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18β-Glycyrrhetinic Acid-Loaded Silver Nanoparticles Mitigate Neuroinflammation and Endoplasmic Reticulum Stress in the Brain Tissue of Diabetic Rats
(Mashhad University of Medical Sciences, 2026) Parlak, Secil Nazife; Yakut, Seda; Kara, Adem; Demir, Ozlem; Sebin, Saime Ozbek
Objective(s): Diabetes mellitus (DM) causes oxidative stress, neuroinflammation, and endoplasmic reticulum (ER) dysfunction that contribute to neurodegeneration. This study investigated the effects of 18 beta-glycyrrhetinic acid-loaded silver nanoparticles (18 beta-GA-AgNPs) on brain injury in diabetic rats. Materials and Methods: Fifty-six male Wistar rats were divided into eight groups: Sham, 18 beta-GA, AgNPs, 18 beta-GA-AgNPs, DM, DM+18 beta-GA, DM+AgNPs, and DM+18 beta-GA-AgNPs. Diabetes was induced by alloxan (120 mg/kg, IP), and treatments were administered orally for 14 days. Biochemical markers (MDA, GSH, SOD), histopathology, and expression of ER stress and apoptotic proteins (ATF6, IRE1, Caspase-3, BCL-2, CREB, TNF-alpha, and IL-1 beta) were evaluated. Results: The DM group exhibited significant increases in MDA, TNF-alpha, IL-1 beta, ATF6, and Caspase-3 with reduced GSH, SOD, and BCL-2, indicating oxidative stress, inflammation, apoptosis, and ER stress. In contrast, IRE1 levels remained unchanged in DM rats but showed a slight elevation in the AgNPs group. Treatment with 18 beta-GA-AgNPs markedly reduced MDA, TNF-alpha, IL-1 beta, ATF6, and Caspase-3, while restoring GSH, SOD, BCL-2, and CREB expression. Histopathological analysis confirmed neuronal apoptosis and perivascular and extracellular space enlargement in DM rats, whereas 18 beta-GA-AgNPs substantially attenuated these changes. Overall, 18 beta-GA-AgNPs provided synergistic neuroprotection by suppressing oxidative stress, inflammation, and ER stress while enhancing antioxidant and anti-apoptotic defenses. Conclusion: These findings suggest that 18 beta-GA-AgNPs may represent a promising therapeutic strategy against diabetes-associated neurodegeneration, although further long-term, ultrastructural, and sex-inclusive studies are warranted.
Citation - WoS: 5
Citation - Scopus: 4
3-Aminobenzamide Multifunctional Nanoparticles Enhances Anticancer Activity of Low-Dose Cisplatin Chemotherapy in Lung Adenocarcinoma
(Elsevier, 2024) Kaci, Fatma Necmiye; Daglioglu, Cenk
Chemotherapy is one of the main treatment methods for cancer patients, but its effectiveness is limited by drug resistance. Combining a chemotherapeutic agent with targeted molecular therapy may improve the curative effect of the chemotherapeutic agent. In this study, we investigate the efficacy of combining a 3-Aminobenzamide (3AB)-linked multifunctional platform with low-dose cisplatin chemotherapy aiming to modulate poly [ADP-ribose] polymerase 1 (PARP1) function in DNA repair to increase cytotoxic activity of the platinum-based cisplatin. The structure of the synthesized nanoplatforms was characterized by several physicochemical techniques, including dynamic light scattering (DLS), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and an in vitro pH-dependent release study. Cellular uptake experiments demonstrated preferentially targeted delivery of nanoparticles in lung carcinoma A549 cells, whereas the cellular uptake capacity was minimal in normal lung BEAS-2B cells. On the other hand, cytotoxicity experiments showed a reduction of cancer cell viability compared to free formulations. Furthermore, the combination treatment was examined by detecting the loss of mitochondrial membrane potential and the apoptotic cell population, confirming the treatment's functional involvement in apoptosis. Soft agar colony formation and cell invasion tests were also performed to detect the cancer cell's tumorigenic potential, confirming the synergistic effect of this combination in the reduction of tumorigenicity. Moreover, we analyzed the expression profiles of three candidate genes, which play important roles in cancer initiation, promotion and progression. Cell biology experiments indicated that this novel combination treatment possesses significant synergy between 3AB and low-dose cisplatin and is promising for development as an antitumor treatment for lung cancer.
