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Estimated exposure of flame-retardants in Spanish toddlers: a modelling approach
No full textFlame retardants (FRs) are chemicals used to reduce the flammability of materials and are commonly found in
consumer products such as furniture and electronics. These substances can migrate from products (e.g., furniture
foam and electronic devices) into indoor environments such as air and dust and may pose risk to human health by
direct exposure. Some FRs are known endocrine disruptors capable of affecting thyroid hormone homeostasis,
neurodevelopment, behaviour and reproduction. Thus, there is a need to understand the emission, transport,
sorption, and distribution of FRs. In line with the 3R principles (Reduce, Replace and Refine) used in scientific
research and risk assessment, modelling has become a valuable tool for elucidating and predicting the emissions,
behaviour and fate of semi-volatile organic compounds (SVOCs) in indoor environments. i-SVOC is a software
application designed for dynamic modelling of these chemicals covering indoor compartments contributing to a
more efficient evaluation of indoor pollution. This study had two main objectives. First, we aimed to develop and
validate a model to estimate the concentrations of two FRs, tris(chloroisopropyl)-phosphate (TClPP) and triphenyl phosphate (TPhP) in Spanish indoor environments. Second, we sought to estimate the indoor levels and
exposure to both FRs in Spain by modelling environmental data from a toddler Spanish birth cohort (GENEIDA).
Four scenarios were simulated using the i-SVOC software, considering variation in ventilation (high/low) and
emissions factors (high/medium). This study demonstrated the ability of i-SVOC model to estimate TClPP and
TPhP concentrations in air and dust. The application of the model to environmental data from the GENEIDA
cohort showed statistically similar mean/median values to those experimentally collected, leading to comparable
estimates of FR-exposure. Furthermore, the non-carcinogenic risk from exposure to TClPP and TPhP in toddlers
were assessed. However, no correlation was found between the estimated exposure levels and the measured
concentrations of FR metabolites (bis(1-chloro-2-propyl) phosphate -BClPP- and diphenyl phosphate -DPhP-) in
the cohort toddlers. This discrepancy is likely due to variability in environmental characteristics and individual
differences in metabolite concentrations.MCIU/AEI/ERDF (FLAMERISK project,
grant number RTI2018-095466-B-I00)European Union’s Horizon Europe (Grant Agreement No 101057014
Ultrasound-Guided Versus Traditional Refill of Intrathecal Infusion Pumps: A Prospective Quasi-Experimental Clinical Study
No full textBackground: There are multiple treatments and approaches available to manage pain. However, when these interventions fail to achieve adequate relief, pain management may involve the implantation of intrathecal infusion pumps. The use of ultrasound guidance may enhance nursing practice by improving procedural efficiency and patient comfort. This technique offers a more precise, safer, and less painful approach, potentially increasing patient satisfaction and reducing procedural complications. Aim: To evaluate patient pain levels during intrathecal infusion pump refills under ultrasound guidance compared to the traditional approach, also aiming to determine the time taken per technique and to assess related intra-procedural complications. Design: A prospective quasi-experimental pre-post study. Methods: The study population included individuals with intrathecal infusion
pumps. Each participant underwent two refill visits: one using the traditional method and the subsequent refill using ultrasound guidance. The time required to complete the procedure, any complications, and pain related to the procedure were measured for both techniques. Time was measured using a stopwatch, and pain was assessed at the end of each procedure using a Visual Analogue Scale (VAS). Results: A total of 45 patients (25 men and 20 women), with a median age of 56.0 years were included. The estimated mean refill duration was 13.67 min for the traditional method versus 7.26 min for ultrasoundguided refills, representing a 53.2% reduction. The adjusted mean VAS was 2.76 (2.27–3.24) with ultrasound versus 5.91 (5.20–6.62) with the traditional method, yielding an adjusted mean difference of −3.16 (−4.02 to −2.30; p < 0.001). Reductions were consistent across subgroups defined by sex, refill duration, inter-procedural interval, intrathecal medication, and medical history. Complications occurred in 20.0% of traditional refills but in none of the ultrasound-guided procedures. Conclusions: Ultrasound guidance significantly
reduces pain, complications, and procedure time, positioning it as the new standard of care for intrathecal pump refills. This mandates its immediate integration into nursing protocols and health management policies
Propuesta de planificación para mejorar la empleabilidad de los jóvenes en la isla de El Hierro
