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Article Citation - WoS: 16Citation - Scopus: 17Subacute Thyroiditis Related To Sars-Cov Vaccine and Covid-19 (thyrovac Study): a Multicenter Nationwide Study(Endocrine Soc, 2023) Batman, Adnan; Yazici, Dilek; Dikbas, Oguz; Agbaht, Kemal; Saygili, Emre Sedar; Demirci, Ibrahim; Sahin, MustafaContext The aims of the study are to compare characteristics of subacute thyroiditis (SAT) related to different etiologies, and to identify predictors of recurrence of SAT and incident hypothyroidism. Methods This nationwide, multicenter, retrospective cohort study included 53 endocrinology centers in Turkey. The study participants were divided into either COVID-19-related SAT (Cov-SAT), SARS-CoV-2 vaccine-related SAT (Vac-SAT), or control SAT (Cont-SAT) groups. Results Of the 811 patients, 258 (31.8%) were included in the Vac-SAT group, 98 (12.1%) in the Cov-SAT group, and 455 (56.1%) in the Cont-SAT group. No difference was found between the groups with regard to laboratory and imaging findings. SAT etiology was not an independent predictor of recurrence or hypothyroidism. In the entire cohort, steroid therapy requirement and younger age were statistically significant predictors for SAT recurrence. C-reactive protein measured during SAT onset, female sex, absence of antithyroid peroxidase (TPO) positivity, and absence of steroid therapy were statistically significant predictors of incident (early) hypothyroidism, irrespective of SAT etiology. On the other hand, probable predictors of established hypothyroidism differed from that of incident hypothyroidism. Conclusion Since there is no difference in terms of follow-up parameters and outcomes, COVID-19- and SARS-CoV-2 vaccine-related SAT can be treated and followed up like classic SATs. Recurrence was determined by younger age and steroid therapy requirement. Steroid therapy independently predicts incident hypothyroidism that may sometimes be transient in overall SAT and is also associated with a lower risk of established hypothyroidism.Article Citation - WoS: 62Citation - Scopus: 69Estimation in Coherent Reliability Systems Through Copulas(Elsevier Sci Ltd, 2011) Eryilmaz, SerkanThe problem of estimating the parameter of a common distribution of components' lifetimes from system's lifetime data is of interest and importance in reliability engineering. The present paper deals with this problem when the common component distribution is exponential with mean it and the lifetimes of components have an exchangeable joint distribution which is constructed by the help of Archimedean copula. In particular we obtain moment estimator of p for Clayton and Ali-Mikhail-Haq copulas. We illustrate the findings of the paper for a special class of coherent systems called consecutive k-within-m-out-of-n:F system. A simulation study is performed to investigate the properties of the moment estimator. The method presented in this paper can be applied to all coherent systems. (C) 2010 Elsevier Ltd. All rights reserved.Article Policy Frameworks Without Practice? Exploring Marine Governance and Climate Integration Challenges in Türkiye(Elsevier Sci Ltd, 2026) Karli, AygunThe marine-climate nexus has emerged as a critical frontier in global environmental governance, yet its integration into national policy frameworks remains uneven. This article examines the case of T & uuml;rkiye, a middleincome country with extensive coastlines and increasing exposure to climate risks, to explore how marine and climate governance interact in practice. Drawing on 22 semi-structured interviews with experts from government, civil society, and academia, the study applies thematic analysis to identify six interrelated challenges: (1) the gap between legal frameworks and implementation, (2) crisis-based governance, (3) institutional fragmentation and coordination deficits, (4) dependence on European Union funding and external alignment, (5) societal indifference and limited marine literacy, and (6) the contested discourse of the blue economy. The findings demonstrate that although T & uuml;rkiye has adopted robust legal instruments and aligned with EU standards, enforcement and institutional integration remain weak. Governance is often reactive, fragmented, and externally driven, with limited societal demand for ambitious reforms. These dynamics reflect broader patterns in global marine-climate governance but are compounded by T & uuml;rkiye's context specific political and institutional constraints. The article argues that bridging the persistent policy-practice gap will require stronger institutional coordination, investments in capacity and literacy, and reframing the blue economy as a vehicle for climate adaptation and mitigation rather than narrow economic growth.Conference Object Citation - WoS: 134Citation - Scopus: 148Polybenzimidazole/Sio2< Hybrid Membranes for High Temperature Proton Exchange Membrane Fuel Cells(Pergamon-elsevier Science Ltd, 2016) Devrim, Yilser; Devrim, Huseyin; Eroglu, InciPolybenzimidazole/Silicon dioxide (PBI/SiO2) hybrid membranes were prepared and characterized