Citation - WoS: 28
Citation - Scopus: 31
3-D Non-Linear Stress Analysis on the Adhesively Bonded Composite Joint Under Bending Moment
(Pergamon-Elsevier Science Ltd, 2014) Akpinar, Salih; Aydin, Murat Demir
This paper presents an approach to predict the three-dimensional effects (anti-clastic, free edge and bending-twisting coupling effects) and to assess the effects of the fiber orientation angle of the laminates on the stress distributions and the failure prediction in the Single Lap Composite Joints (SLJs) subjected to a bending moment via a 3-D non-linear finite element method. In the analysis, the composite adherends (AS4/3501-6) with five different fiber orientation angles ([901 +/- 45/0](2s), [0/90](4s), [45-45](4s), [0](16) and [90](16)) were assumed to behave as linearly elastic materials while the adhesive layer (FM 73) was assumed to be nonlinear. Also, the nonlinear geometric deformations of the SLJs were also taken into account. Consequently, it is seen that the state of stress in the vicinity of the free edge of the joint is fully three dimensional which has not been taken into account in any classical theory so far and the normal and shear stress distributions are extremely sensitive to this three-dimensional effects. From this aspect, the three-dimensional finite element analysis is a necessity for understanding explicitly the stress and failure states. Also, for both the adherends and the adhesive layer, the ply stacking sequence has a significant effect on the stress distribution and the failure. (C) 2014 Elsevier Ltd. All rights reserved.
Citation - WoS: 22
Citation - Scopus: 25
Accessibility of Vaccination Centers in COVID-19 Outbreak Control: A GIS-Based Multi-Criteria Decision Making Approach
(MDPI, 2021) Alemdar, Kadir Diler; Kaya, Omer; Codur, Muhammed Yasin; Campisi, Tiziana; Tesoriere, Giovanni
The most important protective measure in the pandemic process is a vaccine. The logistics and administration of the vaccine are as important as its production. The increasing diffusion of electronic devices containing geo-referenced information generates a large production of spatial data that are essential for risk management and impact mitigation, especially in the case of disasters and pandemics. Given that vaccines will be administered to the majority of people, it is inevitable to establish vaccination centres outside hospitals. Site selection of vaccination centres is a major challenge for the health sector in metropolitan cities due to the dense population and high number of daily cases. A poor site selection process can cause many problems for the health sector, workforce, health workers, and patients. To overcome this, a three-step solution approach is proposed: (i) determining eight criteria using from the experience of the advisory committee, (ii) calculating criterion weights using Analytic Hierarchy Process (AHP), and performing spatial analysis of criteria using Geographic Information System (GIS), (iii) assigning potential vaccination centres by obtaining a suitability map and determining service areas. A case study is performed for Bagcilar, Istanbul district, using the proposed methodology. The results show that the suitable areas are grouped in three different areas of the district. The proposed methodology provides an opportunity to execute a scientific and strategic vaccination programme and to create a map of suitable vaccination centres for the countries.
