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Article Citation - WoS: 6Citation - Scopus: 6Sns2 and Ho-Doped Sns2 Thin Films: Synergistic, Dft, Photocatalytic, and Antibacterial Studies(Elsevier Sci Ltd, 2024) Radja, Imane; Khane, Yasmina; Oliveira, Marisa C.; Longo, Elson; Ribeiro, Renan A. P.; Isik, Mehmit; Khan, Mohammad MansoobThis study investigates Ho-doped tin disulfide (Ho-SnS2) thin films prepared via spray coating, focusing on varying Ho doping levels (0 at. %, 2 at. %, and 4 at. %). Structural analysis through XRD and SEM showcased enhanced crystallinity and morphology in Ho-SnS2 films. Raman and XPS studies provided insight into the film's composition and chemical states. The antibacterial properties of the films were investigated using a bacterial growth inhibition assay. The results showed significant antibacterial activity against Gram-positive and Gram-negative bacteria, highlighting the potential applications of Ho-SnS2 thin films in antibacterial coatings. Ho-SnS2 films exhibited superior photocatalytic activity and antibacterial properties compared to SnS2 films, attributed to efficient charge separation. DFT analysis proposed a mechanism for the antibacterial activity. These findings highlight the efficacy of the spray coating technique in producing Ho-SnS2 films and the potential of Ho-SnS2 films for diverse applications like photocatalysis and antibacterial coatings.Article Citation - WoS: 8Citation - Scopus: 10Computing Reliability Indices of a Wind Power System Via Markov Chain Modelling of Wind Speed(Sage Publications Ltd, 2024) Eryilmaz, Serkan; Bulanik, Irem; Devrim, YilserStatistical modelling of wind speed is of great importance in the evaluation of wind farm performance and power production. Various models have been proposed in the literature depending on the corresponding time scale. For hourly observed wind speed data, the dependence among successive wind speed values is inevitable. Such a dependence has been well modelled by Markov chains. In this paper, the use of Markov chains for modelling wind speed data is discussed in the context of the previously proposed likelihood ratio test. The main steps for Markov chain based modelling methodology of wind speed are presented and the limiting distribution of the Markov chain is utilized to compute wind speed probabilities. The computational formulas for reliability indices of a wind farm consisting of a specified number of wind turbines are presented through the limiting distribution of a Markov chain. A case study that is based on real data set is also presented.Article Protective Role of Bromelain’s Antioxidant and Anti-Inflammatory Effects in Experimental Lower Limb Ischemia-Reperfusion Injury(Nature Portfolio, 2025) Sezen, Saban Cem; Demirtas, Huseyin; Yildirim, Alperen Kutay; Ozer, Abdullah; Dursun, Ali Dogan; Kucuk, Aysegul; Arslan, Mustafa; Ozalp, Veli Cengiz; Kucuk, Işın GunesIschemia-reperfusion (IR) injury is a multifaceted pathological process characterized by excessive oxidative stress and inflammatory responses upon restoration of blood flow. Bromelain, a proteolytic enzyme complex derived from pineapple, exhibits robust antioxidant and anti-inflammatory activities. This study aimed to evaluate the protective effects and underlying mechanisms of bromelain on oxidative stress and inflammation in an experimental rat model of lower limb ischemia-reperfusion injury. Twenty-four male Wistar Albino rats were randomly allocated into four groups: Sham-operated control (SHAM), Bromelain-only (BR), Ischemia-Reperfusion (IR), and Ischemia-Reperfusion with Bromelain treatment (IR + BR). Bromelain (40 mg/kg) was administered intraperitoneally before ischemia induction. The IR model involved 45 min of infrarenal abdominal aorta occlusion followed by 120 min of reperfusion. Oxidative biomarkers (total antioxidant status [TAS], total oxidant status [TOS], oxidative stress index [OSI]) and histopathological parameters (muscle atrophy, degeneration, leukocyte infiltration, internalization of nuclei, fragmentation, and hyalinization) were analyzed. Significant increases in muscle degeneration, leukocyte infiltration, nuclear internalization, fragmentation, and elevated oxidative stress biomarkers (increased TOS and OSI, decreased TAS) were observed in the IR group compared to controls. Bromelain treatment (IR + BR) significantly ameliorated these effects, reducing muscle tissue