Diseño de un dispositivo para rehabilitación de rodilla mediante la optimización de mecanismos

Tesis de Maestría. Diseño de un dispositivo para rehabilitación de rodilla mediante la optimización de mecanismos.La articulación de rodilla es esencial para el sistema musculoesquelético del cuerpo humano, ya que cumple con dos funciones: permite soportar el peso del cuerpo y moverse a través del espacio. Al ser una articulación que está sometida a constante carga, está propensa a sufrir lesiones, enfermedades o patologías (artritis, lesiones y trastornos de cartílagos, lesiones en los ligamentos, entre otras), algunas de las cuales, para ser tratadas requieren de intervención quirúrgica y de un proceso de rehabilitación; el cual permite recuperar el movimiento de la articulación mediante ejercicios de extensión y flexión, ya sea de manera pasiva o activa. Los ejercicios de extensión y flexión pasiva generalmente son conducidos por parte de un médico o especialista (fisioterapeuta), sin embargo, ante el creciente número de pacientes con problemas de rodilla, se han desarrollado dispositivos de rehabilitación pasivos enfocados a la recuperación del movimiento en la articulación por medio de la extensión y flexión de rodilla, el rango de flexión que alcanzan es de 120°, y si se requiere desarrollar un rango mayor de flexión, estos dispositivos no son capaces de cubrirlo, por esta razón se realizó el diseño de un dispositivo de rehabilitación el cual abarca un rango de movimiento completo. Para su desarrollo se empleó la metodología clásica de diseño, se definieron 4 diseños conceptuales, se realizó la síntesis dimensional de los mecanismos en cada uno de ellos, se analizaron los resultados y se realizó la síntesis óptima al diseño conceptual seleccionado, pasando previamente por una etapa de rediseño, con el cual se logró obtener un mecanismo de 6 barras de un grado de libertad. Con el mecanismo optimizado se procedió al desarrollo del diseño de detalle. Los resultados mediante la simulación del ensamble y movimiento del diseño permitieron verificar el correcto funcionamiento y no se encontraron interferencias entre los eslabones del mecanismo, o entre los componentes del dispositivo y el análisis de elementos finitos permitió verificar la resistencia de los materiales propuestos

La condición shemática del hombre

10 p.En tiempos actuales se habla de la crisis a la cual se está enfrentando la persona humana; sin embargo, debemos preguntarnos si realmente existe tal crisis en la actualidad: ¿nos enfrentamos a un ambiente particular de crisis distinto de la crisis propia de la existencia humana, una crisis que nos obligue a reunirnos y repensar nuestra condición? Es decir, si, como parece, siempre ha habido pobreza, guerras, corrupción, desnudez, abandono, violencia, etc., por qué ahora esta torcedura del tronco de la humanidad es presentada con tonos dramáticos y patéticos, como si nos enfrentáramos a algo distinto de la torcida naturaleza humana. Aclaremos pues si esta supuesta crisis que vivimos es algo más que un supuesto.La crisis presente El olvido de la escucha La dimensión shemática Conclusión Referencia

Preparation and characterization of tin (II) oxide powder as p-type semiconductor for its deposition by ink jet printing

Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Any: 2014, Tutora: Anna Vilà ArbonesThe synthesis through a simple chemical route of SnO powder was successfully done. By using a home-made Hall-effect setup, its p-type behaviour is confirmed, showing high hole mobility around 102 cm2·V-1·s-1 and low resistivity ρ=6.52 Ω·m. Moreover the powder exhibits an interesting behaviour with the temperature changing its conformation to SnO2 that is n-type semiconductor

A new catalogue of XCS sources in the DES-Y3 region and its application to test gravity models using galaxy cluster profiles

