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Protecting privacy in the age of big data: exploring data linking methods for quasi-identifier selection
Get PDFThis paper explores the limitations faced by current solutions for selecting quasi-identifying attributes in the context of Privacy-Preserving Data Publishing (PPDP). PPDP stipulates that any published personal data should not be linkable to other available data sources in a manner that could potentially lead to individual re-identification or compromise sensitive data. The state-of-the-art methods for selecting quasi-identifying attributes commonly rely on heuristic evaluations to assess the risk of re-identification associated with each attribute. We hypothesize that these heuristic-based methods could be significantly improved by complementing them with empirical methods capable of quantifying the external linkability of dataset attributes. This empirical layer would enable a fine-tuning of the obfuscation of attributes within the dataset, thereby preventing the unnecessary privatization of attributes beyond potential attackers’ reach while ensuring privatization of those easily accessible. For this purpose, we explore recent advancements in identifying semantically related datasets across heterogeneous data sources. Although initially developed for purposes beyond privacy preservation, these methods support our initiative by uncovering potential links with external data and thus providing empirical evidence for the identification of attributes as quasi-identifiers. Finally, we discuss potential pathways to implement this empirical layer in quasi-identifier identification systems
Experimental validation of a simplified CFD model for a PCM-water finned heat exchanger
Get PDFThe most widely used numerical models in the scientific literature for simulating heat exchangers with phase change materials (PCMs) and water as the heat transfer fluid, are based on computational fluid dynamics (CFD) techniques, with the modelling of phase change being the key issue. The consideration of phase change effect, as well as the resolution of the movement of the PCM in the liquid state, make CFD models computationally very expensive. However, various published experiments indicate that during the heat discharge process, the dominant heat transfer mechanism is conduction in the solidified PCM around the finned tube. For this reason, this article presents a simplified CFD model, where convective flow of the PCM is neglected during the discharge process. The model was validated experimentally, and to achieve this validation process, an experimental prototype of a one-meter-long axially finned heat exchanger with four fins was built. Inlet and outlet water temperatures were continuously recorded, along with temperatures at various points inside the PCM, under four different water flow rates. The proposed numerical model was able to predict the outlet water temperature with an error smaller than 1◦C in all cases, and to capture the observed trend in temperature inside the PCM
Self-Medication Practice and Associated Factors Among Health Professionals in Spain
Get PDF(1) Background: Self-medication, defined as the use of medications without professional supervision, is a common practice that presents both potential benefits and significant risks. This study analyzes the prevalence, patterns, and determinants of self-medication among health professionals in Spain. (2) Methods: A cross-sectional descriptive design was employed with 438 health professionals, predominantly women (81.1%), with a median age of 42 years. The majority of the healthcare workers were nurses (45%). (3) Results: The results revealed a high prevalence of self-medication (59.4%). Analgesics and anti-inflammatory drugs were the most commonly used. Age and professional knowledge emerged as significant factors influencing this behavior. The main reasons for self-medication included the mildness of symptoms, easy access to medications, and previous successful experiences. Digital sources, especially websites, were the most consulted. Confidence in artificial intelligence tools as a clinical resource was moderate, with 18% of participants consulting AI tools, a rate comparable to the 19.5% for scientific databases. Logistic regression analysis identified age, knowledge of recommended doses, and perceived efficacy as significant predictors, while concern about risks acted as a protective factor. (4) Conclusions: This study highlights the need for educational interventions aimed at promoting responsible self-medication practices and mitigating associated risks among healthcare professionals
Is User Perception the Key to Unlocking the Full Potential of Business Process Management Systems (BPMS)? Enhancing BPMS Efficacy Through User Perception
Get PDFThis study investigates factors influencing employees' perceptions of the usefulness of Business
Process Management Systems (BPMS) in commercial settings. It explores the roles of system
dependency, system quality, and the quality of information and knowledge in the adoption and use
of BPMS. Data were collected using a structured questionnaire from end-users in various firms and
analyzed with Partial Least Squares (PLS). The survey evaluated perceptions of service quality, input
quality, system attributes, and overall system quality. The findings indicate that service quality, input
quality, and specific system attributes significantly influence perceived system quality, while system
dependency and information quality are predictors of perceived usefulness. The results highlight
the importance of user training, support, and high-quality information in enhancing satisfaction
and BPMS. This research offers empirical evidence on the factors impacting user perceptions and
acceptance, emphasizing the need for user-centric approaches in BPMS
Estudio experimental de soldaduras MAG y soldaduras híbridas (HLAW) en acero de alta resistencia s700mc
Get PDFEste estudio experimental analiza y compara diferentes técnicas de soldadura aplicadas al acero de alta resistencia S700MC, un material clave en la industria debido a su excelente relación resistencia-peso y su aplicabilidad en sectores como el offshore, la energía eólica y la fabricación de estructuras metálicas de alto rendimiento.
