Istanbul Technical University
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Particle-Scale Energy Dynamics and Gas Desorption Behavior of Coal Particulates Under Triaxial Stress Conditions for Outburst Risk Prediction
No full texthttps://doi.org/10.2139/ssrn.529688
Grounded Answer Generation over Multimodal Financial Records via Semantic Indexing
No full texthttps://doi.org/10.1109/ubmk67458.2025.1120695
Antiseptic Soaking of Tendon Xenografts: A Biomechanical Study on Structural Integrity as a Model for ACL Autografts
No full textAbstractDuring anterior cruciate ligament (ACL) reconstruction, intraoperative graft contamination or postoperative infection remains a notable clinical concern. While antiseptic solutions are increasingly employed for graft decontamination and infection prophylaxis, the potential impact of these agents on the biomechanical integrity of tendon grafts has not been fully elucidated. This experimental study aimed to evaluate the biomechanical effects of soaking tendon grafts in vancomycin, chlorhexidine, and povidone-iodine solutions. Fresh bovine deep digital flexor tendons were used to simulate ACL autografts and randomly assigned to four groups (n = 6): 4% chlorhexidine, 10% povidone-iodine, 5 mg/mL vancomycin, and 0.9% isotonic saline (control). After 30-minute soaking, tendons were sutured using a four-rip-stop technique and biomechanically tested using a servohydraulic tensile system. Failure load, stiffness, and cyclic elongation were measured. Statistical analysis was performed using Kruskal–Wallis and Mann–Whitney U tests with Bonferroni correction. Vancomycin and chlorhexidine groups exhibited significantly lower cyclic elongation compared to control and povidone-iodine groups. Failure load was also significantly higher in these groups, particularly compared to povidone-iodine, which demonstrated the weakest biomechanical performance. No significant differences in stiffness were observed across groups. Vancomycin and chlorhexidine can be safely used for short-term antiseptic soaking without compromising graft mechanical integrity. In contrast, povidone-iodine may weaken tendon structure. These findings may guide antiseptic use during ACL reconstruction and in managing contaminated tendons in open injuries.https://doi.org/10.1055/a-2716-457
Assessing Urban Identity: An Applied Approach to the Case of Ataşehir
No full textThis study explores urban identity through theoretical and practical dimensions to preserve and enhance the unique characteristics of cities. Rapid urbanization, unplanned development, and homogenization threaten urban identity and undermine the sense of belonging. The research examines the elements that influence urban identity and assesses existing literature on identity loss and its implications for urban planning. By integrating theoretical discourse with an applied case study in Ataşehir, this study aims to provide a practical tool for urban planning processes. The research methodology builds on Mansour, Alves, and Costa’s comprehensive approach to assessing urban identity, tested in a real-world urban context. Findings will provide concrete insights into the strengths and weaknesses of the methodology while guiding planners in preserving urban identity. The study enhances the literature by bridging theoretical and practical perspectives, emphasizing urban identity as a dynamic and evolving concept.https://doi.org/10.38027/iccaua2025tr0037https://doaj.org/article/9183475e0f8b494ca4e9c5369d13960
Interpretable and Robust Ensemble Deep Learning Framework for Tea Leaf Disease Classification
No full textTea leaf diseases are among the most critical factors affecting the yield and quality of tea harvests. Due to climate change and widespread pesticide use in tea cultivation, these diseases have become more prevalent. As the demand for high-quality tea continues to rise, tea has assumed an increasingly prominent role in the global economy, thereby rendering the continuous monitoring of leaf diseases essential for maintaining crop quality and ensuring sustainable production. In this context, developing innovative and sustainable agricultural policies is vital. Integrating artificial intelligence (AI)-based techniques with sustainable agricultural practices presents promising solutions. Ensuring that the outputs of these techniques are interpretable would also provide significant value for decision-makers, enhancing their applicability in sustainable agricultural practices. In this study, advanced deep learning architectures such as ResNet50, MobileNet, EfficientNetB0, and DenseNet121 were utilized to classify tea leaf diseases. Since low-resolution images and complex backgrounds caused significant challenges, an ensemble learning approach was proposed to combine the strengths of these models. The generalization performance of the ensemble model was comprehensively evaluated through statistical cross-validation. Additionally, Grad-CAM visualizations demonstrated a clear correspondence between diseased regions and disease types on the tea leaves. Thus, the models could detect diseases under varying conditions, highlighting their robustness. The ensemble model achieved high predictive performance, with precision, recall, and F1-score values of 95%, 94%, and 94% across folds. The overall classification accuracy reached 96%, with a maximum standard deviation of 2% across all dataset folds. Additionally, Grad-CAM visualizations demonstrated a clear correspondence between diseased regions and specific disease types on tea leaves, confirming the ability of models to detect diseases under varying conditions accurately and highlighting their robustness.https://doi.org/10.3390/horticulturae11040437https://doaj.org/article/33dfdf6389d64a478b187af06420d85
