Search Results (2,752)

Coronary artery vasospasm (CAV) is a transient, reversible constriction of the epicardial coronary arteries that reduces coronary blood flow and may cause myocardial ischemia. Despite its clinical significance, CAV remains underdiagnosed and can present as chest pain, acute coronary syndrome, malignant arrhythmias or sudden cardiac death. Vasospasm may occur in both angiographically normal coronary arteries and at sites of pre-existing atherosclerotic stenosis. The pathophysiology of CAV is multifactorial and involves vascular smooth muscle cells (VSMCs) hyperreactivity, endothelial dysfunction, chronic inflammation and autonomic dysregulation. VSMCs contraction is mediated by phosphorylation of the myosin light chain (MLC) through calcium (Ca²⁺)/calmodulin-dependent myosin light chain kinase (MLCK), while relaxation is regulated by myosin light chain phosphatase (MLCP). Increased intracellular Ca²⁺ levels and enhanced Ca²⁺ sensitivity contribute to excessive vasoconstriction. Rho-kinase (ROCK) plays a pivotal role in sustained vasospasm by inhibiting MLCP, thereby promoting prolonged smooth muscle contraction. Endothelial dysfunction contributes to CAV by disrupting normal vascular tone regulation, largely as a result of decreased nitric oxide (NO) mediated vasodilation. Chronic low-grade inflammation and oxidative stress exacerbate both endothelial dysfunction and VSMCs contraction. Understanding these molecular mechanisms is essential for identifying novel therapeutic targets. Emerging treatment strategies, including ROCK inhibitors, endothelin receptor antagonists and anti-inflammatory agents, may improve outcomes in patients with refractory CAV. Full article

Groundwater level mapping is used in order to detect aquifer locations, flow paths, recharge zones, and contamination/pollution of groundwater. This is crucial for water management, environmental studies and resource planning focusing on landfills. This study involves the collection of monitoring well data and the mapping of the groundwater table at the Mavrorachi landfill site using Geographic Information Systems (GISs). The monitoring period spans from 2008 (startup) to 2025 (the current full year) for the 11 monitoring boreholes. Interpolation methods in GISs enabled us to map the groundwater level, while spatial analysis tools modeled the potential groundwater flow. The above process proved to be a valuable tool for modeling groundwater resources. The monitoring of groundwater level is essential to prevent the impact of leachate generated from landfill. Full article

This quantitative study exαmines the pivotal role of electronic communication (EC) and public relations (PR) within secondary education institutions. In an era of rapid digital transformation, educational organizations increasingly integrate modern communication practices to enhance transparency, collaboration, and active engagement within the school community. The research, based on a quantitative analysis of 196 educators and administrators, investigates perceptions regarding the frequency and effectiveness of digital tools using descriptive statistics, correlation analysis, and regression modeling. Key findings reveal a universal adoption of EC, with 72.96% of participants reporting daily use and 75.51% evaluating its effectiveness as high. Advanced statistical analysis through Multiple Linear Regression (R² = 0.538, p < 0.001) indicates that perceived effectiveness and frequency of use are the primary predictors of overall satisfaction. However, the study identifies significant institutional gaps, such as the absence of an official electronic communication protocol for crisis management (59.69%) and heightened concerns regarding data breaches (82.65%). The study concludes that there is an urgent need to establish unified communication strategies and provide continuous staff training in digital security and ethics. Full article

In this study, we investigate the optimization of ring spinning parameters affecting key yarn quality characteristics, including yarn tension, cop diameter, and end breakage. Experiments were conducted on cotton–polyester yarn using three process variables: traveler mass (60, 67.5, and 75 mg), spindle speed (12,900, 13,300, and 13,700 min⁻¹), and doff stage (43, 111, and 179 mm). A two-stage optimization method was applied: we used the Taguchi method to optimize individual responses, while a normalization-based composite scoring approach was used to integrate them to determine globally optimal ring spinning parameters under differing response-specific conditions. The results show that traveler mass is the dominant factor influencing yarn tension, contributing 65.48% and 73.29% of variation at the bottom and top ring rail positions, respectively. Cop diameter is primarily governed by doff stage, contributing 89.43% of total variance (ANOVA), with the intermediate level (111 mm) yielding the highest mean diameter and the most favorable S/N ratio. The yarn breakage rate is mainly affected by doff stage (57.26%) and spindle speed (41.89%), with minimum breakage observed at moderate spindle speed and mid-level doff stage. The global optimal parameter combination (60 mg traveler mass, 12,900 min⁻¹ spindle speed, and 111 mm doff stage) achieved balanced multi-response performance. The framework demonstrates strong predictive capability (R² > 0.991) and enables optimization. Full article