Citation - WoS: 13
Citation - Scopus: 17
Accurate Estimation of T Year Extreme Wind Speeds by Considering Different Model Selection Criterions and Different Parameter Estimation Methods
(Pergamon-Elsevier Science Ltd, 2018) Tosunoglu, Fatih
Accurate estimation of extreme wind speeds for different return periods is necessary to avoid extensive costs or large damages. To achieve this aim, the probability distribution of the wind speed data should be well defined and its parameters should be more precisely estimated. In this study, the commonly used probability distributions, including Gamma, Generalized Extreme Value, Logistic, Lognormal, Normal and Weibull, are fitted to annual maximum wind speed data in Turkey. Parameters of the fitted distributions are estimated using method of moments (MOM), method of maximum likelihood (MLM) and method of probability weighted moments (PWMs). Based on various model selection criterions (Akaike Information Criterion, Bayesian Information criterion, Anderson-Darling, Cramer-von-Mises, and Kolmogorov-Smirnov tests), the Generalized Extreme Value and Logistic, which provided the best fit for 40% and 30% of the series, respectively, were mostly found to be the most suitable distributions. Additionally, the Lognormal, Normal and Gamma distributions showed the best fit for 15%, 10% and 5% of the series, respectively. Moreover, the MLM and PWMs provided better parameter estimations for 57% and 30% the best fitted distributions, respectively. Furthermore, wind speed quantiles with the standard errors in various return periods were estimated using the best fitted distributions. (C) 2018 Elsevier Ltd. All rights reserved.
Citation - WoS: 137
Citation - Scopus: 144
Acetylcholinesterase and Carbonic Anhydrase Inhibitory Properties of Novel Urea and Sulfamide Derivatives Incorporating Dopaminergic 2-Aminotetralin Scaffolds
(Pergamon-Elsevier Science Ltd, 2016) Ozgeris, Bunyamin; Goksu, Suleyman; Kose, Leyla Polat; Gulcin, Ilhami; Salmas, Ramin Ekhteiari; Durdagi, Serdar; Supuran, Claudiu T.
In the present study a series of urea and sulfamide compounds incorporating the tetralin scaffolds were synthesized and evaluated for their acetylcholinesterase (AChE), human carbonic anhydrase (CA, EC 4.2.1.1) isoenzyme I, and II (hCA I and hCA II) inhibitory properties. The urea and their sulfamide analogs were synthesized from the reactions of 2-aminotetralins with N,N-dimethylcarbamoyl chloride and N,N-dimethylsulfamoyl chloride, followed by conversion to the corresponding phenols via O-demethylation with BBr3. The novel urea and sulfamide derivatives were tested for inhibition of hCA I, II and AChE enzymes. These derivatives exhibited excellent inhibitory effects, in the low nanomolar range, with K-i values of 2.61-3.69 nM against hCA I, 1.64-2.80 nM against hCA II, and in the range of 0.45-1.74 nM against AChE. In silico techniques such as, atomistic molecular dynamics (MD) and molecular docking simulations, were used to understand the scenario of the inhibition mechanism upon approaching of the ligands into the active site of the target enzymes. In light of the experimental and computational results, crucial amino acids playing a role in the stabilization of the enzyme-inhibitor adducts were identified. (C) 2016 Elsevier Ltd. All rights reserved.
Citation - WoS: 10
Citation - Scopus: 11
Acgc: Adaptive Chrominance Gamma Correction for Low-Light Image Enhancement
(Academic Press Inc. Elsevier Science, 2025) Severoglu, N.; Demir, Y.; Kaplan, N. H.; Kucuk, S.
Capturing high-quality images becomes challenging in low-light conditions, often resulting in underexposed and blurry images. Only a few works can address these problems simultaneously. This paper presents a low- light image enhancement scheme based on the Y-I-Q transform and bilateral filter in least squares, named ACGC. The method involves applying a pre-correction to the input image, followed by the Y-I-Q transform. The obtained Y component is separated into its low and high-frequency layers. Local gamma correction is applied to the low-frequency layers, followed by contrast limited adaptive histogram equalization (CLAHE), and these layers are added up to produce an enhanced Y component. The remaining I and Q components are also enhanced with local gamma correction to provide images with amore natural color. Finally, the inverse Y-I-Q transform is employed to create the enhanced image. The experimental results demonstrate that the proposed approach yields superior visual quality and more natural colors compared to the state-of-the-art methods.
