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A hybrid algorithm for iterative adaptation of feedforward controllers: An application on electromechanical switches
No full textElectromechanical switching devices such as relays, solenoid valves, and contactors offer several technical and economic advantages that make them widely used in industry. However, uncontrolled operations result in undesirable impact-related phenomena at the end of the stroke. As a solution, different soft-landing controls have been proposed. Among them, feedforward control with iterative techniques that adapt its parameters is a solution when real-time feedback is not available. However, these techniques typically require a large number of operations to converge or are computationally intensive, which limits a real implementation. In this paper, we present a new algorithm for the iterative adaptation that is able to eventually adapt the search coordinate system and to reduce the search dimensional size in order to accelerate convergence. Moreover, it automatically toggles between a derivative-free and a gradient-based method to balance exploration and exploitation. To demonstrate the high potential of the proposal, each novel part of the algorithm is compared with a state-of-the-art approach via simulation
Evaluación del riesgo y análisis de la respuesta hidrológica del Barranco de la Muerte (Zaragoza) ante inundaciones repentinas mediante simulación numérica
No full textSe presenta un análisis de la respuesta hidrológica del Barranco de la Muerte (Zaragoza) frente a eventos de precipitación intensa y corta duración, mediante simulación numérica con RiverFlow2D, basado en un método explícito de volúmenes finitos. El modelo considera un MDT y distribución espacial de usos del suelo de alta resolución, la infiltración del terreno y la incorporación de estructuras hidráulicas singulares. Se simulan dos episodios reales y lluvias sintéticas en función de la duración y el periodo de retorno del evento, obteniendo valores de calado y velocidad del flujo, que permiten caracterizar el comportamiento del barranco ante este tipo de situaciones. Se generan mapas web de evaluación del riesgo para personas y vehículos. Los resultados confirman la elevada vulnerabilidad de esta zona y la importancia de elaborar medidas de mitigación y planificación de riesgos.
A hydrological response analysis of the Barranco de la Muerte (Zaragoza) to short-duration, high-intensity rainfall events is presented.The study is conducted through numerical simulation using RiverFlow2D, based on an explicit finite volume method. The model incorporates a high-resolution Digital Terrain Model (DTM), detailed spatial distribution of land uses, soil infiltration processes, and the incorporation of specific hydraulic structures. Two real storm events and several synthetic rainfall scenarios are simulated. The outputs include water depth and flow velocity distributions, enabling a thorough characterisation of the ravine’s behaviour under extreme precipitation conditions. Web-based hazard maps for pedestrians and vehicles are generated. The results emphasise the area’s high vulnerability and the critical need for the development of mitigation measures and risk management planning
Los diarios para la identificación de estrategias de estrategias metacognitivas en educación plástica
No full textEste trabajo presenta los resultados de una investigación centrada en el análisis de la influencia que tienen la realización de diarios de reflexión en el desarrollo de estrategias metacognitivas. Se utilizó el estudio de caso como metodología de la investigación y diseño de tipo cualitativo. Se realizó un análisis de documentos, diarios reflexivos y observación participante como estrategia de recogida de información. A partir de los hallazgos obtenidos se concluye que el uso de los diarios tuvo un efecto positivo en el aumento de la conciencia metacognitiva de los estudiantes de educación artística. El diario de reflexión es una herramienta educativa que favorece en el alumnado estrategias de conocimiento hacia los procesos de aprendizaje artísticos.
