320 research outputs found

    Sentinel 2 as a visualization tool of the historical urban growth of cities

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    La observación multiespectral de las ciudades desde el espacio es una herramienta sumamente valiosa para conocer la situación actual de las mismas. Sin embargo, estas mismas imágenes pueden aportar información también sobre la historia pasada de las mismas. En este trabajo se propone el procesado de imágenes Sentinel 2 para visualizar el crecimiento urbano de las ciudades a lo largo del tiempo. En concreto, se ha usado la combinación de bandas 12,11,4 y 12,8,3 para obtener imágenes en falso color que resaltan intensamente los diferentes materiales de techado utilizados en el tiempo. Esta combinación de bandas infrarrojas y roja resultan muy útiles para diferenciar materiales como la teja, el cemento o los materiales sintéticos impermeabilizantes, permitiendo diferenciar a simple vista los distintos barrios que forman la ciudad en función de su época de construcción, dando una visión global de las fases de crecimiento de la ciudad. Este tipo de imágenes resultan muy intuitivas para los estudiantes, convirtiéndose en una valiosa herramienta didáctica y de divulgaciónMultispectral observation of cities from space is a key tool for understanding their current state. Moreover, this kind of imagery may provide insight into the past history of cities. This work proposes the process of Sentinel 2 images for visualizing urban growth of cities in time. In particular, RGB composite of bands 12,11,4 and 12,8,3 provide false color images that highlight the different roofing materials used through history. This particular combination of infrared and red bands are very useful for differentiating materials such as red tile, cement or sinthetic impermeabilization materials, allowing to visually different phases of city growth. These images are very intuitive for students and non professionals, becoming a valuable tool for history teaching and divulgatio

    La huella ecológica de la energía y sus conexiones con economía y geopolítica

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    El consumo energético de la Humanidad es elevado e intensivo en carbono, habiendo sobrepasado los límites razonables por el impacto ambiental a escala global que se está generando. Así lo muestra su alta participación en la huella ecológica de la Humanidad, y ésta, entendida como superficie virtual apropiada para el uso humano, nos permite reflexionar sobre la relación ecosistemas y geoestrategias enfocadas a la entre ampliación de áreas de influencia para utilizar recursos y eliminar residuos. Debería por tanto avanzarse hacia un cambio de modelo energético, tanto en los diseños tecnológicos, como en la búsqueda de nuevos planteamientos económicos respecto a él. Frente a esa necesidad, los poderes energéticos y económicos proponen soluciones que mantienen el actual esquema, apostando por la extracción de los hidrocarburos no convencionales y la agroenergía, acciones que incrementarán de forma significativa nuestra huella ecológica y la expansión territorial de nuestro impacto. En estas páginas se hace una breve revisión de esas opciones de respuesta convencional, y de las propuestas de avance en otras líneas de ciencia y tecnología para cambiar las formas de consumo energético que nos puedan llevar hacia otro modelo menos agresiv

    Influence of the track quality and of the properties of the wheel rail rolling contact on vehicle dynamics

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    This work describes an analytical approach to determine what degree of accuracy is required in the definition of the rail vehicle models used for dynamic simulations. This way it would be possible to know in advance how the results of simulations may be altered due to the existence of errors in the creation of rolling stock models, whilst also identifying their critical parameters. This would make it possible to maximize the time available to enhance dynamic analysis and focus efforts on factors that are strictly necessary.In particular, the parameters related both to the track quality and to the rolling contact were considered in this study. With this aim, a sensitivity analysis was performed to assess their influence on the vehicle dynamic behaviour. To do this, 72 dynamic simulations were performed modifying, one at a time, the track quality, the wheel-rail friction coefficient and the equivalent conicity of both new and worn wheels. Three values were assigned to each parameter, and two wear states were considered for each type of wheel, one for new wheels and another one for reprofiled wheels.After processing the results of these simulations, it was concluded that all the parameters considered show very high influence, though the friction coefficient shows the highest influence. Therefore, it is recommended to undertake any future simulation job with measured track geometry and track irregularities, measured wheel profiles and normative values of wheel-rail friction coefficient

