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Multi-episodic bauxitization in a karstic and rifted setting (Early Cretaceous, South-western Iberian Basin, Spain): An interdisciplinary approach
Get PDFBauxitic deposits serve as valuable sedimentary archives, offering insights into paleoclimatic, paleogeographic, and geodynamic processes over time. A multidisciplinary analysis of bauxitic deposits in the Cuenca Domain (Iberian Ranges, central Spain) aims to reconstruct their genesis in the framework of the geological evolution of this region during the Late Jurassic-Early Cretaceous rift episode. The bauxitic deposits preserve paleosol profiles that show multi-episodic processes of sedimentation, reworking, erosion, pedogenesis, and bauxitization, reflecting a landscape's dynamics that was strongly influenced by episodic tectonic activity. The presence of book-type kaolinite aggregates, ferruginous pisoids and ooids, and soil horizons provide evidence of in situ bauxitization. On the other hand, the presence of fractured pisoids and ooids, brecciated textures, and bauxitic C horizons also points to some degree of reworking. Authigenic boehmite suggests optimal conditions for bauxitization, whereas ferruginous crusts and peds at the top of the deposits point to a later ferruginization phase. A subsequent kaolinitization episode, probably driven by the infiltration of silica-rich fluids, is also recorded. By integrating stratigraphic, sedimentological, and mineralogical data, a succession of genetic stages in bauxite development has been identified, shaped by the tectonic evolution of the area. The proposed stratigraphic and pedogenetic model enhances the regional significance of the findings and enables a refined chronology of its tectonic evolution. The results highlight the potential of bauxitic materials, not only as paleoclimatic indicators but also as robust tools for reconstructing paleogeographic and tectonic conditions in complex settings where the sedimentary record is apparently homogeneous and extremely incomplete
Exploring consumer label preferences for fresh vegetables in Aragon: insights for market differentiation
Get PDFThis study determines which labels should be used to differentiate vegetables cultivated in Aragon in the local market, according to consumer preferences. The aim is to analyse the importance consumers attach when buying fresh vegetables to different labels commonly used to market these products. The labels analysed were “Organic”, “Protected Designation of Origin (PDO)”, “C’Alial regional brand”, “Km0”, “Local sales”, “Local variety”, and “Collective producer brand”. A Best-Worst method, in which the respondents must indicate which label is the most and least important, was used. Data was gathered using an online survey of vegetable consumers in Aragon. The sample was stratified by age, gender, and province of residence. Label importance for consumers was assumed to be heterogeneous, and a Latent Class (LC) model was estimated. Results indicate that the most important labels were “Local sales”, followed by “Km0”, “Local variety”, “PDO” and “Organic”. The least valued labels were “C’Alial” and “Collective producer brand”. Therefore, according to the obtained results, producers should focus on proximity markets using local varieties. Consumers’ heterogeneity in the importance they attached to different labels was found. Four classes of consumers were detected and explained by socio-demographic characteristics, the importance of vegetable attributes, the frequency of vegetable consumption, the knowledge of the method of production, and the attitudes and intention to purchase vegetables from local landraces. Accordingly, different strategies should be used to attract different consumers
Quadratic unconstrained binary optimization for environmental control system equipment design and assessment
Get PDFThis paper explores possible implementations of a quantum annealing-based algorithm, in the Quadratic unconstrained binary optimization method (QUBO) form, to solve the thermo-fluid dynamics problem associated with the design of critical components of aircraft environmental control systems, namely compact heat exchangers and ejectors (also known as jet pumps), used on rotary- or fixed- winged aircrafts environmental control system to mix two fluids and exchange thermal energy. The purpose of this paper is to introduce the implementation of the QUBO model based on compact heat exchangers lumped model and the SAE 1168–6 ejector design procedure, with the formalization of the mathematical problem and the comparison of results obtained with experimental tests, classical resolution approaches and the quantum optimized code, showing how the QUBO approach is an effective and efficient tools for design engineers tasked to design and validate equipment parameters.We start with a simple two-phase flow within a single-pass mini-channel heat exchanger, describing the mathematical formulation of the problem followed by a simplified implementation of the proposed quantum approaches, highlighting the main procedures of the calculation as well as the practical implications, advantages and disadvantages of the proposed method, e.g. a limited number of CFD simulations are required to evaluate air side heat transfer coefficient and pressure drop for particular designs within the defined design space, and the specific hardware required to implement the quantum process
