1,717 research outputs found

    Artropatía neuropática diabética múltiple: aportación de un caso

    Get PDF
    Se presenta un caso de artropatía neuropática múltipl e en un varón de 35 años de edad afecto de una diabetes mellitus tipo I grave y mal controlada, de larga evolución. La artropatía debutó a los 30 años con una fractura espontáne a del cuello de l astrágal o y fractur a de l maleól o media l tra s un traumatism o bana l de tobillo . Posteriormente , cuatro años y medio más tarde, presenta una fractura espontánea del calcáneo contralateral y tres mese s despué s una fractura del platillo tibial interno de la rodilla izquierda. Los autores analizan los factores de riesgo para desarrollar una artropatía neuropática severa, así como el tratamiento más apropiado.We present a cas e of multipl e neuropathi c arthropaty in a 35 year-old male with a grave and poorly controlled mellitus diabetes Type I, of long duration. The arthropaty began at age 30 with a spontaneous fracture of the neck of the talus and fracture of the medial maleolo following a slight trauma of the ankle. Four and a half year s later he presented a spontaneous fracture of the contralateral calcaneous, and three months later a fracture of the internal tibial plateau of the left knee. The authors analyze the risk factors for developing a severe neuropathi c arthropaty, as well as the most appropriate treatment

    Análisis histológico del crecimiento tisular en la fibra de carbono y en la prótesis de polietilenotereftalato cuando se utilizan como sustitutos del ligamento cruzado anterior

    Get PDF
    Se realiza un análisis histológico del crecimiento tisular en la fibra de carbono y en la prótesis de polietilenotereftalato cuando se utilizan para reemplazar al ligamento cruzado anterior (LCA). La fibra de carbono induce la formación de un tejido conectivo organizado que se extiende siguiendo la dirección de las fibras, dando lugar a un tejido similar histológicamente al ligamento en las zonas donde se ha conservado la disposición longitudinal de los filamentos de carbono. En las zonas en las que los filamentos se han roto, la inducción fibroblástica es importante pero desordenada, dando lugar a un tejido conectivo irregular. La prótesis de polietilenotereftalato actúa como inductor de una fuerte reacción inflamatoria de tipo granulomatoso, dando lugar posteriormente a cicatrices fibrosas, con un tejido conectivo irregular. Tan solo a nivel de la vaina periprotésica se aprecia una disposición en paralelo que recuerda al ligamento. Los autores dudan del efecto funcional del crecimiento tisular en los ligamentos sintéticos cuando se utilizan como sustitutos del LCAWe have carried out and histologic analysis of tissue ingrowth in carbon fiber and polyethylene terephthalate ligament prostheses when used to reconstruct the anterior cruciate ligament (ACL). Carbon fiber induces the formation of a connective tissue so that it extends in the direction of the fibers, producing a tissue histologically similar to the ligament in the zones where the longitudinal disposition of the carbon filaments are conserved. In the zones where the filaments are broken, fibroblastic induction is important but disordered, producing an irregular connective tissue. Polyethylene terephthalat e ligament prostheses acts as an inductor of strong inflammatory reaction (granulomatous type), in turn producing fibrous scars, with an irregular connective tissue. Only at the periprosthetic level, a parallel disposition is observed, resembling the ligament. We doubt about the functional effect of the tissue ingrowth in synthetic ligaments when used as substitutes for ACL

    Semiclassical zero-temperature corrections to Schwarzschild spacetime and holography

    Get PDF
    Motivated by the quest for black holes in AdS braneworlds, and in particular by the holographic conjecture relating 5D classical bulk solutions with 4D quantum corrected ones, we numerically solve the semiclassical Einstein equations (backreaction equations) with matter fields in the (zero temperature) Boulware vacuum state. In the absence of an exact analytical expression for in four dimensions we work within the s-wave approximation. Our results show that the quantum corrected solution is very similar to Schwarzschild till very close to the horizon, but then a bouncing surface for the radial function appears which prevents the formation of an event horizon. We also analyze the behavior of the geometry beyond the bounce, where a curvature singularity arises. In the dual theory, this indicates that the corresponding 5D static classical braneworld solution is not a black hole but rather a naked singularity.Comment: 26 pages, 4 figures; revised version (title changed, conclusions shortened), published as Phys. Rev. D73, 104023 (2006

    A review of modelling and optimisation methods applied to railways energy consumption

    Full text link
    [EN] Railways are a rather efficient transport mean, and yet there is increasing interest in reducing their energy consumption and making them more sustainable in the current context of climate change. Many studies try to model, analyse and optimise the energy consumed by railways, and there is a wide diversity of methods, techniques and approaches regarding how to formulate and solve this problem. This paper aims to provide insight into this topic by reviewing up to 52 papers related to railways energy consumption. Two main areas are analysed: modelling techniques used to simulate train(s) movement and energy consumption, and optimisation methods used to achieve more efficient train circulations in railway networks. The most used methods in each case are briefly described and the main trends found are analysed. Furthermore, a statistical study has been carried out to recognise relationships between methods and optimisation variables. It was found that deterministic models based on the Davis equation are by far (85% of the papers reviewed) the most common in terms of modelling. As for optimisation, meta-heuristic methods are the preferred choice (57.8%), particularly Genetic Algorithms.Martínez Fernández, P.; Villalba Sanchis, I.; Yepes, V.; Insa Franco, R. (2019). A review of modelling and optimisation methods applied to railways energy consumption. Journal of Cleaner Production. 222:153-162. https://doi.org/10.1016/j.jclepro.2019.03.037S15316222
    corecore