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Factors Influencing the Transition Time From Psoriasis to Psoriatic Arthritis: A Real-World Multicenter Analysis
(Springer Heidelberg, 2025) Kilic, Gamze; Kilic, Erkan; Tekeoglu, Ibrahim; Sargin, Betul; Cengiz, Gizem; Balta, Nihan Cuzdan; Nas, Kemal; 01. Atılım University
To identify clinical and demographic predictors associated with the timing of transition from psoriasis (PsO) to psoriatic arthritis (PsA), and to compare the characteristics of patients with concurrent PsO-PsA onset versus those with prolonged transition. A multi-center, observational study was conducted using data from the Turkish League Against Rheumatism (TLAR) network including PsA patients fulfilling CASPAR criteria. Patients were categorized into two groups: Group 1 (concurrent PsO and PsA onset within +/- 1 year) and Group 2 (prolonged transition to PsA, > 1 year after PsO). Demographic, clinical, and laboratory characteristics, disease activity, and patient-reported outcomes were compared between groups. Logistic regression was employed to determine independent predictors of prolonged transition. Among 799 patients (mean age 46.8 +/- 12.3 years), 237 (29.7%) had concurrent onset and 562 (70.3%) had a prolonged transition, with a mean PsO-to-PsA interval of 12.9 +/- 9.6 years. Depression (p = 0.005) and fatigue levels (p = 0.011) were significantly higher in patients with prolonged transition to PsA. Multivariate analysis revealed that scalp psoriasis (OR = 7.162), nail psoriasis (OR = 3.270), family history of PsO (OR = 1.813), and enthesitis ever (OR = 2.187) were associated with prolonged transition. Conversely, family history of PsA (OR = 0.421) and older age at PsO onset (OR = 0.957) predicted shorter transition. Prolonged transition from PsO to PsA is influenced by distinct clinical and demographic factors. Scalp/nail psoriasis, family history of PsO, and enthesitis ever may signal higher risk for prolonged PsA onset. Recognizing these markers can support timely referral and intervention, minimizing diagnostic delay and improving long-term patient outcomes.
Space Efficiency in Tall Timber Buildings: A Comprehensive Review
(Highlights of Science, 2025) Ilgin, Huseyin Emru; Aslantamer, Ozlem Nur; Interior Architecture and Environmental Design; 03. School of Fine Arts Design & Architecture; 01. Atılım University
Tall timber construction is gaining popularity due to its notable environmental and economic benefits throughout its lifecycle. Maximizing space efficiency in these buildings is a key factor in ensuring project viability. However, there has been a lack of comprehensive research on the space efficiency of these projects. This study focused on analyzing 50 tall buildings (over eight stories) globally to improve insights into the design elements that affect space use. The key findings include: i) predominant architectural configurations incorporate residential functions, a centrally positioned core, and prismatic building forms; ii) composite materials are the most utilized, with shear-walled frame systems being the preferred structural solution; and iii) average space efficiency is 84%, with core areas accounting for 11% of the gross floor area, ranging from 71% and 4% at the lower end to 93% and 21% at the upper end. This study provides valuable guidance for architects and other key participants engaged in the planning and construction of tall timber buildings.