as alternative materials for high temperature proton exchange membrane fuel cell (HT-PEMFC). The PBI/SiO2 membranes were cast from a PBI polymer synthesized in the laboratory and contained 5 wt. % SiO2 as inorganic filler. Scanning electron microscopy (SEM) analysis showed that the uniform and homogeneous distribution of SiO2 particles in the hybrid membrane. The existence SiO2 has improved the acid retention and proton conductivity properties. A maximum conductivity of 0.1027 S/cm at 180 degrees C was obtained for the PBI/SiO2 hybrid membrane. Gas diffusion electrodes (GDE) were fabricated by ultrasonic coating technique with 1 mg Pt/cm(2) catalyst loading for both anode and cathode. The membranes were tested in a single HT-PEMFC with a 5 cm(2) active area operating at the temperature range of 140 degrees C-180 degrees C. Single HT-PEMFC tests indicated that PBI/SiO2 hybrid membrane was more stable and also performed better than pristine PBI membrane. Maximum current density was observed for PBI/SiO2 membrane at 165 degrees C and cell voltage of 0.6 V as 0.24 A/cm(2). The results suggested that PBI/SiO2 hybrid membrane is promising electrolytes for HT-PEMFC with improved fuel cell performance. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Article Citation - WoS: 11Citation - Scopus: 11A Standard Benchmarking Suite for Structural Optimization Algorithms: Iscso 2016-2022(Elsevier Science inc, 2023) Azad, Saeid Kazemzadeh; Azad, Saeıd Kazemzadeh; Azad, Sina Kazemzadeh; Azad, Saeıd Kazemzadeh; Department of Civil Engineering; Department of Civil EngineeringBenchmarking is an essential part of developing efficient structural optimization techniques. Despite the advent of numerous metaheuristic techniques for solving truss optimization problems, benchmarking new algorithms is often carried out using a selection of classic test examples which are indeed unchallenging for contemporary sophisticated optimization algorithms. Furthermore, the limited optimization results available in the literature on new test examples are usually not accurately comparable. This is typically due to the lack of infromation about the performance of the investigated algorithms and the inconsistencies between the studies in terms of adopted test examples for benchmarking, optimization problem formulation, maximum number of objective function evaluations and other similar issues. Accordingly, there exists a need for developing new standard test suites composed of easily reproducible challenging test examples with rigorous and comparable performance evaluation results of algorithms on these test suites. To this end, the present work aims to propose a new baseline for benchmarking structural optimization algorithms, using a set of challenging sizing and shape optimization problems of truss structures selected from the international student competition in structural optimization (ISCSO) instances. The most recent six structural optimization examples from the ISCSO are tackled using a representative metaheuristic structural optimization algorithm. The statistical results of all the optimization runs using the proposed benchmarking suite are provided to pave the way for more rigorous benchmarking of structural optimization algorithms.Article Citation - WoS: 22Citation - Scopus: 41Argumentation To Foster Pre-Service Science Teachers' Knowledge, Competency, and Attitude on the Domains of Chemical Literacy of Acids and Bases(Royal Soc Chemistry, 2017) Cigdemoglu, C.; Arslan, H. O.; Cam, A.Argumentative practices have the potential to contribute to scientific literacy. However, these practices are not widely incorporated in science classrooms and so their effect on the domains of literacy is still not revealed. Therefore, this study proposes to reveal the effect of argumentation on the three domains of chemical literacy related to the concepts of acids and bases. The study participants comprised 29 freshman pre-service science teachers' enrolled in a General Chemistry-II course. Argumentation practices were implemented over six weeks. Open-ended contextual chemical literacy items were developed to assess the differences in the chemical literacy domains and the items were administered before and right after the intervention. The responses to the chemical literacy items were scored with a rubric and three scores were calculated: knowledge, competency, and attitudes. Paired sample t-tests were used to compare the mean scores. All the intervention sessions were video recorded, and three of them were analyzed according to three criteria: the presence of arguments, the frequency of arguments, and the levels of the arguments. The findings revealed that the argumentation practices contributed to the pre-service teachers' chemical literacy skills, mostly to their knowledge and competencies when compared to their attitudes. Moreover, distinct differences in the quality of argumentation levels were observed over the six weeks.Article Citation - WoS: 11Citation - Scopus: 11Design and Applications of Al/Inse Hybrid Device(Ieee-inst Electrical Electronics Engineers inc, 2015) Qasrawi, Atef