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Article Citation - WoS: 2Citation - Scopus: 4State-Based Conceptual Design in Mechatronics Via Petri Nets: a Case Study for an Educational Robot(Romanian Soc Control Tech informatics, 2011) Erden, Zuhal; Mechatronics EngineeringUse of state-based models to represent artifact behaviors at conceptual design is a challenging area for design research. Conceptual design of mechatronic systems needs a multi-domain approach in which the "logical behavior" of a mechatronic design artifact is described without any physical realization. This paper presents a case study on state-based representation for the intended behavior of a non-existent robot at early conceptual level. The behavior is defined through a demonstrative scenario and represented as states and state transitions independent of any physical embodiment. Discrete Event System Specification (DEVS) and Petri Net formalism are used for the model. This representational model is first step towards the development of a virtual prototype for the logical behavior of robot design.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 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, GoksenThe 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.Article Citation - WoS: 23Citation - Scopus: 25Comparison of Cellular Proliferation on Dense and Porous Pcl Scaffolds(Ios Press, 2008) Sasmazel, Hilal Tuerkoglu; Gumusderelioglu, Menemse; Gurpinar, Aylin; Onur, Mehmet AliIn this contribution, PCL (poly-e caprolactone) scaffolds were prepared by solvent-casting/particle-leaching technique in the presence of two pore formers, PEG(4000) or sucrose molecules in different quantities (0, 10, 20, 30, 40, 50, 55 w/w% PEG(4000)/PCL; 10, 20 w/w% Sucrose/ PCL). The surface and bulk properties of the resulting scaffolds were studied by SEM, DSC and FTIR. SEM photographs showed that, macroporosity was obtained in the PCL structures prepared with sucrose crystals while microporous structure was obtained in the presence of PEG(4000) molecules. Average pore diameters calculated from SEM photographs were 40.1 and 191.2 mu m for 40% PEG(4000)/PCL and 10% Sucrose/PCL scaffolds, respectively. The DSC and FTIR results confirmed that there is no any interaction between pore formers and PCL during structural formation, and both pore formers, PEG(4000) and sucrose, remained independently in the scaffolds. L929 mouse fibroblast cells were seeded onto PCL structures and maintained during 7 days to evaluate cell proliferation. Cell culture results showed that, 10% Sucrose/ PCL scaffold was the most promising substrate for L929 cell growth due to 3-D architecture and macroporous structure of the scaffold.Article A Preliminary Study Evaluating Trans-Fat Content of Pastries in Socioeconomically Disadvantaged Communities of Istanbul(Marmara Univ, Fac Medicine, 2021) Ay, Pinar; Qutranji, Lubna; Cetin, Okan; Rezai, Esmatullah; Fayazi, Rohullah; Gezer, Tanzer; Dagli, ElifObjective: Trans-fatty acids (TFAs) pose several risks to human health. World Health Organization recommends the elimination of trans-fat consumption through limiting their use as less than 2g/100g fat. In line with this recommendation, Turkey recently passed a new regulation securing the content of TFAs as less than 2g/100g fat in industrially produced foods. The objective of this study was to determine the proportion of high TFA (>2 g/100g fat) in pastries among socioeconomically disadvantaged communities of Istanbul before the regulation was put into force. Materials and Methods: Eight socioeconomically disadvantaged districts were chosen from Istanbul and from each district three neighborhoods with the lowest land values were identified. Pastry samples were collected from 72 shops. TFA content was analyzed at Scientific and Technological Research Council of Turkey (TUBITAK) Marmara Research Center by the ISO 12966-2:2011 method. p<0.05 was set as the level of statistical significance. Results: The median (25th-75th percentile) value of TFAs was 0.19g/100g (0.048/1008 - 0.30g/100g). None of the samples exceeded the level of 2g/100g. There was no difference in TFA content between the districts (p>0.05). Conclusion: Our findings indicate that Turkey could easily comply with the legislative limit of 2%. Still, the compliance should continuously be evaluated in diverse populations of the country.
