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Water-soluble BODIPY dyes: a novel approach for their sustainable chemistry and applied photonics
No full textThe BODIPY family of organic dyes has emerged as a cornerstone in photonics research development, driving innovation and advancement in various fields of high socio-economic interest. However, the majority of BODIPY dyes exhibit hydrophobic characteristics, resulting in poor solubility in water and other hydrophilic solvents. This solubility is paramount for their optimal utilization in a myriad of photonic applications, particularly in the realms of biology and medicine. Furthermore, it facilitates safer and more sustainable manipulation and chemical modification of these expansive dyes. Nevertheless, bestowing BODIPYs with water solubility while preserving their other essential properties, notably their photophysical signatures, poses a significant challenge. In this context, we present a straightforward general chemical modification aimed at converting conventional hydrophobic BODIPYs into highly hydrophilic variants, thus enabling their efficient solubilization in water and other hydrophilic solvents with minimal disruption to the dye's inherent photophysics. The efficacy of this methodology is demonstrated through the synthesis of a number of water-soluble BODIPY dyes featuring diverse substitution patterns. Furthermore, we showcase their utility in a spectrum of photonics-related applications, including in-water BODIPY chemistry and dye-laser technology, and fluorescence microscopy.S. d. l. M. acknowledges support from Spanish MICINN, (AEI/10.13039/501100011033; research grants PID2020-114755GB-C32 and PID2024-157648-NB-C21). S. S.-B. acknowledges UCM for a pre-doctoral contract (CT58/21-CT59/21). J. B. acknowledges support from Spanish MICINN (AEI/10.13039/501100011033; research grants PID2020-114755GB-C33 and PID2024-157648-NB-C22) and Basque Government (research grant IT1639-22). C. D.-N. acknowledges Spanish MICINN for a pre-doctoral contract (PRE2018-086808). I. G.-M. acknowledges support from Spanish MICINN (AEI/10.13039/501100011033; research grant PID2023-149991NB-I00)
The Gender Gap in Science Communication on TikTok and YouTube: How Platform Dynamics Shape the Visibility of Female Science Communicators
No full textSocial media platforms facilitate the dissemination of science and access to it. However, gender inequalities in the participation and visibility of communicators persist. This study examined the differences in reach and audience response between YouTube and TikTok from a gender perspective. To do so, the ten most influential science accounts on YouTube and TikTok were selected, with the sample divided equally between men and women, to conduct a comparative study. A total of 4293 videos on TikTok and 4825 on YouTube were analyzed, along with 277,528 comments, considering metrics of views and interaction. The results show that on YouTube, men received more likes and views, while on TikTok, audience response was more balanced. The participation of women on both platforms also had a differential impact, as the number of women engaging with content on YouTube negatively correlated with interaction levels, whereas on TikTok, their impact was slightly positive. In conclusion, TikTok emerges as a more inclusive space for scientific communication, though structural challenges remain on both platforms, encouraging further research into strategies that promote gender equity in online science communication.This work is part of the scientific output of the Consolidated Research Group of the Basque University System, Gureiker (IT1496-22
Mean reversion and long memory dynamics in the Shanghai Containerized Freight Index
No full textThis paper deals with the investigation of the long memory properties of the Shanghai Containerized Freight Index for the time period from 16 October 2009 to 18 October 2024. Using fractional integration methods, we want to determine if shocks in the series have transitory or permanent effects. The results indicate that the series are very persistent when using the whole sample size with an order of integration above 1. However, if we separate three different subsamples, corresponding to the pre-Covid, Covid and post-Covid periods, we observe reversion to the mean in the pre-Covid period; however, during the Covid, there is a substantial increase in the value of d and turns decreasing after the pandemic
