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Item Fragile and orbital-obstructed topology in threefold-symmetric two-dimensional materials(2025) Arroyo Gascón, Olga; Bravo, Sergio; Chico Gómez, Leonor María; Pacheco, MónicaThe signatures of fragile and higher-order orbital-obstructed topological phases are systematically studied in a number of nonmagnetic two-dimensional materials belonging to space group P-3m1, most of them transition metal dichalcogenides.Item Strombolian fingerprint unveiled from multiresolution analysis of geophysical observations during the 2021 eruption at Cumbre Vieja, La Palma, Canary Islands.(2023) Arnoso Sampedro, José; Riccardi, U.; Blanco-Montenegro, I.; González Montesinos, Fuensanta; Benavent Merchán, María Teresa; Vélez, E. J.; Sánchez, N.; Sainz-Maza, S.; Del Barrio, C.We studied the deformation pattern across the Canary Islands derived from daily GNSS time series analysis spanning the period from 2017 to the present. From the GNSS velocity field, through a triangular segmentation approach, a 2D map of the infinitesimal deformation field across the archipelago was reconstructed. This study updates our previous one for the period 2011 to 2017, which revealed E-W and NE-SW orientation patterns influenced by the regional strain field, and also suggested that the extensional and compressional regimes in the region could influence the different episodes of volcanism in the Canary Islands. Our main interest was to characterize the deformation pattern in the youngest and westernmost islands of the archipelago where the most recent episodes of volcanism took place the 2011-2012 submarine eruption in El Hierro and the 2021 subaerial eruption in La Palma. In this study, special attention was paid to the area between the islands of Tenerife and Gran Canaria, an area of intense seismic activity, where several seismic swarms have been occurred since 2018.Item Género y diversidad sexual en políticas integrales de salud y salud sexual y reproductiva en el horizonte 2030: discusiones actuales y desafíos emergentes(2019) Blázquez Rodríguez, María IsabelLa incorporación de la perspectiva de género en la salud conlleva integrar la interacción entre el sexo, el género y otras variables sociales. A tal efecto se han planteado desde los años noventa diferentes enfoques: la salud de las mujeres, el género como determinante de la salud, la salud de los hombres y la salud LGTBIQ+. También con esta intención el movimiento feminista y el movimiento de las mujeres en la salud han propuesto incorporar algunos elementos como la crítica al androcentrismo en la ciencia y el conocimiento médico, el enfoque integral de las vidas de las mujeres, la crítica a la medicalización de sus vidas junto a su su empoderamiento y autonomía. Este artículo pretende analizar estos enfoques y elementos, que se conectan con algunos objetivos del Horizonte 2030 (objetivo 3, centrado en la salud y el objetivo 5, focalizado en la equidad en género). El caso de la República Dominicana y sus políticas en Salud y en Salud Sexual y Reproductiva servirán para mostrar las discusiones actuales y los desafíos emergentes en este campo.Item Deep and Shallow Srustal Structure of Gran Canaria Island (Canaries, Spain) through Gravity Inversion and Microseismic Sounding Modelling(2019) Gorbatikov, A.; Arnoso, José; Benavent Merchán, María Teresa; Stepanova, M; Blanco Montenegro, Isabel; Vélez, Emilio; Gómez Ortiz, David; Martín, TomásDifferent geophysical methods allow drawing crustal structures for a wide depth range and obtaininga more complete subsurface model of the study area. With this aim, a gravity inversion approach and microseismic sounding method (MSM) give more light to crustal structures in Gran Canaria Island. Ground and marine gravity data sets used in an inversion scheme (Montesinos et al., 2005) establish a 3D model distribution of density contrasts up to 15 km deep. MSM (Gorbatikov et al., 2011, 2013)unveils a distribution of low/high velocities up to 60 km deep through five observing profiles. Joint interpretation of MSM and gravity models reveals different volcanic scenarios of the island, their evolution from deeper sections, feeding systems and relations with tectonic or volcanic lineaments. 1) Low-density bodies found up to 3000 m in depth identify fractures acting as feeder dikes of monogenetic volcanoes during Post-Roque Nublo activity phase whilst a fragmented view appeared in the respective MSM model. 