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Novel Glue-Stabilized Sorbent Layers for Adsorption Chillers: Thermal and Sorption Characteristics
No full textAdsorption chillers can produce chilled and desalinated water using low-grade heat, but their performance is limited by low coefficient of performance (COP) and large system mass. Enhancing heat and mass transfer in the sorbent bed is key to improving efficiency. This work introduces and systematically evaluates binder-stabilized silica gel composites as a structural and thermal enhancement strategy for adsorption chillers. Silica gel composites bonded with epoxy resin and polyvinyl alcohol (PVA) were evaluated for adsorption chiller applications. Thermal stability, conductivity, microstructure, equilibrium sorption, and sorption hysteresis were assessed. The results indicate that PVA-based composites were thermally unstable and discarded, whereas epoxy-bonded silica gel showed high thermal stability and mechanically robust granules with preserved pore connectivity. The epoxy composite exhibited 109% higher thermal conductivity than loose silica gel, improving internal heat transfer. This improvement is accompanied by a reduction in sorption capacity of approximately 58%, attributable to the inert resin fraction. Notably, the composite exhibits a reduced and locally negative sorption hysteresis, indicating facilitated desorption and lowered internal diffusion resistance. The epoxy-bonded silica gel therefore provides a promising combination of thermal stability, improved heat transfer, and enhanced sorption–desorption behaviour, supporting its potential to increase the efficiency of next-generation adsorption chillers
Variability and Number of Circulating csd Alleles in a Honey Bee Breeding Population After Four Years of Single-Drone Insemination
No full textBackground: Varroa destructor is the major threat to honey bee health, and selective breeding for resistance traits such as Varroa-sensitive hygiene represents a promising long-term strategy for controlling mite populations. However, breeding programs that rely on highly controlled mating schemes, including single-drone instrumental insemination, may reduce allelic diversity at the complementary sex determiner (csd) locus, potentially increasing the production of non-viable diploid males and compromising colony fitness. Methods: To evaluate whether csd diversity can be maintained under these conditions, we characterized the hypervariable region of csd in a selectively bred Apis mellifera population subjected to four years of selection. Using a validated de novo assembly pipeline, we reconstructed 43 amino-acid sequences from 33 diploid worker pupae sampled across 13 colonies. Results: Seven distinct alleles were identified, five of which were shared among multiple colonies and corresponded to variants already described in the literature, while two were private to individual colonies and novel in the literature. Colony-level frequency data revealed a moderate diversity: the most common allele was detected in nine colonies, with an allelic frequency of 31%. Moreover, the expected heterozygosity of the population was estimated at 0.79. Conclusions: Overall, these findings show that csd diversity can be partially maintained even under strong selective pressure when multiple maternal lines are retained, and they underscore the importance of incorporating genetic information into breeding decisions to support the long-term sustainability of selective breeding programs
Feasibility of Conditional Tabular Generative Adversarial Networks for Ecologically Plausible Synthetic River Water-Quality Data: A Statistical and Ecological Similarity Assessment
No full textReliable biological datasets, especially those integrating biotic indices such as the Saprobic Index, are scarce, limiting machine and deep learning applications in aquatic ecosystem assessments. This study evaluates Conditional Tabular Generative Adversarial Networks (CTGANs) for generating synthetic datasets that combine physico-chemical parameters with a biological index (Saprobic Index) from multiple monitoring stations in the lower Danube River. Beyond univariate distributional agreement, we assess whether ecologically meaningful multivariate relationships are preserved in the synthetic tables. To support this, we propose an ecology-oriented validation workflow that combines distributional tests with correlation structure and clustering diagnostics across stations. Real monitoring datasets were statistically modelled and recreated using