An anisotropic microsphere-based approach for fiber orientation adaptation in soft tissue

Evolutionary processes in biological tissue, such as adaptation or remodeling, represent an enterprising area of research. In this paper, we present a multiscale model for the remodeling of fibered structures, such as bundles of collagen fibrils. With this aim, we introduce a von Mises statistical distribution function to account for the directional dispersion of the fibrils, and we remodel the underlying fibrils by changing their orientation. To numerically compute this process, we make use of the microsphere approach, which provides a useful multiscale tool for homogenizing the microstructure behavior, related to the fibrils of the bundle, in the macroscale of the problem. The results show how the fibrils respond to the stimulus by reorientation of their structure. This process leads to a stiffer material eventually reaching a stationary state. These results are in agreement with those reported in the literature, and they characterize the adaptation of biological tissue to external stimuli.Peer ReviewedPostprint (author's final draft

Hierarchical micro-adaptation of biological structures by mechanical stimuli

Remodeling and other evolving processes such as growth or morphogenesis are key factors in the evolution of biological tissue in response to both external and internal epigenetic stimuli. Based on the description of these processes provided by Taber, 1995 and Humphrey et al., 2002 for three important adaptation processes, remodeling, morphogenesis and growth (positive and negative), we shall consider the latter as the increase/decrease of mass via the increase/decrease of the number or size of cells, leading to a change in the volume of the organ. The work of Rodriguez et al. (1994) used the concept of natural configuration previously introduced by Skalak et al. (1982) to formulate volumetric growth. Later, Humphrey et al. (2002) proposed a constrained-mixture theory where changes in the density and mass of different constituents were taken into account. Many other works about biological growth have been presented in recent years, see e.g. Imatani and Maugin, 2002, Garikipati et al., 2004, Gleason and Humphrey, 2004, Menzel, 2004, Amar et al., 2005, Ganghoffer et al., 2005, Ateshian, 2007, Goriely et al., 2007, Kuhl et al., 2007, Ganghoffer, 2010a, Ganghoffer, 2010b and Goktepe et al., 2010. Morphogenesis is associated to changes in the structure shape (Taber, 1995 and Taber, 2009) while remodeling denotes changes in the tissue microstructure via the reorganization of the existing constituents or the synthesis of new ones with negligible volume change. All these processes involve changes in material properties. Although remodeling and growth can, and usually do, occur simultaneously, there are some cases where these processes develop in a decoupled way. For example, Stopak and Harris (1982) reported some experimental results showing remodeling driven by fibroblasts, with no volume growth. We will assume this scenario in this contribution, focusing exclusively on remodeling processes and on the reorientation of fibered biological structures. It is well known that biological tissue remodels itself when driven by a given stimulus, e.g. mechanical loads such as an increase in blood pressure, or changes in the chemical environment that control the signaling processes and the overall evolution of the tissue. Biological remodeling can occur in any kind of biological tissue. In particular, the study of collagen as the most important substance to be remodeled, in all its types (preferentiallyPeer ReviewedPostprint (author's final draft

Anisotropic microsphere-based approach to damage in soft fibered tissue

The final publication is available at Springer via http://dx.doi.org/10.1007/s10237-011-0336-9An anisotropic damage model for soft fibered tissue is presented in this paper, using a multi-scale scheme and focusing on the directionally dependent behavior of these materials. For this purpose, a micro-structural or, more precisely, a microsphere-based approach is used to model the contribution of the fibers. The link between micro-structural contribution and macroscopic response is achieved by means of computational homogenization, involving numerical integration over the surface of the unit sphere. In order to deal with the distribution of the fibrils within the fiber, a von Mises probability function is incorporated, and the mechanical (phenomenological) behavior of the fibrils is defined by an exponential-type model. We will restrict ourselves to affine deformations of the network, neglecting any cross-link between fibrils and sliding between fibers and the surrounding ground matrix. Damage in the fiber bundles is introduced through a thermodynamic formulation, which is directly included in the hyperelastic model. When the fibers are stretched far from their natural state, they become damaged. The damage increases gradually due to the progressive failure of the fibrils that make up such a structure. This model has been implemented in a finite element code, and different boundary value problems are solved and discussed herein in order to test the model features. Finally, a clinical application with the material behavior obtained from actual experimental data is also presented.Peer ReviewedPostprint (author's final draft

EUPVSEC 2018

There are many characterization techniques available to evaluate the health of solar panels, such as I-V characterization, infrared thermography (IR), photoluminescence (PL) and electroluminescence (EL). EL imaging has become in recent years a powerful diagnostic tool to evaluate PV modules. EL images allow to detect several defects and degradation modes in the solar cells. The failures are observed as dark contrasted areas in the images. Broad dark regions can be detected even in a low resolution image, while a high resolution image is needed to detect some more specific problems such as cracks, multi-cracks or other line-shaped defects.PósterJunta de Castilla y León (programa de apoyo a proyectos de investigación - Ref. VA081U16)Ministerio de Economía, Industria y Competitividad (Proyect ENE2014-56069-C4-4-R