    Spatio-temporal analysis of the degradation of salts-affected soils in the lacustre system of Texcoco Valley (Mexico)

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    El Valle de Texcoco, uno de los cinco lagos que conformaban el gran lago de Tenochticlan en el periodo colonial de la ciudad de México (año 1520), es hoy en día una de las regiones del planeta con mayor superficie de suelos afectados por salinidad extrema (>10 000 ha). La salinidad de los suelos es un grave problema en regiones áridas o semiáridas, ya que afecta a la productividad agrícola y la calidad de las aguas, con graves consecuencias socioeconómicas, como la desertificación y migración a las ciudades. Además, las sales se disuelven con facilidad en el suelo, por lo que se requieren herramientas de monitorización precisas que permitan evaluar la alta variabilidad espacio-temporal de los suelos afectados por sales. Este trabajo tiene como objetivo evaluar el estado de los suelos afectados por salinidad en el valle de Texcoco, así como los cambios de uso de suelo acontecidos en los últimos 30 años. Para ello se emplearán técnicas de GIS, imágenes de satélite Landsat desde la década de los 80 hasta la actualidad (1985-2015), y radiómetros de campo para identificar las firmas espectrales de los suelos en condiciones de laboratorio. Una vez procesadas las imágenes de satélite Landsat (corrección radiométrica y atmosférica, y aplicación de filtros), se identificaron diferentes cubiertas o usos de suelo: agua, vegetación semi-natural, tierras de cultivo, suelos sin vegetación y suelos salinos. Se calcularon diferentes índices radiométricos para distinguir la vegetación de las tierras de cultivo y de los suelos salinos. El sistema de clasificación no supervisada mostró cambios de uso de la tierra en el 80% de la superficie en 30 años. Disminuye el agua potable y las tierras agrícolas e incrementan en más de un 20% los suelos degradados por sales o de uso urbano. Se trata de una región con riesgo extremo por pérdida y degradación de las tierras de cultivo por efecto de la salinidadThe Valley of Texcoco, one of the five lakes that formed the great lake of Tenochticlan in the colonial period of Mexico City (year 1520), is today one of the regions with the largest surface area of soils affected by extreme salinity (>10 000 ha). The salinity of soil is a serious problem in arid or semi-arid regions. It affects to agricultural productivity and water quality, with serious socioeconomic consequences, such as desertification and migration of the rural populations to the cities. So, salts dissolve easily in the soil, so precise monitoring tools are necessary to evaluate the high spatiotemporal variability by salts-affected soils. The aim is to evaluate the state of salts-affected soils in the Texcoco Valley, as well as the land use changes in the last 30 years. GIS, Landsat satellite images from the 1980s to the present (1985-2015), and field radiometers will be used to identify the spectral signatures of salts-affected soils under laboratory conditions. Once processed the multispectral images (radiometric and atmospheric correction, and filters application), different land uses were identified: water, semi-natural vegetation, agricultural lands, soil without vegetation and saline soils. Different radiometric indices were used to differentiate vegetation from agricultural and saline soils. The unsupervised classification system showed changes at 80% of the surface in land use in 30 years. Clear water and agricultural land decreased and increased at 20% the soils degraded by salts or urban use. It is a region with extreme risk due to the salts-affected soil

    MC64-Cluster: Many-Core CPU Cluster Architecture and Performance Analysis in B-Tree Searches

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    The MC64-Cluster computer platform was designed, based on many-core CPU microprocessors: Tile64. MC64-Cluster architecture was outlined in terms of both hardware and software, including commands available to manage jobs and provided application programming interfaces to communicate and synchronize tiles, making this system easy to use. Massively, concurrent-searches of keys in B-trees, which are used in many applications, including bioinformatics, were used. Remarkable performance improvements were obtained when the cluster resources were combined with those available in host machine (hybrid or heterogeneous environments). These results were even more outstanding when analyzed in terms of performance-per-watt, highlighting their green-computing advantages. Together with the cluster architecture, they represent the main contributions of this work. To our knowledge, this is the first cluster implementation of this kind being developed