2) A shallower low-density body, placed between two high-density structures, identifies volcanic material related to the remains of a great stratocone (Roque Nublo group) around Tejeda collapse caldera. The MSM modelling distinguish a low velocity stock running from the surface up to more than 40 km deep. 3) Two deep high-density structures, from 18000 m depth to the surface and followed in the northwest sector through MSM, suggest the feeding system of the Miocene volcanic edifices whose remains presently outcrop as basalts. A contemporary magmatic fissure is suggested by seismic velocity change between10-20 km, to the southeast.Item Present-day 2D infinitesimal strain across the Canary Islands from GNSS data analysis(2023) Benavent Merchán, María Teresa; Riccardi, U.; Tammaro, U.; Arnoso Sampedro, José; González Montesinos, Fuensanta; Blanco- Montenegro, I.; Vélez, E.We studied the deformation pattern across the Canary Islands derived from daily GNSS time series analysis spanning the period from 2017 to the present. From the GNSS velocity field, through a triangular segmentation approach, a 2D map of the infinitesimal deformation field across the archipelago was reconstructed. This study updates our previous one for the period 2011 to 2017, which revealed E-W and NE-SW orientation patterns influenced by the regional strain field, and also suggested that the extensional and compressional regimes in the region could influence the different episodes of volcanism in the Canary Islands. Our main interest was to characterize the deformation pattern in the youngest and westernmost islands of the archipelago where the most recent episodes of volcanism took place the 2011-2012 submarine eruption in El Hierro and the 2021 subaerial eruption in La Palma. In this study, special attention was paid to the area between the islands of Tenerife and Gran Canaria, an area of intense seismic activity, where several seismic swarms have been occurred since 2018.Item The geomagnetic field at La Palma (Canary Islands) before, during and after the 2021 eruption at the Cumbre Vieja rift.(2023) Blanco-Montenegro, I.; Arnoso Sampedro, José; Sánchez, N.; González Montesinos, Fuensanta; Nicolosi, I.; Vélez, E.; Benavent Merchán, María TeresaAfter almost 50 years of quiescence, the Cumbre Vieja rift in La Palma underwent a reactivation process that culminated in a volcanic eruption from September 19 to December 13, 2021, preceded by a seismic swarm that started just eight days before the eruption onset. Seismic unrest started in October 2017 and comprised ten seismic swarms in five years, with the last one in August 2021. In July 2021, a magnetic station (CFU) was deployed in Cumbre Vieja, 2 km away from the site where the eruptive vents would open two months later. In September 2021, a second magnetic station (SAN) was installed near the southern end of the Cumbre Vieja rift. Both stations are still in operation today and acquire the total geomagnetic field intensity (F) with a sampling rate of 1 measurement/minute with two Overhauser magnetometers. In this work, we present the results of the analysis of these geomagnetic time series, which led to the identification of several signals of presumed volcanomagnetic origin. Our data revealed a magnetic signal at CFU station with an amplitude of 10 nT and a duration of 10 days by mid-August, one month before the eruption onset. During the eruption, the SAN magnetic station registered a magnetic signal with an amplitude of 17 nT in the second half of October. We analysed possible correlations with other physical parameters and concluded that these signals are the result of changes in the magnetization of rocks beneath the volcanic edifice related with volcanic activity.Item Gravity changes at Cumbre Vieja, La Palma (Canary Islands), associated with the 2021 eruption(2023) González Montesinos, Fuensanta; Arnoso Sampedro, José; Sainz-Maza Aparicio, Sergio; Gómez-Ortiz, D.; Blanco- Montenegro, I.; Benavent Merchán, María Teresa; Vélez, E.; Sánchez, N.; Martín-Crespo, T.The 2021 eruption at the Cumbre Vieja rift (La Palma, Canary Islands) lasted 85 days from September 19th to December 13th, becoming the longest historical eruption in this island. During this period, an elongated fissure eruption built a volcanic cone reaching 1,121 m a.s.l. Lava emerged from six major craters and up to nine minor vents with alternating activity, according to temporal variations in the eruptive process. We conducted several gravity surveys before, during and after this eruption that provided us with valuable spatial-temporal information to study this volcanic event. The obtained Bouguer