This presentation shows the results of an investigation focused on the analysis of reflectionjournals for the development of metacognitive strategies in high school students. A case study was used as a research methodology and the analysis of documents, participant observation and diaries as a strategy for collecting information. From the findingsobtained, it is concluded that the use of newspapers had a positive effect on increasing the metacognitive awareness of the participants. In short, the journal us the occasion to promote knowledge strategies towards learning processes, important for a satisfactory acquisition of artistic processes
Characterization of Molecular Mechanisms of TXNDC5 and Its Role in Squalene Response Using Various Drug Delivery Systems in the AML12 Cell Line
No full textEnfermedad hepática esteatótica asociada a disfunción metabólica (MASLD), anteriormente conocida como enfermedad del hígado graso no alcohólico (NAFLD) es inducida por la acumulación de grasa en el hígado. El estrés del retículo endoplasmático (RE), el estrés oxidativo y la disfunción mitocondrial son elementos necesarios en el desarrollo de la MASLD. La proteína que contiene dominios tiorredoxina tipo 5 (TXNDC5) es un miembro de la familia de las tiorredoxinas y desempeña un papel fundamental como chaperona del RE involucrada en el mantenimiento de la homeostasis celular en condiciones de estrés. Sin embargo, los mecanismos moleculares precisos a través de los cuales TXNDC5 ejerce sus efectos sobre los hepatocitos en condiciones de estrés oxidativo y del RE siguen siendo incompletos. El objetivo de este estudio fue investigar los efectos de TXNDC5 sobre la acción del escuáleno, un antioxidante natural que se encuentra en el aceite de oliva virgen,administrado a través de varios sistemas de administración de fármacos para mejorar su biodisponibilidad. El escuáleno se encapsulo en nanoparticulas de PLGA y quitosano con el objetivo de mejorar su captación celular en células AML12 (hígado de ratón alfa) y célulasAML12 deficientes en TXNDC5 (KO) producidas mediante tecnología CRISPR/Cas9. La caracterización de las nanopartículas mediante microscopia electrónica, dispersión dinámica de la luz, análisis del potencial zeta y cromatografía liquida de alta resolución confirmo la encapsulación eficiente y la inclusión de escuáleno en diferentes concentraciones. La encapsulación de escuáleno en nanopartículas de quitosano demostró una absorción celular significativamente mejorada en comparación con los portadores de fármacos PLGA y etanol.Esto permite la administración de dosis mas altas, que mejoran la viabilidad de los hepatocitos y reducen los niveles de ROS, compensando eficazmente los efectos adversos de la deficiencia de TXNDC5 en el contexto de la protección contra el estrés de los hepatocitos.Los ensayos de viabilidad celular mostraron que TXNDC5 tiene un papel importante en la modulación de la viabilidad celular en condiciones de estrés oxidativo y de ER, como lo demuestra el hecho de que el escuáleno redujo eficazmente los ROS en las células AML12mientras aumentaba los ROS en las células deficientes en TXNDC5. Se observo que el escuáleno mejora la viabilidad celular en condiciones de estrés de ER al disminuir la expresión de marcadores de estrés de ER, incluidos ERN1 y EIF2AK3, e induciendo la expresión de proteínas protectoras como GPx4. Para determinar la función de TXNDC5 en las lineas celulares AML12 y KO, se utilizaron tunicamicina, acido palmitico y tapsigargina como factores de estres. Los resultados de la expresión de proteínas de los marcadores de estrés del RE mas destacados revelaron que, entre ellos, las proteínas ERN1 y EIF2AK3 estaban disminuidas y HSPA5 estaba aumentada. La tunicamicina ha alterado los niveles de proteínas de HSPA5, ERN1 y EIF2AK3 en las celulas KO. El acido palmitico modifico los niveles de proteínas de los sensores de estrés del RE, como ATF6, HSPA5 y EIF2AK3. TXNDC5 interaccionaba con PRDX6 y HSPA9, proteínas involucradas en la regulación redox de laperoxidación lipídica y el glutation, y con la pérdida de TXNDC5, estas vías tienen actividades reducidas, como se registro por la reducción de la peroxidación lipídica y del glutation. Por lo tanto, la pérdida de TXNDC5 afecto las funciones mitocondriales y altero específicamente losniveles de ARNm que codifican genes que participan en una respuesta al estrés oxidativo y en el proceso de plegamiento de proteínas.En conclusión, estos hallazgos muestran que TXNDC5 es un modulador de múltiples vías de señalizacion involucradas en el estrés oxidativo e inducido por ER en los hepatocitos, y que el escualeno, administrado a través de nanopartículas de PLGA y quitosano, previene la acción de estos estreses y apoya su accion protectora por las implicaciones terapeúticas subyacentes para la modulación de TXNDC5 con un sistema de administración de fármacos a dianas para proteger el hígado.