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Resolution of a positioning system with signal conditioning, based on a PSD optical sensor. Influence of system noise
No full textThis paper presents an analysis of the influence of electronic noise from sensors and electronic conditioning circuits on the resolution of measurement in a system based on a PSD (Position Sensitive Device) optical sensor. In a previous study, the authors proposed the design of signal conditioning circuits for optical sensors, which generally supply currents of tens of nA that must be suitably managed before the analogue-to-digital conversion process (total gain close to 20M). The present work comprises an analysis of resolution influenced by the noise of the proposed circuit, considering different choices for retrieving the desired information and taking into account the equivalent noise bandwidth (ENBW) used in each one. Shot noise, thermal noise and flicker noise have been considered for the different stages, as well as how next stages amplified noise of previous ones. Once the global expression of noise and its influence on resolution have been obtained, sensitivity from different parameters and the result of resolution were calculated and discussed. Some of the main results of this work indicate that the resolution on the sensor surface, depending on the method of information retrieval, is between 3 and
. This value translated to resolution in space, at a distance of 3.5 m and with a lens on the sensor of focal f=8 mm is from 1.3 to 5.2 mm.Junta de Comunidades de Castilla-La Manch
Pre-service teachers as agents of educational change via the practicum
No full textThere is still an approach to the Practicum in which pre-service teachers are still seen as trainees who cannot contribute to the experienced practice of in-service teachers. The aim of this study was to find out, from the point of view of in-service teachers, university practicum tutors and pre-service teachers themselves, whether the latter doing their last Practicum can contribute to school improvement from an inclusive perspective and, if so, in what aspects of improvement this influence is produced. A qualitative comprehensive-descriptive study was carried out during two school years with the participation of 14 in-service teachers from 2 different schools and 10 pre-service teachers who were participating in the last Practicum, as well as 2 university tutors. Results show that pre-service can play a relevant role in school improvement, especially in classroom organisation, in teacher?s professional development and, in children?s learning. Reflections on teacher training programmes are provided.Financiado por la UE a través del FEDER y por la JCCM a través de INNOCA
Exploring the role of Industry 4.0 capabilities in managing supply base complexity and enhancing supply chain agility
Full text linkGrounded in Organizational Information-Processing Theory, this study aims to explore the interrelationship between Industry 4.0 (I4.0) capabilities, supply base complexity, and supply chain agility. Data were collected from 338 Spanish focal companies. Analysis was conducted using cluster analysis and analysis of variance. Results reveal that I4.0 exploration, I4.0 exploitation, and horizontal complexity, are positively associated with supply chain agility, while delivery complexity is negatively associated. However, when horizontal complexity is low or delivery complexity is high, companies with greater I4.0 exploration and exploitation capabilities achieve significantly higher supply chain agility than those with lower I4.0 exploration and exploitation capability levels. Managers can enhance supply chain agility by leveraging I4.0 capabilities, particularly in environments with low horizontal complexity or high delivery complexity. The findings advance our understanding of how supply base complexity interacts with I4.0 capabilities to influence supply chain agility and highlight complexity's role as a double-edged sword
Facilitation of underplanted broadleaf trees by pine canopy under Mediterranean conditions depends on thinning intensity and type, not on species drought tolerance
No full text11 p.Planted forests in dry Mediterranean regions are increasingly threatened by extreme climatic events, making adaptive management strategies such as thinning and underplanting essential. To apply these restoration practices at large scales, it is necessary to understand how different tree species respond to varying thinning intensities. This study evaluated the performance of seedlings from four late-successional, resprouting Mediterranean broadleaf species ?Acer monspessulanum L., Quercus pyrenaica Willd Sorbus torminalis (L.) Crantz, and the evergreen Quercus ilex L. subsp. ballota (Desf.) Samp? underplanted along a canopy openness gradient created by thinning treatments in a 50-year-old Pinus pinaster plantation. Four thinning treatments were compared: no thinning (control), moderate thinning from below (20% basal area reduction), heavy thinning from below (35%), and heavy thinning from above (35%), leaving 28.7, 24.9 and 23.2?m2·ha?1 residual basal area, respectively. Thinning significantly increased light availability, throughfall, and