伊兹密尔KâtipÇelebi大学

Recent advances in Kolmogorov–Arnold Networks (KANs) have shown strong potential for functional representation learning; however, existing formulations remain limited in their ability to provide explicit geometric interpretability, curvature control, and deformation-aware adaptation for biomedical image analysis. This paper introduces q-FunKAN, a geometry-aware Functional Kolmogorov–Arnold Network that integrates learnable Lupaş q-Bézier inner functions and q-Hermite spectral parameterizations within a unified geometric–spectral framework for biomedical image enhancement and segmentation. The central novelty of the proposed model lies in embedding a learnable deformation parameter q into the KAN functional space, enabling curvature-adaptive modulation of local anatomical structures while preserving global smoothness through spectral regularization.The proposed framework combines three complementary mechanisms: Bézier-based control-point parameterization for interpretable local deformation, q-Hermite spectral expansion for stable global representation, and topology-preserving deformation regularization for anatomically plausible enhancement and segmentation. This design allows q-FunKAN to explicitly balance local boundary precision and global structural consistency, providing a transparent alternative to highly parameterized convolutional and transformer-based models.Extensive experiments on five benchmark MRI datasets, including BRATS 2021, CHAOS, fastMRI, IXI, and a controlled synthetic phantom dataset, demonstrate the effectiveness of the proposed framework. Compared with strong convolutional, transformer-based, restoration-oriented, and KAN-based baselines, q-FunKAN achieves consistent improvements in image fidelity, perceptual quality, and segmentation accuracy, including gains of up to (+1.3) dB PSNR, (+1.0%) Dice, and (-0.004) LPIPS over leading competing models. Ablation studies further confirm that learnable q-adaptivity, Bézier geometric modeling, Hermite spectral regularization, and Jacobian-based topology preservation make complementary contributions to performance and stability. Qualitative analyses show sharper anatomical boundaries, reduced artifacts, and interpretable q-heatmaps aligned with curvature-sensitive regions.By bridging q-calculus, geometric approximation theory, and functional neural representation learning, q-FunKAN establishes a mathematically grounded, interpretable, and geometry-aware framework for biomedical image enhancement and segmentation.

Tb3+-activated LiCa4O(BO3)(3) (LiCBO) borates are promising phosphors for high-power near-UV LEDs and optical thermometry, but charge imbalance and lattice defects limit their thermal stability and efficiency. This work reports a comprehensive structural-optical study of LiCBO:Tb3+ phosphors with K+/Na+ charge-compensating co-dopants synthesized by combustion reaction. X-ray diffraction and Rietveld refinement show that all compositions remain single-phase LiCBO, with Tb3+ preferentially substituting Ca2+ sites while K+/Na+ ions act as charge compensators, inducing only marginal, monotonic changes in lattice parameters. Multi-model XRD line-broadening analysis reveals that alkali co-doping increases crystallite size from similar to 60 to similar to 90 nm and reduces microstrain and dislocation density, indicating defect suppression through charge-compensated lattice engineering. FTIR/Raman spectroscopy confirms preservation of the mixed BO3/BO4 framework, with subtle band shifts and increased I(BO4)/I(BO3) ratios evidencing local network reorganization rather than phase segregation. Under 377 nm excitation, LiCBO:Tb3+ exhibits intense green D-5(4) -> F-7(5) emission at 542 nm with an optimum Tb3+ content of x = 0.05, above which concentration quenching proceeds via multipolar Tb3+-Tb3+ interactions (R-c approximate to 10.6 & Aring;). K+/Na+ co-doping boosts the green emission by up to similar to 2-2.25 & times; at y = 0.01, mainly by suppressing non-radiative defect channels and tuning local symmetry, as supported by biexponential lifetime shortening and increased Judd-Ofelt Omega(2) parameters. Temperature-dependent PL (300-550 K) demonstrates robust thermal stability, retaining similar to 40-45% of the initial 542 nm intensity at 423-450 K with a single activation energy E-a approximate to 0.33 eV. Finally, a fluorescence intensity ratio thermometer based on the 680/542 nm Tb3+ emissions delivers a maximum relative sensitivity of similar to 1.3% K-1 near 500 K, demonstrating competitive performance among single-center Tb3+-activated phosphors for high-temperature operation. Overall, K+/Na+-assisted charge-compensated lattice engineering is shown to simultaneously enhance green emission efficiency, thermal robustness, and luminescent thermometry performance in LiCBO:Tb3+ phosphors.

