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Article Citation - WoS: 1TRIPLE FIXED POINT THEOREMS FOR WEAK (ψ-φ)-CONTRACTIONS(Eudoxus Press, Llc, 2013) Karapinar, Erdal; Sadarangani, KishinThe notion of coupled fixed point is introduced in by Bhaskar and Lakshmikantham in [2]. Very recently, the concept of the tripled fixed point is introduced by Berinde and Borcut [1]. They also proved some triple fixed point theorems. In this manuscript, by using the weak (psi - phi)-contraction, the results of Berinde and Borcut [1] are generalized.Article Citation - WoS: 6Synthesis and Biological Study of Novel Indole-3 Derivatives as Src Kinase and Glutathione S-Transferase Inhibitors(Bentham Science Publ Ltd, 2013) Kurt, Z. Kilic; Aydin, D.; Isgor, Y. G.; Isgor, B. S.; Olgen, S.The aim of this study is to design and synthesize novel dual inhibitors of Src protein tyrosine kinase (PTK) and Glutathione S-transferases (GSTs), as a potential drug lead with therapeutic efficacy on cancer and immune disorders. The biological activity profiling of small molecule inhibitors via miniaturized biochemical techniques compatible with medium throughput screening and focused screening methodologies were performed. To determining the effects of small molecule inhibitors on Src kinase and Phase II detoxification enzyme GST isozymes in liver homogenates used to verify their roles in drug resistance mechanism for cancer chemotherapeutics. In this study, 14 indole-3-imine-2-on and N-benzyl indole-3-imine-2-on derivatives were synthesized for dual activities against Src and GST. The chemical structures and purities of compounds were verified by IR, H-1 NMR, MASS spectroscopy, and elemental analysis. The compounds 2, 3 and 9 are found slightly active against both enzyme Src and GST.Article On a Boundary Value Problem for a Class of Second-Order Complex Partial Differential Equations(Univ Simon Bolivar, 2023) Aksoy, Umit; Celebi, Ahmet OkayIn this article, a boundary value problem for a second-order complex partial differential equation whose main part is the Laplacian, is introduced and its solvability is discussed by reduction of the problem into the Schwarz problem for a first-order equation. The condition for solvability is presented and an estimate for the unique solution is provided.Article Citation - WoS: 4Citation - Scopus: 6A Test Bench To Study Bioinspired Control for Robot Walking(Romanian Soc Control Tech informatics, 2011) Arikan, Kutluk B.; Irfanoglu, Bulent; Department of Mechatronics EngineeringTest bench to study robot walking within the predicted structures of biological control systems is discussed. Physical system is briefly presented with components. Kinematic model and evolutionary way of gait generation for the leg structure in test bench is discussed. Different forms of gaits can be found by genetic optimization using patterns formed by central pattern generators.Article Citation - WoS: 3Citation - Scopus: 3How Do Implant Threads and Diameters Affect the All-On Success? a 3d Finite Element Analysis Study(IOS Press BV, 2022) Zor,Z.F.; Klllnç,Y.; Erkmen,E.; Kurt,A.; Kilinc, YelizBACKGROUND: The effect of different thread designs and diameters on the all-on-four concept is unclear. OBJECTIVE: The aim of the study was to clarify the differences in stress distribution of dental implants with various thread designs and diameters based on the all-on-four concept with three dimensional (3D) finite element analysis (FEA). METHODS: A 3D model of a totally edentulous mandible was used to perform the FEA. Four different models (M1, M2, M3, and M4) including 3.5 and 4.3 mm diameter dental implants with active and passive threaded designs were generated. The dental implants were positioned according to the all-on-four concept. The Von Mises stresses on dental implants and maximum and minimum principal stresses (Pmax and Pmin) on bony structures were calculated under vertical, oblique and horizontal loads. RESULTS: For Von Mises stresses, the highest stress values were detected on the distal implants for all models. Distal implants had also the highest stress values for vertical loading. The Von Mises stresses were found to be concentrated around the implant's neck. In all models the highest Pmax and Pmin stresses occurred in the bone surrounding the distal implant. It was noted that the active threaded implants showed the highest Pmax and Pmin stress values. CONCLUSION: The implant thread design and diameter might have a strong influence on the stress values in the all-on-four concept. © 2022 - IOS Press. All rights reserved.Article The Effect of Endurance-Based Sports on Athlete Success and Psychological Well-Being(Campus Educa Sports Sl, 2025) Ozpinar, Saliha; Yucel, Ali Serdar; Korkmaz, Murat; Oztas, Dilek; Kuyucu, Mihalis Michael; Aras, Goksen; Yüce, Ali SerdarThe aim of this study is to examine the effects of psychological resilience on sport success and mental health. The relationships between commitment, control and challenge, which are sub-dimensions of psychological resilience, and sport success and psychological wellbeing were evaluated and discussed in detail. Today, the problems arising due to the increasing competitive environment and stress factors have made it more important for athletes to be psychologically strong. Although the relationship between psychological resilience and sport success has been previously examined in the literature, studies evaluating the individual