soil moisture, with most improvements occurring under moderate thinning. Soil water availability increased at deeper soil layers in all thinned stands, while shallow soil moisture improved mainly under moderate thinning. After five years, seedling survival was high (>80%) across all species and generally increased with greater canopy openness. Quercus pyrenaica and Q. ilex showed the strongest positive response in survival to increased canopy opening, whereas A. monspessulanum and S. torminalis were less affected, likely due to differences in functional traits. Seedling growth was also enhanced by thinning, reaching maximum rates under moderate thinning, with S. torminalis exhibiting the highest growth and A. monspessulanum the lowest. Improved seedling performance under thinning was associated with reduced summer water stress and higher photochemical efficiency during dry periods. Overall, the study demonstrates that moderate thinning creates optimal environmental conditions for the facilitation of underplanted seedlings and provides guidelines for promoting structural and species diversification in Mediterranean pine plantations.Ministero de Ciencia e InnovaciónFondo Europeo de Desarrollo Regional (FEDER)Agencia Estatal de Investigació
Estudio de sistemas ópticos inalámbricos de comunicación en canales con turbulencias
Full text linkEl presente proyecto tiene como objetivo estudiar el rendimiento de ciertos sistemas de comunicación óptica inalámbrica cuando la señal se transmite a través de un canal afectado por turbulencia atmosférica. Para llevar a cabo este análisis, se ha modelado el canal mediante las distribuciones Gamma-Gamma y Weibull, y se han evaluado métricas clave como la tasa de error de bit (BER) y la relación señal a ruido (SNR) bajo distintas condiciones del canal.
Asimismo, se ha estudiado una estrategia de mitigación basada en la codificación de canal Reed-Solomon combinada con permutación, analizando su eficacia frente a las ráfagas de error introducidas por la turbulencia. El análisis de los resultados obtenidos permite concluir que esta técnica mejora significativamente la robustez del sistema, especialmente en escenarios de turbulencia moderada y fuerte, donde la aparición de errores correlados es más pronunciada.The present project aims to analyze the performance of certain free-space optical communication systems when the transmitted signal propagates through a channel affected by atmospheric turbulence. To carry out this study, the channel has been modeled using the Gamma-Gamma and Weibull distributions, and key performance metrics such as the bit error rate (BER) and the signal-to-noise-ratio (SNR) have been evaluated under different channel conditions.
Furthermore, a mitigation strategy based on Reed-Solomon channel coding combined with interleaving has been investigated, assessing its effectiveness against the burst errors introduced by turbulence. The analysis of the obtained results allows us to conclude that this technique significantly improves system robustness, particularly in scenarios with moderate and strong turbulence, where the occurrence of correlated errors is more pronounced.Grado en Ingeniería en Sistemas de Telecomunicació
Gobernanza de los recursos naturales. Cadena global de valor del cacao en Ecuador
Full text linkThis research shows the peculiarities of the cocoa Global Value Chain (GVC) in Ecuador. The first is the predominance of “fine aromatic cocoa” type (81 percent of its production in 2021). The second is the difference between the fine aromatic cocoa value chain structure and the conventional one: it is shorter, an important share of the value is generated locally because both production and processing are suitable for small-scale units which invest less capital and more labor, and there is a continuous exchange of information between the links and the buyers, to secure the supply and quality of the specialty product. Using the methodolo-gy “Spatially Explicit Information on Production to Consumption Systems” (SEI-PCS), which connects exporters, importers and destination countries, it is established that: in the year 2022, although the representations of companies such as Cargill and Barry Callebaut were among the main exporters, Ecuadorian domestic traders predominate (which is the third peculiarity); among the importing companies are the two previous ones in addition to Olam and Guan Chong. The main destinations for Ecuadorian cocoa are the European Union, Malaysia, the United States, and Indonesia. The Ecuadorian extractivist model requires governance of natural resources (such as cocoa, bananas and oil) that goes beyond the role of countries, supranational institutions, and other international organizations in the governance of GVCs, a role in which they have not succeeded in managing the negative externalities that harm the population and the environmentEsta investigación muestra las peculiaridades en la Cadena Global de Valor (CGV) del cacao en Ecuador. La primera, el predominio del cacao tipo “cacao fino de aroma” (81 por ciento de su producción en 2021). La segunda, la diferencia entre la estructura de la cadena de valor del cacao fino de aroma y la convencional: es más corta, una parte importante