Galaxy clusters are the largest gravitationally collapsed structures in the Universe. X-ray observations of clusters provide information on dark matter and the structure formation in the Universe over cosmological time. This can be used to constrain cosmological parameters that are complementary to other cosmological probes. Taking advantage of the potential galaxy clusters have, in combination with the most recent astronomical surveys for cluster finding, allows us to produce leading constraints on cosmological models. The XCSDR2-DESY3 cluster catalogue, a subset of the XMM Cluster Survey (XCS) Data Release 2 within the Dark Energy Survey (DES) Year 3 footprint, constitutes approximately 722 optically-confirmed clusters. Most of these clusters have associated spectroscopic or photometric redshifts, reliable X-ray bolometric luminosities, and X-ray temperatures. The catalogue is split into samples for different research areas; e.g. high redshift clusters for galaxy evolution; clusters with spectroscopic redshifts for scaling relations and cosmology; and high temperature clusters for combined multi-wavelength studies. The aim of building this sample is to lay the groundwork for the next generation of wide-area and deep joint optical and X-ray galaxy cluster datasets. Since gravity has a central role in galaxy cluster formation, clusters act as astrophysical laboratories to test modified theories of gravity models in the outskirts of galaxy clusters. By comparing X-ray and weak lensing profiles, it is possible to put constrains on such models, particularly those which rely on screening mechanisms or those that postulate an emergent gravity in the outskirts of clusters to substitute dark matter. By combining detected X-ray clusters with weak lensing data from DES,we were able to place constraints on these type of models. The results are found to be consistent with general relativity,i.e. they do not require gravity to be modified, and are in the same level of confidence as previous studies

Los sintagmas nominales en textos científicos escritos en español

Este trabajo es parte del proyecto DID SOC-01/01-2, "El discurso científico escrito en ciencias naturales y sociales: un estudio comparativo de los textos de especialistas y estudiantes universitarios". Algunos de sus contenidos fueron presentados de manera sintética por Carlos Zenteno en el XV Congreso de la Sociedad Chilena de Lingüística (Santiago, Universidad Metropolitana de Ciencias de la Educación, 13-17 de octubre de 2003).This study examines a number of textual-discoursal functions performed by noun phrases in scientific articles and students' papers written in Spanish, mainly by those which exhibit great syntactic complexity. After identifying and describing 13 micro-functions in operation in both articles published in some Chilean social and natural science journals and in papers written by university students, we propose that syntactically complex noun phrases perform 4 important discoursal-textual macro-functions: referential, predicative, textual configuration, and the hierarchical organisation of information. While the first two functions have received attention in standard Spanish semantically-oriented text grammars, the last two seem to emerge mainly as part of a text-discourse oriented cognitive approach

Individual differences and health in chronic pain: are sex-differences relevant?

Background: Because psychological variables are known to intercorrelate, the goal of this investigation was to compare the unique association between several well-established psychological constructs in pain research and pain-related outcomes. Sex differences are considered because pain is experienced differently across sex groups. Methods: Participants were 456 consecutive chronic pain patients attending a tertiary pain clinic (mean age = 58.4 years, SD = 14.8, 63.6% women). The study design was cross-sectional. Psychological constructs included personality (NEO-Five Factor Inventory), irrational thinking (General Attitudes and Beliefs Scale), and coping (Social Problem Solving Inventory). Outcomes were pain severity and interference (Brief Pain Inventory) and physical, general, and mental health status (Short Form-36). To decide whether the bivariate analyses and the two-block, multivariate linear regressions for each study outcome (block 1 = age, sex, and pain severity; block 2 = psychological variables) should be conducted with the whole sample or split by sex, we first explored whether sex moderated the relationship between psychological variables and outcomes. An alpha level of 0.001 was set to reduce the risk of type I errors due to multiple comparisons. Results: The moderation analyses indicated no sex differences in the association between psychological variables and study outcomes (all interaction terms p > .05). Thus, further analyses were calculated with the whole sample. Specifically, the bivariate analyses revealed that psychological constructs were intercorrelated in the expected direction and mostly correlated with mental health and overall perceived health status. In the regressions, when controlling for age, sex, and pain severity, psychological factors as a block significantly increased the explained variance of physical functioning (ΔR2 = .037, p < .001), general health (ΔR2 = .138, p < .001), and mental health (ΔR2 = .362, p < .001). However, unique associations were only obtained for mental health and neuroticism (β = − 0.30, p < .001) and a negative problem orientation (β = − 0.26, p < .001). Conclusions: There is redundancy in the relationship between psychological variables and pain-related outcomes and the strength of this association is highest for mental health status. The association between psychological characteristics and health outcomes was comparable for men and women, which suggests that the same therapeutic targets could be selected in psychological interventions of pain patients irrespective of sex