WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.14720/3

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Mixed Hydrogenetic-Hydrothermal Genesis of Quaternary Ferromanganese Nodules in a Tectonically Active Lacustrine Basin, Eastern Türkiye
(Pergamon-Elsevier Science Ltd, 2025) Uner, Tijen
This study presents a detailed investigation of the mineralogical, geochemical, and rare earth element (REE) characteristics of ferromanganese nodules found within Quaternary lacustrine sediments in the Agri region of Eastern Anatolia, T & uuml;rkiye. These nodules, primarily composed of goethite and manganite with minor quartz, exhibit botryoidal and colloform textures typical of low-temperature diagenetic environments. Raman and XRD analyses identified significant iron and manganese mineral phases, while SEM-EDX revealed trace amounts of Co, Ni, and Zn associated with these phases. Chondrite-normalized REE patterns demonstrate light REE enrichment, a weak negative europium anomaly (EuN/Eu* = 0.69-0.84), and variable cerium anomalies (CeN/Ce* ranging from 0.74 to 1.95, corresponding to both weak negative and positive Ce anomalies), indicating a mixed hydrogenous and hydrothermal origin under fluctuating redox conditions. These geochemical signatures, together with sedimentological evidence, suggest formation within a restricted lacustrine environment characterized by episodic anoxia and limited detrital input. The results contribute to a broader understanding of Fe-Mn mineralization in continental settings and underscore the influence of volcanic and tectonic processes on nodule genesis.
Why Disadvantaged Primary School Students in Rural Areas Have Lower Reading Skills? A Critical Assessment
(Routledge Journals, Taylor & Francis Ltd, 2025) Kiziltas, Yusuf; Kultas, Emrah
Inequalities between T & uuml;rkiye's geographical regions are significant. It is an important fact that students continuing their education in rural areas in eastern T & uuml;rkiye face many challenges compared to their peers in urban centers. The geography of rural areas can hurt students in several ways, particularly in terms of reading skills. The low reading skills of students in rural areas have been a serious problem in eastern T & uuml;rkiye for many years. National and international exam results also show that reading skills are lower in rural areas. In this study, the reasons for the low reading skills of primary school students in rural areas were critically examined through a literature review. The discussions include approaches such as the Matthew effect, spatial justice theory, and faucet theory. According to critical evaluations, the reasons for the low reading skills of disadvantaged primary school students in rural areas in eastern T & uuml;rkiye are pretty diverse. The socioeconomic levels of families, inequalities in opportunities and resources, school closures, negative factors related to location and geography, linguistic differences, problems with teaching materials, temporary teaching arrangements, and low levels of parental involvement are at the forefront.
Synthesis and Characterisation of Pd/MIL68(Al) Nanoparticles for High Performance Catalytic Reduction of 4-Nitrophenol
(Springer, 2025) Ruzgar, Adem
The discharge of 4-nitrophenol, one of the most significant, widespread, and hazardous organic pollutants found in industrial wastewater, into clean water resources without undergoing adequate and necessary treatment/conversion processes has become a multidimensional issue that threatens all aquatic life. In this study, the reduction of 4-nitrophenol to 4-aminophenol using an efficient, environmentally friendly, and sustainable method was targeted. For this purpose, Pd/MIL68(Al) catalyst was prepared with 2% metal loading using a simple and conventional wet impregnation method. MIL68(Al), an MOF recently attracting attention due to its superior properties, was synthesised using an efficient and environmentally friendly method as support material in the first step of nanocatalyst synthesis. The prepared Pd/MIL68(Al) catalyst was tested in the reaction of the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4 by considering different parameters. In the study where the structure and surface morphology of the Pd/MIL68(Al) catalyst were elucidated using characterisation techniques such as ICP-OES, XRD, SEM, SEM/EDX, TEM, FTIR and XPS, it was determined that Pd(0) nanoparticles were well dispersed on the MIL68(Al) support, with an average particle size of 3.25 +/- 0.22 nm. As a result of the interpretation of the data obtained from the study, the TOFinitial value for 4-NP was determined as 43.42 min-1. In the studies carried out to determine the reusability rate of Pd/MIL68(Al) nanocatalyst, it was determined that Pd/MIL68(Al) nanocatalyst exhibited excellent catalytic efficiency and stability (92%) even after five catalytic cycles. Both the simple preparation process, catalytic efficiency, and high reusability rate of the Pd/MIL68(Al) nanocatalyst are the grounds for the evaluation of Pd/MIL68(Al) nanocatalyst as an important alternative for the reduction of 4-nitrophenol and wastewater treatment.