PLAN DE ENTRENAMIENTO FÍSICO PARA LOS CORREDORES PRE- JUVENILES DE FONDO DE LA LIGA CANTONAL DE MANTA (Original)

The complexity and multiversity in obtaining sporting results currently requires the need to offer methodological alternatives for the process of sports training that guide coaches and athletes towards a more effective and competitive performance, that is why the physical component of this difficult preparation requires changes and adequate planning. The objective is to: Design a training plan for the development of the physical preparation of the base runners of the Cantonal League of Manta. Theoretical and empirical methods are used that allow to offer results in the determination of the main insufficiencies. The universe of work was constituted by two strata, seven athletes of both sexes and a teacher, which were the object of application of instruments such as interview with the teacher, an initial observation guide to know the current state of the sports training process and the realization of a physical test. The physical training plan is the proposed solution, its character of guidance and orientation to the sports coach offers the different stages of the training process, with objectives for each physical component, depending on the mesocycle and microcycles; its close relationship with the other components that make up the planning macrostructure is recognized, preparatory competences, medical tests, psychological tests, as well as fundamental competence are declared. This proposal has social relevance when responding to the training of the athlete’s long-distance runner in search of a better sporting result for the Canton of Manta.La complejidad y multidiversidad en la obtención de resultados deportivos exige en la actualidad, la necesidad de ofrecer alternativas metodológicas para el proceso de entrenamiento deportivo que orienten a entrenadores y atletas hacia un rendimiento más efectivo y competitivo, es por eso que el componente físico de esta difícil preparación exige de cambios y adecuada planificación. Se plantea como objetivo: Diseñar un plan de entrenamiento para el desarrollo de la preparación física de los corredores de fondo de la Liga Cantonal de Manta. Se emplean métodos teóricos y empíricos que permiten ofrecer resultados en la determinación de las principales insuficiencias. El universo del trabajo estuvo constituido por dos estratos, siete atletas de ambos sexos y un profesor, lo que fueron objeto de aplicación de instrumentos como entrevista al profesor, una guía de observación inicial para conocer el estado actual del proceso de entrenamiento deportivo y la realización de un test físico. El plan de entrenamiento físico constituye la propuesta de solución, su carácter de guía y orientación al entrenador deportivo ofrece las distintas etapas del proceso del entrenamiento, con objetivos para cada componente físico, dependiendo del mesociclo y microciclos; se reconoce su estrechamente relación con los demás componentes que conforman la macroestructura de planificación, se declaran las competencias preparatorias, pruebas médicas, test psicológico, así como la competencia fundamental. Esta propuesta posee pertinencia social al responder a los entrenamientos de los atletas de fondo en busca de un mejor resultado deportivo para el Cantón de Manta

La formación de competencias profesionales en los estudiantes de Comunicación Social de las emisoras universitarias en España y Portugal: situación y resultados asimétricos

El artículo expone los resultados de una investigación sobre las emisoras universitarias de España y Portugal realizada en el 2014. El objetivo de la investigación fue conocer las competencias profesionales que adquieren los alumnos tras su paso por las estaciones de radio. La investigación se apoyó en el enfoque de diferentes estudios sobre competencias y perfiles profesionales radiofónicos demandados por el sector de la comunicación y contemplados también en el Espacio Europeo de Educación Superior (Cordeiro, 2005; Lazo, 2009; Perona y Barbeito, 2010; Peinado, Fernández Sande, Rodríguez Barba, Ortiz Sobrino, 2011; Agustín Lacruz, Marta-Lazo & Ubieto, 2013). La metodología se basó en un cuestionario con tratamiento estadístico descriptivo (Montero Lorenzo, 2007). Los resultados reflejan que en estas emisoras se adquieren competencias multidisciplinares y polivalentes para la radio. También revelan que en España existe una fuerte relación entre universidad y radio universitaria, mientras que en Portugal esa relación es bastante menor y apenas participan estudiantes

De las primeras experiencias radiofónicas universitarias en Latinoamérica y España al trabajo asociativo y colaborativo

