Search Results (20,723)

Background/Objectives: This study proposes a comprehensive classification framework for the automatic detection of Alzheimer’s disease using handwriting data. An enriched feature space is constructed by combining 18 baseline features extracted from raw handwriting signals with 30 additional features derived from established handwriting analysis studies, resulting in a total of 48 features. To enhance clinical practicality, a task reduction analysis is conducted by comparing the full dataset containing 25 handwriting tasks with a reduced dataset comprising 14 selected tasks. Methods: The proposed framework employs a two-stage evaluation strategy involving four feature selection methods (Random Forest Feature Importance, Extreme Gradient Boosting Feature Importance, L1 Regularization and Recursive Feature Elimination), three normalization techniques (Unnormalized, Min–Max and Z-Score), and five baseline machine learning classifiers (Random Forest, Logistic Regression, Multilayer Perceptron, XGBoost and Support Vector Machines). In the second stage, a dynamic ensemble learning strategy is introduced, where the most effective classifiers are adaptively selected for each cross-validation fold and integrated using soft and hard voting schemes. Results: The experimental results demonstrate that reducing the number of tasks leads to an improvement in average classification accuracy from 79.47% to 81.03%, while simultaneously decreasing training time and memory consumption by approximately 40% and 35%, respectively. The highest classification performance, achieving an accuracy of 94.20%, is obtained using the Hard Ensemble combined with L1-based feature selection. Conclusions: These findings highlight that the joint use of enriched feature representations, task reduction, and dynamic ensemble learning provides an effective and computationally efficient solution for handwriting-based Alzheimer’s disease detection. Full article

Background: The Index of Cardiac Electrophysiological Balance (ICEB) has emerged as a electrocardiographic marker reflecting the equilibrium between ventricular depolarization and repolarization. Although obesity is known to alter cardiac electrophysiology, the combined influence of body mass index (BMI) and objective nutritional status on ICEB and its heart rate-corrected form (ICEBc) remains insufficiently defined. This study aimed to investigate the associations between BMI categories, nutritional status, and cardiac electrophysiological balance. Methods: This cross-sectional study included 591 adult patients classified as normal-weight, overweight, or obese according to BMI. Electrophysiological assessment of ICEB (QT/QRS) and ICEBc (QTc/QRS) values was calculated from standard 12-lead electrocardiogram recordings. Participants’ nutritional status was analyzed using validated clinical indices such as the Prognostic Nutritional Index (PNI), Controlling Nutritional Status (CONUT), Geriatric Nutritional Risk Index (GNRI) and Hemoglobin–Albumin–Lymphocyte–Platelet (HALP) score. Results: According to the results, both ICEB and ICEBc showed significant differences among BMI categories (p < 0.001). ICEB/ICEBc exhibited a non-linear distribution. The ICEB/ICEBc values were found to be minimum in the normal weight group at 4.22 ± 0.54/4.87 ± 0.66 and maximum in the obese group at 4.27 ± 0.51/4.99 ± 0.59. The ICEB/ICEBc value closest to the optimal physiological limits was found in the overweight group at 4.04 ± 0.53/4.59 ± 0.58. Higher ICEBc quartiles were accompanied by increased GNRI (120.9 ± 13.7, 129 ± 15.1, 130.5 ± 16.3, 131.8 ± 17.6, p < 0.001)and decreased HALP scores (59.7 ± 24.4, 56.1 ± 25.3, 55.2 ± 25.9, 51.1 ± 19.4, p: 0.025). Conclusion: The association between BMI and cardiac electrophysiological balance is non-linear and appears to be modulated by nutritional and inflammatory status. ICEBc may represent a more sensitive marker than ICEB for detecting subtle electrophysiological alterations related to obesity. Full article

