Search Results (2,701)

Two-dimensional (2D) materials exhibit electronic and collective excitation properties that are highly sensitive to surface chemistry and thickness, requiring surface-sensitive characterization at low electron energies. Here, we investigate graphene, hexagonal boron nitride (h-BN), molybdenum disulfide (MoS₂), and titanium carbide (Ti₃C₂) MXene using an advanced home-built scanning low-energy electron microscopy system combined with time-of-flight electron spectroscopy (SLEEM/ToF). The system uniquely records electron energy-loss spectra (EELS) from transmitted electrons rather than from the reflected electrons used in conventional SLEEM. Compared with high-energy EELS, our low-energy ToF-EELS approach offers enhanced surface sensitivity and reduced beam-induced damage, enabling direct probing of π and π + σ plasmon excitations. Additionally, complementary techniques, including scanning transmission electron microscopy (STEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS), were employed to characterize structural and chemical properties. EELS were acquired for all investigated 2D materials at electron landing energies of 500–1500 eV, and in the 5–50 eV range for selected materials, including graphene and MoS₂. Analysis of these spectra enabled determination of the average plasmon positions across the measured energy range for all studied materials. Furthermore, a quantitative determination of the inelastic mean free path (IMFP) was achieved for graphene in the 10–50 eV range, yielding a value of 1.9 ± 0.2 nm. These results demonstrate the potential of SLEEM–ToF for surface-sensitive analysis of 2D materials. Full article

Instructor clarity is a central component of instructional communication and has been consistently associated with positive academic outcomes; however, less evidence exists regarding the mechanisms through which it influences student interest in higher education contexts. From a sustainability perspective, understanding these mechanisms is essential for promoting inclusive, equitable, and high-quality learning environments in line with global educational goals. This study fills a gap in the literature by examining, through multivariate models, the relationship between instructor clarity and student interest as mediated by academic satisfaction and state motivation, within the framework of the Rhetorical/Relational Goals Theory in the Spanish higher education context. A quantitative, cross-sectional, ex post facto research design was employed using a survey method. A non-probabilistic convenience sampling approach was used. A total of 258 undergraduate students from the University of Extremadura enrolled in the Bachelor’s Degree in Early Childhood Education and the Bachelor’s Degree in Primary Education participated in the study. Data were analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM), including an assessment of the model’s predictive capability. The results indicated that instructor clarity was positively associated with academic satisfaction, state motivation, and student interest, with the first two variables acting as complementary mediators in these relationships. Among the predictors, state motivation emerged as the strongest determinant of student interest, whereas the direct effect of instructor clarity was comparatively weaker, highlighting the relevance of indirect pathways. The model demonstrated high predictive power and strong predictive validity with respect to student interest. Overall, the findings indicate that instructor clarity influences student interest primarily through its indirect effects on academic satisfaction and state motivation, emphasizing the importance of fostering motivational processes as key mechanisms linking teaching practices with students’ learning outcomes in higher education. Finally, it should be noted that the findings are directly aligned with Sustainable Development Goal (SDG) 4, contributing to Target 4.3 by enhancing the effectiveness and equity of teaching in higher education, as well as supporting the development of sustainable learning environments that foster long-term student engagement and academic persistence. Full article