Citation - WoS: 31
Citation - Scopus: 32
Acute and Chronic Effects of Aerobic Exercise on Serum Irisin, Adropin, and Cholesterol Levels in the Winter Season: Indoor Training Versus Outdoor Training
(Wolters Kluwer Medknow Publications, 2020) Ozbay, Serhat; Ulupinar, Suleyman; Sebin, Engin; Altinkaynak, Konca
The aim of this study is to investigate the acute and chronic effects of aerobic training performed indoors and outdoors on irisin, adropin, and cholesterol levels in winter. Thirty-two healthy males participated in this study. Participants were divided into two groups: outdoor group (n = 16) and indoor group (n = 16). They then performed 40-min aerobic running exercises 4 days/week for 18 weeks. The outdoor group trained at -5 degrees C-5 degrees C environmental temperature, while the indoor group trained at 21 degrees C-25 degrees C. Blood samples were collected before and after the 18-week training period and immediately after the first training. The results showed that single aerobic exercise induced minimal increase in serum irisin concentrations in both groups. In addition, irisin levels did not change in the outdoor group but significantly decreased in the indoor group after the 18-week training period. Aerobic exercise had no acute or chronic effects on serum adropin levels in the indoor group. However, the aerobic training caused a decrease in adropin levels chronically, but there was no acute effect after single aerobic exercise in the outdoor group. Furthermore, there was no acute effect on high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, and total cholesterol after single aerobic exercise in both groups. However, after the 18-week training period, there was a significant increase in HDL-C levels in both groups. Moreover, the increase in HDL-C in the outdoor group was higher than in the indoor group. Thus, this study provides evidence for the beneficial chronic effects of aerobic exercise and cold on HDL-C levels as well as the beneficial acute effects on irisin concentrations.
Citation - WoS: 7
Citation - Scopus: 7
The Acute Effects of Hip Thrust and Glute Bridge Exercises with Different Loads on Sprint Performance and Horizontal Force-Velocity Profile in Adolescent Soccer Players: A Post-Activation Performance Enhancement Approach
(Wiley, 2025) Cabuk, Salih; Ince, Izzet
This study examines the acute effects of post-activation performance enhancement (PAPE) with different loads (84% and 60% 1-RM) and exercises (hip thrust; HT and glute bridge; GB) on sprint performance (SP) and horizontal force-velocity (HF-V) profile components in adolescent male soccer players. The participants were randomly assigned to three groups: hip thrust group (HTG; n = 13), glute bridge group (GBG; n = 13), and control group (CG; n = 14). Sprint tests at distances of 10, 20, and 30 m were conducted pre-PAPE and post-PAPE protocols with a 7 min rest period. HTG and GBG executed HT and GB exercises at 84% and 60% of their 1-RM loads. Hedge's g was computed to assess within-group (pre-PAPE vs. post-PAPE) comparisons (Within-ES) and between-group (post-PAPE protocols) comparisons (Between-ES). PAPE protocols at 84% and 60% 1-RM loads demonstrated moderate effects on F0rel, Pmaxrel, FVslope, and DRF and small effects on V0, RFmax, and S20m in both HTG and GBG. Conversely, the CG exhibited trivial effects across parameters. Compared to the HTG 84% 1-RM protocol, the GBG 84% 1-RM protocol showed small effects on V0 and S10m. The HTG 60% 1-RM protocol had a small effect on RFmax compared to both GBG 84% and 60% 1-RM protocols. Both HTG and GBG 84% and 60% 1-RM protocols demonstrated small effects on S30m compared to the CG. These findings suggest that GB exercises may offer a viable alternative to HT exercises for eliciting PAPE effects, particularly in enhancing SP and related mechanics in adolescent soccer players.
