Review on phase change material emulsions for advanced thermal management: design, characterization and thermal performance

Interest in phase change material emulsions (PCMEs) as advanced thermal storage and heat transfer media is growing and this is leading to an increase in the number of articles on the subject. This review attempts to summarize previous research on formulation, thermophysical, rheological, hydrodynamics and heat transfer properties of PCMEs in order to provide an insight of the advantages and challenges of these novel materials. Specific attention is paid to experimental investigations on emulsion stability during storage time, but also under freeze-thaw cycling, shear mechanical stresses or other operational conditions in which materials must work in thermal facilities. Main outcome of phase change characteristics is discussed, analyzing strategies proposed in the literature to address undesirable sub-cooling phenomena. The influence of droplet size, surfactant type or dispersed phase concentration on other thermophysical and rheological properties is also revised in order to further understand how those parameters affect storage capacity and thermo-hydrodynamic performance of PCMEs. Finally, the article provides an overview of the potential of phase change material emulsions for efficient thermal management and promoting the use of renewables in different industrial fields.Consiglio Nazionale delle Ricerche (Italia) | Ref. SOE2/P1/P0823Ministerio de Ciencia e Innovació

A quantitative binding study of fibrinogen and human serum albumin to metal oxide nanoparticles by surface plasmon resonance

The interaction of plasma proteins with metal oxide nanoparticles (NPs) is important due to the potential biomedical application of these NPs. In this study, new approaches were applied to measure quantitatively the kinetics and affinities of fibrinogen and human serum albumin (HSA) for TiO2, CeO2, Al2O3 and ZnO NPs immobilized on a sensor chip. Real-time surface plasmon resonance (SPR) measurements showed that fibrinogen interacted with TiO2 and CeO2 NPs with high affinity (135 and 40 pM, respectively) and to Al2O3 NPs with moderate affinity (15 nM). The data fitted well to the Langmuir model describing a 1:1 interaction. In contrast, HSA interacted with TiO2, CeO2 and Al2O3 NPs with lower affinity (80 nM, 37 nM and 2 µM, respectively) with the data fitting better to the conformational change model. TiO2 and CeO2 NPs had fast association rate constants with fibrinogen (1×106 M−1 s−1) and Al2O3 NPs had a slower association rate constant (1×104 M−1 s−1). By contrast, HSA had markedly slower association rate constants (1×103–1×104 M−1 s−1). The binding of the proteins was reversible, thus allowing the rapid capture of data for replicates. The occurrence of matrix effects was evaluated by using surfaces with different chemistries to capture the NPs, namely alginate, NeutrAvidin and bare gold. The affinity values determined for the NP–protein interactions were largely independent of the underlying surface used to capture the NPs.Xunta de Galicia | Ref. GPC2013-00

Aspiring and inspiring: the role of women in educational leadership

Purpose This study aims to delve deep into the differences observed in leadership acquisition and development between men and women and analyse the impact of certain extra-curricular activities demonstrated to influence leadership acquisition. With this evidence, this study intends to detect areas that require deeper analysis and suggest actions to redress the balance and promote a more egalitarian leadership in education in both teaching and management positions. Design/methodology/approach Accidental, as opposed to random, sampling was used via a cross-curricular study with a quasi-experimental design. The participants in this study were 335 teacher training students in Spanish universities. The Teamwork Skills Questionnaire was used to evaluate leadership and a self-assessment questionnaire to measure extracurricular activities. Findings Female students score lower in leadership skills and are engaged in fewer activities associated with successful leadership skills development. Very few students receive any training on leadership, with even fewer female than male students. Furthermore, the practice of certain extra-curricular activities can boost leadership skills. It has also been noted that these activities are carried out in different ways, depending on student gender. Originality/value This study has two points of focus: the level of leadership among education students, differentiating between male and female students, and the impact of certain extra-curricular activities carried out during the academic year, which have proven to have a considerable effect on the development of leadership skills

Comprendiendo el comportamiento de rechazo escolar en la adolescencia: perfiles de riesgo y estilo atribucional ante los resultados académicos