Influence of Synthesis Parameters on the Structural Formation of Mayenite via the Citrate Sol-Gel Method
(Tubitak Scientific & Technological Research Council Turkey, 2025) Eryildirim, Busra; Oktar, Nuray; Dogu, Doruk; Metallurgical and Materials Engineering; 06. School Of Engineering; 01. Atılım University
Mayenite (Ca12Al14O33) has remarkable properties such as high oxygen mobility, ionic conductivity, and catalytic activity. It has many different applications, including oxide-conducting electrolytes, fluorescent lamps, moisture sensors, hydrogen-permeable membranes, oxygen pumps, hydrogen storage, and catalysis. However, pure and homogeneous mayenite synthesis parameters have not yet been fully explored. This study examines the effect of synthesis parameters including metal salt (MS) to citric acid (CA) molar ratios (1:1 and 1:2), pH (0.4-2), and calcination temperature (900-1200 degrees C) in citrate sol-gel method on the crystal structure of mayenite. Synthesized materials were examined by thermogravimetric (TG), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, N2 adsorption-desorption, scanning electron microscopy (SEM), inductively coupled plasma-optical emission spectrometry (ICP-OES), Fourier-transform infrared spectroscopy (FTIR), and pyridine adsorbed diffuse reflectance Fourier-transformed infrared spectroscopy (DRIFTS) analyses. The results show that all 3 parameters contribute to the mayenite phase formation and different impurity phases can be observed depending on the synthesis parameters. With no pH adjustment and an MS to CA ratio of 1, other phases of calcium aluminate mostly form. Mayenite becomes the main phase by doubling the CA amount. Besides CA, pH is also an important factor in mayenite synthesis. When the pH was adjusted to 2 with the MS to CA ratio at 1:1, mayenite was formed as the main phase, but other phases of calcium aluminate were also observed in the structure. XRD results show that all parameters studied influence the crystal structure of the final material, including the calcination temperature. This study shows that pure mayenite can be synthesized with a calcination temperature of 1200 degrees C, at a pH of 2, and the MS to CA molar ratio of 1:2.
Toxoplasma gondii Coinfection in HIV-Positive Patients at a Tertiary Care Hospital
(Bentham Science Publ Ltd, 2025) Kurkcu, Muhammed Furkan; Bakir, Ayfer; Kaba, Semiha Berra Topsakal; Kusabbi, Ilknur Alkan; Usluca, Selma; Basic Sciences; 08. Medical School; 01. Atılım University
Introduction: Toxoplasma gondii (T. gondii) can cause serious complications in both immunocompetent and immunosuppressed individuals. This study aims to assess the seroprevalence of T. gondii among HIV-positive individuals and to investigate its association with age, sex, CD4+ T cell count, HIV RNA levels, and hematological parameters. Methods: This study included 247 HIV-positive individuals followed up at a tertiary care hospital between November 1, 2022, and November 30, 2024. We analyzed serum samples for T. gondii IgG antibodies using electrochemiluminescent microparticle immunoassay. Results: The prevalence of T. gondii IgG seropositivity was found to be 32.8% (n=81; 95% CI: 26.9-39). The median age of seropositive individuals was 52 years (IQR: 42-61), which was significantly higher compared to seronegative individuals (p<0.001). The highest IgG seropositivity rate (66.7%) was observed in the 61-80 age group. Hemoglobin levels were significantly lower in IgG seropositive individuals (p=0.040). Logistic regression analysis indicated an increased risk of T. gondii infection with advancing age. The odds ratio for the 41-60 age group was 13.3 (95% CI: 1.6-106, p=0.02), while for the 61-80 age group, it was 28 (95% CI: 3.3-240, p=0.002). Discussion: The seroprevalence of T. gondii in HIV-positive individuals was lower than both global and regional averages. Age was identified as an independent risk factor for T. gondii seropositivity. Additionally, hematological alterations associated with anemia were observed in seropositive individuals. Further large-scale, multi-center, and regionally representative studies are required to optimize T. gondii infection management and screening strategies in people living with HIV. Conclusion: These findings suggest that T. gondii infection in HIV-positive individuals increases with age and may be associated with anemia, highlighting the need for age-focused screening and management strategies.
