Determination of groundwater flow based on temperature data

Desarrollo de una metodología de interpretación de datos de temperatura y de ensayos de calentamiento con fibra ópticaDifferent techniques have been used to measure the groundwater flow velocity but they are either too invasive or too inaccurate. In the present study two analytical solutions have been developed and tested to determine the unit discharge using heat as a tracer with an optical fiber. First, an analytical solution for the thermal response of the fluctuations of sea temperature has been developed and verified. The model considers a porous medium through which water flows and a boundary with prescribed temperature representing the fluctuations of the sea. The measuring point depth and the unit discharge define the solution. A methodology is proposed to compute the unit discharge and the depth of the measuring point. Second, an analytical approach is developed for the thermal dissipation with advection from a line source. The asymptotic behavior and the final temperature for the steady state are described. Using a FEM based in Kratos, a sensitivity analysis has been carried out to understand the dependence on the unit discharge, the thermal properties of the cable and the soil. Three stages have been defined: the initial heating governed by the cable properties, the logarithmic heating defined by the thermal conductivity of the soil and the steady state defined by the unit discharge and the previous parameters. A methodology has been also proposed to estimate the unit discharge and the thermal conductivity of the soil from thermal dissipation dataPara medir el flujo de agua subterránea se han utilizado múltiples técnicas pero resultan ser o muy invasivas o poco precisas. En el presente estudio, se han desarrollado y verificado dos soluciones analíticas para determinar el flujo subterráneo usando el calor como trazador con la ayuda de la fibra óptica. En primer lugar, se ha desarrollado y verificado una solución analítica para la respuesta térmica de las fluctuaciones de la temperatura del mar. La profundidad del punto de medida y el flujo subterráneo determinan la solución. Se propone una metodología para calcular el flujo subterráneo y la profundidad del punto de medida. En segundo lugar, se ha desarrollado una solución analítica para la disipación térmica con advección de una fuente lineal. Se han descrito el comportamiento asintótico y la temperatura final para el estado estacionario. Con la ayuda de un programa de elementos finitos basado en Kratos, se ha llevado a cabo un análisis de sensibilidad mostrando la dependencia con el flujo, las propiedades térmicas del cable y del suelo. Se han definido tres fases: el calentamiento inicial gobernado por las propiedades del cable, el calentamiento logarítmico definido por la conductividad térmica del suelo y el estado estacionario determinado por el flujo y las propiedades precedentes. Se ha propuesto una segunda metodología para estimar el flujo subterráneo y la conductividad térmica del suelo a partir de datos de disipación térmica.Per mesurar el flux d’aigua subterrània s’han utilitzat diverses tècniques però són molt invasives o poc precises. En el present estudi, s’han desenvolupat i verificat dues solucions analítiques per a determinar el flux subterrani utilitzant la calor com a traçador amb l’ajuda de la fibra òptica. En primer lloc, s’ha desenvolupat i verificat una solució analítica per a la resposta tèrmica de les fluctuacions de la temperatura del mar. La profunditat del punt de mesura i el flux subterrani determinen la solució. Es proposa una metodologia per a calcular el flux subterrani i la profunditat del punt de mesura. En segon lloc, s’ha desenvolupat una solució analítica per a la dissipació tèrmica amb advecció d’una font lineal. S’han descrit el comportament asimptòtic i la temperatura final per a l’estat estacionari. Amb l’ajuda d’un programa d’elements finits basat en Kratos, s’ha dut a terme una anàlisi de sensibilitat mostrant la dependència amb el flux: l’escalfament inicial governat per les propietats del cable, l’escalfament logarítmic definit per la conductivitat tèrmica del sol i l’estat estacionari determinat pel flux i les propietats precedents. S’ha proposat una segona metodologia per a estimar el flux subterrani i la conductivitat tèrmica del s`ol a partir de dades de dissipació tèrmica

Distribution of dopant ions around poly(3,4-ethylenedioxythiophene) chains: a theoretical study

The effect of counterions and multiple polymer chains on the properties and structure of poly(3,4-ethylenedioxythiophene) (PEDOT) doped with ClO4- has been examined using density functional theory (DFT) calculations with periodic boundary conditions (PBCs). Calculations on a one-dimensional periodic model with four explicit polymer repeat units and two ClO4- molecules indicate that the latter are separated as much as possible, with the salt structure and band gap obtained from such ClO4- distribution being in excellent agreement with those determined experimentally. On the other hand, DFT calculations on periodic models that include two chains indicate that neighboring PEDOT chains are shifted along the molecular axis by a half of the repeat unit length, with dopant ions intercalated between the polymer molecules acting as cement. In order to support these structural features, classical molecular dynamics (MD) simulations have been performed on a multiphasic system consisting of 69 explicit PEDOT chains anchored onto a steel surface, explicit ClO4- anions embedded in the polymer matrix, and an acetonitrile phase layer onto the polymer matrix. Analyses of the radial distribution functions indicate that the all-anti conformation, the relative disposition of adjacent PEDOT chains and the distribution of ClO4- dopant ions are fully consistent with periodic DFT predictions. The agreement between two such different methodologies allows reinforcing the microscopic understanding of the PEDOT film structure.Peer ReviewedPostprint (author's final draft