Dose Enhancement Effects of Different-Sized Nanoparticles on Tumors and Surrounding Tissues Using Geant4 Track Structure Simulation
(Sciendo, 2025) Tugrul, Taylan
Free radicals, which are the most important contributors to cell death in radiotherapy, appear to increase in the presence of nanoparticles. The nanoparticles can be localized within tumor tissues, providing enhanced protection to normal tissues during radiation therapy while achieving significant dose enhancement within tumors. In our study, the dose effects of different sizes of spherical gold nanoparticles were analyzed in the tumor environment and surrounding tissues under photon radiation at various energies with the track structure code using the TOPAS interface. The nano-lattice method was used to create an environment similar to the diffusion-based distribution of nanoparticles in the medium. The Geant4-DNA code was utilized for simulations conducted in this study. Although the interaction cross-section is lower at MeV photon energy levels, the results still indicate an increase in dose due to the presence of nanoparticles (NPs) in the medium. As the size of gold nanoparticles increases, the spread in dose enhancements becomes more apparent. The lowest average dose enhancement factor (DEF) values at lateral points were observed for 28.4 nm NPs at MeV photon energy. In this study, the contribution of gold nanoparticles to dose enhancement was investigated using the Monte Carlo track structure algorithm. Additionally, the potential dose variations in the surrounding tissue resulting from the introduction of gold nanoparticles were analyzed. Even though an increase in DEF values was observed at MeV energy levels, these values might vary with a better understanding of biological effects such as cell cycle disruption, oxidative stress, and impaired DNA repair. This study offers valuable insights into nanoparticle-assisted radiation applications, including optimal nanoparticle size and applicable energy levels. By enhancing our understanding of the effects on tissues beyond the tumor and within the surrounding environment, it aims to provide critical information for researchers in the field and make a meaningful contribution to the literature.
Multimodal Prediction of Pathological Complete Response in Esophageal Cancer Using Automated Machine Learning and Variational Autoencoder-Based Synthetic Data Augmentation
(Amer Assoc Cancer Research, 2025) Dincer, Sefika; Tugrul, Taylan; Kara, Mahmut; Aldemir, Mehmet Naci
Therapeutic Potential of CAPE in Targeting Hallmarks of Cancer in TPC-1 Thyroid Cancer Cells Through Modulation of Mitochondrial Membrane Potential
(Wiley, 2025) Tuluce, Yasin; Bucak, Humeyra; Kostekci, Sedat
The objective of this study was to examine the chemotherapeutic effect of CAPE, via the mitochondrial membrane potential (MMP, Delta psi m) pathway in TPC-1 human papillary thyroid cancer cells. The cytotoxic effect of CAPE was evaluated using MTT and crystal violet assays, while its apoptotic activity was measured using Bax, Bcl-2, Caspase-3,-8,-9 and Apaf-1 assays. Effects on mitochondria were performed by analyzing JC-1 fluorescent probe-MMP, ROMO1 and mitochondrial ATP-synthase. The analysis of ROS and 8-OHdG was undertaken to assess the degree of oxidative stress and DNA damage, while LDH analysis was used as a marker of both cytotoxicity and cellular membrane damage. To determine antimetastatic activity, cell migration and colony formation assays were performed. Finally, Giemsa staining was chosen for cytomorphological analysis. CAPE treatment in TPC-1 cells was selected as the effective dose (IC50: 25 mu M/48 h) for further experiments, and it was found that this reduced Bcl-2 levels and increased the activation of key components Bax, Caspase-3,-8,-9 and Apaf-1, indicating that CAPE-induced cell death was apoptosis-dependent. The study revealed that CAPE induced mitochondrial depolarization, leading to a substantial decrease in mitochondrial ATP-synthase, along with a notable increase in intracellular ROS, ROMO1 levels, and 8-OHdG DNA damage and extracellular LDH. Furthermore, CAPE exhibited a significant inhibitory effect on cell migration and colony formation, accompanied by cytomorphological changes. In conclusion, this study demonstrates that CAPE, which shows bioactivity by modulating MMP, can target several hallmarks of cancer in TPC-1 cells and therefore has an important potential for future in vivo research.
