Search Results (2,449)

Background and Objectives: Positron emission tomography with 18F-FDG (PET-CT) provides a quantitative measure of tumor metabolic activity through the maximum standardized uptake value (SUVmax) of lung tumors—a measure of metabolic activity that may have prognostic value in non-small cell lung cancer (NSCLC). This study evaluated whether preoperative tumor SUVmax predicts outcomes in resected NSCLC. Materials and Methods: This single-center retrospective study included 209 consecutive patients with resected NSCLC who had preoperative FDG PET-CT. SUVmax of the primary tumor was recorded, and patients were stratified into low- and high-SUVmax groups to evaluate survival outcomes. Results: Median age was 62 years and 77% were male. Histologic subtypes were adenocarcinoma (44%), squamous carcinoma (43%), and others (13%), with stage I–III distribution of 39.7%, 33.5%, and 26.8%, respectively. SUVmax demonstrated moderate discrimination for mortality (AUC = 0.652), with an optimal cutoff of 11.14. Patients with SUVmax ≥ 11.14 had significantly worse OS and DFS. However, on multivariate analysis, SUVmax was not an independent predictor of outcomes, while extracapsular invasion (OS) and adjuvant chemotherapy (DFS) remained significant. Conclusions: In this cohort of resected NSCLC, high preoperative SUVmax (≥11.14) was associated with more advanced tumor stage and worse OS/DFS but was not an independent prognostic factor after accounting for other variables. Tumor invasiveness and use of adjuvant therapy were stronger outcome predictors. Preoperative SUVmax may help identify high-risk patients when considered alongside established clinicopathologic factors. Full article

Background: Parabens are frequently utilized as preservatives in processed foods; nevertheless, the primary dietary factors contributing to exposure in northern Thailand remain undetermined. Methods: A cross-sectional study was conducted among 130 adults in Northern Thailand. Dietary intake was assessed using self-reported food consumption data combined with previously measured paraben concentrations. Due to the skewed distribution of intake, participants were classified into lower and higher exposure groups. LASSO regression was applied for variable selection, followed by multivariable logistic regression to identify dietary predictors of exposure. Results: Several processed food items were significantly associated with higher paraben exposure, including soft drinks, potato chips, and canned fish. No demographic factors were significantly associated with exposure. The final model demonstrated good explanatory power and classification performance. Conclusions: These findings suggest that routine consumption of certain processed foods and beverages may play a larger role in exposure than individual characteristics, and they highlight practical targets, particularly soft drinks, potato chips, and canned fish, for community-based health-promotion strategies aimed at reducing unnecessary preservative intake. Full article

Tropical estuaries are highly productive yet increasingly threatened by natural and anthropogenic pressures, necessitating robust ecological assessments for sustainable management. This study assesses the spatio-seasonal distribution of macrobenthic assemblages and evaluates the ecological health of the Sangu River estuary based on their bioindicator potential. Sediment samples for macrobenthos analysis were collected during three seasons (pre-monsoon, monsoon, and post-monsoon) from nine stations across three estuarine zones influenced by sedimentation, aquaculture, and terrestrial runoff. We employed microbenthic diversity indices, multivariate analyses, the AZTI’s Marine Biotic Index (AMBI), and multivariate-AMBI (M-AMBI) to evaluate the ecological health status of the study area. Our study recorded 13 taxa, dominated by Nereididae (40.90%), Mysidae (14.29%), and Capitellidae (10.20%). Macrobenthos diversity (Shannon diversity) ranged from 0.80 to 1.22, and abundance showed negative correlations with salinity (r = −0.29) and silt (r = −0.22), and a positive correlation with dissolved oxygen (r = 0.29). Analysis of Similarities (ANOSIM) indicated that seasonal variation was the primary driver of community structure (p < 0.001). AMBI classified most stations as having good to moderate ecological status, while M-AMBI indicated moderate disturbance across seasons, with elevated proportions of opportunistic taxa (EG V: 14.4–32%) reflecting persistent anthropogenic stress. This study provides the first empirical ecological baseline for the Sangu River estuary and highlights the applicability of family-level AMBI assessments in data-limited tropical estuarine systems. Full article

This paper investigates the fractional calculus of distributions supported on ${\mathbb{R}}^{+}$ in the sense of L. Schwartz, based on distributional convolutions. We further study a generalized Bagley–Torvik equation involving an arbitrary number of fractional derivative terms with orders in the interval $(0,2)$. The existence and uniqueness of solutions for its nonlinear form are established in a space of continuous functions by applying Banach’s contraction principle, the Leray–Schauder fixed-point theorem, inverse operators, and the multivariate Mittag–Leffler function. Finally, several examples are presented, in which the values of multivariate Mittag–Leffler functions are computed to illustrate the main results. Full article