del valor se genera localmente porque tanto la producción como el procesamiento son adecuados para las unidades de pequeña escala que invierten, y hay un intercambio continuo de información entre los eslabones y los compradores, para asegurar el suministro y la calidad del producto especializado. Utilizando la metodología “Información Espacial-mente Explícita sobre Sistemas de Producción a Consumo” (SEI-PCS), que conecta a exportadores, importadores y países de destino se establece que: en el año 2022 si bien las representaciones de empresas como Cargill y Barry Callebaut se encontraban entre las principales exportadoras, los comerciantes ecuatorianos domésticos predominan (lo cual constituye la tercera peculiaridad); entre las empresas importadoras están las dos anteriores además de Olam y Guan Chong. Los principales destinos del cacao ecuatoriano son la Unión Europea, Malasia, Estados Unidos e Indonesia. El modelo extractivista ecuatoriano requiere una gobernanza de los recursos naturales que va más allá del papel de los países, las instituciones supranacionales y otras organizaciones internacionales en la gobernanza de las CGV, papel en el que no han tenido éxito gestionando las externalidades negativas que perjudican a la población y al ambiente
Ethics, Transparency, and Consumer Trust in AI-Enabled Pricing: Implications for Sustainable Technology Entrepreneurship and Economic Policy
Full text linkAI-driven dynamic pricing has evolved from an optimisation technique into a core infrastructure of the digital economy, such as the European Union Artificial Intelligence Act and global guidelines for trustworthy AI move towards implementation, questions of fairness, transparency, and consumer trust in algorithmic pricing have become urgent for firms, regulators, and entrepreneurial ventures alike. Start-ups and scale-ups are often at the frontier of deploying these systems as sustainable technology for resource-efficient demand management and revenue resilience, yet their dependence on legitimacy makes them particularly exposed to ethical, reputational, and market-acceptance failures. Despite the rapid growth of research on AI ethics, the specific intersection between algorithmic design, normative imperatives, and consumer-centric outcomes remains conceptually fragmented and insufficiently mapped. This study provides a bibliometric mapping of the emerging ethical agenda in AI-driven dynamic pricing at the interface of entrepreneurship, economics, and sustainable technology. A dataset of 38 peer-reviewed articles (2019?2025) was retrieved from Scopus using a targeted search combining dynamic pricing, Artificial Intelligence, and ethics/transparency/consumer trust. Using VOSviewer and Biblioshiny, the analysis integrates performance indicators, keyword co-occurrence, co-citation structure, and thematic evolution. The findings reveal a clear post-2022 shift from optimisation-centric work towards a more integrated discourse in which fairness, transparency, and trust become structurally central. Two dominant clusters emerge, pricing mechanisms with distributive implications and AI-enabled methodologies, while recent literature increasingly links technical design to consumer protection and economic governance, echoing policy developments associated with the European Union Artificial Intelligence Act and debates on circular economy-compatible market practices
Epidemiology of anterior cruciate ligament injuries in the top 5 european football (soccer) leagues
Full text link9 p.Background: The anterior cruciate ligament (ACL) is one of the most frequently injured structures in different sports, particularly football (soccer). Numerous studies have investigated the mechanisms and risk factors leading to ACL ruptures in this sport; however, most analyses have focused on individual leagues. Hypothesis: It was hypothesized that pooling data from different football leagues would show that (1) most ACL ruptures occur in noncontact situations, predominantly during the defensive phase and within the initial minutes of play; (2) the number and incidence rate of injuries differ significantly across leagues; and (3) the number of injuries correlates with the team market value. Study design: Descriptive epidemiology study. Methods: An online database was accessed to collect data on ACL ruptures and player characteristics in the top 5 European football leagues between the 2018-2019 and 2023-2024 seasons. Player age, player position, moment of injury during the season and during the match (if applicable), and team market value were initially collected. Then, the video of the moment of injury of those players injured during official matches was searched to classify the injury mechanism. Results: A total of 272 ACL ruptures were identified, 44.5% involving defenders. Most occurred within the first 15 minutes of play. The mean age of injured players was 25.8 ± 3.9 years. Among the 135 injuries for which video analysis was available, 84 (62.2%) occurred during defensive actions, 66 (48.9%) were classified as noncontact injuries, and 35 (33.3%) happened while pressing an opponent. Differences in the number of injuries (P = .066) and injury rate (P = .225) between leagues, as well as the correlation between team market value and number of injuries (P = .922), were not statistically significant. Conclusion: Most ACL ruptures occurred through noncontact mechanisms, typically during defensive actions, particularly while pressing an opponent. Most injuries affected defenders and took place within the first minutes of play, with a mean player age of 25.8 years. No significant differences were found in the number or rate of injuries between leagues, nor was any correlation observed between team market value and the number of injuries