Integrate Occlusion Control Block to Your Tracker
No full texthttps://doi.org/10.1007/978-3-031-99965-9_1
Novel Game-Theoretical Approach in Blockchain-Aided Communication at Internet of Drones
No full texthttps://doi.org/10.1109/mce.2025.353010
Harnessing lignin in membrane engineering: from green polymer to high-performance applications
No full texthttps://doi.org/10.1016/j.ijbiomac.2025.14812
Rheological and Multifunctional Properties of PBAT / CNT Nanocomposites With Diverse CNT Dispersion Quality Tuned by the Processing Parameters
No full textABSTRACT This study investigates the effect of processing parameters on the dispersion quality of carbon nanotube (CNT) within poly(butylene adipate‐co‐terephthalate) (PBAT) matrix and the corresponding rheological behavior, electrical conductivity, dielectric properties, and electromagnetic interference shielding effectiveness (EMI‐SE). Neat PBAT and nanocomposites containing 1, 3, and 5 wt% CNT were prepared using an internal melt mixer with varying processing temperatures and screw speeds. Small amplitude oscillatory shear rheological analysis revealed that an increase in processing temperature resulted in a more significant increase in complex viscosity and storage modulus at low frequencies reflecting a better CNT dispersion and the formation of a stronger network. Higher mixing speeds also facilitated CNT dispersion more effectively; although further increases could cause the mechanical degradation of PBAT molecules and CNTs breakage. Scanning electron microscopy analysis confirmed the better and more uniform CNT dispersion when the nanocomposites were processed at higher temperatures and mixing speeds. The changes in electrical conductivity, dielectric permittivity, and EMI‐SE of the nanocomposites were consistent with the melt rheological results confirming a symbiotic correlation between these characteristics. Nanocomposites with 5 wt% CNT revealed DC conductivity and EMI‐SE values of about 10 −7 S/cm and 35–38 dB, respectively, when processed at 150°C and 100 rpm. These values, however, reached about 10 −3 S/cm and 44–50 dB, respectively, when nanocomposites were prepared at 190°C and 200 rpm. Under this preparation condition, the onset of rheological and electrical conductivity percolation thresholds was estimated at CNT contents of about 0.18 and 0.45 wt%, respectively. A higher processing temperature (190°C) and increased mixing speed (200 rpm) were found to be critical in achieving uniform CNT dispersion and enhancing the multifunctional properties of the nanocomposites.https://doi.org/10.1002/pc.7060
Reactivity of Joncryl chain extender in PLA/PBAT blends: Effects of processing temperature and PBAT aging on blend performance
No full textThis study investigates the effects of incorporating an epoxy-based Joncryl chain extender on the reactivity and performance of amorphous polylactide/poly(butylene-adipate-co-terephthalate)(PLA/PBAT) blends processed at various temperatures. The impact of using freshly provided PBAT versus aged PBAT on Joncryl's reactivity and blend performance is also examined. Joncryl's interactions with PLA, PBAT, and their blends at different temperatures were assessed using rheological analysis. The blends morphology, tensile and impact properties, and dynamic mechanical analysis were examined. Increasing the processing temperature enhances Joncryl's reactivity with PLA more noticeably than that with PBAT but also accelerates PLA degradation. Although PBAT exhibits reactivity with Joncryl, aged PBAT with significantly suppressed melt rheological properties remained largely unaffected by the presence of Joncryl. Overall, the melt rheological properties of blends improved with Joncryl addition at higher processing temperatures, likely due to the increased Joncryl reactivity and enhanced compatibilization. The tensile properties of blends processed at higher temperatures are more adversely affected by bioplastic degradation, although Joncryl addition mitigates these effects. Impact strength increased with higher processing temperatures due to enhanced Joncryl reactivity, more effective interfacial compatibilization, and PBAT phase droplet refinement. Blends prepared with aged PBAT exhibited markedly poorer mechanical performance, attributed to severely suppressed melt properties and resultant non-homogeneous blend morphology.https://doi.org/10.1016/j.ijbiomac.2025.140703https://pubmed.ncbi.nlm.nih.gov/39914529https://avesis.yildiz.edu.tr/publication/details/8d9b8b35-58c1-4b85-b4c4-ba8acbe48662/oa