The structural safety and performance of long-span bridges in coastal areas are significantly influenced by the wind field. Traditional univariate or simplified multivariate probabilistic models often fail to capture the multimodal and nonlinear dependencies among wind parameters, leading to inaccuracies in wind-induced risk assessment. This study proposes a novel joint probability density function framework for wind speed, wind direction, and wind attack angle, integrating a Dirichlet process mixture model (DPMM) for marginal distributions and a Regular Vine (R-Vine) copula for dependency modeling. The DPMM adaptively identifies the number of mixture components without presetting, effectively capturing multimodal and periodic characteristics of the wind field. The R-Vine copula flexibly models complex nonlinear dependencies among the three variables. A case study using field data from the Beikou Bridge demonstrates the capability to reveal seasonal wind patterns of the proposed model. By explicitly parametrizing the underlying wind regimes, the DPMM-based framework enables physically interpretable wind field decomposition. This provides direct support for probabilistic wind field modeling, supporting enhanced wind-resistant design and operational management of coastal long-span bridges. Full article

Celiac disease (CD) is an autoimmune enteropathy of the small intestine affecting genetically susceptible individuals, characterized by an aberrant immune response to gliadin and sustained IgA-driven inflammation. IgA exists in two main subclasses, IgA1 and IgA2, which differ in distribution and function, but their profile in CD remains poorly characterized. Circulating free light chains (FLCs) are markers of B-cell activation and immune dysregulation, yet their role in CD has not been fully explored. The aim of this study was to characterize IgA subclasses and FLC profiles in newly diagnosed celiac patients. We analyzed sera from 108 CD patients and 29 healthy controls, assessing conventional serological markers (anti-tissue transglutaminase and anti-endomysial antibodies), together with total IgA, IgA1, IgA2, and FLC levels using a turbidimetric method. CD patients exhibited higher total IgA levels and an increased IgA1/IgA2 ratio, alongside a decreased k/λ ratio; these differences remained significant after adjustment for age and sex. When combined in a multivariable logistic model, these biomarkers yielded an AUC of 0.827, suggesting that the parameters identified in the univariate analyses provide complementary, non-redundant information that jointly highlights a reorganization of the humoral immune response. Due to the limited sample size, our results need confirmation in larger cohorts. However, our findings suggest a reorganization of the IgA compartment in CD, with selective expansion of IgA1 and preferential λ light chain usage, highlighting coordinated alterations in the humoral immune response. The integration of such markers, potentially in combination with -omics approaches, may contribute to a more refined and less invasive characterization of celiac disease. Full article

Background/Objectives: Multiple sclerosis (MS) remains challenging to diagnose due to clinical and radiological overlap with mimicking conditions. The 2024 revisions of the McDonald criteria have incorporated the central vein sign (CVS) and paramagnetic rim lesions (PRLs) as magnetic resonance imaging (MRI) biomarkers to improve diagnostic specificity. This study assessed the prevalence and anatomical distribution of CVS and PRLs in patients with relapsing–remitting MS (RRMS). Methods: This cross-sectional study included 91 patients with RRMS diagnosed according to the 2017 McDonald criteria. MRI scans were obtained using 3T scanners, and T2-FLAIR and susceptibility-weighted angiography (SWAN) sequences were analyzed. CVS and PRLs were identified using established criteria. Patients were stratified by lesion count (<5, 5–9, ≥10), and lesions were categorized by anatomical location. Descriptive statistics, chi-square tests, and multivariable logistic regression adjusted for covariates were performed. Results: CVS was present in 69.2% of patients, while PRLs were identified in 29.7%. Both markers were more frequent in patients with higher lesion burden in univariate analysis. CVS prevalence increased significantly with lesion count (p < 0.001) and remained an independent predictor in multivariable logistic regression. PRL presence was associated with lesion count in univariate analysis but not after adjustment. Most CVS- and PRL-positive lesions were supratentorial and predominantly periventricular. No significant association was observed between CVS and PRL presence. Conclusions: CVS is a highly prevalent MRI feature in RRMS and independently associated with lesion burden, supporting its role as a diagnostically relevant imaging marker. PRLs were less prevalent and showed weaker independent associations. Full article

