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Article Citation - WoS: 6Citation - Scopus: 6Excessive Damage Increase in Dual Phase Steels Under High Strain Rates and Temperatures(Sage Publications Ltd, 2021) Cobanoglu, Merve; Ertan, Rasim K.; Simsir, Caner; Efe, MertDamage formation in dual phase steels is a complex process and it may be sensitive to the deformation conditions and mechanisms. In this study, the damage parameter is measured and compared under quasi-static and industrial forming conditions (temperatures: 25 vs 200, 300 degrees C and strain rates: 10(-3)vs 10 s(-1)) for DP590 and DP800 steels. Resonance frequency and ultrasonic sound velocity techniques are utilized for the measurements to test the effectiveness and validity of each technique. At a given strain, the damage values can be up to 700% higher at industrial forming conditions, under which dynamic strain aging (DSA) controls the deformation behavior. DSA results in lower formability and is the likely mechanism responsible from the abnormal damage evolution. Measured damage parameters are also confirmed with the void fraction characterization by microscopy, which also provided details on the void shape and distribution with respect to the deformation conditions.Article Citation - WoS: 1Citation - Scopus: 1Flame Retarded Plasticized Poly(lactic Acid) Using Phosphorus-Based Additives(Sage Publications Ltd, 2024) Yesil, Sertan; Aytac, Ayse; Selim, FatmaIn this study, the synergistic effect of the flame-retardant additives on the properties of poly(lactic acid) (PLA) was investigated and at the same time, it was tried to increase the toughness of PLA by adding small amounts of phosphate-based additives to plasticized PLA as binary and ternary mixtures. Poly(ethylene glycol) (PEG) was used as a plasticizer. As flame retardant additives, ammonium polyphosphate (APP), tri-phenyl phosphate (TPP), and boron phosphate (BP) were used. Characterization of the composites was carried out by tensile test, impact test, differential scanning calorimetry (DSC), thermal gravimetric analyses (TGA), scanning electron microscopy (SEM), limiting oxygen index (LOI), and UL-94 horizontal burning tests. In addition, TGA-FTIR analyses were carried out to understand the thermal degradation mechanism of composites during combustion. According to the SEM micrographs of the burnt surfaces of the samples, a smooth and flat structure is observed in PLA/PEG/5TPP-5BP sample, while a porous structure and branching formations are observed in other composite samples. Among the composite samples, the best flame retardancy features were observed in the composite containing PLA/PEG/5APP-2.5TPP-2.5BP sample, and the highest impact strength and elongation at break values were obtained in the composite containing PLA/PEG/5APP-5TPP sample.Article Citation - WoS: 6Citation - Scopus: 4Latent Dynamics of Movement Formation: the Kurdish Case in Turkey (1940s-1960s)(Sage Publications Ltd, 2015) Ozen, HayriyeThe attention of social movement studies has so far tended to focus on visible phases of movements, neglecting latent ones. This study argues that invisible mobilizations may be critical in preparing the groundwork of public mobilizations, particularly in authoritarian contexts. Using a process-oriented constructivist account of mobilization which incorporates insights from resistance studies, this article analyzes the Kurdish case in Turkey in the authoritarian 1940s and semi-authoritarian 1950s. Based on in-depth interviews, memoirs, newspaper reports, and official documents, it is demonstrated that a latent Kurdish dissent emerged in this period through the constitution of a sense of shared grievance and common identity both in hidden ways within the submerged networks of Kurdish students and professionals, and in public and visible, yet disguised, ways. Incubating the movement out of the gaze of the authorities within the authoritarian context, this latent dissent formed the groundwork of public acts of defiance and mobilization which emerged towards the end of the 1950s as the political changes encouraged Kurdish dissenters to publicly declare their opposition, and expanded in the more liberal context of the 1960s. Resume Les etudes des mouvements sociaux ont eu tendance jusqu'a present a privilegier les phases visibles de ces mouvements, negligeant les stades latents. Cette etude soutient que les mobilisations invisibles peuvent etre essentielles pour preparer le terrain des mobilisations publiques, en particulier dans un contexte autoritaire. En s'appuyant sur une interpretation constructiviste, axee sur le processus de mobilisation et reunissant des idees tirees des etudes des mouvements de resistance, cet article analyse le cas kurde dans la Turquie autoritaire des annees quarante et semi-autoritaire des annees cinquante. Fonde sur des entretiens approfondis, des biographies, des articles de journaux et des documents officiels, ce travail met en evidence l'apparition au cours de cette periode d'une dissidence kurde latente grace a la constitution d'un sentiment partage de mecontentement et d'identite commune au sein des reseaux secrets des etudiants et professionnels kurdes, de facon a la fois invisible et publique, mais dissimulee. Couvant a l'abri des regards des gouvernements autoritaires, cette dissidence latente a pose les bases des manifestations publiques de defiance et de mobilisation qui sont apparues a la fin des annees cinquante a l'occasion des changements politiques ayant encourage