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Scenario-based earthquake simulations at regional scales hold the promise in advancing the state-of-the-art in seismic risk assessment studies. In this study, a computational workflow is presented that combines (i) a broadband Green's function-based fault-rupture and ground motion simulation-herein carried out using the "UCSB (University of California at Santa Barbara) method", (ii) a three-dimensional physics-based regional-scale wave propagation simulation that is resolved at fmax=11.2 Hz, and (iii) a local soil-foundation-structure finite element analysis model. These models are interfaced with each other using the domain reduction method. The innermost local model-implemented in ABAQUS-is additionally enveloped with perfectly matched layer boundaries that absorb outbound waves scattered by the structures contained within it. The intermediate wave propagation simulation is carried out using Hercules, which is an explicit time-stepping finite element code that is developed and licensed by the CMU-QUAKE group. The devised workflow is applied to a 80x40x40 km3 region on the European side of Istanbul, which was modeled using detailed soil stratigraphy data and realistic fault rupture properties, which are available from prior microzonation surveys and earthquake scenario studies. The innermost local model comprises a chevron-braced steel frame building supported by a shallow foundation slab, which, in turn, rests atop a three-dimensional soil domain. To demonstrate the utility of the workflow, results obtained using various simplified soil-structure interaction analysis techniques are compared with those from the detailed direct model. While the aforementioned demonstration has a limited scope, the devised workflow can be used in a multitude of ways, for example, to examine the effects of shallow-layer soil nonlinearities and surface topography, to devise site- and structure-specific seismic fragilities, and for calibrating regional loss models, to name a few.

Colonia Caroya, situada 50 km al Norte de la provincia de Córdoba, se caracteriza por la producción de cultivos intensivos: viñedos, frutales, hortícolas y oleaginosas. Estas producciones se llevan a cabo en fincas insertas en el área urbana y periurbana, son sostenidas en su mayoría por familias, y las mismas se destinan fundamentalmente al mercado regional y una parte menor a nivel nacional y exportación. En general la condición sanitaria con relación a patógenos sistémicos no es controlada, y a su vez, las parcelas, son tratadas con agroquímicos para el control de plagas y malezas, lo que genera riesgo de deriva y la posibilidad de afectar cultivos vecinos y/o la salud de los habitantes próximos a dichas parcelas. La experiencia en la zona, se enfocó a ubicar fincas de frutales y vides, para identificar problemas sanitarios debido a la presencia de patógenos sistémicos. En diversas fincas se evaluaron in situ síntomas y daños en plantas, y se tomaron muestras para su análisis con pruebas de laboratorio. Como resultado del trabajo se pretende lograr calidad sanitaria, para las plantas de partida de huertos y viñedos, y generar pautas de manejo, para reducir el uso de agroquímicos y promover una conducta sostenible para producciones de alto rendimiento. Instituto de Patología Vegetal Fil: Dal Zotto, Angelica. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina Fil: Cordes, Diego Darío. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi. Agencia De Extensión Rural Jesús María; Argentina Fil: Grion, Adolfo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi. Agencia De Extensión Rural Jesús María; Argentina Fil: Pastor, Silvina Estela. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina Fil: Tolocka, Patricia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina Fil: Fernandez, Franco Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina Fil: Taborda, R. Universidad Nacional de Córdoba. Facultad Ciencias Agropecuarias; Argentina Fil: Haelterman, Raquel Mercedes. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina Fil: Conci, Luis Rogelio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentina

In this article an investigation is presented, where factors influencing temperature and humidity ariables in a temperature controlled chamber are analyzed. The objective of this study is to determine whether the humidity can be controlled independently of temperature in order to implement a change in the system to stabilize the relative humidity. After showing the theoretical background, the changes to be made in the chamber and the measurements that demonstrate improvements in terms of stability of relative humidity are shown.

