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Permanent URI for this collectionhttps://hdl.handle.net/10272/24220

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Differential Contribution of Drug Classes to Impulsive Behaviors in Patients Diagnosed with Substance Use Disorder
(Springer, 2026) Díaz López, Alba; Lozano Rojas, Óscar Martín; Moraleda Barreno, Enrique; Velo Ramírez, María Sheila
Purpose of review: This paper synthesizes recent evidence on the differential contribution of drug classes to impulsive behaviors in patients with substance use disorder. It focuses on delineating which domains of impulsivity vary by substance class, which impulsivity dimensions predict treatment outcomes, and the principal neurobiological findings. Recent findings: Recent studies report elevated impulsivity across most substance use disorders with substance-specific patterns. Stimulants, particularly methamphetamine, produce the most pervasive deficits in inhibitory control, planning, and decision-making. Alcohol and opioids are associated with broad decision-making impairments and elevated trait impulsivity that often persist during substitution treatments. By contrast, cannabis shows the weakest and most inconsistent effects.Impulsive decision-making consistently predicts relapse. Neuroimaging implicates frontostriatal circuits, the insula, and the cingulate cortex, with substance-specific differences in regional volume, receptor availability, and network connectivity. Genetic evidence is limited and heterogeneous. Summary: Impulsivity is a transdiagnostic marker with substance-specific profiles that influence both relapse risk and treatment response. Longitudinal, comparative, and network-focused studies employing consensus measures are needed to clarify causality and inform personalized interventions.
An Approach to Acclimation Mechanisms of the Extremotolerant Cyanobacterium Chroococcidiopsis sp. to Increasing Red-Light Irradiances
(MDPI, 2026) Robles Garrido, María; Beltrán Peguero, Verónica; Garbayo Nores, Inés; Wierzchos, Jacek; Vílchez Lobato, Carlos
Chroococcidiopsis sp. was isolated from the endolithic habitat of the Atacama Desert (northern Chile), one of the most challenging-to-life polyextreme environments on Earth. The photosynthetic machinery of microorganisms inhabiting this environment is supposed to be highly adapted to cope with the intense solar radiation of the area. Thus, PAR-red light ranging from 100 to 900 µmol photon·m−2·s−1 has been investigated as a strategy to enhance culture productivity and stimulate the synthesis of bioactive molecules in Chroococcidiopsis sp. A control culture was maintained under white light at 100 µmol photon·m−2·s−1. The results revealed that red light was utilized more efficiently than white light of similar irradiance, and its modulation enhanced both growth and photosynthetic activity of the cyanobacterium. Furthermore, Chroococcidiopsis sp. appeared to activate mechanisms to mitigate photooxidative stress produced by excess light energy. Specifically, increasing light irradiance induced photoacclimation responses, characterized by a decrease in chlorophyll content and a concomitant increase in carotenoid accumulation, likely aimed at reducing photon flux transduced to photosynthesis. Additionally, scytonemin synthesis was enhanced under high irradiances, contributing to dissipating excess light energy. Overall, this study demonstrates that modulation of red-light irradiance effectively improves the growth of Chroococcidiopsis sp. while promoting the accumulation of antioxidant compounds—primarily carotenoids and, to a lesser extent, scytonemin.
