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Association of metabolic dysfunction-associated steatotic liver disease with extrahepatic cancers and sarcopenia
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Diagnostic accuracy of artificial intelligence models in childhood exanthematous diseases: a comparative analysis against clinical diagnosis
No full textPurpose: Differentiating among exanthematous diseases is frequently challenging due to their overlapping symptomatology. We, therefore, aimed to evaluate the diagnostic accuracy of a consultant physician, a resident physician, and various AI models (ChatGPT-5, Gemini, Copilot) in this context. Methods: We prospectively enrolled 291 patients treated for exanthematous diseases at our clinic between January 2024 and July 2025. The AI models were first tasked with making a diagnosis based solely on cutaneous images and subsequently with both images and accompanying clinical findings. The diagnoses rendered by the consultant, the resident, and the AI models were then compared against the definitive diagnosis. Results: When benchmarked against the definitive diagnosis, the consultant achieved the highest diagnostic accuracy (96.6%), followed by ChatGPT (with clinical data, 86.9%), Copilot (with clinical data, 81.4%), Gemini (with clinical data, 78.7%), and the resident physician (72.5%). In contrast, models without clinical data performed poorly, with the lowest accuracy recorded at 30.6% by Copilot. In ROC analysis against the consultant, the resident (AUC:.875) and AI models with clinical data—ChatGPT (AUC:.898), Gemini (AUC:.856), and Copilot (AUC:.818)—all demonstrated good diagnostic power (p <.001). The ChatGPT model without clinical data showed moderate diagnostic power, whereas the Copilot and Gemini models without data were not statistically significant. Performance metrics (sensitivity, specificity) were: ChatGPT (with data) (89.7%, 90.0%); Copilot (with data) (83.6%, 80.0%); Gemini (with data) (81.1%, 90.0%); the resident (75.1%, 100.0%); ChatGPT (no data) (51.6%, 90.0%); Gemini (no data) (33.5%, 100.0%); and Copilot (no data) (31.7%, 100.0%). The consultant's diagnostic performance was significantly superior to all other interpreters and models (p <.001 for all comparisons). Conclusion: This study establishes the diagnostic utility of AI models in pediatric exanthematous diseases, with ChatGPT-5 demonstrating the greatest accuracy when augmented with clinical data. The findings position these models as powerful assistive tools for clinicians but affirm that they do not yet supplant the indispensable expertise of a consultant physician, who remains the gold standard for diagnosis. (Table presented.
Introduction to Data Mining
No full textData Mining Dersi 1. Hafta Ders Notu Konusu : Introduction to Data Minin
Barriers and drivers for penetrating the global maritime labour market: Empirical evidence from merchant seafarers
No full textThe maritime transport sector is characterised by unique dynamics, including the ease of crew exchange and the increased use of standardised languages by seafarers. These factors have led to greater multinationalism among ship crews, which presents several managerial, cultural and operational challenges. This study examines the factors, drivers and barriers affecting the integration of professional seafarers into the global maritime labour market under multinational working conditions. The study introduces a ‘harmony’ variable, derived from six attitudinal items, as a proxy for seafarers' adaptability to multinational crew environments. A mixed-method design was employed, integrating quantitative analyses with qualitative insights to provide a comprehensive understanding of multinational working. A hierarchical cluster analysis was conducted to classify the respondents according to their harmony values. The classification of seafarers according to harmony scores was followed by the analysis of quantitative data from 322 respondents and qualitative data from 125 respondents, respectively. The findings indicate that there were no significant differences in the duration of multi-national working for seafarers at varying levels of harmony. Moreover, an analysis of the factors that contribute to the duration of multinational work revealed that marital status, competence, and raising with maritime culture were significant predictors. In the context of multinational working, it has been observed that seafarers tend to express concerns regarding their English language proficiency, professionalism, and cultural properties. However, the participants identified several challenges that lie beyond the capabilities of seafarers, including the need for government support, global marketing, and accreditation. These findings underscore the need for policy interventions in maritime education and international cooperation to prepare seafarers for multicultural working environments. Therefore, policymakers should undergo critical reorganizations in maritime education and training to integrate their mariners with the global labour market