Adolescents who show a tendency to refuse school could also be experiencing poor motivation towards learning. The present work aimed to identify profiles of adolescents with school refusal behavior (SRB) and to examine whether these possible groups differed in academic self-attributions. Participants were 1183 Spanish students (53.7% girls) from 14 to 17 years old (M = 15.58, SD = 1.08). They answered to the Spanish versions of the School Refusal Assessment Scale-Revised (SRAS-R) and the Sydney Attribution Scale (SAS). Four SRB profiles were found by the Latent Profile Analysis technique: non-SRB, moderately high SRB, anxious SRB, and high SRB. Statistically significant differences were identified among the four groups in all the academic self-attributions examined. The anxious and high SRB profiles showed a greater tendency to attribute their academic failures to ability, while they tended to attribute their successes less to internal causes. Intervention strategies are suggested to attend these risk SRB profiles.Los adolescentes que muestran una tendencia a rechazar la escuela podrían estar experimentando también una baja motivación hacia el aprendizaje. El presente trabajo tiene como objetivo identificar perfiles de adolescentes con comportamiento de rechazo escolar (CRE) y examinar si estos posibles grupos difieren en autoatribuciones académicas. Participan 1183 estudiantes españoles (53.7% chicas) de 14 a 17 años (M = 15.58, DT = 1.08). Responden a las versiones españolas de la School Refusal Assessment Scale-Revised (SRAS-R) y la Sydney Attribution Scale (SAS). Se hallan cuatro perfiles de CRE mediante la técnica de Latent Profile Analysis: no-CRE, CRE moderadamente alto, CRE ansioso y CRE alto. Se identifican diferencias estadísticamente significativas entre los cuatro grupos en todas las autoatribuciones académicas examinadas. Los perfiles CRE ansioso y alto muestran una mayor tendencia a atribuir sus fracasos académicos a la capacidad, mientras que tienden a atribuir menos sus éxitos a causas internas. Se sugieren estrategias de intervención para atender estos perfiles de CRE de riesgo

Robotic therapy versus conventional therapy in stroke patients, a systematic review

Introducción: la terapia convencional se ha mostrado eficaz en el tratamiento de pacientes con ictus, pero enocasiones sus técnicas resultan monótonas, reduciendo la adherencia del paciente. En los u ltimos an os se handesarrollado tecnologías que proporcionan a estos pacientes elementos clave de un adecuado programa de neurorrehabilitación, tales como los sistemas robóticos para la reeducación de la marcha. El objetivo del presente trabajo es comparar los efectos de la terapia robótica y la terapia convencional en la reeducación de la marcha enpacientes con ictus. Material y método: se ha realizado una búsqueda en las bases de datos Pubmed y Medlineutilizando el término MeSH “Robotics” y las palabras clave “physical therapy modalities”, “stroke” y “gait”. Se incluyeron ensayos clínicos aleatorizados publicados los 5 últimos años en idioma castellano, inglés, francés, italiano o portugués cuya muestra fuese pacientes con ictus y cuya intervención realizase una comparación entreterapia robótica y terapia convencional. Resultados: la estrategia de búsqueda proporcionó un total de 39 resultados de los cuales fueron incluidos en esta revisión 8 ensayos clínicos aleatorizados. Los dispositivos analizados son el Lokomat, empleado en 4 de los estudios. En los estudios restantes se han empleado dispositivos talescomo Gait Exercise Assist Robot, Stride Management Assist, i-Walker y Robowalk. Conclusión: la aplicación dela terapia robótica puede ser un apoyo útil ante la rehabilitación de personas con ictus para la recuperación de lafuncionalidad en la marcha, pero no se ha demostrado una eficacia real y superior en comparación a la terapiaconvencional. Palabras clave: robótica, modalidades de Fisioterapia, ictus, marcha.Introduction: conventional therapy has been shown to be effective in treating stroke patients, but its techniques are sometimes monotonous, reducing patient adherence. In recent years, technologies have been developed that provide these patients with key elements of an adequate neurorehabilitation program, such as roboticsystems for gait reeducation. The aim of the present work is to compare the effects of robotic therapy and conventional therapy in gait reeducation in stroke patients. Material and method: a search was carried out in the Pubmed and Medline databases using the MeSH term “Robotics” and the keywords “physical therapy modalities”, “stroke” and “gait”. Randomized clinical trial, published in the last five years in Spanish, English, French, Italian or Portuguese were included whose sample consisted of stroke patients and whose intervention made a comparisonbetween robotic therapy and conventional therapy. Results: the search strategy yielded a total of 39 results of which a total of 8 randomized clinical trials were included in this review. The devices analyzed are the Lokomat, used in 4 of the studies. Devices such as Gait Exercise Assist Robot, Stride Management Assist, i-Walker, and Robowalk have been used in the remaining studies. Conclusion: the application of robotic therapy can be a useful support in the rehabilitation of people with stroke for the recovery of functionality while walking, but no real and superiorefficacy compared to conventional therapy has been demonstrated

Can vermicomposting be used to process hyperaccumulator biomass in nickel agromining?

