1,308 research outputs found

    Commissions Carte de l'Espagne dans les années 1850

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    La necesidad de contar con un mapa de base científica que cubriera todo el territorio español llevó al Estado a crear en paralelo varias Comisiones con cometidos geodésicos, topográficos y cartográficos durante la década de 1850. La labor simultánea de estas Comisiones se prolongó hasta 1859, cuando se aprobó la Ley de Medición del Territorio, que las fusionó en un único organismo. Este artículo analiza aspectos técnicos de los trabajos que realizaron estas Comisiones a partir de la información contenida en algunos documentos que custodia el Archivo Topográfico del IGN. Las conclusiones que se extraen son que estas Comisiones acometieron operaciones geodésicas que resultaron cruciales en el establecimiento ulterior de la red de triangulación peninsular, realizaron mediciones topográficas que fueron reutilizadas veinte años después en el levantamiento del Mapa Topográfico Nacional, e idearon las características catastrales que fueron adoptadas durante todo el siglo posterior para el Catastro de España.The need to have a scientific map covering the whole Spanish territory led the Government in the 1850´s to the foundation of various Commissions with powers on geodesy, topography and cartography. These several Agencies worked simultaneously until 1859, when the Law on Territory Measuring was passed by Parliament and these Commissions were merged in one single Office. Technical issues of the works accomplished by these Agencies are examined in this article using information included in some of the documents held at the Topographical Archive of the National Geographical Institute of Spain. The main conclusions drawn show that the geodetic works fulfilled by these Commissions were crucial in calculating the geodetic network afterwards, their topographic measurements were reused some twenty years later for accomplishing the National Topographical Map of Spain, and their cadastral guidelines were applied during the following century to the Spanish Cadastre.La grande croissance de la production immobilière dès moitié des années 90 jusqu´en 2007 et puis la forte crise (qui ont été déjà largement décrites) ne peuvent pas, cependant, être compris sans avoir en compte des procès sociodémographiques et du territoire qui ont soutenu l´spirale de la construction immobilière. Cet article a l´objet d´analyser la relation entre la mobilité résidentielle et la création de nouveau logement dans zones métropolitaines en partant de l´hypothèse que c´est précisément celle-là le principal facteur qui stimule la construction dans ces espaces. Pour cet objectif, il a été analysé la relation statistique entre la production immobilière et les flux de mobilité résidentielle entre municipalités dans les zones métropolitaines de Madrid et Seville. Les résultats montrent un scénario dans lequel chaque municipalité a lutté pour attirer les flux de mobilité résidentielle par l´offre de nouveau logement, ce qui a produit un surdimensionnement du stock résidentiel dans ces zones urbaines

    Eficàcia dels porters en els Jocs ODESUR i Campionat Panamericà d’Handbol al 2014

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    Objectius. Descriure les característiques de l’eficàcia presentada pels porters al 2014 en els Jocs Sud-americans ­(ODESUR) i en el Campionat Panamericà, en la categoria adults masculina; relacionar aquesta eficàcia amb el resultat dels partits i la classificació final dels seus equips; i analitzar la influència de l’eficàcia dels porters en la probabilitat de guanyar un partit en aquests campionats. Metodologia. Metodologia observacional. Mostra. 3008 llançaments en 32 partits. Principals resultats. Coeficient d’eficàcia del porter (CEP 0.33 i 0.31) i coeficient d’eficàcia ampliat (CEAP 0.40 i 0.38) en tots dos campionats. Diferències significatives entre guanyadors i perdedors en defensa posicional (p<0.01). Conclusions. Els millors resultats van aparèixer davant llançaments de contraatac, mentre que els valors enfront de 7 m van ser baixos. L’eficàcia dels porters es va relacionar amb el resultat dels partits i la classificació final dels seus equips. Els equips guanyadors van presentar millors valors durant les fases de defensa posicional. La probabilitat de guanyar un partit es veu influenciada per l’eficàcia dels porters, però també pel nombre de llançaments rebuts

