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Zuntz optikozko sentsore aurreratuak desplazamendu lineal eta angeluarrerako
No full text283 p.Industry 5.0 calls for photonic solutions that gather precise, real-time measurements under intense heat, vibration, and electromagnetic fields. Conventional electronics struggle here, often succumbing to interference or limited durability. This dissertation overcomes that gap by developing intensity-based optical fiber displacement sensors (OFDS) that measure linear and angular displacements with high accuracy, extended range, and minimal dead zones.This research closes the loop on OFDS design by uniting theoretical modeling, simulation, and hands-on fabrication. First, a brute-force methodology mapped a broad range of geometries, revealing surprising flexibility even under tight manufacturing tolerances. Next, a concise toy model distilled complex photonic interactions into three key equations¿greatly reducing computational overhead while preserving sub-1\% agreement with experiments. Building on these insights, we engineered tetra- and pentafurcated OFDS prototypes with extended linear ranges up to 10.49 mm minimal dead zones (2.50 mm) and high sensitivity 2.20 mm-1, validated experimentally at a mean square error of 0.25%.Finally, we introduced a heptafurcated optical fiber displacement angular and linear sensor (OFLADS), integrating concentric fiber rings for linear sensing with cross-arranged fibers for angular detection. This single, compact bundle simultaneously measures distance and tilt angles (±15º) without bulky optics or intricate alignment. Prototypes confirmed theoretical predictions, underscoring the viability of the sensor for demanding aero-engine applications.By merging rigorous modeling, efficient design strategies, and empirical testing, this dissertation surpasses state-of-the-art OFDS limitations and completes the circle from conceptual frameworks to fully operational, multi-parameter photonic sensors. The path ahead includes further miniaturization, broader angular detection, and integration with cutting-edge photonic platforms solidifying OFDS as a key enabler of next-generation aerospace and industrial systems
Análisis económio-financiero del sector vitivinícola: comparación entre las Denominaciones de Origen Rioja Y Ribera de Duero
No full textEl presente Trabajo de Fin de Grado tiene como objetivo principal analizar y comparar la situación económico-financiera de dos de las principales Denominaciones de Origen del sector vitivinícola español: Rioja y Ribera del Duero, con el fin de identificar semejanzas y diferencias en términos de estructura de inversión, financiación, rentabilidad, solvencia y liquidez. En primer lugar, se realiza un breve análisis del sector vitivinícola en España y se define el concepto de Denominación de Origen, incluyendo una síntesis de la trayectoria histórica de ambas denominaciones analizadas. Posteriormente, se lleva a cabo un estudio económico-financiero detallado mediante un análisis del Balance de Situación y de la Cuenta de Pérdidas y Ganancia, Estado de Flujos de Efectivo y ratios financieros
Lantanido(III) ioietan eta 2-oxonikotinato estekatzailean oinarritutako koordinazio-polimero eta gel lumineszenteak
No full text[EU] Lan honen helburu nagusia azido 2-hidroxinikotinikotik (H2hnic) eratorritako ligandoaz eta lantanido ioi desberdinez osatutako koordinazio-konposatu berrien sintesia eta karakterizazioa da.
Sintesian zehar, H2hnic molekulak desprotonatu eta prototropia jasaten dute non alkohol taldeko hidrogeno atomoa eraztun aromatikoko nitrogenora mugitzen den, 1H-2-oxonikotinato (2onic) tautomeroa lortuz, zein ioi lantanido(III)-ekin erraz koordinatzen den. Koordinazio-konposatuak sintetizatu ondoren, bere funtsezko karakterizazio fisiko-kimikoa egin da teknika esperimental desberdinak erabiliz: analisi elementala (AE), infragorri espektroskopia (FT-IR), X-izpi bidezko difrakzioa lagin polikristalinoan (PXRD) eta analisi termikoa (TGA). Monokristala lortu egin deneko kasuetan, haren kristal egitura ebatzi da X-izpien bidezko difrakzioaren (SCXRD) bitartez. Horrela, konposatuen purutasuna eta kristalinitatea aztertu da.