Hydrothermal Liquefaction of Sinapis Arvensis Biomass Using TiO2-Supported Metal Catalysts: A Study on Bio-Oil Yield and Composition
(Elsevier, 2026) Durak, Halil; Genel, Salih; Genel, Yasar
The development of catalytic systems for hydrothermal liquefaction (HTL) is crucial for transforming lignocellulosic biomass into biofuels with high energy density. This research investigates the HTL process of Sinapis arvensis biomass using TiO2-supported catalysts, specifically Fe, Al, and Fe-Al, at temperatures from 275-325 degrees C. The catalysts were synthesized through incipient wetness impregnation and characterized using techniques like X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray fluorescence (XRF), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), and inductively coupled plasma optical emission spectrometry (ICP-OES) to evaluate element distribution and surface chemistry. Findings show that the Al/TiO2 catalyst boosted lighter bio-oil production via acid-catalyzed dehydration and decarboxylation, while the Fe/TiO2 catalyst favored heavier oils through redox-assisted depolymerization. The Fe-Al/TiO2 bifunctional catalyst exhibited superior biomass conversion, yielding more aliphatic hydrocarbons. Gas chromatography-mass spectrometry (GC-MS) revealed how catalysts influenced product distributions, increasing monoaromatic and aliphatic compounds and reducing oxygenated entities. Elemental analysis confirmed higher carbon content, lower oxygen levels, and improved higher heating values (HHVs) in catalyzed bio-oils, indicating enhanced fuel quality.
Effect of Geometry and Fiber Type on Energy Absorption in Polymer Based Composite Crash Boxes: An Experimental Study
(Wiley, 2025) Kosedag, Ertan; Araz, Zumray; Erkek, Baran
Vehicle crash boxes, mounted on the chassis before the bumper, absorb impact energy to protect passengers, but their metal construction adds weight, prompting increased research into lightweight composite alternatives with comparable strength. In this study, energy absorption values (EA), specific energy absorption (SEA), peak forces (PF) and crashing force efficiency (CFE) of carbon fiber, glass fiber, and aramid fiber reinforced composite crash boxes with epoxy resin matrix were compared. Composite crash boxes with different geometries were fabricated using vacuum infusion method in three different geometries: hexagonal, circle, and square. Unlike hand lay-up and prepreg winding methods, vacuum infusion method was chosen because it provides homogeneous distribution of epoxy resin. The crashworthiness of the samples was evaluated through quasi-static compression tests. The best energy absorption performance was obtained with the hexagonal carbon fiber-reinforced composite crash box (246.17 J), corresponding to a specific energy absorption of 8.57 J/g. Although aramid fiber-reinforced specimens showed lower energy absorption, they exhibited the highest crash force efficiency among all tested configurations. These results confirm the significant influence of both fiber type and geometry on the crashworthiness of polymer-based composite crash boxes. The study highlights that hexagonal geometry consistently provided superior energy absorption across all fiber types, while carbon fiber-reinforced composites demonstrated the best overall mechanical performance, making them strong candidates for lightweight crashworthiness applications.