Temporal Structure of Music Improves the CorticalEncoding of Speech
No full textPublished on 25 March 2025Long- and short-term musical training has been proposed to improve the efficiency of cortical tracking of speech, which refers tothe synchronization of brain oscillations and the acoustic temporal structure of external stimuli. Here, we study how musical se-quences with different rhythm structures can guide the temporal dynamics of auditory oscillations synchronized with the speechenvelope. For this purpose, we investigated the effects of prior exposure to rhythmically structured musical sequences on corticaltracking of speech in Basque–Spanish bilingual adults (Experiment 1; N = 33, 22 female, Mean age = 25 years). We presentedparticipants with sentences in Basque and Spanish preceded by musical sequences that differed in their rhythmical structure.The rhythmical structure of the musical sequences was created to (1) reflect and match the syllabic structure of the sentences, (2)reflect a regular rhythm but not match the syllabic structure of the sentences, and (3) follow an irregular rhythm. Participants'brain responses were recorded using electroencephalography, and speech-brain coherence in the delta and theta bands was cal-culated. Results showed stronger speech-brain coherence in the delta band in the first condition, but only for Spanish stimuli.A follow-up experiment including a subset of the initial sample (Experiment 2; N = 20) was conducted to investigate whetherlanguage-specific stimuli properties influenced the Basque results. Similar to Experiment 1, we found stronger speech-braincoherence in the delta and theta bands when the sentences were preceded by musical sequences that matched their syllabicstructure. These results suggest that not only the regularity in music is crucial for influencing cortical tracking of speech, but sois adjusting this regularity to optimally reflect the rhythmic characteristics of listeners' native language(s). Despite finding somelanguage-specific differences across frequencies, we showed that rhythm, inherent in musical signals, guides the adaptation ofbrain oscillations, by adapting the temporal dynamics of the oscillatory activity to the rhythmic scaffolding of the musical signal.This work was supported by Ministerio de Ciencia, Innovación y Universidades (PCI2022-135031-2, PDC2022-133917-I00, PID2022-136991NB-I00, PRE2019-087623, RTI2018-096311-B-I0, RYC2018-024284-I, RYC2022-035497-I), Eusko Jaurlaritza (BERC 2022–2025, PIBA_2022_1_0015), and Agencia Estatal de Investigación (CEX2020-001010/AEI/10.13039/501100011033)
Latxa Euskarazko Hizkuntza-Eredua
No full textArtikulu honetan Latxa hizkuntza-ereduak (HE) aurkeztuko ditugu, egun euskararako garatu diren HE handienak. Latxa HEek 7.000 miloi parametrotik 70.000 milioira bitartean dituzte, eta ingeleseko LLama 2 ereduetatik eratorriak dira. Horretarako, LLama 2 gainean aurreikasketa jarraitua izeneko prozesua gauzatu da, 4.3 milioi dokumentu eta 4.200 milioi token duen euskarazko corpusa erabiliz. Euskararentzat kalitate handiko ebaluazio multzoen urritasunari aurre egiteko, lau ebaluazio multzo berri bildu ditugu: EusProficiency, EGA azterketaren atariko frogako 5.169 galdera biltzen dituena; EusReading, irakurketaren ulermeneko 352 galdera biltzen dituena; EusTrivia, 5 arlotako ezagutza orokorreko 1.715 galdera biltzen dituena; eta EusExams, oposizioetako 16.774 galdera biltzen dituena. Datu-multzo berri hauek erabiliz, Latxa eta beste euskarazko HEak ebaluatu ditugu (elebakar zein eleanitzak), eta esperimentuek erakusten dute Latxak aurreko eredu ireki guztiak gainditzen dituela. Halaber, GPT-4 Turbo HE komertzialarekiko emaitza konpetitiboak lortzen ditu Latxak, hizkuntza-ezagutzan eta ulermenean, testu-irakurmenean zein ezagutza intentsiboa eskatzen duten atazetan atzeratuta egon arren. Bai Latxa ereduen familia, baita gure corpus eta ebaluazio-datu berriak ere lizentzia irekien pean daude publiko https://github.com/hitz-zentroa/latxa helbidean.; We introduce the Latxa family of Large Language