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The current state of decline of elasmobranch stocks is fuelled by overfishing and a lack of ecological and biological knowledge on many of the exploited species. Several of these sharks and rays species have shown complex behaviours and sociality that influence their distribution and ecology, both determinant factors for their management. The present work focuses on the undulate ray (Raja undulata), a commercially important skate classified as endangered in 2009 by the IUCN. In NW Spain (Galicia), its population and genetic structure – as well as basic biological and ecological knowledge – remains unknown, while available abundance indexes have revealed a decreasing trend in the last years. We used genetic and acoustic telemetry tools to assess the genetic structure, spatial distribution, and the interaction of both in a dense aggregation of undulate rays located within the Cíes Islands MPA. For this, 108 specimens were characterized using eight microsatellite markers that revealed a highly connected genetic network, with almost all its individuals genetically related through at least one first-order relationship. While previous studies had demonstrated the patchy distribution of the undulate ray, this is the first work addressing the genetic structure of these ‘patches’. The species’ local population aggregates seasonally, and skates were found to have up to 10-11 direct relatives within the aggregation area. Furthermore, telemetry data from the 85 tagged skates revealed that bigger females use less space in common between them than their smaller counterparts, while bigger males were found to do the opposite. Our results demonstrate how kinship is likely to be influencing the distribution of this elasmobranch species, either by means of genetic relatedness or familiarity, and lay the foundation for the long-term monitoring, conservation and future management of the species.

La agricultura urbana (AU) es un fenómeno complejo del cual pocas veces se conoce su geografía y que generalmente opera con huertos aislados, situaciones que dificultan la planificación estratégica de acciones de mejora. El objetivo del presente estudio se centró en mapear las iniciativas de huertos urbanos y analizar su distribución geográfica en el municipio de Xalapa (Veracruz), prototipo de la AU en México. La metodología toma como punto de partida el mapeo colaborativo mediante una plataforma de recolección de datos cartografiables (Ushahidi), que fueron validados, curados y manejados para su análisis en Quantum Geographic Information System (QGIS). Los resultados muestran el registro de 160 huertos para la Zona Metropolitana de Xalapa (ZMX), los cuales tienen asociada una comunidad aproximada de 3.263 personas y ocupan una superficie de 205.506 m2. La distribución espacial de la AU en el municipio tiende al agrupamiento y se concentró principalmente en la mancha intraurbana. La mayor parte de los huertos urbanos están ubicados en la ciudad de Xalapa-Enríquez, especialmente en colonias con baja y media marginación, sugiriendo que los huertos no están vinculados mayormente a la autosuficiencia alimentaria, sino a causas socioecológicas como reconstrucción del tejido social y la defensa del territorio. La propuesta metodológica puede ser replicable para aproximarnos al fenómeno de la AU en otras ciudades, así como para generar cartografías interactivas para la articulación de redes de colaboración y políticas públicas, aspectos cruciales para la sustentabilidad de la agricultura urbana., Urban agriculture (UA) is a complex phenomenon with a largely unknown geography and which generally operates with isolated orchards, making the strategic planning of improvement actions difficult. The objective of this study is focused on mapping urban garden initiatives and analyzing their geographical distribution in the municipality of Xalapa (Veracruz), a prototype of UA in Mexico. The methodology begins with collaborative mapping through a mappable data collection platform (Ushahidi), which was validated, curated and managed for analysis in QGIS. The results show the registration of 160 vegetable gardens for the Metropolitan Zone of Xalapa (ZMX), which have an associated community of approximately 3.263 people and occupy an area of 205.506 m2. The spatial distribution of UA in the municipality tends to cluster and is mainly concentrated in the intra-urban area. Most of the urban gardens are located in the city of Xalapa-Enríquez, especially in neighborhoods with low and medium marginalization, suggesting that the vegetable gardens are not linked mainly to food self-sufficiency, but to socio-ecological causes such as the reconstruction of the social fabric and defense of the territory. The methodological proposal can be replicated to address the UA phenomenon in other cities, and to generate interactive cartography for the articulation of collaboration networks and public policies, crucial aspects for the sustainability of urban agriculture.