effects of the sub-dimensions of resilience in a large sample group are quite limited. This study aims to overcome this deficiency and make an up-to-date contribution to the subject. A total of 684 students (72 percent male, 28 percent female) studying at the Faculties of Sport Sciences of 16 universities in Istanbul, Ankara, Izmir, Bursa and Antalya participated in the study. Participants completed the Resilience Scale and Mental Health Inventory, and their sporting achievements were evaluated by their coaches using the Sport Achievement Scale. Data were collected via Google Forms (R) and analysed using SPSS 22.0 software with correlation, regression and Granger causality tests. The findings revealed that all resilience sub-dimensions showed positive and significant relationships with sport achievement ( R-2=0.93) and psychological well-being (R-2=0.68). Especially control and challenge factors had the strongest effects. As a result of the research, commitment, control and challenge, which are the sub-dimensions of psychological resilience, significantly affect both success levels and psychological well-being of athletes. Therefore, resilience development programmes for athletes should focus on these areas.Article 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, SelmaIntroduction: 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.Article Citation - WoS: 8Citation - Scopus: 8Evolution of Aluminium Melt Quality of A356 After Several Recycling(Polska Akad Nauk, Polish Acad Sciences, 2020) Gursoy, O.; Erzi, E.; Tur, K.; Dispinar, D.Recyclability is one of the great features of aluminium and its alloys. However, it has been typically considered that the secondary aluminium quality is low and bad. This is only because aluminium is so sensitive to turbulence. Uncontrolled transfer and handling of the liquid aluminium results in formation of double oxide defects known as bifilms. Bifilms are detrimental defects. They form porosity and deteriorate the properties. The detection and quantification of bifilms in liquid aluminium can be carried out by bifilm index measured in millimetres as an indication of melt cleanliness using Reduced Pressure Test (RPT). In this work, recycling efficiency and quality change of A356 alloy with various Ti additions have been investigated. The charge was recycled three times and change in bifilm index and bifilm number was evaluated. It was found that when high amount of Ti grain refiner was added, the melt quality was increased due to sedimentation of bifilms with Ti. When low amount of Ti is added, the melt quality was degraded.Article Investigation of Tetanus Seropositivity Levels in Adult Patients with Rabies Risk Exposure Admitted To a Hospital in Ankara(J Infection Developing Countries, 2025) Gurkaynak, Pinar; Demircan, Serife A.; Tulek, Necla; Kinikli, Sami; Erdinc, Fatma S.; Tuncer, GunayIntroduction: This study aimed to assess tetanus seropositivity levels among adult patients admitted to a tertiary care hospital following rabies risk exposure, and to explore potential factors influencing their immunological status. Methodology: This cross-sectional descriptive epidemiological study included 182 adult individuals (68 females and 114 males) who presented to the hospital following rabies risk exposure. The demographic data was collected during a face-to-face interview, and the tetanus antibody concentrations were assessed using a micro-enzyme-linked immunosorbent assay (ELISA) kit. Serum antibody levels of >= 0.1 IU/mL were defined as "seropositive", while values below this threshold were considered "seronegative". Results: Seropositivity was identified in 81.9% of the patients. There was a significant decline in antibody levels with age (p < 0.001). The Spearman correlation analysis showed a moderately significant negative correlation between age and antibody titers (r = - 0.404, p < 0.001). In addition, there were significantly higher tetanus antibody levels in patients from urban areas, those vaccinated during pregnancy, and those vaccinated within the past 10 years (p = 0.025, 0.036, and 0.013, respectively). Conclusions: Overall, the results highlight a reduction in tetanus antibody levels with age, emphasizing the importance of receiving a booster dose every 10 years. In addition, rabies risk exposure, particularly in older adults, presents a valuable opportunity to administer tetanus vaccination.Conference Object Citation - WoS: 11Modeling Flexforming (fluid Cell Forming) Process With Finite Element Method(Trans Tech Publications Ltd, 2007) Hatipoglu, H. Ali; Polat, Naki; Koeksal, Arif; Tekkaya, A. ErmanIn this paper, the flexforming process is modeled by finite element method in order to investigate the operation window of the problem. Various models are established using explicit approach for the forming operation and implicit approach for the unloading one. In all analyses the rubber diaphragm has been modeled revealing that the modeling of this diaphragm is essential. Usine the material Aluminum 2024 T3 alclad sheet alloy, three basic experiments are conducted: Bending of a straight flange specimen, bending of a contoured flange specimen and bulging of a circular specimen. By these experiments tile effects of blank thickness, die bend radius, flange length and orientation of the rolling direction of the part have been investigated. Experimental results are compared with finite element results to verify the computational models.