Models (LLMs), currently the largest developed for Basque. Latxa models range from 7 to 70 billion parameters and are built on LLama 2 models, which we continued pretraining on 4.3 million documents and 4.2 billion tokens of Basque. To address the scarcity of high-quality evaluation benchmarks for Basque, we collected four new datasets: EusProficiency, comprising 5,169 Atarikoa test questions of EGA exams; EusReading, comprisinsg 352 reading comprehension questions; EusTrivia, with 1,715 general knowledge questions across 5 areas; and EusExams, comprising 16,774 questions from public office exams. We conducted evaluations of Latxa and other LLMs (both monolingual and multilingual), with results showing Latxa's superiority over previous open models. Latxa also obtains competitive results with the commercial GPT-4 Turbo in language proficiency and understanding, despite lagging behind in reading comprehension and knowledge-intensive tasks. Both the Latxa model family, and our pretraining and evaluation data are publicly available under open licenses
Individual factors of expected and unexpected sexting and the subsequent feelings: A nationally representative study in adolescents
No full textSexting is prevalent among adolescents, yet we lack an understanding of adolescents’ responses to its various forms and the factors that may drive those responses. This study adopts an integrative media effects framework and a nationally representative sample of Czech adolescents (11–16 years old, N = 2500, 50% girls) to investigate: (1) the associations between depression, loneliness, self-esteem, happiness, sensation seeking, age and gender, and the different types of sexting behavior (both expected and unexpected receiving and sending of sexts); and (2) the role of individual factors in feeling happy and upset after different types of sexting. While we found a similar pattern for the associations of individual factors with engagement in the three sexting behaviors, we found no pattern for the associations across the outcomes (i.e. feeling happy and upset). Our findings show that the outcomes of sexting must be researched as individual behaviors, not as one “sexting” behavior.The author(s) disclosed receipt of the following financial support for the research, authorship, and/
or publication of this article: The results of this project LL2304 were obtained with financial support
from the Ministry of Education, Youth and Sports within the targeted support of the ERC CZ
program
From intention to perception: emotional processes as a link between intended and perceived leadership styles
No full textIntroduction: Research has shown that managers and employees often differ in
their perceptions of leadership, and that agreement between them is essential
for effective leadership. Leadership involves both the actions of leaders and
the perceptions of followers who interpret those actions within organizational
contexts. Thus, the extent to which intended leadership styles influence followers—
and, consequently, organizations—may depend largely on followers’ perceptions.
It is therefore important to analyze the relationship between leaders’ intended
leadership styles, followers’ perceptions of leadership, and the mediation processes
between them. This study explored the mediating effects of management team
emotional intelligence (TEI), the discrete emotions of followers and work units,
and their roles in linking intended and perceived leadership styles.
Methods: Data were collected from two sources: 1,566 managers organized
into 188 teams, and 4,564 workers. Multilevel path analysis was used to examine
the relationships among variables.
Results: The findings showed that TEI and employees’ emotional states fully
mediated the relationship between management teams’ intended transformational
leadership and employees’ perceived transformational leadership.
Discussion: This study highlights the central role of emotional processes in
leadership effectiveness. TEI in management teams enhances the impact of
intended transformational leadership (TFL) by shaping followers’ emotional
states and perceptions. Positive, high-intensity emotions strengthen perceptions
of leadership, whereas low-intensity states, such as comfort, weaken them.