Citation - WoS: 1
Citation - Scopus: 1
Acute Effects of Nordic Hamstring Exercise on Hamstring Stiffness: A Randomised Controlled Trial
(MDPI, 2025) Yagiz, Gokhan; Monleon, Cristina; Akaras, Esedullah; Adanir, Sena; Liebana, Encarnacion
Background: This study aimed to examine the immediate effects of the Nordic Hamstring Exercise (NHE) on the stiffness of the biceps femoris (BF) and semitendinosus (ST) muscles. Methods: This parallel-group randomised controlled trial followed CONSORT 2025 guidelines. Twenty-four physically active adults (16 females, 8 males) were randomly assigned to an NHE group (n = 12) or a control group (n = 12) using 1:1 gender-stratified randomisation. The NHE group performed 3 sets of 10 repetitions of the NHE, while the control group remained inactive. Muscle stiffness of the BF and ST was assessed pre- and post-intervention using the MyotonPro device. Results: No significant overall changes in hamstring stiffness were observed within or between groups (p > 0.05). Within the NHE group, the ST tended to increase in stiffness (11.25 N/m, p = 0.057), while the BF showed a small, non-significant reduction (-12.00 N/m, p = 0.696). The difference in changes between BF and ST was significant (p = 0.039). Independent of group allocation, males demonstrated significantly higher baseline stiffness than females for BF (258.13 vs. 195.81 N/m, p < 0.001) and for ST (247.88 vs. 174.00 N/m, p = 0.003). Regression analysis showed that only height predicted the change in ST stiffness after NHE (R = 0.625, R-2 = 0.39, p = 0.030). Conclusions: A single NHE session did not alter overall hamstring stiffness but produced opposite, muscle-specific effects. More research with larger, uniform samples is needed to confirm these findings.
Citation - WoS: 3
Citation - Scopus: 4
Acute Effects of Three Different Stretching Techniques on Hamstring Flexibility in Professional Football Players
(Gdansk Univ Physical Education & Sport, 2023) Erol, Erkan; Yildiz, Ramazan; Yildiz, Aye; Dogan, Fatih Emre; Elbasan, Buelent
Introduction: Hamstring injuries are common in physically active people and athletes. Lack of hamstring flexibility is the one of the most important characteristics of hamstring injuries in athletes. The aim of this study was to investigate effects of three different stretching techniques on hamstring flexibility in professional football players. Materials and Methods: Fifty-five male football players between the ages of 18-20 years old were involved in the study. The participants were divided into 3 groups: static stretching, neuromobilization and Mulligan traction straight leg raise (TSLR), respectively. Each participant's dominant lower extremity was assessed with a straight leg raise test (SLR) using a goniometer before and after the intervention. Results: There was a significant difference in the SLR range of motion before and after the intervention in all groups. There was no difference in the range of SLR between the groups at the beginning and at the end. However, the increase in the SLR range of motion was significantly higher in the Mulligan TSLR group. Conclusions: It was concluded that all 3 stretching techniques are effective in increasing hamstring flexibility in football players. However, the Mulligan TSLR technique could provide a greater increase in the range of motion than other techniques.
Citation - WoS: 1
Adaptation Levels and Expectations of Students with Disabilities in Physical Education and Sports Departments of Universities
(Ankara University, Fac Educational Sciences, 2019) Namli, Sevinc; Suveren, Sibel
This research aims to determine the adaptations and expectations of the students with disabilities, who study in the physical education and sports departments, to their deparments. The research, which is composed of explanatory sequential design out of the mixed approach designs and in which quantitative and qualitative approaches are used together, were made with the participation of all the students with disabilities studying in physical education and sports departments of 21 universities in Turkey during 2015-2016 academic year. 71 students including 27 with visual impairments, 9 with hearing impairments and 38 with physically impairments participated in the quantitative section of the research. 11 students including 4 with visually impairments, 3 with hearing impairments and 4 with physically impairments participated in the qualitative section. "Adaptation Scale of Students with Disabilities Studying in Physical Education and Sports Departments" and "Semi-structured Interview Form" were used as data collection tools. While the participants with visually impairments and physically impairments emphasized the issue of organizing the physical areas and problems in the practical lessons, the participants with hearing impairments were found to have problems in theoretical lessons. It was determined that the students with disabilities have common expectations, such as instructors sparing more time for them during the lessons.