Background: Connexins (Cx) are a family of transmembrane proteins that form gap junctions and connexin hemichannels (HCs), enabling direct intercellular communication within the nervous system. Connexin 43 (Cx43), the principal astrocytic connexin, exhibits a context-dependent dual role: under physiological conditions it maintains tissue homeostasis and metabolic support, whereas under pathological conditions excessive activation of Cx43 hemichannels promotes neuroinflammation, excitotoxicity, blood–brain barrier disruption, and secondary neural tissue damage. Other connexin isoforms also contribute to the pathogenesis of neurological and psychiatric disorders through alterations in neuronal synchronization, glial signaling, and myelin integrity. Objective: To systematize current evidence on the role of key connexin isoforms in acute nervous system injuries—including stroke, traumatic brain injury, spinal cord injury, and peripheral nerve injury—as well as chronic disorders such as neurodegenerative diseases, epilepsy, and psychiatric disorders, with particular emphasis on the functional duality of connexin channels and the therapeutic potential of their selective modulation. Methods: A systematic literature search was conducted in the PubMed, Scopus, and Web of Science databases in accordance with the PRISMA framework and the PRISMA Extension for Scoping Reviews guidelines. The review included data from experimental models, postmortem brain studies, genetic association analyses, and pharmacological intervention studies. The retrieved studies were screened, assessed for eligibility, and integrated using a qualitative narrative synthesis approach. Results: In acute neural injuries, hyperactivation of Cx43 hemichannels amplifies inflammatory signaling, edema formation, and neuronal death, whereas selective HCs inhibitors reduce lesion volume and improve functional outcomes in experimental models. Connexin 36 (Cx36) contributes to cortical spreading depolarization and seizure propagation, while Connexin 32 (Cx32) and Connexin 47 (Cx47) are critically involved in oligodendrocyte function and white-matter demyelination. In PNI, Cx43 upregulation contributes to neuropathic pain, whereas mutations in Cx32 cause hereditary demyelinating neuropathies. In neurodegenerative diseases—including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis—Cx43 hemichannel activity promotes neuroinflammation and pathological protein accumulation, while reduced Cx32/Cx47 expression disrupts metabolic support of axons. In psychiatric disorders such as major depressive disorder, bipolar disorder, and schizophrenia, decreased astrocytic connexin expression (Cx43 and Cx30) has been associated with impaired glial–neuronal communication and cognitive–emotional dysfunction. In epilepsy, increased Cx43/Cx30 expression contributes to neuronal hypersynchronization and blood–brain barrier dysfunction, whereas selective hemichannel blockade suppresses seizure activity. Conclusions: Cx—particularly Cx43—occupies a central position in the molecular mechanisms of secondary neural injury and network dysfunction. The dual functional properties of gap junctions and hemichannels determine their context-dependent effects across neurological and psychiatric diseases. Selective inhibition of pathological HCs activity shows significant neuroprotective and anticonvulsant potential and represents a promising direction for the development of targeted therapeutic strategies. Further studies are required to determine optimal therapeutic time windows, tissue-specific effects, and the long-term safety of Cx modulation. Full article

Background/Objectives: X-linked Alport syndrome (XLAS) arises from pathogenic variants in COL4A5. Truncating variants are generally classified as severe, but whether clinically meaningful heterogeneity exists within this group remains unclear. This study aimed to establish a novel Col4a5 knock-in mouse model based on a clinical variant and to determine whether truncating mutation position influences disease severity. Methods: A de novo COL4A5 frameshift variant, c.2440delG, was identified in a patient with severe early-onset XLAS. A Col4a5-G814fs knock-in mouse was generated by CRISPR/Cas9 on the C57BL/6J inbred mouse strain background and compared with the established Col4a5-G5X nonsense model using survival analysis, serial functional measurements, kidney histopathology, transmission electron microscopy, and RNA sequencing. Results: The Col4a5-G814fs knock-in mouse was successfully generated and showed loss of glomerular α5(IV) collagen chain expression. Compared with G5X mice, G814fs mice exhibited shorter survival (median 141 vs. 161.5 days, p = 0.0004), earlier onset of proteinuria, and more severe kidney functional decline. By 16 weeks, G814fs mice also showed more severe glomerular basement membrane abnormalities and more extensive glomerulosclerosis. RNA sequencing revealed a shared inflammatory gene signature in both models, together with selective upregulation of genes related to the PPAR signaling pathway and fatty acid metabolism in G814fs kidneys. Conclusions: This study reports a novel de novo COL4A5 frameshift variant and establishes the first Col4a5-G814fs knock-in mouse model. Direct comparison with the G5X model shows that distinct truncating COL4A5 mutations can be associated with substantially different disease severity, providing a useful platform for future mechanistic and therapeutic studies in XLAS. Full article

