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Exploring the Association of Hallux Limitus with Baropodometric Gait Pattern Changes
No full textBackground: Hallux limitus (HL) is a condition marked by the restricted dorsiflexion of the first metatarsophalangeal joint, causing pain and functional limitations, especially
during the propulsive phase of walking. This restriction affects the gait, particularly in the
final phase, and impairs foot stability and support. HL is more common in adults and leads
to biomechanical and functional adaptations. The purpose of this study was to investigate
the differences in the center of pressure between subjects with hallux limitus and those
with healthy feet. Methods: A total of 80 participants (40 with bilateral HL and 40 healthy
controls) aged 18 to 64 were selected from a biomechanics center at the Universidade da
Coruña, Spain. The gait analysis focused on three key phases: initial contact, forefoot
contact, and the loading response. Data were collected using a portable baropodometric
platform and analyzed using IBM SPSS Statistics 29.0.2.0; statistical significance was set at
p < 0.05, with a 95% confidence interval. Results: The gait analysis indicated that the case
group exhibited statistically significant differences, showing lower values in the left foot
load response during the foot contact time (77.83 ± 40.17) compared to the control group
(100.87 ± 29.27) (p = 0. 010) and in the foot contact percentage (p = 0. 013) during the stance
phase (10.02 ± 5.68) compared to the control group (13.05 ± 3.60). Conclusions: Bilateral
HL causes subtle gait changes, with individuals showing greater contact time values in the
total stance phase versus the control group. Early detection may improve quality of life
and prevent complicationsThis research was funded by the Spanish Ministry of Science and Innovation through the
project PID2023-149353OB-I00Sociología, Trabajo Social y Salud Públic
Evaluation of an augmented reality tool for university studies of engineering
No full textEste trabajo presenta el desarrollo y evaluación de una herramienta de realidad aumentada (RA) para
prácticas de laboratorio en estudiantes universitarios de ingeniería. La herramienta se desarrolla utilizando la plataforma
Zappar e incluye elementos de RA en el material docente. La evaluación se realiza comparando los resultados académicos
de un grupo de estudiantes que utilizaron la herramienta con los de otro grupo que realizó la práctica de forma tradicional.
Para esto se emplean técnicas estadísticas robustas, las pruebas de la mediana y de Mann-Whitney-Wilcoxon.
Los resultados muestran que los estudiantes que utilizaron la herramienta de RA obtuvieron puntuaciones
significativamente más altas. Esto indica que la RA puede ser una herramienta efectiva para mejorar el aprendizaje en
prácticas de laboratorio, fomentando la adquisición de conocimiento y estimulando la autonomía del estudiante. La
evaluación está referida a estudiantes de ingeniería del curso 2022-23, en la Escuela Técnica Superior de Ingeniería de la
Universidad de huelvaThis paper presents the development and evaluation of an augmented reality (AR) tool for laboratory
practices in engineering students. The tool was developed using the Zappar platform and includes AR elements in the
teaching material. The evaluation was conducted by comparing the academic results of a group of students who used the
tool with those of another group who conducted the practice in a traditional way. for this, robust statistical techniques
were used, namely the median and Mann-Whitney-Wilcoxon tests.