The taxonomy of the East Mediterranean species of the Crematogaster scutellaris complex, Crematogaster schmidti (Mayr, 1853) and C. ionia Forel, 1911 sensu lato, has not yet been investigated via modern approaches like morphometric analyses. We collected morphometric data of 201 workers from 68 nests of Crematogaster schmidti and C. ionia s. l. from Slovenia, Croatia, Montenegro, North Macedonia, the Greek mainland, Crete, Bulgaria, Samos, Karpathos, Rhodes, Turkish Thrace, and Anatolia. Nest-centroid clustering suggested four distinct entities with different geographic distributions: C. schmidti from Slovenia southwards to Greece and Turkish Thrace, and three species which have been so far summarized under C. ionia: one from the Greek mainland and North Macedonia, one from Crete, and one from Samos, Karpathos, Rhodes, and Anatolia. We describe two new species: the Cretan entity as Crematogaster ariadnae sp. n. and the Balkan mainland entity as Crematogaster graeca sp. n. A key and (re)descriptions for the East Mediterranean members of the Crematogaster scutellaris complex are provided. The four species show different geographic distribution patterns, do not occur together at the same localities, and most likely speciated through long-term geographic isolation. Full article

The valorization of agri-food by-products represents a key strategy for improving sustainability and promoting circular economy principles in food systems. Pumpkin seed press cake is a protein-rich by-product with potential application in bakery products. The aim of this study was to evaluate the feasibility of using defatted pumpkin seed press cake flour (PPSF) as a major ingredient in cookie formulations and to optimize its incorporation in order to maximize nutritional quality and sensory acceptability. Chemical characterization showed that PPSF has a superior nutritional profile compared to wheat flour, containing 55.75% protein, 8.78% minerals, and 6.15% total dietary fiber, along with significantly higher levels of total phenolics, total carotenoids, and β-carotene (0.26 mg/100 g). Formulation optimization using response surface methodology (RSM) enabled a high inclusion level of 69.61% PPSF, with 41.32% sugar and a baking time of 9 min and 29 s. The developed predictive models for diameter, thickness, overall acceptability, and bending stiffness were highly significant (p < 0.05) with a non-significant lack of fit (p > 0.05), confirming their statistical reliability for exploring the design space. The optimized C-PPSF (defatted pumpkin seed press cake flour) cookies showed a significant nutritional improvement, with protein content increasing from 13.05% to 30.17% and antioxidant capacity (DPPH) rising from 2.90% to 7.10%. While the enriched cookies had a darker color (L* 51.98) and reduced snapping force (39.7 N) due to gluten dilution, they maintained stable geometric parameters and achieved higher sensory scores for aroma, taste, and overall acceptability compared to the control. The main finding of this study is that PPSF can replace a substantial proportion of wheat flour in cookies while maintaining consumer acceptability and significantly improving nutritional quality. The optimized formulation with approximately 70% PPSF shows that this by-product has the potential to serve as a major ingredient in bakery products rather than only as a nutritional supplement. These results confirm that PPSF is a powerful functional ingredient that supports zero-waste manufacturing and provides a foundation for its broader use in bakery formulations within circular economy approaches. Future research should focus on shelf-life stability, bioaccessibility of bioactive compounds, volatile aroma profiling (e.g., GC–MS analysis), and industrial-scale validation of PPSF-based formulations. Full article