Tumor oxygenation is a key determinant of cancer biology and treatment response, correlating with angiogenesis, recurrence, and malignant progression. Hypoxia is a defining feature of glioblastoma (GBM) and adult diffuse gliomas, generating low-oxygen niches that promote invasion, stem-like states, immune suppression, and resistance to radiotherapy and temozolomide, contributing to poor outcomes. Measuring tissue partial pressure of oxygen (pO₂) and mapping its spatial heterogeneity can, therefore, inform mechanistic understanding and therapeutic development, including hypoxia-activated prodrugs, hypoxia-responsive gene therapy, and optimized radiotherapy planning. Although direct pO₂ assessment is challenging, invasive probes and multimodal imaging can characterize regional hypoxia pre-operatively, support patient stratification, monitor treatment effects, and improve outcome prediction. This review summarizes oxygen dynamics in GBM; analyzes causes of hypoxia (rapid growth outpacing supply, diffusion-limited hypoxia, and abnormal/chaotic vasculature); compares methods to quantify oxygenation from direct measurements to noninvasive imaging surrogates; and evaluates preclinical and clinical strategies that target hypoxia to enhance standard therapy, including barriers to translation. We further integrate oxygenation with cell signaling and redox biology: oxygen gradients are transduced via hypoxia-inducible factor programs and redox-sensitive pathways (NRF2/KEAP1, NOX-derived ROS, nitric oxide/S-nitrosylation, and sulfur metabolic routes), shaping mesenchymal-like transitions and cell-death programs such as ferroptosis. Framing oxygenation as both a microenvironmental and redox-signaling variable positions oxygen imaging as an entry point to biomarker-guided therapies that exploit oxidative vulnerabilities. Full article

Pinus clausa var. clausa (Chapm. ex Engelm.) Vasey ex Sarg., sand pine, is the dominant tree of biorich but ecologically compromised Southeast Florida scrub. Scrub habitats and P. clausa have dwindled due to habitat reduction and fragmentation, regional development, and fire suppression. The purpose of the present article was to seek correlates of P. clausa establishment under present unnatural development-impacted conditions using 428 field measurements at four sites to determine spatial positioning preferences relative to vegetation edges, then adding 120 measurements at a single site aimed at evaluating several potential predictors of P. clausa establishment. Potential establishment predictors were adjacency to other woody plants, depth to hard sand horizon, seed tree distance and direction, light-intensity, soil-core color, soil pH and soil surface firmness. Comparing frequency distributions of juvenile P. clausa locations with frequency distributions of random spots within the same perimeters, juvenile pines tended toward adjacency to other woody plants (chi² p < 0.0001), toward shallow hard horizons (Kolmogorov–Smirnov p = 0.0006), toward soft soil surfaces (K–S p = 0.007), and toward proximity to seed trees (K–S p = 0.004). Additionally, juvenile P. clausa were often clustered under groves of Quercus geminata Small with comparatively thin canopies. Bayesian logistic regression showed adjacency to woody plants as a strong predictor of P. clausa establishment. When alongside other plants, P. clausa establishment was mostly on the north or east side of neighboring plant edges. Overall conclusions were that juvenile Pinus clausa in SE Florida scrub fragments is sensitive to positioning relative to other woody plants, and is associated with soil surface softness, soil depth to hard horizon, and light levels, except as seedlings. Full article