The results show that students who used the AR tool obtained significantly higher scores. This suggests that AR can be
an effective tool for improving learning in laboratory practices, fostering knowledge acquisition and stimulating student
autonomy. The evaluation is referred to engineering students from the 2022-23 academic year, at the Escuela Técnica
Superior de Ingeniería de la Universidad de huelv
Executive functions in adolescence: A longitudinal study comparing evaluations before and after the COVID-19 pandemic
No full textThe change in the educational model derived from the COVID-19 pandemic might have an impact on cognitive development, particularly on Executive Functions (EFs). The aim of this study was to explore cognitive performance in adolescents at two time points (12 and 14 years of age), before and after the pandemic restrictions. We also analyzed possible sex differences in the results. We evaluated EFs using the Neuropsychological Battery of Executive Functions and Frontal Lobes (BANFE-2), which includes four cognitive indices corresponding to specific cognitive functions and associated prefrontal areas: Orbitofrontal Cortex (OC index -OCI-), Anterior Prefrontal Cortex (APCI), Dorsolateral Prefrontal Cortex (DCI), and Prefrontal cortex as an index of global EFs (EFI). The ANOVA conducted to compare the evaluations before and after the pandemic revealed no significant pre-post-pandemic differences in any sex and in any BANFE-2 index, except for the OCI, in which post-pandemic performance was impaired in boys (pre and post mean score = 96.61 vs. 66.53), but not in girls (pre and post mean score = 93.55 vs. 95.0). Our findings are thus compatible with the idea of a different vulnerability to change in the educational model between sexes, and they also reveal which specific EFs may have been affected during the pandemic.Psicología Clínica y Experimenta
Evaluación e integración de microrredes al sistema eléctrico
No full textEl elevado coste de la energía, la inestabilidad geopolítica y las diferentes líneas de subvención por parte de los
gobiernos han disparado el interés por la autosuficiencia energética mediante fuentes de energía renovable, tanto
en el ámbito doméstico como en el industrial. Esta creciente tendencia ha impulsado una transformación
significativa en los sistemas eléctricos tradicionales, con una integración cada vez mayor de la generación
distribuida (en inglés Distributed Generation, DG), que permite una descentralización de la producción de energía.
En este contexto, las microrredes (μredes) han surgido como una solución innovadora para integrar estas fuentes
de energía distribuidas en el sistema de potencia.
En esta tesis doctoral se aborda la problemática de flexibilizar la generación y la demanda de las μredes y se
cuantifica la mejora que éstas podrían ofrecer en los sistemas eléctricos de distribución, a los cuales están
conectadas. El objetivo principal es controlar elementos clave de las μredes, como las cargas termostáticas (TCL,
de su denominación en inglés thermostatically controlled load) y las turbinas eólicas de pequeña escala, para
mejorar su integración en los sistemas de distribución. Además, se optimizan los sistemas de distribución mediante
la consideración de nudos flexibles de generación y demanda. Dado que estos sistemas de distribución en su
mayoría tienen una configuración radial, también se propone la inserción de líneas adicionales para llegar a una
configuración radial óptima.
El estudio se organiza en cuatro bloques principales: la configuración y el control de las μredes con energía eólica
de pequeña escala, la planificación y optimización de las TCL, la evaluación de flujos de cargas en redes radiales,
y la optimización de sistemas de distribución mediante reconfiguraciones y nudos flexibles. Se presenta además la
herramienta de software OPRERES para la reconfiguración óptima de sistemas radiales, que facilita la
implementación práctica de uno de los enfoques optimizadores propuesto en la tesis.The high cost of energy, geopolitical instability, and government subsidy programs have significantly increased the
interest in energy self-sufficiency through renewable energy sources, both in domestic and industrial sectors. This
growing trend has driven a significant transformation in traditional electrical systems, with a greater integration of
distributed generation (DG), enabling the decentralization of the energy production. In this context, the microgrids
(μgrids) have emerged as an innovative solution to integrate these distributed energy sources into the power
system.
This doctoral thesis addresses the challenge of increasing the flexibility of generation and demand within μgrids
and quantifies the improvements they can offer to the distribution networks to which they are connected. The
primary objective is to control the key μgrid elements, such as thermostatically controlled loads (TCL) and smallscale
wind turbines, to enhance their integration into distribution systems. Additionally, the optimization of
distribution networks is considered by incorporating flexible generation and demand nodes. Since these distribution
systems are mostly configured radially, the insertion of additional lines is also proposed to achieve an optimal radial
configuration. The study is organized into four main sections: the configuration and control of μgrids with small-scale wind energy, the planning and optimization of TCLs, the evaluation of load flows in radial networks, and the optimization of distribution systems through reconfigurations and flexible nodes. Furthermore, the software tool OPRERES is presented for the optimal reconfiguration of radial systems, facilitating the practical implementation of one of the optimization approaches proposed in this thesis.Ingeniería Eléctrica y Térmica, de Diseño y Proyecto
A Novel Transformerless Soft-Switching Symmetrical Bipolar Power Converter: Analysis, Design, Simulation and Validation
No full textIn order to obtain acceptable efficiencies, hard-switching techniques and the converters
that implement them must operate at relatively low frequencies (tens of kilohertz),
which translate into converters of large size, weight, and volume, and therefore higher cost.