Lan honetan egitura kristalino ezberdinen hiru familia aurkezten dira. Batetik, {[M2(μ3-2onic)4(H2O)4](ClO4)2·2H2O}n (1-M) formularekin bat datozen zortzi koordinazio-polimero isoestruktural lortu dira eta hauen azterketa fotofisiko sakona egin da. Konposatu hauen egiturak malgutasun handia erakutsi du tenperatura eta presio aldakorraren aurrean, egituraren deshidratazio partzialaren eta kristalizazio ur-molekulen eta perklorato anioien berrantolaketaren ondorioz. Konposatu gehienek propietate fotolumineszente (PL) onak erakusten dituzte egoera solidoan eta baita ur-disoluzioan ere, metodo semi-enpiriko eta DFT (Density Functional Theory) kalkulu konputazionalen bidez lortutako emaitzen bidez baieztatu egin dena. Egoera solidoan gertatzen diren aldaketa fisikoek eragindako egitura-dinamikak aprobetxatuz, tenperatura eta presio hutsunearen aurrean aztertuak izan dira konposatuak. 1-Eu konposatuan, hutsunepean, ligandoak lantanido-ioiari energia transferitzeko duen ahalmena handitzen da giro-baldintzekin konparatuz eta, bestalde, 1-Tb-ren kasuan, deshidratazio termikoak konposatuaren QY-a nabarmen handitzen du (giro-baldintzetako %1.6tik %13.4ra konposatu anhidroan). Bestalde, konposatu hauek uretan disolbagarriak izateari esker, haien PL propietateak uretan ere aztertu dira. Aipatzekoa da, 1-Tb konposatuaren kasuan, disoluzioan lortutako QY-a egoera solidoan lortutakoa baino altuagoa dela (%1.6tik %21.5ra handituz). Azkenik, 1-Nd eta 1-Yb konposatuek infragorri hurbilean (NIR) emititzen dute, eta aipatzekoa da Nd-zko konposatuak giro-tenperaturan ere bere emisio bereizgarria erakusten duela.
Bestetik, ezaugarri fluoreszente onak aurkezten dituzten beste bi konposatu heterobimetaliko isoestruktural lortu dira, {[Ln₃Na₃(2onic)₁₂(H₂O)₆]·4H₂O}n (2-M) formularekin karakterizatuak, zeintzuk, ioi lantanidoez gain, sintesian base modura erabilitako sodio hidroxidoaren sodio ioiak ere kristalizatzen dutelarik. Aipagarria da hasierako erreaktibo-nahasketaren baldintza kimikoak zertxobait aldatuz, zehazki medioa basikotuz, gel egorako material metal-organikoz osatutako hirugarren familia (3-M) bat ere lortu egin dela, propietate porotsu eta lumineszente interesgarriak izateaz gain 2-M konposatuen monokristalak sortzeko aproposak izan direnak. 2-M konposatuen kasuan, egitura kristalinoaren deskribapen zehatza egin da eta laginaren propietate lumineszenteak giro-tenperaturan aztertuak izan dira. Era berean, 3-M gelaren karakterizazio prozesuari hasiera eman zaio, xerogel moduan aztertuz. Xerogelaren portaera termikoa eta beste hainbat karakterizazio-teknika (SEM-EDS, XPS, XRF eta neurketa erreologikoak) desberdinak erabiliz konposatu horren konposizioa argitu egin da.[EN] The main objective of this work is the synthesis and characterization of new coordination compounds derived from the ligand 2-hydroxynicotinic acid (H2hnic) and different lanthanide ions.
During the synthesis, H2hnic molecules suffer deprotonation and prototropy, in which the hydrogen atom of the alcohol group migrates to the nitrogen of the aromatic ring, leading to the formation of the tautomer 1H-2-oxonicotinate (2onic), which easily coordinates with lanthanide(III) ions. After synthesizing the coordination compounds, their essential physicochemical characterization was carried out using various experimental techniques: elemental analysis (EA), infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), and thermal analysis (TGA). In cases where single crystals were obtained, their crystal structure was solved using single-crystal X-ray diffraction (SCXRD). In this way, the purity and crystallinity of the compounds were assessed.