Non-competitive cooperative motor games hold the potential to educate gender equity from a relational perspective. These motor games present educational relational challenges where different genders interact for mutual benefit. Such interactions generate emotional well-being, enhance socio-affective relationships, and promote feminized motor conducts that potentially perform gender hegemonies and reduce gender stereotypes. This study, grounded in the ethics of care and motor praxeology, explored the effects of non-competitive cooperative motor games on group and cross-gender socio-affective rejections, gender stereotypes and emotional well-being, along with the mediation effects of these interconnected variables. Researchers conducted a quasi-experimental study where 11 participants (Mage = 11.16; SD = 1.35) from a summer sports camp played non-competitive cooperative motor games. The study employed sociometric questionnaires, emotional questionnaires (PANAS-C) and gender stereotype questionnaires (NATGEN). Data were analyzed using inferential and descriptive statistical techniques, social network analysis and mediation analysis. Results revealed the effectiveness of non-competitive cooperative motor games in reducing cross-gender rejections among girls, maintaining low group rejections, promoting emotional well-being and reducing gender stereotypes. Mediation analysis showed that gender stereotypes and positive emotions act as a protective barrier against group rejection. This study presents an innovative educational perspective that combines the scientific foundations of motor praxeology with the theoretical bases of the ethics of care. The research provides teachers and researchers with a practical pedagogical tool based on non-competitive cooperative motor games. These games are designed to enhance gender equity, promote emotional well-being, and reduce gender-based rejection and stereotypes., Los juegos motores cooperativos no competitivos poseen el potencial de educar la equidad de género desde una perspectiva relacional. Estos juegos motores plantean retos relacionales educativos donde los diferentes géneros interactúan en beneficio mutuo. Dichas interacciones generan bienestar emocional, potencian las relaciones socioafectivas y promueven conductas motrices feminizadas que potencialmente performan las hegemonías de género y reducen los estereotipos de género. Este estudio, fundamentado en la ética de los cuidados y la praxeología motriz, exploró los efectos de los juegos motores cooperativos no competitivos sobre los rechazos socioafectivos grupales y entre géneros, los estereotipos de género y el bienestar emocional, junto con los efectos de mediación de estas variables interconectadas. Los investigadores llevaron a cabo un estudio cuasi-experimental en el que 11 participantes (Medad = 11,16; SD = 1,35) de un campamento deportivo de verano jugaron a juegos motores cooperativos no competitivos. El estudio empleó cuestionarios sociométricos, cuestionarios emocionales (PANAS-C) y cuestionarios de estereotipos de género (NATGEN). Los datos se analizaron mediante técnicas estadísticas inferenciales y descriptivas, análisis de redes sociales y análisis de mediación. Los resultados revelaron la eficacia de los juegos motores cooperativos no competitivos para reducir los rechazos de las chicas a los chicos, mantener bajos los rechazos grupales, promover el bienestar emocional y reducir los estereotipos de género. El análisis de mediación mostró que los estereotipos de género y las emociones positivas actúan como una barrera protectora frente al rechazo grupal. Este estudio presenta una perspectiva educativa innovadora que combina los fundamentos científicos de la praxeología motriz con las bases teóricas de la ética del cuidado. La investigación proporciona a profesores e investigadores una herramienta pedagógica práctica basada en juegos motores cooperativo

The feeling of concern linked to structuring the teacher's competency profile is not new. Still, it has recently been taken into account in higher education due to its implication on the practice and quality of teaching. The purpose of the research proposal was to establish the relationship between digital competence, pedagogical practice, and reflective practice from the participation of university teachers. It was developed under a positivist paradigm, hypothetical-deductive method, quantitative approach, non-experimental-correlational design, correlational and cross-sectional type. The sample comprised 66 teachers in the Faculty of System Engineering and Computer Science and Education of a Public University of Madre de Dios, selected by non-probabilistic means for convenience. The variables, the survey, and three questionnaires were used as instruments, duly validated by experts, and were of high reliability. The results confirmed that digital competencies and pedagogical practice have a moderate relationship; therefore, greater concern is evident to innovate the educational process. In addition, a moderate relationship was found between digital competencies and reflective practice, giving an understanding that from the reflection on teaching performance, participation and concern about the improvements in their skills are evident. Finally, the very high relationship between pedagogical practice and reflective practice was confirmed; the reflection of the practice focuses on improving the educational process., El sentimiento de preocupación vinculada a la estructuración del perfil competencial del docente no es algo nuevo, sino que recientemente es tomado en cuenta en educación superior, debido a la implicancia que tiene sobre la práctica y la calidad de enseñanza. La propuesta investigativa tuvo como finalidad establecer la relación entre la competencia digital, práctica pedagógica y práctica reflexiva, desde la participación de docentes universitarios. Se desarrolló bajo un paradigma positivista, método hipotético-deductivo, enfoque cuantitativo, diseño no experimental-correlacional, tipo correlacional y de corte transversal. La muestra estuvo conformada por 66 docentes que laboran en la facultad de Ingeniería de Sistema e Informática y Educación de una Universidad Pública de Madre de Dios, seleccionados por medios no probabilísticos, por conveniencia; para medir a las variables se utilizó la encuesta y como instrumentos tres cuestionarios, debidamente validados por expertos y de alta confiabilidad. Respecto a los resultados, se confirmó que las competencias digitales y la práctica pedagógica poseen una relación moderada, por ende, se evidencia mayor preocupación para innovar el proceso educativo, además, se encontró una relación moderada de las competencias digitales con la práctica reflexiva, dando entender que a partir de la reflexión sobre el desempeño docente, se evidencia participación y preocupación sobre las mejoras de sus competencias, y finalmente se confirmó la relación muy alta entre la práctica pedagógica y práctica reflexiva, es decir, que a partir de la reflexión de la práctica se incide sobre la mejora del proceso educativo.