-----------------Metabolic dysfunction¿associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD) is induced by fat accumulation within the liver. Endoplasmic reticulum (ER) stress, oxidative stress, and mitochondrial dysfunction are necessary elements in the development of MASLD. Thioredoxin domain-containing 5 (TXNDC5) is a member of the thioredoxin family and plays a pivotal role as an ER chaperone involved in maintaining cellular homeostasis in stress conditions. Nevertheless, the precise molecular mechanisms through which TXNDC5 exerts its effects on hepatocytes under conditions of oxidative and ER stress remain incompletely understood. The objective of this study was to investigate the effects of TXNDC5 on squalene action, a natural antioxidant found in virgin olive oil, delivered through various drug delivery systems to enhance its bioavailability. Squalene was encapsulated in PLGA and chitosan nanoparticles with the aim of enhancing its cellular uptake in AML12 (alpha mouse liver) cells and TXNDC5-deficient AML12 cells (KO) produced by CRISPR/Cas9 technology. Characterization of the nanoparticles by electron microscopy, dynamic light scattering, zeta potential analysis, and high-performance liquid chromatography confirmed efficient encapsulation and inclusion of squalene at different concentrations. The encapsulation of squalene in chitosan nanoparticles demonstrated a significantly enhanced cellular uptake in comparison to the PLGA and ethanol drug carriers. This enables the administration of higher doses, which enhance hepatocyte viability and reduce ROS levels, effectively compensating for the adverse effects of TXNDC5 deficiency in the context of hepatocyte stress protection.Cell viability assays showed that TXNDC5 has an important role in modulating cell viability under conditions of oxidative and ER stress, as evidenced by the fact that squalene effectively reduced ROS in AML12 cells while increasing ROS in TXNDC5-deficient cells. Squalene was observed to enhance cell viability under conditions of ER stress by decreasing the expression of ER stress markers, including ERN1 and EIF2AK3, and by inducing the expression of protective proteins such as GPx4. To ascertain the function of TXNDC5 in AML12 and KO cell lines, tunicamycin, palmitic acid, and thapsigargin were utilized as stressors. The results from protein expression of the most prominent ER stress markers revealed that among them, the proteins ERN1 and EIF2AK3 were downregulated and HSPA5 was upregulated. Tunicamycin has disrupted the protein levels of HSPA5, ERN1, and EIF2AK3 in KO cells. Palmitic acid modified the protein levels of the ER stress sensors, such as ATF6, HSPA5, and EIF2AK3. TXNDC5 interacted with PRDX6 and HSPA9, proteins involved in the redox regulation of lipid peroxidation and glutathione, and with the loss of TXNDC5, these pathways do have reduced activities, as was recorded by reduced lipid and glutathione peroxidation. Thereby, loss of TXNDC5 impacted mitochondrial functions and specifically disrupted the mRNA levels coding genes that participate in an oxidative stress response and protein folding process.In conclusion, these findings show that TXNDC5 is a modulator of multiple signaling pathways involved in oxidative and ER-induced stresses in hepatocytes, which squalene, given through PLGA and chitosan nanoparticles, prevents the action of these stresses and supports its protective action by the underlying therapeutic implications for modulation of TXNDC5 with a drug-target delivery system to protect the liver.<br /
Incorporating the vertical velocity in a coupled Lagrangian–Eulerian approach for particle transport in shallow flows