les dissidents kurdes a declarer publiquement leur opposition et favorise les mouvements sociaux dans le contexte plus liberal des annees soixante. Resumen La atencion de los estudios sobre movimientos sociales hasta ahora ha tendido a centrarse en las fases visibles de los movimientos, dejando de lado los latentes. Este estudio sostiene que las movilizaciones invisibles pueden ser centrales para la preparacion de las bases de movilizaciones publicas, en particular en contextos autoritarios. A partir de un relato constructivista orientado a los procesos de movilizacion que incorpora perspectivas de estudios de resistencia, este trabajo analiza el caso kurdo en Turquia en la decada autoritaria de 1940 y semi-autoritaria de 1950. Sobre la base de entrevistas en profundidad, memorias, informes de prensa y documentos oficiales, se demuestra que una disidencia kurda latente surgio en este periodo a traves de la constitucion de un sentimiento de agravio compartida y de identidad comun tanto en formas ocultas dentro de las redes sumergidas de estudiantes y profesionales kurdos, asi como de maneras publicos y visibles, aunque disfrazadas. Incubando el movimiento fuera de la mirada de las autoridades en el contexto autoritario, esta disidencia latente formo las bases del acto publico de rebeldia y movilizacion que surgio a finales de la decada de 1950 como los cambios politicos alentados disidentes kurdos para declarar publicamente su oposicion, y ampliado en el contexto mas liberal de la decada de 1960.Article Citation - WoS: 76Citation - Scopus: 109Effect of Social Media Sharing on Destination Brand Awareness and Destination Quality(Sage Publications Ltd, 2020) Dedeoglu, Bekir Bora; van Niekerk, Mathilda; Kucukergin, Kemal Gurkan; De Martino, Marcella; Okumus, FevziThis study examines the effect of social media sharing on tourism destination brand awareness and destination natural and service quality and also examines the moderating roles of country of origin (COI; macro and micro) image on destination natural and service quality. Data were collected from 568 domestic and international tourists who have visited Alanya, Turkey. Relationships in the study were examined through structural equation modeling. As one of the components of social media sharing, participant sharing positively affects destination brand awareness, whereas any significant effect of nonparticipant sharing on destination brand awareness was not found. Destination brand awareness positively influences tourist perceptions of both destination service quality and destination natural quality. COI image moderates most of the relationships.Article Citation - WoS: 1Citation - Scopus: 1PMMA-Based Electrospun Composite Fibers for Dye Adsorption From Water(Sage Publications Ltd, 2025) Cakar, Ilknur; Yesil, Sertan; Bayram, GoknurPoly (methyl methacrylate) (PMMA) and PMMA/poly (ethylene glycol) (PEG)-based composite fibers were produced using electrospinning technique with two different additives; halloysite nanotubes (HNTs) and boron phosphate (BPO4). The effect of the additives on the morphology, wettability and dye adsorption properties of electrospun fibers were investigated by Scanning Electron Microscopy (SEM), water contact angle measurement and UV-VIS spectrophotometry. The results of SEM analysis indicated that addition of PEG resulted in thinner average fiber diameter and beaded structure. Additionally, it was also observed that incorporating both HNT and BPO4 to the PMMA solution caused increased fiber diameter which might be due to increased solution viscosity. For PMMA fibers containing 3 wt% HNT, the highest average diameter and water contact angle were measured as 2204 +/- 302 nm and 110.29 +/- 3.9 degrees, respectively. The produced fibers were tested for the capability to adsorb methylene blue (MB) and methyl orange (MO) from aqueous solutions. Dye adsorption capacity of the samples increased by addition of HNT and BPO4. According to adsorption capacity results, PMMA/PEG/BPO4 composite sample containing 5 wt% BPO4, with an adsorption capacity of 0.76 mg/g, was determined as adsorbent for kinetic and isotherm studies. The adsorption kinetics were well described by the pseudo-second-order model, and equilibrium data were correlated with the Langmuir model.Article The Mediating Role of Self-Compassion in the Relationship between Postpartum Depression and Breastfeeding Self-Efficacy(Sage Publications Ltd, 2025) Akdag Topal, Cansu; Mert Karadas, Merve; Karakurt, Irem; Boztepe, HandanPostpartum depression (PPD) may adversely affect breastfeeding self-efficacy, yet the underlying mechanisms remain unclear. This study explored whether self-compassion mediates the relationship between PPD and breastfeeding self-efficacy among Turkish women. An expert model was developed based on validated scales: the Self-Compassion Scale, the Edinburgh Postpartum Depression Scale, and the Postnatal Breastfeeding Self-Efficacy Scale-Short Form. In this cross-sectional study, 236 women (mean age: 28.71, SD = 6.16) were surveyed. Results showed that depression was negatively associated with self-compassion (beta = -0.474, p < 0.001), and self-compassion was positively associated with breastfeeding self-efficacy (beta = 0.785, p < 0.001). Mediation analysis indicated that self-compassion partially mediated the link between PPD and breastfeeding self-efficacy, with a significant indirect effect (-0.586, -0.209). Depression also had a direct negative effect on breastfeeding self-efficacy (beta = -0.484, p < 0.001). These findings suggest that fostering self-compassion may enhance maternal mental health and breastfeeding outcomes.Article Citation - WoS: 22Citation - Scopus: 24The Role of Covid-19 Anxiety and Social Contact Within Technology Readiness and Acceptance Model for Virtual Reality(Sage Publications Ltd, 2023) Ozekici, Yakup Kemal; Kucukergin, Kemal GurkanThis research aims to question the current threats posed by COVID-19 anxiety and the concept of social contact brought up by the pandemic, with the goal of extending the TRAM model within the context of tourism and virtual reality (VR). The sample of the study comprises of 300 participants taking part in a touristic activity within the last year and experiencing the lockdown period. Partial Least Squares Structural Equation Modeling (PLS-SEM) is used for data analysis. According to the findings, COVID-19 anxiety significantly enhances attitudes toward VR, social contact as a tourist role, and perceived usefulness (PU) toward VR. However, social contact is shown not to have a significant effect on attitudes toward VR. Lastly, technological readiness predicts perceived ease of use (PEOU) and PU of VR. The two, in turn, affect attitudes toward virtual reality technology (AVR), which positively affects behavioral intention toward virtual reality technology, namely, BIVR. Insights derived from the study extend present knowledge concerning TRAM, COVID-19 anxiety, virtual reality, social contact as a value, and provide various recovery marketing-oriented strategies for tourism professionals.Article Citation - WoS: 7Citation - Scopus: 6The Importance of the Calculation of Angle Factors To Determine the Mean Radiant Temperature in Temperate Climate Zone: a University Office Building Case(Sage Publications Ltd, 2022) Ozbey, Mehmet Furkan; Turhan, CihanThermal comfort depends on four environmental (air velocity, relative humidity, air temperature, mean radiant temperature) and two personal (clothing insulation and metabolic rate) parameters. Among all parameters, the mean radiant temperature (t(r)) is the most problematic variable in thermal comfort studies due to its complexity. Measurement methods, calculation methods and assumptions are mostly used to obtain the t(r). Researchers mainly prefer to obtain the t(r) via measurement methods or assumptions due to their easiness compared to the calculation methods. Besides, some researchers use constant values of angle factors in calculation methods. However, using constant values is not proper for every indoor environment, and it causes wrong estimations in the t(r) and thus the thermal comfort. This paper gives the importance of calculation of angle factors, with an example of a university office building in temperate climate zone, according to the ISO 7726. The angle factors of the room were calculated for a seated occupant from the centre of gravity in three different locations and compared with the constant angle factors. The results indicate that a significant difference (MAPE of 1.02) was found in the t(r) values, which were obtained by calculation of constant values of angle factors.Article Citation - WoS: 34Citation - Scopus: 37Peasants Against Mncs and the State: the Role of the Bergama Struggle in the Institutional Construction of the Gold-Mining Field in Turkey(Sage Publications Ltd, 2009) Ozen, Sukru; Ozen, HayriyeIn this article, we argue that the emergent literature that integrates the neo-institutional and social movement theories for a better understanding of institutional change offers a partial picture concerning the roles of the state and society in institutional wars due to its preoccupation with the liberal polities prevalent in the Anglo-Saxon countries. We suggest that the macro-institutional perspective that recognizes the influences of varied polities should be introduced to this emergent literature, if it is to provide a full picture. Incorporating the macro-institutional insights into the integrative approach, we examine a struggle between a group of protesters, a multinational gold-mining company and governmental actors regarding an environmental issue in Bergama, Turkey, where a statist polity mediates worldwide currents towards the neo-liberal order. The findings indicate that the Turkish state repressed the mobilizations against the neo-liberal construction of the mining field and reinforced the existing neo-liberal logic in the mining field through introducing a new regulatory framework. On the basis of the findings, we suggest that both the trajectory and consequences of institutional wars are influenced by the kind of polity in which they take place.Article Citation - WoS: 6Citation - Scopus: 6Multiple Sclerosis Experiences of Couples: Examination of Patient and Partner Perspectives(Sage Publications Ltd, 2022) Demirtepe-Saygili, DilekThe study aims to investigate Multiple Sclerosis (MS) experiences of couples. Using a dyadic qualitative method, separate simultaneous interviews were conducted with 20 couples, including one partner with MS. The themes resulting from content analysis were examined in two categories: Convergent (anxiety about future, acceptance of MS and MS as an accelerator of the relationship) and divergent (sexual problems, the experience of MS symptoms, the priority of the problems and untold issues). The findings revealed shared and unique perspectives of partners in the illness process, having the potential to guide the psychosocial interventions for couples living with a chronic illness.