Background and Objectives: Quality of life (QoL) is an important issue for breast cancer (BC) survivors. The objective of this study was to assess health-related QoL (HRQoL) of BC patients and investigate the impact of different demographic and clinical factors on physical and social functioning and BC-related symptoms. Materials and Methods: In this cross-sectional study, 107 BC patients undergoing chemotherapy in Greece completed a questionnaire collecting sociodemographic and clinical information and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire–Core 30 (EORTC QLQ-C30) in order to assess HRQoL. Descriptive statistics and multiple linear regression analyses were used to identify factors linked to HRQoL outcomes. Results: Overall, participants reported moderate HRQoL, with high physical and social functioning and moderate emotional, cognitive, and role functioning. Fatigue was the most common symptom, whereas other symptoms were generally uncommon. Multiple regression analyses showed that marital status, place of residence, time since diagnosis, and type of surgery were significantly associated with the global QLQ-C30 score (R² = 0.337, p < 0.001). Physical functioning was associated with comorbidity burden, time since diagnosis, and employment status (R² = 0.155, p = 0.035), and social functioning with marital status and type of surgery (R² = 0.171, p = 0.011). Emotional functioning showed exploratory associations with place of residence and type of surgery; however, the overall regression model for emotional functioning did not reach statistical significance. No symptom model reached overall significance, but time since diagnosis, treatment type, and surgery were linked to distinct symptoms. Conclusions: BC patients undergoing chemotherapy in Greece report an overall moderate level of HRQoL, which is significantly influenced by a combination of demographic and clinical factors; physical and social functioning were high, with moderate emotional, cognitive, and role functioning. These findings highlight the importance of individualized supportive care strategies in order to improve QoL of BC patients. Full article

Operational labor shortages have become a pressing challenge for hospitality organizations, especially in highly seasonal tourism destinations such as Greece, where service experiences are deeply tied to cultural identity and authentic hospitality. While much of the existing research has examined understaffing from operational or human resource management perspectives, limited attention has been paid to its impact on the organizational capacity to sustain authentic hospitality experiences. Using Service-Dominant Logic (SDL) as an interpretive framework, this study views authentic hospitality as an organizational process shaped by employee interaction, cultural transmission, and service delivery practices. Drawing on survey data from 201 hotel employees in Greece, it investigates the relationship between operational labor shortages, organizational pressures, and perceived threats to authentic hospitality within hotel operations. The findings reveal significant positive relationships between work stress and service quality decline, as well as between cultural knowledge and perceived challenges in maintaining authentic hospitality. Multiple regression analysis further shows that reactive hiring, serious understaffing, and payroll cost pressure are significantly linked to perceived challenges in sustaining authentic hospitality, while service quality decline exhibits a positive but statistically non-significant effect in the final model. The study contributes to hospitality authenticity literature by emphasizing employee perceptions of authenticity as an organizationally supported process rather than merely a guest-centered outcome. The results also highlight the importance of workforce planning, recruitment quality, and cultural onboarding in supporting authentic hospitality within Greek hotel operations. Full article

Global demand for sustainability drives interest in bioenergy from sustainable feedstock. Agro-industrial waste such as brewer’s spent grains (BSG) is an important by-product of brewing. This study provides a comprehensive review of the current technologies of BSG for energy recovery and BSG-based materials for energy storage applications. The latest scientific progress, not only from conventional processes on anaerobic digestion, combustion, gasification, pyrolysis, torrefaction, and hydrothermal liquefaction but also from several integrated technologies, pretreatment methods, and additives/catalysts regarding the improvement of energy efficiency and process sustainability, was reviewed. In addition, the co-feedstock practices (co-combustion, anaerobic co-digestion, hydrothermal co-liquefaction, anaerobic co-fermentation) and co-production were examined. AD of BSG yields about 302 NL CH₄/kg COD, generating roughly 0.39 kWh of electricity/kg BSG and 1.71 MJ of thermal energy/kg BSG. Ultrasonic pretreatment enhances methane production up to four times (107 L CH₄/kg TVS) and reduces CO₂ emissions by 0.083 t CO₂eq/t BSG. Anaerobic co-digestion of BSG with other brewery waste increased the yield up to 88 mL CH₄/g TVS, generated approx. 0.348 kWh/kg TVS electricity, and reduced emissions by 0.114 kg CO₂eq/kg TVS. Bioethanol yields can reach 72%, while biohydrogen generation was up to 5154 mL H₂/g glucose. BSG pyrolysis provides up to 71.8% bio-oil, and its calorific value is 18–25 MJ/kg. BSG-derived activated biocarbon has a notable surface area (1792 m²/g) for lithium–sulfur batteries. The assessment showed that BSG’s transformation into bioenergy and energy storage materials aligns with waste reduction and sustainable development goals. However, future research on combined alternative wastes, integrated technologies, green nanotechnology, and artificial intelligence technology could lead to optimal performance and facilitate their industrial application. Full article