Lateritic nickel deposits exhibit complex weathering-driven geometries, strong vertical variability, and complex multivariate geochemical relationships. These characteristics challenge conventional deterministic resource modeling. This paper presents a unified probabilistic workflow for lateritic nickel mineral resource modeling that integrates lithology and grade simulation within a consistent geostatistical framework. The methodology combines unfolding, plurigaussian simulation, multivariate imputation of incomplete datasets, projection pursuit multivariate transformation (PPMT) for decorrelation, and conditional simulation using the Turning Bands algorithm. Application to an Indonesian lateritic nickel deposit demonstrates reproduction of lithological proportions, spatial continuity, marginal distributions, and complex multivariate relationships. The proposed workflow enables explicit quantification of geological and grade uncertainty, providing a basis for uncertainty assessment in recoverable resource estimation and supporting downstream applications such as resource classification and drillhole spacing analysis. Full article

This paper introduces a geometric framework for analyzing finite-energy signals observed with additive noise by representing them as points on statistical manifolds equipped with the Fisher–Rao metric. Each signal is associated with a parameter vector $\theta$, which defines a unique probability distribution $p\left(\mathbf{x}\right|\theta )$ on a statistical manifold. We propose a unified approach based on the normal multivariate model to describe a raw signal mixed with additive stationary noise. In the approach considered, the background noise is typically assumed to be stationary, whereas the unknown signal is regarded as deterministic. Leveraging tools from information geometry, we compute geodesic equations for the statistical manifolds. We re-derive known results regarding the multivariate normal models and extend them to the signal processing domain. We show that in some cases, the geodesic equations can be solved to obtain a closed-form expression of the Fisher–Rao distance. This expression corresponds to a minimum bound when the sub-manifold is not geodesic, revealing a fundamental geometric constraint in signal parameter estimation. We introduce the spectral distance function, which characterizes the influence of each spectral component of the signals on the Fisher–Rao distance. Our findings provide theoretical insights for signal clustering and machine learning applications, where geometric distances can characterize classification and estimation tasks. Full article

Background/Objectives: Sentinel lymph node biopsy is central to axillary staging in breast cancer, but conventional mapping often relies on radioisotopes and/or blue dye. Indocyanine green fluorescence has emerged as an alternative, although evidence for its use as a sole tracer in routine practice remains limited. This study evaluated the technical feasibility, lymph node yield, nodal metastasis detection, and short-term clinical outcomes of indocyanine green used as the only tracer for axillary staging in a consecutive single-centre cohort. Methods: This retrospective observational cohort study included 260 patients with histologically confirmed breast cancer who underwent axillary surgery at University Hospital Kaspela between 2024 and 2025 under an institutional protocol using indocyanine green as the sole tracer. Indocyanine green-guided mapping was attempted in all patients. For node-focused statistical analyses, a predefined complete-case–cohort of 230 patients was used. Descriptive analyses assessed axillary procedure distribution, lymph node yield, nodal metastasis, and postoperative outcomes. Exploratory multivariable logistic regression was performed to evaluate predictors of nodal metastasis. Results: Mapping was successful in 259/260 patients (99.6%). In the complete-case–cohort, sentinel lymph node biopsy was performed in 166/230 patients (72.2%), targeted axillary dissection in 4/230 (1.7%), and axillary lymph node dissection in 60/230 (26.1%). Median overall lymph node yield was 4 (IQR 3–7), but this pooled value reflected heterogeneous axillary procedures and should not be interpreted as sentinel node yield alone. In the clinically node-negative upfront SLNB subgroup, median lymph node yield was 4 (IQR 2.75–5), and nodal metastasis was identified in 22/112 patients (19.6%). Overall, nodal metastasis was identified in 58/230 patients (25.2%), with a median of 2 metastatic nodes (IQR 1–3) among nodal-positive cases. Reoperation for axillary lymph node dissection occurred in 14/230 patients (6.1%). In exploratory multivariable analysis, suspicious biopsied-positive nodes (OR 12.85, 95% CI 3.98–41.52), suspicious non-biopsied nodes (OR 15.58, 95% CI 3.44–70.59), and neoadjuvant therapy (OR 0.31, 95% CI 0.11–0.87) were associated with nodal metastasis; these findings should be interpreted cautiously given the expected clinical relationship between preoperative nodal suspicion and nodal positivity, and the limited number of nodal-positive events. Conclusions: Indocyanine green used as a sole tracer demonstrated high technical feasibility within a heterogeneous real-world axillary staging workflow in this single-centre cohort. These findings should be interpreted as implementation-focused feasibility data rather than formal diagnostic validation, given the retrospective design, heterogeneous case mix, and absence of an internal comparator. Full article