Las radios universitarias resultan ser un medio alternativo al sistema radiodifusor en cada uno de los países en los que se desarrollan, planteando otro tipo de contenidos. A lo largo de este artículo pretendemos acercarnos a las primeras experiencias radiofónicas universitarias de Latinoamérica, donde, en países como Argentina o Chile, existen este tipo de emisoras desde mediados de los años 20. No en vano en el 2014, se ha celebrado el 90 aniversario de la primera radio universitaria de Latinoamérica, Radio Universidad Nacional de La Plata. Sin embargo, en España esta tradición es mucho más reciente, nada que ver con lo sucedido en esos países del cono sur del continente americano. La primera experiencia española es la desarrollada en la Universidad Nacional de Educación a Distancia. Radio UNED que ha conmemorado, también, en ese mismo año, su 40 aniversario. Esos fueron los inicios, marcados por experiencias particulares. Sin embargo, la situación actual se caracteriza por la unión de las emisoras en redes o asociaciones de colaboración nacionales e incluso, como en el caso de Iberoamérica, transnacionales. La constitución de estas redes ha propiciado una expansión del fenómeno de la radio universitaria en los últimos años

Modelo matemático del crecimiento microbiológico en carne equina refrigerada: su importancia en la calidad de la carne

Horsemeat is an important economic resource for our country, as Argentina is considered one of the leading world exporters of horsemeat. But there is little research about the quality of it. It was examined the effect of: (i) storage temperature (0, 4˚C) and (ii) gaseous permeability of the packaging film (polyethylene and EVA SARAN EVA for vacuum packaging) on the growth of bacteria (Total Aerobic Mesophilic Heterotrophic Bacteria, Enterobacteriaceae and Pseudomonas sp.) isolated from horse muscle. Microbial growth was modelled using Gompertz or the Linear Regression Models. The lowest final bacteria counts were obtained with the combination of 0˚C and vacuum packaging. At higher temperatures, 4˚C, there were no significant differences (p<0.05) among the final counts in relation to both films. The lowest values of μ (microbial growth rate) for the development of studied microorganisms were observed in samples stored in EVA SARAN EVA.La carne equina es un importante recurso económico para nuestro país, ya que Argentina es considerado uno de los principales exportadores mundiales de estas carnes. Pero existen pocos datos sobre la calidad de la misma. El efecto de: (i) la temperatura de almacenamiento (0, 4ºC) y (ii) la permeabilidad gaseosa de la película de envase (polietileno y EVA EVA SARAN para envasado al vacío) sobre el desarrollo de microorganismos (Aerobios mesófilos heterótrofos totales, Enterobacteriaceae y Pseudomonassp.) aislados de músculo equino, fue examinado. El desarrollo microbiano se modeló usando el modelo de Gompertz o de regresión lineal. Los recuentos finales bacterianos más bajos fueron los obtenidos con la combinación de 0˚C y envasado al vacío. A temperaturas más altas, 4ºC, no se encontraron diferencias significativas (p &lt; 0.05) entre los recuentos finales en función de las películas de envase. Los menores valores de μ (tasa de crecimiento microbiano) para el desarrollo de los microorganismos estudiados fueron observados en las muestras almacenadas en EVA SARAN EVA.Facultad de Ciencias Veterinaria

Clastosome: a subtype of nuclear body enriched in 19S and 20S proteasomes, ubiquitin, and protein substrates of proteasome.

Nuclear bodies represent a heterogeneous class of nuclear structures. Herein, we describe that a subset of nuclear bodies is highly enriched in components of the ubiquitin-proteasome pathway of proteolysis. We coined the term clastosome (from the Greek klastos, broken and soma, body) to refer to this type of nuclear body. Clastosomes contain a high concentration of 1) ubiquitin conjugates, 2) the proteolytically active 20S core and the 19S regulatory complexes of the 26S proteasome, and 3) protein substrates of the proteasome. Although detected in a variety of cell types, clastosomes are scarce under normal conditions; however, they become more abundant when proteasomal activity is stimulated. In contrast, clastosomes disappear when cells are treated with proteasome inhibitors. Protein substrates of the proteasome that are found concentrated in clastosomes include the short-lived transcription factors c-Fos and c-Jun, adenovirus E1A proteins, and the PML protein. We propose that clastosomes are sites where proteolysis of a variety of protein substrates is taking place

Advantageous Fungi against Parasites Transmitted through Soil

Although many fungal specimens are responsible for human and/or animal infection, other species are advantageous for preventing the infection by soil-transmitted zoonotic parasites. Infection occurs by the accidental ingestion of parasitic stages (cysts, oocysts, eggs, and larvae), their active penetration through the skin or through direct contact. Numerous species of helminths develop an external phase in the soil where the infective stages are attained, thus mammals become infected when grazing, drinking, or accidentally. Ectoparasites as ticks perform also in the soil the phase from egg to larva. Different soil saprophytic fungi that turn into predatory agents when parasitic stages are near have been isolated and described. These species are capable of destroying the pathogens or irreversibly decreasing their viability, providing thus a very interesting and sustainable tool to reduce environmental contamination by pathogenic agents. In the last year, a profound knowledge on the most appropriate fungal species, together with the proper way to disseminate them, has been acquired