Citation - WoS: 4
Citation - Scopus: 4
Adaptation of Symbolic Discrete Control Synthesis for Energy-Efficient Multi-Pocket Milling
(MDPI, 2024) Caska, Serkan; Ozbaltan, Mete
In engineering, cost minimization, especially in Computer Numerical Control (CNC) machining like pocket milling, is crucial. Existing tool path definition software often lacks optimization, particularly at critical starting and ending points. This study optimizes CNC machine tool paths for energy-efficient multi-pocket milling, utilizing the Symbolic Discrete Control Synthesis (SDCS) method for formal correctness. In our work, the tool path generation is formulated as a traveling salesman problem. We introduce a modeling framework to adapt SDCS to multi-pocket-milling processes, aiming to enhance precision and efficiency for potential cost savings, including energy and time, in engineering applications. This study reports experimental and comparative results, where comparative evaluations were made using metaheuristic algorithms. Our proposed approach improves CNC machining processes for multi-pocket milling. We experimentally evaluate our control algorithms and demonstrate and validate our approach through case studies.
Citation - WoS: 1
Citation - Scopus: 1
Adaptive Event Triggered Control of Nonholonomic Mobile Robots
(Springer International Publishing AG, 2021) Guzey, Mehmet
In this paper, the design of adaptive regulation control of mobile robots in the presence of uncertain robot dynamics and with event-based feedback is presented. Two-layer neural networks (NN) are utilized to represent the uncertain nonlinear dynamics of the mobile robots, which is subsequently employed to generate the control torque with event-sampled measurement update. Relaxing the perfect velocity tracking assumption, control torque is designed to minimize the velocity tracking error, by explicitly taking into account the dynamics of the robot. The Lyapunov's stability method is utilized to develop an event-sampling condition and to demonstrate the regulation performance of the mobile robot. Finally, simulation results are presented to verify theoretical claims and to demonstrate the reduction in the computations with event-sampled control execution.
Citation - WoS: 107
Citation - Scopus: 114
Additive Manufacturing of Multiple Layered Materials (Ti6Al4V/316L) and Improving Their Tribological Properties with Glow Discharge Surface Modification
(Pergamon-Elsevier Science Ltd, 2021) Tekdir, H.; Yetim, A. F.
Selective Laser Melting (SLM), which is a kind of laser powder bed fusion additive manufacturing technology, is commonly used in the manufacturing of AISI 316L stainless steel components. This study aims to enhance the mechanical and tribological properties of 316L manufactured by using SLM and plasma oxidation treatment in a glow discharge atmosphere. For that reason, Ti6Al4V layers were formed on 316L stainless steel samples by selective laser melting. Samples with a duplex structure (316L substrate and Ti6Al4V layer) were oxidized at 650 degrees C and 750 degrees C for 1 h and 4 h in the plasma atmosphere. The characterization of the formed Ti6Al4V and oxide layers is determined by the Vickers micro-hardness tester, scanning electric microscope, 3D profilometer, Energy dispersive X-ray spectrometer, and X-ray diffractometer. Wear tests were performed against Al2O3 balls under a load of 10 N, dry sliding ambient air conditions by a pin-on-disk tribometer. It was observed that the hardness and wear resistance of Ti6Al4V layered and plasma-oxidized samples were better than the uncoated 316L samples due to the formation of titanium oxide phases and diffusion zone depth. The best wear resistance is obtained in the sample with the highest hardness value.
