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Selection on hybrids of ecologically divergent ecotypes of a marine snail: the relative importance of exogenous and endogenous barriers
No full textUnravelling the form of selection acting on hybrids of ecotypes undergoing ecological speciation is essential to understand the mechanisms behind the evolution of reproductive isolation in the face of gene flow. Shell phenotype is known to be affected by natural selection and is involved in the fitness of the marine snail Littorina saxatilis. Here, we studied the association between shell traits and fitness in hybrids in order to determine the relative role of exogenous and endogenous selection in this hybrid zone of L.saxatilis. We show that directional selection is the predominant mode of selection among hybrids. We also show its heterogeneity, affecting different shell traits, within populations at the level of the microhabitat. Therefore, endogenous selection mechanisms are most probably lacking in this hybrid zone and exogenous barriers (pre- and post-zygotic) are possibly one of the main forces behind the evolution of barriers to gene flow between these ecologically divergent ecotypes. This study shows how this barrier might represent an important type of reproductive isolation within ecological speciation, and this should be taken into account in future studies of speciation in hybrid zones.Ministerio de Ciencia e Innovación | Ref. CGL2008‐00135/BOSXunta de Galicia | Ref. 10PXIB 310044P
Videopodcast as an educational resource: application of ICT´s in blended learning
No full textLos materiales audiovisuales han obtenido una especial relevancia en el contexto educativo durante la pandemia mundial de COVID-19. Los videopodcast (VP) son creaciones audiovisuales seriadas vinculadas a un canal que les aporta una homogeneidad temática y formal. El presente proyecto de innovación educativa pretende crear canales de VP en el contexto de la educación superior como
herramienta del proceso enseñanza-aprendizaje. Para ello se reinterpretó el modelo metodológico CROA y se utilizaron equipamientos y recursos cercanos al profesorado para la elaboración propia de VP. Finalmente, se han podido desarrollar 3 canales de VP con un total de 14 creaciones audiovisuales vinculadas a diferentes materias de grado y postgrado, así como una herramienta sencilla para evaluar su
valor didáctico y técnico. Con un número de visualizaciones superior al millar, el estudiantado ha valorado positivamente la iniciativa mediante una evaluación anónima y voluntaria. Se concluye que el formato de VP proporciona elementos positivos al contexto de la educación superior mediante una estructura atractiva y motivadora para el estudiante.Audiovisual materials have gained particular relevance in the educational context during the global pandemic of COVID-19. Videopodcasts (VP) are serialised audiovisual creations linked to a channel that provides them with thematic and formal homogeneity. This educational innovation project aims to create VP channels in the context of higher education as a tool in the teaching-learning process. To this end, the
CROA methodological model was reinterpreted and equipment and resources close to the teaching staff were used for the creation of VP. Finally, it has been possible to develop 3 VP channels with a total of 14 audiovisual creations linked to different undergraduate and postgraduate subjects, as well as a simple tool to evaluate their didactic and technical quality. With more than a thousand views, the students have
positively evaluated the initiative by means of an anonymous and voluntary evaluation. It is concluded that the VP format provides positive elements to the context of higher education through an attractive and motivating structure for the student
New multi-GPU implementation for smoothed particle hydrodynamics on heterogeneous clusters
Get PDFA massively parallel SPH scheme using heterogeneous clusters of Central Processing Units (CPUs) and Graphics Processing Units (GPUs) has been developed. The new implementation originates from the single-GPU DualSPHysics code previously demonstrated to be powerful, stable and accurate. A combination of different parallel programming languages is combined to exploit not only one device (CPU or GPU) but also the combination of different machines. Communication among devices uses an improved Message Passing Interface (MPI) implementation which addresses some of the well-known drawbacks of MPI such as including a dynamic load balancing and overlapping data communications and computation tasks. The efficiency and scalability (strong and weak scaling) obtained with the new DualSPHysics code are analysed for different numbers of particles and different number of GPUs. Last, an application with more than 109 particles is presented to show the capability of the code to handle simulations that otherwise require large CPU clusters or supercomputers.Xunta de GaliciaMinisterio de Economía y Competitividad | Ref. BIA2012-38676-C03-03Research Councils UK (RCUK)University of ManchesterBarcelona Supercomputing CenterUniversidade de Vigo | Ref. INOU12-0