We study the presence of multiple structure-soil-structure interaction effects in idealized building clusters during earthquakes, their effect on the ground motion, and how individual buildings interact with the soil and with each other. We seek to characterize, through a parametric approach, the coupling effects between the soil, the foundation, and the structural response of the buildings, including torsion, in the presence of surrounding structures. We simulate the ground motion of a historical earthquake and focus on the response of simplified building models located on soft soil. Throughout our analysis, we use as reference the response of an isolated building model with and without soil-structure interaction and with and without torsion. This allows us to separate the contribution of the different factors and distinguish between the individual soil-structure interaction characteristics of the single building, and those product of coupling and structure-soil-structure interaction in the presence of multiple surrounding buildings. Numerical results show that structure-soil-structure interaction effects vary with the number and dynamic properties of the buildings, their separation, and the impedance with respect to the soil. Our results indicate that torsional effects may also play a role in the coupling effects between the soil and the structure, and modify the level of interaction between multiple structures. Interaction effects appear as an increased spatial variability of the ground motion; and significant reductions in the buildings' base motion at frequencies above the natural frequencies of the building-foundation systems. In turn, the changes on the ground motion and in the effective excitation at the base of the buildings also modify the structural response of the buildings, including the effects of torsion in structurally asymmetric buildings.

Introduction: the availability of transplantable livers is not sufficient to fulfill the current demand for grafts, with the search for therapeutic alternatives having generated different lines of research, one of which is the use of decellularized three-dimensional biological matrices and subsequent cell seeding to obtain a functional organ. Objective: to produce a decellularization protocol from rabbit liver to generate a three-dimensional matrix. Methods: a combination of physical, chemical (Triton X-100 and SDS) and enzymatic agents to decellularize rabbit livers was used. After 68 h of retrograde perfusion, a decellularized translucent matrix was generated. To evaluate if the decellularization protocol was successful, with the extracellular matrix being preserved, we carried out histological (light microscopy and scanning electron microscopy) and biochemical (DNA quantification) studies. Results: the decellularization process was verified by macroscopic observation of the organ using macroscopic staining, which revealed a correct conservation of bile and vascular trees. A microscopic observation corroborated these macroscopic results, with the hematoxylin-eosin staining showing no cells or nuclear material and the presence of a portal triad. Wilde's staining demonstrated the conservation of reticulin fibers in the decellularized matrix. In addition, scanning electron microscopy revealed a preserved Glisson's capsule and a decellularized matrix, with the DNA quantification being less than 10 % in the decellularized liver compared to control. Finally, the time taken to develop the decellularization protocol was less than 96 hours. Conclusions: the proposed decellularization protocol was correct, and was verified by an absence of cells. The hepatic matrix had preserved vascular and bile ducts with a suitable three-dimensional architecture permitting further cell seeding. Introducción: el número de hígados trasplantables es insuficiente para satisfacer las necesidades actuales de la demanda de injerto. La búsqueda de alternativas terapéuticas ha generado diferentes líneas de investigación, una de ellas es la utilización de matrices biológicas tridimensionales descelularizadas y la posterior siembra celular para obtener un órgano funcional. Objetivo: obtención de un protocolo de descelularización de hígado de conejo que genere una matriz hepática tridimensional. Métodos: una combinación de detergentes (Triton X-100 y SDS), agentes físicos y enzimáticos se utilizaron para descelularizar hígados de conejo. Los órganos se pefundieron en forma retrógrada con distintos agentes químicos durante 68 horas. Luego los hígados se examinaron por técnicas morfológicas (microscopía óptica y electrónica de barrido) y bioquímicas (cuantificación de ADN) para evaluar una correcta descelularización así como la obtención de una matriz extracelular preservada. Resultados: la observación macroscópica del órgano permitió inferir la descelularización del mismo. Las tinciones macroscópicas utilizadas mostraron una correcta conservación de los árboles biliar y vascular. Por otro lado, la observación microscópica del hígado permitió corroborar los resultados macroscópicos observados, la tinción de hematoxilina-eosina mostró ausencia de células y de material nuclear así como la presencia de la tríada portal. La tinción de Wilde evidenció la conservación de las fibras de reticulina en la matriz descelularizada. Asimismo, la microscopía electrónica de barrido reveló una cápsula de Glisson conservada y la descelularización de la cuantificación de ADN fue inferior al 10 % en el hígado descelularizado con respecto al hígado control. Finalmente, el tiempo utilizado para la descelularización fue inferior a las 96 horas. Conclusiones: el protocolo de descelularización propuesto fue apropiado ya que se verificó una ausencia de células y una matriz hepática con conductos vasculobiliares conservados y con una arquitectura tridimensional adecuada para una futura siembra celular.

