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The seismic characterization of fractured geological formations is of importance for a wide range of applications throughout the Earth, environmental and engineering sciences, such as, for example, hydrocarbon exploration and production, CO­­2 sequestration, monitoring of enhanced geothermal reservoirs, nuclear waste storage, and tunneling operations. Seismic methods are indirect in nature, and, hence, comprehensive modelling techniques are required to translate corresponding observations into rock physical properties. In this regard, numerous works have employed the theoretical framework of poroelasticity in order to explore the seismic response of particularly complex and elusive parameters of fluid-saturated fracture networks, such as their fracture density and interconnectivity. This is motivated by the fact that poroelasticity allows to account for fluid pressure diffusion effects between connected fractures as well as between fractures and their embedding background. Fluid pressure diffusion prevails when zones of contrasting compliance are traversed by a seismic wave, as this results in pressure gradients, which induce oscillatory fluid flow and, consequently, energy dissipation. This form of energy dissipation has a significant impact on seismic velocity dispersion, attenuation, and anisotropic characteristics, which are key seismic observables. While a wide range of approximations are employed to represent fracture properties in order to compute the seismic response of formations, they do tend to inherently ignore the complex interrelationships between the lengths, compliances, apertures, and permeabilities of fractures remains, as of yet, unaccounted for. In this work, we seek to alleviate this in combination with a poroelastic modelling approach to explore how length-dependent fracture scaling characteristics affect the effective seismic properties of fractured rocks. We start by revisiting canonical models with two orthogonally intersecting fractures of different lengths to analyze the interactions occurring when fractures are affected by a seismic wavefield. We then proceed to explore how scaling relations affect these results. Finally, we consider fracture networks with realistic stochastic length distributions, for which we compare the effective seismic response with and without the proposed length-dependent scaling of the fracture characteristics. Our results demonstrate that the scaling of fracture properties does indeed have a significant effect on the seismic response, as it dramatically reduces the contribution of smaller fractures to fluid pressure diffusion between connected fractures, which, in turn, affects the overall seismic characteristics of the formation.

La epidemia por COVID-19, causada por el nuevo coronavirus-2 del síndrome respiratorio agudo severo (SARS-CoV-2) ha enfrentado al equipo de salud a un abanico de presentaciones clínicas y alteraciones de las funciones órganicas a las que diagnosticar y tratar. Dentro de estas se encuentra la disfunción tiroidea. En este reporte se presenta el caso de una paciente con taquicardia persistente luego de pasado el cuadro de COVID-19, que derivó en múltiples consultas hasta que se arribó al diagnóstico de tirotoxicosis de etiología autoinmune. La tirotoxicosis asociada a COVID-19 es infrecuente, pero agrega morbilidad a la convalecencia de los pacientes, por lo que su sospecha clínica y diagnóstico rápido serían beneficiosos.

A major challenge for digital video storage or traffic was that the original or uncompressed video required a lot of digital information. Therefore, it was necessary to carry out some compression process to transmit or store digitized video with the least amount of bits possible. The word compression, as a synonym for coding, refers to the device called codec (coder-decoder), which is commonly used in multimedia environments. Since the 1990s, approximately every nine years, the development of a new standard is concluded, and each new codec is almost twice as efficient as the previous one. The newer compression methods are much more complex and more sophisticated than the previous ones, but they demand much more computational power. This paper presents a comparative study of codec behavior by experimentation. A balanced combination of established standards and some newer ones for contrast were selected. It used a trailer of the movie Star Trek, and a video of an Adobe Connect videoconference, of the same duration. The videos were encoded in H.264, H.265, VP8 and Theora. It proposes an experiment in a real laboratory, with wireless clients working in the IEEE 802.11ac standard and IPv6. The conclusions of the work will help to determine the adequate management of similar real or simulated networks.

The increasing number of multimedia users on networks entails an exponential growth in the demand for bandwidth. End users and applications pose increasing demands on Traffic Engineering, QoS and QoE of video-based products. This paper reports an experimental study of multicast video traffic in an actual laboratory network, in a controlled environment, as a testbed, with IEEE 802.11ac IPv6 wireless clients. Experiments were conducted using a Star Trek movie trailer. Alternatively, for contrast purposes, a video of equal length taken from a video conference on Adobe Connect was used. The videos were coded using H.264, H.265, VP8 and Theora. This study is the sequel to an earlier experimental study conducted on video traffic for wired networks. The main conclusions seek to guide and help simulation analysts, network administrators, designers and planners in determining the best settings to take into account in order to properly manage similar networks, efficiently using available resources without compromising the expected quality and performance levels.