This article justifies the utilization and analysis of Traditional Sports Games (TSG) as an inclusive tool for gender, aiming to unveil the strategic procedures employed by students in the development of their strategic plans, as well as to enhance interpersonal coexistence through the practice of the game 'El Marro'. A 360-degree multidimensional approach, grounded in natural settings, is adopted to investigate two 'El Marro' game sessions featuring asymmetrical participation of players (24 participants; M = 19.4; SD = 1.3). Once reliable data quality indicators were achieved, descriptive, predictive (Chaid Model), and T-Patterns analyses were conducted. The findings revealed that men exhibited higher speed than women (p < .001). Furthermore, the role played by participants emerged as the primary explanatory variable in the Chaid model (p < .001). Through T-Patterns analysis, different levels of complexity in game interpretation were identified among the players. Specifically, out of the 12 players analyzed, 8 players (2 girls and 6 boys) demonstrated a complexity level of 3, while 4 boys surpassed these complexity levels. These findings suggest that the played role can serve as a tool to modulate organic variables that characterize differences between women and men. The results indicate that the roles assumed in the game 'El Marro' can be employed by educators as allies to promote the development of interpersonal relationships and foster the creation of a shared ludic micro-society between women and men., Este artículo justifica el empleo y análisis de los Juegos Deportivos Tradicionales (JDT) como una herramienta inclusiva de género con el objetivo de desvelar los procedimientos estratégicos utilizados por el alumnado en la construcción de sus planes estratégicos, así como mejorar la convivencia interpersonal a través de la práctica del juego 'El Marro'. Se adopta un enfoque multidimensional de 360º, basado en situaciones naturales, para estudiar dos partidas del juego 'El Marro', con una participación asimétrica de las/los jugadoras/es (24 participantes; M = 19.4; SD = 1.3). Una vez obtenidos indicadores fiables de calidad de los datos, se realizaron análisis descriptivos, predictivos (Modelo Chaid) y análisis de patrones temporales (T-Patterns). Los resultados mostraron que los hombres emplearon una velocidad superior a la de las mujeres (p < .001). Además, el rol jugado por los participantes se reveló como la variable explicativa principal en el modelo Chaid (p < .001). Mediante el análisis de T-Patterns, se identificaron diferentes niveles de complejidad en la interpretación del juego por parte de las/los jugadoras/es. Específicamente, de los 12 jugadores/as analizados, 8 (2 chicas y 6 chicos) revelaron un nivel de complejidad 3, mientras que 4 chicos superaron estos niveles de complejidad. Estos hallazgos sugieren que el rol jugado puede ser una herramienta para modular variables orgánicas que caracterizan las diferencias entre mujeres y hombres. Los resultados indican que los roles desempeñados en el juego 'El Marro' pueden ser utilizados por los docentes como aliados para fomentar la educación de las relaciones interpersonales y construir una microsociedad lúdica compartida entre mujeres y hombres.

The scoring system based on accumulation-decumulation involves a transfer in the teams scoring. It is confirmed in the triad game studied the ambivalent effect of motor situations and how it reduces the differences between the teams that revert to the scoring system. The analysis was carried out through the role frequencies, performance rate, throughout three moments during the development of the game; in addition, a T-Patterns analysis was applied to find out the differences through the T-Patterns. A parallel reflection was established about the social message and the pedagogical repercussion which emanates from the studied scoring system., El sistema de puntuación basado en la acumulación-desacumulación comporta un trasiego en la puntuación de los equipos. En el juego de tríada estudiado se confirma el efecto ambivalente de las situaciones motrices y cómo reduce las diferencias entre los equipos que revierten en el marcador. El análisis se realiza a través de la frecuencia de roles, tasa de actuación, y todo ello en tres momentos del desarrollo del juego; además, se aplica una prueba T-Patterns, para conocer las diferencias a través de los patrones temporales. Se establece una reflexión paralela acerca del mensaje social y la repercusión pedagógica que emana del sistema de puntuación estudiado.