Hyperaccumulator plants are a botanical curiosity that have allowed the development of agromining of metals, with a special focus on nickel. In nickel agromining, this element is recovered from ashed hyperaccumulators cultivated on metal-rich soils. In order to explore bio-based approaches for the decomposition of hyperaccumulator biomass and nickel recovery that do not include burning, we performed a vermicomposting experiment using the earthworm species Eisenia andrei and the biomass of Bornmuellera emarginata (which contained almost 1% of nickel). We conducted our experiment for 12 weeks and assessed the decomposition process of the hyperaccumulator biomass, changes in earthworm number and biomass, and changes in nickel concentration and mobility. Despite the initial mortality and an increase of Ni concentration in earthworm tissues, E. andrei was able to decompose B. emarginata biomass. This process also showed a massive colonization of the biomass by a fungus during the first weeks of the assay. Our results indicate that the vermicomposted hyperaccumulator biomass had a higher nickel concentration than the starting material but the diethylenetriaminepentaacetic acid-extractable nickel decreased. At the same time, due to earthworm activity, the nickel was redistributed and diluted in the vermicompost bedding, reducing the interest of this approach for agromining, but opening the perspective of using the vermicomposted hyperaccumulator biomass as an organic amendment in nickel-deficient crops.Agencia Estatal de Investigación | Ref. PID2021-124265OB-I00Xunta de Galicia | Ref. ED431C 2022/07Agencia Estatal de Investigación | Ref. TED2021-129437B-I00Universidade de Vigo/CISU

La interpretación de los convenios para evitar la doble imposición suscritos por España

[Inicio] La globalización económica: su incidencia en el sistema de fuentes del derecho tributario 1. Consideraciones generales 1.1. Concepto de globalización En los últimos años han proliferado una serie de factores que integran el proceso conocido como «globalización económica» (1) . Dicho proceso entraña una progresiva integración de la economía nacional en la internacional, de modo que su evolución depende cada vez más del mercado exterior y no exclusivamente de la política interna (2) . Podemos definir la globalización económica atendiendo al concepto acuñado por el Fondo Monetario Internacional (en adelante, FMI), para quien «la globalización significa, en primer lugar, un proceso de creciente división internacional del trabajo y la consiguiente integración de las economías nacionales a través del comercio de bienes y servicios, la inversión externa de empresas y los flujos financieros. Y precisamente el progreso técnico, sobre todo en el ámbito de los transportes y las comunicaciones, favorece este proceso» (3) . En este punto, UCKMAR considera, en primer lugar, que a esa definición habría que añadir las diferentes formas de inversión directa e indirecta en el extranjero (constitución de filiales, sucursales, joint-ventures, etc.). Además, señala este autor que la globalización no sólo se lleva a cabo a través de operaciones internacionales, sino transnacionales, donde la fabricación de un producto tiene lugar en diversas fases productivas realizadas en países distintos (4) . De otra parte, es necesario precisar que la globalización es un fenómeno reciente; lo que no es reciente es el modelo de internacionalización. Los orígenes de la internacionalización los podemos encontrar en el siglo XI, momento en el que la República de Venecia basaba su crecimiento en el comercio con otras ciudades. [...

