WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394
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Article Enhanced Mg–Zn–Ca Alloys Reinforced with Rare Earth Oxides for Biomedical Applications: Experimental Insights and ANFIS-Based Modeling(Springer, 2026) Mozafari, Farzin; Deka, Surja; Mallick, AshisTo enhance the corrosion resistance, biocompatibility, tribological, and mechanical properties of magnesium (Mg) alloys intended for biomedical implants, a new approach utilizing a microwave-sintered in situ hot extrusion-based powder metallurgy process was used to develop Mg-4Zn-0.5Ca/xCeO2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_2$$\end{document} (x = 0.5, 1, and 1.5 vol%) nanocomposites. The introduction of ceria nanoparticles (CONPs) has improved the compression characteristics of the nanocomposites in comparison with the monolithic Mg, and the ternary base alloy. The corrosion test results revealed that the alloy and nanocomposites promoted the formation of the magnesium hydroxide (Mg(OH)2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_2$$\end{document}) and hydroxyapatite (HA) layers on the sample surface. Among all samples, Mg-4Zn-0.5Ca /1.0CeO2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_2$$\end{document} demonstrated the lowest corrosion rate. In vitro cytocompatibility assessments were conducted through an extract assay method for different time periods, employing MG-63 cells. The developed alloy and nanocomposites demonstrated no harmful effects on MG-63 cells. An investigation into the dry sliding tribological characteristics of the alloy and nanocomposites at varied loads revealed several wear mechanisms, including abrasion, adhesion, delamination, oxidation, and plastic deformation. The addition of CONPs significantly enhanced the wear resistance of the nanocomposites. Our results provide a new venue to enhance the biocompatibility and in vitro degradation behavior of well-established Mg-Zn-Ca alloys, with a particular focus on the mechanical integrity of the developed samples for their clinical usage. An Adaptive Neuro-Fuzzy Inference system (ANFIS)-based modeling approach was also developed to individually characterize nanocomposite corrosion, cell viability, and wear behavior. The predictions offer compelling evidence of the reliability and accuracy of the proposed modeling strategy.Article Unveiling the Therapeutic Role of 3D-Cultured Mesenchymal Stem Cells in Diabetic Foot Ulcers through Transcriptomic Integration and Fibroblast Modulation(Springer, 2026-03-31) Ozturk, Esengul; Bicer, MesudeBackground Diabetic foot ulcers (DFUs) are among the most severe complications of diabetes mellitus and remain difficult to manage due to chronic inflammation, defective angiogenesis, delayed tissue repair, which increase the risk of recurrence and limb amputation. Standard treatments, such as debridement, infection management, pressure off-loading and revascularization, are commonly used, however; these interventions often inadequate to fully restore effective wound repair. Mesenchymal stem cells (MSCs) have attracted remarkable interest due to their potential regenerative ability and paracrine activity. Nevertheless, the molecular interaction between MSCs and fibroblasts under hyperglycemic conditions has not been fully elucidated. Objective This study aimed to examine differentially expressed genes (DEGs) associated with DFUs and MSC-related regenerative mechanisms using transcriptomic datasets (such as GSE143735, GSE199939, and GSE217709). Methods and results Differentially expressed genes and protein-protein interaction (PPI) network analysis were performed to determine central regulatory genes. Four key genes including CXCL1, MMP9, THBS1, and POSTN were recognized as hub genes related to inflammatory response, extracellular matrix reorganization, and angiogenesis. For experimental validation, L929 murine fibroblasts were exposed to high-glucose conditions to set-up an in vitro diabetic model and subsequently treated with MSCs with/without a 3D platform. Hyperglycemic conditions significantly reduced fibroblast proliferation and migration downregulated the expression of the identified hub genes and enhanced apoptotic activity. MSC treatment partially increased cellular function, while MSCs embedded into 3D culture enhanced a more pronounced recovery in both gene expression patterns and functional assays. Conclusions These findings suggest that high glucose impair fibroblast functions for wound repair, while 3D-cultured MSCs enhance regenerative responses and may represent a promising strategy for diabetic wound healing.Article Environmental