Background: The study aimed to evaluate whether routine hematological parameters can differentiate attack and remission phases in children with Familial Mediterranean Fever (FMF) and to identify accessible biomarkers for disease activity monitoring. Methods: This retrospective study included pediatric FMF patients diagnosed according to Tel Hashomer, Livneh, or Yalçınkaya criteria at Aydın Adnan Menderes University between April 2000 and April 2020. Patients with complete blood count data available for both attack and remission phases were analyzed. Hematological parameters included leukocyte, neutrophil, lymphocyte, and platelet counts, plateletcrit (PCT), mean platelet volume (MPV), and platelet distribution width (PDW). Paired comparisons were performed using appropriate statistical tests. Independent predictors of disease phase were identified using a multivariate mixed-effects logistic regression model. Results: Eighty-seven patients (mean age at diagnosis 7.1 ± 3.6 years) were included. Neutrophil counts were significantly higher during attacks than remission (p < 0.001). Although lymphocyte counts were not significant in univariate analysis, higher lymphocyte concentration was independently associated with remission (OR = 1.71, 95% CI: 1.19–2.45). PDW was significantly higher during remission and independently predicted remission status (OR = 1.92, 95% CI: 1.30–2.85). PCT and MPV were not significant predictors. Conclusions: Neutrophil count, lymphocyte count, and PDW may represent potential and accessible markers associated with FMF attack and remission phases in pediatric patients. Full article

Background and Objectives: Paramedian cervical interlaminar epidural steroid injection (CESI) is commonly used for cervical radicular pain and is considered safer than the transforaminal approach. However, its clinical effectiveness may be influenced by contrast distribution patterns, although these may not fully reflect actual drug delivery. This study aimed to evaluate the association between needle trajectory, foraminal or periradicular contrast distribution patterns, and short-term pain reduction following paramedian cervical interlaminar CESI. Materials and Methods: This single-center retrospective study included 109 patients who underwent paramedian cervical interlaminar CESI. Needle trajectory was classified as inward or outward. Contrast distribution was graded based on anteroposterior (AP) spread patterns. Pain intensity was assessed using a numeric rating scale (NRS) at baseline and 2 weeks after the procedure. Group comparisons were performed using Welch’s t-test and chi-square or Fisher’s exact test, as appropriate. Effect sizes were calculated using Cohen’s d and η². Multivariable linear regression analysis was performed adjusting for age, sex, baseline NRS, and target level. Results: The outward trajectory group demonstrated a significantly higher proportion of Grade 2 contrast spread compared to the inward group (69.8% vs. 8.9%, p < 0.001). Higher AP contrast spread grades were associated with greater pain reduction (β = 0.83, 95% CI: 0.44–1.22, p < 0.001; η² = 0.14). In addition, patients in the outward trajectory group showed greater NRS reduction than those in the inward group (2.96 vs. 1.71, mean difference: 1.25, 95% CI: 0.74–1.76, p < 0.001; Cohen’s d = 0.96). In multivariable analysis, needle trajectory remained significantly associated with pain reduction, whereas AP contrast spread grade was not independently associated. Conclusions: Needle trajectory was associated with contrast distribution patterns and short-term pain reduction following paramedian cervical interlaminar CESI. An outward-directed trajectory was associated with greater foraminal or periradicular contrast spread and greater pain reduction. These findings suggest that needle trajectory may represent a clinically relevant procedural factor influencing clinical outcomes. Full article

Background: Neurological disorders are a leading cause of disability worldwide, placing increasing strain on healthcare systems. In Eastern Europe, and specifically Bulgaria, there is a significant lack of granular data regarding how ambulatory neurology services are utilized and how clinical workloads are distributed across different diagnostic groups. Objective: In this study, we aimed to analyze the clinical workload, demographic patterns, and diagnostic distribution within a single-center ambulatory neurology setting in Bulgaria, while identifying the primary determinants of patient age stratification. Methods: We conducted a retrospective observational study of 518 consecutive clinical encounters recorded over a one-year period in a specialized outpatient neurology clinic. Data on age, gender, visit type (ambulatory vs. dispensary), and ICD-10 diagnostic groups were analyzed. Inferential analyses included a one-way ANOVA for age differences and multivariable linear regression to identify independent predictors of age patterns, with age modeled as a continuous variable. Results: The clinical workload was highly concentrated, with spine-related disorders accounting for over 40% of all visits, and primary consultative examinations were the predominant service type (65.4%). Statistical analysis revealed significant age differences across diagnostic categories (p < 0.001), with neurodegenerative and cerebrovascular diseases associated with the highest mean age, while spine and headache syndromes involved significantly younger populations. Multivariable modeling confirmed that diagnostic category is the sole independent determinant of age distribution (p < 0.001), whereas gender and visit type showed no significant independent associations. Conclusions: Ambulatory neurology utilization in this setting is characterized by a high-turnover primary consultation model and a heavy concentration of musculoskeletal neurological conditions. These findings suggest that outpatient neurology functions as a critical diagnostic filter and pain management hub. The study underscores the need for diagnosis-specific clinical pathways and targeted resource allocation to optimize service efficiency and improve long-term management of chronic neurological morbidity in a public insurance-driven framework. Full article