El trabajo se centra en tres procesos de soldadura: MAG, LBW y HLAW, evaluando sus ventajas, limitaciones y calidad de unión en función de diversos ensayos mecánicos y metalográficos. A través de un enfoque experimental, se han determinado los parámetros óptimos para mejorar la eficiencia y calidad de las soldaduras híbridas, con el objetivo de facilitar su implementación en entornos industriales exigentes.
Los resultados obtenidos en este estudio servirán como base para futuras investigaciones y optimización de procesos en soldadura de aceros avanzados, contribuyendo a la innovación y desarrollo de nuevas tecnologías de unión.Este trabajo de fin de grado se centra en el estudio de diferentes técnicas de soldadura aplicadas al acero de ultra alta resistencia S700MC, un material utilizado en sectores industriales exigentes como el offshore, torres eólicas y grúas telescópicas. Se analizan tres procesos de soldadura:
- MAG (Metal Active Gas), un proceso convencional de soldadura por arco con gas activo.
- LBW (Laser Beam Welding), que emplea un láser para unir las piezas sin aporte de materal.
- HLAW (Hybrid Laser Arc Welding), una combinación de soldadura por láser y arco eléctrico que mejora la penetración, velocidad y calidad del proceso.
El estudio experimental incluye pruebas en placas de acero de 8 mm de espesor utilizando la configuración Bead On Plate (BOP). Se han evaluado la calidad de las soldaduras mediante ensayos destructivos y no destructivos, como inspección visual, ensayos de tracción, pruebas de impacto Charpy, análisis metalográficos y medición de dureza.
El objetivo principal es optimizar los parámetros del proceso HLAW para obtener soldaduras de alta calidad y velocidad adecuadas para aplicaciones industriales. Los resultados obtenidos permitirán extender este conocimiento a configuraciones más complejas, como uniones a tope o en T, ampliando así las posibilidades de aplicación del acero S700M
Discovery of Novel Phenolic Compounds from Eutypa lata Through OSMAC Approach: Structural Elucidation and Antibiotic Potential
No full textAmong grapevine trunk diseases, Eutypa dieback, caused by the fungus Eutypa
lata, is one of the most critical ones, due to its widespread infection in vineyards and the
lack of effective treatments. This fungus is a vascular pathogen that enters grapevines
through pruning wounds. The infection process is associated with phytotoxic metabolites produced by the fungus, and as such, the identification of new metabolites from
different culture conditions and broths could provide valuable insights into the fungus’s
enzymatic system and help its control. For the purposes of this study, the OSMAC (one
strain, many compounds) approach was applied to investigate the secondary metabolism
of E. lata strain 311 isolated from Vitis vinifera plants in Spain. A total of twenty metabolites were isolated, including five reported for the first time from E. lata and four that
are newly identified compounds in the literature: eulatagalactoside A, (R)-2-(4′
-hydroxy3
′
-methylbut-1′
-yn-1′
-yl)-4-(hydroxymethyl)phenol, (S)-7-hydroxymethyl-3-methyl-2,3-
dihydro-1-benzoxepin-3-ol, and (3aR,4S,5R,7aS)-4,5-dihydroxy-6-((R)-3′
-methylbuta-1′
,3′
-
dien-1′
-ylidene)hexahydrobenzo[d][1,3]dioxol-2-one. These compounds were extracted
from fermentation broths using silica gel column chromatography and high-performance
liquid chromatography (HPLC). Their structures were elucidated through extensive 1D
and 2D NMR spectroscopy, along with high-resolution electrospray ionization mass spectrometry (HRESIMS). Compounds were evaluated for phytotoxicity against Phaseolus
vulgaris, with only eulatagalactoside A producing white spots after 48 h. Additionally, the
antibacterial activity against Escherichia coli, Staphylococcus aureus, and Klebsiella pneumoniae of
selected compounds was tested. The compounds (R)-2-(4′
-hydroxy-3′
-methylbut-1′
-yn-1′
-yl)-
4-(hydroxymethyl)phenol and (S)-7-(hydroxymethyl)-3-methyl-2,3-dihydrobenzo[b]oxepin-3-
ol showed the most significant antimicrobial activity against Gram-positive bacteria, inhibiting
S. aureus by over 75%, with IC50 values of 511.4 µg/mL and 617.9 µg/mL, respectivel
Finite Element Simulation of Hot Rolling for Large-Scale AISI 430 Ferritic Stainless-Steel Slabs Using Industrial Rolling Schedules—Part 2: Simulation of the Roughing Stage and Comparison with Experimental Results
No full textModeling hot rolling remains a major challenge in computational solid mechanics.
