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Landslide susceptibility classification using multi hive artificial bee colony programming: A novel symbolic regression framework
No full textLandslides, highly destructive natural hazards, threaten mountainous regions impacted by rainfall, seismic activity, and human actions. Machine learning (ML) techniques for landslide susceptibility mapping (LSM) often face challenges like interpretability, overfitting, and handling high-dimensional data. This study presents Multi Hive Artificial Bee Colony Programming (MHABCP), a novel symbolic regression framework merging swarm intelligence and multi-tree programming to create interpretable, robust LSM models. A key feature is the integration of the Relative Outlier Cluster Factor method for outlier detection, enhancing data quality and model stability. Tested against Multi Gene Genetic Programming (MGGP) using a dataset from Varto, eastern Turkey, with 18 environmental and topographic factors, MHABCP achieved 90.57 % test accuracy and a 90.51 % F1-score, surpassing MGGP in all metrics while remaining interpretable. MHABCP also showed consistency across 100 runs and better classified landslide-prone areas, offering a scalable, explainable solution for disaster risk reduction and geospatial planning
Multifunctional Bioactivities of Ellagic Acid-Based Hybrid Cu, Zn, and Co Microflowers: Antioxidant, Anti-AChE, Anticancer, and Antibacterial Effects
No full textHUNTING COOPERATION AND GESTATION DELAY IN A PREY-PREDATOR MODEL WITH FRACTIONAL DERIVATIVE
No full textPredator-prey dynamics are central to ecological modeling, with the Lotka-Volterra framework serving as a foundational tool for studying these interactions. In this study, we propose a novel fractional-order predator-prey model incorporating cooperative hunting and gestation delays to better capture the complexities of real-world ecosystems. The cooperative hunting mechanism enhances predator efficiency, while gestation delay accounts for the time required for biomass transfer from prey to predator reproduction. Additionally, we integrate fractional derivatives to introduce memory effects, allowing the system to retain past influences on population dynamics. We establish the dynamical analysis of the model. Through numerical simulations, we demonstrate the interplay between cooperation, delay, and memory effects, revealing rich dynamical behaviors
PANORAMİK RADYOGRAFTA İDİOPATİK OSTEOSKLEROZUN FRAKTAL ANALİZİ
No full textAmaç: Çenelerin idiyopatik osteosklerozu (IO); lokalize, nonekspansif, homojen radyoopasitelerdir ve genellikle asemptomatiktir. Histopatolojik olarak kemik iliği boşluğu içermeyen, yoğun kalsifiye dokulardır. Fraktal analiz (FA), kemiğin mikro yapısal olarak değerlendirilmesine olanak sağlayan bir yöntemdir. Fraktal Boyutta (FB) artış, kemiğin yoğun olduğunu, azalma ise gözenekli olduğunu gösterir. Bu çalışmanın amacı çene kemiklerinde idiopatik osteoskleroz saptanan bireylerin trabeküler kemik yapılarının FA metoduyla değerlendirilmesidir.Yöntem: Kliniğimize başvuran bireylerin panoramik radyografları restrospektif olarak tarandı, 44 bireyde idiyopatik osteoskleroz odak saptanan trabeküler yapı, aynı bireyin midsagital hatta göre simetrik normal trabeküler yapı ile FA yöntemiyle karşılaştırıldı. Panoramik radyograflar üzerinde ölçümler için ilgili alan (İA) manuel olarak seçildi. FB, ImageJ programı ile hesaplandı. Ölçümler Ağız, Diş ve Çene Radyolojisi ana bilim dalında görev yapan iki araştırma görevlisi tarafından yapıldı ve her iki ölçümün ortalaması istatistiksel analiz için kullanıldı. İstatistiksel analizler IBM SPSS Statistics 30.0 yazılımı kullanılarak yapıldı. İstatistiksel anlamlılık düzeyi p<0,05 olarak kabul edildi.Bulgular: Osteosklerotik kemiğe ve normal kemiğe ait FB ölçümleri sonucuna göre, iki grup arasında istatistiksel olarak anlamlı bir fark vardı. (p<0.05). Osteosklerotik grubun İA’daki FB ölçümlerinin ortalaması, kontrol grubuna göre daha yüksekti. Sonuç: FB değerinin yüksek olması kemik trabekülasyon yoğunluğu ile doğru orantılı bir veridir. Bu çalışmada osteosklerotik odağı bulunan bireylerde İA’da FB’de anlamlı artış gözlenmiştir. Kemik dokusunda değişikliklere yol açabilen durumlarda kemikte trabekülasyon artışlarını/kayıplarını değerlendirmede FA faydalı bir yöntem olarak değerlendirilebilir. Anahtar Kelimeler: İdiopatik osteoskleroz, Fraktal analiz, Panoramik radyografiPurpose: Idiopathic osteosclerosis (IO) of the jaws is localized, non-expansive, homogeneous radiopacity and is usually asymptomatic. Histopathologically, it is a densely calcified tissue that does not contain bone marrow space. Fractal analysis (FA) is a method that allows microstructural evaluation of bone with fractal geometric features. An increase in Fractal Dimension (FD) indicates that the bone is dense, while a decrease indicates that it is porous. The aim of this study is to evaluate the trabecular bone structures of individuals with idiopathic osteosclerosis in the jaw bones using the FA method.Materials&Method: Panoramic radiographs of