data series for respectively the upper and lower boundary conditionsItem El detalle en la arquitectura construida del Illinois Institute of Technology de Mies van der Rohe(Universidad de Cuenca, 2013-06) Hermida Palacios, María Augusta; Universidad de Cuenca; DIUC; Dirección de Investigación de la Universidad de CuencaThis article explains the process by which Ludwig Mies van der Rohe approximates the most "beautiful", abstract and universal structural and constructive solution in the buildings of the Illinois Institute of Technology. Mies van der Rohe works with steel but when the material is not available or the conditions are not appropriate, he explores, without protest and with the same depth, other structural materials and or systems. Mies always tries to define satisfactory solutions, because for him projects’ structural clarity not only means identifying the most suitable structure, but and not at the least deepening and optimizing the characteristic order of the structure. When analyzing the structural systems and its relation with the used materials, we discover that for him the most important aspect is the visual structure of the objects and the gradual evolution towards more abstract solutions. Observation of the architectural details reveals that the constructive solution of a project is a ‘consequence’ of the previous and the ‘cause’of the following.Item Desarrollo de la composición óptima del pan de dulce y de sal utilizando ingredientes tradicionales(Universidad de Cuenca, 2013-06) Pinos Vélez, Verónica Patricia; Alvarez P., Ruth Cecilia; Tripaldi Cappelletti, Piercósimo; DIUC; Dirección de Investigación de la Universidad de Cuenca; Universidad de CuencaMultivartiate statistics were applied to develop two types of bread with non-classical ingredients, respectively sweet and salty bread. Several combinations of eleven variable gradients, such as zambo seeds, peanuts, quinoa, brown sugar and banana flour, were mixed in such a way that the acceptance level of both breads was minimum 0,97 out of 1 points. The limits and condition of the ingredients, and the procedures were determined based on theoretical considerations and preliminary experimental results. In an initial phase the factorial model of Plackett-Burman was applied enabling the reduction of experiments from 2059 to 14, for each type of bread. Every step of the process was evaluated with an expert panel adopting surveys of acceptation of organoleptic characteristics, cost and the public willingness to buy. The relevant ingredients were respectively for the sweet bread mermelade of figs and nuts, while peanuts for the salt bread. In a subsequent phase the significant ingredients were optimized to maximize the composition of both bread types. In the evaluation by the public the sweet bread scored and acceptance level of 90%, whereas the salt bread gained a score of 78%.Item Detección por medio de la técnica RT-PCR de los virus CymMV y ORSV en el cultivo de orquídeas(Universidad de Cuenca, 2013-06) Villena Ochoa, Paulina Germania; Universidad de Cuenca; DIUC; Dirección de Investigación de la Universidad de CuencaCymbidium mosaic potexvirus (CymMV) and Odontoglossum ringspot tobamovirus (ORSV) are the most prevalent pathogens affecting worldwide the cultivation of orchids, causing incalculable losses in revenue. They reduce growth vigor and quality, and what is most problematic they are not curable once infected. A diagnostic method, based on the chain reaction reverse transcription polymerase (RT-PCR), was developed to detect both viruses. The method consists of the extraction of nucleic acids of infected plants and applying the RT-PCT method, similar to the ELISA (enzyme linked immuno-sorbent assay) virus indexing technique. Leave, flower and bulb samples of different species of in vitro reproduced healthy and affected Cattleya orchids were analyzed in the molecular biotechnology laboratory of Concept Blue Corporation in Guayaquil, Ecuador. The comparative analysis revealed that RT-PCR is more effective in the detection of CymMV and ORSV viruses than the ELISA technique. Furthermore the study revealed that CymMV was preferentially detected in leaves, flowers and small bulbs, while the ORSV virus was only detected in leaves and bulbs. The latter permitted to describe the symptoms associated to each type of infection and the propagation of virus-free plants applying the meristem-tip culture.Item Efecto de suplementos de zinc en la incidencia de caries y en la concentración de Inmunoglobulinas a salivales en niños escolares de talla baja(Universidad de Cuenca, 2013-06) Parra Coronel, Janeth; Astudillo, Diana; Sempértegui, Fernando; Universidad de Cuenca; Dirección de Investigación de la Universidad de Cuenca; DIUCYoung children in Ecuador show high prevalence of chronic zinc deficiency, associated with a decline in cellular and humoral immunity, and increased risk of tooth decay. The research reported in this paper presents the effect of the daily consumption of 10 mg zinc sulfate versus the control group receiving a solution with an inactive substance during 42 weeks, on respectively the children’s weight, height, the immunoglobulin A (IgA) concentration in saliva, the plasma concentrations of zinc, and the indices of Klein and Palmer (DMFT and DMFS). In the survey special attention was given to the detection of early stage tooth decay, also called incipient decay. Parallel, information about the children’s hygiene and living condition was collected using structured questionnaires. Statistical analysis of the collected data revealed that DMFS is less and the final concentration of plasma zinc higher in the experimental group of children receiving daily a zinc supplement (17,30 ± 9,55 vs. 20,03 ± 10,74; p = 0,032; 123 ± 24,29 μg dl-1 vs. 105,57 ± 15,75 μg dl-1; p < 0,001).Item Factores de riesgo asociados a la osteoporosis posmenopáusica: estudio de casos de los Hospitales Vicente Corral y José Carrasco(Universidad de Cuenca, 2013-06) Guevara, Sergio; Feicán, Astrid; Ochoa, María del Carmen; Arévalo, Carlos; Aguirre, María EugeniaThe purpose of the study presented herein is the assessment of the statistical relation between postmenopausal osteoporosis (PO) and the following risk factors: low body mass index (BMI), low calcium diet, delayed menarche, early menopause, sedentary lifestyle and socioeconomic status. The research involved the screening of 112 postmenopausal women with osteoporosis and 112 control patients, aged 50 to 65, patients belonging respectively to the Hospitals Vicente Corral and José Carrasco, in Cuenca, Ecuador. A questionnaire addressing calcium-intake, socio-demographic, reproductive and lifestyle-related risk factors was employed previously to bone mineral density and other physical measurements using validated instruments. In addition to the calculation of the mean,