Neural field dynamics in the cerebral cortex exhibit complex spatiotemporal patterns inadequately captured by classical integer-order diffusion models that assume exponentially decaying spatial interactions. This study establishes a stochastic fractional FitzHugh–Nagumo framework incorporating power-law spatial correlations through fractional Laplacian operators, providing explicit parameterization of non-local cortical connectivity characteristics. The inverse problem of estimating fractional orders and model parameters from electroencephalographic data is addressed through multi-objective optimization with rigorous train–test validation. Systematic sensitivity analysis across the parameter space $({\alpha }_u,{\alpha }_v)\in [1.0,2.0]\times [1.0,2.0]$ identifies optimal subdiffusive characteristics at ${\alpha }_u={\alpha }_v=1.5$, corresponding to power-law spatial kernels $C\left(x\right)\sim {\left|x\right|}^{-1.5}$ consistent with anatomical connectivity measurements. The optimized model achieves out-of-sample performance $R^2=0.973$ on held-out test data, approaching the measurement noise ceiling. While classical FitzHugh–Nagumo models achieve comparable test accuracy, the fractional framework provides enhanced interpretability through explicit spatial interaction parameterization. The fractional orders serve as quantitative biomarkers of cortical network organization, enabling data-driven characterization across brain states and neurological conditions. The methodology establishes computational foundations for clinical applications in epilepsy monitoring, neurodegenerative disease detection, and brain–computer interfaces. Full article

This study investigates the impact of the Slow Food movement on sustainability and local gastronomy in Northern Cyprus. After reviewing key concepts such as sustainable gastronomy, local food heritage and regional practices, the research focuses on the five Cittaslow regions of Northern Cyprus and the development of Slow Food activities since 2013. Using a qualitative design with purposive sampling, semi-structured interviews were conducted with twelve participants, including local producers, chefs and regional administrators. The study identifies the challenges faced by local businesses, the role of Slow Food in promoting sustainable practices and the ways regional actors contribute to cultural and environmental preservation. Findings highlight both progress and gaps, offering practical recommendations and outlining areas for future research. As one of the few studies examining Slow Food in Northern Cyprus, the research provides valuable insights and contributes significantly to the existing literature. Full article

As societies confront accelerating sustainability challenges, understanding the individual-level orientations that support collective action has become increasingly important. This study examines the association between educational attainment and three theoretically distinct sustainability-relevant value orientations using cross-national survey data. Drawing on the World Values Survey Wave 7, we analyze responses from 65,608 individuals across 65 countries using weighted least squares regression with country fixed effects to investigate how education relates to norm orientation, future orientation, and inclusion. The analysis reveals substantial variation in the strength of these associations across value dimensions. Education demonstrates a particularly strong relationship with future orientation, yielding a standardized effect size of 0.497, while showing considerably weaker associations with inclusion and norm orientation. Moderation analyses uncover important demographic contingencies, indicating that education gradients for norm orientation and inclusion weaken significantly with age, whereas the education-future orientation relationship remains stable across age groups. A modest gender difference emerges for future orientation, with slightly attenuated education effects among women. These findings suggest that education contributes to sustainability-relevant values primarily through cognitive pathways that enhance temporal perspective rather than through socialization into normative compliance or expansion of social tolerance. The results carry implications for education policy design and sustainable development initiatives. Full article

Background: Fractal dimension (FD) analysis has been widely applied to medical and dental images to quantify trabecular bone complexity. Panoramic radiographs are routinely used in dental practice; however, the capability of two-dimensional panoramic imaging combined with FD analysis to detect subtle mandibular trabecular alterations associated with systemic diseases such as type 2 diabetes mellitus (T2DM) remains uncertain. Methodology: This retrospective cross-sectional study included 106 individuals, comprising 53 patients diagnosed with T2DM and 53 non-diabetic controls. Fractal dimension values were calculated using a standardized box-counting algorithm from four anatomically defined mandibular regions of interest (anterior, premolar, molar, and condylar) on panoramic radiographs. Intergroup comparisons of FD values were performed to evaluate the sensitivity of panoramic radiograph-based FD analysis in detecting diabetes-related trabecular differences. Results: No statistically significant differences in fractal dimension values were observed between the T2DM and control groups across all evaluated mandibular regions (p > 0.05). These findings highlight methodological limitations related to image dimensionality, projection geometry, and regional trabecular heterogeneity. Conclusions: Fractal analysis remains a valuable quantitative tool; however, its application to panoramic radiographs should be interpreted cautiously when used to assess systemic bone alterations. Full article

