University of Cádiz
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Indoor Environmental Monitoring and Chronic Respiratory Diseases: A Systematic Review
Get PDFChronic respiratory diseases (CRD), which include Chronic Obstructive Pulmonary Disease (COPD) and asthma, are significant global health issues, with air quality playing a vital role in exacerbating these conditions. This systematic review explores how monitoring indoor air quality (IAQ) can help manage and reduce respiratory exacerbations in CRD patients. A search of the Web of Science database, yielding 301 articles, was conducted following PRISMA guidelines. Of these, 60 met the inclusion criteria, and after screening, 21 articles were analyzed. The review identified substantial gaps in current research: the lack of standardization in IAQ monitoring; the need for considering geographic variability and for long-term longitudinal studies; and the importance of linking monitored air quality data with respiratory health indicators. It also stressed the importance of considering the heterogeneity of patients in the methodological study design, as well as the convenience of introducing recommendation systems to assess the true impact of corrective measures on indoor air quality in the homes of chronic respiratory patients. The integration of home-based IAQ monitoring with machine learning techniques to enhance our understanding of the relationship between IAQ and respiratory health is emerging as a key area for future research. Addressing all these challenges has the potential to mitigate the impact of CRD and improve the quality of life for patients.This contribution has been supported by grant PID2021-126810OB-I00 funded by MICIU/AEI/10.13039/501100011033 and by ERDF/EU
Impact of the ambidexterity of University Technology Transfer Offices on their performance: The Spanish context
Get PDFUniversity Technology Transfer Offices (UTTOs) are units created to promote knowledge transfer. They assist academics by creating academic spin-offs (ASOs) and managing contracts, consulting, licenses, and patents. These units have grown in size, age, experience, and professionalism, thereby gaining resources and networks to improve UTTOs’' performance. However, neither the creation of these units nor the presence of these characteristics are sufficient to improve transfer performance. Organizational UTTO ambidexterity, as a dynamic capability, and individual UTTO ambidexterity, as the individual orientation of UTTO employees, seems necessary to address two exploitative and explorative orientations to improve knowledge transfer. Exploitative orientation aims to provide UTTO services by seeking improvement, efficiency, and incremental innovation. Explorative orientation is oriented toward seeking new opportunities to provide new UTTO services and identify new customers for radical innovation. This study analyzes the impact of organizational and individual ambidexterity of Spanish UTTOs on their transfer performance. The regression analysis indicates that the organizational ambidexterity of UTTOs is critical for the number of ASOs. In addition, individual ambidexterity is relevant for obtaining higher contract and consultancy incomes and licenses. By contrast, the impact of organizational and individual ambidexterity on patents is yet to be determined
Assessment of consolidants for the preservation of Tituli Picti on amphorae from the Ses Fontanelles late Roman shipwreck (Mallorca, Spain): An analytical approach
No full textThe ceramic materials from the Ses Fontanelles wreck are an exceptional find due to the large num- ber of amphorae with preserved inscriptions and their state of preservation. The presence of Tituli Picti is uncommon, and even less so in ceramics altered in an underwater environment. The bibliography on the conservation of these elements is scarce. This manuscript presents the results of a comparative study of two consolidation products: one based on nanoparticles (Nano Estel 1:1) and the other on an acrylic resin based on organic solvents (Paraloid B72 3 % in acetone).This preliminary study aims to es- tablish a methodology for the treatment of the inscriptions painted on Roman amphorae from the Ses Fontanelles wreck (Mallorca), 4th century AD. A suite of analytical techniques was employed, encompass- ing surface analysis via Scanning Electron Microscopy - Energy Dispersive X-Ray Spectroscopy (SEM-EDX), X-Ray Diffraction (XRD) for the identification of crystalline phases, hardness and micro-indentation test- ing, peeling test, and measurements of aesthetic alterations using a spectrophotometer and glossmeter. The results obtained from these analyses were found to be highly congruent, underscoring the effective- ness of a long-standing acrylic resin and the potential of the silica nanoparticle-based product, which has seen a surge in utilization. This study also paves the way for further research in this area, as it opens up new avenues for exploration and the potential discovery of additional findings.ARQUEOMALLORNAUTA project, together with the Universitat de Barcelona, Universidad de Cadiz & Universitat de les Illes Balears. This study was undertaken within the framework of the Laboratory of Historical Heritage Studies and Conservation (LEC-PH, INMAR) and the Nanomaterials Group (TEP-243) of the University of Cadiz. Projects GARVM IV (PID2022–138814OB-I00/MCIN/AEI) and MEDUSA (PCM_00031) have also been involved