To improve these characteristics, this work introduces a new transformerless MHz-range
DC–DC converter that provides symmetrical bipolar outputs. The developed topology uses
a single grounded switch, achieves soft switching (ZVS) over a wide load range, and does
not require the use of floating or isolated controllers, reducing cost, size, and complexity.
The output voltages are self-regulated to maintain the same value, ensuring balanced
bipolar operation. A comprehensive analysis, design, sizing, simulation, implementation
and testing are provided on a 150Wprototype operating at a switching frequency of 1 MHz,
with step-up and step-down capability and implemented with GaN FET. The evaluated
configuration shows an efficiency close to 90% and high power density, making it suitable
for compact designs in a variety of applications requiring reliable power management and
high efficiency such as lighting, electric vehicles, or auxiliary power supplies.This research was funded by EPIT24 Santander–UHU: Mobility grants for international
stays for PhD students at the University of Huelva and by national funds through FCT, Fundação
para a Ciência e a Tecnologia, under project UIDB/50021/2020 (DOI:10.54499/UIDB/50021/2020).
The corresponding author is enjoying an FPU grant funded by the Spanish Ministry of Universities
for training of university teaching staff in his PhD period, grant number FPU22/03537.Ingeniería Electrónica, de Sistemas Informáticos y Automátic
Social denouncement and corruption in the work of the Frenchified Manuel José Centeno (1821)
No full textEl clero afrancesado en 1808 apostaba por la monarquía Bonaparte esperando cambios en las rígidas estructuras del Antiguo Régimen en España. El reformismo de la Ilustración francesa era la esperanza depositada en la nueva dinastía josefina, sobre todo en el orden económico, social y político del país. Con este trabajo pretendemos profundizar en el análisis de Memoria sobre los expósitos, de Manuel José Centeno, en la que trataremos de detectar las denuncias de corrupción en las instituciones de beneficencia. Este grupo de clérigos apostó por las reformas ilustradas y por la humanización del cuidado de los expósitos y huérfanos en las instituciones donde los ingresaban. La atención a las madres solteras y su seguridad fue otra de las preocupaciones manifiestas en la obra, sobre todo para evitar los abortos clandestinos y los infanticidios, tan habituales en la épocaThe Frenchified clergy in 1808 backed the Bonaparte monarchy, hoping for changes in the rigid structures of the Ancient Regime in Spain. The reformism of the French Enlightenment was the hope placed in the new Josephine dynasty, especially in the economic, social and political order of the country. The aim of this paper is to analyze Manuel José Centeno’s Memoria sobre los expósitos, in which we will try to detect the allegations of corruption in the charitable institutions. This group of clergymen supported the enlightened reforms and the humanization of the care of foundlings and orphans in the institutions where they were admitted. The care and safety of unmarried mothers was another of the concerns expressed in the work, above all to prevent clandestine abortions and infanticide, which were so common at the timeEnfermeríaHistoria, Geografía y Antropologí
Internal Cumulated Dose of Toxic Metal(loid)s in a Population Residing near Naturally Occurring Radioactive Material Waste Stacks and an Industrial Heavily Polluted Area with High Mortality Rates in Spain
No full textHuelva is a city in SW Spain with 150,000 inhabitants, located in the proximity of two heavy chemical industry complexes, the highest naturally occurring radioactive material (NORM) waste (phosphogypsum) stacks of Europe and a highly polluted estuary, with elevated cardiovascular disease and cancer mortality rates. This study analyses the association between cumulated exposure levels to 16 metal(loid)s (Al, As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Se, Tl, U, V, and Zn) measured in the toenail of a sample (n = 55 participants) of the general control population of Huelva City who were involved in the MCC-Spain study and the spatial proximity patterns to the local polluting sources. Residents of the city of Huelva have higher levels of Fe, Ni, Cr, Se, As, and Co in their toenails compared to the levels found in populations with similar characteristics living in non-polluted areas. Moreover, the highest concentrations of As, Pb, Cd, Mo, and Se were found in toenails of participants living near the NORM waste stack, while the highest Cu, Zn, and Al contents corresponded to people residing near the industrial area. The spatial distribution of most of the metal(loid)s studied appears to be mainly controlled by anthropogenic factors.This research was funded by the Andalusian