Evaluation of food habits and physical activity in Galician students

Introducción: la obesidad causa millones de muertes anuales. Su elevada prevalencia en niños y adolescentes de países del sur de Europa, entre ellos España, se asocia con las nuevas preferencias alimentarias y la disminución de actividad física. Objetivos: evaluar la calidad de la dieta y la práctica de actividad física en escolares gallegos para valorar la necesidad de modificar las estrategias actuales de intervención en estilos de vida. Métodos: se estudiaron 662 niños de Galicia (9-17 años). Se calculó su índice de masa corporal (IMC) como indicador de adiposidad. El patrón alimentario se evaluó con el cuestionario Kidmed y la actividad física con el PAQ-C. Se estratificó la muestra en función del IMC de acuerdo con los estándares internacionales de Cole. Los datos se analizan con el paquete SPSS. Resultados: el 56 % de los escolares están en riesgo elevado de malnutrición por exceso o necesitan mejorar su alimentación. La adherencia media al patrón alimentario mediterráneo fue baja (7,64 ± 2,28), empeorando significativamente con la edad y la adiposidad. El nivel de actividad física medio fue moderado (3,02 ± 0,74), significativamente menor en niñas y adolescentes. El 58 % mostraron un nivel bajo-moderado de actividad física. La calidad de la dieta se correlacionó positivamente con la actividad física y negativamente con el IMC. Conclusiones: los escolares gallegos presentaron un patrón alimentario y de actividad física de riesgo en relación con las recomendaciones nacionales/internacionales. Tras varios años de campañas de concienciación e intervenciones sobre estilos de vida, continúa siendo necesario mejorar la dieta y aumentar la práctica física-deportiva.Introduction: obesity causes millions of deaths each year. Its high prevalence in children and adolescents from southern European countries, including Spain, is associated with the new food preferences and decreased physical activity. Objectives: to evaluate diet quality and physical activity in Galician schoolchildren in order to assess if modifying the current intervention strategies in lifestyles is required. Methods: in the present study, 662 students from the south of Galicia were studied (9-17 years). Body mass index (BMI) was calculated as adiposity indicator. The dietary pattern was evaluated through the Kidmed test and physical activity with PAQ-C. The sample was stratified by BMI according to Cole international standards. Data were analysed with the SPPS software. Results: fifty-six per cent of children are at high risk of overnutrition or need to improve their nutrition. The average adherence to the Mediterranean diet was low (7.64 ± 2.28), worsening with age and adiposity significantly. The average level of physical activity was moderate (3.02 ± 0.74) and it was lower in girls and adolescents; 58 % showed a low-moderate level of physical activity. Quality diet was positively correlated with physical activity and negatively with BMI. Conclusions: Galician students showed a diet and physical activity risky pattern according to international/national recommendations. After several years of awareness campaigns and lifestyle interventions, improving their diet and increasing physical activity is still necessary.Instituto de Salud Carlos III | Ref. PI16/0130

New mobility technologies as incentive to location decisions: relocation strategy in the automotive industry

Purpose: The purpose of this paper is to analyze the new technologies that condition location strategy and enable the reindustrialization of European countries involved in the automotive industry. Business relocation has seen an upsurge in recent years. The development of the technologies linked to new mobility (connected, autonomous and electric vehicles) in European countries is increasing interest in relocating high value activities in origin countries to preserve high quality jobs and maintain competitive advantage. Design/methodology/approach: The paper analyzes the changes in location factors and relocation trends through qualitative research based on a multiple case study methodology of first level suppliers in the automotive industry. Findings: This study reveals the capacity technology has to reconfigure the automotive value chain and to change traditional location factors and relocation trends. The results show relevant differences between the traditional components production divisions characterized by offshoring processes, in a continuous decrease of activity and deindustrialization, and the new technologies divisions linked to new mobility with strong growth, reshoring of the high value activities, reindustrialization plans and links with research and development. For these new mobility divisions, protection of innovation to prevent the core knowledge transfer and strong collaboration with local research institutions are key in this highly technological location context. Originality/value: The research analyzes the impact of new mobility technologies on the relocation processes in the automotive industry through an original approach based on the evolution of traditional suppliers with divisions linked to new mobility.Agencia Estatal de Investigación | Ref. PID2020-116040RB-I0

Los acuerdos de los órganos administrativos colegiados

Este artículo tiene por objeto el estudio del régimen jurídico de los acuerdos de los órganos administrativos colegiados previsto en la Ley 40/2015, de Régimen Jurídico del Sector Público. Se presta especial referencia al régimen de la nulidad de los acuerdos, a las nuevas posibilidades y dudas derivadas de la incorporación de medios electrónicos, así como al quorum de asistencia y a los distintos sistemas de votaciones. Se incluye valoración crítica de las últimas novedades jurisprudenciales que zanjan viejas polémicas doctrinales en relación con la regla del quorum en primera convocatoria.This report is intended to review the legal regime of the decisions of the administrative collegiate bodies envisaged in law 40/2015, of 1 October, on the Public Sector. Special reference is given to the the nullity of proceedings, to the new possibilities and doubts arising from the incorporation of electronic media, to the quorum, and to the different voting majority rules. It includes the most recent and innovative judicial resolutions that put an end to old doctrinal controversies in relation to the rule of the quorum on first call