To address the vibration and noise issues induced by inertial forces in marine V-type air compressors during operation, this study systematically investigates inertial force balancing and optimization. Based on dynamic analysis, analytical expressions for the first- and second-order reciprocating inertial forces and the rotating inertial force under unbalanced conditions are precisely derived. Considering the characteristics of a V-type air compressor with a V-angle of γ = 60°, the synthesis model of the first-order reciprocating inertial force is modified. The positive–negative rotating wheel system method is employed for preliminary balancing design, and the rigid–flexible coupling dynamics theory is innovatively introduced to construct a high-precision multi-body dynamics model that accounts for the flexible deformation of the crankshaft and connecting rod. Through joint simulation using ANSYS (2024R1) and Adams (2024.2), the dynamic responses of the pure rigid-body model and the rigid–flexible coupling model are compared to determine the optimal balancing configuration. The Adams/Insight module is utilized to perform multi-objective optimization of the balance iron mass. Results indicate that the rigid–flexible coupling model more accurately reflects the dynamic characteristics of the air compressor compared to the pure rigid-body model, significantly enhancing simulation accuracy. The optimized balance iron configuration effectively suppresses system vibration, with the peak X-direction bearing reaction force decreasing from 3750 N to 3610 N (a reduction of 3.7%), the vibration intensity reducing by 45.3%, and the radiated noise sound power level decreasing by 7.45%. This study provides a systematic theoretical approach and technical pathway for vibration and noise reduction, as well as for structural reliability design of marine air compressors. Full article

This paper considers the problem of controlling the motion of an autonomous underwater vehicle (AUV) following a leader in a leader–follower scheme based on visual information about the leader’s position. It is assumed that the leader is equipped with a system of light markers with known geometry, and the follower determines its relative position based on data from an onboard camera without using a hydroacoustic communication channel or direct exchange of navigation information. To synthesize the control law, a reinforcement learning method based on the Proximal Policy Optimization algorithm is used. Policy learning is performed in a simulation environment, taking into account the dynamic model of the agent in the horizontal plane and observation noise. A structure of state space, actions, and reward function is proposed, aimed at minimizing the error in relative position and orientation. Additionally, Bayesian optimization of the weight coefficients of the reward function is performed. Bayesian optimization of the reward function weights reduces the RMS tracking error from 0.24 m to 0.09 m and demonstrates that heading regulation has a significantly stronger impact on stability than position penalties. The results of modeling, testing in the Webots environment, and experiments on MiddleAUV class devices confirm the feasibility and scalability of the approach. It is shown that a single trained policy ensures stable formation maintenance when the number of follower agents and initial conditions change without additional retraining. Full article

Bloodstream infection (BSI) is a major cause of morbidity and mortality in patients with chronic kidney disease (CKD), particularly those receiving hemodialysis. Delayed identification of pathogens and their resistance profiles can lead to inappropriate therapy and adverse outcomes. This review evaluates rapid molecular diagnostic approaches for detecting pathogens and resistance markers in BSI, with emphasis on their application in CKD. These technologies provide faster microbiological information by enabling direct or accelerated detection of pathogens and selected resistance determinants. Clinical studies indicate that their use supports prompt adjustment of antimicrobial therapy, especially when combined with antimicrobial stewardship and applied after blood culture positivity. In CKD, identification of the causative organism facilitates treatment selection aligned with renal function and helps reduce unnecessary exposure to nephrotoxic agents. However, diagnostic accuracy differs among platforms, and detection of resistance genes does not consistently reflect phenotypic susceptibility. Furthermore, most evidence is derived from mixed hospital populations rather than CKD-specific cohorts. These factors require careful interpretation within the clinical context. Rapid molecular diagnostics can enhance antimicrobial decision-making in BSI, but their effectiveness depends on integration with conventional microbiology and structured care pathways. Further research in CKD populations is required to clarify their impact on clinical outcomes and to support implementation in nephrology practice. Full article