These findings advance our understanding of how leaders’ emotional skills and
group affect contribute to creating more transformational leadership processes.The author(s) declare that financial support was received for the research and/or publication of this article. This study was supported by the University of the Basque Country (PIF2016/195) as well as by the Provincial Council of Gipuzkoa, Department of Economical Promotion, Tourism and Rural Context (Talent and Learning-Bateratzen-Trans 109/2020)
Between the global and the local: socio-legal articulations of Madrid Nuevo Norte Project
No full textMadrid wants to compete with the big global cities articulated within the interests of transnational finantial capital by adapting to the new economic and social transformation of the last recent decades. The Madrid Nuevo Norte project is presented as a strategic solution to achieve these aims by reconnecting fragmented urban areas and implementing sustainable innovation in its development process. However, since the project is led by a private agent together with the Council of Madrid in a private-public partnership agreement, this raises the hypothesis that urban legality, as a non-neutral tool, is subordinated to private interest, weakening the right to the city and aggravating socio-spatial inequalities. This study questions how law operates not just as a regulation device but as an active urban space producer that is instrumentalized to legitimize spatial exclusive reconfigurations. The starting point of this study is the analysis of the legal and discursive apparatus of Madrid Nuevo Norte by sources as the main normative documents that support the project and official narratives extracted from journal articles and the discourse of the main stakeholder of the project itself. The aim of this article is to identify how legal and discursive production of space articulates tensions between urban governance, right to the city and socio-spatial justice. This analysis allows us to conclude that urban legality is instrumentalized as a technology for social order under capital interests since law enables the subordination of public goods to private profitability
Model Predictive Torque Control
No full textThis thesis presents a comparative analysis of torque control techniques where classical PI(D)s and PWM control methods based inner current controllers are implemented for electric motors. In these cases, sampling frequency of the controller is usually equal or twice the frequency of the triangular wave of PWM modulator and the switching frequency is fixed. If an improved bandwidth of the control loop is required, at least two options exist; use other controllers than PI or implement controller where the sampling frequency of the controller and the average switching frequency can differ. Therefore, other additional control methods should be analysed: Direct Torque Control (DTC) with hysteresis controllers and Model Predictive Torque Control (MPTC) with Finite States (FS-MPTC).
Overall, this study is introduced with a literature review of these control strategies, highlighting their theoretical foundations and practical implementations. Furthermore, simulations in Simulink are utilised to validate theoretical findings, providing quantitative comparisons of the methods under various operating conditions for switching frequency analysis. Finally, the performance during steady state conditions is evaluated in terms of torque, flux and current ripple, and voltage switching pattern. Finally, an analysis of torque dynamic response is executed for the three methods.
The results of this research aim to provide insights into the advantages and limitations of each method, assisting in the selection of an optimal torque control strategy for high-performance electrical drives. The study concludes with recommendations on the applicability of MPTC technique for electric drives and considerations about implementation feasibility of this method.Esta tesis presenta un análisis comparativo de técnicas de control de par en motores eléctricos, enfocándose en controladores de corriente internos clásicos PI(D) y métodos PWM. La frecuencia de muestreo del controlador suele ser igual o el doble de la frecuencia de la onda triangular del modulador PWM, con una frecuencia de conmutación fija. Para mejorar el ancho de banda del sistema de control, se proponen dos opciones: utilizar controladores distintos a PI o implementar un controlador con frecuencias de muestreo y de conmutación que puedan diferir. Se analizan métodos adicionales como el Control Directo de Par (DTC) con controladores de histéresis y el Control de Par Predictivo por Modelo (MPTC) con Estados Finitos.
El estudio comienza con una revisión de la literatura sobre estas estrategias, destacando sus bases teóricas e implementaciones prácticas. Se utilizan simulaciones en Simulink para validar los hallazgos teóricos, ofreciendo comparaciones cuantitativas bajo diferentes condiciones operativas. Se evalúa el rendimiento de los tres métodos en estado estacionario, considerando el par, el rizado del flujo, la corriente del estator y el patrón de conmutación de la tensión. También se realiza un análisis de la respuesta dinámica del par, ajustando las condiciones de funcionamiento y los parámetros de los métodos.