It demands the simultaneous consideration of geometric and material responses. Although
the finite element method (FEM) is widely used, multi-pass simulations often treat each
pass independently, leading to error accumulation, particularly in flat product rolling,
where inter-pass interactions are crucial. Advanced models and remeshing techniques
have been developed to address these issues, but substantial computational resources are
required. In this study, a previously validated and simplified 3D FEM model was employed
to simulate the initial stages of the hot rolling of large-scale AISI 430 ferritic stainlesssteel slabs, using data from an industrial rolling schedule. Specifically, the simulations
encompassed preheating and descaling, and seven passes of the roughing stage. Through
these simulations, a transfer bar with an approximate length of 16,100 mm was obtained.
The simulated thickness and rolling load values were compared with experimental data,
demonstrating good agreement in most passes. Subsequently, the temperature, effective
plastic strain, and equivalent stress distributions along the rolled material were extracted
and analyzed. The results highlighted that the employed model adequately predicted the
variations in the analyzed parameters throughout the volume of the rolled material during
the different stages of the process. However, discrepancies were identified in the rolling
load values during the final passes, which were attributed to the presence of phenomena
not considered in the constitutive model used. This model will be refined in future studies
to reduce the error in the rolling load estimation
Impact of transformational leadership, happiness management, and work stress on turnover intention
No full textIn the context of ongoing labour transformation and increasing talent turnover, understanding the factors
influencing employee retention has become a strategic priority for modern organisations. This study analyses
the effect of transformational leadership on turnover intention, incorporating happiness management and
work-related stress as mediating variables. Additionally, it explores potential differences between Mexico’s
public and private sectors. A quantitative, non-experimental, and cross-sectional design was employed, using a
structured questionnaire administered to a sample of 414 employees from various educational, governmental,
and corporate institutions. Data were analysed through Covariance-Based Structural Equation Modelling (CBSEM)
and multigroup analysis. The results indicate that transformational leadership positively influences
happiness management, reducing stress and turnover intention. Although work-related stress increased turnover
intention, its mediating effect was not statistically significant. Sectoral differences were also observed: in the
private sector, transformational leadership acted as a buffer against stress, whereas in the public sector,
happiness management played a stronger role in reducing turnover. The proposed model contributes to the
advancement of Social Exchange Theory by incorporating emotional mechanisms as key explanatory factors for
employee retention. The findings offer valuable insights for developing human-centred organisational policies
tailored to sector-specific dynamics and aligned with the Sustainable Development Goals related to decent
work and emotional wellbeing
Evaluación de los efectos de la densidad de cultivo sobre el crecimiento y metabolismo de juveniles de lisa (Chelon labrosus)
No full textLa acuicultura se encuentra en pleno proceso de expansión global debido al aumento de
la demanda de productos acuáticos y a la creciente preocupación por la sobreexplotación
de los recursos naturales. Para garantizar el crecimiento sostenible del sector, es
imprescindible optimizar diversos parámetros físicos y biológicos. Esto implica
minimizar cualquier fuente de estrés que pueda afectar el bienestar animal, garantizando
así su salud y el rendimiento productivo. En este contexto, el presente Trabajo de Fin de
Grado tiene como objetivo analizar el impacto de la densidad de carga sobre el
crecimiento y metabolismo de juveniles de lisa (Chelon labrosus), una especie con
potencial para una acuicultura sostenible. Para ello, 225 ejemplares de lisa se
distribuyeron en seis tanques con dos densidades de carga: baja (LSD, 2 kg/m³) y alta
(HSD, 11 kg/m³) y se alimentaron ad libitum con un pienso comercial durante 147 días.
Tras finalizar el experimento, se se evaluaron parámetros biométricos, zootécnicos,
somáticos y metabólicos en distintos tejidos (plasma, hígado, mucus epidérmico).