Early Cytokine Profiles in Critically Ill Patients with COVID-19 and Their Association with Mortality
(MDPI, 2026) Gamarra Morales, Yenifer; Molina López, Jorge; Machado Casas, Juan Francisco; Herrera Quintana, Lourdes; Vázquez Lorente, Héctor; Pérez Villares, José Miguel; Planells, Elena
Background/Objectives: The purpose of this study was to (i) determine the levels of interleukins in patients with COVID-19 admitted to the Intensive Care Unit (ICU) and (ii) evaluate their early dynamics, as well as (iii) assess their relationships with morbidity and mortality. Methods: This was a prospective analytical study of critically ill patients with COVID-19 who were monitored from admission to three days of stay in the ICU. Circulating levels of IL-1β, IL-2, IL-6, IL-7, IL-8, IL-10, and tumour necrosis factor-alpha (TNF-α) were measured. Cytokine levels were analysed in relation to clinical severity parameters and 28-day mortality. Results: A dynamic cytokine response was observed during the first 72 h, with a significant increase in TNF-α levels and a decrease in IL-10 and IL-1β. Non-survivors showed higher TNF-α levels than survivors. In the multivariable analysis adjusted for clinical severity, TNF-α remained independently associated with 28-day mortality, whereas other cytokines did not retain statistical significance. The overall predictive performance of cytokines was moderate. Conclusions: Early cytokine dynamics reflect the evolving inflammatory response in critically ill COVID-19 patients. TNF-α emerges as an independent predictor of mortality, supporting its role as a relevant biomarker of adverse outcomes. Although its predictive capacity is moderate, TNF-α may provide clinically meaningful information for risk stratification when integrated with established clinical and laboratory parameters.
Competency Profile of Social Work in Educational Institutions: An Empirically Derived Three-Factor Framework
(Taylor and Francis Group, 2026) Fernández Martínez, María Mar; Ibáñez López, Andrea; Luque de la Rosa, Antonio
Purpose: This study aims to empirically define the competency profile of social work professionals in educational institutions by identifying and structuring core competencies that articulate their professional role within the educational system. Materials and methods: A quantitative descriptive-exploratory design was employed. Data were collected from 859 participants (students and graduates linked to Andalusian universities). An initial 24-item questionnaire was developed and subsequently refined through statistical analysis. Confirmatory factor analysis (CFA) was conducted to examine the factorial structure of the instrument. Results: The analysis resulted in a factorial structure comprising 15 competencies organized into three interrelated factors: competencies related to work with teaching staff, competencies focused on students, and competencies oriented toward families. The model demonstrated satisfactory goodness-of-fit indicators, supporting the internal coherence and empirical consistency of the proposed competency framework. Discussion: Findings contribute to clarifying the professional role of social work within educational institutions by providing an empirically grounded structuring of competencies. The results address the existing gap between the discursive recognition of school social work and the limited systematic delimitation of its competency profile. Conclusion: This study offers an evidence-based competency framework that strengthens the alignment between university training and professional practice, contributing to the disciplinary delimitation and institutional positioning of social work in educational contexts.
Development and Psychometric Evaluation of the Scale of Externalizing Problem Behaviors in Adults (SEPBA): A Hybrid Dimensional–Categorical Instrument
(Fundación López Ibor, 2026) Torres Rosado, Lidia; Lozano Rojas, Óscar Martín; Díaz Batanero, María Carmen; Barba Durán, Raúl; Sánchez García, Manuel
Background: The Scale of Externalizing Problem Behaviors in Adults (SEPBA) was developed as a hybrid psychometric instrument designed to assess both dimensional traits and categorical diagnoses associated with externalizing psychopathology. Based on an integrative operational framework drawing on Diagnostic and Statistical Manual of Mental Disorders (DSM-5) and the Hierarchical Taxonomy of Psychopathology (HiTOP) model, the SEPBA assesses 15 traits/facets and 6 disorders within the domains of antagonism and disinhibition. Methods: The present study analyzed the psychometric properties of the SEPBA in a combined community and prisoner sample (n = 922). The final version of the SEPBA included 144 items rated on a 4-point Likert scale. Reliability (α, ω), item discrimination, convergent/discriminant validity, confirmatory factor analyses, and gender measurement invariance were examined. Results: The results indicated adequate item discrimination and internal consistency across all scales. Confirmatory factor analyses supported the unidimensionality of the individual scales and the hypothesized hierarchical organization of traits and facets. Gender invariance of the measure was demonstrated. In addition, evidence of convergent and discriminant validity was provided through correlations with external measures. Conclusion: The findings support the SEPBA as a suitable assessment instrument. Its hybrid structure offers an integrative approach to transdiagnostic assessment, enhancing both the clinical utility of categorical diagnoses and the empirical applicability of dimensional profiles for assessing externalizing behaviors in adults.