Exploring genomic diversity and reproductive strategies in three expansion phases of the superdominant Brachypodium rupestre in high mountain grasslands
Get PDFTall-grass expansion in natural plant communities is a concern under current global change scenarios. Driven by factors such as community vulnerability and the competitive abilities of tall-grass species, this phenomenon is exemplified by Brachypodium rupestre (Host) Roem. and Schult, a perennial tall-grass native to Europe. B. rupestre spreads aggressively in the grasslands of the western Pyrenees due to a disrupted regime of lack of herbivory and recurrent burnings that has persisted over several decades. This study aims to investigate whether the contrasted managements of grazing, abandonment and burnings have promoted specific reproductive traits and impacted the population genomics of B. rupestre. Nine sites varying in cover of B. rupestre classified into three expansion phases associated to different management regimes were monitored: (i) scattered populations in multispecific grazed sites, (ii) stand populations expanding at sites of relaxed grazing or abandonment, and (iii) superdominant populations constituting dense degraded covers in recurrently burned sites. ddRADseq data showed high genomic diversity but relatively low genomic structure, likely due to substantial gene flow and the absence of wind barriers. The standardized index of association supported asexual reproduction in all populations, which is coupled with sexual reproduction. Contrasting management practices did not promote distinct genomic identities between expansion phases; rather, the genetic differentiation and divergence of populations responded to life history and spatial isolation, even within a small geographic area. The similar levels of genetic diversity and the significantly different number of clones between expansion phases suggest a complex pattern of genotypic and clonal variability, which may be influenced by environmental factors (historical disturbance regimes)
Circadian rhythm of locomotor activity and body temperature in free-range laying hens as measured by triaxial accelerometers and subcutaneous biologgers
Get PDFBiosensors are essential tools for monitoring temperature in poultry because they provide real-time data that can enhance animal welfare and productivity. The aim of this study was to evaluate the use of triaxial accelerometers and subcutaneous biologgers to monitor of locomotor activity (LA) and body temperature (BT) in free-range laying hens, to explore their potential for assessing circadian patterns relevant to welfare monitoring. Five hens were fitted with a harness that carried an accelerometer to record LA for 6 d. In addition, hens received a surgically implanted biologger to record BT every 15 min. Animals were housed indoors that had an artificial photoperiod (16L:8D) and an adjacent outdoor pen. Hen BT decreased between 1900 h and 2300 h, and was lowest 30 min before lights turned off at 2330 h. From that moment, BT increased throughout the night and until 0900 h in the morning; after which, it remained stable until the evening. Animals remained practically motionless during darkness, and began moving immediately after lights turned on. BT and LA exhibited a 24-h circadian rhythm. There was a significant correlation between BT and LA (P < 0.01), but BT was not correlated with ambient T. LA was correlated with indoor and outdoor ambient T (P < 0.01). In conclusion, free-range laying hens exhibited clear circadian rhythms in LA and BT, which were synchronized with the light-dark cycle. Ambient T influenced LA, which was correlated with BT. Those findings can contribute to the optimization of management practices that are intended to maximize welfare and productivity
Patios sonoros: intervención artístico-educativa para la cohesión social y el desarrollo de competencias transversales en un centro educativo especial
Get PDFEl presente artículo investiga sobre una experiencia artístico-educativa denominada “Patios Sonoros” en una escuela pública con necesidades educativas especiales (comunidad anonimizada). El proyecto se fundamenta en la necesidad de mejorar la cohesión social, el respeto, la creatividad, el aprendizaje y la motivación del alumnado en un centro marcado por la diversidad cultural y dificultades de convivencia. Este trabajo busca conocer qué posibilidades ofrece el proyecto “Patios Sonoros” para la formación de competencias artísticas y transversales en el alumnado y en qué medida este tipo de enfoques interdisciplinares promueven una transformación en la escuela. Para ello se adoptan métodos de investigación cualitativa (análisis documental, observación, entrevistas) bajo el enfoque de investigación-acción. El proceso creativo de la instalación contó con tres fases de búsqueda y preparación de los materiales artístico-sonoros; montaje de las instalaciones en los espacios seleccionados previamente y exploración de los materiales y de sus posibilidades sonoras, sensoriales y artísticas. Los resultados muestran que el desarrollo de instalaciones artísticas hace converger disímiles aprendizajes, actitudes colaborativas, creativas, de emprendimiento y una alta motivación de los participantes que comprometen, desde el punto de vista estético y social, la transformación del espacio y la comunidad educativa.