In this work, three families of compounds with different crystalline structures are presented. Firstly, eight isostructural coordination polymers were obtained with the formula {[M2(μ3-2onic)4(H2O)4](ClO4)2·2H2O}n (1-M), and an in-depth photophysical analysis of them was conducted. These compounds' structures present significant flexibility in response to changes in temperature and pressure, due to partial dehydration of the structure and rearrangement of the crystallization water molecules and perchlorate anions. Most of these compounds exhibit good photoluminescent (PL) properties both in the solid state and in aqueous solution, as confirmed by results obtained through semi-empirical and DFT (Density Functional Theory) computational calculations. Taking advantage of the structural dynamics caused by physical changes occurring in the solid state, the compounds were studied under variable temperature and vacuum pressure. In the 1-Eu compound, under vacuum, the ligand’s ability to transfer energy to the lanthanide ion increases compared to ambient conditions. In the case of 1-Tb, thermal dehydration significantly increases the compound’s QY (from 1.6% under ambient conditions to 13.4% in the anhydrous compound). Furthermore, due to the compounds' water solubility, their PL properties in aqueous solution were also studied. It is worth mentioning that, for the 1-Tb compound, the QY obtained in solution is even higher than that in the solid state (from 1.6% to 21.5%). Lastly, the 1-Nd and 1-Yb compounds emit in the near-infrared (NIR) region, with the Nd-based compound notably displaying its characteristic emission even at room temperature.
On the other hand, two additional isostructural heterobimetallic compounds were obtained which, besides exhibiting good fluorescent properties, are characterized with the formula {[Ln₃Na₃(2onic)₁₂(H₂O)₆]·4H₂O}ₙ (2-M). These compounds incorporate sodium ions from the sodium hydroxide used as a base in the synthesis, in addition to the lanthanide ions. It is worth mentioning that, by slightly modifying the chemical conditions of the initial reagent mixture, specifically by making the medium more basic, a third family (3-M) in the form of gels was also obtained. These gels are not only interesting for their porosity and luminescent features but have also proven to be suitable for obtaining single-crystals of the 2-M compounds. In the case of the 2-M compounds, a detailed description of their crystalline structure was achieved, and their luminescent properties were studied at room temperature. Likewise, the characterization process of the 3-M gels has been initiated, analyzed in xerogel form. The thermal behavior of the xerogel, along with several other characterization techniques (SEM-EDS, XPS, XRF, and rheological measurements) was examined, elucidating the composition of this compound
New data on text reading in English as a second language
No full textPublished online 12th March, 2025.This paper reports an expansion of the English as a second language (L2) component of the Multilingual Eye Movement Corpus (MECO L2), an international database of eye movements during text reading. While the previous Wave 1 of the MECO project (Kuperman et al., 2023) contained English as a L2 reading data from readers with 12 different first language (L1) backgrounds, the newly collected dataset adds eye-tracking data on English text reading from 13 distinct L1 backgrounds (N = 660) as well as participants’ scores on component skills of English proficiency and information about their demographics and language background and use. The paper reports reliability estimates, descriptive statistics, and correlational analyses as means to validate the expansion dataset. Consistent with prior literature and the MECO Wave 1, trends in the MECO Wave 2 data include a weak correlation between reading comprehension and oculomotor measures of reading fluency and a greater L1-L2 contrast in reading fluency than reading comprehension. Jointly with Wave 1, the MECO project includes English reading data from more than 1,200 readers representing a diversity of native writing systems (logographic, abjad, abugida, and alphabetic) and 19 distinct L1 backgrounds. We provide multiple pointers to new venues of how L2 reading researchers can mine this rich publicly available dataset.Research reported in this publication was supported by the following grants and organizations: Social Sciences and Humanities Research Council of Canada Partnered