Spain's decarbonisation to 2030: An integrated LMDI–LEAP assessment
(Elsevier, 2026) Cámara Aceituno, Juan; Galán Cano, Lucía; Unión Sánchez, Juan de Dios; Hermoso Orzáez, Manuel Jesús; Mena Nieto, Ángel Isidro; Terrados Cepeda, Julio
Spain’s National Energy and Climate Plan (PNIEC) requires deep decarbonisation, yet it remains unclear whether current trends are sufficient to meet the 2030 targets. This study integrates an LMDI decomposition of energyrelated CO2 emissions (1990–2024), aligned with PNIEC sector categories, with a trend-based LEAP projection to 2030, and benchmarks results against the official PNIEC targets. The LMDI analysis shows that economic activity is the main upward driver of emissions, while energy-efficiency improvements and cleaner fuel substitution exert mitigating effects; however, transport and industry exhibit persistent inertia. Under the Baseline scenario, the TES-based CO2 proxy reaches −15.8% relative to 1990 by 2030, far from the PNIEC target of −32.0% (a 16.2 percentage-point gap). Supply-side progress outpaces demand-side transformation: renewable electricity reaches 89.0% of generation versus the 81.0% PNIEC benchmark, whereas electrification in final energy reaches only 25.8% versus the 35.0% target, leaving most of the gap concentrated in diffuse end-use sectors. These findings provide a transparent diagnostic framework for identifying where additional measures are required to align Spain’s current trajectory with its 2030 decarbonisation commitments.
Capturing subjectivity: A weighted ensemble approach to preserve annotator diversity
(Elsevier, 2026) Vázquez Ramos, Laura; Mata Vázquez, Jacinto; Pachón Álvarez, Victoria
Subjective linguistic tasks, such as sexism detection or sentiment analysis, often involve substantial disagreement among human annotators, reflecting genuine interpretive diversity rather than annotation noise. Traditional aggregation methods, most commonly majority voting, enforce a single reference label and an artificial consensus. This is problematic because it discards information about how different groups of people interpret the same content, thereby obscuring nuances that are crucial for understanding the phenomenon under study. This paper introduces a perspectivist framework that explicitly models annotator diversity by training independent classifiers based on demographic variables and subsequently combining them through a weighted ensembling strategy. Each perspective is assigned a relative importance according to its individual performance (𝐹1-score), and the decision threshold is optimised to maximise the overall 𝐹1-score of the ensemble. Experiments conducted on three datasets-EXIST Texts 2024, EXIST Memes 2024, and a re-annotated version of SST-2-show consistent improvements across all tasks. The weighted ensemble achieves an 𝐹1-score of 0.84 on EXIST Texts, improves performance from 0.84 to 0.91 on EXIST Memes, and attains an 𝐹1-score of 0.95 on the re-annotated SST-2 dataset. These results demonstrate that weighted perspectivist ensembling achieves a better balance between precision and recall than both individual models and standard baselines, while preserving human interpretive diversity. They highlight the potential of perspectivist modelling as a pathway towards fairer and more robust NLP systems that are better aligned with human variability.