Dammed ecologies, “Hydro-irrealism,”and aesthetic slowness in Betzabé García’s “Los reyes del pueblo que no existe” (2015)
No full textThis article discusses Betzabé García’s Los reyes del pueblo que no existe(Kings of Nowhere, 2015), a Mexican documentary that tackles the community-scale experiences of socio-ecological degradation, land clearing and mass displacement produced by the damming of a regional river for neoliberal hydro-development. Although the documentary primarily adheres to the defining realist gestures and formal austerity of observational and “slow cinema”idioms to capture everyday life in a flood-stricken rural landscape, as this article explores, the use of a surreal and spectral visual grammar in certain sequences seems to mediate the radical estrangement that saturates social reality in the zones of sacrifice and submergence wrought by extractive capital. Building on Warwick Research Collective’s world-ecological examination of how “irrealist aesthetics”correspond to the experience of extreme and abrupt restructuring of socio-ecological relations engendered by capitalism’s extractive operations, this article suggests that the unearthly and ghostly atmosphere conveyed through the film’s enigmatic mise-en-scène attends to the unfathomable changes to agrarian realities produced by the infrastructures of hydro-extraction, as well as to the brutal dynamics of dispossession and plunder that underpin them. Thus, reading Garcı́a’s documentary as a work that evinces what Sharae Deckard calls the “aesthetics of hydro-irrealism,”this article argues that the film fosters a critical view of the bewildering yet not immediately perceptible extractive and terror-inflicting mechanisms that structure the region’s socio-ecological rupture, attuning viewers not only to the protracted and concealed violences fostered by hydro-infrastructural development, but also to the oft-invisibilisedforms in which local communities respond to the world-destroying schemes of neoliberal extractivism.El presente artículo ofrece una discusión de Los reyes de pueblo que no existe(2015) de Betzabé García, un documental mexicano que aborda las experiencias localizadas de degradación socio-ecológica, desterritorialización y desplazamiento forzado masivo producido por la implementación de un megaproyecto hidráulico. Aunque el filme se adhiere predominantemente a los gestos característicos y austeridad formal del documental observacional y el “cine lento” para registrar la vida diaria en un territorio rural afectado por la construcción de una represa, como se explora en este artículo, el uso de una gramática visual surreal y espectral en ciertas secuencias parece mediar el radical extrañamiento que satura la realidad social de las zonas de sacrificio y afectación creadas por el capital extractivo. Basado en las discusiones del Warwick Research Collective sobre estéticas “irrealistas” y su correspondencia con las experiencias de extrema y abrupta reorganización de las relaciones socio-ecológicas impulsada por las operaciones extractivas del capitalismo, el artículo sugiere que la atmósfera espectral evocada a través de la enigmática puesta en escena del documental apunta a la incomprensible y drástica desintegración de las realidades agrarias producida por las infraestructuras del extractivismo hídrico, así como a las brutales dinámicas de desposesión y saqueo que las apuntalan. Por lo tanto, leyendo el documental como una obra que exhibe rasgos de lo que Sharae Deckard define como “estéticas hidro-irrealistas,” el artículo argumenta que el filme promueve una visión crítica de los desconcertantes, no inmediatamente perceptibles mecanismos de terror y extracción que estructuran la fragmentación socio-ecológica del territorio, guiando la mirada de los espectadores no sólo hacia las violencias lentas y ocultas del desarrollo hidráulico, sino, además, a las formas usualmente invisibilizadas en las que las comunidades locales responden a la megaproyectos de destrucción del extractivismo neoliberal
Visible-light mediated functionalization in Phe-containing peptides upon a debenzylative amination process
No full text7 p.An efficient protocol for the modification of phenylalanine-containing peptides is developed. The tandem debenzylation- amination process in N-terminal phenylalanine short peptides with N-iodoimides proceeds under visible-light irradiation and metal-free conditions. This method broadens the available chemical toolbox for the modification of Phe and allows the incorporation of N-containing heterocycles into peptide settings.Ministerio de Ciencia, Innovación y UniversidadesInstituto de Salud Carlos IIIUnión EuropeaGobierno VascoUniversidad de Alcal