Citation - WoS: 1
Citation - Scopus: 1
Parameter Identification and Speed Control of a Small-Scale BLDC Motor: Experimental Validation and Real-Time PI Control with Low-Pass Filtering
(MDPI, 2025) Abouseda, Ayman Ibrahim; Doruk, Resat Ozgur; Amini, Ali; Electrical-Electronics Engineering; 06. School Of Engineering; 01. Atılım University
This paper presents a structured and experimentally validated approach to the parameter identification, modeling, and real-time speed control of a brushless DC (BLDC) motor. Electrical parameters, including resistance and inductance, were measured through DC and AC testing under controlled conditions, respectively, while mechanical and electromagnetic parameters such as the back electromotive force (EMF) constant and rotor inertia were determined experimentally using an AVL dynamometer. The back EMF was obtained by operating the motor as a generator under varying speeds, and inertia was identified using a deceleration method based on the relationship between angular acceleration and torque. The identified parameters were used to construct a transfer function model of the motor, which was implemented in MATLAB/Simulink R2024b and validated against real-time experimental data using sinusoidal and exponential input signals. The comparison between simulated and measured speed responses showed strong agreement, confirming the accuracy of the model. A proportional-integral (PI) controller was developed and implemented for speed regulation, using a low-cost National Instruments (NI) USB-6009 data acquisition (DAQ) and a Kelly controller. A first-order low-pass filter was integrated into the control loop to suppress high-frequency disturbances and improve transient performance. Experimental tests using a stepwise reference speed profile demonstrated accurate tracking, minimal overshoot, and robust operation. Although the modeling and control techniques applied are well known, the novelty of this work lies in its integration of experimental parameter identification, real-time validation, and practical hardware implementation within a unified and replicable framework. This approach provides a solid foundation for further studies involving more advanced or adaptive control strategies for BLDC motors.
Diagnostic Value of Thyroid Physical Examination in the Elderly and Comparison with Ultrasonography
(UK Scientific Publishing Ltd, 2025) Gulmez, Mehmet Ihsan; Aydin, Canset; Surgical Sciences; 08. Medical School; 01. Atılım University
This study is part of the health project called "Health screening for the elderly in Ankara" for patients aged 65 and over, with 1200 participants. Patients with missing laboratory tests (n = 59), movement disorders and/or bedridden (n = 54) were excluded from the study. PE was performed by a geriatrician or an ear, nose, and throat surgeon, and ultrasonographic evaluation was performed by a radiologist. PE and USG findings were compared. We aimed to investigate the diagnostic accuracy of physical examination (PE) of the thyroid gland (TG) in patients over 65 years of age and to assess the reliability by comparing PE with ultrasonographic (USG) examination. The median age of the patients participating in the study was 71.17. When the differences between thyroid nodules (TN), the number of TN size, and goiter detection were compared in terms of PE and USG, all values were statistically signifi- cant, and P values were < 0.001. The sensitivity of PE of TG was calculated as 31.0%. In our study, the sensitivity of PE of TG in terms of TN and goiter was found to below. The diagnostic accuracy of PE of TG is low, and therefore, its impact on clinical decision-making is limited. Furthermore, detected nodules rarely progress to clinically relevant disease, leading to overdiagnosis and overtreatment. Especially in groups at risk for nodules and malignancy, PE must be combined with imaging methods and, if necessary, pathological examination, even if nodules or goiter are not palpable in PE.
Physics-Informed Neural Network for Nonlinear Bending Analysis of Nano-Beams: A Systematic Hyperparameter Optimization
(MDPI, 2025) Esfahani, Saba Sadat Mirsadeghi; Fallah, Ali; Aghdam, Mohammad Mohammadi; 01. Atılım University
This paper investigates the nonlinear bending analysis of nano-beams using the physics-informed neural network (PINN) method. The nonlinear governing equations for the bending of size-dependent nano-beams are derived from Hamilton's principle, incorporating nonlocal strain gradient theory, and based on Euler-Bernoulli beam theory. In the PINN method, the solution is approximated by a deep neural network, with network parameters determined by minimizing a loss function that consists of the governing equation and boundary conditions. Despite numerous reports demonstrating the applicability of the PINN method for solving various engineering problems, tuning the network hyperparameters remains challenging. In this study, a systematic approach is employed to fine-tune the hyperparameters using hyperparameter optimization (HPO) via Gaussian process-based Bayesian optimization. Comparison of the PINN results with available reference solutions shows that the PINN, with the optimized parameters, produces results with high accuracy. Finally, the impacts of boundary conditions, different loads, and the influence of nonlocal strain gradient parameters on the bending behavior of nano-beams are investigated.