This work presents a quantitative experimental study of multicast video traffic in a Wi-Fi network of a real laboratory as test bed, with a topology in wired and wireless networks with wireless clients working in the IEEE 802.11ac standard. For experimental work IPv6, the Server and Client Software FFmpeg and the traffic analyzer WireShark were used. The videos were encoded in H.264, H.265, VP8 and Theora, to assess and understand the impact of different codecs on network traffic. And the experiments were carried out using a trailer of the movie Star Trek, and alternately for contrast, a video of a videoconference using Adobe Connect, of the same duration and resolution. This work is a continuation of experience made on wired networks for video traffic with codecs H261, H263 and H264 using IPv4. Although this work presents a new scenario of Wi-Fi experimentation and a new methodology for the contrast of videos using IPv6.

This paper shows a solution to develop Collaborative Massive Open On-Line Courses (MOOC) among universities of three Latin American countries and universities of three European countries by the definition of a Standardization Guide as result of the DIEGO project. This guide is necessary to coordinate different actors to deliver a coordinate MOOC.

Ponencias y experiencias empresa de las 23 Jornadas de Archivos Universitarios, 21-23 de junio de 2017, A Coruña. ISBN: 978-84-9749-680-3. DOI https://doi.org/10.17979/spudc.9788497496803 [Resumen] El libro reúne las ponencias y experiencias empresa presentadas, además de las conclusiones aprobadas, en las 23 Jornadas de Archivos Universitarios, celebradas entre el 21 y 23 de junio de 2017 en A Coruña. Las ponencias tratan varios de los principales aspectos que afectan a la implantación de la administración digital y el consecuente establecimiento del archivo electrónico: el marco jurídico-administrativo introducido por las leyes estatales 39 y 40 de 2015; la introducción de modelos conceptuales de descripción archivística; y la preservación digital a largo plazo, así como la dificultad para calcular sus costes. Además, se tratan los casos concretos de la implantación de la administración y archivo electrónico en Galicia y Portugal. Las experiencias empresa muestran diversos enfoques de participación del sector privado en la mencionada implantación. Esta participación se concreta tanto en la definición del modelo de gestión documental como en proporcionar herramientas informáticas y de conservación de documentos a largo plazo. El libro incluye las conclusiones aprobadas en las 23 Jornadas de Archivos Universitarios.

Ponencias y experiencias empresa de las 23 Jornadas de Archivos Universitarios, 21-23 de junio de 2017, A Coruña. ISBN: 978-84-9749-680-3. DOI https://doi.org/10.17979/spudc.9788497496803 [Resumen] ARPAD (Archivo y Patrimonio Documental) es un proyecto desarrollado en el marco de la tercera convocatoria del Programa de Cooperación Transfronteriza España-Portugal (POCTEP) 2007-2013, que ha permitido crear el Archivo Digital Integrado de Galicia (o Archivo Electrónico de Galicia) y avanzar en la conservación y difusión del patrimonio documental en soporte tradicional custodiado en los archivos de la Comunidad Autónoma, entre otros objetivos. Impulsado por la Agencia para la Modernización Tecnológica de Galicia (AMTEGA), como beneficiario principal, ha contado con otros socios en la Xunta de Galicia (entre ellos la Secretaría Xeral de Cultura de la Consellería de Cultura, Educación y Ordenación Universitaria), el Ayuntamiento de Tui y la Diputación Provincial de Pontevedra, por parte española, y la Comunidade Intermunicipal do Minho-Lima (CIM Alto Minho), por la portuguesa. El Archivo Digital Integrado de Galicia se puede definir tanto como una estructura tecnológica como una estructura organizativa de procedimientos y responsabilidades. En cuanto a lo primero, permite la gestión y el archivo de documentos electrónicos producidos por el sector público autonómico y de copias digitalizadas de los documentos del patrimonio documental que se custodian en los archivos gallegos. En cuanto a lo segundo, permite el funcionamiento de esas infraestructuras y de cada uno de sus elementos de acuerdo con la legislación vigente y las normas y buenas prácticas internacionales. Son precisamente esas normas las que nos servirán de soporte didáctico en nuestra exposición.