individuals who applied to our clinic were scanned retrospectively, and the trabecular structure in which idiopathic osteosclerosis foci were detected in 44 individuals was compared with the symmetrical normal trabecular structure of the same individual according to the midsagittal line using the FA method. The area of interest (IA) was manually selected for measurements on panoramic radiographs. FD was calculated with the ImageJ program. The measurements were made by two research assistants working in the department of Oral, Dental and Maxillofacial Radiology and the average of both measurements was used for statistical analysis. Statistical analyses were performed using IBM SPSS Statistics 30.0 software. The statistical significance level was accepted as p<0.05. Results: According to the FD measurements of osteosclerotic bone and normal bone, there was a statistically significant difference between the two groups (p<0.05). The average of FD measurements in IA of the osteosclerotic group was higher than the control group.Conclusion: High FD value is a data directly proportional to bone trabeculation density. In this study, a significant increase in FD in IA was observed in individuals with osteosclerotic focus. FA can be considered as a useful method in evaluating trabeculation increases/losses in bone in cases that may cause changes in bone tissue.Keywords: Idiopathic osteosclerosis, Fractal analysis, Panoramic radiography</p
Synthesis and optical characterization of ZnO nanowires for nanolaser applications
No full textZnO nanowires were successfully synthesized via a low-temperature hydrothermal method. Comprehensive structural and morphological characterization confirmed the formation of high-quality nanowires. X-ray diffraction (XRD) analysis revealed a pure, highly crystalline hexagonal wurtzite structure with a strong preferential growth orientation along the (002) plane. Field emission scanning electron microscopy (FE-SEM) showed uniform nanowires with average diameters and lengths of 80-120 nm and similar to 2-3 mu m, respectively. For optical studies, the nanowires were dispersed in chloroform and deposited onto silica substrates via spin coating. Photoluminescence (PL) spectroscopy at room temperature exhibited a strong near-band-edge (NBE) emission peak at similar to 380 nm and a broad visible deep-level emission (DLE) band centered at similar to 650 nm, associated with oxygen vacancies. Under optical pumping with a mode-locked Ti: sapphire laser (266 nm, 150 fs pulses), the samples exhibited amplified spontaneous emission (ASE) at 393 nm with a remarkably low threshold of 28.3 W/cm(2). These outstanding optical properties, particularly the low ASE threshold and strong excitonic emission, demonstrate the significant potential of the synthesized ZnO nanowires as gain media for efficient ultraviolet nanolasers and other integrated photonic devices
Modification Procedures for Chronic Total Occlusion Percutaneous Coronary Intervention: Insights From the PROGRESS-CTO Registry
No full textBackground: CTO-ARC (Chronic Total Occlusion Academic Research Consortium) defines CTO modification procedures (previously called investment procedures) as intentional balloon dilatation (diameter ≥ 2.0 mm) of the entire CTO, including the proximal and distal caps and the CTO body. Aims: The aim of this study is to compare the outcomes of repeat CTO PCI between patients who underwent lesion modification during the initial failed procedure and those who did not. Methods: We analyzed the association of CTO modification with the baseline clinical and angiographic characteristics and outcomes of 2829 patients, with a total of 2869 CTOs who underwent CTO percutaneous coronary intervention (PCI) after a previously failed attempt. Results: CTO modification was performed in 600 of 2869 CTOs (20.9%) that underwent a repeat PCI attempt. CTOs that underwent modification had a higher prevalence of blunt/no stump (63.9% vs. 54.5%, p < 0.001), moderate/severe calcification (59.4% vs. 48.5%, p < 0.001), and moderate/severe proximal tortuosity (43.6% vs. 30.4%, p < 0.001). They also had longer length (38 vs. 31 mm, p < 0.001) and higher J-CTO (3.69 vs. 3.21, p < 0.001) score. There was no statistically significant difference in technical (84.1% vs. 85.4%, p = 0.478) or procedural (82.7% vs. 84.2%, p = 0.403) success or major adverse cardiac events (MACE, 1.7% vs. 1.8%, p = 1.0) between the modification and no modification groups. Similarly, among patients who underwent CTO modification, there were no significant differences in outcomes between early (< 60 days) and late (≥ 60 days) reattempts after the initial failure. Technical success was significantly higher after subintimal tracking and re-entry (STAR) than subintimal plaque modification (SPM) (82.5% vs. 60.0%, p = 0.028). Conclusions: CTO modification procedures were performed in approximately one of five CTO PCIs during the initial failed procedure. During reattempt CTO PCI, despite higher lesion complexity, CTO modification was associated with similar technical and procedural success and MACE compared to patients undergoing reattempt CTO PCI without prior CTO modification. Among modification techniques, STAR was associated with higher technical and procedural success than SPM