Research Training Grant, 895-2016-1008 (primary investigator [PI]: G. Libben); Social Sciences and Humanities Research Council of Canada Insight Grant, 435-2021-0657; Canada Research Chair (Tier 2; PI: V. Kuperman); German Federal Ministry of Education and Research, 01| S20043 (PI: L. A. Jäger); National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico) of Brazil Project 316036/2021-8 (PI: R. Rothe-Neves); Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico; Obel Family Foundation Research Equipment Grant to Aalborg University, 2017 (PI: H. B. S. Knudsen); UK Research and Innovation Economic and Social Research Council South Coast Doctoral Training Partnership, ES/P000673/1; Project Fondecyt Regular by the National Research and Development Agency (ANID-CHILE), 1201440 (PI: R. Ibáñez Orellana); Project Fondecyt de Postdoctorado by the National Research and Development Agency (ANID-CHILE), 3210252 (PI: A. Santana Covarrubias); Chinese Language and Technology Center, National Taiwan Normal University, within the Higher Education Sprout Project framework by the Ministry of Education in Taiwan (PI: Y. T. Sung); Basic Research Program at the National Research University Higher School of Economics (HSE University); Ministry of Science, Technological Development and Innovation of the Republic of Serbia; Israel Science Foundation Grant, project 1034/23 (PI: N. Siegelman), and Azrieli Early Career Faculty Fellowship (PI: N. Siegelman)
Lehen Hezkuntzatik Derrigorrezko Bigarren Hezkuntzarako transizioaren erronkak eta aukerak. Berrikuspen sistematikoa
No full text[EUS] Gradu Amaierako Lan honek LHtik DBHrako trantsizioaren inguruko ikuspegi teorikoak eta ikasleen esperientziekin duten lotura aztertzen ditu. Helburua trantsizio horrek ikasleen ongizate emozionalean, harreman sozialetan, esku-hartze hezitzaileetan eta hezkuntza-desberdintasunetan duen eragina aztertzea da, trantsizio-prozesuak hobetzeko proposamenak egiteko. Horretarako, PRISMA jarraibideei jarraituz, berrikuspen sistematikoa egin da, eta 14 artikulu zientifiko hautatu eta aztertu dira. Emaitzek adierazi dute trantsizioak erronka esanguratsuak dakartzala, eta horrek esku-hartze integrala eta pertsonalizatua eskatzen du, ikasleen behar emozionalak eta sozialak ardatz hartuta.[ES] Este Trabajo de Fin de Grado analiza las perspectivas teóricas sobre la transición de la Educación Primaria a la Educación Secundaria Obligatoria y su relación con las experiencias del alumnado. El objetivo es examinar el impacto de dicha transición en el bienestar emocional, las relaciones sociales, las intervenciones educativas y las desigualdades escolares, con el fin de proponer mejoras en los procesos de transición. Para ello, se ha llevado a cabo una revisión sistemática siguiendo las directrices PRISMA, en la que se han seleccionado y analizado 14 artículos científicos. Los resultados indican que la transición conlleva desafíos significativos, lo que requiere una intervención integral y personalizada centrada en las necesidades emocionales y sociales del alumnado.[EN] This Bachelor’s Thesis explores theoretical perspectives on the transition from Primary Education to Lower Secondary Education and examines their connection to students' lived experiences. The main objective is to analyse the impact of this transition on students' emotional well-being, social relationships, educational interventions, and educational inequalities, with the aim of proposing improvements to transition processes. To achieve this, a systematic review was conducted following the PRISMA guidelines, through which 14 scientific articles were selected and analysed. The results indicate that the transition entails significant challenges, requiring a comprehensive and personalized intervention focused on students’ emotional and social needs
Machinery detection by impulsive noise recognition using WiFi sensing