Sustainability in Fragile States: The Role of Corruption Control, Political Stability, and Household Consumption in Somalia(Springer, 2026-03-28) Mohamed, Amir Mohamud; Warsame, Abdimalik Ali; Dirie, Khadar AhmedThe maintenance of environmental sustainability represents a worldwide pressing issue, especially for Somalia as an emerging nation that deals with environmental degradation because of unstable political leadership combined with corruption and financial limitations. This study analyzes the impact of corruption control, political stability, and household consumption on environmental degradation in Somalia. The study employs the kernel regularized machine learning method (KRLS) and a time-varying Granger causality approach. The KRLS addresses regression and classification tasks without depending on assumptions of linearity or additivity, whereas the time-varying Granger causality fixes instabilities caused by structural breaks, regime shifts, and provides a cause-effect relationships for specific years. The empirical results of the KRLS indicate that corruption control enhances environmental quality by reducing environmental degradation, whereas household consumption impedes it. Additionally, political stability has no discernible impact on environmental degradation. The time-varying Granger causality result revealed no significant causality from corruption control to environmental degradation in the forward and rolling windows. Two episodes of Granger causalities (2009-2011 and 2013-2016) are observed from corruption control to environmental degradation, and one episode of causality (2001-2004) from political stability to environmental degradation was detected in the recursive result. Finally, four episodes of causalities (2005-2007, 2008-2011, and 2014-2015) are observed from household consumption to environmental degradation in Somalia in the recursive result. This could be justified by the fact that climate consequences-droughts and floods-inhibit livelihood sources such as livestock and agriculture. Hence, people put pressure on forests in search of alternative income sources. Nevertheless, the study delivers practical recommendations to policymakers about using governance structures and economic decisions along with institutional mechanisms for creating sustainable environmental practices.Article Wireless Communication System Design for Point Machine Detection and Monitoring in Railways(Springer, 2026-03-09) Talu, Burak; Cetin, Fatih; Kilic, Veli Tayfun; Elden, Burakhan; Sanlier, Saban DuranThis paper reports on a wireless communication system that is used in railways to instantly detect and continuously monitor point machine positions. Also, with the system the position information is transmitted wirelessly to a train driver. The designed system is composed of TX and RX units. It has a compact structure and is fully modular. The TX unit of the system is placed near the railway point machines and the RX unit is located on a train. The designed system was constructed, and measurements were obtained on-site. Results show that the system point machine position data were accurately transmitted at 1350 m range which is much longer than the safe braking distance of a train. In addition, the measured 1 s data sampling time of the system allows the driver to continuously monitor current RPM positions as well as state changes. The maximum delay was found to be 3 s in the limit range of the communication. It is found that the system has a low power consumption and the designed system can work for long hours. The findings indicate that the designed wireless communication system has a high potential to be used in railways to prevent accidents and contribute to the overall safety and efficiency of operations.Article Effects of Gelatinization Process on Some Physicochemical Parameters, Pasting Characteristics and Some Nutritional Properties of Pulsed Based Flour Blends(Springer, 2026-02-17) Kahraman, Kevser; Yuksel, Ferhat; Karaman, SafaIn this study, a flour mixture was composed by three different flours (wheat flour (WF), cranberry bean flour (CBF) and lentil flour (LF)) depending on a constructed mixture design and some physicochemical parameters, pasting characteristics and some nutritional properties were investigated before and after gelatinization process. The highest total dietary fiber content was determined for the sole cranberry bean flour. After gelatinization of the samples, total dietary fiber levels of the samples increased significantly, and it ranged between 4.70 and 25.16% for uncooked samples and 8.46-29.09% for cooked samples. Resistant starch (RS) content of the samples was also