No full textThis work presents a method to incorporate vertical velocity into a two-dimensional depth-averaged Shallow Water Equation (2DH SWE) model, thereby improving the calculation of particle trajectories in a Lagrangian Particle Tracking (LPT) framework. The resulting formulation couples Eulerian and Lagrangian approaches. The vertical velocity is also used to modify the dispersion terms in the LPT model. The proposed approximation is first validated—without particle transport—by comparison with Hyperbolic–Elliptic and Hyperbolic-Relaxed Non-Hydrostatic Pressure (NHP) models. The differences between models are minor, confirming the suitability of the vertical velocity approximation for shallow flow problems. Subsequently, the method is applied to particle transport scenarios, demonstrating that including vertical velocity yields more realistic particle trajectories in complex flow situations
Factors associated with prescription of modern antidiabetics in newly diagnosed patients with type 2 diabetes. a real-world data study in a Spanish region
No full textAimTo describe the patterns of first prescription of antidiabetic drugs (AD) in patients with type 2 diabetes (T2D) and analyze the factors associated with the prescription of a modern one.MethodsObservational longitudinal study conducted in the CArdiovascular Risk factors for HEalth Services research (CARhES) cohort. Individuals older than 15, resident in Aragón (Spain), diagnosed with T2D during 2018–2022 were selected and followed-up until 31st December 2022. Secondary use of data from the health system provided sociodemographic, clinical and pharmacological prescription information. We also considered additional variables by Basic Healthcare Area (BHA) of residence. AD were classified into “classical” and “modern” and their differences were described and compared. A multilevel methodology stratified by sex was developed, considering individual characteristics and characteristics of the BHA of residence, to analyze the factors associated to a modern AD.ResultsOur population-based cohort of 22,892 patients were mostly male, native, low-income and living in non-depopulated BHA. People who were younger, with heart failure, ischemic heart disease, chronic renal failure, obesity, with a previous major adverse cardiovascular event, higher socioeconomic level or lived in less deprived and more depopulated areas were more likely to get a modern AD prescription.ConclusionOur analyses showed that prescribing practices vary according to a range of sociodemographic, clinical and geographical characteristics. Knowledge of these factors is essential for implementing and improving equitable and person-centered approaches
Cross-Cultural Differences in Gastrointestinal Symptoms and Sensory Responses in Individuals with Autism: A Comparison Between Spain and Colombia
No full textBackground: Between 40 and 70% of the population with autism have been found to suffer from functional gastrointestinal disorders (FGIDs). The emergence of FGIDs is related to lower quality of life and greater medical resources, somatization and emotional instability. There is a paucity of research available that examines gastrointestinal symptoms and sensory responses in individuals with autism in different countries and cultures. The aim of the present study is to compare the possible differences between gastrointestinal symptoms and sensory reactivity between two samples of individuals with autism from Spain and Colombia. Methods. Differences in gastrointestinal symptoms and sensory response were analysed between individuals with autism from Spain (n = 65; mean age = 8.91, SD = 4.02) and Colombia (n = 62; mean age = 10.16, SD = 5.31). Results. No differences were found as a function of age, sex and autism severity between Spanish and Colombian participants. More severe functional nausea and vomiting was reported by the Colombian sample when compared with the Spanish sample (p < 0.00, d = 0.42). Similarly, greater sensory reactivity emerged in Colombian individuals with autism relative to Spanish individuals with autism. Conclusions. Due to methodological limitations, sample size and other factors that could not be analysed in this research, it is not possible to draw conclusions about the influences of cultural or biological factors on gastrointestinal symptomatology and sensory reactivity among both autistic populations. This work could encourage more rigorous cross-cultural research in the future