Prediction and Detection of Localised Corrosion Attack of Stainless Steel in Biogas Production: A Machine Learning Classification Approach
Get PDFBiogas contributes to environmental protection by reducing greenhouse gas emissions and promoting the recycling of organic waste. Its utilization plays a crucial role in addressing the challenges of climate change and sustainability. However, the deterioration of process plants involved in biogas production due to corrosion has a critical impact on the safety and durability of their operations. In order to maintain the safety of structures in terms of service life with respect to corrosion, it is essential to develop effective corrosion engineering control methods. Electrochemical techniques have become a useful tool by which to evaluate corrosion resistance. However, these techniques may require microscopic analysis of the material surface and the analysis may be influenced by subjective factors. To solve this drawback, this work proposes the use of SVM models to predict the corrosion status of the material used in biogas production with no need to perform microscopic analysis after the electrochemical test. The obtained results of sensitivity and specificity equal to 0.94 and 0.97, respectively, revealed the utility of the proposed stochastic models to assure the corrosion state of the equipment involved in biogas production. SVM-based models are an effective alternative for accurately evaluating material durability and comparing the corrosion resistance of different materials in biogas environments. This approach facilitates the selection of the most suitable material to achieve greater durability and long-term performance. Synopsis: The results show that the proposed model is a useful tool to predict the behaviour of stainless steel against corrosion according to the environmental conditions to which the material is exposed in biogas production
The k-Distance Mutual-Visibility Problem in Graphs
Get PDFThe concept of mutual visibility in graphs, introduced recently, addresses a fundamental problem in Graph Theory concerning the identification of the largest set of vertices in a graph such that any two vertices have a shortest path connecting them, excluding internal vertices of the set. Originally motivated by some challenges in Computer Science related to robot navigation, the problem seeks to ensure unobstructed communication channels between navigating entities. The mutual-visibility problem involves determining a largest mutual-visibility set in a graph. The mutual-visibility number of a graph represents the cardinality of the largest mutual-visibility set. This concept has sparked significant research interest, leading to connections with classical combinatorial problems like the Zarankiewicz problem and Turán-type problems. In this paper, we consider practical limitations in network visibility and our investigation extends the original concept to k-distance mutual-visibility. In this case, a pair of vertices is considered S-visible if a shortest path of length at most k exists, excluding internal vertices belonging to the set S. The k-distance mutual-visibility number represents the cardinality of a largest k-distance mutual-visibility set. We initiate the study of this new graph parameter. We prove that the associate decision problem belongs to the NP-complete class. We also give some properties and tight bounds, as well as, the exact value of such parameter for some particular non trivial graph classes
From Sand to Bell: Novel Predation of Scyphozoans by the Giant Caribbean Sea Anemone Condylactis gigantea (Weinland, 1860) from the Western Atlantic
Get PDFPredation is a fundamental ecological process that shapes marine ecosystem dynamics. This study reveals a novel predator–prey interaction between the giant Caribbean sea anemone Condylactis gigantea and the two jellyfish species Cassiopea sp. and Aurelia sp., challenging traditional understanding of sea anemone feeding habits. Observations from citizen science platforms and field recordings documented C. gigantea successfully capturing and consuming these gelatinous marine organisms. The research highlights the trophic plasticity of C. gigantea, demonstrating its ability to prey on larger gelatinous organisms beyond its traditionally known diet. This predation event represents a possible benthic–pelagic coupling mechanism and underscores the value of citizen science in capturing rare ecological interactions
Sistemas de Gobierno del Buque, Capítulo 9. El Timón