Modeling, Dynamic Characterization, and Performance Analysis of a 2.2 kW BLDC Motor Under Fixed Load Torque Levels and Variable Speed Inputs: An Experimental Study
(MDPI, 2025) Abouseda, Ayman Ibrahim; Doruk, Resat; Emin, Ali; Akdeniz, Ozgur; Automotive Engineering; 06. School Of Engineering; 01. Atılım University
Accurate modeling and performance analysis of brushless DC (BLDC) motors are essential for high-efficiency control in modern drive systems. In this article, a BLDC motor was modeled using system identification techniques. In addition, experimental data were collected from the BLDC motor, including its speed response to various input signals. Using system identification tools, particularly those provided by MATLAB/Simulink R2024b, an approximation model of the BLDC motor was constructed to represent the motor's dynamic behavior. The identified model was experimentally validated using various input signals, demonstrating its accuracy and generalizability under different operating conditions. Additionally, a series of mechanical load tests was conducted using the AVL eddy-current dynamometer to evaluate performance under practical operating conditions. Fixed load torques were applied across a range of motor speeds, and multiple torque levels were tested to assess the motor's dynamic response. Electrical power, mechanical power, and efficiency of the entire system were computed for each case to assess overall system performance. Moreover, the real-time state of charge (SOC) of Lithium-ion (Li-ion) battery was estimated using the Coulomb counting method to analyze the impact of Li-ion battery energy level on the BLDC motor efficiency. The study offers valuable insights into the motor's dynamic and energetic behavior, forming a foundation for robust control design and real-time application development.
W-Band RCS Prediction of Small Objects: Comparing Two Widely Used Methods with Experimental Validation
(Gazi Univ, 2025) Sezgin, Deniz; Yardim, Funda Ergun; Aydin, Elif; Kara, Ali; Department of Electrical & Electronics Engineering; Airframe and Powerplant Maintenance; 15. Graduate School of Natural and Applied Sciences; 13. School of Civil Aviation (4-Year); 01. Atılım University
This paper compares the accuracy of Shooting and Bouncing Rays and Electric Field Integral Equation methods for Radar Cross Section prediction of small objects at 77-81 GHz band. Existing studies on RCS prediction methods often lack comprehensive comparisons between computational and experimental results, particularly for small objects measured with a 77 GHz radar. This study addresses this gap by presenting an in-depth analysis of both simulation and measurement data. In this work, three targets with varying geometries and materials were measured with a frequency modulated continuous wave radar and simulated using Ansys HFSS and CST Studio Suite. The measurements were performed with a commercial off-the-shelf (COTS) frequency modulated continuous wave radar operating at 77-81 GHz. This study aims to emphasize the importance of considering both efficiency and accuracy when opting for an RCS prediction method. Overall, the outcomes of both methods have largely demonstrated good alignment. It has been noted that, while Shooting and Bouncing Rays method offers promising time-saving advantages, Electric Field Integral Equation method remains a valuable tool for complex geometries where precise results are crucial.
An Experimental Study on Ultrasonic-Assisted Drilling of CFRP Composites with Minimum Quantity Lubrication
(MDPI, 2025) Namlu, Ramazan Hakki; Sagener, Mustafa Burak; Kilic, Zekai Murat; Colak, Oguz; Kilic, Sadik Engin; Manufacturing Engineering; Mechanical Engineering; 06. School Of Engineering; 01. Atılım University
The increasing use of carbon fiber reinforced polymer (CFRP) composites in industries such as aerospace, due to its high strength-to-weight ratio, durability, and resistance to corrosion has led to a growing demand for more efficient machining processes. However, the multilayered structure of CFRP composites, composed of densely packed fibers, presents significant challenges during machining. Additionally, when cutting fluids are used to improve effective cooling and lubrication, the material tends to absorb the fluid, causing damage and leading to problem of weaking of composite structure. To address these issues, this study compares ultrasonic-assisted drilling (UAD) and minimum quantity lubrication (MQL) techniques with conventional drilling (CD) and dry cutting to improve the performance of CFRP composite drilling. The results show that using UAD and MQL together reduced thrust force by up to 27%, improved surface roughness inside the holes by up to 31%, reduced improved hole diameter, cylindricity, roundness, and delamination.