anomaly map revealed a model of the shallow crustal structures before the eruption, which allowed to study the framework where the volcanic process developed. The analysis of the observed space-time gravity changes suggested a model of the magmatic feeding system, which draws the spatio-temporal path of magma ascent from the crust -mantle boundary to the surface. In addition, we also investigated the differences among the several gravity surveys to infer the possible mass changes that took place during the volcanic process. The interpretation of these gravity changes associated to the 2021 eruption at the Cumbre Vieja rift is supported by the analysis of the spatio-temporal distribution of the earthquake hypocenters preceding the eruption and the ground displacement calculated using GNSS data.Item Strain Pattern and Kinematics on Canary Islands from GNSS Time Series Analysis(2019) Arnoso, J.; Riccardi, I.; Benavent Merchán, María Teresa; Tammaro, U.; González Montesinos, Fuensanta; Blanco Montenegro, I.; Vélez, E. J.Following the 2004 seismic unrest at Tenerife and the 2012 eruption at El Hierro, the number of GNSS observing sites in the Canaries has remarkably increased making possible to obtain a more detailed picture of the displacement pattern and velocity maps useful to characterize the mechanism of the current deformation in that region. We review and interpret nearly 10 years of continuous GNSS data from MAGNET database to infer kinematics of the Canary sector of the Atlantic Ocean. In order to improve the velocities retrieved from the daily GNSS solutions we have computed the Common Mode bias from the whole data set and subtracted it from the time series of each site. Then, a lower standard error on the ITRF absolute velocities is achieved by reducing the scattering of the solutions around the linear trend. We thus image the strain patterns over the region using triplets of GNSS stations in triangular frames ranging the archipelago. From results, baselines between Tenerife and Gran Canaria undergo the largest elongations, about 10 , while in all the other directions these amount to 10 . Our interpretation turns out some evidences of the existence of a major crustal fracture in the central part of the archipelago, between Tenerife and Gran Canaria. This is in accordance with the observed clustering of the seismic activity and the recent magnetic studies as well, both supporting the idea that the genesis of Canary Islands might be conditioned by a strikeslip tectonic framework, probably related to Atlas tectonic features in Africa.Item CX3CL1 Delta Chemokine Is a Chronic Inflammatory Mediator That Links Periodontitis with Alzheimers Disease in Patients(2024) Merino Martín, José Joaquín; María Eugenia Cabaña-Muñoz; José María Parmigiani-Cabaña; Adolfo Toledano; José María Parmigiani-Izquierdo; Andrès, Emmanuel; Doi, KentTitanium is considered a biocompatible biomaterial of dental titanium alloys (Ti-6Al-4V). However, in patients with certain dental metals (Hg++, Al, Ti, etc.), including dental Ti implants, a chronic silent inflammatory state can be provoked. On the other hand, periodontitis favors the adherence of biofilms on the surface of teeth, increasing the local recruitment of innate immune cells (neutrophils, macrophages, anddendritic cells). Thus, a chronic proinflammatory cytokine release of cytokine/chemokines, including CX3CL1, can amplify the local inflammatory responses and also promote oral dysbiosis. In fact, recent studies link Alzheimer’s disease (AD) with periodontitis. However, systemic CX3CL1 andMCP-1 elevations can be also detected in patients with long-termdental Ti implants without periodontitis. Periodontitis favors tooth destruction and also enhances the accumulation of oral biofilm. In fact, porphyromonas gingivalis has been associated with AD, and high systemic CX3CL1 levels have been found to contribute to p-Tau accumulation in the brain of AD transgenic mice. Thus, this CX3CR1 overexpression as a chronic silent proinflammatory response can predispose patients with periodontal disease and poor buccal hygiene to AD. Collectively, CX3CR1 overproduction affects the normal control of the innate immune system and favors the destruction of the supporting tissues of the teeth in patients with periodontal disease. Thus, the link between AD and periodontitis via CX3CL1 opens up a new therapeutic role of delta chemokine blockers against periodontitis and AD pathology.Item Estudio fitoquímico y evaluación de la actividad citotóxica de P. porelloides(2025) Lobato-Garcia, Alejandro; Alarcon