Topological data analysis (TDA) has evolved into a flexible and robust paradigm for obtaining qualitative, geometry-inspired insights from high-dimensional, noisy, and complex data. Grounded in algebraic topology, geometry, statistics, and machine learning (ML), TDA provides multiscale descriptions through persistent homology, Mapper (a graph-based method that summarizes the shape of high-dimensional data), and related topological signatures that are often inaccessible to standard linear and metric methods. In recent years, and especially during 2024–2025, TDA has expanded rapidly across science, engineering, biomedical research, and socio-economic studies, while also being integrated with modern learning paradigms such as deep learning (DL) and graph learning. This survey summarizes recent developments in TDA using a carefully selected set of articles, with emphasis on 2024–2025. We first present the mathematical and computational foundations of TDA, covering simplicial complexes, filtrations, persistent homology, the Mapper algorithm, and computational advances such as data simplification, stability, and efficiency. We then review applications in time series and dynamical systems, biomedical imaging and precision medicine, engineering and physical sciences, finance and risk analysis, DL and interpretability, and security and critical infrastructure systems. Throughout, we highlight how TDA can extract informative features, function as a model component, and provide a conceptual lens for studying complex systems. However, the survey also emphasizes recurrent failure patterns: TDA performance is highly sensitive to filtration, embedding, and vectorization choices; aggressive simplification can dilute or remove informative topological signals; and integration into standard ML workflows still lacks uniform validation and reporting protocols. We conclude by outlining key challenges—including scalability, statistical foundations, interpretability, and compatibility with rapidly evolving artificial intelligence (AI) paradigms—and by identifying directions for future research. The survey also provides a unifying design perspective for TDA systems, highlighting methodological trade-offs and emerging research directions for integrating topology with modern ML. Full article

Background: In elderly patients with hypoalbuminaemia, hypoproteinaemia and advanced-stage PUs, chronic inflammation and wound-related protein loss contribute to a self-perpetuating circulus vitiosus, in which protein depletion drives deterioration of tissue repair processes, and in turn, ongoing wound-related catabolism further amplifies systemic protein loss. In this context, reduced serum albumin and total protein represent integrated indicators of systemic inflammatory and catabolic burden associated with delayed wound healing. Aim: This study evaluated the association between individualized nutritional replacement therapy and pressure ulcer healing in malnourished geriatric and palliative patients, using serum albumin, total protein, and PUSH score as longitudinal outcome indicators. Methods: A total of 78 malnourished geriatric and palliative patients with PUs, multiple comorbidities, and poor nutritional status (hypoalbuminemia and/or hypoproteinaemia) receiving patient-tailored nutritional replacement therapy participated in this study. PU assessment using the PUSH version 3.0 tool, as well as measurements of serum albumin and total protein concentrations, were performed on days 0, 30, 60, and 90. Results: Our study demonstrates significant improvement in the serum albumin levels, from 30.2 ± 6.19 at baseline to 42.1 ± 5.59 at day 90. Similarly, total protein concentrations increased from 57.8 ± 9.66 at baseline to 70.6 ± 7.03 at day 90. The improvement in protein status was accompanied by a significant reduction in the PUSH score, from 10.9 ± 2.94 at the first assessment to 2.9 ± 2.63 at the final assessment. Spearman’s rank-order correlation analysis between serum albumin, total protein, and PUSH score demonstrated a significant moderate inverse correlation at later assessment points (day 60 and 90). Conclusions: Individualized and targeted replacement therapy was associated with improved protein status and reduced pressure ulcer severity. Increases in serum albumin and total protein paralleled a marked reduction in PUSH scores, suggesting attenuation of the inflammatory-catabolic circulus vitiosus and a progressive shift toward wound healing in geriatric and palliative patients. Full article

This study presents a novel approach for the development of biofunctional and skin-comfortable cotton textiles through the integration of blackcurrant water/ethanol pomace extract into polysaccharide-based fabric coating. Extraction of bioactive compounds from blackcurrant pomace was optimized using response surface methodology, yielding a total phenolic content of 36.04 mg GAE/g DW, along with significant contents of flavonoids (5.28 mg QE/g DW) and anthocyanins (5.18 mg/g DW). The cotton fabric was biofunctionalized using the layer-by-layer (LbL) deposition technique, incorporating blackcurrant pomace extract within four, eight, or twelve chitosan/pectin bilayers. The biofunctionalized fabrics exhibited no cytotoxic effect and demonstrated nearly 100% antioxidant and antibacterial activity against E. coli and S. aureus. Additionally, the LbL coating enabled tunable extract adsorption (0.09–2.70%) and stabilization of bioactive compounds on the cotton surface, resulting in adjustable fabric coloration and moisture management properties (assessed using the Moisture Management Tester). Molecular docking analysis provided insight into the interactions between HPLC-detected anthocyanins (cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside, delphinidin-3-O-glucoside, and delphinidin-3-O-rutinoside) and polysaccharides, revealing an increase in binding affinity from cellulose to chitosan and pectin. The transition from comfort-oriented fabric to a material featuring integrated moisture management and enhanced biofunctionality, achieved by coating cotton with eight chitosan/pectin bilayers incorporating blackcurrant pomace extract, renders the textile suited for medical, protective, and high-comfort applications. Full article