The smartphone addiction degree estimation scale: Enhancing assessment and understanding of gender differences in youth
(Elsevier, 2026) Batista Foguet, Joan Manuel; Mendoza Berjano, Ramón; Losada Cavestany, Inés
Current psychometric instruments for assessing smartphone addiction often fail to account adequately for age and gender differences, largely due to their reliance on traditional factor analytic approaches. This study employs a sequential application of Factor Analysis and Item Response Theory to develop a brief smartphone addiction scale for individuals aged 18–25 that can be flexibly applied according to the severity of addiction exhibited by the individual. The original 42-item questionnaire was administered to a sample of 1994 European university students. Results supported a three-factor structure consistent with core components of substance addiction: Tolerance/Control Deficit, Withdrawal Syndrome, and Negative Consequences. A fourth factor related to physical and health consequences was successfully integrated into the Negative Consequences factor without compromising model fit or reliability. The incorporation of Item Response Theory enhanced measurement precision by transforming the instrument into an adaptive test capable of estimating smartphone addiction severity based on individual response patterns. The final scale retained 20 of the original 42 items while maintaining strong psychometric properties. Application of the scale to the analysis of gender differences in smartphone addiction demonstrated that substantive conclusions vary depending on the analytical framework employed, helping to explain inconsistencies reported in the existing literature. Gender-specific analyses indicated that men were more likely to report productivity loss and reduced social opportunities, whereas women more frequently endorsed smartphone use as a strategy for coping with negative emotional states. Overall, the proposed Smartphone Addiction Degree Estimation Scale (SADES) shows strong potential as a reliable tool for epidemiological research and for informing public health interventions targeting problematic smartphone use.
Effect of nanoparticle concentration on non-aqueous paraffin pickering emulsions in PEG400 for efficient thermal energy storage
(Elsevier, 2026) Sanabria Sanabria, Sebastián; Delgado Sánchez, Clara; Tenorio Alfonso, Adrián; Cuadri Vega, Antonio Abad; Navarro Domínguez, Francisco Javier
The development of non-aqueous phase change material emulsions (PCMEs) for thermal energy storage holds significant potential, as it enables the extension of the operating temperature range beyond the freezing and boiling points of water. Nevertheless, achieving stable and processable formulations remains a significant challenge. In this regard, this research presents the formulation and characterization of anhydrous Pickering emulsions, in which a selected paraffin (melting point 58–60 °C) serves both as the dispersed phase and as the phase change material (PCM), while polyethylene glycol (PEG 400) constitutes the continuous phase. The emulsions were stabilized with hydrophobized pyrogenic silica nanoparticles, and the influence of nanoparticles concentration on emulsion morphology, rheology, and thermal properties was evaluated. Characterization techniques included optical microscopy, steady-state flow measurements, oscillatory tests, and modulated differential scanning calorimetry (MDSC). The results demonstrate that the nanoparticles successfully stabilize the emulsions and enhance their rheological properties, which is attributed to internal structuring mechanisms. Additionally, only minimal supercooling was detected in the samples. Overall, the formulated emulsions exhibit tuneable properties and offer a promising platform for the design of PCME systems capable of stable operation at elevated temperatures, including applications in solar–thermal energy capture.
A potential meteorite-producing Taurid fireball observed in 2021
(Oxford University Press; Royal Astronomical Society, 2026) Madiedo Gil, José María
On 2021 November 12, a Taurid fireball with an absolute magnitude of −13 was recorded over Spain. This work presents the analysis of this impressive bolide, which penetrated the atmosphere till a remarkable low final height of about 25.1 km above the ground level. A non-zero mass was calculated at the ending point of the luminous trajectory, which means that this event would have produced a meteorite that fell on the ground. Despite the mass of the fragment being small, of around 6.5 g, this would confirm the possibility of Taurid meteorite survival, a debate that was initiated some years ago. The emission spectrum of this fireball is also discussed.