CTGANs, then qualitatively assessed for realism. Comparisons between synthetic and real data employed box plots, Wilcoxon rank-sum tests, correlation matrices, and K-means clustering across stations. Stable variables, including pH, total dissolved solids, and chemical oxygen demand, were well replicated, showing no significant distributional differences (p > 0.05). Conversely, dynamic parameters such as dissolved oxygen, total nitrogen, and suspended solids exhibited notable discrepancies (p < 0.05). Correlation analyses indicated that several strong associations present in the observed data (e.g., total nitrogen–nitrate and total nitrogen–electrical conductivity) were substantially weaker in the synthetic dataset. Overall, a CTGAN can reproduce several marginal patterns but may fail to preserve key ecological linkages, which constrains its use in ecological relationship-dependent inference. While promising for exploratory modelling and general trend analysis, synthetic data should be applied cautiously for studies involving seasonally influenced, biologically significant parameters
Inclusive Digital Practices in Pre-Service Teacher Training in Chile and Portugal: Design and Validation of a Scale to Assess the Social Determinants of the Digital Divide
No full textThis study examines the social determinants of the digital divide in pre-service teacher education through the design and validation of the Digital Hospitality Scale (DSBD-HD-FID). The instrument was developed to diagnose social inequalities across six key dimensions: socioeconomic status, geographic location, gender, age, disability status, and interculturality. These dimensions are understood as structural factors shaping access to, use of, and participation in digital environments within teacher education. The research followed a non-experimental, quantitative, and cross-sectional design, including content validation through expert judgment and statistical analysis based on a pilot sample of education students from Chile and Portugal. An exploratory factor analysis was conducted, and internal consistency was assessed using Cronbach’s alpha coefficient. The results confirm strong content and construct validity, as well as high reliability (α = 0.93). Empirical findings indicate that socioeconomic status and geographic location significantly condition access to connectivity and digital literacy, while gender differences emerge mainly in recreational uses and frequency of digital training. Beyond these results, the study highlights the relevance of addressing digital inequalities in teacher education through inclusive and equity-oriented training policies. The findings support the integration of digital hospitality, human rights education, and the Sustainable Development Goals into initial teacher training curricula as measurable and evaluable dimensions, providing an evidence-based framework to inform future teacher education policies aimed at reducing digital divides and promoting social cohesion
Aortic Valve Stenosis: Progress from Diagnosis to Treatment
No full textAortic stenosis (AS) is the most prevalent valvular heart disease in Western countries and it is especially associated with older age. With its progressive course, AS leads to ventricular hypertrophy, impaired diastolic and systolic function, and symptomatic deterioration. The natural history of AS is closely linked to the extent of myocardial and extracardiac damage in association with the patients comorbidities. Diagnosis relies primarily on transthoracic echocardiography, which assesses valve morphology, quantifies stenosis severity, and evaluates cardiac remodeling. However, discordant grading is frequent, necessitating advanced imaging to clarify the severity and the mechanism of the stenosis and stratify risk. Treatment is predominantly interventional, as no medical therapy is able to stop disease progression. Surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) are the two treatment options. Special clinical scenarios—such as cardiogenic shock or concomitant cardiac amyloidosis—pose additional diagnostic and therapeutic challenges and require individualized, multidisciplinary management. Overall, contemporary AS care increasingly integrates multimodality imaging, refined risk stratification, and tailored interventional strategies to optimize outcomes
Correction: Aziz et al. Biochar and Polyhalite Fertilizers Improve Soil’s Biochemical Characteristics and Sunflower (Helianthus annuus L.) Yield. Agronomy 2023, 13, 483
No full textThere was an error in the original publication [...
