Central University of Ecuador

About: Central University of Ecuador is a education organization based out in Quito, Ecuador. It is known for research contribution in the topics: Population & Medicine. The organization has 2220 authors who have published 1910 publications receiving 15052 citations.

Characterization of River Sediments in Loja-Ecuador

Abstract: This research's main objective is to delineate areas with a high concentration of "pollutant" elements that imply a risk for the ecosystem and inhabitants' health in the Cordillera Real, south of Ecuador. To this end, a survey was carried out applying statistical analysis of the data. Specifically, the method of ordinary Kriging and Lepeltier is used to sort the data in populations according to their concentration. Previously, the information was compared with national (TULAS) and international regulations (Environmental Canada). These metals' spatial distribution is shown in concentration maps for each element (Hg, Pb, Zn, As, and Cu), where the potential villages exposed to these anomalies are displayed. In this sense, the samples' chemical digestion was conducted to quantify the atomic emission technique's before-mentioned pollutants' concentration. It was also correlated with geology, mineral occurrences, and metallogeny evidence to conclude that Pb and Zn anomalies are related to San Lucas granodiorite's intrusion, whereas Cu and Hg with local mineralization of sulfides, and as may be with domestic and industrial discharges. Finally, even though the anomalous concentrations of metallic elements were found to be characteristic of the lithology, cautions should be taken to safeguard the health of people and agriculture because there is evidence of elements such as As and Hg bioaccumulation in species that are part of the food chain.

Comparación entre las técnicas de Ricketts y McNamara para la determinación de la posición del maxilar y la mandíbula en jóvenes del Ecuador

Abstract: RESUMEN: Los análisis cefalométricos, a partir de una radiografía lateral de cráneo, son amplios y variados considerando tanto los patrones funcionales co m los de estética facial. Entre las técnicas de medición en cefalometría, Ricketts y de McNamara son ampliamente utilizados; ambas le entregan importancia a determinar la posición del maxilar y de la mandíbula con diferentes relacione s esqueletales. El objetivo de esta investigación es comparar ambas técnicas en una población joven de Ecuador; se realizó un análisis de conco rdancia utilizando el índice kappa de Cohen entre los resultados de las mediciones correspondientes a 44 radiografías cefálicas lateral es de suj tos jóvenes entre 18 y 27 años de edad, de ambos sexos. En relación a la posición maxilar, el 56,82 % (IC 95 %: 42,18 % 71,45 %) coinciden en el diagnóstico de protrusión maxilar; el índice de concordancia kappa de Cohen fue de 0,599 (IC 95 %: 0,354 – 0,854) con un valor p<0,05. En relación a la posición mandibular, el 50,0 % (IC 95 %: 35,23 % 64,77 %) coinciden en el diagnóstico de retrusión m andibular; el índice kappa de Cohen fue de 0,460 (IC 95 % 0,229 – 0,691) con un valor p<0,05. Se concluye que, a pesar de manejar puntos d e refere cia cefalométricos diferentes, las dos técnicas de medición cráneo-facial son útiles para el estudio de posición de maxila y mandíb ula. Existen diferencias entre algunos analisis de ambos estudios que pueden incidir en la selección terapéutica de potenciales pacientes.

Serum Concentrations of Essential Trace and Toxic Elements in Healthy and Disease-Affected Dogs

Abstract: This study was designed (i) to establish reference ranges for the essential trace element and background levels of toxic element exposure in the healthy/normal dog population, and (ii) to evaluate whether trace element concentrations vary in dogs suffering from different pathologies Blood serum samples were collected from 187 healthy and diseased dogs at the Veterinary Teaching Hospital, Faculty of Veterinary Medicine, University of Santiago de Compostela (northwest Spain) The samples were acid digested, and the concentrations of trace elements (Co, Cr, Cu, Fe, Mn, Mo, Ni, Se and Zn) and toxic elements (As, Cd, Hg and Pb) were determined by inductively coupled plasma-mass spectrometry (ICP-MS) This enabled us to establish reference ranges for the essential trace elements and the level of toxic element exposure in dogs, and to identify several clinical situations associated with variations in trace elements in serum Relative to concentrations in healthy control dogs, statistically significant differences were observed in the concentrations of Cu (significantly higher in hepatic, inflammatory/infectious and oncological categories), Mo (significantly higher in renal category), Se (significantly lower in gastrointestinal category) and Zn (significantly lower in gastrointestinal, inflammatory/infectious and renal categories) Trace element concentrations can be a cause or consequence of disease, and the study findings indicate that trace element determination in serum provides useful information on the pathogenesis of certain diseases Further research on the serum concentrations of trace elements, particularly in relation to other biochemical parameters and diagnostic tools, may provide valuable information for the diagnosis of diseases in dogs and the disease prognosis

Criodesecación atmosférica de papa (Solanum tuberosum)

Abstract: Mediante la aplicacion del proceso conocido como crio-desecacion atmosferica (CDA) usando temperaturas bajas y cloruro de calcio o silicagel como agentes higroscopicos, se deshidrataron dos variedades de papa, Gabriela y Chaucha. A las papas se les realizo tres diferentes pretratamientos. Con los datos obtenidos se calcularon: (i) los valores de los coeficientes de transferencia superficial de masa (de 61.77 a 148.55 kg·m-2·s-1), (ii) de calor (de 5.75 a 11.22 W·m-2·°C-1), (iii) el numero adimensional (de 1.03 a 3.98), (iv) el tiempo de secado (de 200.00 a 303.26 h), y (v) el indice de rehidratacion (de 1.7 a 2.7). Ademas, se evaluo que mecanismo de transferencia de masa controla la CDA, se analizo los cambios de color del producto durante tres etapas del proceso, empleando el indice de amarillez, y se evaluaron las propiedades microbiologicas de las papas crio-desecadas atmosfericamente. Se concluye que el secado de rodajas de papa por CDA permite eliminar el crecimiento microbiologico y las reacciones quimicas, pero es necesario realizar pretratamientos para evitar el pardamiento.

Machine learning methods from group to crowd behaviour analysis

Abstract: The human behaviour analysis has been a subject of study in various fields of science (eg sociology, psychology, computer science) Specifically, the automated understanding of the behaviour of both individuals and groups remains a very challenging problem from the sensor systems to artificial intelligence techniques Being aware of the extent of the topic, the objective of this paper is to review the state of the art focusing on machine learning techniques and computer vision as sensor system to the artificial intelligence techniques Moreover, a lack of review comparing the level of abstraction in terms of activities duration is found in the literature In this paper, a review of the methods and techniques based on machine learning to classify group behaviour in sequence of images is presented The review take into account the different levels of understanding and the number of people in the group