Feasibility Study of Chatter Suppression in Milling Through Internal Channels
(Springer London Ltd, 2025) Dogan, Hakan; Ozsoy, Muhammet; Namlu, Ramazan Hakki; Mechanical Engineering; 06. School Of Engineering; 01. Atılım University
Milling chatter significantly affects machining productivity, and methods to eliminate chatter caused by milling cutter dynamics are limited due to space constraints and the rotation of the milling cutter. This study investigates the impact of fluid-induced damping effect on chatter stability in milling operations and proposes it as an easy to implement and effective method to improve chatter stability caused by a cutter's vibration mode. The approach utilises a viscous fluid, silicone oil, filled into internal coolant channel of the cutting tool to improve stability by increasing the damping. Both modal and milling tests were conducted for the tool with and without silicone oil. The results show that stability can be significantly increased by this method presenting it as a viable chatter suppression technique. The results show a significant improvement in stability by presenting the method as a practical and cost-effective chatter suppression solution. Its ease of implementation makes it attractive for industrial use.
First-Principles Investigation of Kaolinite/YSZ Heterostructure for Solar-Driven Photocatalytic Hydrogen Production
(Pergamon-Elsevier Science Ltd, 2025) Park, Jongee; Yu, Eunmi; Fatima, Syeda Afrinish; Metallurgical and Materials Engineering; 06. School Of Engineering; 01. Atılım University
This work employs density functional theory (DFT) to elucidate the structural, electronic, and photocatalytic properties of a kaolinite/yttria-stabilized zirconia (Kaol/YSZ) heterostructure tailored for solar-driven hydrogen generation. The lattice mismatch between Kaol(001) and YSZ(111) was determined to be 4.4 % along the a-axis and 2.2 % along the b-axis. Two interface terminations were modeled: an O-terminated Si-O surface and an OH-terminated Al-OH surface. The OH-terminated interface demonstrated a stronger interfacial binding energy (-9.32 eV per cell) and enhanced thermodynamic stability, indicating its suitability for photocatalytic water splitting. Electronic structure analysis reveals that the Kaol/YSZ heterostructure exhibits a narrowed band gap of 1.46 eV relative to the isolated components, which promotes enhanced visible-light absorption. A type-II band alignment is observed, facilitating photoinduced electron transfer from the conduction band of YSZ to the conduction band of Kaol and promoting efficient charge separation. Hirshfeld charge analysis confirms the existence of a built-in electric field at the interface that further drives charge migration. Calculated optical absorption spectra shows a red shift in the heterostructure's absorption edge, extending its photoresponse into the visible region. Under simulated solar irradiation, photogenerated electrons preferentially migrate to Kaol for proton reduction, while holes remain on the YSZ surface to oxidize water, enabling simultaneous H2 evolution and O2 evolution pathways. These findings highlight the promise of the Kaol/YSZ heterostructure as a robust visible-light photocatalyst for sustainable hydrogen production and environmental remediation.
Ultrafast Green Synthesis of Superparamagnetic Hybrid Nanoparticle for Advanced Applications
(Wiley, 2025) Kibar, Gunes; 01. Atılım University
The integration of superparamagnetic iron oxide nanoparticles (SPIONs) into functional hybrid nanostructures remains a challenge, particularly in preserving their magnetic properties within composite frameworks. Herein, we present a rapid and environmentally friendly synthesis strategy for SPION-decorated polyhedral oligomeric silsesquioxane (POSS) nanoparticles. The process involves UV-induced polymerization to form POSS nanoparticles, followed by in situ SPION precipitation, with comprehensive characterization performed via SEM, FTIR, XRD, and VSM analyses. This approach enables the fabrication of hybrid nanoparticles (similar to 160 nm) within 5 min and subsequent SPION decoration in under an hour, ensuring (10 emu/g) superparamagnetic behavior. The developed method is highly scalable, efficient, and compatible with green chemistry principles, making it a promising platform for engineering advanced hybrid nanostructures. These nanoparticles hold significant potential for applications in biomedicine, catalysis, and next-generation material science.