affected by the gelatinization process. Wheat flour showed an increase in the RS content after gelatinization process and similar increment in the RS content was observed for the sole lentil flour. Peak viscosity was the highest for the wheat flour (2318 cP) and lowest for the lentil flour (716.5 cP). Glycemic index of the cooked samples changed significantly, and it ranged between 94.4 and 123.5. This study showed that making flour composite and gelatinization process had a significant effect on the pasting properties and nutritional characteristics of the pulse-based flour mixture.Article Deep-Learning Detection of Open-Apex Teeth on Panoramic Radiographs Using YOLO Models(Springer, 2025-12-23) Edik, Merve; Celebi, Fatma; Cukurluoglu, AykaganObjectivesThe use of deep learning in detecting teeth with open apices can prevent the need for additional radiographs for patients. The presented study aims to detect open-apex teeth using You Only Look Once (YOLO)-based deep learning models and compare these models.MethodsA total of 966 panoramic radiographs were included in the study. Open-apex teeth in panoramic radiographs were labeled. During the labeling process, they were divided into 6 classes in the maxilla and mandible, namely incisors, premolars, and molars. AI models YOLOv3, YOLOv4, and YOLOv5 were used. To evaluate the performance of the three detection models, both overall and separately for each class in the test dataset, precision, recall, average precision (mAP), and F1 score were calculated.ResultsYOLOv4 achieved the highest overall performance with a mean average precision (mAP) of 87.84% at IoU (Intersection over Union) 0.5 (mAP@0.5), followed by YOLOv5 with 85.6%, and YOLOv3 with 84.46%. Regarding recall, YOLOv4 also led with 90%, while both YOLOv3 and YOLOv5 reached 89%. Moreover, the F1 score was the highest for YOLOv4 (0.87), followed by YOLOv3 (0.86) and YOLOv5 (0.85).ConclusionsIn this study, YOLOv3, YOLOv4, and YOLOv5 were evaluated for the detection of open-apex teeth, and their mAP, recall, and F1 scores exceeded 84%. Deep learning-based systems can provide faster and more accurate results in the detection of open-apex teeth. This may help reduce the need for additional radiographs from patients and aid dentists by saving time.Article High-Accuracy Identification of Durian Leaf Diseases: A Convolutional Neural Network Approach Validated with K-Fold Cross-Validation and Bayesian Optimization(Springer, 2025-11-18) Soylemez, Ismet; Nalici, Mehmet Eren; Unlu, RamazanTo address the economic losses caused by plant diseases in durian farming, this study presents an optimized deep learning model that diagnoses diseases from leaf images with high accuracy. The model's performance is maximized through Bayesian optimization and hyperparameter tuning, while its reliability is maximized through layered five-fold cross-validation. Training the convolutional neural network model on 2595 leaf images displaying six different states (five diseased and one healthy) resulted in an average test accuracy of 91.98%. This high, consistent success rate demonstrates the model's generalizability to different datasets without overfitting. While the 'Healthy' and 'Algal' classes were successfully detected with high F1-scores, there are difficulties distinguishing between the 'Blight' and 'Colletotrichum' classes due to visual similarities. This study establishes a new reference point for durian disease classification and makes a significant contribution to the development of reliable artificial intelligence-based diagnostic tools for precision agriculture.Article Citation - WoS: 1Citation - Scopus: 2Green Synthesis and Characterization of Zinc Oxide Nanoparticles via Thyme for Biomedical Applications: Effect of Plant Extract Concentration and Drying Method(Springer, 2025-10-15) Karakaya, Humeyra; Kizilates, Burcu; Erdem, IlkerGreen synthesis of nano particles using plant extracts is sustainable, cost-effective, and eco-friendly. However, the synthesis parameters are still being investigated. In this study, zinc oxide nanoparticles (ZnO NPs) were prepared via thyme extract (green synthesis) and the effect of synthesis parameters were investigated. Samples with different concentrations of thyme plant extract (PE) (10, 16 & 24% (v/v) PE / Zn salt solution) were prepared and two different drying methods (freeze-drying (FD) and oven-drying (OD)) were performed. XRD results showed the hexagonal crystalline ZnO were formed with considerable crystallinity (70.8-75.1%) without further heat treatment (calcination). The crystallite sizes of ZnO NPs were determined to be in the range of 11.9-14.8 nm. The ZnO NPs prepared