Effects of hydroxyapatite (0001) Ca2+/Mg2+ substitution on adsorbed D-ribose ring puckering

Advanced Molecular Dynamics (MD) simulation protocols have been used to assess the ring puckering of cyclic D-ribose when the sugar is adsorbed on the most stable (0001) facet of calcium hydroxyapatite (HAp). In addition, sugar¿mineral interactions, which are crucial for transfection processes and prebiotic chemistry, have been studied for systems in which the Ca2+ ions of the above mentioned HAp facet were totally or partially replaced by Mg2+. The latter replacement is spatially and quantitatively limited and has been found to cause important alterations in the conformational behavior of D-ribose that are similar to those suffered in hairpin RNA from A to B helical structures. Accordingly, replacement of Ca2+ by Mg2+ has a dramatic effect on the functionality of the nucleic acid. These changes have been related to both the substitution site on the surface and the amount of ions. Our results show that when replacement by Mg2+ occurs in OH--coordinated Ca2+ ions, Mg2+¿D-ribose interactions are strong enough to prevent the interactions between the hydroxyl groups of the sugar and the remaining Ca2+ ions.Peer ReviewedPostprint (published version

Identificación de necesidades de monitoreo de ciberseguridad enfocado en el segmento PyMEs

Habiendo relevado las necesidades comunes de las organizaciones respecto de Ciberseguridad, con foco en el rubro PyME, se procederá a clarificar los recursos, metodologías y know-how necesario para crear un Centro de Operaciones de Ciberseguridad que permita monitorear aspectos de Seguridad Informática de organizaciones, adaptado a la realidad de cada tipo de organización, por lo que se plantearán diferentes casos de uso.Sociedad Argentina de Informática e Investigación Operativ

Identificación de necesidades de monitoreo de ciberseguridad enfocado en el segmento PyMEs

Habiendo relevado las necesidades comunes de las organizaciones respecto de Ciberseguridad, con foco en el rubro PyME, se procederá a clarificar los recursos, metodologías y know-how necesario para crear un Centro de Operaciones de Ciberseguridad que permita monitorear aspectos de Seguridad Informática de organizaciones, adaptado a la realidad de cada tipo de organización, por lo que se plantearán diferentes casos de uso.Sociedad Argentina de Informática e Investigación Operativ

Fortalecimiento en la seguridad de web services para aplicaciones críticas

Reconociendo a las propiedades de la Seguridad de la Información (confidencialidad, integridad y disponibilidad) como elementos esenciales de cualquier transferencia de datos, haciendo foco en el conjunto de protocolos y estándares utilizados para intercambiar datos entre aplicaciones web, es decir, Web Services, para el presente trabajo definimos el objetivo general de asegurar dichas comunicaciones, teniendo en consideración que la información intercambiada es igual o más crítica y confidencial que la transferida entre sistemas informáticos con la interacción humana. Vamos a definir a las Aplicaciones Críticas, aquellas que se encuentran corriendo dentro de las Infraestructuras Críticas, siendo éstas las definidas por la Oficina Nacional de Tecnología de Información (ONTI), dependiente de la Jefatura de Gabinete de Ministros. En este marco es que los aspectos de seguridad cobran una relevancia superior y por tanto los esfuerzos para segurizar los sistemas deben ser extremos. Bajo este objetivo general, se definieron lineamientos particulares para efectuar lo que denominamos “hardening de seguridad de Web Services”, lo que implica la conformación de una guía mediante la cual se establecen medidas de seguridad que ayudan a disminuir los riesgos de violación de las propiedades de seguridad mencionadas.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Fortalecimiento en la seguridad de web services para aplicaciones críticas