Low back pain after total hip arthroplasty: Long-term retrospective cohort study
No full textIntroduction and objective: Total hip arthroplasty (THA) effectively treats hip osteoarthritis, but postoperative low back pain (LBP) is a known complication. While prior studies report short-term LBP resolution, long-term outcomes and incidence in patients without prior LBP remain unclear. This study aims to determine the long-term cumulative prevalence of LBP post-THA. Material and methods: A longitudinal retrospective cohort study was conducted on 476 patients undergoing THA for coxarthrosis at Lozano Blesa University Clinical Hospital of Zaragoza (2010–2020). Pre- and postoperative LBP (lumbar pain ≥7 days) and sociodemographic, clinical, and postsurgical variables were analyzed. Strict exclusion criteria were applied. The study was approved by the CEICA (C.P.-C.I.-PI21/346) and registered at ClinicalTrials.gov (NCT05647629). Results: Among 476 patients (mean age: 60.11 ± 8 years; mean follow-up: 7 years), four clinical trajectories were identified: 202 (42.43%) without pre/postoperative LBP, 97 (20.37%) without preoperative but with postoperative LBP (P = 0.002), 128 (26.89%) with pre- and postoperative LBP (P < 0.001), and 49 (10.29%) with preoperative but without postoperative LBP. Overall, 47.26% (n = 225) experienced postoperative LBP. Weak correlations were observed between BMI (R = 0.16; P = 0.040) and weight (R = 0.22; P = 0.004) with LBP in patients with preoperative LBP, with no differences in age or sex. Conclusions: Post-THA LBP affects 47.26% of patients long-term (26.89% persistent, 20.38% new onset). BMI and weight are modest associated factors. The heterogeneity of surgical impact highlights the need for prospective studies to optimize management. Resumen: Introducción y objetivo: La artroplastia total de cadera (ATC) es un tratamiento eficaz para la coxartrosis, pero el dolor lumbar postoperatorio (LBP) es una complicación conocida. Aunque estudios previos reportan resolución a corto plazo, la evolución a largo plazo y su proporción en los pacientes sin antecedentes son menos claras. Este estudio determina la proporción de LBP a largo plazo tras ATC. Material y métodos: Se realizó un estudio de cohorte retrospectivo longitudinal con 476 pacientes sometidos a ATC por coxartrosis en el Hospital Clínico Universitario Lozano Blesa de Zaragoza (2010-2020). Se analizó la presencia de LBP (dolor lumbar ≥ 7 días) pre y postoperatorio, junto con variables sociodemográficas, clínicas y eventos posquirúrgicos. Se aplicaron criterios de exclusión estrictos. Aprobado por el CEICA (C.P.-C.I.-PI21/346) y registrado en ClinicalTrials.gov (NCT05647629). Resultados: En 476 pacientes (60,11 ± 8 años; seguimiento: 7 años), se identificaron cuatro trayectorias: 202 (42,43%) sin LBP pre/postoperatoria, 97 (20,37%) sin LBP preoperatoria, pero con LBP postoperatoria (p = 0,002), 128 (26,89%) con LBP pre y postoperatoria (p < 0,001), y 49 (10,29%) con LBP preoperatoria, pero sin postoperatoria. El 47,28% (n = 225) presentó LBP postoperatoria. Se observaron correlaciones débiles entre IMC (R = 0,16; p = 0,040) y peso (R = 0,22; p = 0,004) con LBP en pacientes con LBP preoperatoria, sin diferencias en edad o sexo. Conclusiones: El 47,28% de pacientes presenta LBP post-ATC a largo plazo (26,89% persistente, 20,38% de nuevo inicio). El IMC y el peso son factores asociados modestos. La heterogeneidad del impacto quirúrgico resalta la necesidad de estudios prospectivos para optimizar el manejo
Photon absorption in a doubly special relativity model with undeformed free propagation and total momentum conservation
No full textThe lack of a dynamical framework within doubly special relativity theories has impeded the development of a corresponding phenomenology of modified interactions. In this work we show that in a model based on the classical basis of κ-Poincaré and total momentum conservation, one has a well-defined cross section of the photon-photon annihilation process, once a prescription for the channel treatment is set. The modification of the interaction can lead to observable effects in the opacity of the Universe to very high-energy gamma rays when the gamma-ray energy approaches the energy scale of the deformation. The magnitude and observability of this deformation are examined as functions of the gamma-ray energy and source distance