Explainable Machine Learning-Based Prediction of CO2 Emissions From Passenger Vessels
(Pergamon-Elsevier Science Ltd, 2025) Sahin, Volkan
Accurate prediction of CO2 emissions from maritime transportation is critically important for environmental sustainability and effective regulatory action. In this study, hourly CO2 emissions were estimated using Random Forest and Extreme Gradient Boosting algorithms, trained on structural and operational data from approximately 2000 passenger ships-including Gross Tonnage, Speed, Length, Beam, Net Tonnage, Draft, and Deadweight Tonnage. Both models demonstrated high predictive accuracy (R2 = 0.92), with Extreme Gradient Boosting achieving lower Root Mean Square Error and Mean Absolute Error values. To enhance transparency, SHapley Additive Explanations analysis was applied, identifying Gross Tonnage, Speed, and Length as the most influential features. A simplified model using only these three variables achieved comparable performance to the full model, offering a more efficient alternative. Furthermore, the ability to predict emissions using only structural ship data provides a practical and cost-effective solution for shipowners and regulators to comply with the European Union's Monitoring, Reporting and Verification System and the International Maritime Organization's Data Collection System. It also supports strategic planning for carbon pricing schemes and Emission Control Areas, where stricter environmental regulations apply. These findings enhance the practical and policy relevance of explainable artificial intelligence-based emission models in the maritime sector.
Interaction Activity of Metal-Free Phthalocyanine Compound Bearing Tetra -(2 Accent>-Cyanoethyl)aminoethylsulfanyl) Units With DNA
(Chem Soc Pakistan, 2025) Arslantas, Ali; Agirtas, Mehmet Salih
The phthalocyanine having 4-(2-(N-2-cyanoethyl)aminoethylsulfanyl) group had been reported earlier in the literature. In this current studying, DNA binding activity of 1Pc phthalocyanine bearing 4-(2-(N-2-cyanoethyl)aminoethylsulfanyl units was examined spectroscopically via elctronic absoption, A fluorescence titration, melting point profile, A electrophoresis and viscosity methods. The interaction activity of 1Pc compound was examined at differing concentrations. UV/Vis spectrometer, viscosity, Afluorescence spectroscopy and thermal melting temperature confirmed that 1Pc binds to the DNA. The K-b of 1PcAis also estimated via UV/Vis titration and K-b of 1Pc was computed as 2.1394 x 10(6) M-1. The K(b)value demonstrated that 1Pc reacts with DNA by an intercalative mechanism. Alongside this research, the mechanism by which the compound binds to DNA was investigated by determining Tm. The Tm of DNA + 1Pc complex was identified as 74.31. This data confirmed that 1Pc binds to DNA intercalatively. All the results obtained from the used methods demonstrated that 1Pc phthalocyanine compound has an efficient DNA interaction activity and 1Pc phthalocyanine compound interacts with DNA via an intercalative mechanism. As a result, the compound mayAbe a therapeutic agent due to its DNA interaction property.
Radiotherapy of Primary and Recurrent Cervical Cancer
(BMJ Publishing Group, 2021) Karaman, Erbil; Bartnik, Pawel
Radiotherapy in Management of Primary and Recurrent Cervical Cancer
(BMJ Publishing Group, 2023) Kacperczyk-Bartnik, Joanna; Karaman, Erbil
Changes in Some Seedling Growth Parameters, Nutrient Content and Enzyme Activity in Different Melon (Cucumis Melo L.) Genotypes Under Deficit Irrigation Conditions
(Tarbiat Modares Univ, 2025) Cakmakci, Ozlem; Bitik, Selma Kipcak; Ekincialp, Aytekin; Erdinc, Ceknas; Kabay, Turgay; Eser, Fuat; Sensoy, Suat
Increasing need for drought adaptation measures to conserve water and sustain crop yield in water-scarce regions is driven by severe and recurrent droughts. Achieving sustainable production entails studying deficit irrigation as a means to enhance water productivity and selecting genotypes resilient to soil water deficits. In the present study, 17 different melon (Cucumis melo L.) genotypes collected from the Van Lake Basin and 3 hybrids and 1 standard melon cultivar for control purposes were used for this purpose. The study was carried out under climate room conditions. Two different irrigation levels (I100: 100% full irrigation, I50: 50% Deficit Irrigation-DI) were applied in the study for deficit irrigation. Water applications started with the emergence of the second true leaf of the plants and, after one-month, different growth, nutrient, and enzyme contents of the seedlings were determined. In general, it was determined that deficit water application negatively affected seedling growth, and root dry matter, stomatal opening and density, potassium, APX and SOD enzymes, and MDA content increased, while the other tested parameters decreased. The melon genotypes of the Van Lake Basin were found to vary in response to deficit irrigation treatments.