Adherence to the Mediterranean Diet in Adults: The Role of Environmental and Sustainable Food Literacy
(BMC, 2025) Ozata-Uyar, Gizem; Aslan, Serkan; Camli, Ayse; Arslan, Merve; Bozkurt, Osman; Kocaadam-Bozkurt, Betul
AimThis study aimed to evaluate the relationship between environmental literacy, sustainable food literacy, and adherence to the Mediterranean diet (MD) in adults.MethodData were collected via a web-based questionnaire created using Google Forms between April and August 2024 in Erzurum, Turkey. A total of 394 adults participated through snowball sampling. The questionnaire included sections on demographic information, anthropometric measurements, the Environmental Literacy Scale for Adults (ELSA), the Sustainable Food Literacy Scale (SFLS), and the Mediterranean Diet Adherence Screener (MEDAS).Results38.6% of the participants were found to adhere to the Mediterranean Diet (MD). Married participants were more likely to have adhered to the MD than single ones (odds ratio [OR]:0.41, p = 0.006). Adherence to the MD was associated with higher education duration (OR = 1.05, p = 0.011), a higher SFLS total score (OR = 1.01, p = 0.025), and a higher ELSA score (OR = 1.04, p = 0.004).ConclusionThe MD is a sustainable dietary model that enhances health and is environmentally friendly. For this reason, it may be possible to direct society towards healthier and less environmentally damaging food choices through training to increase individuals' sustainable literacy and environmental literacy levels.
Citation - WoS: 18
Citation - Scopus: 19
Adhesion and Multipass Scratch Characterization of Ti:Ta-DLC Composite Coatings
(Elsevier Science Sa, 2018) Cicek, Hikmet; Keles, Aysenur; Totik, Yasar; Efeoglu, Ihsan
DLC (diamond like carbon) is one of the most studied coatings due to its excellent mechanical and tribological properties, desirable chemical inertness and high corrosion resistance hence it has been widely used in industrial applications for a long time. However, low adhesion and low fatigue resistance are disadvantages of this coating. In this study, we deposited Ti:Ta doped DLC graded-composite coatings on Ti6Al4V and M2 substrates and adhesion and multipass scratch behaviors were characterized. SEM, EDAX and XRD were used to determine the structural properties. Adhesion and fatigue-like behaviors were obtained by scratch tests. The results showed that the critical loads and fatigue resistance of the coatings were affected by the target currents and the hardness of the coatings and substrate.
Citation - WoS: 2
Citation - Scopus: 2
Advanced Hybrid Modeling of Cementitious Composites Using Machine Learning and Finite Element Analysis Based on the CDP Model
(MDPI, 2025) Agcakoca, Elif; Jueyendah, Sebghatullah; Yaman, Zeynep; Sumer, Yusuf; Maali, Mahyar
This study aims to investigate the mechanical behavior of cement mortar and concrete through a hybrid approach that integrates artificial intelligence (AI) techniques with finite element modeling (FEM). Support Vector Machine (SVM) models with Radial Basis Function (RBF) and polynomial kernels, along with Multilayer Perceptron (MLP) neural networks, were employed to predict the compressive strength (Fc) and flexural strength (Fs) of cement mortar incorporating nano-silica (NS) and micro-silica (MS). The dataset comprises 89 samples characterized by six input parameters: water-to-cement ratio (W/C), sand-to-cement ratio (S/C), nano-silica-to-cement ratio (NS/C), micro-silica-to-cement ratio (MS/C), and curing age. Simultaneously, the axial compressive behavior of C20-grade concrete was numerically simulated using the Concrete Damage Plasticity (CDP) model in ABAQUS, with stress-strain responses benchmarked against the analytical models proposed by Mander, Hognestad, and Kent-Park. Due to the inherent limitations of the finite element software, it was not possible to define material models incorporating NS and MS; therefore, the simulations were conducted using the mechanical properties of conventional concrete. The SVM-RBF model demonstrated the highest predictive accuracy with RMSE values of 0.163 (R2 = 0.993) for Fs and 0.422 (R2 = 0.999) for Fc, while the Mander model showed the best agreement with experimental results among the FEM approaches. The study demonstrates that both the SVM-RBF and CDP-based modeling approaches serve as robust and complementary tools for accurately predicting the mechanical performance of cementitious composites. Furthermore, this research addresses the limitations of conventional FEM in capturing the effects of NS and MS, as well as the existing gap in integrated AI-FEM frameworks for blended cement mortars.