Gender-related differences in structural pathways involving alcohol-related aggressive behaviors, family conflicts, and Cluster B personality disorders in substance use treatment: engagement, discharge, and readmissions
(Elsevier, 2026) Dacosta Sánchez, Daniel; González Ponce, Bella M.; Mancheño Velasco, Cinta; Narváez Camargo, Marta; Lozano Rojas, Óscar Martín
Background: Gender-informed addiction care needs evidence on whether alcohol-related aggressive behaviors, family conflict and Cluster B pathology influence treatment differently for men and women. Objective: To test gender-specific structural pathways associating years of problematic alcohol use, alcohol-related aggressive behaviors, partner conflict, child conflict and Cluster B diagnosis with appointment adherence, retention, therapeutic discharge and readmissions. Method: Retrospective electronic health record study in Andalusia’s public addiction treatment network (N = 4844 entrants, 2015–2021; 25.5% women). Multigroup structural modelling tested within-gender associations and gender differences in pathways to outcomes. Results: Child conflict was more prevalent in women than men (31.7% vs 15.9%; V = 0.17; p < 0.001) and was associated with higher readmissions in women (β = 0.101; p = 0.001) but not men (β = -0.029; p = 0.126); partner conflict was associated with fewer readmissions in men (β = -0.041; p = 0.019). In men, alcohol-related aggressive behaviors were associated with lower appointment adherence (β = -0.059; p = 0.001). Cluster B diagnosis was associated with lower therapeutic discharge (men: β = -0.063; p = 0.017; women: β = -0.138; p = 0.005) and higher readmissions (men: β = 0.062; women: β = 0.095; both p < 0.001). Retention was associated with higher discharge and fewer readmissions in both genders (all p < 0.001). Meaningful gender-specific structural differences emerged only in the pathway associating child conflict to readmissions. Discussion and conclusion: These pathways highlight child conflict as a gender-specific readmission risk marker for women and support family-focused, gender-informed interventions that strengthen adherence and retention.
Unveiling Medusozoan Fossil patterns: A statistical and spatial study of the lower Cambrian Site in Constantina, Spain
(Elsevier, 2026) Moclán, Abel; Velázquez Tello, Alejandro; Correa Cano, José Ángel; Mayoral Alfaro, Eduardo
A new approach, applying different statistical methods to the early Cambrian medusozoan site of Constantina (Seville, Spain), has allowed the establishment of new biometric parameters for the specimens, a more precise determination of the number of imprints—both subumbrellar and exumbrellar forms—and the deduction of their main taphonomic characteristics. A total of 275 specimens have been identified, with exumbrellar forms (morphotype B) being the most frequent (92%) and having the smallest average length (24.91 cm), while subumbrellar forms (morphotype A) are larger on average (38.29 cm). This new registry represents a record three times greater than previously considered, with the sample characterised by specimens with an average length of 25.93 cm. The analysis of the length/width ratio shows a very strong and statistically significant correlation, implying isometric growth of the medusozoans, consistent with their adult stage. Most specimens exhibit a clear NW-SE orientation, which is parallel to the dominant direction of the palaeocurrents, suggesting that they were reoriented as they were pushed toward the coast before deposition. Additionally, most fossils are clustered in two distinct areas of the surface with very high density, indicating the presence of a common accumulation agent for the entire assemblage. Finally, the analysis of the expanded spatial window through spatial modelling has led to the identification of up to 16 additional specimens that had not been confirmed or were of uncertain identification.
Sequential cascade biorefinery for the valorization of spent coffee grounds: Energy, biodiesel, furfural, and biochar production
(Elsevier, 2026) Loaiza Rodríguez, Javier Mauricio; Palma López, Alberto; García Domínguez, Juan Carlos; Díaz Blanco, Manuel Jesús; Alfaro Martínez, Ascensión
This study presents a sequential biorefinery approach for the integrated valorization of spent coffee grounds (SCG) within a circular economy framework. The process comprises multiple operational units. Initially, SCG are pelletized for direct combustion, demonstrating promising energy potential. In the second unit, coffee oil is extracted via Soxhlet using hexane, isopropanol, and ethanol, and subsequently converted into biodiesel through transesterification, yielding a biofuel with a favorable fatty acid profile. The third unit involves ultrasound-assisted cold alkaline extraction (CAE) of the residual solid to selectively recover hemicelluloses with minimal degradation. Optimal CAE conditions (40 °C, 90 min, 100 g L−1 NaOH) enhanced hemicellulose yield while maintaining high calorific value (21.529 kJ kg−1), comparable to the raw material (21.560 kJ kg−1). The hemicellulose-rich liquor was subjected to acid hydrolysis for furfural production, with maximum yield (590.3 mg L−1) achieved under central experimental conditions (2% acid, 160 °C). The solid residue from hydrolysis underwent pyrolysis to produce biochar. Kinetic analysis of the pyrolysis process using the Flynn–Wall–Ozawa method on TGA data enabled determination of activation energy without assuming a specific reaction model. The results confirm the feasibility of integrating thermochemical and biochemical pathways for SCG valorization, supporting the development of sustainable biorefineries and contributing to renewable energy and chemical production within circular economy strategies.