Penta-Graphene/SnS2 Heterostructures with Z-Scheme Charge Transfer for Efficient Photocatalytic Water Splitting
(Amer Chemical Soc, 2025) Nasoz, Duygu Lale; Surucu, Ozge; Wang, Xiaotian; Surucu, Gokhan; Sarac, Yasemin; Gencer, Aysenur; Physics Group; Electrical-Electronics Engineering; 06. School Of Engineering; 01. Atılım University
The present study explores the photocatalytic potential of penta-graphene (PG) and SnS2 monolayers, along with their heterostructures (PG/SnS2), using Density Functional Theory (DFT). Structural analysis confirms that the PG/SnS2 heterostructure exhibits enhanced stability, efficient charge separation, and suitable band alignment. Optimized lattice parameters (3.66 & Aring; for PG and 3.88 & Aring; for SnS2) closely matched literature values, while ab initio molecular dynamics (AIMD) confirmed thermodynamic stability at 300 K. The heterostructure's band gap of 2.75 eV (HSE method) supports visible light absorption, and the band edge positions enable hydrogen and oxygen evolution reactions across pH 0 to 6. Optical analysis reveals significant visible-light absorption with an optical band gap of 1.43 eV. Additionally, this study identifies a Z-scheme charge transfer mechanism in the PG/SnS2 heterostructure, facilitated by an internal built-in electric field that drives directional charge migration, effectively enhancing electron-hole separation and suppressing recombination losses. This Z-scheme mechanism optimizes redox reactions, making PG/SnS2 a highly efficient photocatalyst for solar-driven hydrogen production. Furthermore, the effect of water solvent is investigated, and it reveals that this heterostructure is stable under water solvent, having suitable band edges for the photocatalytic water splitting. These findings highlight the PG/SnS2 heterostructure as a promising candidate for sustainable hydrogen generation, offering a new perspective for the design of next-generation 2D photocatalytic materials.
Serum Progesterone Variability on Embryo Transfer Day in Hormone Replacement Therapy Cycles Using Intramuscular Injections During Frozen Embryo Transfers
(Springer/plenum Publishers, 2025) Boynukalin, Fazilet Kubra; Tohma, Yusuf Aytac; Demir, Berfu; Gultomruk, Meral; Polyzos, Nikolaos P.; Bahceci, Mustafa; Bozda, Gurkan; 01. Atılım University
Purpose To assess the intra-individual variability of serum progesterone (P) levels on embryo transfer (ET) day, when the same dose of intramuscular progesterone (IM-P) was used in two consecutive hormone replacement therapy (HRT) frozen embryo transfer (FET) cycles. Methods A total of 75 patients undergoing two consecutive HRT-FET cycles in one year performed at Bahceci Ankara IVF Center between November 2019 and February 2022 were retrospectively analyzed. Serum P levels were measured at the 117th-119th hours of support by a single laboratory. The two measurements of P levels performed on the day of the first and the second FET were compared to evaluate the intra-individual variability of serum P levels. Results Comparisons between the 1st and 2nd FET cycles revealed statistically significant intra-individual variation, with an average difference of -2.47 ng/mL (95% CI: -4.65 to -0.29, p = 0.027) between the two consecutive measurements. To assess their consistency, the limit of agreement was also tested with the Bland-Altman method, in which the mean difference (+ 1.96 x SD and -1.96 x SD) was -2.47 (16.1 and -21.1). Based on a previous study, the frequency of low P levels, as expressed by being > 20.6 ng/mL on ET day, was similar between the 1st and 2nd FET cycles (14.7% vs. 9.3%, p = 0.31). Notably, most patients had improved P levels in the second cycle if initially low, while decreases were rare among those with initially higher levels. Conclusion Serum P levels may vary within the same individual across FET cycles despite the use of the same dosage of IM-P. Increasing maternal age, high body mass index, and fluctuating estradiol levels on the day of ET were identified as risk factors contributing to this variability.