Los resultados buscan ofrecer información sobre las ventajas y limitaciones de cada técnica, facilitando la elección de una estrategia óptima de control de par para accionamientos eléctricos de alto rendimiento. La investigación concluye con recomendaciones sobre la aplicabilidad del MPTC en estas aplicaciones y reflexiones sobre su viabilidad de implementación.Tesi honek motor elektrikoen indar-paren kontrol tekniken azterketa konparatibo bat aurkezten du, PI(D) kontrolatzaile klasikoetan eta PWM metodoetan oinarrituz. Kontrolatzailearen lagin maiztasuna normalean modulador PWM-ren triangelu uhinaren frekuentzia berdina edo bikoitza izaten da, eta aldi berean, aldatze frekuentzia finkoa da. Kontrol sistemaren banda zabalera hobetzeko, bi aukera proposatzen dira: PI baino bestelako kontrolatzaileak erabiltzea edo lagin maiztasunaren eta aldatze maiztasunaren arteko desberdintasunak onartzen dituen kontrolatzaile bat ezartzea. DTC (Direct Torque Control) histerezis kontrolatzailekin eta MPTC (Model Predictive Torque Control) Estatuekin metodo osagarriak aztertzen dira.
Ikertzeak estrategia hauen literatura azterketa batekin hasten da, oinarri teorikoak eta praktiken nabarmentzearekin. Simulink-en simulazioak erabiltzen dira aurkikuntza teorikoak balioztatzeko, funtzionamendu baldintza desberdinetan kuantitatiboki konparazioak eskainiz. Hirugarren metodoen errendimendua egoera estatsionarioan ebaluatzen da, indar-parea, fluxuaren irizpideak, estatorearen korrontea eta tentsioaren aldatze patroiak kontuan hartuz. Gainera, indar-parearekin erantzun dinamikoa aztertzen da, funtzionamendu baldintzak eta metodoen parametroak doitzeko.
Emaitzek teknika bakoitzaren abantailak eta mugak ezagutzen laguntzea dute helburu, indar-parearen kontrol estrategiaren aukeraketa errazteko. Ikertzeak MPTC-ren aplikagarritasunari buruzko gomendioekin eta teknologia honen ezarpenaren bideragarritasunari buruzko gogoetarekin amaitzen du
Beldurra gaur egungo euskal haur literaturan: didaktika, literatura eta emozioa
No full text58 p. -- Bibliogr.: p. 35-37[EUS] Gradu Amaierako Lan honetan beldurraren emozioaren lanketa hartu da aztergai, haur literatura ardatz hartuta. Lan honen helburua gizakion funtsezko emozioa den beldurraren kontzeptua eta haren dimentsio nagusiak sakon aztertzea izango da, haur eta gazte literaturaren testuinguruan kokatuta. Horretarako, oinarri teoriko sendoa garatu, eta ikerketa bat burutu da, non beldurra piztea helburu duten liburuak eta beldurra lantzea helburu duten liburuak bildu eta aztertu diren. Ikerketa honetan honako alderdi hauek aztertu dira: beldur mota (erreala edo fantastikoa), pertsonaien ezaugarriak, beldurraren irudikapena eta istorioen amaiera motak. Ikerketaren amaieran, hasierako hipotesiak lortutako emaitzekin alderatu dira, eta ondorio nagusiak eta hausnarketa pertsonala garatu da. Azkenik, bai ikerketaren bai lanaren hobekuntza-proposamenak aurkeztu dira.[ES] En este Trabajo de Fin de Grado se analiza el tratamiento del miedo en el ámbito de la literatura infantil. El objetivo principal del trabajo es analizar la relación entre el miedo y la literatura infantil, y cómo se puede utilizar ésta como herramienta pedagógica para comprender, trabajar y gestionar dicha emoción. Para ello, se ha desarrollado una sólida base teórica y se ha llevado a cabo un estudio en el que se han recopilado y analizado libros que, por un lado, buscan despertar el miedo en los lectores y lectoras, y, por otro, ofrecer herramientas para enfrentar dicha emoción. En este estudio se han analizado los siguientes aspectos: el tipo de miedo (real o fantástico), las características de los personajes, la representación del miedo y los tipos de final de las historias. Al final de la investigación, se han comparado las hipótesis iniciales con los resultados obtenidos, lo que ha permitido desarrollar las principales conclusiones y la reflexión personal. Por último, se han presentado propuestas de mejora tanto para la investigación como para posibles futuros trabajos