    Endoplasmic reticulum aminopeptidase 1 (ERAP1) polymorphism relevant to inflammatory disease shapes the peptidome of the birdshot chorioretinopathy-associated HLA-A∗29:02 Antigen

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    Birdshot chorioretinopathy is a rare ocular inflammation whose genetic association with HLA-A∗29:02 is the highest between a disease and a major histocompatibility complex (MHC) molecule. It belongs to a group of MHCI- Associated inflammatory disorders, also including ankylosing spondylitis, psoriasis, and Behç et's disease, for which endoplasmic reticulum aminopeptidases (ERAP) 1 and/or 2 have been identified as genetic risk factors. Since both enzymes are involved in the processing of MHC-I ligands, it seems reasonable that common peptide- mediated mechanisms may underlie the pathogenesis of these diseases. In this study, comparative immunopeptidomics was used to characterize >5000 A∗29:02 ligands and quantify the effects of ERAP1 polymorphism and expression on the A∗29:02 peptidome in human cells. The peptides predominant in an active ERAP1 context showed a higher frequency of nonamers and bulkier amino acid side chains at multiple positions, compared with the peptides predominant in a less active ERAP1 background. Thus, ERAP1 polymorphism has a large influence, shaping the A∗29:02 peptidome through length-dependent and length-independent effects. These changes resulted in increased affinity and hydrophobicity of A∗29:02 ligands in an active ERAP1 context. The results reveal the nature of the functional interaction between A∗29:02 and ERAP1 and suggest that this enzyme may affect the susceptibility to birdshot chorioretinopathy by altering the A∗29:02 peptidome. The complexity of these alterations is such that not only peptide presentation but also other potentially pathogenic features could be affectedThis work was supported by grants SAF2011/25681 (Plan Nacional de I+D+i) to JALC, Binational Science Foundation Grant 2009393 to AA, and an institutional grant of the Fundacion Ramon Areces to the CBMS

    Comparative study of real-time pcr (Taqman probe and sybr green), serological techniques (elisa, ifa and dat) and clinical signs evaluation, for the diagnosis of canine leishmaniasis in experimentally infected dogs

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    Canine leishmaniasis (CanL) diagnosis is not fully resolved. Currently, two specific methodologies are in continuous development, the detection of the parasite DNA or RNA in target organs and the detection of specific antibodies against Leishmania sp. For a correct diagnosis, it has been shown that the joint use of this type of test is necessary. In this work, a Sybr Green and a TaqMan Probe based on real time PCRs (qPCR) was performed for the detection of Leishmania sp. in order to correlate the results with clinicopathological and serological evaluations (IFA, ELISA and DAT) to propose an optimal biological sample to be used to detect the parasite in both early and late stages of the infection. A total of four samples were processed: conjunctival swabs, popliteal lymph node aspirates, bone marrow aspirates, and peripheral blood from experimentally infected dogs belonging to a larger study. Our results indicated that a single non-invasive sample (conjunctival swab) and the application of both types of qPCR would be reliable for determining Leishmania infection as well as the disease stage in dogs, thus avoiding bone marrow, lymph node aspirate or blood samples collection. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/)

    MC64-ClustalWP2: A Highly-Parallel Hybrid Strategy to Align Multiple Sequences in Many-Core Architectures