Government, ‘2018 Special Action of the Andalusian Government: Support to the Huelva Phosphogypsum
Experts Committee’; and by Huelva University local funds to support research groups
during 2018 to 2023. MCC study was funding by Carlos III Health Institute-FEDER (PI07/1160,
PS09/02078, PI12/00265, and PI17/02286), and Regional Health Ministry of Andalucía (PI-0571-2009,
PI-0306-2011, and salud201200057018tra).Química "Profesor José Carlos Vílchez Martín"Sociología, Trabajo Social y Salud Públic
Creation and implementation of 3d resources under the dua principles for the development of the executive functions in students with ASD
No full textLa propuesta de investigación aborda la creación e implementación de recursos 3D bajo los principios del
Diseño Universal para el Aprendizaje (DUA) con el objetivo de potenciar el desarrollo de funciones
ejecutivas en estudiantes con Trastorno del Espectro Autista (TEA). Se realiza una evaluación de las
funciones ejecutivas adaptada (BRIEF), implementación y evaluación tras la misma. Los resultados
preliminares indican un impacto positivo en las funciones ejecutivas tras la implementación de estos
recursos, destacando la versatilidad de la impresión 3D para la dualización del aprendizaje. La adaptabilidad
de la tecnología 3D permite personalizar materiales educativos, aprovechando las potencialidades únicas
del TEA y capitalizando las habilidades cognitivas específicas asociadas con este trastorno. La propuesta
se posiciona como una contribución significativa a la educación inclusiva, buscando no sólo suplir
deficiencias, sino también maximizar las fortalezas individuales de los estudiantes con TEA. Este enfoque
representa un paso inicial hacia un paradigma educativo más centrado en las necesidades individuales,
utilizando la impresión 3D como una herramienta clave para la dualización del aprendizaje en el contexto
del aula específica con alumnos TEAThe research proposal addresses the creation and implementation of 3D resources under the principles of
Universal Design for Learning (UDL) in order to enhance the development of executive functions in
students with Autism Spectrum Disorder (ASD). An adapted assessment of executive functions (BRIEF),
implementation and post-implementation evaluation are carried out. Preliminary results indicate a positive
impact on executive functions after the implementation of these resources, highlighting the versatility of
3D printing for the dualization of learning. The adaptability of 3D technology allows customizing
educational materials, taking advantage of the unique potentialities of ASD and capitalizing on the specific
cognitive abilities associated with this disorder. The proposal is positioned as a significant contribution to
inclusive education, seeking not only to make up for deficiencies, but also to maximize the individual
strengths of students with ASD. This approach represents an initial step towards an educational paradigm
more focused on individual needs, using 3D printing as a key tool for the dualization of learning in the
context of the specific classroom with ASD studentsPedagogí
Federalism the Brazilian way: the translation of the American system of courts and parties and the political arrangement of Campos Sales
No full textA ruptura com o modelo jurídico-político europeu é bastante conhecida quando se trata da transição monárquico-republicana brasileira. Seja em razão da acomodação dos novos discursos liberais, seja pela admiração da sua pujança econômica, os Estados Unidos são frequentemente apontados como o grande modelo da Primeira República brasileira. Ocorre que nenhuma dessas duas afirmações parece levar em consideração as transformações pelas quais os Estados Unidos, naqueles mesmos anos, também passavam. Enquanto aqui se construía uma República a partir do que parecia ser a dissolvição do centro de poder, a nação ianque também se esforçava em rearranjar o seu modelo político para dar conta da complexificação social, e principalmente do processo de industrialização pela qual passava, porém o fazia pela via contrária, pautada na necessidade de construir um centro de poder identificado com a União, e consequentemente com um aparato burocrático específico. O cientista político Stephen Skowronek desenvolveu a tese de que a expansão administrativa americana, vivida entre 1877-1920, tratou muito mais de um rearranjo do modelo político