    A Spherical Brain Mapping of MR Images for the Detection of Alzheimer's Disease

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    Magnetic Resonance Imaging (MRI) is of fundamental importance in neuroscience, providing good contrast and resolution, as well as not being considered invasive. Despite the development of newer techniques involving radiopharmaceuticals, it is still a recommended tool in Alzheimer’s Disease (AD) neurological practice to assess neurodegeneration, and recent research suggests that it could reveal changes in the brain even before the symptomatology appears. In this paper we propose a method that performs a Spherical Brain Mapping, using different measures to project the three-dimensional MR brain images onto two-dimensional maps revealing statistical characteristics of the tissue. The resulting maps could be assessed visually, but also perform a significant feature reduction that will allow further supervised or unsupervised processing, reducing the computational load while maintaining a large amount of the original information. We have tested our methodology against a MRI database comprising 180 AD affected patients and 180 normal controls, where some of the mappings have revealed as an optimum strategy for the automatic processing and characterization of AD patterns, achieving up to a 90.9% of accuracy, as well as significantly reducing the computational load. Additionally, our maps allow the visual analysis and interpretation of the images, which can be of great help in the diagnosis of this and other types of dementia.This work was partly supported by the MICINN under the TEC2008-02113 and TEC2012-34306 projects and the Consejerıa de Econom´ıa, Innovacion, Ciencia y Empleo (Junta de Andalucıa, Spain) under the Excellence Projects P09-TIC-4530 and P11-TIC-7103, as well as the “Programa de fortalecimiento de las capacidades de I+D+I en las Universidades 2014-2015”, cofunded by the European Regional Development Fund (ERDF) under Project FC14-SAF-3

    Deep Residual Transfer Learning for Automatic Diabetic Retinopathy Grading.

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    Evaluation and diagnosis of retina pathology is usually made via the analysis of different image modalities that allow to explore its structure. The most popular retina image method is retinography, a technique that displays the fundus of the eye, including the retina and other structures. Retinography is the most common imaging method to diagnose retina diseases such as Diabetic Retinopathy (DB) or Macular Edema (ME). However, retinography evaluation to score the image according to the disease grade presents difficulties due to differences in contrast, brightness and the presence of artifacts. Therefore, it is mainly done via manual analysis; a time consuming task that requires a trained clinician to examine and evaluate the images. In this paper, we present a computer aided diagnosis tool that takes advantage of the performance provided by deep learning architectures for image analysis. Our proposal is based on a deep residual convolutional neural network for extracting discriminatory features with no prior complex image transformations to enhance the image quality or to highlight specific structures. Moreover, we used the transfer learning paradigm to reuse layers from deep neural networks previously trained on the ImageNet dataset, under the hypothesis that first layers capture abstract features than can be reused for different problems. Experiments using different convolutional architectures have been carried out and their performance has been evaluated on the MESSIDOR database using cross-validation. Best results were found using a ResNet50-based architecture, showing an AUC of 0.93 for grades 0 + 1, AUC of 0.81 for grade 2 and AUC of 0.92 for grade 3 labelling, as well as AUCs higher than 0.97 when considering a binary classification problem (grades 0 vs 3).This work was partly supported by the MINECO/FEDER under TEC2015-64718-R, RTI2018-098913-B-I00, PSI2015-65848-R and PGC2018-098813-B-C32 projects. We gratefully acknowledge the support of NVIDIA Cor poration with the donation of one of the GPUs used for this research. Work by F.J.M.M. was supported by the MICINN “Juan de la Cierva - Formacion” Fellowship

    Tratamiento quirúrgico de fracturas toracolumbares por vía posterior con instrumentación y fusión bisegmentaria

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    Analizamos de forma retrospectiva, los resultados clínico-radiológicos y funcionales de pacientes con fracturas vertebrales con y sin afección neurológica, intervenidos quirúrgicamente mediante instrumentación vertebral pedicular de los dos segmentos adyacentes a la vértebra fracturada. Se estudian 30 pacientes que presentan fractura vertebral inestable del segmento toracolumbar, intervenidos desde enero de 1993 hasta diciembre de 2000. En todos los casos se realizó abordaje posterior, con inclusión en 8 casos de la vértebra fracturada y artrodesis posterolateral en todos los casos con injerto antólogo córtico-esponjoso. En dos casos con déficit neurológico se asoció laminectomía con descompresión posterolateral. El resultado clínico-funcional lo valoramos según la escala de Smiley-Webster con resultados excelentes en 22 pacientes. El índice sagital preoperatorio fue de 14,4 grados y postoperatorio de 4,2 grados. La altura media del cuerpo vertebral preoperatorio fue de 46% y postoperatoria de 78%. Los resultados obtenidos con esta fijación son similares a los obtenidos con otras técnicas, que requieren instrumentaciones y fusiones más largas o segundas intervenciones para retirar la fijación.We evaluate retrospectively the clinical, radiologic and functional outcomes of patients admitted to our hospital with unstable vertebral fractures with or without neurologic lesion treated with posterior fusion and transpedicular instrumentation of the upper and lower segment to the fractured vertebra. Thirty patients with unstable vertebral fracture of the thoracolumbar segment surgically managed between January 1993 and December 2000 are studied. The surgical approach was posterior in all cases, with posterolateral fusion with autologous corticocancellous graft. In 8 patients the fractured vertebra was also included. In two cases with neurologic impairment, a posterolateral decompression and laminectomy were associated. The Smiley-Webster score was used for the clinical and functional outcome with excellent results in 22 patients. The preoperative sagittal index was 14,4 degrees and improved to 4,2 degrees after surgery. The mean of vertebral body height was 46% preoperatively, and 78% postoperatively. The results obtained with this fixation are similar to other devices which require longer fusion and instrumentation or a second procedure to remove the hardware