Four novel bioactive boron containing compounds (BCCs) were prepared by the reactions of quercetin and various boronic acids using a Dean-Stark technique to remove the H2O formed as a result of the chemical reaction. The antiepileptic properties of the bioactive BCCs also were investigated under suitable conditions. For this aim, the effect of the BCCs on the enzyme activities of carbonic anhydrase I and II isoenzymes (hCA I and hCA II) were evaluated spectrophotometrically. The bioactive BCCs have been investigated for their potential anticancer properties against PC-3, Du-145, and HEK-293 T cell lines utilizing the WST-1 assay method. Notably, the IC50 values of both boron compounds against the healthy control HEK-293 T cells were significantly higher compared to those observed in cancer cells. Lastly, bioactive boron containing compounds were examined through Gaussian calculations employing the B3LYP, HF, and M062X methods on the 6–31 + + g(d,p) basis set. Computational molecular docking was performed on specific proteins and ADME/T calculations were conducted to analyze the effects and interactions of these compounds at human metabolism.

This article examines the effects of population ageing on the composition of government spending in 25 European Union member states from 1995 to 2023. Empirical evidence indicates that demographic ageing leads to shifts in government spending priorities. In particular, government spending tends to increase on social protection, general public services, health, and defence, while decreasing on housing and community amenities, environmental protection, and education. These results suggest that demographic ageing contributes to a reallocation of government spending toward age-related functions, accompanied by relative reductions in other areas. Overall, the findings highlight the potential structural implications of population ageing for fiscal sustainability and intergenerational equity, emphasizing the importance of public policies that are adaptable to long-term demographic changes.

Spiro-cyclotriphosphazenes such as 2,2-dichloro-4,4,6,6-bis[spiro(2',2”-dioxy-1',1”-biphenyl)]cyclotriphosphazene (DPP) and 2,2,4,4-tetrachloro-6,6-[spiro(2',2”-dioxy-1',1”-biphenyl)]cyclotriphosphazene (BPP) are well-established intermediates for functional phosphazene derivatives. However, their intrinsic optical and electronic properties have not been systematically explored under varying experimental conditions. In this work, DPP and BPP were synthesized and characterized to elucidate the correlation between structural parameters and photophysical behavior. A complementary experimental approach was employed: DPP optical properties were examined in solution as a function of molarity, while BPP properties were investigated in the solid state as a function of film thickness. This strategy enables a comparative evaluation of how intermolecular interactions and structural topology influence optical behavior. UV–Vis measurements revealed band-gap narrowing from 3.904 to 3.805 eV for BPP and from 3.921 to 3.830 eV for DPP, accompanied by red shifts. DFT calculations (B3LYP/6—31G(d,p)) reproduced the relative trends, with HOMO–LUMO gaps of 1.91 eV (BPP) and 0.92 eV (DPP); although absolute values differ from experiment, the calculations correctly predict the relative absorption onsets and tunable optical behavior. Molecular electrostatic potential (MEP) maps and conceptual DFT descriptors indicate that BPP is harder and more electrophilic, while DPP is softer and more polarizable, consistent with red-shifted absorption. These findings highlight the intrinsic optical robustness of both compounds and demonstrate that parameters such as film thickness, solution molarity, and ring topology can be used to tailor optoelectronic properties. The study establishes BPP and DPP as promising candidates for UV–blue optoelectronic devices, photodetectors, and wide-bandgap photonic materials.