3,737 research outputs found

    System dynamics modelling in systems biology and applications in pharmacology

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    El modelado matemático de sistemas biológicos complejos es uno de los temas clave en la Biología de Sistemas y varios métodos computacionales basados ​​en la simulación computarizada han sido aplicados hasta ahora para determinar el comportamiento de los sistemas no lineales. La Dinamica de Sistemas es una metodología de modelado intuitivo basada en el razonamiento cualitativo por el cual un modelo conceptual se puede describir como un conjunto de relaciones de causa y efecto entre las variables de un sistema. A partir de esta estructura, es posible obtener un conjunto de ecuaciones dinámicas que describan cuantitativamente el comportamiento del sistema. Centrándose en los sistemas farmacológicos, el modelado compartimental a menudo se utiliza para resolver un amplio espectro de problemas relacionados con la distribución de materiales en los sistemas vivos en la investigación, el diagnóstico y la terapia en todo el cuerpo, los órganos y los niveles celulares. En este artículo presentamos la metodología de modelado de Dinámica del Sistema y su aplicación al modelado de un modelo compartimental farmacocinético-farmacodinámico del efecto de profundidad anestésica en pacientes sometidos a intervenciones quirúrgicas, derivando un modelo de simulación en el entorno de simulación orientada a objetos OpenModelica. La Dinamica de Sistemas se puede ver como una herramienta educativa poderosa y fácil de usar y en la enseñanza de Biología de Sistemas.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Notas sobre la actual regulación de las tasas y precios públicos

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    PT-symmetry broken by point-group symmetry

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    We discuss a PT-symmetric Hamiltonian with complex eigenvalues. It is based on the dimensionless Schr\"{o}dinger equation for a particle in a square box with the PT-symmetric potential V(x,y)=iaxyV(x,y)=iaxy. Perturbation theory clearly shows that some of the eigenvalues are complex for sufficiently small values of a|a|. Point-group symmetry proves useful to guess if some of the eigenvalues may already be complex for all values of the coupling constant. We confirm those conclusions by means of an accurate numerical calculation based on the diagonalization method. On the other hand, the Schr\"odinger equation with the potential V(x,y)=iaxy2V(x,y)=iaxy^{2} exhibits real eigenvalues for sufficiently small values of a|a|. Point group symmetry suggests that PT-symmetry may be broken in the former case and unbroken in the latter one

    Feeling the music: Deaf people breaking the sound barrier

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    Este trabajo es parte de la Tesis Doctoral “Sentir la Música. Caminos de Realización Musical en Personas Sordas desde la perspectiva de la Justicia Social” que se realiza en el Grupo de Investigación Gice (Cambio Educativo para la Justicia Social) de la Facultad de Formación del Profesorado y Educación de la Universidad Autónoma de MadridEn esta investigación en marcha, partimos de un marco teórico en el que se plantea la Educación Musical como herramienta para el avance en Justicia Social. Desde el enfoque de Justicia Social en tres dimensiones que proponen Murillo y Hernández-Castilla (2011); Redistribución, Reconocimiento y Participación, se estructura una propuesta que desafía a los cánones tradicionales, apoyándose en las líneas pedagógicas más importantes de la Educación Musical del siglo XX y las más novedosas tanto de Música para la Justicia Social como de Música y Personas Sordas. Este estudio de enfoque cualitativo cuenta con la importante participación de personas sordas que nos están proporcionando una información clave para comprender cómo sienten la música, cómo son capaces de disfrutar aprendiendo y haciendo música y qué factores dificultan o impiden ese desarrollo musical. Se ha realizado una entrevista a cuatro personas sordas de diferente perfil sociodemográfico y en una segunda fase se ha aplicado un programa de formación musical a un grupo de personas sordas elaborado en base a la información aportada por el marco teórico y las entrevistas. Estos hallazgos nos aportan importantes datos para diseñar un programa de formación musical para personas sordas de acuerdo las características específicas de este colectivoIn this ongoing research, we start from a theoretical framework in which Musical Education is proposed as a tool for advancement in Social Justice. From the Social Justice approach in three dimensions proposed by Murillo and Hernández-Castilla (2011); Redistribution, Recognition and Participation, a proposal that defies the traditional canons, is based on the most important pedagogical lines of Music Education of the 20th century and the most innovative of Music for Social Justice as well as Music and Deaf People. This qualitative study has the important participation of deaf people who are providing us with key information to understand how they feel about music, how they are able to enjoy learning and making music and what factors make it difficult or impossible for them to develop. An interview was conducted with four deaf people of different sociodemographic profile and in a second phase a musical training program was applied to a group of deaf people based on the information provided by the theoretical framework and interviews. These findings provide us with important data for designing a musical training program for deaf people according to the specific characteristics of this grou

    Efficient solution of optimal multimarket electricity bid models

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    Short-term electricity market is made up of a sequence of markets, that is, it is a multimarket enviroment. In the case of the Iberian Energy Market the sequence of major short-term electricity markets are the day-ahead market, the ancillary service market or secondary reserve market (henceforth reserve market), and a set of six intraday markets. Generation Companies (GenCos) that participate in the electricity market could increase their benefits by jointly optimizing their participation in this sequence of electricity markets. This work proposes a stochastic programming model that gives the GenCo the optimal bidding strategy for the day-ahead market (DAM), which considers the benefits and costs of participating in the subsequent markets and which includes both physical futures contracts and bilateral contracts.Peer ReviewedPostprint (published version

    Mantos inducidos por microbialitas en sedimentos siliciclásticos plio-cuaternarios? del NO de Iberia