No full textEl presente Trabajo de Fin de Máster “Propuesta de planificación para mejorar la
empleabilidad de los jóvenes en la isla de El Hierro” surge de la necesidad de afrontar la
problemática del éxodo de la juventud herreña cualificada en un territorio con una riqueza
natural única y con grandes posibilidades. La principal problemática que se encuentra la isla
de El Hierro, y otras islas vecinas, es la pérdida de población joven preparada por la falta de
oportunidades en su tierra. A través de este plan se pretende aportar medidas y líneas de
actuación realistas que permitan fortalecer el mercado de trabajo local, impulsar nuevos
sectores emergentes y crear empleos de calidad, bajo un enfoque de sostenibilidad, igualdad
de género y participación ciudadana. Igual de importante es generar oportunidades para las
personas que desean desarrollar su proyecto personal y profesional en su tierra y que por falta
de oportunidades se ven obligados a emigrar a otros territorios. Este estudio se sustentado un
diagnóstico de la realidad insular, con la definición de objetivos, líneas de actuación y
mecanismos de evaluación. La pequeña dimensión de su territorio y población hace de la isla
un laboratorio para la puesta en marcha de iniciativas. Esto permite convertir a El Hierro en
un ejemplo de desarrollo equilibrado y de arraigo del talento jove
Carbohydrate-Based Chiral Ligands for the Enantioselective Addition of Diethylzinc to Aldehydes
No full textBackground: Carbohydrate-derived chiral ligands are promising tools in asymmetric catalysis due to their structural diversity, chirality, and availability. However, ligands based
on galactose or sorbose have been scarcely explored in the enantioselective addition of
dialkylzinc reagents to aldehydes. Methods: A series of chiral diols and β-amino alcohols was synthesized from methyl D-glucopyranoside, methyl D-galactopyranoside, and
D-fructose. These ligands were tested in the titanium tetraisopropoxide-promoted enantioselective addition of diethylzinc to aromatic and aliphatic aldehydes. Results: Several
ligands, particularly those with a D-fructopyranose backbone, exhibited excellent catalytic
activity, with conversion rates up to 100% and enantioselectivities up to 96% ee. Notably,
this study reports for the first time the use of β-amino alcohols derived from fructose and
sorbose in this transformation. Conclusions: Carbohydrate-based ligands represent effective, inexpensive, and structurally versatile scaffolds for developing highly enantioselective
catalysts, expanding the utility of sugars in asymmetric organometallic reactions.Junta de Andalucía (P09-FQM-4498
Reflexiones sobre la Optimización Cónica Entre la Teoría y las Aplicaciones
No full textLa presente disertación explora nuevas perspectivas sobre la optimización
cónica, abarcando una amplia gama de temas que van desde la optimización
lineal sobre secciones de conos hasta aplicaciones en diseño de redes complejas,
localización de servicios, detección de fugas o geometría algebraica real.
El concepto central del trabajo es la noción matemática de cono, que se explora
desde sus orígenes geométricos hasta su uso en la teoría moderna de la
optimización. El trabajo se basa, máxime, en el estudio de problemas de optimización
cónica, donde se minimiza una función lineal sobre la sección de
un cono. Esto generaliza la programación lineal e incluye una amplia gama
de problemas de optimización.
Uno de los principales propósitos de esta tesis es introducir una nueva
familia de conos, los conos de potencia generalizados, y estudiar el problema
de minimizar una función lineal sobre ellos. Se realiza un análisis detallado
sobre las representaciones minimales de estos conos, proporcionando un procedimiento
para construir representaciones minimales utilizando conos de
segundo orden cuando los parámetros definitorios son racionales. La construcción
se basa en el concepto de grafos mediados, una estructura combinatoria
que desempeña un papel crucial en la derivación de estas representaciones
minimales.
La metodología utilizada supone el desarrollo de resultados teóricos
sobre las propiedades de los conos de potencia generalizados, el análisis
de grafos mediados y la exploración de resultados de complejidad para el problema de factibilidad sobre conos de orden p. Se derivan nuevas cotas
de complejidad, mejorando los resultados existentes y llevando a una mejor
comprensión de los desafíos computacionales de la optimización cónica.
Los hallazgos tienen aplicaciones directas en varios dominios. Una
aplicación importante se encuentra en los problemas de ubicación de instalaciones,
donde se aplica la geometría de los conos de potencia generalizados
para desarrollar un modelo de optimización basado en la ley de la gravitación
universal de Newton. Además, se presenta un enfoque novedoso
para la detección de fugas en redes de tuberías, formulado como un problema
entero mixto sobre conos de orden p. Las soluciones a estos problemas
son computacionalmente eficientes y demuestran la utilidad práctica de los
enfoques propuestos.