Reconociendo a las propiedades de la Seguridad de la Información (confidencialidad, integridad y disponibilidad) como elementos esenciales de cualquier transferencia de datos, haciendo foco en el conjunto de protocolos y estándares utilizados para intercambiar datos entre aplicaciones web, es decir, Web Services, para el presente trabajo definimos el objetivo general de asegurar dichas comunicaciones, teniendo en consideración que la información intercambiada es igual o más crítica y confidencial que la transferida entre sistemas informáticos con la interacción humana. Vamos a definir a las Aplicaciones Críticas, aquellas que se encuentran corriendo dentro de las Infraestructuras Críticas, siendo éstas las definidas por la Oficina Nacional de Tecnología de Información (ONTI), dependiente de la Jefatura de Gabinete de Ministros. En este marco es que los aspectos de seguridad cobran una relevancia superior y por tanto los esfuerzos para segurizar los sistemas deben ser extremos. Bajo este objetivo general, se definieron lineamientos particulares para efectuar lo que denominamos “hardening de seguridad de Web Services”, lo que implica la conformación de una guía mediante la cual se establecen medidas de seguridad que ayudan a disminuir los riesgos de violación de las propiedades de seguridad mencionadas.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Hierarchical self-assembly of di-, tri- and tetraphenylalanine peptides capped with two fluorenyl functionalities: from polymorphs to dendrites

Homopeptides with 2, 3 and 4 phenylalanine (Phe) residues and capped with fluorenylmethoxycarbonyl and fluorenylmethyl esters at the N-terminus and C-terminus, respectively, have been synthesized to examine their self-assembly capabilities. Depending on the conditions, the di-and triphenylalanine derivatives self-organize into a wide variety of stable polymorphic structures, which have been characterized: stacked braids, doughnut-like shapes, bundled arrays of nanotubes, corkscrew-like shapes and spherulitic microstructures. These highly aromatic Phe-based peptides also form incipient branched dendritic microstructures, even though they are highly unstable, making their manipulation very difficult. Conversely, the tetraphenylalanine derivative spontaneously self-assembles into stable dendritic microarchitectures made of branches growing from nucleated primary frameworks. The fractal dimension of these microstructures is similar to 1.70, which provides evidence for self-similarity and two-dimensional diffusion controlled growth. DFT calculations at the M06L/6-31G(d) level have been carried out on model beta-sheets since this is the most elementary building block of Phe-based peptide polymorphs. The results indicate that the antiparallel beta-sheet is more stable than the parallel one, with the difference between them growing with the number of Phe residues. Thus, the cooperative effects associated with the antiparallel disposition become more favorable when the number of Phe residues increases from 2 to 4, while those of the parallel disposition remained practically constant.Peer ReviewedPostprint (author's final draft

Types of Intelligence and Academic Performance: A Systematic Review and Meta-Analysis

Abstract: The concept of intelligence has been extensively studied, undergoing an evolution from a unitary concept to a more elaborate and complex multidimensional one. In addition, several research studies have focused their efforts for decades on the study of intelligence as a predictor of academic performance of students at different educational stages, being a stable and highly relevant predictor along with other variables such as executive functions, social context, culture or parental guardianship. Thus, the present study, based on a systematic review and meta-analysis, includes 27 studies with a total sample of 42,061 individuals. The main objective was to analyse the relationship between intelligence and academic performance using different predictive models that include moderating variables such as country of origin, type of intelligence, gender and age. The findings of this research highlight the significant, positive and moderate relationship between intelligence and academic performance (r = 0.367; p < 0.001), highlighting the predictive capacity on school performance when the type of intelligence (general and implicit; 35%) or the country of origin (45%) is taken as a moderating variable, with the explanatory models on age or sex not being significant. Therefore, it can be concluded that intelligence, in addition to being a good predictor of academic performance, is influenced depending on the type of intelligence or theoretical model taken as a reference, and also depending on the country or culture of origin

Diversity and hierarchy in supramolecular assemblies of triphenylalanine: from laminated helical ribbons to toroids

Microstructures from small phenylalanine-based peptides have attracted great attention lately because these compounds are considered to be a new class of tunable materials. In spite of the extensive studies on uncapped diphenylalanine and tetraphenylalanine peptides, studies on the self-assembly of uncapped triphenylananine (FFF) are very scarce and nonsystematic. In this work, we demonstrate that FFF assemblies can organize in a wide number of well-defined supramolecular structures, which include laminated helical-ribbons, leaflike dendrimers, doughnut-, needle-, and flower-shapes. These organizations are produced by the attractive or repulsive interactions between already formed assemblies and therefore can be controlled through the choice of solvents used as the incubation medium. Thus, the formation of the desired supramolecular structures is regulated through the protonation/deprotonation of the terminal groups, the polarity of the incubation medium, which affects both peptide···solvent interactions and the cavity solvation energy (i.e., solvent···solvent interactions), and the steric interactions between own assemblies that act as building blocks. Finally, the ß-sheet disposition in the latter structural motifs has been examined using both theoretical calculations and Fourier transform infrared spectroscopy. Results indicate that FFF molecules can adopt both parallel and antiparallel ß-sheets. However, the former one is the most energetically favored because of the formation of p–p stacking interactions between the aromatic rings of hydrogen-bonded strands.Preprin