37 research outputs found

    Relación entre la perimetría automatizada convencional y la topografía papilar realizada con el tomógrafo Heidelberg

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    espanolObjetivo: Determinar las correlaciones entre los parametros de la cabeza del nervio optico (CNO) obtenidos mediante el laser confocal de barrido (HRT), y los resultados de la perimetria automatizada convencional (PA) en sujetos normales, hipertensos oculares (HTO), sospechosos de glaucoma y glaucomatosos. Metodos: Cuatrocientos veintitres ojos fueron incluidos en el estudio y clasificados segun la presion intraocular basal, morfologia papilar y los resultados de la PA en 4 grupos: 87 normales, 192 hipertensos oculares, 70 sospechosos de glaucoma y 74 glaucomatosos. En los diferentes grupos diagnosticos, se calcularon los coeficientes de correlacion de Pearson entre los parametros de la CNO y la desviacion media (DM), la desviacion estandar de la media (DSM), el numero de puntos alterados en cada cuadrante del campo visual (superior-nasal, inferior-nasal, superior-temporal e inferior-temporal), el numero de puntos alterados segun los niveles de probabilidad y los valores umbral en cada punto de la PA. Resultados: En el grupo normal y de hipertensos oculares, se encontraron pocas correlaciones debiles entre los parametros del HRT y los resultados de la PA. La fuerza y el numero de correlaciones significativas aumentaron en el grupo de sospechosos de glaucoma. En el grupo de glaucomas, las correlaciones fueron mas fuertes, especialmente entre los cocientes excavacion/disco y anillo/disco con la DM (r=0,479) y entre el area de anillo con la DSM (r=0,444). Conclusiones: Se encontraron correlaciones debiles o moderadas entre algunos parametros de la CNO medidos con el HRT y los resultados de la PA, en el grupo de glaucomas. EnglishPurpose: To determine the correlations between optic nerve head (ONH) parameters measured with the Heidelberg Retina Tomograph (HRT), and the main outcomes of standard automated perimetry (SAP) in normal, ocular hypertensive, glaucoma suspects and glaucomatous subjects. Methods: Four hundred and twenty-three patients were enrolled in the study and classified into four groups depending on baseline intraocular pressure, optic nerve head morphology, and SAP results: 87 normal eyes, 192 ocular hypertensive eyes, 70 glaucoma suspects and 74 glaucomatous eyes. In the different diagnostic groups, Pearson's correlation coefficients were calculated between ONH parameters and mean deviation, pattern standard deviation (PSD), number of altered points in each quadrant of the visual field (superior-nasal, inferior-nasal, superior-temporal and inferior-temporal), number of points altered at different probability levels, and threshold values at each point of SAP. Results: In the normal and ocular hypertensive groups, only a few weak correlations were found between HRT and SAP parameters. The strength and number of significant correlations increased in the suspected glaucoma group. The glaucoma group had the strongest correlations, particularly between cup/disc ratio and rim/disc ratio with MD (r=0.479) and between rim area and PSD (r=0.444). Conclusions: Weak to moderate correlations were found between some ONH parameters obtained with the HRT and SAP results in the glaucoma grou

    Novel heuristics for cell radius determination in WCDMA systems and their application to strategic planning studies

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    We propose and compare three novel heuristics for the calculation of the optimal cell radius in mobile networks based on Wideband Code Division Multiple Access (WCDMA) technology. The proposed heuristics solve the problem of the load assignment and cellular radius calculation. We have tested our approaches with experiments in multiservices scenarios showing that the proposed heuristics maximize the cell radius, providing the optimum load factor assignment. The main application of these algorithms is strategic planning studies, where an estimation of the number of Nodes B of the mobile operator, at a national level, is required for economic analysis. In this case due to the large number of different scenarios considered (cities, towns, and open areas) other methods than simulation need to be considered. As far as we know, there is no other similar method in the literature and therefore these heuristics may represent a novelty in strategic network planning studies. The proposed heuristics are implemented in a strategic planning software tool and an example of their application for a case in Spain is presented. The proposed heuristics are used for telecommunications regulatory studies in several countries