This communication proves that the analysis of the scattering by a mirror-symmetric multilayered periodic structure (MPS) can be replaced by the analysis of the scattering by two semi-structures with half the size in which the symmetry plane behaves either as a perfect magnetic conductor (PMC) or as a perfect electric conductor (PEC). The proof is based on the reflection properties of the electric and magnetic fields through PMCs and PECs, and it is valid for arbitrary oblique incidence. As an application of this concept, the spectral-domain method of moments (SD-MoM) is reformulated to deal with MPSs limited by PMCs and PECs, and it is used in the design of a mirror-symmetric multilayered linear polarization (LP)-to-circular polarization (CP) converter. The results obtained with SD-MoM are validated by comparison with commercial software CST. Numerical simulations show that the CPU time required by both SD-MoM and CST in the analysis of half the LP-to-CP converter limited by PMC and PEC is between 30% and 42% smaller than that required by the analysis of the complete LP-to-CP converter, which shows the numerical advantage gained in exploiting the symmetry when it is present.

The biodegradation of polyethylene glycol of molecular weight 400 - PEG 400 was evaluated with the consortium Pseudomonas sp. and Rhizobium trifolii in Batch reactors. To determine the optimal operating conditions of the reactor, a medium with minimum essential salts supplemented with CSMEP peptone was prepared; In these media, the behavior of the consortium was estimated with temperature conditions between 15-37°C, pH in a range of 5-9 and PEG 400 concentration of .1-2%. With the results obtained in these previous tests, three Batch - BK reactors were assembled. 14 samples of the contents of each one of the reactors were analyzed during 20 days to measure the biodegradation of PEG 400 using chemical oxygen demand - COD in a closed digestion system. A decrease of up to 98.5% of the polyether was obtained, which showed that the symbiosis was effective to achieve an important removal of the contaminant., Se evaluó la biodegradación de polietilenglicol de peso molecular 400 - PEG 400 con el consorcio Pseudomonas sp. y Rhizobium trifolii en reactores en Batch; para determinar las condiciones óptimas de operación del reactor se preparó medio con sales mínimas esenciales suplementado con peptonaCSMEP; en estos medios se estimó el comportamiento del consorcio con condiciones de temperatura entre 15-37°C, pH en un rango de 5-9 y concentración de PEG 400 del .1-2%. Con los resultados obtenidos en estos ensayos previos se ensamblaron tres reactores en Batch - BK. Se analizaron 14 muestras del contenido de cada uno de los reactores durante 20 días para medir la biodegradación del PEG 400 usando demanda química de oxígeno - DQO en sistema de digestión cerrado. Se obtuvo una disminución de hasta el 98.5% del poliéter, lo que mostró que la simbiosis fue efectiva para alcanzar una remoción importante del contaminante.

Geodesic-lenses are a compelling alternative to traditional planar dielectric lens antennas, as they are low loss and can be manufactured with a simple mechanical design. However, a general approach for the design and analysis of more advanced geodesic-lens antennas has been elusive, limiting the available tools to rotationally symmetric surfaces. In this article, we present a fast and efficient implementation built on geometrical optics and scalar diffraction theory. A numerical calculation of the shortest ray path (geodesic) using an open-source library helps quantify the phase of the electric field in the lens aperture, while the amplitude is evaluated by applying ray-tube power conservation theory. The Kirchhoff-Fresnel diffraction formula is then employed to compute the far field of the lens antenna. This approach is validated by comparing the radiation patterns of a transversely compressed geodesic Luneburg lens (elliptical base instead of circular) with the ones computed using commercial full-wave simulators, demonstrating a substantial reduction in computational resources. The proposed method is then used in combination with an optimization procedure to study possible compact alternatives of the geodesic Luneburg lens with size reduction in both the transverse and vertical directions.

Vacuum fluctuation-induced interactions between macroscopic metallic objects result in an attractive force between them, a phenomenon known as the Casimir effect. This force is the result of both plasmonic and photonic modes. For very thin films, field penetration through the films will modify the allowed modes. Here, we theoretically investigate the Casimir interaction between ultrathin films from the perspective of force distribution over real frequencies for the first time. Pronounced repulsive contributions to the force are found due to the highly confined and nearly dispersion-free epsilon-near-zero (ENZ) modes that only exist in ultrathin films. These contributions persistently occur around the ENZ frequency of the film irrespective of the interfilm separation. We further associate the ENZ modes with a striking thickness dependence of a proposed figure of merit (FOM) for conductive thin films, suggesting that the motion of objects induced by Casimir interactions is boosted for deeply nanoscale sizes. Our results shed light on the correlation between special electromagnetic modes and the vacuum fluctuation-induced force as well as the resulting mechanical properties of ultrathin ENZ materials, which may create new opportunities for engineering the motion of ultrasmall objects in nanomechanical systems.