damage, inflammation, and oxidative imbalance compared to the untreated IR group. Bromelain effectively mitigates lower limb ischemia-reperfusion injury by reducing oxidative stress, restoring antioxidant capacity, and suppressing inflammatory responses. These protective effects suggest that bromelain holds potential as a therapeutic agent for managing oxidative and inflammatory damages associated with IR conditions, warranting further clinical investigation.Article Citation - WoS: 2Citation - Scopus: 2Biosorption of Reactive Dyes by Novel Bacterium Leclercia Adecarboxylata: Complete Removal of Reactive Black 5 and Molecular Insights Into the Adsorption Mechanism(Wiley, 2025) Sen, Seda; Korkmaz, Filiz; Kilic, Nur KocberberLeclercia adecarboxylata isolated from the D & uuml;den Waterfall (Turkey) was utilized as a biosorbent for the removal of Reactive Black 5 (RB5), Setazol Blue BRF-X (BRF-X), Setazol Navy Blue SBG (SNB), and Setazol Turquoise Blue G (STBG). Of the dyes, RB5 was removed with the highest efficiency, 97.4% after 60 min. The effect of parameters such as pH (3-9), initial biosorbent dose (0.1-2.0 g/L), and initial dye concentration (25-1200 mg/L) on the biosorption of RB5 was investigated. Increasing the biosorbent dosage from 0.1 to 2.0 g/L enhanced the RB5 removal from 55.3% to 100% within 10 min. The complete removal (100%) of RB5 was achieved in media with 2.0 g/L biosorbent and 25 mg/L RB5 at pH 3 after 10 min. Additionally, the soluble extracellular polymeric substances (EPS) of L. adecarboxylata were found to consist of proteins, lipids, nucleic acids, and polysaccharides according to Fourier transform infrared spectroscopy (FTIR) analysis. The EPS was found to play a crucial role in dye removal, forming chemical interactions with dye molecules. Zeta potential analysis was used to evaluate the charge distribution on the biosorbent surface (-12.6 +/- 1.1 mV) and its interactions in the biosorption process. Kinetic and isotherm models suggested a complex interaction mechanism between the biomass and the dye. Adsorption isotherm data were analyzed via nine isotherm models. Among them, the Hill model was found to be the best fit for describing the equilibrium adsorption process of the RB5 (R2 = 0.9993). Overall, the applied models elucidated the influence of both physical and chemical interactions on the mechanism. Kinetic studies revealed that the adsorption of RB5 fit a pseudo-second-order kinetic model. The unique biochemical composition of the indigenous L. adecarboxylata biosorbent provided a high affinity for RB5, offering a sustainable, rapid, and economical solution for the treatment of dye-polluted water.Article Citation - WoS: 3Citation - Scopus: 3Development and Validation of a Sensitive Assay for the Quantification of Arachidonoylcyclopropylamide (acpa) in Cell Culture by Lc-ms/Ms(Springer int Publ Ag, 2023) Boyacioglu, Ozge; Recber, Tuba; Kir, Sedef; Korkusuz, Petek; Nemutlu, EmirhanSynthetic and natural cannabinoid derivatives are highly investigated as drug candidates due to their antinociceptive, antiepileptic and anticancer potential. Arachidonoylcyclopropylamide (ACPA) is a synthetic cannabinoid with antiproliferative and apoptotic effects on non-small cell lung cancer and pancreatic and endometrial carcinoma. Thus, ACPA has a great potential for being used as an anticancer drug for epithelial cancers. Therefore, determining the levels of ACPA in biological fluids, cells, tissues and pharmaceutical dosage forms is crucial in monitoring the effects of various pharmacological, physiological and pathological stimuli on biological systems. However, the challenge in the quantification of ACPA is its short half-life and lack of UV signal. Therefore, we developed a liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for sensitive and selective quantification of ACPA in cell culture medium and intracellular matrix. Multiple reaction monitoring in the positive ionization mode was used for detection with 344 -> 203 m/z transitions. The separation of ACPA was performed on C18 column (50 x 3.0 mm, 2.1 mu m) with the mobile phase run in the gradient mode with 0.1% formic acid (FA) in water and 0.1% FA in acetonitrile at a flow rate of 0.3 ml/min. The assay was linear in the concentration range of 1.8-1000 ng/mL (r = 0.999). The validation studies revealed that the method was linear, sensitive, accurate, precise, selective, repeatable, robust