Tourist and seasonal lets in Galicia : An approach from the perspective of Decree 12/2017, of 26 January
Get PDFO Decreto 12/2017, do 26 de xaneiro, polo que se establece a ordenación de apartamentos turísticos, vivendas turísticas e vivendas de uso turístico na Comunidade Autónoma de Galicia, publicado no Diario Oficial de Galicia o 10 de febreiro de 2017, inclúe por primeira vez a regulación das vivendas de uso turístico na normativa sectorial turística galega. Paralelamente, os arrendamentos de tempada continúan ao abeiro da LAU como contratos que, sendo tamén de duración breve e con finalidade distinta da de residencia habitual do arrendatario, non participan da natureza turística do contrato de aloxamento.El Decreto 12/2017, de 26 de enero, por el que se establece la ordenación de apartamentos turísticos, viviendas turísticas y viviendas de uso turístico en la Comunidad Autónoma de Galicia, publicado en el Diario Oficial de Galicia el 10 de febrero de 2017, incluye por primera vez la regulación de las viviendas de uso turístico en la normativa sectorial turística gallega. Paralelamente, los arrendamientos de temporada continúan al amparo de la LAU como contratos que, siendo también de duración breve y con finalidad distinta de la de residencia habitual del arrendatario, no participan de la naturaleza turística del contrato de alojamiento.Published in the Official Journal of Galicia (Spain) on 10 February 2017 was Decree 12/2017, of 26 January, governing tourist apartments, tourist houses and homes for touristic use in the Autonomous Community of Galicia, thereby integrating regulation of tourist accommodation, for the first time, in the legislation governing the tourist sector. In parallel, seasonal lets as contracts that are non-touristic in purpose, being of short duration and with a purpose other than that of the habitual residence of the tenant, continue to be governed by the Law on Urban Lets
Exploring the limitations on RFID technology in traceability systems at beverage factories
Get PDFThe application of RFID in traceability of products in beverage factories is analyzed in terms of the electromagnetic conditions defined by the massive presence of metallic elements and liquids. Various experiments are reported to determine the maximum reading range from RFID tags installed on tanks or to read RFID information around bottles, both empty and full of wine, trying to put in context the possible problems that could appear when installing an RFID-based traceability system within a winery, a brewery, or any other beverage factory.European Commission (CIP-Pilot Actions) | Ref. 250444Xunta de Galicia | Ref. CN 2012/26
Performance analysis of input shaped model reference adaptive control for a single-link flexible manipulator
No full textMotion control for flexible link manipulators will have a great influence on their overall performance. Conventional control systems have the problem that they cannot compensate for the presence of uncertainty due to a variety of factors such as a change in the system itself-payload variations, degradation and modelling uncertainty. In addition, the underdamped structure of these systems entails motion-induced transient deflection and residual vibration. On the contrary, adaptive control, in particular Model Reference Adaptive Control (MRAC), has therefore been proposed to handle problems of this type dealing with other systems such as cranes, steering stability control for ground vehicles, airplanes and so on. This study presents a review and discussion on the MRAC and some individual issues of MRAC for these flexible link manipulators are addressed to specify: the state tracking error, the limitation of the adaptation values corresponding to the control gains and the control effort. Dealing with the last one, this work proves that shaping the command input to a Model Reference Adaptive Control (IS-MRAC) reduces the control effort necessary for the plant to follow the reference model and also mitigates the detrimental effects of flexibility. The IS-MRAC is implemented in a Single-Link Flexible Manipulator whose natural frequencies, experimentally and analytically estimated using the Transfer Matrix Method plus symbolic computation, vary significantly depending on payload mass and position. To this structured or parametric uncertainty, the proposed Lyapunov control law using the states associated with the low mode is designed for asymptotic stability and accommodates correctly. The state tracking, vibration suppression and control effort reduction performances of the proposed IS-MRAC combined controller are analysed via numerical simulations and experiments.Agencia Estatal de Investigación | Ref. PID2020-116984RB-C2
Automated transcatheter heart valve 4DCT-based deformation assessment throughout the cardiac cycle: Towards enhanced long-term durability
