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Factores de éxito en los equipos de trabajo de los sistemas Lean Management
No full textLos sistemas Lean se basan en una serie de principios cuya implantación incluye recursos técnicos y humanos, donde se desarrollan los equipos de trabajo multifuncionales. El objetivo principal de esta tesis es investigar las dimensiones de los equipos lean que influyen en el funcionamiento de los sistemas Lean y en los Resultados de Operaciones de las empresas. La población del estudio está formada por empresas de diferentes sectores industriales. Los datos se analizan mediante regresión lineal. Los resultados muestran que las características clave de los equipos de trabajo lean son Interdependencia, Formación al equipo, Roles de comportamiento, Toma de decisiones compartida, Liderazgo y Aprendizaje interno y externo del equipo, cuya influencia varía según el tipo de resultado considerado. Estos resultados aportan información para la dirección de los sistemas Lean en general y de los equipos de trabajo en particular.Lean systems are based on a series of principles whose implementation includes technical and human resources, where multifunctional work teams are developed. The main objective of this thesis is to investigate the dimensions of Lean work teams that influence lean and operations performance. The study population are companies from different industrial sectors. Data are analyzed using linear regression analysis. Results show that the key characteristics of work teams are interdependence, team building, behavioral roles, shared decision making, leadership, internal learning team and external learning team. The influence of those variables depends on the type of outcome considered, lean performance, quality, delivery and flexibility. No significant effect is shown when cost performance is considered. These results provide information for the management of Lean systems in general and of work teams in particular.Programa de Doctorat en Economia i Empres
Evaluación de la fisiopatología morfofuncional macular mediante imagen multimodal tras la cirugía del desprendimiento de retina
No full textCompendi d'articlesEl desprendimiento de retina con afectación macular (mácula off) es una urgencia oftalmológica que puede comprometer gravemente la visión, incluso tras una cirugía técnicamente exitosa. Esta tesis analiza y compara las dos principales técnicas quirúrgicas utilizadas (cerclaje escleral y vitrectomía vía pars plana), desde un enfoque integral, con el objetivo de mejorar la comprensión de los factores que limitan la recuperación visual óptima. Mediante el uso de tecnología avanzada de imagen como la tomografía de coherencia óptica (OCT) y la microperimetría MAIA, se analizan los resultados anatómicos, funcionales, yatrogenia inducida e impacto socioeconómico de cada técnica en el sistema sanitario. Este enfoque multidimensional pretende aportar evidencia útil para mejorar la toma de decisiones clínicas, optimizar los resultados visuales y minimizar las complicaciones, contribuyendo así al avance en el tratamiento quirúrgico del desprendimiento de retina.This doctoral thesis evaluates and compares the economic, microstructural, and functional outcomes of two surgical techniques used in the treatment of rhegmatogenous retinal detachment (RRD) of moderate complexity: pars plana vitrectomy (PPV) and scleral buckling (SB). Through a multimodal approach, three interrelated studies were conducted. The first analyses cost-utility, suggesting that both techniques are cost-effective, with SB showing a slightly more favorable economic profile. The second examines postoperative microstructural retinal changes using OCT, revealing greater photoreceptor disruption in the PPV group. The third assesses retinal function via MAIA microperimetry, showing partial visual improvement with both techniques, yet persistent functional deficits. The findings highlight that although anatomical reattachment is commonly achieved, full visual recovery remains limited, possibly due to iatrogenic or microstructural damage. This research supports a more individualized surgical approach and emphasizes the need for detailed postoperative functional and structural monitoring to optimize outcomes and healthcare sustainability in RRD management.Programa de Doctorat en Ciències Biomèdiques i Salu
Experiencias adversas en la infancia y su relación con el bienestar en jóvenes adultos: salud física y mental