Background: Autologous arteriovenous fistulas (AVFs) are the preferred vascular access modality for hemodialysis due to superior durability and lower infection rates. However, long-term secondary functional patency remains a critical determinant of dialysis success and patient survival. Although sex-related differences in vascular access outcomes have been reported, their impact on long-term secondary patency remains insufficiently clarified. Objective: The primary objective of this study was to evaluate long-term gender differences in the secondary functional patency of AVFs and to determine clinical, anatomical, and procedural factors contributing to these disparities. Methods: A retrospective cohort study including 968 ESRD patients undergoing AVF creation between 2012 and 2024 was conducted. Secondary patency was analyzed using Kaplan–Meier survival curves. Multivariate logistic regression identified independent predictors. The overall primary functional patency rates were 78.9% at 1 year, 71.2% at 3 years, and 62.7% at 5 years. When stratified by gender, male patients demonstrated primary patency rates of 80.3% at 1 year, 72.8% at 3 years, and 64.5% at 5 years, whereas female patients showed slightly lower rates of 77.3% at 1 year, 69.4% at 3 years, and 60.6% at 5 years. Conclusions: Female gender, particularly in the postmenopausal period, is an independent determinant of reduced long-term secondary AVF patency. Early identification of high-risk patients and structured risk factor optimization are essential to improve vascular access durability. Full article

Background: Obstructive sleep apnea (OSA) syndrome is a common sleep-related breathing disorder characterized by recurrent upper airway collapse during sleep and is closely associated with metabolic dysregulation, including insulin resistance, adipose tissue dysfunction, and impaired lipid metabolism. Perilipin-2 (PLIN-2), a lipid droplet-associated protein involved in triglyceride storage and regulation of lipolysis, may reflect alterations in lipid homeostasis associated with OSA. Objective: This study aimed to evaluate the association between serum PLIN-2 levels and OSA and to assess the relationship between PLIN-2 concentrations and disease severity. Methods: A total of 231 participants were included in this study, comprising 70 healthy controls and 161 patients with OSA. Patients were classified according to apnea–hypopnea index (AHI) as having mild (n = 60), moderate (n = 52), or severe OSA (n = 49). All participants underwent overnight polysomnography (PSG). Results: Serum PLIN-2 levels were significantly higher in patients with OSA and increased progressively with disease severity. PLIN-2 levels were positively correlated with polysomnographic indices of OSA severity, including AHI and oxygen desaturation index. ROC analysis demonstrated good discriminative performance of PLIN-2 for OSA presence and for distinguishing mild from severe OSA. Conclusions: This study is the first to demonstrate an association between serum PLIN-2 levels and OSA. Our findings suggest that PLIN-2 may serve as a novel biomarker reflecting metabolic and lipid-related disturbances in OSA and may provide new insights into the pathophysiological link between intermittent hypoxia and altered lipid metabolism. Full article

Powder-bed arc additive manufacturing (PBAAM) may reduce the cost of powder-bed metal additive manufacturing and enable thicker layers than laser powder bed fusion (LPBF), but melt-track stability limits are not well established. Here, 316L stainless steel powder (15–53 µm) was melted by a TIG-based arc in a custom powder-bed system while varying current, travel speed, layer thickness and hatch distance. Single tracks on an inclined bed (≈0–0.4 mm thickness) were used to identify continuity loss and melt-pool width, quantified from top-view images via width profiles, a gap-based continuity metric and the coefficient of variation. Parallel-track tests at 0.15, 0.20 and 0.25 mm layer thickness with hatch distances set to 25%, 50% and 75% of the measured melt-pool width assessed inter-track bonding and lack of fusion, and selected parameters were validated in five-layer builds. Higher current with low-to-moderate travel speeds produced wider, more stable melt pools on the inclined bed. Hatch ratios of 25–50% were the most effective for sustaining fusion in single layers and multi-layer builds, whereas 75% promoted unbonded regions and narrow-track morphologies. Overall, PBAAM can process substantially thicker layers with relatively simple equipment, but requires a narrow, carefully tuned window to balance continuity, fusion and heat accumulation. Full article

We introduce a new class of fractional remainder operators, denoted by $R_{\alpha ,n}^{\xi +}$ and $R_{\alpha ,n}^{\eta -}$, which generalize and unify various classical integral identities. Using these operators, we formulate refined Hermite–Hadamard and trapezoidal inequalities for differentiable functions. The novelty of our approach lies in its symmetric kernel structure, which facilitates tighter error bounds. Numerical examples are given, including applications to non-differentiable convex functions, to demonstrate the applicability and limitations of the derived results. Full article