Evaluating the Effectiveness of No Evidence of Disease Activity-3 in Managing Progression Independent of Relapse Activity and Relapse-Associated Worsening in Multiple Sclerosis
(Sage Publications Ltd, 2025) Ozakbas, S.; Ozcelik, S.; Ozdogar, A.; Alizada, S.
Enhancing Disability Progression Assessment in Multiple Sclerosis
(Sage Publications Ltd, 2025) Ozakbas, S.; Ozcelik, S.; Ozdogar, A.; Alizada, S.
Construction of Magnetically Recoverable Palladium Deposited Polymer Brush Catalyst for Reduction of Organic Pollutants
(Pergamon-Elsevier Science Ltd, 2026) Yavuz, Cenap; Karakoyun, Necdet
Water contamination by nitroaromatic compounds and synthetic dyes poses serious environmental and health hazards, requiring the development of efficient, recyclable, and eco-friendly catalytic systems. In this study, a magnetically recyclable Pd-PAAm@Fe3O4 nanocatalyst was synthesized via surface grafting and reduction techniques, ensuring uniform dispersion of Pd0 nanoparticles on polyacrylamide-modified Fe3O4 without toxic reducing agents. The catalyst exhibited excellent activity for reducing 2-NP, 4-NP, 2,4-dinitrophenol, 2-NA, 4NA, and 2,4-dinitroaniline, following pseudo-first-order kinetics, with the highest kapp value of 5.23 min-1. It also showed rapid degradation of organic dyes, achieving complete decolorization of methyl orange in 45 s and methylene blue in 120 s. The catalyst retained over 99 % efficiency for 4-NP reduction over five cycles, with low Pd leaching (0.10-0.16 %) and stable structure confirmed by XRD, SEM, TEM, and XPS, highlighting its potential for sustainable environmental remediation.
Artificial Intelligence, Social Influence, and AI Anxiety: Analyzing the Intentions of Science Doctoral Students to Use ChatGPT With PLS-SEM
(Springernature, 2025) Uludag, Fatih; Kilic, Eylem; Celik, H. Eray
The widespread use of AI-based applications, such as ChatGPT, in higher education has raised questions about how doctoral students adopt these technologies, particularly in science departments. However, traditional models, such as the Technology Acceptance Model (TAM), may fall short in fully capturing users' behavioral intentions toward emerging technologies. This study aims to investigate PhD students' behavioral intention to use ChatGPT for learning purposes by proposing an extended version of the TAM. The proposed model incorporates five additional factors: Social Influence (SI), Perceived Enjoyment (PEN), AI Self-Efficacy (AI-SE), AI's Sociotechnical Blindness (AI-STB), and Perceived Ethics (AI-PET). Data were collected from 361 PhD students across 35 universities and analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM). The results reveal that all proposed factors significantly influence students' behavioral intention to use ChatGPT. This study contributes to the literature by introducing new external variables into the TAM framework and providing empirical insights into doctoral students' acceptance of AI tools in science education, thereby offering a novel perspective for future research and educational practice.