This article examines an artistic-educational experience called ‘Sound Courtyards’ in a public school with special educational needs in the Autonomous Community of Castilla y León. The project is based on the need to improve social cohesion, respect, creativity, learning and student motivation in a school marked by cultural diversity and difficulties of coexistence. This work seeks to find out what possibilities the ‘Sound Courtyards’ project offers for the formation of artistic and transversal competences in pupils and to what extent this type of interdisciplinary approach promotes a transformation in the school. For this purpose, qualitative research methods (documentary analysis, observation, interviews) were adopted under the action-research approach. The creative process of the installation consisted of three phases: research and preparation of the sound-artistic materials; installation of the installations in the previously selected spaces; and exploration of the materials and their sound, sensory and artistic possibilities. The results show that the development of artistic installations brings together different types of learning, collaborative, creative and entrepreneurial attitudes and a high level of motivation among the participants, who commit themselves, from an aesthetic and social point of view, to the transformation of the space and the educational community.Keywords: art installations; sound courtyards; transversal competencies; music education; action research
Dementia Prevalence in the CARhES Cohort: Importance of Socioeconomic Level
Get PDFObjectives: Dementia preventive strategies might benefit from a comprehensive approach that considers the interplay of biological and social factors. The aim of this study was to examine the prevalence of dementia by sex and age in a cohort of individuals with cardiovascular risk factors, and to assess how sociodemographic and clinical factors are associated with this disease. Methods: Cross-sectional study was conducted on ≥55-year-old individuals from the CARhES (CArdiovascular Risk factors for HEalth Services research) Spanish cohort. Real-world data on sociodemographic, clinical, and drug information was obtained. Dementia cases were identified by diagnoses and pharmacological treatment. Age- and sex-stratified logistic regression models and sex-stratified CTree analyses were used. Results: The prevalence of dementia among the 323,973 individuals in the cohort was 5.2%, 3.4% in men and 6.6% in women, and it increased with age. In both sex groups, stroke and depression were associated with a higher prevalence of dementia for all the age groups, while sex differences were found in the association of the rest of the sociodemographic and clinical variables with dementia. Being older and with lower socioeconomic status were the most predictive factors of dementia prevalence. Stroke was a stronger indicator in men than in women, while hypertension was nearly twice as significant in women. Conclusions: The prevalence of dementia in people with cardiovascular risk factors was 5.2%, similar to that of the general population. Besides age, having a lower socioeconomic level was the most important indicator of dementia, which may justify more resources and care for these populations
New dwarf crocodylomorph from the Upper Jurassic of Portugal and the first neuroanatomical data for Atoposauridae
Get PDFA new crocodylomorph fossil specimen (ML2631) from the Upper Jurassic of Lourinhã (Portugal) is described, based on a partially preserved skull table and braincase. The specimen was recovered from the Zimbral vertebrate microfossil assemblage, located in the lower part of the Praia Azul Member of the Lourinhã Formation (Kimmeridgian–Tithonian transition). The fossil was scanned using high-resolution micro-computed tomography (µCT), enabling the digital reconstruction of internal cranial structures, such as the brain cavity, cranial nerves, inner ear and paratympanic sinus system. These reconstructions represent the first neuroanatomical data ever reported for Atoposauridae, a clade of small-bodied neosuchian crocodylomorphs common in the Late Jurassic and Cretaceous of Europe.