Fibrosis-4 score and postoperative outcomes in metabolic dysfunction-associated steatotic liver disease
No full textBackground/Aims: The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) is increasing globally. The Fibrosis-4 (FIB-4) score is a noninvasive biomarker used for assessing potential advanced fibrosis. The study aimed to evaluate the role of the FIB-4 score in predicting postoperative complications and mortality in patients undergoing surgery. Materials and Methods: This multicenter retrospective study included 11 072 patients who underwent surgery under general anesthesia. Demographic and clinical data-including age, gender, comorbidities, FIB-4 scores, American Society of Anesthesiologists classification, postoperative complications, and mortality-were analyzed. Results: A total of 1667 MASLD patients were included. Patients were classified based on FIB-4 scores: 70% (n = 1167) had FIB-4 = 2.67. Due to the limited number of patients with possible advanced fibrosis (FIB-4 >= 2.67), propensity score (PS) matching was performed. After PS matching, patients with a high FIB-4 score exhibited a significantly higher rate of postoperative complications (P < .001), and 12-month mortality was elevated (11%), although the difference was not statistically significant (P = .481). Conclusion: A high FIB-4 score may serve as a predictive marker for postoperative complications in patients with MASLD undergoing surgery
Alterations in the lipid profile in acne vulgaris patients: A meta-analysis
No full textObjective Previous studies have reported inconsistent findings regarding alterations in lipid profiles among patients with acne vulgaris (acne). This meta-analysis aimed to resolve these inconsistencies.Methods A systematic search was conducted in Web of Science, Scopus, and PubMed. Lipid profile levels were compared between patients with acne and healthy controls. Mean values and standard deviations for total cholesterol, triglycerides, low-density lipoprotein, and high-density lipoprotein were used to calculate standardized mean differences with 95% confidence intervals.Results A total of 916 articles were initially identified, of which 38 studies comprising 2485 patients met the eligibility criteria. The pooled analysis demonstrated that patients with acne had significantly higher levels of total cholesterol (pooled standardized mean difference = 0.92, 95% confidence interval: 0.55-1.28), triglycerides (pooled standardized mean difference = 0.82, 95% confidence interval: 0.51-1.14), and low-density lipoprotein (pooled standardized mean difference = 1.52, 95% confidence interval: 1.11-1.92) as well as significantly lower high-density lipoprotein levels (pooled standardized mean difference = -0.45, 95% confidence interval: -0.69 to -0.21). Subgroup and meta-regression analyses were performed to identify the sources of significant heterogeneity. Subgroup analyses further revealed significant alterations in lipid profiles among female patients and in studies conducted in Egypt and Saudi Arabia.Conclusion Alterations in lipid profiles were observed in patients with acne
Comparative performance and economic analysis for different clean energy and hydrogen production systems: A case study for Türkiye
No full textThis study introduces a novel, data-driven assessment of an integrated solar-wind hybrid system for green hydrogen and electricity generation in Türkiye. In contrast to most modelling-based research, the analysis employs high-resolution real field data comprising 6958 measurements to capture annual variability and system dynamics under three operational modes: Scenario S-1 (hydrogen-only production via electrolysis), Scenario S-2 (simultaneous hydrogen and electricity generation), and Scenario S-3 (electricity-only production). The findings demonstrate that hydrogen production ranged between 125 kg (May) and 300 kg (July), whilst overall system efficiency varied from 24 % to 80 %, peaking in S-3 due to lower conversion losses. Hydrogen production costs were calculated between 2.40 and 2.95 /kWh. Among all configurations, the hybrid mode (S-2) achieved the most balanced performance, combining steady power output, high resource utilisation, and cost efficiency. Beyond its technical outcomes, this study provides the first multi-scenario, field-validated comparative analysis for Türkiye, incorporating thermodynamic and economic perspectives. By highlighting seasonal fluctuations, grid independence, and the benefits of energy security, the results provide an innovative framework for designing resilient hybrid renewable-hydrogen systems. Overall, the work establishes a scientific foundation to guide national energy strategies, investment decisions, and low-carbon policy development