via PE concentration of 16% (v/v) and freeze-drying was with the finest crystallite size (11.9 nm) and considerable crystallinity (72.9%). ZnO NPs prepared via FD method were found to have smaller particle sizes, thus providing a higher surface-to-volume ratio. DLS (dynamic light scattering) analysis was used for determining the particle size distribution (PSD) and surface charge of ZnO NPs at acidic, neutral and basic pH values. The antibacterial characteristics of ZnO NPs were determined against Gram (+) and (-) bacteria. The ZnO NPs with the finest microstructure (16% PE (v/v), FD) had the highest antibacterial activity. The green synthesized ZnO NPs prepared in this study may be promising candidates for various applications including biomaterials and biomedical applications with their fine microstructure and considerable antibacterial activity.Article Enhanced Photoluminescence via Plasmonic Gold Nanoparticles and Improved Stability of Perovskite Nanocrystals in Macroporous (Polydimethylsiloxane) PDMS Matrices(Springer, 2025-10-09) Ocal, Sema Karabel; Tiras, Kevser Sahin; Onses, M. Serdar; Mutlugun, EvrenIn this work, we report a simple and cost-effective method for improving both the environmental stability and photoluminescence quantum efficiency (PLQY) of perovskite nanocrystals (PNCs). Through their embedding in a specially designed macroporous polydimethylsiloxane (MPDMS) matrix and incorporation of plasmonic gold nanoparticles (Au NPs), remarkable improvements are achieved. The resulting MPDMS@PNC composites are seen to retain near-unity quantum efficiency even after 24-h immersion in water and are observed to retain over 85% of the original efficiency even at 75 degrees C, displaying excellent thermal stability. More interestingly, by incorporating Au NPs and subjecting the material to mechanical pressure, the lifetime of the PNCs gets further increased. This is due to the more intimate spatial arrangement of Au NPs in the porous matrix, enhancing localized surface plasmon resonance (LSPR) coupling and thereby enhancing the photoluminescence (PL) of the PNCs. In general, this approach offers a scalable and robust route to designing stable, high-performance perovskite-based materials for next-generation optoelectronic applications.Article Citation - WoS: 2Citation - Scopus: 2Pangenome Analysis and Genome-Guided Probiotic Evaluation of Cyclic Dipeptides Producing Levilactobacillus Brevis DY55bre Strain From a Lactic Acid Fermented Shalgam to Assess Its Metabolic, Probiotic Potentials, and Cytotoxic Effects on Colorectal Cancer Cells(Springer, 2025-10-01) Yetiman, Ahmet E.; Horzum, Mehmet; Kanbur, Ertan; Cadir, Mehmet; Bahar, Dilek; Gurbuz, Serife; Akbulut, MikailThis study investigates the genetic, metabolic, and probiotic characteristics of Levilactobacillus brevis DY55bre, a strain isolated from the traditional Turkish fermented beverage, shalgam. Whole-genome sequencing revealed a circular genome of 2.485 Mb with a GC content of 45.72%, predicted 2791 genes, and multiple CRISPR-Cas systems. Pangenome analysis demonstrated an open structure, with 18.9% core genes and 103 strain-specific genes, highlighting its genetic diversity. The DY55bre exhibits heterofermentative carbohydrate metabolism due to the presence of the araBAD operon and the lack of 1-phosphofructokinase (pfK) and fructose-1,6-bisphosphate aldolase enzymes. Probiotic evaluation revealed firm survival under simulated gastrointestinal conditions, including resistance to acidic pH (as low as 3.0) and bile salts (up to 1%), along with significant adhesion to intestinal epithelial cell lines (HT29;59.3%, Caco-2;87%, and DLD-1;60.8%). The strain exhibited high auto-aggregation (84.55%) and cell surface hydrophobicity (56.69%), essential for gut colonization. Safety assessments confirmed its non-hemolytic nature and absence of horizontally acquired antibiotic resistance genes. Notably, GC-MS analysis identified bioactive cyclic dipeptides, Cyclo(D-Phe-L-Pro) and Cyclo(L-Leu-L-Pro), which demonstrated cytotoxic effects against colorectal cancer cell lines, with IC50 values of 7.71 mg/mL for HT29 and 3.19 mg/mL for DLD-1. The cell-free supernatant exhibited antimicrobial activity against pathogens, likely due to the synergistic effects of cyclic dipeptides, organic acids, and other metabolites. Antioxidant assays revealed significant ABTS+ (76.63%) and DPPH (34.25%) radical scavenging activities, while cholesterol assimilation tests showed a 27.29% reduction. These findings position the DY55bre as a promising candidate for functional foods, nutraceuticals, and therapeutic applications, warranting further in vivo validation.