Cubelos, Mercedes; Bedoya Del Olmo, Luis Miguel; Bermejo Benito, Paulina; Cossío de Felipe, DavidEl melanoma es uno de los tipos de cáncer con peor pronóstico y presenta una alta resistencia a los tratamientos convencionales. En este estudio se evaluó el potencial citotóxico de los extractos de Plagiochila porelloides, una hepática rica en sesquiterpenos con posible actividad antitumoral. Se realizaron extracciones secuenciales y por infusión, seguidas de análisis fitoquímico mediante cromatografía en capa fina (TLC) y espectroscopía ¹H-RMN. La actividad citotóxica se evaluó in vitro frente a células de melanoma A375, y se llevaron a cabo estudios de docking molecular para predecir la interacción de los compuestos activos con la α-tubulina. Los extractos obtenidos con hexano y diclorometano mostraron la mayor actividad antiproliferativa, en correlación con una alta concentración de plagiochilinas sesquiterpénicas. El modelado molecular sugiere que estas moléculas podrían unirse al sitio de la pironetina en la α-tubulina, interfiriendo con el ciclo celular. Estos resultados indican que P. porelloides constituye una fuente prometedora de compuestos con potencial terapéutico frente al melanoma resistente.Item Implementation Relations for Distributed Testing(Applicable Formal Methods for Safe Industrial Products - Essays Dedicated to Jan Peleska on the Occasion of His 65th Birthday, 2023) Hierons, Robert M.; García Merayo, María De Las Mercedes; Núñez García, ManuelWhen testing a system that interacts with its environment at several physically distributed interfaces (ports) it is normal to place a local tester at each port. If the local testers do not synchronise their actions then the local tester at port p can only observe the sequence of inputs and outputs that occur at p. If, in addition, there is no global clock then it may be impossible to reconstruct the global trace that occurred in testing and testing is then using the distributed test architecture. As a result, the System Under Test (SUT) might be able to produce a global trace that is not allowed by the specification, and so would normally represent a failure, but where the local testers cannot observe this difference. The use of the distributed test architecture thus affects the ability of testing to distinguish between a specification and an SUT and so leads to the need for a different notion of correctness (implementation relation). This paper explores alternative implementation relations for distributed testing and how they relate.Item Testing the Robustness of Machine Learning Models Through Mutations(2024) Méndez Hurtado, Manuel; Benito Parejo, Miguel; García Merayo, María De Las MercedesThe reliable performance of machine learning algorithms stands as a critical and foundational concern. Usually, scientific attention centres solely on this aspect when selecting among models. However, in real-world scenarios, datasets are vulnerable to human errors during data input. Consequently, algorithms must display consistency and resilience against such errors. We assert that, especially in real-world applications, the resilience is, akin to the performance, a critical characteristic when selecting one algorithm over another. To address this concern, we propose a novel methodology for assessing model robustness by evaluating models both before and after applying mutations to the dataset. To validate the effectiveness of this methodology, we analyse five commonly used machine learning algorithms in a case study concerning traffic flow forecasting in Madrid. In assessing the robustness of the models, we introduce two metrics derived from well-known regression measurements. The results clearly reveal that the random forest model shows the highest robustness, according to our analysis, and that different models can exhibit very different behaviours in terms of this aspect.Item Characterization of the crustal structure of Timanfaya volcanic area (Lanzarote, Spain) through gravity study(2013) Benavent Merchán, María Teresa; Arnoso, josé; Vélez, E.J.; Benavent Merchán, María TeresaItem Study of sea level variability and vertical crustal motions at Gran Canaria (Canary Islands) from altimetry and tide gauge data(2013) Benavent Merchán, María Teresa; Arnoso, JoséItem Geodetic and Geophysic measurements in Lanzarote Island(2013) Vélez. Emilio; Arnoso, José; Soler, V.; Benavent Merchán, María Teresa; González Montesinos, FuensantaItem Bosch Imitators in Spain during the sixteenth and seventeenth centuries(2023) Vázquez