    Empirical Functional PCA for 3D Image Feature Extraction Through Fractal Sampling.

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    Medical image classification is currently a challenging task that can be used to aid the diagnosis of different brain diseases. Thus, exploratory and discriminative analysis techniques aiming to obtain representative features from the images play a decisive role in the design of effective Computer Aided Diagnosis (CAD) systems, which is especially important in the early diagnosis of dementia. In this work, we present a technique that allows using specific time series analysis techniques with 3D images. This is achieved by sampling the image using a fractal-based method which preserves the spatial relationship among voxels. In addition, a method called Empirical functional PCA (EfPCA) is presented, which combines Empirical Mode Decomposition (EMD) with functional PCA to express an image in the space spanned by a basis of empirical functions, instead of using components computed by a predefined basis as in Fourier or Wavelet analysis. The devised technique has been used to classify images from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and the Parkinson Progression Markers Initiative (PPMI), achieving accuracies up to 93% and 92% differential diagnosis tasks (AD versus controls and PD versus Controls, respectively). The results obtained validate the method, proving that the information retrieved by our methodology is significantly linked to the diseases.This work was partly supported by the MINECO/ FEDER under TEC2015-64718-R and PSI2015- 65848-R projects and the Consejer´ıa de Innovaci´on, Ciencia y Empresa (Junta de Andaluc´ıa, Spain) under the Excellence Project P11-TIC-7103 as well as the Salvador deMadariaga Mobility Grants 2017. Data collection and sharing for this project was funded by the ADNI (National Institutes of Health Grant U01 AG024904) and DOD ADNI (Depart ment of Defense award number W81XWH-12-2- 0012). ADNI is funded by the National Institute on Aging, the National Institute of Biomedical Imaging and Bioengineering, and through generous contribu tions from the following: AbbVie, Alzheimer’s Asso ciation; Alzheimer’s Drug Discovery Foundation; Araclon Biotech; BioClinica, Inc.; Biogen; Bristol Myer Squibb Company; CereSpir, Inc.; Eisai Inc.; Elan Pharmaceuticals, Inc.; Eli Lilly and Company; EuroImmun; F. Ho mann-La Roche Ltd and its ali ated company Genentech, Inc.; Fujirebio; GE Health care; IXICO Ltd.; Janssen Alzheimer Immunother apy Research & Development, LLC.; Johnson & Johnson Pharmaceutical Research & Development LLC.; Lumosity; Lundbeck; Merck & Co., Inc.; Meso Scale Diagnostics, LLC.; NeuroRx Research; Neurotrack Technologies; Novartis Pharmaceuticals Corporation; P zer Inc.; Piramal Imaging; Servier; Takeda Pharmaceutical Company; and Transition Therapeutics. The Canadian Institutes of Health Research is providing funds to support ADNI clin ical sites in Canada. Private sector contributions are facilitated by the Foundation for the National Institutes of Health (www.fnih.org). The grantee organization is the Northern California Institute for Research and Education, and the study is coor dinated by the Alzheimer’s Disease Cooperative Study at the University of California, San Diego. ADNI data are disseminated by the Laboratory for Neuro Imaging at the University of Southern Cali fornia. PPMI a public-private partnership is funded by the Michael J. Fox Foundation for Parkinson’s Research and funding partners, including [list the full names of all of the PPMI funding partners found at www.ppmi-info.org/fundingpartners]

    Label Aided Deep Ranking for the Automatic Diagnosis of Parkinsonian Syndromes.