No full textEngines and electrical devices in operation generate electromagnetic pulses, also called impulsive noise (IN), that interfere with wireless signals. The IN shall affect the channel estimation process and is, therefore, present in the channel state information (CSI) provided by wireless receivers. In this paper, impulsive noise (IN) is used as a fingerprint of electrical devices to identify the IN sources that interfere with a WiFi signal, taking into account that each individual machine has a unique pattern of impulsive noise. In this sense, the WiFi CSI provides valuable information to recognize the IN sources through deep learning (DL) strategies. Two DL models have been proposed and tested on two experimental data sets for multiclass and multilabel analysis; in multiclass, devices can operate alone during the measurement, and in multilabel, multiple devices can work simultaneously in a more realistic scenario. The model transferability between location and days has also been evaluated by analyzing two different IN feature sets for device classification with the Few-shot-learning (FSL) model. Results show that the proposed DL models can recognize multiple devices working simultaneously through the IN and also offer an acceptable transferability performance ( 80% accuracy for a five-class problem).This work has been financially supported by the Basque Government, Spain (under grant IT1436-22), and by the Spanish Government (under project THERESA, grant PID2021-124706OB-I00, funded by MICIU/AEI/ 10.13039/ 501100011033 and by ERDF A way of making Europe )
Civilizar a las víctimas, hacer ciudadanos. Identidades en espejo y un deseo inconfesable
No full textAs an archetypal subject of our current societies, the victim has emerged as a mirror image of the citizen.The relevance of victims in the contemporary world generates controversy. Some are suspicious of the ubiquity of the "victimhood paradigm" and the concomitant "punitive turn", while others praise them as agents of ‘resistance’ and "memory", emphasizing their politicization. These views, which denounce and prescribe, highlight the emotional character of the victim identity and the transformation of suffering into political action. There is a meeting point between them that is based on an unspeakable desire: the aspiration for victims to become citizens, as part of a particular evolutionary succession. The path towards politics would leave emotions behind and bring them closer to civilizational rationality; politicization would go beyond the path of feelings as a mode of public expression. Drawing on empirical research, I propose here that far from being an emotional fuel, the forms that suffering assumes are, from the victims’ point of view, conflictive; I also explore the way in which they represent the politicization of their demands, no longer as an inevitable and desirable issue but, instead, as a contaminating danger to be avoided.; Como sujeto arquetípico de nuestras sociedades actuales, la víctima ha surgido en tanto reflejo espejado del ciudadano. Su protagonismo en el mundo contemporáneo genera controversias. Unos miran con desconfianza la ubicuidad del "paradigma victimista" y el "giro punitivo" concomitante, otros enaltecen a las víctimas como agentes de "resistencia" y "memoria" destacando su politización. Estas miradas, que denuncian y prescriben, resaltan el carácter emocional de la identidad de víctima y la transformación del sufrimiento en acción política. Entre ellas hay un punto de encuentro que se apoya sobre un deseo inconfesable: la aspiración de que las víctimas se transformen en ciudadanos, como parte de una particular sucesión evolutiva. El camino hacia la política dejaría atrás a las emociones para acercarlas a la racionalidad civilizatoria; la politización superaría la vía de los sentimientos como modo de expresión pública. Basándome en diversas investigaciones empíricas, propongo que lejos de ser un simple combustible emocional, las formas que asume el sufrimiento son, desde el punto de vista de las víctimas, conflictivas; asimismo indago en la forma en que se representan la politización de sus demandas, ya no como una cuestión inevitable y deseable sino como un peligro contaminante a ser evitad
Teacher Collaboratión to promote inclusive practices with cooperative learning
No full textThis study investigates how collaborative analysis of cooperative learning challenges by teachers fosters the development and implementation of inclusive improvement proposals for students with Special Educational Needs (SEN). Moreover, collaborative work among teachers has proven to be a powerful tool for professional development and also for the improvement of cooperative learning. The objective of this current research is to observe how a strategy of collaborative analysis among teachers of the problems or questions that arise in their cooperative learning practice (problems/questions) allows them to create and implement improvement proposals aimed at bettering the inclusion of these students. Employing a qualitative, multiple case study design within