    Biogeographical patterns in the diet of an opportunistic predator: the red fox Vulpes vulpes in the Iberian Peninsula

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    Biogeographical diversity is central to the trophic ecology of predators. Understanding the biogeographical trophic patterns of generalist predators, such as the red fox Vulpes vulpes, is particularly challenging because of their wide distributions, broad trophic spectra and high ecological plasticity, which often generate conflicts with humans. We reviewed 55 studies from the Iberian Peninsula concerning the diet of the red fox to describe its trophic patterns from a biogeographical perspective. We considered the frequency of occurrence of seven food groups and characterized each study site according to environmental variables. We tested relationships between geographical variables and each food group independently, and assessed the consumption of lagomorphs in relation to the other food groups. We also tested the relationships between trophic diversity, the main food groups, latitude and altitude, and finally investigated changes in the consumption of all food groups in relation to habitat type and seasonality. We found a latitudinal pattern in the diet of the red fox, which was characterized by a greater consumption of lagomorphs and invertebrates in southern areas, and a higher intake of small mammals and fruits/seeds in northern regions. Additionally, the consumption of invertebrates increased from east to west, while fruit/seed consumption increased from west to east. Consumption of lagomorphs decreased, and of small mammals increased, with altitude. Trophic diversity was not associated with geographical variables. The intake of lagomorphs and small mammals was greatest in Mediterranean scrub and forest, respectively. Reptiles and invertebrates were consumed mostly during summer; fruits/seeds in autumn. Iberian red foxes show variation in their feeding habits associated with environmental variables, which are in turn associated with the availability of their main prey. Foxes select rabbits where they are abundant, and feed on small mammals and fruits/seeds where lagomorphs are scarce.M. Delibes-Mateos currently holds a Juande la Cierva research contract awarded by the Ministerio de Ciencia e Innovación and the European Social Fund. C. Ferreira was supported by a PhD grant (Ref. SFRH/BD/22084/2005) funded by the Fundação para a Ciência e Tecnologia of the Ministério da Ciência, Tecnologia e Ensino Superior, Portuguese government. Financial support for the study was provided by the Spanish MICINN Project CGL2009-10741 from Spanish Plan Nacional de I+D and FEDER funds.Peer Reviewe

    An optimization on pictogram identification for the road-sign recognition task using svms

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    Pattern recognition methods are used in the final stage of a traffic sign detection and recognition system, where the main objective is to categorize a detected sign. Support vector machines have been reported as a good method to achieve this main target due to their ability to provide good accuracy as well as being sparse methods. Nevertheless, for complete data sets of traffic signs the number of operations needed in the test phase is still large, whereas the accuracy needs to be improved. The objectives of this work are to propose pre-processing methods and improvements in support vector machines to increase the accuracy achieved while the number of support vectors, and thus the number of operations needed in the test phase, is reduced. Results show that with the proposed methods the accuracy is increased 3?5% with a reduction in the number of support vectors of 50?70%

    Visión actual del cólera

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    El cólera de manifiesta con síntomas diarreicos y deshidratación causada por el Vibrio cholerae con los serotipos: O1 y O139. En su forma más grave puede producir una intensa deshidratación y shock hipovolémico causando la muerte.Aunque es originario del río Ganges, la última pandemia surgió en Indonesia y se ha propagado por Asia, África y América.Aun desconociéndose con precisión el número anual de casos, se estima en tres millones con una mortalidad de 100.000 personas.La vacunación y las medidas concretas como la potabilización del agua en sitios puntuales han surtido su efecto, pero para la solución a largo plazo, se necesitaría provisiones permanentes de agua potabilizada y saneamiento; mejora del sistema de salud y reducción general de la pobreza.Cholera disease showes diarrohea symtoms and dehydration caused by Vibrio Cholerae, which Serotype are: O1 and O139 .Although, it´s from Ganges River, the last pandemic arose in Indonesia and it has been spreaded in Asia, Africa and America.It´s calculated three millions of Clinical cases with 100.000 dead people, but the number of the cases hasn´t yet known.Vacinnation and concrete measures as: water purification in determinated places, have been partially successed but it should be needed permanente provisions of healthy driniking water, improvising health system and general reduction of poverty