Analytical solutions and chaotic dynamics of the extended KP-Boussinesq model via phase diagnostics
No full textThis study investigates the dynamical behavior of a three-dimensional extended Kadomtsev-Petviashvili-Boussinesq (eKP-BO) equation, a higher-dimensional wave system that unifies Kadomtsev-Petviashvili-type weak dispersion with Boussinesq-type bidirectional propagation. Using the exp(-psi(xi ))-expansion method, we systematically construct diverse classes of exact solutions of hyperbolic, trigonometric, and rational types. These analytical results enrich the family of admissible solitary and lump-type wave structures and provide closed-form benchmarks for validating numerical simulations. Uncover the underlying dynamics by reducing the governing equation to a planar system. This can then be analyzed through phase portraits, bifurcation diagrams, Poincare sections, and time series. The results will reveal equilibrium structures such as centers, saddles, and cusps, as well as transitions from regular oscillations to period-doubling and fully developed chaos under period forcing. The study will also highlight both the advantages and limitations of the exponential expansion method, focusing on its ability to generate rich explicit solutions while noting its dependence on balance conditions. In sum, the results shed light on the nonlinear dispersive wave dynamics of the eKP-BO model in the unified framework and identify several potential future research paths, such as fractional-order models, stochastic perturbations, and hybrid analytical-numerical methods
Doğrusal Olmayan Sistem Durum Tahmini İçin Yapay Arı Kolonisi Algoritması Tabanlı Yeni Bir Parçacık Filtresi
No full textSıralı Monte Carlo yöntemi olarak da bilinen Parçacık Filtresinin (PF) temel fikri, durumun minimum varyans tahminini elde etmek için sistemin olasılık yoğunluk fonksiyonunu bazı ayrık rastgele örnekleme noktaları ile yaklaştırmaktır. Olası sistem durumlarını temsil etmek için bir dizi parçacıklar, ağırlıkları ve gözlemleri dâhil ederek tahmini sürekli olarak günceller. Bununla birlikte, çoğu parçacığın ağırlığı birkaç yinelemeden sonra ihmal edilebilir hale geldiğinden parçacık fakirleşmesi ve parçacık çeşitliliğinin azalması sorunları ortaya çıkar. Bu makale, doğrusal olmayan ve Gauss olmayan sistemler için durum tahmininde Parçacık Filtresi (PF) algoritmasının performansını artırmak için Yapay Arı Kolonisi (YAK) algoritmasının standart PF’ye dâhil edilmesini tanıtmaktadır. PF’nin sorunlarını çözmek için YAK algoritması, PF’nin yeniden örnekleme aşamasından sonra algoritmaya dâhil edilir ve parçacıkların istenen olasılık dağılımına daha etkin bir şekilde yaklaşmalarını sağlar. Önerilen yaklaşım, YAK algoritmasının güçlü yönlerinden yararlanarak en yüksek ağırlıklara sahip parçacıkları geliştirerek, sistemin gerçek durumunu daha iyi temsil etmeyi ve önemli parçacıkların sayısını artırmayı amaçlamaktadır. Önerilen yöntem, geleneksel PF ve Parçacık Sürü Optimizasyon (PSO) algoritmasıyla optimize edilmiş PF ile karşılaştırılmıştır. YAK tabanlı algoritmanın etkinliğini göstermek için bir bilgisayar simülasyonu gerçekleştirilmiştir. Simülasyon sonuçları, önerilen YAK tabanlı yeni algoritmanın tahmin doğruluğunu standart Parçacık Filtresine kıyasla önemli ölçüde iyileştirdiğini göstermektedir.The basic idea of the Particle Filter (PF), also known as the sequential Monte Carlo method, is to approximate the probability density function of the system with some discrete random sampling points to obtain a minimum variance estimate of the state. A set of particles to represent possible system states continuously updates the estimate by incorporating weights and observations. However, problems of sample impoverishment and reduced particle diversity arise as the weight of most particles becomes negligible after a few iterations. This paper introduces the incorporation of the Artificial Bee Colony (ABC) algorithm into the standard PF to improve the performance of the Particle Filter (PF) algorithm in state estimation for nonlinear and non-Gaussian systems. To solve the problems of the PF, the ABC algorithm is incorporated into the PF algorithm after the resampling stage, allowing the particles to more efficiently converge to the desired probability distribution. The proposed approach aims to better represent the true state of the system and increase the number of important particles by developing particles with the highest weights by utilising the strengths of the ABC algorithm. The proposed method is compared with conventional PF and PF optimised by Particle Swarm Optimisation (PSO) algorithm. A computer simulation is carried out to demonstrate the effectiveness of the ABC-based algorithm. The simulation results show that the proposed new ABC-based algorithm significantly improves the prediction accuracy compared to the standard Particle Filter