an action-research framework, three teacher teams from ten schools across Galicia, Valencia, Basque Country, and Catalonia (Spain) participated. Findings reveal key collaborative tasks that facilitated improvement proposal creation, including constructive collaboration on activity content and structure. Teachers also modelled strategies for inclusive student teamwork, particularly supporting students facing barriers. Notably, communicative exchanges between teachers were crucial for advancing these improvements. This research highlights the efficacy of teacher-driven collaborative analysis in enhancing the inclusion of students with Special Educational Needs (SEN) within cooperative learning environments.This work was supported by the Plan I+D+i of the Ministry of Science and Innovation: “Collaboration among teachers in the development of cooperative learning for the inclusion of the most vulnerable students [PID2021-128456NB-I00]; Jaume I University through its Research Stay Grants [E-2022-25]
Remodelling of hepatocyte cholesterol metabolism mediates Colorectal Liver Mertastasis
No full text163 p.Colorectal liver metastasis (CRLM) is the most common secondary liver cancer, and the main cause of colorectal cancer (CRC) related deaths. During CRLM, CRC cells acquire the capacity to metastasise and survive in different environments due to metabolic reprogramming. This reprogramming is obtained through the interaction between CRC cells and hepatic cells, a mechanism crucial for the priming of the pre-metastatic niche too. The results of this study showed that there is a reprogramming in cholesterol (CL) metabolism in a mouse model and patients with CRLM. In this regard, the tumour tissue (T) of patients, and the T and surrounding tissue (ST) of mice presented increased CL uptake and accumulation in the liver. Targeting CL metabolism by overexpression of Pcsk9 specifically in hepatocytes reduced CRLM development, due to the decrease of CRC cells proliferation by the secretome of those hepatocytes. Given that Pcsk9 overexpression led to increased CL biosynthesis, the accumulation of the intermediate desmosterol was induced in hepatocytes, which decreased CRC cells proliferation, both in vitro and in vivo. The proteomic analysis of the Pcsk9-overexpressing hepatocytes demonstrated that the mRNA splicing was downregulated. This process was also decreased at transcriptional level in the mouse models with reduced CRLM. Therefore, targeting CL metabolism specifically in hepatocytes reduces CRLM development through a mechanism mediated by the secretome of hepatocytes.Ane Nieva Zuluaga received a Ph.D fellowship grant from the University of the Basque Country (Basque Country, Spain) and a Scientific Exchange Grant from European Molecular Biology Organization (EMBO) for an international stay at the University Medical Center Hamburg-Eppendorf (Hamburg, Germany). This work was also funded by the Department of Health of the Basque Country, and Asociación Española Contra el Cáncer (AECC)
Optimizing operational strategies in a non-isothermal bench-scale fixed-bed reactor for CO2 hydrogenation to CH4 combining experimental and modeling and simulation approaches
No full textThe CO2 methanation reaction is a promising solution for renewable energy storage. However, the process is challenged by thermal management due to its exothermic nature, leading to hot spots that complicate reactor operation and scale-up. This study combines experimental and simulation approaches to optimize the operation of a bench-scale fixed-bed reactor. Experimental results show that reactor wall temperature, flow rate, and nitrogen dilution significantly affect temperature profiles and CO2 conversion. As a refrigeration strategy, it has been studied the use of pressurized air jackets to improve heat dissipation and stabilize the operation. A dynamic 1D heterogeneous model validated these findings and enabled simulation-based optimization. Non-uniform particle size distributions, metal loading, and SiC dilution strategies effectively mitigated hot spots without compromising CH4 yield. These results offer critical insights into reactor design, ensuring stable operation and high efficiency.This work was supported by research project PDC2022-133839-C21 and PID2022-139552OB-C21 funded by MCIN/AEI/10.13039/501100011033 and the Basque Government (IT1509-22). One of the authors (EGB) wants to acknowledge the Spanish Ministry of Universities for the salary support (FPU 20/06668)