Los resultados indican que la densidad de cultivo no tuvo un impacto significativo en el
crecimiento de los juveniles de lisa. No obstante, se observó una tendencia positiva en la
eficiencia de alimentación en la densidad alta, lo que sugiere que los peces en estas
condiciones podrían haber optimizado el aprovechamiento del alimento, mejorando su
eficiencia energética. Por otro lado, los peces de ambos grupos experimentales
consiguieron mantener la homeostasis metabólica a nivel plasmático, lo que indica una
adaptación fisiológica a las condiciones de cultivo. Sin embargo, en el hígado de los
individuos cultivados en baja densidad se detectó una mayor actividad del metabolismo
anaeróbico, lo que sugiere una posible reutilización del lactato mediante gluconeogénesis
en el ciclo de Cori, permitiendo así la generación de energía adicional.
El estudio revela que la densidad de cultivo influye en el metabolismo de Chelon
labrosus, aunque no permite determinar con exactitud la densidad óptima para esta
especie. A pesar de que las densidades probadas no afectaron el crecimiento, las
diferencias metabólicas observadas destacan la necesidad de continuar investigando para
optimizar la producción de esta especie y asegurar su bienestar en condiciones de cultivo.Aquaculture is currently undergoing rapid global expansion due to the increased demand
for aquatic products and growing concerns about the overexploitation of natural
resources. To ensure the sustainable growth of the sector, it is essential to optimize various
physical and biological parameters. This involves reducing any source of stress that could
affect animal welfare, thereby ensuring optimal health and productive performance. In
this context, the aim of this study is to analyse the impact of stocking density on the
growth and metabolism of juvenile Chelon labrosus, a species with potential for
sustainable aquaculture. To evaluate this 225 individuals of Chelon labrosus were
distributed to six tanks with two stocking densities: low (LSD, 2 kg/m³) and high (HSD,
11 kg/m³) and fed ad libitum with a commercial diet for 147 days. After the experimental
trial was completed, biometric, zootechnical, somatic and metabolic parameters were
evaluated in different tissues (plasma, liver, skin mucus).
The results indicate that stocking density did not have a significant impact on the juvenile
growth of Chelon labrosus juveniles. However, a positive trend in feeding efficiency was
observed in the high-density group, suggesting that fish under these conditions may have
optimized food utilization, improving their energy efficiency. On the other hand, fish from
both experimental groups maintained plasma metabolic homeostasis, indicating a
physiological adaptation to the rearing conditions. However, in the liver of fish from the
low-density group, higher anaerobic metabolism activity was detected, suggesting the
potential reutilization of lactate through gluconeogenesis in the Cori cycle, thereby
generating additional energy.
The study reveals that stocking density influences the metabolism of Chelon labrosus,
although it does not allow for the precise determination of the optimal density for this fish
species. Although the tested densities did not affect growth, the observed metabolic
differences highlight the need for further research to optimize the production of this
species and ensure its well-being under culture conditions
CIANYS 2021. Actas del I Congreso Iberoamericano de Arqueología Náutica y Subacuática
No full textEl I Congreso Iberoamericano de Arqueología Náutica y Subacuática (CIANYS 2021), celebrado en Cádiz en octubre de 2021, supuso un hito en la consolidación de esta disciplina en el ámbito iberoamericano. Más de 250 autores y coautores, procedentes de universidades, centros de investigación y equipos profesionales de distintos países, presentaron un total de 128 comunicaciones y pósteres que abarcaron desde la construcción naval prehistórica hasta las estrategias actualizadas de gestión del patrimonio cultural subacuático.
Las actas que ahora se publican constituyen un testimonio de la diversidad y vitalidad de la investigación en arqueología náutica y subacuática. Estructuradas en trece sesiones temáticas, recogen estudios sobre cargamentos y rutas comerciales, espacios portuarios, paisajes culturales marítimos y fluviales, técnicas de arqueometría, aplicación de tecnologías digitales, conservación de materiales, gestión y difusión patrimonial, así como debates en torno a la Convención de 2001 de la Unesco.
El volumen refleja no solo el estado actual de la disciplina, sino también los retos de futuro: la necesidad de afianzarla en el ámbito académico, la necesidad de fomentar la colaboración interdisciplinar y el papel fundamental de la sociedad en la preservación de este tipo de patrimonio. Asimismo, pone de relieve el papel de la Universidad de Cádiz como referente académico y motor de iniciativas que promueven la cooperación científica internacional.
Estas actas no son un punto de llegada, sino de partida: una invitación a seguir construyendo una arqueología más global, abierta y comprometida, con el deseo de que pronto podamos reunirnos nuevamente en una segunda edición de este congreso