and rugged. Finally, the developed method was applied to quantify ACPA in cell culture medium and intracellular matrix.Article Citation - WoS: 2Citation - Scopus: 4Mobile Application Software Requirements Specification From Consumption Values(Mdpi, 2023) Derawi, Mohammad; Dalveren, Gonca Gokce Menekse; Cagiltay, Nergiz ErcilIn today's society, mobile applications are becoming more popular and providing several advantages. However, users will resist using a product regardless of how well-tested or solid it is if the wrong requirements are implemented. Understanding the factors that influence the purchase of mobile applications can provide useful information for mobile application design and development. Hence, the purpose of this research is to better understand the impact of consumption values on customers in order to identify the software requirements for a mobile application. This study analyzes the possible behavioral changes of similar groups of university students in a five-year period. For this purpose, a questionnaire is administered to engineering faculty students in 2017 (46 females and 66 males) and 2021 (45 females and 90 males) to better understand customer behavioral changes. The findings highlight the significance of conditional value in customer behavior when purchasing mobile applications. Even though the other consumption values were found to have a negligible effect, there is some evidence indicating that the impact of consumption values on different target customer groups may vary considering their gender and familiarity with apps. Further research needs to be conducted to better understand the possible impact of age, cultural differences, education levels, and special considerations such as visually impaired people. Therefore, this study encourages mobile application designers and developers to raise awareness for the effect of consumption values such as conditional value on their customers' mobile application purchasing behaviors. The possible impact of the consumption values needs to be deeply understood, specifically for the target customer groups, and it should be considered in the software requirements specification (SRS), which is one of the important principles that allow software under consideration for development to function. As a result, a better understanding of consumption values will help developers design and develop better applications by specifying software requirements and marketing strategies.Article Citation - WoS: 2Citation - Scopus: 2Thermoluminescence Dose Response and Kinetic Parameters of Gd-Doped Zno Nanoparticles(Iop Publishing Ltd, 2024) Isik, M.; Yildirim, T.; Guner, M.; Gasanly, N. M.This study investigates the thermoluminescence (TL) properties of undoped and gadolinium (Gd)-doped zinc oxide (ZnO) nanoparticles synthesized via sol-gel method. The crystal structure of both synthesized nanoparticles was determined as hexagonal from x-ray diffraction pattern. The TL curve of undoped ZnO nanoparticles reveals two distinct peaks at 400.5 and 479.2 K, each associated with trap centers featuring activation energies of 0.84 and 1.05 eV. TL curve of the Gd:ZnO introduced three peaks associated with trap centers at 1.10, 1.18, and 1.25 eV. Notably, the absence of the 0.84 eV trap center in Gd-doped ZnO implies a modification in the defect structure. Considering the effect of Gd-doping on the band structure and potential minor errors in the analysis results, it was stated that the traps at 1.05 and 1.10 eV levels belonged to the same defect center. Dose-dependent investigations for undoped and Gd-doped ZnO nanoparticles reveal linear behaviors in the TL response, highlighting their potential for dosimetric applications. Photoluminescence spectra of both compounds exhibited emission peaks around 455 and 577 nm, which were associated with native defect centers.Article Citation - WoS: 1Citation - Scopus: 1Cold War Aviation: American Technology Transfer and the Construction of Turkey's First International Civilian Airport in Yeşilköy, Istanbul, 1944-1953(Cambridge Univ Press, 2024) Tunc, Tanfer Emin; Tunc, GokhanWith the economic and political support of the United States, in July 1947, Turkey signed contracts withthe Westinghouse Electric International Company and J.G. White Engineering Corporation to constructits first international civilian airport, Istanbul'sYe & scedil;ilk & ouml;y Airport. As this