Ingeniería inversa del TALGO-I

I Premio para jóvenes Ingenieros Ferroviarios TRIA Railway R&D, 2011.Esta iniciativa nace de la voluntad de Talgo y Renfe por recuperar el proyecto innovador del Talgo I, ideado por el Sr. Alejandro Goicoechea Omar. Actualmente, apenas se conservan documentos sobre el >, nombre por el que era conocido en la época, y cada vez son menos los testimonios a los que consultar. Algunas fotografías y artículos son el único material de archivo existente sobre un proyecto que revolucionó la historia del ferrocarril e hizo evolucionar al tren hasta llegar al que conocemos hoy en día. En base a la poca información existente, y a partir de una ingeniería inversa sobre el Talgo I, se ha diseñado pieza a pieza todo el conjunto de cada uno de los cuatro vagones, a partir de técnicas de dibujo como la perspectiva cónica aplicada a las imágenes existentes y las medidas conocidas de los vagones. Ya modelada cada pieza por separado, se ha hecho un estudio para comprobar si las geometrías aplicadas eran correctas dependiendo de si en la época se hubieran podido fabricar y con qué se habrían construido. Una vez obtenido el diseño final, se ha estudiado su posible proceso de fabricación para un correcto montaje. Cabe que destacar que se han tenido en cuenta las técnicas y recursos de la época en que fue construido el Talgo I. Con todas las estructuras modeladas en tres dimensiones, con CATIA V5R18, se ha puesto a prueba su resistencia mediante el módulo de simulación de elementos finitos (FEM), primero con el peso único del vagón, y seguidamente añadiendo el peso de los viajeros. En las simulaciones se ha podido observar como la estructura con el simple peso del vagón estaba al borde del colapso, ya que las tensiones de Von Mises se acercaban al límite elástico del material utilizado (AISI 1015). Al añadir el peso de los viajeros las tensiones han sobrepasado el límite elástico. Por lo tanto, como solución se ha propuesto una mejora básica para optimizar el diseño creado. Por último se ha acotado cada parte de los cuatro vagones modelados para poder dejar constancia de las dimensiones aproximadas obtenidas.Award-winnin

Evaluation of random forests on large-scale classification problems using a bag-of-visual-words representation

Random Forest is a very efficient classification method that has shown success in tasks like image segmentation or object detection, but has not been applied yet in large-scale image classification scenarios using a Bag-of-Visual-Words representation. In this work we evaluate the performance of Random Forest on the ImageNet dataset, and compare it to standard approaches in the state-of-the-art.Peer ReviewedPostprint (author’s final draft

Sistema automático para determinar estructuras cristalinas por difracción de rayos-X

Se desarrolla en este trabajo un sistema de calculo para la determinación de estructuras cristalinas por difracción de rayos-X. Las caracteristicas de este sistema son: Incorporar los métodos y las técnicas más recientes. Obtener la máxima velocidad de ejecución posible. Obtener la total automatización del proceso. Y conseguir la mínima ocupacion de memoria posible

Progress in powder and surface X-ray diffraction crystallography

Una de les fites científiques més importants del segle XX ha estat sens dubte la descoberta de la difracció dels raigs X per la matèria cristal·lina i l'aprofitament d'aquest procés en la determinació de l'estructura cristal·lina dels materials. Tanmateix, no és fins a la darreria de segle que arriba la maduresa en aquest camp amb la solució gairebé automàtica de les estructures cristal·lines petites. Amb la maduresa emergeixen noves aplicacions dels mètodes de difracció. al destacar, entre les més importants per a la Ciència de Materials, la determinació de les estructures cristal·lines a partir de dades provinents de la difracció dels raigs X en pols cristal·lina, així com també la determinació de la disposició atòmica en les superfícies dels substrats i dels corresponents dipòsits, quan n'hi ha. Com que els avenços en aquestes dues aplicacions van estretament lligats a una reinterpretació recent dels mètodes directes tradicionals de solució d'estructures cristal·lines, s'ha cregut convenient fer-ne una breu introducció. Seguidament, es comentaran les modificacions introduïdes en aquests mètodes, per tal de poder tractar les particularitats específiques d'aquestes dues noves aplicacions, i finalment, es descriuran alguns exemples.One of the most important scientific achievements of the XX century has been without any doubt the discovery of X-ray diffraction by crystalline matter and the subsequent use of this process to determine the crystal structures of the materials. This field matured at the end of the century with the almost automated solution of the crystal structures of small compounds, allowing various new applications of X-ray diffraction methods to emerge. Among the most relevant ones for Materials Sciences one may mention the solution of crystal structures from X-ray powder diffraction intensity data or the determination of atomic arrangements in the surfaces of substrates and, eventually, of the corresponding depositions. Since these advances are closely related to a recent reinterpretation of the traditional direct methods of solving crystal structures, a short introduction to them will be given first. Then we deal with the modification of such methods to cope with the particularities of these two applications and, finally, some examples will be described