baseado no sistema de “courts and parties” (cortes e partidos), do que efetivamente uma simples resposta às necessidades da expansão capitalista. O objetivo deste texto é verificar como, para além da importação do modelo federativo americano, foi possível traduzir o modelo das “courts and parties” para a realidade brasileira. A hipótese é de que esse modelo americano influenciou duas importantes alterações que se deram no advento da República brasileira, ambas articuladas por Campos Sales: o fortalecimento dos partidos políticos através da política dos governadores de um lado, e a expansão do Judiciário de outro. Busca-se, assim, verificar em que medida o sistema das “courts and parties” americano foi traduzido à realidade brasileira pelos esforços de Campos Sales, e como ele, aqui, se materializouThe rupture with the European juridical-political model is well known when it comes to Brazil's monarchical-republican transition. Whether due to the accommodation of the new liberal discourses, or the admiration of its economic strength, the United States is often pointed to as the great model of the First Brazilian Republic. However, neither of these statements seems to take into account the transformations that the United States was also undergoing in those same years. While here a Republic was being built on the basis of what seemed to be the dissolution of the center of power, the Yankee nation was also striving to rearrange its political model to deal with the social complexification, and especially the industrialization process it was going through, but it was doing so in the opposite way, based on the need to build a center of power identified with the Union, and consequently with a specific bureaucratic apparatus. The political scientist Stephen Skowronek has developed the thesis that the American administrative expansion between 1877-1920 was much more about a rearrangement of the political model based on the “courts and parties” system than a simple response to the needs of capitalist expansion. The aim of this text is to see how, in addition to importing the American federative model, it was possible to translate the “courts and parties” model into the Brazilian reality. The hypothesis is that this American model influenced two important changes that took place at the advent of the Brazilian Republic, both articulated by Campos Sales: the strengthening of political parties through governors' politics on the one hand, and the expansion of the judiciary on the other. The aim is to see to what extent the American “courts and parties” system was translated into Brazilian reality by Campos Sales' efforts, and how it materialized hereTheodor Mommse
The current state of e-learning in university studies: bibliometric analysis and study of networks
No full textEl objetivo de este estudio es validar el uso del e-learning como metodología de aprendizaje después de la necesidad urgente generada por la pandemia. Se establece un análisis comparativo entre los estudios científicos sobre la materia y el social listening para contrastar si el aprendizaje on line sigue siendo actualmente una realidad. Se parte de analizar la actividad científica en la base de datos Wos mediante un estudio bibliométrico, del que se extrae una revisión sistémica y un metaanálisis desde el año 2019 hasta la actualidad. La declaración PRISMA centra este análisis en 50 artículos de 26 fuentes de un total de 192 autores. Posteriormente, a través de la inteligencia artificial y escucha social de redes, se conoce lo que se comenta sobre el e-learning. Al analizar y comparar los resultados científicos y sociales, se demuestra que este sistema de aprendizaje no ha seguido un desarrollo adecuado a nivel educativoThe aim of this study is to validate the use of e-learning as a learning methodology after the urgent need generated by the pandemic. A comparative analysis is carried out between scientific studies on the subject and social listening in order to contrast whether e-learning is still a reality today. It starts by analyzing the scientific activity in the Wos database through a bibliometric study, from which a systemic review and a meta-analysis are extracted from the year 2019 to the present day. The PRISMA statement focuses this analysis on 50 articles from 26 sources from a total of 192 authors. Subsequently, through artificial intelligence and social network listening, we find out what is being said about e-learning. By analyzing and comparing the scientific and social results, it is shown that this learning system has not been adequately developed on an educational level