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    Microbial mats are organo-sedimentary deposits formed by bacteria that trap or synthesize certain chemical elements. This type of activity gives rise to the formation of lamellar and/or columnar bioconstructions (stromatolites) and/or concentric structures (oncolites and thrombolites). The study of microbial mats used to be restricted mainly to marine and coastal environments related to the formation of ancient carbonate sediments (Palaeozoic/Proterozoic), and/or extreme conditions in hypersaline environments. However, in recent years, the presence of these forms has been identified in continental siliciclastic rocks and sediments with a temporal distribution that reaches into modern times. In this study, several levels of ferruginous crusts associated with microbial activity are found, interspersed in a Cenozoic deposit located in the province of Zamora. This deposit consists of concentric, laminated iron structures filled with silt, interspersed throughout a clayey-silt layer of variegated colors which shows signs of bioturbation and desiccation due to fluid escape. These findings allow the inference of the sedimentary and climatic conditions responsible for the growth and preservation of microbial mats in the siliciclastic sediments of the north-western edge of the Duero BasinLos mantos microbiales constituyen depósitos organosedimentarios formados por bacterias que atrapan o sintetizan determinados elementos químicos. Este tipo de actividad da lugar a la formación de estructuras laminares y/o columnares (estromatolitos) y/o concéntricas (oncolitos y trombolitos). Su estudio, por tanto, quedaba reducido principalmente a ambientes marinos y litorales relacionados con la formación de sedimentos carbonatados de edad muy antigua (Paleozoico/ Proterozoico), y/o condiciones extremas en ambientes hipersalinos. Sin embargo, en los últimos años, se ha identificado la presencia de estas formas en rocas y sedimentos de afinidad continental y carácter siliciclástico, que se extienden temporalmente hasta la actualidad. En este estudio, se presenta el hallazgo de varios niveles de costras ferruginosas asociadas a la actividad microbiana, intercalados en un depósito cenozoico de la provincia de Zamora. Se trata de una serie de niveles caracterizados por la presencia de capas ferruginosas laminadas y concéntricas, constituidas por limos que aparecen en el techo y muro de un nivel arcilloso-limoso de colores abigarrados y signos de bioturbación y desecación por escape de fluidos. Este singular hallazgo permite establecer las condiciones sedimentarias y climáticas responsables del crecimiento y conservación de mantos microbianos en sedimentos siliciclásticos del borde noroccidental de la cuenca del Duer

    Electrochemical study on an activated carbon cloth modified by cyclic voltammetry with polypyrrole/anthraquinone sulfonate and reduced graphene oxide as electrode for energy storage

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    [EN] This work describes a two-step procedure for the electrochemical coating of reduced graphene oxide (RGO) and polypyrrole anthraquinone sulfonate (PPyAQS) onto an activated carbon cloth (ACC) by cyclic voltammetry (CV). The textile samples were characterized by CV, electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge measurements using a sandwich-type (electrode/separator/electrode) cell designed to operate in three or two-electrode configurations. The presence of RGO onto the ACC surface optimized the electrosynthesis of PPyAQS and reinforced the stability of the polymer with the number of charge/discharge cycles. A retention capacity of 90% after 100 charge-discharge cycles together with an energy density of 7.8¿×¿10¿4¿W¿h¿cm¿2 at a power density of 1.8¿×¿10¿3¿W¿cm¿2 were obtained for the ACC/RGO/PPyAQS sample. The analyses by field emission scanning electron microscopy (FESEM) showed the RGO veils-like and PPyAQS glomerular structures covering the ACC-fibers. The Fourier transform infrared spectroscopy (FTIR) analyses not only detected the presence of PPy and AQS, but also, the changes in the molecular structure of PPyAQS, depending on its oxidation state, as consequence of the redox reactions occurred in the charge/discharge processes in the two-electrode cell.The authors wish to acknowledge to Chemviron Carbon who kindly donated the ZORFLEX® activated carbon fabric. The authors wish to thank the Spanish Agencia Estatal de Investigación de Economía (AEI) and European Union (FEDER funds) for the financial support (contract MAT2016-77742-C2-1-P). Tim Vickers is gratefully acknowledged for help with the English revision. Electron Microscopy Service of the UPV (Universitat Politècnica de València) is gratefully acknowledged for help with FESEM characterization.Fernández Sáez, J.; Bonastre Cano, JA.; Molina Puerto, J.; Cases, F. (2018). Electrochemical study on an activated carbon cloth modified by cyclic voltammetry with polypyrrole/anthraquinone sulfonate and reduced graphene oxide as electrode for energy storage. European Polymer Journal. 103:179-186. https://doi.org/10.1016/j.eurpolymj.2018.04.018S17918610

    First report of caprine abortions due to Chlamydia abortus in Argentina.

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    Infectious abortions of goats in Argentina are mainly associated with brucellosis and toxoplasmosis. In this paper, we describe an abortion outbreak in goats caused by Chlamydia abortus. Seventy out of 400 goats aborted. Placental smears stained with modified Ziehl-Neelsen stain showed many chlamydia-like bodies within trophoblasts. One stillborn fetus was necropsied and the placenta was examined. No gross lesions were seen in the fetus, but the inter-cotyledonary areas of the placenta were thickened and covered by fibrino-suppurative exudate. The most consistent microscopic finding was found in the placenta and consisted of fibrinoid necrotic vasculitis, with mixed inflammatory infiltration in the tunica media. Immunohistochemistry of the placenta was positive for Chlamydia spp. The results of polymerase chain reaction targeting 23S rRNA gene performed on placenta were positive for Chlamydia spp. An analysis of 417 amplified nucleotide sequences revealed 99% identity to those of C. abortus pm225 (GenBank AJ005617) and pm112 (GenBank AJ005613) isolates. To the best of our knowledge, this is the first report of abortion associated with C. abortus in Argentina
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