Phylogenetic analysis places ML2631 within Atoposauridae and contributes to resolving previously uncertain relationships within the group. Although fragmentary, ML2631 exhibits a unique combination of anatomical features, including a dorsolaterally open cranioquadrate passage, a sagittal crest along the frontal and parietal, a large, posteriorly placed and septate choana, large supratemporal fenestrae with a distinct posterior fossa and a squamosal lobe bearing a discontinuous lateral groove. These traits, amongst others, distinguish ML2631 from all other known atoposaurid species. Additionally, its neuroanatomical proportions suggest a dwarf adult individual with low-frequency auditory sensitivity and moderate visual acuity, consistent with a primarily terrestrial or nearshore lifestyle, coherent with the depositional environment of the fossil site. Taken together, these results highlight the taxonomic and evolutionary relevance of the specimen and underline the importance of future discoveries of more complete material to confirm its systematic and phylogenetic status within Atoposauridae
A viable but nonculturable state of Mycobacterium avium in response to macrolide antibiotics: a recipe for relapses?
Get PDFMycobacterium avium complex disease is difficult to treat, with high failure and recurrence rates despite multidrug, macrolide-based treatments. The bacterial mechanisms involved in this drug tolerance and persistence are incompletely understood. Recent evidence has suggested persistence through metabolic adaptations indicative of the viable but nonculturable state, including a decreased respiratory rate and a switch to lipid accumulation and metabolism. To assess the contribution of switching to viable but nonculturable state to macrolide tolerance, we performed time–kill kinetics assays for clarithromycin against M. avium. In these experiments, we performed Auramine-O (for acid-fastness, representing active mycobacteria) and Nile red (for lipid accumulation) staining and stimulation using resuscitation-promoting factors of Mycobacterium tuberculosis. Loss of auramine staining, increased Nile red staining and increased population sizes after stimulation with resuscitation-promoting factors support the hypothesis that clarithromycin induces a viable but nonculturable state in M. avium. Induction of a viable but nonculturable state is one of the mechanisms of macrolide tolerance in M. avium. It might be one of the drivers of the high failure and recurrence rates of macrolide-based treatments. Antimicrobials active against viable but nonculturable M. avium may improve treatment outcomes
Magnetization Losses and Non-Reduced 3D Modeling of Hybrid CORC-TSTC Composite Conductors
Get PDFThe Conductor on Round Core (CORC) and Twisted Stacked-Tape Conductor (TSTC) are among the most promising architectures for high-temperature superconducting (HTS) cables due to their high current-carrying capabilities, essential for future fusion and high voltage -high current- power applications. While CORC designs offer mechanical robustness, their larger cross-sections can lead to spatial inefficiencies, whereas TSTC cables are more compact but limited in transport current. To bridge these trade-offs, a CORC–TSTC hybrid cable has been recently proposed by Korean researchers, though its electromagnetic performance remains largely unverified. In this work, we present a comprehensive three-dimensional electromagnetic study to validate the experimentally measured AC losses of such hybrid cables, using SuNAM Co. Ltd. GdBCO HTS tapes. Our model captures the full current dynamics on the surface and within the superconducting layers, overcoming the limitations of reduced-order gauge (2D) methods. The hybrid cable configurations considered consist of a six-tape CORC outer layer enclosing a TSTC core with one to four stacked tapes. The model incorporates magneto-angular anisotropy in the critical current density, informed by experimental data, to ensure accurate benchmarking. To contextualize the hybrid design’s performance, we also simulate two reference geometries: a single-layer and a double-layer CORC cable, as well as a ten-tape TSTC conductor. Results show that the hybrid configuration offers a compelling balance, combining low AC losses with compact geometry and structural flexibility