article will argue, the buildingof Ye & scedil;ilk & ouml;y (1949-53), through a partnership with two American engineering firms, is essentially anearly Cold War narrative of transnational exchange involving the multidirectional flow of technicalknowledge, expertise and resources between the United States and Turkey; the circulation of geopol-itically significant (and frequently competing) military, civilian and government actors; and thelocal and global implications of these transmissions. Yet the Ye & scedil;ilk & ouml;y construction narrative also illus-trates how post-war technology transfer was a highly political process of constant adaptation, modifi-cation and negotiation. Fraught with unforeseen friction and thorny challenges, Ye & scedil;ilk & ouml;y exemplifiesthe complicated American Cold War strategy of creating and maintaining alliances through engineeringknowledge, personnel and practices, often with unintended consequences. Moreover, as a case study,Ye & scedil;ilk & ouml;y opens a new window into the cautious science diplomacy that occurred along the IronCurtain, while filling a notable historiographic gap with respect to aviation in early Cold War Turkey.Article Moocs and Economic Disadvantage: a Path Analysis of 3.5 Million Mitx Learners(Routledge Journals, Taylor & Francis Ltd, 2025) Cagiltay, Nergiz Ercil; Toker, Sacip; Cagiltay, KursatMassive Online Open Courses (MOOCs) are offered by universities and companies to provide quality education to anyone, anyplace and at any time. The impact of economic disadvantage on these courses has not been fully explored despite several studies. This study aimed to investigate the impact of country's income level on the success of 3,523,692 learners from 204 countries enrolled in 174 MITx MOOCs. The countries were classified as low- and lower-middle-income (L&LM) or high- and upper-middle-income (H&UM). A structural equation modelling with multigroup analysis conducted. The findings revealed that learners in the L&LM group performed better academically. Completion rates were 66% for L&LM and 25% for H&UM, and certification rates were 95% for L&LM and 99% for H&UM. This shows that L&LM learners may be more motivated because they believe MOOCs might help their careers. These results are essential for creating MOOCs that fit diverse learner demographics.Article Citation - WoS: 22Citation - Scopus: 26Effect of Solution Heat Treatment on the Microstructure and Crystallographic Texture of In939 Fabricated by Powder Bed Fusion-Laser Beam(Elsevier, 2023) Dogu, Merve Nur; Ozer, Seren; Yalcin, Mustafa Alp; Davut, Kemal; Bilgin, Guney Mert; Obeidi, Muhannad Ahmed; Brabazon, DermotThe effect of various solution heat treatment temperatures (i.e., 1120, 1160, 1200 and 1240 & DEG;C) on the microstructure, grain morphology and crystallographic texture of IN939 fabricated by powder bed fusion-laser beam (PBF-LB) was investigated. Microstructural analyses showed that the high-temperature gradient and rapid solidification of the PBF-LB processing caused different resulting microstructures compared to conventionally pro-duced counterparts. The melt pool morphologies and laser scanning paths were examined in the as-fabricated samples in the XZ-and XY-planes, respectively. After the application of solution heat treatment at 1120 & DEG;C, the as-fabricated PBF-LB initial microstructure was still apparent. For solution heat treatments of 1200 & DEG;C and above, the melt pool and scanning path morphologies disappeared and converted into a mixture of columnar grains in the XZ-plane and equiaxed grains in the XY-plane. On the other hand, large equiaxed grains were observed when the samples were solutionized at 1240 & DEG;C. Additionally, g' phase precipitated within the matrix after all solution heat treatment conditions, which led to increase in the microhardness values. According to electron backscatter diffraction (EBSD) analyses, both as-fabricated and solution heat-treated samples had intense texture with {001} plane normal parallel to the building direction. The first recrystallized grains began to appear when the samples were subjected to the solution heat treatment at 1160 & DEG;C and the fraction of the recrystallized grains increased with increasing temperature, as supported by kernel average misorientation (KAM) and grain spread orientation (GOS) analyses.& COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).