The main objective of this thesis is to build a framework for performing earthquake simulations capable of including nonlinear soil behavior and the presence of the built environment in highly heterogeneous basins, and to study their influence on the final response of the ground in large urban areas exposed to high seismic hazard. To this end, we use a finite elements approach and extend the capabilities of Hercules, the parallel octree-based earthquake simulator developed by the Quake Group at Carnegie Mellon. Nonlinear soil behavior is incorporated in ground motion simulations employing a rate-dependent plasticity approach to predict the nonlinear state of the material explicitly at every time step. The soil is modeled as a perfectly elastoplastic material. The presence of urban structures is modeled representing buildings as homogeneous blocks made up of the same type of hexahedral elements used in the mesh. These elements are generated automatically through a new set of application programming interfaces, which extend Hercules' meshing capabilities while preserving its core octree-based formulation. Both implementations are tested under realistic earthquake conditions in heterogeneous geological structures. In the case of nonlinear ground motion modeling, results indicate that soil nonlinearities greatly modify the ground response, confirming previous observations for deamplification effects and spatial variability, and evidencing three-dimensional basin effects not fully observed before. In turn, the presence of building clusters causes multiple soil-structure interaction phenomena that change both the near ground-motion and the individual performance of the buildings themselves. This substantiates the argument that in soft-soil basins may it not be longer valid to ignore the presence of neighboring structures. These new implementations represent important advances in computational seismology and help make a direct connection to subjects of interest in earthquake engineering. The analysis drawn from the applications presented here confirms aspects known from previous, though limited studies, and broadens our knowledge of the effects of nonlinear soil and the built environment on the ground motion due to earthquakes at a regional level not explored before.

Cuando se habla de un material que va a estar en contacto con alguna parte del cuerpo humano (biomaterial), el concepto va ligado indefectiblemente a la biocompatibilidad. La biocompatibilidad se describe como la cualidad que tiene un biomaterial de generar una respuesta biológica aceptable durante el tiempo y modo de contacto de una aplicación específica. La ausencia de rechazo de un implante o de un dispositivo por parte del organismo implica una aceptación tanto biológica, como química y mecánica. La norma internacional que regula esta importante propiedad es la norma ISO 10993, que en sus 20 partes indica los ensayos a realizar en función del tiempo y tipo de contacto del biomaterial con los tejidos del organismo vivo. La realización de estos ensayos del material, in-vitro e in-vivo, requiere de un laboratorio multidisciplinario especializado en los mismos, con incumbencia de profesionales de diferentes áreas, tanto de la medicina, como de la biología, veterinaria, química e ingeniería. La Facultad de Ciencias Exactas Físicas y Naturales (FCEFyN) de la Universidad Nacional de Córdoba (UNC), a través de la Cátedra de Biomateriales de la Carrera de Ingeniería Biomédica, ha planteado la necesidad de contar en el país con un laboratorio de evaluación de la biocompatibilidad, designando a tal fin a un grupo inicial de profesionales para comenzar a trabajar en el proyecto de creación y organización del mencionado laboratorio. Fil: Salvatierra, Nancy Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina Fil: Oldani, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Electrónica. Laboratorio de Investigación Aplicada y Desarrollo; Argentina Fil: Reyna, Laura. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Electrónica. Laboratorio de Investigación Aplicada y Desarrollo; Argentina Fil: Taborda, Ricardo Alberto Mario. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Electrónica. Laboratorio de Investigación Aplicada y Desarrollo; Argentina