Background: Gallbladder carcinoma (GBC) represents one of the most aggressive malignancies of the hepatobiliary system, evolving along a continuum from chronic inflammation to preneoplastic lesions and invasive cancer. This progression is frequently associated with gallstones and chronic cholecystitis and shares common pathogenic mechanisms with systemic inflammatory and metabolic disorders. Despite its relatively low incidence, GBC is characterized by poor prognosis, largely due to late-stage diagnosis and limited understanding of its molecular underpinnings. Methods: We conducted an observational study including 60 adult patients with radiologically suspected gallbladder cancer (GBC). Patients with disseminated disease, ongoing oncologic treatment, or synchronous malignancies were excluded. Fasting venous blood samples were collected to evaluate tumor markers and biochemical parameters, including carcinoembryonic antigen (CEA) and carbohydrate antigen CA 19-9. Surgical specimens were analyzed histopathologically and staged according to the European Society for Medical Oncology TNM classification system. Statistical analysis was performed using SPSS software (version 26.0), with appropriate parametric or non-parametric tests applied based on data distribution, and a p-value < 0.05 considered statistically significant. Results: Based on histological findings, patients were stratified into benign gallbladder disease (GBD) and GBC groups. CA 19-9 demonstrated higher mean serum levels with lower variability compared to CEA, suggesting superior sensitivity and diagnostic stability for gallbladder adenocarcinoma. In contrast, CEA levels exhibited greater fluctuation, limiting its reliability as a standalone biomarker. Importantly, the combined use of CA 19-9 and CEA improved diagnostic accuracy, supporting a multimarker approach for better clinical stratification. Our findings highlight the diagnostic value of CA 19-9 as a robust biomarker in GBC and support the integration of combined biomarker panels. Beyond tumor markers, the study identified a strong interplay between systemic inflammation and metabolic comorbidities, with obesity and hypertension significantly associated with chronic gallbladder pathology, and diabetes mellitus contributing to increased risk of acute inflammatory episodes. Elevated inflammatory markers, leukocytosis, and cholestatic enzyme alterations further supported the presence of a systemic inflammatory milieu. Multivariate analysis revealed that C-reactive protein (CRP), as a marker of systemic inflammation, was significantly influenced by a combination of clinical and biochemical variables, including age, hemoglobin, hypertension, amylase, CA 19-9, and CEA, explaining over 50% of its variability and up to 85% in advanced fibrotic changes. Additionally, platelet counts were significantly reduced in adenocarcinoma and correlated specifically with CA 19-9 levels, suggesting a potential link between tumor burden, inflammation, and platelet dynamics. Conclusions: Therefore, the observed associations between chronic inflammation, metabolic dysregulation, and tumor marker expression suggest a potential link between gallbladder carcinogenesis and systemic cardiometabolic pathways, opening new perspectives for early detection and targeted therapeutic strategies. Full article

This study examines the determinants of energy consumption in South Africa over the period 1980–2023 using a multivariate time-series framework. Unlike conventional studies that focus primarily on the energy–growth nexus, this analysis incorporates financial development, industrialization, and population growth to provide a more comprehensive understanding of energy demand dynamics. The Autoregressive Distributed Lag (ARDL) approach is employed to estimate both short-run and long-run relationships. Unit root tests confirm that all variables are integrated of order one, justifying the application of the ARDL bounds testing approach. The results reveal the existence of a stable long-run relationship between energy consumption and its determinants. Industrialization and population growth emerge as the most significant drivers of energy demand in both the short and long run, reflecting South Africa’s energy-intensive economic structure and rising demographic pressures. Financial development is found to have a positive and statistically significant effect, suggesting that improved access to credit stimulates energy consumption through increased investment and economic activity. In contrast, economic growth exhibits a positive but statistically insignificant long-run effect, indicating partial decoupling between output growth and energy demand. The error correction term is negative and statistically significant, confirming convergence to long-run equilibrium. Causality analysis further indicates that energy consumption is primarily driven by macroeconomic factors rather than acting as a leading indicator. The findings underscore the importance of industrial energy efficiency, population-responsive energy planning, and targeted financial support for sustainable energy investment. This study contributes to the literature by providing a comprehensive, country-specific analysis and offers policy-relevant insights for enhancing energy security and supporting sustainable economic development in South Africa. Full article