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Clinical and Functional Heterogeneity of COPD Phenotypes: A Multicenter Study from Turkey (DIPTUR Study)
No full textBackground and Objectives: Chronic obstructive pulmonary disease (COPD) is heterogeneous, and phenotype-based classification may better capture differences in clinical burden and healthcare needs beyond standard GOLD categories. We aimed to describe the distribution of GesEPOC COPD phenotypes in Turkey and compare their demographic, clinical, functional, radiological, treatment, and healthcare utilization profiles. Materials and Methods: DIPTUR was a multicenter, observational, cross-sectional study conducted prospectively in 26 centers across 17 Turkish cities (October 2019–June 2021). Stable COPD patients (≥40 years; post-bronchodilator FEV1/FVC < 0.7) without exacerbation or major treatment modification within the previous four weeks were enrolled consecutively. Phenotypes were assigned per GesEPOC: exacerbator with emphysema (EE), exacerbator with chronic bronchitis (ECB), asthma–COPD overlap (ACO), and non-exacerbator (NE). Frequent exacerbators were defined as patients who experienced two or more exacerbations during the 12 months preceding enrollment, based on medical records and patient reports. Results: Among 894 patients, phenotype distribution was NE 44.1%, ECB 26.2%, EE 20.5%, and ACO 9.3%. Male predominance was observed across groups (80–89%; p = 0.006). Active smoking was most frequent in ECB (37.6%; p < 0.001), and BMI was lowest in EE (p < 0.001). Comorbidity patterns differed, with hypertension (p < 0.001), diabetes mellitus (p = 0.029), and heart failure (p < 0.001) most prevalent in ECB. Pulmonary function (FEV1 and FVC) was lowest in EE (both p < 0.001), and severe airflow limitation (GOLD III–IV) was most common in EE and ECB (p < 0.001). Dyspnea (mMRC ≥ 2) was more frequent in EE/ECB than in ACO/NE (p < 0.001). Emphysematous changes on thoracic CT predominated in EE (91.7%; p < 0.001). Long-term oxygen therapy was most common in EE (32.4%; p < 0.001). Emergency admissions, hospitalizations, and total length of stay were markedly higher in EE and ECB than in ACO and NE (all p < 0.001). Conclusions: COPD phenotypes in Turkey show substantial heterogeneity in clinical, functional, radiological, and utilization domains. Exacerbator phenotypes—particularly EE and ECB—represent higher-burden groups, supporting phenotype-oriented management and closer monitoring beyond GOLD classification
Investigation of Antibacterial Activities and Cytotoxicity of Bee Pollen Ethanol Extract: Determination of Phenolic Acid and Sugar Contents by Using Chromatographic Methods
No full textIn this study, phenolic acid content of bee pollen ethanol extract was investigated using TLC and LC-MS-MS and HPLC-RID methods, and vanillic acid, caffeic acid, gallic acid, and ellagic acid were identified. Antimicrobial activity of bee pollen ethanol extract mixture was screened against Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) species by using TLC bioautography, minimum inhibitory concentrations (MIC), and disc diffusion methods. Pollen extract showed antibacterial activity against S. aureus and E. coli; disc diffusion test results showed 16 and 10 mm inhibition zone at 6000 μg/mL concentration. Caffeic acid and gallic acid showed inhibitory action against both S. aureus and E. coli in TLC bioautography studies. Glucose (3.78 ± 0.14 mg/mL), fructose (6.56 ± 0.17 mg/mL), and sucrose (0.13 ± 0.02 mg/mL) were detected as main carbohydrates in pollen extract. Extract did not show significant cytotoxic effect at all tested concentrations on HEK-293 cells
Batalin–Fradkin–Vilkovisky quantization of Einstein gravity with off-diagonal solutions encoding Hořava type generating functions
No full textWe develop and apply the Batalin–Fradkin–Vilkovisky (BFV) formalism for the covariant quantization of generic off-diagonal solutions of the Einstein equations in general relativity (GR). In the classical regime, such nonholonomic configurations are formulated entirely within GR and are characterized by nonlinear symmetries of generating functions, running cosmological constants, integration functions, and effective matter sources. These constructions are further extended to quantum gravity (QG) models involving effective local Lorentz symmetry violations and anisotropic scaling, as realized in Hořva–Lifshitz (HL)-type theories. The classical geometric framework is formulated on Lorentz manifolds endowed with nonholonomic 2+2 and 3+1 splitting structures and subsequently generalized to quantum configurations determined by HL-type generating functions. The 2+2 dyadic splitting, incorporating connection distortions, provides a systematic method for constructing exact and parametric classical and quantum solutions described by generating functions and effective sources depending on all spacetime coordinates, physical constants, and anisotropic scaling or deformation parameters. The complementary 3+1 splitting allows for a consistent implementation of the BFV quantization procedure. We demonstrate the renormalizability of off-diagonal quantum HL-type deformations of GR. The resulting classical and quantum nonholonomic BFV models represent viable candidates for asymptotically free theories of gravity and may provide a mechanism for resolving unitarity issues in QG. In appropriate classical limits, the framework reproduces physically relevant off-diagonal GR solutions with or without locally anisotropic scaling, offering potential applications to nonlinear classical and quantum phenomena in accelerating cosmology and dark energy and dark matter physics
Evaluation of the relationship between the 2D:4D ratio, fine hand motor skills, and anatomy practical examination performance in first-year medical students.
