4,812 research outputs found

    Land cover mapping at very high resolution with rotation equivariant CNNs: towards small yet accurate models

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    In remote sensing images, the absolute orientation of objects is arbitrary. Depending on an object's orientation and on a sensor's flight path, objects of the same semantic class can be observed in different orientations in the same image. Equivariance to rotation, in this context understood as responding with a rotated semantic label map when subject to a rotation of the input image, is therefore a very desirable feature, in particular for high capacity models, such as Convolutional Neural Networks (CNNs). If rotation equivariance is encoded in the network, the model is confronted with a simpler task and does not need to learn specific (and redundant) weights to address rotated versions of the same object class. In this work we propose a CNN architecture called Rotation Equivariant Vector Field Network (RotEqNet) to encode rotation equivariance in the network itself. By using rotating convolutions as building blocks and passing only the the values corresponding to the maximally activating orientation throughout the network in the form of orientation encoding vector fields, RotEqNet treats rotated versions of the same object with the same filter bank and therefore achieves state-of-the-art performances even when using very small architectures trained from scratch. We test RotEqNet in two challenging sub-decimeter resolution semantic labeling problems, and show that we can perform better than a standard CNN while requiring one order of magnitude less parameters

    Association of frailty status in older adults with immunological endocrine and oxidative stress biomarkers

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    Programa Oficial de Doutoramento en Bioloxía Celular e Molecular . 5004V01[Resumen] La fragilidad es un síndrome geriátrico multidimensional caracterizado por una pérdida de homeostasis y un incremento de la vulnerabilidad. Actualmente, la identificación de la fragilidad se basa en características fenotípicas. Dada su reversibilidad, la identificación de la fragilidad mediante biomarcadores sería primordial para posibilitar una detección más temprana y precisa de los individuos frágiles. Debido a esto, el objetivo de este estudio fue investigar la posible asociación de diferentes biomarcadores con la fragilidad en personas mayores. Para ello, se llevó a cabo un estudio transversal en una población de mayores de 65 años, clasificados de acuerdo a su estado de fragilidad, determinando un conjunto de biomarcadores relacionados con la activación inmune y la inflamación, el sistema endocrino y el estrés oxidativo. Los resultados obtenidos mostraron diferencias significativas en los niveles de varios biomarcadores inmunológicos y el cortisol entre individuos frágiles y no frágiles, pero no se encontró asociación alguna entre los biomarcadores de estrés oxidativo y el estado de fragilidad. Los datos presentados en este trabajo apoyan la hipótesis de que el estado de fragilidad en personas mayores está relacionado con la estimulación inmune y la inflamación, así como con la desregulación del eje hipotalámico-pituitario-adrenal dependiente de la edad.[Resumo] A fraxilidade é un síndrome xeriátrico multidimensional caracterizado por unha pérdida de homeostase e un incremento da vulnerabilidade. Actualmente, a identificación da fraxilidade basease en características fenotípicas Dada a súa reversibilidade, a identificación da fraxilidade mediante biomarcadores sería primordial para posibilitar unha detección máis temperá e precisa dos individuos fráxiles. Debido a isto, o obxectivo deste estudo foi investigar a posible asociación de diversos biomarcadores coa fraxilidade en persoas maiores. Para iso, levóuse a cabo un estudo transversal nunha poboación de maiores de 65 anos, clasificados de acordo ao seu estado de fraxilidade, determinando un conxunto de biomarcadores relacionados coa activación inmune e a inflamación, o sistema endócrino e o estrés oxidativo. Os resultados obtidos amosaron diferencias significativas nos niveis de varios biomarcadores inmunolóxicos e o cortisol entre individuos fráxiles e non fráxiles, pero non se atopou asociación algunha entre os biomarcadores de estrés oxidativo e o estado de fraxilidade. Os datos presentados neste traballo apoian a hipótese de que o estado de fraxilidade en persoas maiores está relacionado coa estimulación inmune e a inflamación, así como coa desregulación do eixo hipotalámico-pituitario-adrenal dependente da idade.[Abstract] Frailty is a multidimensional geriatric syndrome of loss of reserves and increased vulnerability to stressors. Currently, frailty identification is based on phenotypic characteristics. Due to the well-known reversibility of frailty, early identification is crucial. Biomarkers can be useful tools for the early and accurate detection of frail individuals. Thus, the main objective of this study was to investigate the possible relationship of different biomarkers with frailty in older adults. To that aim, a cross-sectional study was conducted in a population of older adults (aged 65 years and over) classified according to their frailty status, determining a set of biomarkers related to immune activation and inflammation, to endocrine system, and to oxidative stress. Results obtained revealed significant differences in the levels of several immunological biomarkers and cortisol between frail and non-frail individuals, but no association was found between any oxidative stress biomarker and frailty status Data presented in this study provide support to the hypothesis that frailty status in older adults is associated with an additional degree of immune stimulation and inflammation, and with agerelated hypothalamic pituitary adrenal axis dysregulation