No full textCompendi d'articlesLa presente tesis examina el impacto de las Experiencias Adversas en la Infancia (ACEs) sobre la salud física y mental durante la adultez emergente, considerando variables culturales y contextuales específicas de España y Latinoamérica. El Estudio 1 se centró en una muestra de jóvenes españoles, abordando el impacto de las ACEs sobre la salud física, un aspecto poco explorado en esta etapa vital. El Estudio 2 analizó la relación entre las ACEs, las estrategias de afrontamiento y la manifestación de rasgos psicopáticos y altruistas. Este estudio incorpora un enfoque innovador al considerar combinaciones específicas de ACEs en lugar de analizarlas de forma aislada. El Estudio 3 se desarrolló con una muestra de jóvenes latinoamericanos, ampliando el análisis hacia ACEs expandidas, que incluyen factores económicos y sociales relevantes en ese contexto. La tesis propone estrategias de intervención culturalmente sensibles, orientadas a la prevención y tratamiento del impacto adverso de las mismas.This thesis examines the impact of Adverse Childhood Experiences (ACEs) on physical and mental health during emerging adulthood, taking into account cultural and contextual variables specific to Spain and Latin America. Study 1 focused on a sample of Spanish young adults, addressing the impact of ACEs on physical health—an area that has received little attention during this life stage. Study 2 analysed the relationship between ACEs, coping strategies, and the manifestation of psychopathic and altruistic traits. This study adopts an innovative approach by considering specific combinations of ACEs rather than analysing them in isolation. Study 3 was conducted with a sample of Latin American young adults, expanding the analysis to include expanded ACEs, which take into account economic and social factors relevant to that context. The thesis proposes culturally sensitive intervention strategies aimed at preventing and addressing the adverse impact of such experiences.Programa de Doctorat en Estudis Internacionals de Pau, Conflictes i Desenvolupamen
Hadamard based single-pixel microscopy using sensor-less adaptive optics supported by multi-actuator adaptive lens
No full textSingle-pixel microscopy is a computational imaging approach that produce images with a bucket detector by illuminating the sample with a sequence of micro-structured light patterns. In particular, Hadamard-based single-pixel microscopy (HSPM) is a leading implementation that uses Hadamard-basis patterns typically encoded on a digital-micromirror-device (DMD). Ultimate image quality and resolution depend on accurate demagnification of the patterns onto the sample, often requiring subwavelength projection resolution. However, aberrations introduced by DMDs, which are designed for consumer displays, together with sample scattering, constrain the HSPM maximum achievable performance under practical imaging conditions. In this work, the aberrations effects on HSPM are addressed, both theoretically and experimentally, thereby enabling HSPM near-diffraction-limited operation. The use of a multi-actuator adaptive lens to correct the aberrations effect on the projected patterns in HSPM is reported. A sensor-less method is developed to achieve aberration-free HSPM, leveraging direct frequency information from the sample Hadamard spectrum in a reconstruction-free approach. The proposed method is validated by correcting not only optical system but also sample’s induced aberrations, achieving near-diffraction-limit resolution. Consolidating the presented work as a framework that could play a major role in the development of single-pixel microscopy
The march of the Neo-Baroque zombie : From human to hunger
No full textCould the zombie—as paradoxical as it may seem—possibly embody the subjectivity of our era? To what extent can the aesthetic and formal parallels identified by Omar Calabrese between the Baroque and our era be detected in the corporeal status concerning death? To tease out some possible answers to these questions, we will attempt to connect and contrast the concepts of Baroque and Neo-Baroque through the zombie figure as an inflexion point between the two religious and ideological territories. To this end, we will focus on the concept of the body and the notion of limits in the different epochs. Our starting hypothesis is that the zombie is a privileged textual operator for understanding two views of death in dialogue with each other: a Baroque view where the remains of the body are representative of an explicit acceptance of death (memento mori) guaranteed by the theological propositions of the age, in contrast with a Neo-Baroque view in which the logic of capital transcends any notion of spirituality so that the zombie embodies the promise of an interminable physical experience
Análisis y correlación de parámetros estructurales y funcionales antes y después de la cirugía de la catarata. Aportación del índice de dispersión ocular (OSI)