Background: Phenotype prediction for eye, hair and skin color is used in a variety of forensic applications, such as trace analysis, the identification of unknown individuals, and analysis of historical DNA traces. The aim of this study was to evaluate the predictive accuracy of the HIrisPlex-S system in a homogeneous North German population. Methods: A cohort of 155 individuals from this population was sampled, and the 41 HIrisPlex-S SNPs were genotyped using the SNaPshot workflow. In addition, the participants assessed their own eye, hair, and skin color using a standardized questionnaire. The statistical analysis included the calculation of diagnostic indicators such as sensitivity (Sens), specificity (Spec), positive and negative predictive values, and accuracy (Acc). In addition, ROC analyses were performed. Results: The results indicated that predictions of skin and hair color were less accurate, whereas eye color could be determined more reliably. Brown and blue eye colors in particular were predicted accurately (brown: Sens = 94.7%, Spec = 87.7%, Acc = 89.5%; blue: Sens = 98.5%, Spec = 57.7%, Acc = 75.7%), while intermediate eye color (Sens = 0.0%, Spec = 100.0%, Acc = 69.1%), hair color and skin color were difficult to differentiate (e.g., blond hair color: Sens = 80.8%, Spec = 56.0%, Acc = 68.2% and pale skin color: Sens = 73.8%, Spec = 44.8%, Acc = 57.2%). Conclusions: In our study, the HIrisPlex-S system primarily provided rough directional information and could distinguish between very different phenotypes but reached its limits when it comes to similar characteristics. Full article

Short-form video (SFV) platforms have become a central part of older adults’ digital lives, yet their psychological implications remain theoretically contested. Drawing on social empowerment theory, Self-Determination Theory, attachment theory, and the displacement hypothesis, this study examined whether different sources of social support—family, peer, and community—exert differential effects on life satisfaction through SFV engagement and social connectedness. Survey data were collected from 385 community-dwelling Chinese older adults (mean age = 70.6 years) and analyzed using bootstrapped serial mediation models with 5000 resamples. The results revealed clear source differentiation, as family support most strongly predicted SFV engagement and showed the largest total association with life satisfaction, consistent with a social empowerment mechanism. Community participation showed a weaker but still positive association with engagement, whereas peer support was unrelated to engagement. Across pathways, higher SFV engagement was associated with lower social connectedness, while greater social connectedness was associated with higher life satisfaction. However, none of the chained indirect effects reached significance, suggesting that social support influenced life satisfaction primarily through direct rather than serially mediated pathways. These findings demonstrate the importance of disaggregating social support by source and contribute to a more precise framework for understanding older adults’ digital well-being. Full article

Artificial intelligence (AI) is transforming logistics and supply chain management by enhancing operational efficiency, predictive analytics, and decision-making capabilities; however, the determinants of AI adoption in emerging logistics ecosystems remain insufficiently understood. This study develops and empirically examines an integrated framework combining technology-organization-environment (TOE), task-technology fit (TTF), and unified theory of acceptance and use of technology (UTAUT) to explain AI adoption in Thailand. Using survey data from 500 logistics and supply chain professionals, covariance-based structural equation modeling (SEM) was employed to validate the measurement model and test the proposed relationships. The results show that technological, organizational, and environmental factors significantly influence AI adoption at the organizational level, while task and technology characteristics enhance task-technology fit at the operational level. At the behavioral level, performance expectancy, effort expectancy, and social influence positively influence behavioral intention, which in turn drives AI adoption, with facilitating conditions also exerting a direct effect. These findings indicate that AI adoption is shaped by a cross-level mechanism involving structural conditions, operational alignment, and individual acceptance, offering theoretical and practical insights for advancing digital transformation in logistics contexts. Full article