Measurement of Soil Moisture Using Capacitance Measurements: Development of a Low-Cost Device for Environmental and Very-Low-Enthalpy Geothermal Energy Applications
(MDPI, 2026) Pino Fernández, Joaquín del; Martínez Bohórquez, Miguel Ángel; Andújar Márquez, José Manuel; Roca Prieto, Manuel Jesús; Enrique Gómez, Juan M.
Measuring soil moisture is crucial for optimizing agricultural irrigation, but also, from an energy efficiency standpoint, for the proper design of very-low-enthalpy geothermal energy (VLEGE) facilities. VLEGE represents a renewable energy resource with great potential for residential and industrial applications, as it can provide heating and cooling with high energy efficiency and minimal environmental impact. Soil moisture plays a decisive role in the thermal performance of VLEGE facilities, where small variations in water content can significantly alter the thermal conductivity of the soil and, consequently, the efficiency of their horizontal heat exchangers. This paper presents a low-cost capacitive soil moisture sensor featuring optimized interdigitated electrodes and a controlled dielectric coating that ensures mechanical and electrical stability in subsurface environments. The novelty of this work lies in the validated integration of optimized IDE design, dielectric protection, embedded capacitance acquisition, and gravimetric calibration into a low-cost soil water content measurement device for environmental, agricultural, and VLEGE applications. The developed system converts capacitance variations into direct estimates of soil water content through an integrated microcontroller-based signal-conditioning stage. The developed device is robust, reliable, and readily reproducible. Furthermore, given its low cost (around €50 if manufactured manually; mass-produced it would be much cheaper) and its excellent sensitivity and precision, it is ideal for setting up continuous monitoring networks, even for domestic applications, both in VLEGE installations and in other application domains, such as agriculture and environmental monitoring, where soil moisture measurement is a crucial parameter. This work contributes to the development of more efficient and accessible solutions for harnessing geothermal energy, particularly in installations where dynamic tracking of soil moisture is essential to ensure stable long-term performance.
Estrategias transmedia en educación lectora: un estudio sistemático
(Fundación iS+D para la Investigación Social Avanzada, 2026) Peña Acuña, Beatriz; Alfonso Jaramillo, José Francisco
La educación transmedia ha emergido en los últimos años como una metodología innovadora que integra la multimodalidad a través de múltiples plataformas y formatos digitales con el objetivo de enriquecer las experiencias de aprendizaje. Esta revisión sistemática, realizada conforme a las directrices PRISMA 2020, examina la relación entre la lectura y la educación transmedia en publicaciones académicas en español e inglés indexadas en Web of Science, Scopus y ERIC durante el periodo comprendido entre 2020 y 2025. Los resultados muestran que las estrategias transmedia favorecen la comprensión lectora al estimular el desarrollo de habilidades críticas, digitales y multimodales. Asimismo, se identificaron beneficios adicionales como el incremento de la motivación estudiantil, la consolidación de aprendizajes significativos y el fortalecimiento de competencias colaborativas en distintos niveles educativos. No obstante, también se señalaron desafíos relevantes, entre ellos la necesidad de una formación docente específica, la carencia de marcos pedagógicos claros que garanticen aprendizajes efectivos y las limitaciones tecnológicas que afectan especialmente a contextos desfavorecidos. Estos hallazgos reflejan tanto el potencial como las limitaciones de la educación transmedia. En la discusión, la evidencia sugiere que las prácticas transmedia permiten conectar las actividades educativas con los hábitos mediáticos contemporáneos, promoviendo aprendizajes activos, creativos y colaborativos. Sin embargo, para lograr una implementación efectiva se requiere una planificación cuidadosa, preparación docente y adaptación de los recursos a la realidad tecnológica de cada contexto. En conclusión, la educación transmedia se consolida como una estrategia prometedora para fortalecer la competencia lectora, aunque persisten retos como la brecha digital y la necesidad de marcos pedagógicos sólidos. Se recomienda que futuras investigaciones profundicen en su impacto a largo plazo y exploren su aplicación en etapas educativas menos estudiadas, contribuyendo así a una integración más equitativa y sostenible de la transmedia en la didáctica de la lectura.