    Competitive Asymmetries in the Use of Supplementary Food by the Endangered Iberian Lynx (Lynx pardinus)

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    Background: As a conservation tool, supplementary feeding programs may be directed to specific individuals or sectors of the target population whose productivity or survival is thought to be limited by food scarcity. However, the use of supplemental food by different sex and age classes has received little attention. We studied individual variation in the access of the endangered Iberian lynx (Lynx pardinus) to supplementary food. Methodology/Principal Findings: From 5349 pictures taken with automatic cameras placed in 25 feeding stations, we identified 28 individuals whose sex and age were known. All individuals known to live in areas subjected to supplementation regularly visited feeding stations. Food consumption was not proportional to expected variations in energy demand within sex and age classes. Food consumption by males was higher than by females, and increased with age, in agreement with a despotic distribution. Food consumption also increased with lynx body mass, and this pattern held for individuals sharing the same breeding territories. The access of inferior competitors increased with the number of feeding stations available within lynx territories. Conclusions/Significance: All lynx exposed to food supplementation made a regular use of extra food but individuals predicted to be competitively dominant visited stations more frequently than subordinates of the same breeding territory. Our results suggest that insufficient provision of supplementary food could restrict the access of juveniles, or even adult females, to feeding stations. Limited consumption by these target individuals may compromise the efficiency of the supplementary feeding programme at the population level, in endangered species that, as the Iberian lynx, exhibit marked sexual dimorphism in body size.Peer reviewe

    Factores determinantes de la educación financiera en los jóvenes pre-universitarios

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    [ES] La crisis económica y la globalización financiera han impulsado la necesidad de conocer y mejorar la educación financiera en la sociedad. Este trabajo estudia la educación financiera de los jóvenes de Castilla y León a través de encuestas realizadas a 1.253 estudiantes. Los resultados muestran que existen determinados factores socioeducativos que pueden influir en un mayor nivel de educación financiera. En términos generales, este estudio encuentra que la competencia financiera de los estudiantes, a partir de los resultados (tasa de aciertos) en un cuestionario, difiere en función del tipo de estudios, la formación previa en materia económica, la titularidad del centro y otras variables de índole personal. Por otro lado, en contraposición a la mayoría de trabajos previos, no se observa brecha de género, indicando que no es este un factor condicionante en la educación financiera, al menos cuando el resto de determinantes de los individuos son similares. Estos resultados son de interés para la comunidad educativa pues pueden orientar la formación de los estudiantes y diseñar las necesidades educativas específicas en materia financiera considerando tanto la tipología de centros como las características de los individuos

    Agriculture intensity and landscape configuration influence the spatial use of wildcats across Europe

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    Land use intensification is increasing worldwide and affects wildlife movements, particularly of specialist carnivores. Resource availability and anthropogenic activities drive the extent and shape of home range size. Wildlife may respond to decreased resource availability under intensification scenarios by increasing their home ranges; however they may be less affected when inhabiting sustainable agricultural landscapes. We investigate whether agricultural practices and landscape configuration influence the spatial behaviour of wildcats, a medium-sized specialist carnivore inhabiting landscapes with different degrees of agricultural presence across Europe. We focus on the effect of the proportions of high impact and low impact agriculture, forest integrity and forest edge density on wildcat home range size. We found that wildcat home range increased along with the proportion of high impact agriculture and the forest integrity, whereas it decreased when forest edge density increased. Forest edge density buffered the detrimental effects caused by high impact agriculture. To enhance the long term conservation of wildcats in Europe it is crucial to protect the sustainable mosaic-structured landscapes and prevent its conversion to homogenous intensified agricultural landscapes.HRV is beneficiary of a PhD scholarship “Severo Ochoa” from the Regional Government of Principality of Asturias. JVLB was supported by a Ramón y Cajal research contract (RYC-2015-18932) from the Spanish Ministry of Economy, Industry and Competitiveness. F. Díaz-Ruiz was supported by a postdoctoral contract from the University of Málaga (I Plan Propio de Investigación y Transferencia, call 2020).Peer reviewe
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