Rising microbial resistance to synthetic disinfectants has intensified the search for chemically synthesized natural alternatives, such as ginger-derived bioactive compounds. Several bioactive compounds, including Zingerone, Gingerols, and Shogaols, have been shown to possess antimicrobial activities. However, the antimicrobial efficacy of these compounds as disinfectants at varying temperatures and contact times is poorly understood. Therefore, understanding the temperature- and time-dependent effects of contact is crucial for optimizing the potential application of these compounds in various antimicrobial strategies. In this study, the antimicrobial activities of three chemicals, 10% [6]-Gingerol, Zingerone, and Shogaols, were evaluated against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. Furthermore, the variations in temperatures (5 °C, 25 °C, and 37 °C) and contact time (1, 5, and 60 min) were assessed based on CFU counts, log₁₀ reductions, percent kill, and decimal reduction time. The findings of this study indicated that 10% Zingerone completely inactivated all tested organisms in 60 min at all temperatures. Although 10% [6]-Gingerol and Shogaol exhibited temperature- and time-dependent effects, they failed to completely inactivate the bacteria and fungi after 60 min. Furthermore, both temperature and contact time were shown to influence the efficacy of the tested disinfectants, providing a significant time- and temperature-dependent reduction in viable cells across all tested organisms. Full article

Background and Objectives: Hypocalcemia due to hypoparathyroidism (HypoPTH) is the most common complication following thyroid surgery, typically resulting from iatrogenic removal, tissue damage, or compromised vascularization of the parathyroid glands. Patients with persistent HypoPTH are at risk for long-term complications such as osteoporosis, cardiac dysfunction, and renal impairment. Lifelong regulation of calcium levels is therefore essential to prevent morbidity and mortality associated with these complications. In this study, we aimed to evaluate the functional engraftment efficacy of 3D bioprinted human parathyroid tissue constructs in a xenograft model in vivo. Materials and Methods: Primary cells obtained from freshly excised human parathyroid tissue specimens were isolated and 3D bioprinted using alginate-based bioink. The bioprinted tissue constructs were implanted into CD1 athymic mice. Histopathological evaluation of the grafted constructs was performed at different time points. In addition, surface calcium-sensing receptor (CaSR) expression was assessed by immunofluorescence as an indicator of functional parathyroid tissue engraftment. Results: The presence of CaSR on parathyroid cells within the 3D-printed scaffolds confirmed the persistence of functional parathyroid cells following implantation. In tissue samples obtained during the first, second, and third weeks after implantation, CaSR positivity was consistently observed in the parathyroid cells. However, at the three-month follow-up, the pores within the scaffolds were found to be filled with calcified material and replaced by fibrotic tissue. At this stage, the absence of parathyroid hormone (PTH) expression indicated a loss of functional activity in the grafted biomaterial. Conclusions: Human primary parathyroid cells were successfully isolated, and a functional, hormone-active parathyroid tissue substitute was developed ex vivo using 3D-bioprinted hydrogel scaffolds combined with autologous cells. Although short-term functional engraftment was achieved, long-term graft viability and hormonal activity were limited due to scaffold degradation and fibrosis. These findings indicate the necessity for further improvement in scaffold biocompatibility to enhance the therapeutic potential of 3D-bioprinted parathyroid tissue constructs for in vivo applications. Full article

Objective: This study aimed to investigate erythrocyte morphological alterations in hematological malignancies, with particular emphasis on structural differences among leukemia subtypes and anemia. Materials and Methods: Peripheral blood samples were obtained from 60 patients, including individuals with anemia (n = 10), acute lymphoblastic leukemia (ALL, n = 15), acute myeloid leukemia (AML, n = 15), chronic lymphocytic leukemia (CLL, n = 15), and chronic myeloid leukemia (CML, n = 5), as well as 10 healthy controls. Erythrocyte morphology was evaluated using light microscopy and scanning electron microscopy. Morphological abnormalities, including loss of biconcavity, poikilocytosis, echinocyte transformation, burr cells, and stomatocytes, were assessed in accordance with International Council for Standardization in Haematology (ICSH)-based morphological definitions. Results: Distinct erythrocyte morphological alterations were observed across disease groups. AML cases demonstrated pronounced central depression-like or perforation-like structures and hypochromasia. Lymphoid malignancies, particularly ALL and CLL, exhibited increased echinocyte formation, whereas chronic leukemias showed a higher prevalence of stomatocytes and cup-shaped cells. Quantitative scoring indicated that loss of biconcavity was most prominent in anemia, followed by AML, CML, ALL, and CLL. Poikilocytosis was most frequent in anemia, followed by ALL, CLL, AML, and CML. Conclusions: The findings indicate that erythrocyte shape alterations are more heterogeneous and prominent in lymphoid leukemias, whereas myeloid leukemias exhibit distinct ultrastructural membrane abnormalities. Although studies focusing on erythrocyte morphology in leukemia remain limited, the present results provide a foundational morphological reference dataset that may support the development and validation of artificial intelligence-based diagnostic approaches. Further studies involving larger cohorts and expanded imaging analyses are warranted to improve diagnostic accuracy and translational applicability. Full article