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    Parkinsonism is the second most common neurodegenerative disease in the world. Its diagnosis usually relies on visual analysis of Emission Computed Tomography (SPECT) images acquired using 123I − io f lupane radiotracer. This aims to detect a deficit of dopamine transporters at the striatum. The use of Computer Aided tools for diagnosis based on statistical data processing and machine learning methods have significantly improved the diagnosis accuracy. In this paper we propose a classification method based on Deep Ranking which learns an embedding function that projects the source images into a new space in which samples belonging to the same class are closer to each other, while samples from different classes are moved apart. Moreover, the proposed approach introduces a new cost-sensitive loss function to avoid overfitting due to class imbalance (an usual issue in practical biomedical applications), along with label information to produce sparser embedding spaces. The experiments carried out in this work demonstrate the superiority of the proposed method, improving the diagnosis accuracy achieved by previous methodologies and validate our approach as an efficient way to construct linear classifiers.This work was partly supported by the MINECO/FEDER under TEC2015-64718- R and PSI2015-65848-R projects. We gratefully acknowledge the support of NVIDIA Corporation with the donation of one of the GPUs used for this research. PPMI - a pub435 lic - private partnership - is funded by The Michael J. Fox Foundation for Parkinson’s Research and funding partners, including Abbott, Biogen Idec, F. Hoffman-La Roche Ltd., GE Healthcare, Genentech and Pfizer Inc

    The impact of associated tenotomies on the outcome of incomplete phalangeal osteotomies for lesser toe deformities

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    Partial or incomplete osteotomy (IO) of the phalanx is recently described in the literature. However, the clinical outcome and the rate of complications when applied to lesser toe deformities (LTD) have been never addressed. This study aims to find out if the association of tenotomies to incomplete or partial phalanx osteotomies has a significant impact on the clinical outcomes, the occurrence of complications, and the recovery time after surgery. Methods: A retrospective review of two cohorts of cases operated in our institution for hallux abductus valgus (HAV) and associated LTD from 2008 to 2014 was carried out. The surgical correction of both HAV and the associated LTD was always performed by minimally invasive techniques. The study included a total of 223 patients (723 IO in 556 toes). In 129 cases, the IO for LTD correction was performed without tenotomies, and in 94, the procedure was combined with flexor and/or extensor tenotomies. Patients were assessed with the American Orthopaedic Foot and Ankle Society (AOFAS) questionnaire before surgery and at 6- and 12-month follow-up. Results: The mean preoperative AOFAS score before surgery was similar in both cohorts. At 12-month follow-up, the cohort without tenotomies showed better recovery (95.7 ± 2.8 versus 92.5 ± 6.8; p < 0.01). AOFAS scores decreased as the number of associated LTD increased (r = − 0.814; p < 0.001). Cases operated on by PO + tenotomy showed a high rate of complications such as delayed union of the osteotomy (p < 0.01), hypertrophic callus (p < 0.01), phalangeal fracture at the osteotomy site (p < 0.01), and lack of correction (p < 0.05). The overall occurrence of adverse events was 38.6% in cases operated by PO + tenotomy and 13.9% in cases receiving PO alone (p < 0.0001). Cases operated on without tenotomy showed a shorter time to complete recovery for daily life activities (37.4 ± 2.3 versus 43.0 ± 1.7 days; p < 0.01). Conclusion: The performance of associated tenotomies to incomplete phalanx osteotomies provides worse clinical outcomes, higher complication rates, and longer recovery time as compared to similar forefoot surgeries without tenotomies.Podologí

    Eficacia del ataque y del lanzamiento de los cuatro primeros clasificados en balonmano masculino de los Juegos ODESUR 2014 = Effectiveness of the attack and the throw of the first four teams in the Men's Handball Games ODESUR 2014

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    10 p.El objetivo de este estudio fue analizar la eficacia de las acciones de ataque de los cuatro primeros clasificados en balonmano masculino de los Juegos Suramericanos 2014 (ODESUR) y comparar con los principales torneos internacionales (JJOO, CM y CE). No se han encontrado antecedentes de estudios en esta competición del circuito olímpico. Se siguieron las pautas establecidas para la metodología observacional. Los resultados mostraron que dentro de los juegos Suramericanos se observaron diferencias entre ganadores y perdedores en el número de finalizaciones con lanzamiento y en la realización de malos pases. No aparecen diferencias significativas en la eficacia de lanzamiento. Estos niveles de eficacia del ataque y lanzamiento fueron inferiores a otras competiciones de alto nivelS
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