F.; Khanfar, Hazem K.In this paper, a hybrid device made of Ag/BN Schottky barrier and anisotype InSe/BN heterojunction is designed and characterized. The design of the energy band diagram of the device revealed a valance band splitting at the InSe/BN interface and a barrier height at the Ag/BN junction of 3.04 and 6.49 eV, respectively. These parameters which were designed to force current conduction by tunneling were experimentally confirmed by the dark I-V characteristics which revealed an electric field assisted tunneling process. The hybrid device exhibited high/low current switching property at Vs = 2.60 V when forward biased. When the device was exposed to 850-nm lasers light, Vs regularly increased with increasing light power indicating the applicability of these devices as IR photodetectors. In addition, when it was used as capacitor and depleted with signal of frequency of 0.1 GHz and varying amplitude it showed good energy storing property with a quality factor of similar to 200. On the other hand, when the hybrid device was used as microwave resonator it behaves like bandstop filter that blocks signals of various notch frequencies in the range of 1.58-2.30 GHz. The features of the device are promising as they indicate the applicability of the Al/InSe/BN/Ag in communication technology.Article Hagia Sophia's Reconversion: Turkey's De-Europeanization through Lefebvre's Spatial Triad(Routledge Journals, Taylor & Francis Ltd, 2026) Akdemir, Tugba Gurcel; Resuloglu, CilgaHagia Sophia, as a monument of enduring historical and cultural significance, has long stood at the intersection of religious, spatial, and political transformations. Its successive conversions - from basilica to mosque, from museum to mosque again - constitute the layers of its multidimensional character and reflect its symbolic role beyond mere architecture as a palimpsest of meanings. Throughout history, sovereignty over Hagia Sophia has embodied hegemonic power, with its spatial reconfigurations serving political concerns and ideological narratives. This article argues that Turkey's recent de-Europeanization is materially and symbolically manifested in the 2020 reconversion of Hagia Sophia into a mosque. By situating this transformation within Lefebvre's triadic spatial model-perceived space, conceived space, and lived space, the study conceptualizes Hagia Sophia as a paradigmatic site where space, power, and politics intersect, offering an interdisciplinary framework that links the politics of Europeanization with the spatial production of power.Article Citation - WoS: 43Citation - Scopus: 50On the lifetime behavior of a discrete time shock model(Elsevier, 2013) Eryilmaz, SerkanIn this article, we study a shock model in which the shocks occur according to a binomial process, i.e. the interarrival times between successive shocks follow a geometric distribution with mean 1/p. According to the model, the system fails when the time between two consecutive shocks is less than a prespecified level. This is the discrete time version of the so-called delta-shock model which has been previously studied for the continuous case. We obtain the probability mass function and probability generating function of the system's lifetime. We also present an extension of the results to the case where the shock occurrences are dependent in a Markovian fashion. (C) 2012 Elsevier B.V. All rights reserved.Article Citation - WoS: 14Citation - Scopus: 17NEW EDOT CONTAINING POLYMERS: EFFECT OF RING SIZE ON THE BENZIMIDAZOLE ACCEPTOR(Pergamon-elsevier Science Ltd, 2016) Cansu-Ergun, E. G.; Onal, A. M.; Cihaner, A.In this study, three different benzimidazole (BIm) based acceptor groups bearing cyclohexane, cycloheptane and cyclooctane rings at 2-C position of benzimidazole were synthesized and coupled with ethylenedioxythiophene (EDOT) donor units via Stille cross-coupling reaction. The resulting donor acceptor-donor (DAD) type monomers were examined in terms of their electrochemical and optical behaviors. All three monomers exhibited dual absorption bands due to their donor-acceptor pattern and exhibited one irreversible oxidation peak at about 0.80 V. The monomers were electrochemically polymerized via both potentiostatic and potentiodynamic methods and electro-optical properties of obtained conjugated polymer films were investigated in monomer free electrolytic solution. It was found that the polymer films exhibited quasi-reversible redox behavior due to the doping/dedoping process of the polymers, which was accompanied by a reversible electrochromic behavior. Electrochromic investigations showed that all three polymer films showed similar multichromic behaviors: green in the neutral state, gray in the oxidized state, and brick-red in the reduced state. Their band gap (Eg) values were elucidated utilizing spectroelectrochemical data and it was found to be around 1.18 eV. Furthermore, one of the polymer film was utilized for the construction of transmissive type electrochromic device (ECD) with poly(3,4-ethylenedioxythiophene) (PEDOT). (C) 2015 Elsevier Ltd. All rights reserved.