No full textLa catarata es un proceso crónico asociado al envejecimiento, cuya definición es el desarrollo de opacidad en el cristalino que provoca disminución de la agudeza visual. La determinación de parámetros objetivos y fiables puede ayudar al clínico en la toma de decisiones previa a la cirugía, permitiendo la optimización del procedimiento. Esta tesis doctoral trata de Investigar la relación entre las clasificaciones clínicas actuales de la catarata y diferentes parámetros objetivos y subjetivos asociados a la pérdida de visión, así como la relación entre el objective scatter index (OSI), la cantidad de energía ultrasónica disipada durante la cirugía y la pérdida de células del endotelio corneal tras ésta.Cataract is a chronic, age-related process defined by the development of lens opacification that results in decreased visual acuity. The determination of objective, reliable parameters can assist clinicians in preoperative decision-making for cataract surgery, thereby enabling optimization of the procedure. This doctoral thesis investigates the relationship between the Ocular Scatter Index (OSI) and the amount of ultrasound energy used during surgery, as well as its association with current clinical cataract grading systems and other objective parameters linked to vision loss. It also examines additional subjective indicators of vision-related quality of life, assessed before and after surgery.Programa de Doctorat en Ciències de la Infermeri
Novel neutral and ionic metal-organic frameworks for sustainable catalytic processes
No full textThis thesis explores new strategies for designing and enhancing the chemical reactivity of metal-organic frameworks (MOFs) to convert waste into valuable chemical products. MOFs were synthesized in combination with 3D-printed polymers and ionic liquids, forming composite materials with improved catalytic performance due to the high dispersion of active sites. Functionalization was achieved by anchoring amino acids to the MOFs, creating multifunctional materials under mild, environmentally friendly conditions using non-toxic, abundant metals and bio-based ligands. Various synthesis methods based on classical, solvent-assisted, and rapid green, onepot approaches were used to develop and characterize these materials. The resulting MOFs were effective in reactions relevant to waste valorization, such as CO₂ fixation and carbonyl activation, operating under mild conditions without additives. The materials demonstrated superior activity, stability, and reusability, aligning with principles of green and circular chemistry, and contributing to the development of advanced heterogeneous catalysts for sustainable chemical processes.Programa de Doctorat en Química Sostenibl
Quantification of Gaseous Products Evolved at Industrially Relevant Current Densities During CO2 Electroreduction and Water Electrolysis Using Online Gas Chromatography
No full textThe quantification of gaseous chemicals such as CO and H2, obtained during the electrochemical reduction of CO2 or water using online gas chromatography (GC), is extremely relevant for the evaluation of an electrolysis system's performance. Herein, the causes that may hinder the proper calculation of Faraday efficiencies, when applying industrially relevant current densities, are demonstrated for both water electrolysis and CO2 electroreduction (eCO2RR). The findings highlight that rigorous calibration and an understanding of GC linearity and detection limits are essential for accurate measurement and quantification. Furthermore, the implementation of product dilution immediately after the electrocatalytic reactor, prior to GC analysis, is introduced as a versatile approach that enables reliable product quantification across different applied current densities and GC systems.C.A., R.R.L.M., and B.N.J. acknowledge funding by the Federal Ministry of Research, Technology and Space (BMFTR) in the framework of the NanomatFutur project “MatGasDif” (03XP0263). I.S., T.C.S., and C.A. acknowledge funding by the Ministry of Culture and Science of the State of North Rhine-Westphalia (PB NRW 2022 - Application 19)
Systematic review and meta-analysis of methodological approaches for characterising airborne SARS-CoV-2 RNA for environmental surveillance
No full textSARS-CoV-2 has transformed our understanding of respiratory disease transmission, particularly through aerosols. This systematic review examines studies published up to October 2, 2024 and focused on filter-based sampling methods reviewing key sampling and molecular diagnostic parameters to characterise airborne SARS-CoV-2 RNA from filters. A total of 84 studies were reviewed, yielding 104 datasets from different environments, including 70 studies indoors, 8 outdoors and 6 sampling both indoors and outdoors. The findings suggest that sampling volume, type of filter and storage conditions after sampling affect the detection positivity rate of SARS-CoV-2 genetic material in aerosols sampled near infected individuals indoors. No sampling or analytical parameters were identified to be associated with detection or quantification. Further experiments are recommended to ascertain the optimal methodological parameters for characterising SARS-COV-2 RNA in aerosols for environmental surveillance, including early warning systems, non-intrusive environmental monitoring, managing COVID-19 outbreaks and characterising viral airborne transmission