1,717 research outputs found
Artropatía neuropática diabética múltiple: aportación de un caso
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
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
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
[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
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