A Comparative Analysis of Land Use Classification Methods Using Landsat and Ancillary Data in Urban Mapping
(Springer Heidelberg, 2025) Ozvan, Hande; Satir, Onur
This study compares the performance of parametric (LDA) and non-parametric (CTA, RF, SVM) classification algorithms in mapping urban and surrounding land cover types in Balikesir, T & uuml;rkiye, using Landsat 8 OLI/TIRS imagery and ancillary data. Seven land cover classes-built-up areas, roads, water bodies, forests, meadows, agriculture, and barren land-were classified based on 2,480 ground truth points. The Random Forest (RF) classifier achieved the highest overall classification accuracy (Kappa = 0.90) and an F1-score of 0.99 for the built-up class, outperforming LDA (Kappa = 0.86), SVM (0.83), and CTA (0.78). The integration of the Digital Elevation Model (DEM) with spectral wavebands improved classification performance, particularly in distinguishing urban areas from spectrally similar classes such as barren land and roads. In contrast, additional indices like NDBI and SAVI provided only marginal improvements. Results suggest that incorporating DEM enhances model robustness and spatial accuracy, while the sole use of ancillary indices may introduce redundancy. The study underscores the importance of selecting appropriate classifier-data combinations and highlights the utility of the F1-score, alongside Kappa, for evaluating class-specific accuracy. This research contributes to urban land cover mapping by offering a comparative framework that integrates ancillary variables, helping to refine classification strategies in heterogeneous landscapes.
Modeling and Analyzing Cybersecurity Risk Propagation in Ports Using Fuzzy Cognitive Maps: System Sensitivity to Key Threat Factors
(Elsevier Sci Ltd, 2025) Soner, Omer
The growing digital complexity of modern port ecosystems has introduced a multidimensional cybersecurity challenge-one that transcends isolated technical vulnerabilities and emerges from the interplay between infrastructure, human behavior, and institutional governance. This study addressed the urgent need for a systems-level approach to port cybersecurity risk analysis by leveraging Fuzzy Cognitive Mapping (FCM) as a structured and transparent modeling technique. Through expert-driven concept modeling and a quantitative analysis of influence dynamics, the FCM framework enabled the identification of high-impact components and the visualization of systemic interdependencies across 19 critical factors grouped into four risk domains. The separate application of scenario configurations and simulation procedures allowed for an in-depth exploration of how specific threats-such as insider activity or legacy system removal-affect the cybersecurity landscape. These analyses revealed that while modernization reduces technical vulnerabilities, it can unintentionally amplify risks rooted in policy gaps, organizational fragmentation, and user behavior. The core contribution of this study lies in its methodological integration of FCM and simulations to produce a scalable, decision-oriented tool for cybersecurity risk governance in ports. Overall, this research advances a practical, systems-oriented framework for identifying, understanding, and mitigating cyber risk in maritime infrastructure, enabling more strategic and resilient cybersecurity planning.
Endoscopic Management of Cystic Stump Leaks: Insights From a Tertiary Care Center
(Turkish Assoc Trauma Emergency Surgery, 2025) Aslan, Firat; Bozkurt, Halil Alper; Yilmaz, Abdullah Hilmi; Binici, Serhat
BACKGROUND: Cystic stump leakage is the most common cause of bile leakage following cholecystectomy, representing a significant postoperative complication that requires prompt intervention. Currently, endoscopic treatment is the preferred management approach. This study aims to identify factors influencing the success of endoscopic therapy for cystic stump leaks by analyzing cases treated at our institution. METHODS: Thirty-seven patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) for cystic stump leakage were included in this study. Patient demographics, associated complications, and length of hospital stay were analyzed. RESULTS: All patients showed clinical improvement, with a mean hospital stay of 5.1 days. The presence of comorbidities, emergency surgery, or conversion to open surgery did not significantly impact treatment efficacy. Post-procedure, percutaneous drainage was required in 10 patients (27%). Procedure-related pancreatitis was noted in one patient (2.7%). Statistical analysis revealed that both the need for percutaneous drainage and the length of hospital stay were significantly lower in patients who had pre-existing drains (p<0.03). Additionally, early ERCP was associated with a significantly shorter hospital stay (p<0.01). CONCLUSION: Stent placement via ERCP is a safe and effective strategy for managing cystic stump leaks. Early ERCP intervention following cystic stump leak detection is recommended. Furthermore, percutaneous drainage may be necessary in patients who do not respond adequately to initial treatment.

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