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    We have developed the MC64-ClustalWP2 as a new implementation of the Clustal W algorithm, integrating a novel parallelization strategy and significantly increasing the performance when aligning long sequences in architectures with many cores. It must be stressed that in such a process, the detailed analysis of both the software and hardware features and peculiarities is of paramount importance to reveal key points to exploit and optimize the full potential of parallelism in many-core CPU systems. The new parallelization approach has focused into the most time-consuming stages of this algorithm. In particular, the so-called progressive alignment has drastically improved the performance, due to a fine-grained approach where the forward and backward loops were unrolled and parallelized. Another key approach has been the implementation of the new algorithm in a hybrid-computing system, integrating both an Intel Xeon multi-core CPU and a Tilera Tile64 many-core card. A comparison with other Clustal W implementations reveals the high-performance of the new algorithm and strategy in many-core CPU architectures, in a scenario where the sequences to align are relatively long (more than 10 kb) and, hence, a many-core GPU hardware cannot be used. Thus, the MC64-ClustalWP2 runs multiple alignments more than 18x than the original Clustal W algorithm, and more than 7x than the best x86 parallel implementation to date, being publicly available through a web service. Besides, these developments have been deployed in cost-effective personal computers and should be useful for life-science researchers, including the identification of identities and differences for mutation/polymorphism analyses, biodiversity and evolutionary studies and for the development of molecular markers for paternity testing, germplasm management and protection, to assist breeding, illegal traffic control, fraud prevention and for the protection of the intellectual property (identification/traceability), including the protected designation of origin, among other applications

    Continuous Plasma density measurement in TJ-II infrared interferometer-Advanced signal processing based on FPGAs

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    This work presents the behavioral simulation in an FPGA of a novel processing system for measuring line average electronic density in the TJ-II stellarator diagnostic, Infra-Red Two-Color Interferometer. Line average electronic density is proportional to phase difference between probing and reference signals of the interferometer, as the Appleton–Hartree cold plasma model states. The novelty of the approach is the development of a real time measuring system where research work has been carried out in two ways: a new interpolation algorithm and the implementation of a new specific processor on an FPGA. The main goal of this new system is to measure line plasma electronic density for several channels in real time, also it will be useful to eliminate intermediate mixing frequency stages (the output signals coming from the interferometer are going to be directly sampled) and finally to generate real time density signals for control purposes in TJ-II and in other diagnostics. This device is intended to be the new data acquisition-processing system for the future six channel infrared interferometer that requires at least 14 input signals. The knowledge acquired could be useful in the design of W7-X and ITER IR-interferometer data acquisition and processing systems

    Software público, libre, abierto, gratuito, privativo y comercial para la innovación y mejora de la calidad en la docencia, investigación, gestión y asistencia

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    The public free software (now renamed as open software) is the basis of the open source software (OSS) project. This initiative promotes the use of open standards and platform-independent accessibility. Many OSS products are free or low cost, which allows their deployment even in the absence of large economic resources (developing countries, schools, etc.). Besides, their source code can be modified, adapted and optimized by anyone, since it is public. Nevertheless, the OSS may also have drawbacks. Thus, its development may not be as orderly and hierarchical as the privative software is, and may not have an appropriate funding. This may jeopardize the ease of use and coherence of the final product, increasing the transition, training and technical support costs. Besides, it must be taken into account that there is also commercial open software, as well as free privative software. In any case, the excellence of the software may be independent of such variables. Thus, the best strategy is the coexistence and free competition of all kinds of software. This will allow a quality improvement and an innovation enhancement, which will benefit the education, research, management and assistance at the university in particular and at the whole society in general.El software público libre es el fundamento del movimiento de software de fuente abierta (OSS). Éste puede facilitar el uso de estándares abiertos, con accesibilidad independiente de plataforma informática. El bajo coste o gratuidad de muchos productos OSS permite su implantación cuando los recursos económicos son escasos (países en desarrollo, escuelas, etc.). Además, su código se puede modificar, adaptar y mejorar por cualquiera, ya que es público. No obstante, el OSS también puede presentar inconvenientes. Así, su desarrollo puede no ser tan ordenado y jerárquico como el del software privativo y puede no tener una financiación apropiada. De este modo, puede verse comprometida la facilidad de uso y coherencia del producto final. Ello puede incrementar los costes de transición, entrenamiento y soporte técnico. Por otra parte, conviene recordar que existe software libre comercial y software privativo gratuito. En cualquier caso, la excelencia del software puede ser independiente de dichas variables. Por tanto, la mejor estrategia es la coexistencia y libre competencia de todo tipo de software. Así se puede conseguir una mejora de calidad y una potenciación de la innovación, que beneficie a la docencia, investigación, gestión y asistencia universitarias en particular, así como a la sociedad en general
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