Background and Objectives: Alloantibodies directed against human platelet antigens and human leukocyte antigens are implicated in several immune-mediated platelet disorders, including platelet transfusion refractoriness, post-transfusion purpura and fetal and neonatal alloimmune thrombocytopenia. Reliable and simultaneous detection of these antibodies is essential for accurate diagnosis and appropriate clinical management. The aim of this study was to determine the prevalence and specificity spectrum of anti-HLA and anti-HPA alloantibodies in patients with suspected immune-mediated platelet disorders using a multiplex bead-based assay, and to evaluate its diagnostic utility in a Serbian cohort. Materials and Methods: A bead-based glycoprotein-specific antibody detection assay was performed using monoclonal antibodies specific for platelet glycoproteins and HLA class I molecules, separately coupled to Luminex microbeads. Serum samples were collected from 259 patients, including 234 patients with thrombocytopenia, 11 with neonatal alloimmune thrombocytopenia, and 14 with suspected platelet transfusion refractoriness. All samples were tested using the PakLx Luminex assay, and results were interpreted with MatchIt! Antibody software. Results: Of the 259 tested samples, 72 (27.8%) were positive for HLA and/or platelet-specific antibodies. Among the positive samples, 29.2% contained HLA class I antibodies, 45.8% contained platelet-specific antibodies, and 25% showed combined HLA and platelet antibody positivity. The most frequently detected platelet-specific antibodies were directed against GPIIb/IIIa (HPA-1, -3, -4) and GPIa/IIa (HPA-5). Conclusions: This first analysis of platelet alloantibodies in a Serbian cohort demonstrates a high prevalence of antibody positivity in patients with neonatal alloimmune thrombocytopenia and platelet transfusion refractoriness, with anti-HPA-1a as the predominant specificity. The significant association between clinical presentation and antibody profile underscores the need for targeted diagnostic testing. Multiplex bead-based technology provides comprehensive alloantibody detection, facilitating optimized transfusion management in immune-mediated platelet disorders. Full article

As generative artificial intelligence (AI) becomes increasingly involved in creative processes, designers encounter a fundamental tension regarding creative control—the degree to which they dominate design direction and iterative decision-making when collaborating with AI. Existing theories offer contradictory predictions: self-determination and psychological ownership theories emphasize the benefits of control, whereas cognitive load theory highlights its cognitive costs. This tension remains empirically unresolved, particularly regarding how designer characteristics shape these competing effects. This study examines the dual-pathway mechanism linking creative control to design creativity and investigates the moderating role of design experience. A scenario-based between-subjects experiment was conducted with 226 designers and design students. Creative control exerted a positive indirect effect on design creativity through psychological ownership (effect = 0.16, 95% CI [0.09, 0.24]) and a negative indirect effect through cognitive load (effect = −0.07, 95% CI [−0.14, −0.02]), confirming the double-edged sword effect. Design experience strengthened the positive pathway while buffering the negative pathway. Creative control thus functions as a double-edged sword in designer-AI co-creation, with its net effect contingent on designer expertise. The results extend Conservation of Resources theory to human-AI collaboration contexts and inform the design of experience-adaptive AI-assisted systems. Full article

Patients undergoing hemodialysis often experience reduced quality of life, with psychological symptoms and nutritional risk representing important determinants of patient functioning. This study aimed to examine the relationships between depression, anxiety, stress, nutritional risk, mental health, and physical functioning in patients undergoing hemodialysis, with particular emphasis on the mediating role of mental health. A cross-sectional study was conducted among 199 patients receiving hemodialysis in five Croatian hospitals. Depression, anxiety, and stress were assessed using the DASS-42, quality of life using the SF-36, and nutritional risk using the NRS-2002. Associations between variables were examined using Spearman’s correlation coefficient, while structural equation modeling was used to analyze direct and indirect relationships among psychological symptoms, nutritional risk, mental health, and physical functioning. Depression and stress showed significant negative effects on mental health, while mental health showed a significant positive effect on physical functioning. Nutritional risk had a significant direct negative effect on physical functioning. Mental health significantly mediated the relationship between depression and stress and physical functioning. These findings indicate that psychological symptoms and nutritional risk are important determinants of functioning and quality of life in hemodialysis patients and support the need for an integrated care approach that includes regular psychological and nutritional screening. Full article