Is Green Servant Leadership a Stronger Predictor of Green Work Engagement and Task-Related Proactive Behaviour Compared to Green Transformational Leadership
(Routledge Journals, Taylor & Francis Ltd, 2025) Yorulmaz, Ali Cenk; Uner, M. Mithat; Rescalvo-Martin, Elisa; Karatepe, Tuna; Saydam, Mehmet Bahri; Karatepe, Osman M.; Business; 05. School of Business; 01. Atılım University
The pertinent literature is devoid of research regarding the effects of green servant leadership (GSL) and green transformational leadership (GTL) simultaneously on green work engagement (GWE) and task-related pro-environmental behaviour (TPEB) and GWE as a mediator in the previously discussed associations. Therefore, drawing from social exchange and job demands-resources theories, our paper develops and tests a research model that investigates the interrelationships of GSL, GTL, GWE, and TPEB. Data were gathered from hotel employees in Ankara, T & uuml;rkiye. The hypotheses were tested using partial least squares structural equation modelling. The results suggest that the positive influence of GSL on GWE is stronger than the positive influence of GTL on GWE. As expected, GWE mediates the effects of GSL and GTL on TPEB. More importantly, the indirect positive influence of GSL on TPEB via GWE is stronger than the indirect positive influence of GTL.
Physical and Mental Effects of Different Radical Prostatectomy Techniques on Urologic Surgeons
(PeerJ Inc, 2025) Olcucu, Mahmut T.; Bolat, Mustafa S.; Yildirim, Kadir; Ozgok, Yasar; Tokas, Theodoros; Gozen, Ali; 01. Atılım University
Objective In this web-based international survey study, we aimed to show an association between physical exhaustion and patient, relatives, and employer-related mental stress for surgeons performing open radical prostatectomy (ORP), laparoscopic radical prostatectomy (LRP), and robot-assisted laparoscopic prostatectomy (RALP). Additionally, we also aimed to compare the outcomes of three approaches. Methods We sent a ten-question survey to the urologists performing ORP, LRP, and RALP via e-mail and social media. Only fully completed surveys were included in the study analysis. We asked questions about age, the preferred surgical approach for radical prostatectomy, frequency of weekly exercise, and their possible associations with physical exhaustion and musculoskeletal complaints. Results A total of 160 urologists completed the survey. The RALP group showed a lower physical exhaustion rate and increased eye strain (p < 0.001) and p = 0.002, respectively). Although walking was the most preferred sports activity, no correlation was found between regular sport or exercise and musculoskeletal complaints (p > 0.05). Conclusion Compared to ORP and LRP, physical exhaustion was lower in the RALP technique. Although the number of participants was limited, regular exercise weakly improved physical exhaustion and musculoskeletal complaints. We believe that regular sports activities by urologists dealing with LRP and RALP will help relieve physical discomfort.
Citation - Scopus: 1
A Review on Membranes for Anion Exchange Membrane Water Electrolyzers
(Pergamon-Elsevier Science Ltd, 2026) Altinisik, Hasan; Celebi, Ceren; Ozden, Adnan; Devrim, Yilser; Colpan, C. Ozgur; Energy Systems Engineering; 06. School Of Engineering; 01. Atılım University
Anion exchange membrane water electrolyzers (AEMWEs) - using water and renewable electricity as the input - provide a sustainable pathway to hydrogen production. AEMWEs perform the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER) with modest overpotentials at practical current densities (>1 A cm(-2)). The recent catalysis, component, and system-level breakthroughs have enabled significant improvements in current densities and energetic efficiencies. The challenge, however, is to maintain these impressive activities and efficiencies through long-term operation at scale. High-performance, efficient, stable, and economically viable AEMWEs require high-performance, low-cost, and scalable anion exchange membranes (AEMs). This Review provides an overview of physical, chemical, and transport properties of commercial and non-commercial AEMs. The article discusses the operating principles, structures, characteristics, strengths, and weaknesses of conventional and emerging AEMs, along with their performance and stability implications in AEMWEs. The article highlights the characteristics that have intricate implications on performance, stability, and cost. It discusses recent advances and best practices to combine high-performance, efficiency, stability, and low-cost in a single AEM structure. The Review highlights the trade-offs between AEM characteristics, with an overview of emerging approaches that would overcome performance, stability, and cost challenges. The Review concludes by highlighting the research gaps and providing research directions with the potential to take the technology a step closer to wide-scale deployment.