La caracterización de cultivares de duraznero (Prunus persica (L) Batsch) se hace por medio de la descripción de caracteres agronómicos y morfológicos codificados por organizaciones internacionales, los cuales están fuertemente influenciados por el ambiente. Se han buscado métodos alternativos de caracterización y las isoenzimas han sido utilizadas por su independencia de las condiciones del ambiente, además de identificar individuos en etapas tempranas de su desarrollo. El objetivo del presente estudio es caracterizar cultivares de duraznero mediante el análisis isoenzimático de catecol oxidasas, fosfatasas ácidas, esterazas y peroxidazos en extractos de hojas. Los cultivares de duraznero analizados presentaron bajo polimorfismo isoenzimático, las esterazas caracterizaron diez cultivares, las catecol oxidasas un cultivar agrupándose el resto en cinco modelos, las fosfatasas ácidas caracterizaron dos cultivares agrupándose los otros en siete modelos y las peroxidazos formaron tres grupos. Ello puede explicarse ya que el duraznero es una especie autofértil y presenta una base genética muy reducida. Los evidentes límites discriminatorios de este tipo de análisis hacen que su aporte sea sólo complementario a los métodos de los caracteres agronómicos y morfológicos. Characterization of peach cultivars (Prunus persica (L) Batsh) was made by description of agronomical and morphological characters codified from international organizations, which are strongly affected by environmental conditions. Alternative methods of characterization have been searched, and isoenzymes have been used as independent of environmental conditions in addition to identify some individuals in early stages of development. The goal of this study is the peach cultivars characterization by isoenzymatic analysis of catecol oxidases, acid phosphatases, esterases and peroxidases within the leaf extracts. The peach cultivars analyzed have showed low isoenzymatic polymorphism. Ten cultivars were characterized by esterases while one cultivar by catecol oxidases. The remainder cultivars were grouped into five models. The acid phosphatases have characterized two cultivars; the remainder was grouped into seven models. The peroxidases formed three groups. This behavior can be explained since the peach is an autogamus species and it shows a very reduced genetic basis. The evident and discriminant restrictions of this type of analysis have got results that have been only a complementary form for the methods of agronomical and morphological characters.

Large-scale earthquake simulation requires source datasets which describe the highly heterogeneous physical characteristics of the earth in the region under simulation. Physical characteristic datasets are the first stage in a simulation pipeline which includes mesh generation, partitioning, solving, and visualization. In practice, the data is produced in an ad-hoc fashion for each set of experiments, which has several significant shortcomings including lower performance, decreased repeatability and comparability, and a longer time to science, an increasingly important metric. As a solution to these problems, we propose a new approach for providing scientific data to ground motion simulations, in which ground model datasets are fully materialized into octress stored on disk, which can be more efficiently queried (by up to two orders of magnitude) than the underlying community velocity model programs. While octrees have long been used to store spatial datasets, they have not yet been used at the scale we propose. We further propose that these datasets can be provided as a service, either over the Internet or, more likely, in a data center or supercomputing center in which the simulations take place. Since constructing these octrees is itself a challenge, we present three data-parallel techniques for efficiently building them, which can significantly decrease the build time from days or weeks to hours using commodity clusters. This approach typifies a broader shift toward science as a service techniques in which scientific computation and storage services become more tightly intertwined.

Tesis (DCI)--FCEFN-UNC, 2010 Estudia la implementación de dicho sistema, denominado sistema prototipo de ecografía acústica, a partir del estudio de los fenómenos de interacción acústica sísmica de un tipo de arena suelta como medio propagante de los múltiples ensayos realizados