No full textBackground: Transcatheter heart valve (THV) durability is a critical concern, and its deformation may influence long-term performance. Current assessments rely on CT-based single-phase measurements and require a tedious analysis process, potentially overlooking deformation dynamics throughout the cardiac cycle. Methods: A fully automated artificial intelligence-based method was developed to assess THV deformation in post-transcatheter aortic valve implantation (TAVI) 4DCT scans. The approach involves segmenting the THV, extracting orthogonal cross-sections along its axis, fitting ellipses to these cross-sections, and computing eccentricity to analyze deformation over the cardiac cycle. Results: The method was evaluated in 21 TAVI patients with different self-expandable THV models, using one post-TAVI 4DCT series per patient. The THV inflow level exhibited the greatest eccentricity variations (0.35–0.69 among patients with the same THV model at end-diastole). Additionally, eccentricity varied throughout the cardiac cycle (0.23–0.57), highlighting the limitations of single-phase assessments in characterizing THV deformation. Conclusions: This method enables automated THV deformation assessment based on cross-sectional eccentricity. Significant differences were observed at the inflow level, and cyclic variations suggest that full cardiac cycle analysis provides a more comprehensive evaluation than single-phase measurements. This approach may aid in optimizing THV durability and function while preventing related complications
Texture collinearity foreground segmentation for night videos
No full textOne of the most difficult scenarios for unsupervised segmentation of moving objects is found in nighttime videos where the main challenges are the poor illumination conditions resulting in low-visibility of objects, very strong lights, surface-reflected light, a great variance of light intensity, sudden illumination changes, hard shadows, camouflaged objects, and noise. This paper proposes a novel method, coined COLBMOG (COLlinearity Boosted MOG), devised specifically for the foreground segmentation in nighttime videos, that shows the ability to overcome some of the limitations of state-of-the-art methods and still perform well in daytime scenarios. It is a texture-based classification method, using local texture modeling, complemented by a color-based classification method. The local texture at the pixel neighborhood is modeled as an -dimensional vector. For a given pixel, the classification is based on the collinearity between this feature in the input frame and the reference background frame. For this purpose, a multimodal temporal model of the collinearity between texture vectors of background pixels is maintained. COLBMOG was objectively evaluated using the ChangeDetection.net (CDnet) 2014, Night Videos category, benchmark. COLBMOG ranks first among all the unsupervised methods. A detailed analysis of the results revealed the superior performance of the proposed method compared to the best performing state-of-the-art methods in this category, particularly evident in the presence of the most complex situations where all the algorithms tend to fail.COMPETE 2020 | Ref. POCI-01-0247-FEDER-024498Fondo Europeo de Desarrollo RegionalXunta de GaliciaatlanTTic - research center for Telecommunication Technologie
Communicative mediation in the Spanish-Portuguese academic field. Second language teaching
Get PDFA partir de los presupuestos del Marco común europeo de referencia para las lenguas (MCERL, Consejo de Europa 2001) y del volumen complementario (Consejo de Europa 2020) sobre el papel de la mediación (y del mediador), se pretende, en este texto, analizar y reflexionar acerca de la mediación comunicativa como materia de enseñanza universitaria centrándonos en un caso específico, el de la mediación comunicativa en el ámbito académico hispanoportugués. Este campo suscita no pocos problemas de comunicación. Presentamos no un índice de frecuencias ni un glosario, sino una selección de términos representativos de los distintos tipos de actividades de mediación (de conceptos, de textos y de comunicación) y posibles errores achacables a la necesidad de mediación con los que se encuentran administrativos y estudiantes de uno y otro lado de la frontera.
Palabras clave: mediación comunicativa – español-portugués – ámbito académico.Based on the principles of the Common European Framework of Reference for Languages (Council of Europe 2001) and the companion volume (Council of Europe 2020) on the role of mediation (and the mediator), this text aims to analyze and reflect on communicative mediation as a subject in university teaching, focusing on a specific case: that of communicative mediation in the Spanish-Portuguese academic field. This field raises numerous communication problems. We present not a frequency index or a glossary, but rather a selection of representative terms for the different types of mediation activities (of concepts, texts, and communication) and possible errors attributable to the need for mediation that administrators and students encounter on both sides of the border.
Keywords: Communicative mediation – Spanish-Portuguese – academic field.Agencia Estatal de Investigación | Ref. PID2022-139084nb-c3
Grandes historias del arte. Grandes historias de amor
No full textObras da artista recollidas na exposición "Dende a fenda" Algunhas prácticas artísticas feministas en Galicia do 24 de novembro de 2022 ao 15 de xaneiro de 2023, Salas Rosalía de Castro e Maruja Mallo, Sede da Deputación en Vigo