    Buscando áreas libres de zánganos para la fecundación natural de abejas reinas, Vallecitos, Luján, Mendoza, Argentina

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    Se desea averiguar que sector del valle de “Vallecitos", se encuentra libre de zánganos y el comportamiento de la temperatura en tres puntos equidistantes 5 Km. durante la época de fecundación. Durante el verano y dos años consecutivos se instalaron tres puestos de observación. El primero se ubicó en el paraje Los Zorzales 33º 0017!32" S 69º17!3556" O a 1952 mts de altura. El punto distal oeste se encuentra 32º591442" S y 69º 210627" O a 2652 mts sobre el nivel del mar. Las estaciones se equiparon con registrador de temperatura y 5 núcleos de fecundación. El primero de octubre se inicia el experimento; se injertaron celdas reales. A los tres días se revisaron para comprobar nacimiento, en caso negativo se reinjertaron. Doce días más tarde se comprobó fecundación con observación de postura y de la espermateca. Se reinjertan la totalidad de los núcleos. Esto se repite hasta el 15 de febrero. Resultados primer año: negativos. Resultados del segundo año: en la observación del 15 de Enero la estación Los Zorzales positivo para una de las 5 reinas. Esta situación no volvió a presentarse. Conclusión: cualquiera de los tres puntos puede usarse para la fecundación.It is desired to find out which sector of “Vallecitos" valley is free of drones and the behavior of the temperature in three points equidistant 5 km during fecundation time. It was installed three observation posts during summer, for two consecutive years. The first one was located in Los Zorzales 33º 0017! 32 "S 69º17! 3556" O at 1952 m of height. The west distal point is located on 32º591442 "S and 69º 210627" O at 2652 m above sea level. The stations were equipped with temperature recorder and 5 fecundation nuclei. The experiment begins on October 1st; It was grafted real cells. Three days later they were reviewed in order to check the birth; in negative case, they were re-grafted. Twelve days later fecundation was verified with observation of laying and spermatheca. All nuclei were re-grafted. This is repeated until February 15th. First year results: negatives. Second year results: in the observation of January 15th, positive for one of the 5 queens in Los Zorzales station. This situation did not happen again. Conclusion: any of the three points can be used for fecundation.Fil: Juricich, Juan Marcos. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Lema, Diego

    The enamel microstructure of Manidens condorensis: New hypotheses on the ancestral state and evolution of enamel in Ornithischia

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    Previous studies on enamel microstructure in Ornithischia have focused on derived lineages of this clade based on species from the northern hemisphere. Here we describe the enamel microstructure of Manidens condorensis from the late Early Jurassic of Argentina that belongs to Heterodontosauridae (interpreted as the basal-most clade of Ornithischia). Enamel microstructure in the cheek teeth lacks a basal unit layer, presents incipient divergent crystallite as the dominant enamel type and parallel crystallite enamel type (with or without incrementing lines). Enamel of maxillary and dentary teeth differs from each other in enamel distribution (asymmetric vs. symmetric), structure (presence vs. absence of tubules, and less vs. more abundant parallel crystallite enamel with incrementing lines) and ordering (regular ordering of enamel types vs. in patches). The enamel microstructure of Manidens is the simplest of all known Ornithischia, and is more similar to that of the sauropodomorph Plateosaurus than to the one reported for the basal theropod Coelophysis. Similarities within Ornithischia are present with pachycephalosaurids and, to a lesser extent, with ankylosaurs. Phylogenetic optimization of enamel characters in Ornithischia allows the inference of new ancestral states for the internal nodes of the major lineages and to highlight evolutionary transformations: (i) absence of a basal unit layer and presence of parallel crystallite and incipient divergent columnar enamel as the ancestral state for Ornithischia; (ii) the shared presence of incipient divergent columnar units or poorly developed divergent columnar enamel in Pachycephalosauridae and Thyreophora represents a retention of the plesiomorphic ornithischian condition; (iii) the wavy enamel of Dryomorpha evolved from the ancestral incipient divergent columnar units present in Ornithopoda and; (iv) enamel thickness and asymmetry has independently evolved at least four times in Ornithischia.Fil: Becerra, Marcos Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; ArgentinaFil: Pol, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; Argentin
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