Dueñas, Elena; Koldeweij, Jos; Cornelissen, WillekeItem Erosión mecánica (tillage erosion) vs. erosión hídrica(2005) Alba Alonso, Saturnino De; Van Oost, K.; Jiménez Ballesta, Raimundo; Álvarez González, Ana MaríaLa redistribución del suelo por arrastre mecánico durante las operaciones agrícolas de laboreo ha sido reconocido como un proceso per se de intensa degradación del suelo. En este trabajo se comparan los patrones espaciales de degradación del suelo producidos por erosión y redistribución mecánica del suelo y los producidos por erosión hídrica, así como las intensidades de sendos procesos a través de la revisión bibliográfica. Los resultados revelan la importancia de incorporar la redistribución mecánica del suelo, en modelos integrales de erosión e hidrológicos, así como de estudiar las posibles interacciones y sinergias entre los distintos procesos.Item Anelastic Response of the Earth’s Crust Underneath the Canary Islands Revealed from GPS Vertical Displacements and Gravity Ocean Tide Loading(2019) Arnoso Sampedro, José; Bos, M. S.; Benavent Merchán, María Teresa; Penna, N. T.; Sainz-Maza Aparicio, SergioWe report on the analysis of M2 kinematic GPS vertical displacement and tidal gravity measurements using 26 GPS and 3 gravimetric stations across the Canarian archipelago. In this region, recent ocean tide models have standard deviations of differences lower than 1.0 cm in amplitude and 2.9 degrees in phase, and are in close agreement with tide gauges (FES2014b shows an average difference of 1.9 cm and 1.9 degrees in amplitude and phase lag, respectively). These small ocean tide errors allow us to use the residual differences between observed and predicted ocean tide loading (OTL) values to study the elastic and anelastic properties of the solid Earth around the Canaries. First, in the prediction of OTL, we replaced the standard PREM earth model with STW105 and then S362ANI, which reduced the misfit between observations and predicted OTL values (from 1.1 to 0.6 mm for vertical displacements and 0.3 to 0.1 µGal for gravity with both models). Next, these models were adjusted for tidal periods by considering a constant quality factor Q at frequencies ranging from 1 s to 12.54 hours, which represent the absorption band of the asthenosphere. This yielded residual differences between observed GPS M2 vertical displacement and modelled values of less than 0.5 mm, except for the easternmost islands of Lanzarote and Fuerteventura, where they reach up to 2 mm at some stations. It is hypothesised that mantle upwelling underneath the Canary Islands, creating spatial variations in the elastic properties, causes the large residuals observed in the eastern islands.Item Efecto de la administración del flavonoide quercetina en la tasa de ovulación, consumo de alimento y composición corporal en conejas jóvenes y adultas(2023) Jordán Rodríguez, Daniela; Vicente Carrillo, Alejandro; Cáceres-Martín, Elisa; Gómez-León, Alicia; Rebollar, Pilar; Lorenzo González, Pedro Luis; García García, Rosa María; Arias Álvarez, María; García García, Rosa María; Arias Álvarez, MaríaLa utilización de antioxidantes como la quercetina (QUR) es de gran interés para mejorar la función reproductiva y la vida útil de las conejas. Para valorar los efectos de este flavonoide sobre dichos parámetros, se realizó un estudio con conejas jóvenes (grupo J) y adultas (grupo A) a las que se administró QUR (300 mg/ kg) (JQ y AQ) por vía oral durante 8 semanas y se compararon con conejas sin QUR (JC y AC). Se midió el peso corporal, el consumo de alimento, la composición corporal (% grasa, agua, cenizas, proteína y energía [kJ/100g]) y los parámetros reproductivos (peso medio del ovario, número de cuerpos lúteos [CL], tasa de ovulación, tasa de recuperación y niveles séricos de progesterona [P4]). Los resultados mostraron que la administración de QUR no influye en el crecimiento y mantenimiento del peso de las conejas jóvenes y adultas. La composición corporal se vio afectada por la edad (joven o adulta), con un porcentaje de proteína y agua mayor en las adultas y una tendencia a un mayor contenido graso en las JQ. El peso del ovario fue mayor en las conejas adultas. La tasa de ovulación fue del 100% en todos los animales y no hubo diferencias en el número de CL. Sin embargo, se observó una concentración de P4 mayor en las conejas adultas que en las JC, mostrando las conejas JQ niveles intermedios. En conclusión, la QUR administrada durante 8 semanas podría estar mejorando las reservas energéticas y la producción de P4 en las conejas jóvenes.