Spatial and temporal distribution of the egg and larval stages of the european anchovy, engraulis encrasicolus (linnaeus, 1758) in relation to environmental conditions in the South-Eastern Black Sea
No full textStock assessments are one of the most important stages of fisheries. The study focused on whether this region was a spawning area for anchovy stocks by investigating the abundance of anchovy eggs and larvae in the Southeastern Black Sea. During the 6-month vertical sampling process, a total of 2406 anchovy eggs, including 957 live eggs and 1449 dead eggs while a total of 502 anchovy larvae were also sampled during this process. In the study area, the mean densities were 237.38±141.67 eggs/m² and 49.20±28.97 larvae/m². No anchovy eggs or larvae were encountered during the first ichthyoplankton survey in May. During the sampling period, the most productive month in terms of eggs and larvae was determined as August (591.8±587.99 eggs/m2; 147.5±132.74 larvae/m2), and the highest sea water values were measured for surface water temperature (25.47°C), chlorophyll-a (2.02 µg/L), salinity (18.53‰) and dissolved oxygen (7.94 mg/L). Considering the results obtained, it was concluded that the Southeastern Black Sea is an important breeding ground for anchovy and that the abundance of eggs and larvae increased with rising temperature and nutrient levels
Sustainable modification of bitumen using waste toner and lignin
No full textIntegrating waste materials into road infrastructure is essential for environmental sustainability and resource efficiency. This study addresses the modification of short-term-aged 50/70-penetration-grade bitumen using two sustainable additives: waste toner powder and lignin. Waste toner was added at weight percentages of 4%, 8%, 12%, and 16%, while lignin was added at 15% and 20%. Since these modifiers have individual uses, this study examines how they may strengthen the oxidized binder. It focuses on extending the lifespan of the mixture by combining industrial and bio-based polymers. The main aim was to delineate the impact of these modifiers on the physical consistency, low-temperature flexibility, and microstructural morphology of the binder. The results show that both modifiers increase binder stiffness by reducing penetration at all modification rates. The resins in the waste toner enhance the polymer matrix, and the lignin’s aromatic structure increases the elastic components, improving high-temperature stability. However, ductility tests showed a reduction in elongation capability, suggesting a brittle state at lower temperatures. Also, waste toner additive is identified as the ideal modifier for high-temperature applications. SEM analysis illuminated the mechanisms underlying these performance modifications. Both additives had homogeneous distribution and good bitumen matrix interfacial bonding at lower concentrations
Nonlinear receding contact mechanics of functionally graded layers for aerospace structures: a symmetry-based analytical and FEM study
No full textFunctionally graded materials (FGMs) are widely applied in spacecraft structural design, thermal protection systems, and planetary landing mechanisms, benefiting from their ability to resist large thermal, pressure, and force gradients. To assess structural response behaviors for lander missions, docking maneuvers, and force transfer in layered aerospace structures, analyzing the contacts subjected to heavily stressed areas becomes very important. This article investigates the receding contact between a functionally graded top layer and a uniform substrate lying on a Winkler elastic foundation using the elasticity theory. An analytical approach has been validated using a finite element method (FEM) implemented in ANSYS. Comparison between the analytical solution and the FEM solution has been conducted for different stamp radii, elastic foundation stiffnesses, and ratios of shearing modulus for various realistic materials in the aerospace field. The data indicate very good convergence between the two solutions for both the length of contacts and the normal stress distribution, where differences are always below 3%. An increase in stamp radius leads to an extension of the contacts as well as a reduction in normal stresses and elevated stiffness and shearing modulus ratio contribute to smaller contacts and higher stresses. The validated methodological approach offers a realistic means for predicting force transfer mechanisms in spacecraft landing pads, multi-layer insulation panels, adaptive space structures, and functionally graded parts subjected to localized loads. This work offers predictive capabilities for space material interface design and optimization for harsh mechanical environments