Eastern white pine ring proxies show potential for climate reconstruction in a Canadian temperate forest
(Elsevier, 2026) Labrecque Foy, Julie Pascale; Lemay, Marc-André; Gennaretti, Fabio; Boucher, Étienne; Arseneault, Dominique; Montoro Girona, Miguel
High-resolution climate reconstructions are needed to understand past and future climate–vegetation dynamics. However, climate reconstructions using ring width are scarce in temperate regions where climate has limited impacts on tree growth. In T´emiscamingue, white pine sunken logs represent valuable archives for long-term climate reconstructions, but white pine’s response to climate variations in this temperate region is unknown. Moreover, the most suitable proxies for climate reconstruction in white pine—ring widths or stable isotopes— remain unclear. This study evaluates which proxy, or combination of proxies, best captures climate signals in white pine radial growth across contrasting soil drainage conditions. Ring widths were measured in 60 trees from Opemican National Park (30 on each of fast and moderate drainage conditions). Carbon and oxygen isotope ratios were analyzed from five trees per site over the period 1950–2020. Climatic data from ERA5 were used to calibrate response functions. June-August drought index (SPEI) as well as June-July precipitation and temperature were the dominant climatic drivers on all proxies, regardless of drainage type. Bayesian linear models revealed that combining carbon isotopes with ring-width data provided the most robust reconstruction of June–July precipitation (r = 0.43), that combining oxygen isotopes with ring widths yielded the best reconstruction of June–July temperatures (r = 0.49), and that combining carbon and oxygen isotopes produced the best reconstruction of June-August SPEI (r = 0.45). This study is among the first to demonstrate the potential of a multi-proxy approach for climate reconstruction using white pine. Our results provide insights that may guide future climate reconstructions in temperate regions, where tree species with lower climate sensitivity could also be considered.
Estimation of Two-States Proportional Hazard Rates Models with Unobserved Heterogeneity
(MDPI, 2026) Congregado Ramírez de Aguilera, Emilio; Troncoso Ponce, David; Rubino, Nicola; Morales Kirioukhina, Alejandro
This article examines two-state proportional hazard rate models with unobserved heterogeneity specific to each state, a framework that is especially relevant for labor market transitions. To make estimation feasible in large longitudinal datasets, we implement hshaz2s, a Stata routine that uses analytical expressions for the gradient vector and Hessian matrix of the log-likelihood function through the dual second-order moment (d2 ml) method. The empirical application estimates a discrete-time duration model for transitions between employment and unemployment using Spanish labor market microdata for young low-skilled workers over 2000–2019. The results show that apprenticeship contracts are associated with lower exit rates from employment than other temporary contracts, but not with faster transitions from unemployment back into employment. The estimates also reveal substantial state-specific unobserved heterogeneity, with a large latent group characterized by persistent spells in both states. Analytical second-order information also markedly reduces convergence time under richer heterogeneity structures. Overall, the article makes this class of two-state hazard models operational for applied research and provides new evidence on apprenticeship and temporary contracts in Spain.