Potential Role of SGLT-2 Inhibitors in Improving Allograft Function and Reducing Rejection in Kidney Transplantation
(Wiley, 2025) Demir, Mehmet Emin; Helvaci, Ozant; Yildirim, Tolga; Merhametsiz, Ozgur; Sezer, Siren; 01. Atılım University
Sodium-glucose cotransporter-2 inhibitors (SGLT-2i) have demonstrated renoprotective and cardioprotective benefits beyond their antiglycemic effects. Their potential utility in kidney transplant recipients (KTRs) for preserving graft function and reducing rejection risk is currently under active investigation. Preliminary studies indicate that SGLT-2i therapy stabilizes estimated glomerular filtration rate (eGFR), decreases glomerular hyperfiltration, and improves metabolic outcomes in KTRs. Emerging clinical evidence also suggests that SGLT-2i may be associated with reduced rates of acute rejection, although direct immunosuppressive actions remain unclear. Experimental findings further suggest that SGLT-2i modulates gene regulation pathways involved in inflammation, oxidative stress, and fibrosis, contributing to improved allograft outcomes. Current safety data in KTRs are reassuring, without significant increases in urinary tract infections or adverse graft events. Nevertheless, long-term prospective studies specific to transplant populations are lacking. This review summarizes available evidence regarding the mechanisms of action, clinical efficacy, and safety profile of SGLT-2i in kidney transplantation, emphasizing their metabolic, hemodynamic, inflammatory, and immunomodulatory effects.
Investigations on the Effect of Secondary Treatments on Ti48Al2Cr2Nb Alloy Manufactured by Electron Beam Powder Bed Fusion Method
(Elsevier Sci Ltd, 2025) Bilgin, Guney Mert; Ozer, Seren; Davut, Kemal; Esen, Ziya; Dericioglu, Arcan F.; Metallurgical and Materials Engineering; Department of Metallurgical and Materials Engineering; 15. Graduate School of Natural and Applied Sciences; 06. School Of Engineering; 01. Atılım University
As-built Ti48Al2Cr2Nb alloy samples produced by electron beam powder bed fusion (PBF-EB) exhibited notable brittleness. The low ductility was attributed to coarse gamma bands aligned perpendicular to the building and tensile direction. Additionally, variations in aluminum content and hardness between the coarse colonies and fine gamma/alpha(2) lamellae contribute to this phenomenon. Electron backscattered diffraction (EBSD) studies revealed a higher amount of dislocation density and inherent strain after PBF-EB manufacturing. Hence, usage of Ti48Al2Cr2Nb alloy in the as-built condition in aviation applications with high loads and demanding environments is not found to be viable. To eliminate these negative aspects and make PBF-EB produced Ti48Al2Cr2Nb alloy available for demanding applications, two distinct post-processing heat treatments; namely, hot isostatic pressing (HIP) and annealing heat treatment (HT) were employed at 1200 degrees C. A comprehensive characterization covering microstructure analysis, EBSD, fracture surface examination, as well as room and high-temperature tensile tests allowed determination of the effect of post-processes. HIPing altered the banded structure observed in the as-built samples by increasing the amount of alpha(2) phase and grain size. On the other hand, HT made the banded structure more pronounced without significantly increasing the amount of alpha(2) phase. HT also strengthened the <001> texture, while HIPing introduced randomization of grains. On the other hand, complete recrystallization is achieved as a result of HT at 1200 degrees C for 2 h, whereas HIPing at the same temperature for 2 h induced only 80.5 % recrystallization. In both post-processes, dislocation density and inherent strain were reduced. Room temperature and high-temperature tensile tests demonstrated that both HIPing and HT eliminated the extreme brittleness of the as-built samples.

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