Background: Male infertility remains a significant clinical challenge. The KISS1R-CATSPER3 signaling axis and acrosomal integrity are vital for fertilization, yet their regional expression patterns in subfertile men are not fully characterized. Objectives: This study investigated regional expression patterns of KISS1R and CATSPER3 and evaluated acrosomal integrity in oligozoospermic and normozoospermic individuals, accounting for demographic confounders. Methods: A total of 52 participants were selected from 568 candidates and divided into normozoospermic (n = 26) and oligozoospermic (n = 26) groups. Analysis included qPCR and immunofluorescence for KISS1R and CATSPER3. Regional expression was independently scored by blinded researchers. Statistical models were adjusted for age and body mass index (BMI). Results: Acrosomal integrity was significantly lower in the oligozoospermic group (p < 0.001). After adjusting for age and BMI, overall protein expression of CATSPER3 and KISS1R remained significantly lower in oligozoospermic men (p < 0.05). Regional analysis showed that CATSPER3 head staining differences disappeared after adjustment, whereas lower tail expression persisted. Higher KISS1R head expression in oligozoospermic men remained significant. qPCR showed no differences in KISS1R or CATSPER3 mRNA levels (p > 0.05), indicating post-translational regulation. Conclusions: KISS1R-CATSPER3 axis downregulation is a hallmark of oligozoospermia that persists independently of age and BMI. Regional protein instability, despite stable mRNA levels, suggests that post-translational regulation is critical for fertility. These markers may serve as potential diagnostic or therapeutic indicators for male infertility. Full article

Background: SARS-CoV-2 infection during pregnancy has been associated with systemic inflammatory responses and placental pathology; however, the molecular mechanisms underlying placental involvement remain incompletely understood. The endocannabinoid system plays a critical role in placental development, immune regulation, and vascular homeostasis. Materials and Methods: Placental tissues were obtained from 20 healthy pregnant women and 20 women with confirmed SARS-CoV-2 infection who had recovered by the time of delivery. Demographic and laboratory parameters were recorded. Histopathological evaluation was performed using hematoxylin and eosin staining. Immunohistochemical analysis of cannabinoid receptor 1 (CNR1) and cannabinoid receptor 2 (CNR2) expression was conducted, supported by quantitative digital image analysis using QuPath. Network-based protein–protein interaction and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to explore potential molecular mechanisms. Results: COVID-19-positive placentas exhibited prominent histopathological alterations, including increased fibrinoid deposition, syncytial knot formation, vascular congestion, and intervillous inflammatory cell infiltration. Systemic inflammatory and coagulation markers, particularly neutrophil percentage, C-reactive protein, D-dimer, and fibrinogen levels, were significantly elevated in the COVID-19 group. CNR1 and CNR2 expressions were markedly increased across multiple placental compartments, including decidual cells, trophoblastic layers, syncytial knots, and Hofbauer cells. Quantitative digital analysis confirmed significant upregulation of both receptors. Bioinformatic analysis revealed enrichment of endocannabinoid signaling, cAMP-related pathways, and inflammatory mediator regulation of TRP channels. Conclusions: The findings indicate that SARS-CoV-2 infection is associated with coordinated inflammatory, structural, and molecular alterations in the placenta. Upregulation of CB1 and CB2 suggests an active involvement of the endocannabinoid system in placental immune and vascular responses to COVID-19, highlighting its potential relevance for understanding placental pathology associated with maternal viral infections Full article