New Biomarkers in Acute Tubulointerstitial Nephritis: A Novel Approach to a Classic Condition

Acute tubulointerstitial nephritis (ATIN) is an immunomediated cause of acute kidney injury. The prevalence of ATIN among the causes of acute kidney injury (AKI) is not negligible, especially those cases related to certain drugs. To date, there is a lack of reliable non-invasive diagnostic and follow-up markers. The gold standard for diagnosis is kidney biopsy, which shows a pattern of tubulointerstitial leukocyte infiltrate. The urinalysis findings can aid in the diagnosis but are no longer considered sensitive or specific. Atthe present time, there is a rising attentiveness tofinding trustworthy biomarkers of the disease, with special focus in urinary cytokines and chemokines that may reflect kidney local inflammation. Cell-based tests are of notable interest to identify the exact drug involved in hypersensitivity reactions to drugs, manifesting as ATIN. Certain single-nucleotide polymorphisms in HLA or cytokine genes may confer susceptibility to the disease according to pathophysiological basis. In this review, we aim to critically examine and summarize the available evidence on this topic

Estructura cristal·lina i molecular de perclorbifenil (C12 Cl10)

C12C10 orthorhombic, Pbcn, a=13.375 Å, b=10.498 Å, c=12.001 Å. V=1685.07 Å 3, Z=4, Dx = 1.96 g.cm-3, λ(Cu Kq)=1.54051 Å. Final residual R=0.043 for 841 observed reflexions. Two rings of molecule are perpendicular (87.0º) and related by a binary axis. All atoms of the pentachiorophenyl group lie on a plane. No significant molecular distortion due to the Cl atoms was observed

Clinical features and outcomes in a cohort of patients with immunoglobulin G4-related disease at a university hospital in Spain

Background. Immunoglobulin G4-related disease (IgG4-RD) is a fibro-inflammatory, immune-mediated disorder, which characteristically affects the glandular tissue but has the potential to affect any organ. Methods. We retrospectively reviewed clinical, laboratory, histological characteristics and treatment response during 12 months of follow-up of a cohort of patients with IgG4-RD diagnosed at a tertiary public hospital. Disease activity was assessed by means of the IgG4-RD responder index (IgG4-RD RI). Results. In all, 15 patients have been diagnosed at our Institution and herein studied (80% men), with a median age of 60.7 years and a mean affectation of 2.8 organs per patient. We identified six patients with definitive diagnosis and nine with possible IgG4-RD, according to the Japanese diagnostic algorithm. IgG4-RD RI decreased from a median of 11.3 at baseline to 4.0 after 6 months and 6.2 after 12 months. Relapse occurred in five patients and was associated with lower cumulative steroid doses. Five patients (33.3%) required additional immunosuppressive (IS) drugs. Five adverse events were seen during follow-up: three infections, one deep vein thrombosis and one gastrointestinal bleeding. One patient died of pneumonia. Conclusions. IgG4-RD is an inflammatory disease that can affect any organ. Glucocorticoids were an effective first line of treatment; however, this treatment is associated with important adverse events and relapses occurred in patients with low cumulative doses. As an alternative, IS treatment with rituximab could be an interesting option in those patients

T-lymphocyte in ANCA-associated vasculitis: what do we know? A pathophysiological and therapeutic approach

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is an autoimmune condition that commonly causes kidney impairment and can be fatal. The key participation of B-lymphocytes as ANCA producers and neutrophils as target of these antibodies is widely described as the mechanism of endothelial damage in this disease. There has been a rising interest in the role of T-lymphocytes in AAV in recent years. Evidence is strong from animal models, and T-lymphocytes can be found infiltrating kidney tissue and other tissue sites in AAV patients. Furthermore, the different subsets of T-lymphocytes are also key players in the aberrant immune response observed in AAV. Polarization towards a predominant Th1 and Th17 response in the acute phase of the disease has been described, along with a decline in the number of T-regulatory lymphocytes, which, in turn, show functional impairment. Interactions between different T-cell subsets, and between T-cells and neutrophils and B-cells, also enhance the inflammatory response, constituting a complex network. Novel therapies targeting T-cell immunity are emerging in this scenario and may constitute an interesting alternative to conventional therapy in selected patients. This review aims to summarize the available evidence regarding T-cell imbalances and functional impairment, especially focusing on renal involvement of AAV