No full textAdvanced Hermite-Hadamard-Mercer Type Inequalities with Refined Error Estimates and Applications
No full textThe purpose of this research is to develop a set of Hermite–Hadamard–Mercer-type inequalities that involve different types of fractional integral operators such as classical Riemann–Liouville fractional integral operators. Furthermore, some fractional integral inequalities are obtained for three-times differentiable convex functions with respect to the right-hand side of the Hermite–Hadamard–Mercer-type inequality. Moreover, several new results regarding Young’s inequality, bounded function and L-Lipschitzian function are deduced. The paper presents additional remarks and comments on the results to make sense of them. To illustrate the key findings, graphical representations are provided, and applications involving special means, midpoint formula, q-digamma function and modified Bessel function are presented to demonstrate the practical utility of the derived inequalities
Ventricle Detection Case Study: Comparison of Current Deep Learning Architecture Performances
No full textMulti-element analysis of archaeological limestone artifacts: A data-level matrix correction approach
No full textElemental analysis of carbonate-rich heritage materials is often subject to strong matrix effects caused by high calcium content, which can lead to systematic underestimation of some major and trace elements, including rare earth elements (REEs), by ICP-OES and ICP-MS. This study develops a practical analytical strategy tailored to archaeological limestone artifacts, combining microwave-assisted digestion with a data-level, element-specific matrix correction based on certified reference materials (CRMs). Concentrations obtained by external calibration were empirically adjusted using correction factors derived from the ratio of standard addition to external calibration results for the CRMs NIST 1d and NCS DC 73306. This approach brought all determined element concentrations into statistical agreement with the certified values. The workflow was applied to 69 limestone figurines from the Emecik Apollo Sanctuary (T & uuml;rkiye) that were previously attributed to Cypriot sources. After matrix correction, multivariate statistical analysis of the major, trace, and REE data identified three distinct geochemical clusters, consistent with the exploitation of at least three Cypriot limestone formations. The method is minimally destructive, time-and cost-efficient, and suitable for large archaeological assemblages, providing more accurate compositional data that support reliable provenance interpretations and establish a solid geochemical basis for reconstructing raw material procurement strategies for limestone votive figurines in the ancient Eastern Mediterranean. (c) 2026 Elsevier Masson SAS. All rights are reserved, including those for text and data mining, AI training, and similar technologies
New Approach to Fractional Milne-type Inequalities
No full textIn the literature, there are several Milne-type inequalities by using the convex functions. In this study, we establish the upper and below bounds for fractional Milne-type inequalities by using functions whose second derivatives are bounded instead of convex functions. Moreover, we present new inequalities for Riemann integrals as special cases. We also present an example and a graph to illustrate the main results
Depth Matters: Geometry-Aware RGB-D-Based Transformer-Enabled Deep Reinforcement Learning for Mapless Navigation
No full textAutonomous navigation in unknown environments demands policies that can jointly perceive semantic context and geometric safety. Existing Transformer-enabled deep reinforcement learning (DRL) frameworks, such as the Goal-guided Transformer Soft Actor-Critic (GoT-SAC), rely on temporal stacking of multiple RGB frames, which encodes short-term motion cues but lacks explicit spatial understanding. This study introduces a geometry-aware RGB-D early fusion modality that replaces temporal redundancy with cross-modal alignment between appearance and depth. Within the GoT-SAC framework, we integrate a pixel-aligned RGB-D input into the Transformer encoder, enabling the attention mechanism to simultaneously capture semantic textures and obstacle geometry. A comprehensive systematic ablation study was conducted across five modality variants (4RGB, RGB-D, G-D, 4G-D, and 4RGB-D) and three fusion strategies (early, parallel, and late) under identical hyperparameter settings in a controlled simulation environment. The proposed RGB-D early fusion achieved a 40.0% success rate and +94.1 average reward, surpassing the canonical 4RGB baseline (28.0% success, +35.2 reward), while a tuned configuration further improved performance to 54.0% success and +146.8 reward. These results establish early pixel-level multimodal fusion (RGB-D) as a principled and efficient successor to temporal stacking, yielding higher stability, sample efficiency, and geometry-aware decision-making. This work provides the first controlled evidence that spatially aligned multimodal fusion within Transformer-based DRL significantly enhances mapless navigation performance and offers a reproducible foundation for sim-to-real transfer in autonomous mobile robots
Comparison of the Radiomics Features of Normal-Appearing White Matter in Persons with High or Low Perivascular Space Scores
No full textThe clinical significance of perivascular spaces (PVS) remains controversial. Radiomics refers to the extraction of quantitative features from medical images using pixel-based computational approaches. This study aimed to compare the radiomics features of normal-appearing white matter (NAWM) in patients with low and high PVS scores to reveal microstructural differences that are not visible macroscopically. Adult patients who underwent cranial MRI over a one-month period were retrospectively screened and divided into two groups according to their global PVS score. Radiomics feature extraction from NAWM was performed at the level of the centrum semiovale on FLAIR and ADC images. Radiomics features were selected using Least Absolute Shrinkage and Selection Operator (LASSO) regression during the initial model development phase, and predefined radiomics scores were evaluated for both sequences. A total of 160 patients were included in the study. Radiomics scores derived from normal-appearing white matter demonstrated good discriminative performance for differentiating high vs. low perivascular space (PVS) burden (AUC = 0.853 for FLAIR and AUC = 0.753 for ADC). In age- and scanner-adjusted multivariable models, radiomics scores remained independently associated with high PVS burden. These findings suggest that radiomics analysis of NAWM can capture subtle white matter alterations associated with PVS burden and may serve as a non-invasive biomarker for early detection of microvascular and inflammatory changes