En conclusión, la disertación contribuye tanto a los avances teóricos en
optimización cónica como a metodologías prácticas para aplicaciones en el
mundo real, ofreciendo una perspectiva unificada sobre la optimización, la
geometría algebraica y la combinatoria.This dissertation explores novel insights into conic optimization, bridging a
diverse set of topics ranging from linear optimization over slices of cones to
applications in complex network design, facility location, leak detection, or
real algebraic geometry. The central concept of the work is the mathematical
notion of cone, which is explored from its geometric origins to its use
in modern optimization theory. The work is grounded in the study of conic
optimization problems, where a linear function is minimized over a slice of a
cone. This generalizes linear programming and encompasses a broad range
of optimization problems.
One of the main purposes of this thesis is to introduce a new family
of cones, generalized power cones, and study the conic optimization problem
of minimizing a linear function over these cones. A detailed analysis is
conducted on the minimal representations of these cones, providing a procedure
for constructing minimal representations using second–order cones
when the defining parameters are rational. The construction is grounded in
the concept of mediated graphs, a combinatorial structure that plays a crucial
role in deriving the minimal representations.
The methodology involves the development of theoretical results on
the properties of generalized power cones, the analysis of mediated graphs,
and the exploration of complexity results for the feasibility problem over p–
order cones. New complexity bounds are derived, improving upon existing
results and leading to a better understanding of the computational challenges
in conic optimization. The findings have direct applications in several domains. A significant application
is found in facility location problems, where the geometry of generalized
power cones is applied to devise an optimization model based on Newton’s
universal law of gravitation. Additionally, a novel approach to leak
detection in pipeline networks is presented, formulated as a mixed integer
p–order cone program. The solutions to these problems are computationally
efficient and demonstrate the practical utility of the proposed approaches.
In conclusion, the dissertation contributes to both theoretical advancements
in conic optimization and practical methodologies for real-world applications,
offering a unified perspective on optimization, algebraic geometry,
and combinatorics.Tesis Univ. Granada
Mentoría Pedagógica y Docente, Formación de Tutores y Evaluación de Prácticas Externas: Sinergias entre Tutores Escolares, Profesorado Universitario de las Especialidades de Música (Facultad de Educación- UCM y Facultad de Geografía e Historia- UGR) y Alumni Universitarios
No full textEl presente Proyecto de Innovación Docente centra sus esfuerzos en ofrecer acciones innovadoras de ayuda y seguimiento referentes a acciones dedicadas a la mentoria y a la evaluación de las prácticas externas tanto para alumnado como para profesorado de la especialidad de Educación Musical de la Universidad Complutense de Madrid, Universidad de Granada y Universidad Autónoma de Madrid. Dicha propuesta, parte del valor otorgado a las prácticas externas en cuanto a su valiosa aportación en acciones destinadas a la evaluación formativa y continua. Esta incluye tanto la retroalimentación facilitada por los tutores supervisores de los centros escolares y en su caso, de los mentores, como la propia autoevaluación y reflexión del alumnado con la que dicho profesorado puede obtener una perspectiva más completa de lo que es un desempeño docente adecuado.Universidad Complutense de Madri
Ict usage, social networks, interactivity, and satisfaction: an exploration of travel behavior for students from three European countries
No full textThis study examines the impact of Information and Communication Technologies (ICT) on students’ travel and social behaviors in three European cities: Lisbon, Granada, and Zagreb. Drawing on a sample of 2,455 university students, the research examines the interplay between ICT usage (ICTU), social network size (SNS), perceived usefulness (PU) of ICT, patterns of interaction behavior (IB) (both online and face-to-face), and overall satisfaction (SA) with social relationships. The study employs structural equation modelling to capture both direct and indirect relationships among these factors, and incorporates a MIMIC approach to account for socio-demographic and contextual heterogeneity. The results show that ICT usage has mostly indirect effects on perceived usefulness, interaction behavior, and satisfaction, operating through social network size and interaction behavior. Social network size acts as a key mediator, linking ICT use to other variables, and is also the strongest predictor of interaction behavior. Similarly, perceived usefulness and traditional social networks emerge as the most influential factors shaping satisfaction. The findings confirm that online interactions tend to reinforce, rather than replace, face-to-face contact. Furthermore, a larger traditional network is associated with a larger online network, though not vice versa. Overall, the study highlights the complex, mediated pathways through which ICT use shapes young people’s social engagement and satisfaction, offering valuable insights for transport researchers and policymakers seeking to understand evolving mobility patterns.Partially funded by the COST Action TU 1305 “Social Networks and Travel Behavior