No full textEstas transparencias corresponden al video del mismo nombre, publicado en Youtube, dentro de la página del Grupo Señales, Sistemas y Comunicaciones Navales de la UCAEstas transparencias corresponden al video del mismo nombre, publicado en Youtube, dentro de la página del Grupo Señales, Sistemas y Comunicaciones Navales de la UC
Sistemas de Gobierno del Buque. Capítulo 11. La Maniobrabilidad del Buque
No full textEn esta obra se reproducen las transparencias del video del mismo nombre, depositado en Youtube y realizado por el Grupo Señales, Sistemas y Comunicaciones Navales de la UCA.En esta obra se reproducen las transparencias del video del mismo nombre, depositado en Youtube y realizado por el Grupo Señales, Sistemas y Comunicaciones Navales de la UCA
Green Gaming: Automated Energy Consumption Reduction for Doom Engine
No full textThe video games industry dominates the entertainment market, standing among one of the most significant sectors in the world. Its continuous and rapid growth, driven by both the expanding player base and the increasing complexity of modern games, has significantly increased global energy consumption, estimated between 230 TWh and 347 TWh annually. The application of generic optimizations when compiling games leads to inefficient performance and unnecessary energy use. Consequently, this work presents a novel method for reducing video games energy consumption by tailoring software optimizations for the specific underlying hardware architecture. This is defined as a combinatorial optimization problem, formulated as finding the optimal sequence of LLVM code transformations that modify the considered game into an optimized version with minimum energy use. A cellular genetic algorithm is employed to optimize Doom Legacy —a modern adaptation of the original Doom engine— running on a Raspberry Pi 4. Greener versions of the software were found, compared to the performance of the popular -O3 compilation flag (the most aggressive generic LLVM optimization), achieving 26 times lower consumption values. This significant improvement results in dozens of joules saved for one hour gameplay, enhancing energy efficiency in consumer electronics as mobile devices and gaming platforms, positively impacting battery life and greenness performance
Efectividad de una intervención multicomponente para promover la actividad física durante la jornada escolar: justificación y métodos del estudio MOVESCHOOL
No full textBackground: Increasing levels of physical activity (PA) and reducing sedentary time among adolescents during the school day is a pressing need. Emerging methodologies and strategies been shown to be effective in increasing PA levels and providing additional benefits for students, such us physically active lessons (PAL), active breaks (AB) and active recesses (AR). However, evidence concerning adolescents remains limited. This manuscript presents the methods and rationale of the MOVESCHOOL study, which aims was to examine the effects of a multicomponent school-based intervention during the school day on indicators of PA, sedentary time, health, executive functions and education in adolescents.
Methods: A quasi-experimental study was conducted with the aim to involve a total of 800 students aged 12–14 years old from 11 schools (7th and 8th grade) in south-western Spain, five schools forming the intervention group and six schools forming the control group. The evaluation included two independent measurements: pre-intervention and post-intervention. The interventio n lasted 29 weeks and consisted of a multi-component programme including a weekly PAL, two 5 min daily AB, and a daily AR. Primary outcomes included accelerometer based PA and sedentary time, health-related physical fitness, academic indicators, and executive functions. For statistical analyses, descriptive, correlational, regression, and repeated measures ANOVA analyses will be applied. Additionally, qualitative data were gathered through semi-structured individual interviews and focus groups, and information will be evaluated with thematic analysis.
Discussion: The MOVESCHOOL study represents a pioneering effort in Spain, being the first of its kind to evaluate the effectiveness of a multicomponent programme in secondary schools. Furthermore, this project provides valuable insights into the effects of a multicomponent school-based PA intervention on PA levels, sedentary time, health-related, cognitive, academic indicators and psychological health markers in secondary school students. The results of this study will make a significant contribution to the educational community, providing them with innovative teaching methods and strategies that have the potential to increase PA levels during the school day. In addition, this research promises to provide a transformative experience for educators, equipping them with tools to promote the holistic development of their students, enriching their academic performance and enhancing their well-being.
Clinical trial registration: ClinicalTrials.gov, identifier NCT06254638