Citation - WoS: 7
Citation - Scopus: 9
Advanced Mini Solar Still Design: Spiral Heating, Triangular Prism Condensation, and Comprehensive Energy-Exergy Analysis
(Elsevier, 2025) Afshari, Faraz; Kose, Murat; Akyurek, Eda Feyza; Mandev, Emre
Improving solar distillation systems is crucial in addressing water scarcity by providing a sustainable solution for clean water production, while also harnessing renewable energy to reduce environmental impact and reliance on conventional power sources. In solar still systems, salt water is typically contained in a basin, where it is heated by solar energy to produce distilled water through evaporation and condensation procedure. However, traditional systems do not allow for precise control over the temperature of the saltwater. This study introduces a novel approach by integrating a spiral type solar heater for salt water heating, which elevates the saltwater temperature to higher levels. To implement the proposed set up, the integration of a spiral-type solar heater, cotton-based materials, and a perforated pipe for delivering heated saltwater should be adopted, along with intermittent water pump operation to optimize heat absorption and evaporation efficiency. This enhancement enables more efficient condensation, which is achieved using a long triangular prism condensation unit. From the obtained results, it was revealed that the proposed mini solar still system can be modified by using cotton base materials and dripping salt water from a perforated pipe can enhance the distilled water by 138.46%. Comparing the energy efficiency results shows a significant 128.57 % efficiency improvement, highlighting the need to optimize strategies and modifications for better solar distillation performance. Comparing the optimal experiment with the reference experiment revealed a substantial 152.63 % increase in exergy efficiency.
Citation - WoS: 1
Citation - Scopus: 1
Advancing Pulmonary Embolism Detection with Integrated Deep Learning Architectures
(Springer, 2025) Biret, Can Berk; Gurbuz, Sukru; Akbal, Erhan; Baygin, Mehmet; Ekingen, Evren; Derya, Serdar; Tuncer, Turker
The main aim of this study is to introduce a new hybrid deep learning model for biomedical image classification. We propose a novel convolutional neural network (CNN), named HybridNeXt, for detecting pulmonary embolism (PE) from computed tomography (CT) images. To evaluate the HybridNeXt model, we created a new dataset consisting of two classes: (1) PE and (2) control. The HybridNeXt architecture combines different advanced CNN blocks, including MobileNet, ResNet, ConvNeXt, and Swin Transformer. We specifically designed this model to combine the strengths of these well-known CNNs. The architecture also includes stem, downsampling, and output stages. By adjusting the parameters, we developed a lightweight version of HybridNeXt, suitable for clinical use. To further improve the classification performance and demonstrate transfer learning capability, we proposed a deep feature engineering (DFE) method using a multilevel discrete wavelet transform (MDWT). This DFE model has three main phases: (i) feature extraction from raw images and wavelet bands, (ii) feature selection using iterative neighborhood component analysis (INCA), and (iii) classification using a k-nearest neighbors (kNN) classifier. We first trained HybridNeXt on the training images, creating a pretrained HybridNeXt model. Then, using this pretrained model, we extracted features and applied the proposed DFE method for classification. The HybridNeXt model achieved a test accuracy of 90.14%, while our DFE model improved accuracy to 96.35%. Overall, the results confirm that our HybridNeXt architecture is highly accurate and effective for biomedical image classification. The presented HybridNeXt and HybridNeXt-based DFE methods can potentially be applied to other image classification tasks.

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