Real-World Treatment Patterns and Outcomes of Intraluminal Ablative Therapies in Noninvasive Urethral Carcinoma: A National Cancer Database Analysis
No full textObjective: To evaluate treatment patterns, predictors of treatment selection, and overall survival (OS) in patients with noninvasive (Ta–Tis) urothelial carcinoma of the urethra (UUC). Patients and Methods: We conducted a retrospective cohort study of adults diagnosed with noninvasive UUC (stage Ta or Tis, N0, M0) between 2018 and 2021 using the National Cancer Database. Patients were categorized into prostatic and non-prostatic urethral cohorts. Treatment groups included endoluminal ablation alone, ablation combined with topical intraluminal therapy, urethrectomy, and no subsequent treatment. Multinomial logistic regression was used to identify predictors of treatment selection. The OS was assessed using Kaplan–Meier and multivariable Cox regression, with separate models for each anatomical cohort. Results: A total of 436 patients were included (185 non-prostatic, 251 prostatic); 91.9% (n = 401) were male. Ablation alone was the most common treatment in both cohorts (non-prostatic: 57.3%; prostatic: 62.6%), followed by urethrectomy (non-prostatic: 21.1%) and ablation plus topical therapy (prostatic: 20.3%). In the non-prostatic cohort, high-grade histology (OR 15.15; 95% CI, 3.82–60.04) and Tis stage (OR 3.27; 95% CI, 1.10–9.69) were associated with increased odds of urethrectomy. In the prostatic cohort, high-grade histology was associated with increased use of urethrectomy (OR 59.29; 95% CI, 4.61–763.17) and ablation plus topical therapy (OR 3.09; 95% CI, 1.21–7.90). Tis stage was also associated with ablation plus topical therapy (OR 2.53; 95% CI, 1.14–5.62). This treatment approach was associated with improved OS compared with ablation alone (HR 0.18; 95% CI, 0.05–0.60; p = 0.005). Conclusions: Treatment selection differed substantially by tumor location, stage, and grade, reflecting both treatment selection in noninvasive UUC varied by tumor location, grade, and stage. In prostatic tumors, ablation plus topical therapy was associated with improved survival, supporting its role as a risk-adapted, organ-sparing strategy in selected patients
Fair Division of Indivisible Items: Envy-Freeness vs. Efficiency Revisited
No full textWe study conflicts between envy-based fairness and efficiency for allocating indivisible items under additive utilities. We formalize several small, transparent instances showing that standard envy-freeness (EF) or its relaxations EFX and EFX0—i.e., envy-freeness up to any item, where EFX restricts attention to positively valued items and EFX0 allows removing zero-valued items as well—can conflict with Pareto-optimality (PO), maximin (MM), or maximum Nash welfare (MNW). Normatively, we argue that envy-freeness (even as EFX or EFX0) is not a panacea for allocating indivisible items and should be weighed against efficiency and welfare criteria
Stress-Testing Slovenian SME Resilience: A Scenario Model Calibrated on South African Evidence
No full textSmall and medium-sized enterprises (SMEs) play a central role in employment and regional economic development, yet they are highly vulnerable to shocks such as pandemics, energy price spikes, and supply chain disruptions. Scenario modelling, stress testing, and digital twins are used to assess resilience, yet most applications focus on large firms in single-country settings. This article develops a model to stress test the resilience of Slovenian SMEs, calibrated with parameters and mechanisms derived from South African SME resilience studies. A system dynamics model with stocks for cash, inventory, and productive capacity is specified and subjected to demand, supply, financial, and compound shock scenarios, with and without resilience measures such as liquidity buffers, customer and supplier diversification, and basic digital planning capabilities. Results indicate non-linear tipping points where small reductions in liquidity sharply increase the likelihood of distress, and show that combinations of liquidity, diversification, and collaborative supply chain practices reduce the depth and duration of output losses. The study demonstrates how evidence from an African context can inform resilience strategies in a small European economy and provides a transparent, portable modelling architecture that can be adapted to other settings. Implications are discussed for SME managers and for policies supporting sustainable, resilient enterprise ecosystems
Highly Efficient Software Development Using DevOps and Microservices: A Comprehensive Framework
No full textWith the growing popularity of DevOps culture among companies and the corresponding increase in Microservices architecture development—both known to boost productivity and efficiency in software development—an increasing number of organizations are aiming to integrate them. Implementing DevOps culture and best practices can be challenging, but it is increasingly important as software applications become more robust and complex, and performance is considered essential by end users. By following the Design Science Research methodology, this paper proposes an iterative framework that closely follows the recommended DevOps practices, validated with the assistance of expert interviews, for implementing DevOps practices into Microservices architecture software development, while also offering a series of tools that serve as a base guideline for anyone following this framework, in the form of a theoretical use case. Therefore, this paper provides organizations with a guideline for adapting DevOps and offers organizations already using this methodology a framework to potentially enhance their established practices