Even though the functional food market has rapidly increased in recent years, the links between bioactive-rich formulations and consumers’ health benefit are not fully established, mainly because of insufficient consideration of food matrix effects. This review provides a comprehensive and integrated evaluation of how food matrix properties (structural and physicochemical) affect the bioaccessibility of plant bioactive compounds. Unlike many reviews that focus on a single nutrient approach, we highlight quantitative evidence of how bioaccessibility can be affected by matrix properties, illustrating the interactions between main food components (lipids, proteins, dietary fiber and minerals). This review integrates fragmented information among different areas of food and nutrition sciences, i.e., food structure, gastrointestinal science, mineral chemistry, protein chemistry, providing a holistic framework for Quality by Design (QbD) functional food development. Synergisms and antagonistic behaviors, threshold effects, and concentration-dependent behaviors are analyzed comparatively for the most common plant-derived bioactives, such as polyphenols, carotenoids, curcuminoids and minerals (iron, zinc and calcium). We propose a matrix-informed optimization as a prerequisite for credible health claims and sustainable plant-based nutrition strategies. This can ultimately serve as a foundation for next-generation functional food development based on bioaccessibility, supporting the central argument that functional food development should move from composition-based fortification to bioaccessibility-based matrix engineering. Full article

Path planning for autonomous robots is a key problem area, particularly when faced with complicated, dynamic, or uncertain environments. Even though traditional techniques (grid-based, graph-based, sampling, and optimization-based) have already been developed to solve this problem, there are notable limitations to scalability, adaptability, and responsiveness with these methods. In this paper, we explore an alternative approach based on chaotic dynamical systems, specifically chaotic attractors like those produced by the Lorenz and Rössler systems. Chaotic systems are defined by several properties that could be leveraged: non-linearity, sensitivity to initial conditions, and dense coverage of the state space are three notable properties that could be used to generate trajectories that are organized, yet ultimately unpredictable. By applying numerical integration (Runge–Kutta) directly to robot motion through MATLAB R2025b simulations, chaotic states support more effective exploration, better obstacle avoidance, and more robust navigation in dynamic or adversarial environments. The paper also examines whether chaotic path planning can be applied in multi-robot systems through state coupled robots that emerge coordinated behavior while maintaining autonomous movement. This paper is a framework for chaos theory supporting adaptable, robust navigating behaviors for purposes such as autonomous vehicles, swarm robotics, and search and rescue and surveillance applications. Full article

Heraclitus’ phrase “everything flows and nothing remains” perfectly captures the modern era, as conditions are changing at high speed and scientific knowledge is growing exponentially. Academic fields that attract significant attention often experience rapid expansion, driven by the growing global pool of researchers, the increased accessibility of scientific publishing platforms, and the overall rise in scientific output. Literature concerning energy security, a topic as old as fire, has become vital to modern economies due to geopolitical upheaval, adapting traditional considerations to new realities, and the extensive body of literature serves as clear evidence of this fact. Thus, there is a clear need for innovative, scalable, and objective methodologies to systematically assess the existing body of knowledge and prioritize areas for further study. This paper proposes implementing a novel machine learning approach leveraging the BERTopic topic modeling algorithm to conduct a comprehensive and efficient exploratory analysis of energy security literature. The analysis is based on a bibliographic corpus extracted from the Scopus database covering the period 1999–2025, and identifies 14 distinct thematic clusters which indicate that energy security research is undergoing structural transformation, marked by strong emphasis on technology-specific renewable energy transitions, geographic concentration on China and Europe, and increasing integration with climate and sustainability frameworks. While contextual embedding improves semantic coherence, topic interpretation still requires expert validation as model performance is sensitive to hyperparameter configuration, potentially affecting topic stability and reproducibility. Full article