Relationship between motivation, intensity, performance and physical fitness in youth athletes
(Universidad de Extremadura; Federación Extremeña de Balonmano, 2025) Sáenz-López Buñuel, Pedro; García Ceberino, Juan Manuel; Fierro Suero, Sebastián; Leicht, Anthony S.
The intensity of sports training is key to many positive consequences. This study aimed to know how motivation, self-perceived physical fitness, and self-perceived performance correlate with the intensity that young sports people showed in a session. The sample consisted of 79 athletes with ages between 10 and 16. After the right procedure (bioethical) sports people filled out a short questionnaire about their current perceived motivation, and they trained with an inertial device and heart rate monitor, placed on their body, to measure external (Player Load per minute) and internal (heart rate) intensity. They also answered another scale about their contextual motivation, perception of their performance and perception of their physical fitness. The results showed a relationship between both contextual intrinsic and identified motivation with athletes' external intensity, which also correlated with, self-perceived physical fitness and self-perceived performance. Self-perceived physical fitness was 49% predictive of Player Load per minute (r = 0.71; r2 = 0.49; Cohen’s f2 = 0.96, large; RMSE = 0.19; F(1,77) = 76.7; p < 0.001). Coaches can influence athletes' motivation to improve external intensity in sports training and their performance. ---------------------------------------------------------------------------------------------------------
Efectos de una intervención motivacional en jugadoras de baloncesto adolescentes
(Universidad de Extremadura; Federación Extremeña de Balonmano, 2025) Rebollo Infante, M. Reyes; Almagro Torres, Bartolomé Jesús; Rebollo González, José Antonio
El objetivo de este estudio fue analizar el efecto de una intervención para aumentar la satisfacción de las necesidades psicológicas básicas, la motivación autónoma, el rendimiento percibido y la intención de seguir practicando baloncesto en jugadoras infantiles. Para ello, se llevó a cabo un diseño cuasi-experimental pre-post con grupo control y grupo experimental, en el que se administró un cuestionario para evaluar distintas variables motivacionales (apoyo a la autonomía, satisfacción de las necesidades psicológicas básicas, tipo de motivación, rendimiento percibido e intención de seguir siendo físicamente activas) a 17 jugadoras con edades entre 12 y 13 años. En el grupo experimental (n = 8) la entrenadora usó un clima de apoyo a la autonomía, mientras que en el grupo control (n = 9) no hubo manipulación. La intervención abarcó un total de 5 meses (con 3 sesiones por semana de 90 minutos). Los cuestionarios se administraron antes de comenzar la intervención y al finalizar. Los resultados mostraron un incremento significativo en el grupo experimental en la percepción de apoyo a la autonomía y en la satisfacción de la necesidad psicológica básica de autonomía. ---------------------------------------------------------------------------------------------------------
The European universities initiative through the lens oforganisational actorhood: key transformations, challenges,and opportunities for universities of applied sciences andtraditional research universities
(Springer, 2026) Aceytuno Pérez, María Teresa
The European Universities Initiative (EUI) seeks to drive the transformation of participating institutions by promoting shared governance, challenge-based learning, socially impactful research, and stakeholder engagement. These aspects reflect broader trends in the transformation of higher education institutions, as discussed in the literature on organisational actorhood. From this perspective, we theoretically identify five key transformations implied by the EUI. Using an exploratory qualitative approach, we conducted expert interviews at four traditional research universities and four universities of applied sciences (UAS) to examine how alliance members navigate these key transformations. Our findings indicate that the EUI, through its impact agenda, is not the primary driver of organisational change in higher education institutions but rather acts as a facilitator of institutional reorganisation processes already underway—particularly in the case of UAS. Furthermore, we find that the EUI exerts its most transformative influence in two core areas: the emphasis on the European dimension of university alliances and the implementation of shared governance structures. These aspects are not captured by general transformational trends in higher education, thereby highlighting the EUI’s distinctive contribution to institutional development.

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