Calcium and iron promote reversible self‑assembly of dissolved organic matter into particles
No full textDissolved organic matter (DOM) consists of dissolved molecules, biopolymers, and aggregates with a broad range of molecular sizes. In freshwater and seawater environments, spontaneous self-assembly of DOM forms hydrated particulate organic matter (POM) networks. This conversion from DOM to POM affects carbon transfer through microbial and particle food webs and export to sediments. Particle food webs are based on the direct POM ingestion by zooplankton species. This DOM assembly occurs when the inter-polymer or inter-colloid distances allow chemical (covalent) or physical (e.g., electrostatic, hydrogen) bonds. Here we explore the underlying mechanisms of self-assembly using lake waters with different concentrations of polyanionic DOM with humic content and calcium (Ca) and iron (Fe) crosslinking. We experimentally adjusted the cations by chelating and/or increasing the concentration of calcium or iron. To monitor the self-assembly of DOM, we employed homodynamic laser scattering. Results indicate that DOM self-assembly and physical gel-particle formation result from low-energy Ca+2 and Fe+3 counterion bonding. It can be readily reversed by Ca and Fe chelators, resulting in the disassembly of the network and dispersion of DOM polymers. Calcium cations appear to promote a higher level of self-assembly, reaching larger hydrodynamic sizes during stabilization, compared to iron cations. Our results indicate that the chemical environmental context critically affects the formation of POM from DOM, influencing ecosystem processes such as carbon sedimentation and storage, and providing alternative pathways for heterotrophic consumers (i.e., food webs based on particles).Ministerio de Ciencia, Innovación y Universidades - (grant number PID2022.1378650B.100) (grant number MTM2017-91054-EXP
Comprehensive Analysis of Mycotoxins in Green Coffee Food Supplements: Method Development, Occurrence, and Health Risk Assessment
No full textThis study investigates the presence of mycotoxins in green coffee-based dietary supplements to ensure their safety, given the potential risks of contamination and the growing
interest in them among consumers. A sample treatment based on a salting-out assisted
liquid–liquid extraction (SALLE) followed by one-step solid-phase extraction (SPE) was selected for the extraction and clean-up of 15 mycotoxins followed by ultra-high performance
chromatography–tandem mass spectrometry detection (UHPLC-MS/MS). The target mycotoxins included aflatoxins (AFG1, AFG2, AFB1, AFB2), Alternaria toxins (AOH, AME, TEN),
ochratoxin A (OTA), fumonisins (FB1, FB2), zearalenone (ZEN), trichothecenes (T-2, HT-2),
enniatin B1 (ENNB1), and beauvericin (BEA). The proposed method was successfully
characterized, obtaining high recoveries, a satisfactory precision, and low detection limits.
Subsequently, the method was applied for the analysis of 16 commercial food supplements.
The analysis revealed the presence of mycotoxins in all samples investigated with Fusarium
mycotoxins as the most prevalent. The dietary exposure and risk characterization revealed
a low level of risk, except for AFs where chronic exposure in adults may lead to potential
health concerns.University of Parma - MUR (Italian Ministry of Universities and Research
Exploring multi-objective metaheuristics to optimise resource allocation in energy communities
No full textIn the transition to a sustainable urban model, renewable energy communities where participants act as both producers and consumers have gained substantial importance. In this context, the main challenge lies in the optimal sizing of energy generation and storage units to achieve a balance between economic profitability and independence from the conventional grid. In this study, we define the resource management problem for the initial setup of an energy community, optimising the number of solar panels, wind turbines, and battery capacity per member. Besides, the objective functions considered include the levelized cost of energy (LCOE), self-sufficiency, and self-consumption, evaluated under four different interaction models, from full independence to shared battery use. While metaheuristics are commonly employed in energy management problems, the increasing variety of algorithms complicates the selection of an effective optimisation method. We implemented several multi-objective metaheuristics, including Particle Swarm Optimisation, Marine Predators Algorithm, Whale Optimisation Algorithm, and Equilibrium Optimiser. Additionally, we introduce the Political Optimizer, specifically adapted for multi-objective optimisation, which provides an additional tool for this kind of problems. Results from simulations demonstrate that the Multi-Objective Equilibrium Optimiser with Archive Evolution Path achieved the lowest LCOE, 0.0736 /kWh, a self-consumption rate of 1.0000 and a self-sufficiency rate of 0.9509. Finally, the largest emission reductions were also observed with shared storage, and reached up to 38.1%.Grant PID2020-112495RB-C21 funded by MCIN/AEI/10.13039/ 50110001103