WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394
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Article Activation and Avoidance Mediate the Relationship Between Depression and Life Satisfaction: Insights from Behavioral Activation Therapy(Springer, 2026) Koşan, Yavuz; Kaya, M. SiyabendBehavioral activation therapy has been increasingly used in depression intervention in recent years. It aims to increase the activation level and decrease the avoidance level. In this way, the individual's life satisfaction is expected to increase while trying to reduce depression. However, the relationship between depression and life satisfaction in behavioral activation therapy-based interventions has not been sufficiently revealed. Furthermore, the effects of activation and avoidance, which are the most basic concepts of behavioral activation therapy, and their underlying mechanisms are not well understood. Therefore, this study focused on this gap and aimed to explore the mediating roles of activation and avoidance variables in the relationship between depression and life satisfaction. Participants (N = 440) from a non-clinical sample group completed various self-report scales on depression, behavioral activation, and life satisfaction. Our results showed that depression and life satisfaction negatively predicted each other, and that activation and avoidance variables mediated this relationship in parallel. Accordingly, increasing activation and decreasing avoidance in young people with depressive symptoms may be an effective way to improve life satisfaction and reduce depression. Effective prevention efforts that reduce depression can increase the life satisfaction levels of young adults. In summary, behavioral activation and avoidance can be used to prevent depression and increase life satisfaction. The current study provides more information about the applicability of activation and avoidance, two important elements of behavioral activation therapy, in depression intervention.Article Unveiling the Therapeutic Role of 3D-Cultured Mesenchymal Stem Cells in Diabetic Foot Ulcers through Transcriptomic Integration and Fibroblast Modulation(Springer, 2026-03-31) Ozturk, Esengul; Bicer, MesudeBackground Diabetic foot ulcers (DFUs) are among the most severe complications of diabetes mellitus and remain difficult to manage due to chronic inflammation, defective angiogenesis, delayed tissue repair, which increase the risk of recurrence and limb amputation. Standard treatments, such as debridement, infection management, pressure off-loading and revascularization, are commonly used, however; these interventions often inadequate to fully restore effective wound repair. Mesenchymal stem cells (MSCs) have attracted remarkable interest due to their potential regenerative ability and paracrine activity. Nevertheless, the molecular interaction between MSCs and fibroblasts under hyperglycemic conditions has not been fully elucidated. Objective This study aimed to examine differentially expressed genes (DEGs) associated with DFUs and MSC-related regenerative mechanisms using transcriptomic datasets (such as GSE143735, GSE199939, and GSE217709). Methods and results Differentially expressed genes and protein-protein interaction (PPI) network analysis were performed to determine central regulatory genes. Four key genes including CXCL1, MMP9, THBS1, and POSTN were recognized as hub genes related to inflammatory response, extracellular matrix reorganization, and angiogenesis. For experimental validation, L929 murine fibroblasts were exposed to high-glucose conditions to set-up an in vitro diabetic model and subsequently treated with MSCs with/without a 3D platform. Hyperglycemic conditions significantly reduced fibroblast proliferation and migration downregulated the expression of the identified hub genes and enhanced apoptotic activity. MSC treatment partially increased cellular function, while MSCs embedded into 3D culture enhanced a more pronounced recovery in both gene expression patterns and functional assays. Conclusions These findings suggest that high glucose impair fibroblast functions for wound repair, while 3D-cultured MSCs enhance regenerative responses and may represent a promising strategy for diabetic wound healing.Article Wireless Communication System Design for Point Machine Detection and Monitoring in Railways(Springer, 2026-03-09) Talu, Burak; Cetin, Fatih; Kilic, Veli Tayfun; Elden, Burakhan; Sanlier, Saban DuranThis paper reports on a wireless communication system that is used in railways to instantly detect and continuously monitor point machine positions. Also, with the system the position information is transmitted wirelessly to a train driver. The designed system is composed of TX and RX units. It has a compact structure and is fully modular. The TX unit of the system is placed near the railway point machines and the RX unit is located on a train. The designed system was constructed, and measurements were obtained on-site. Results show that the system point machine position data were accurately transmitted at 1350 m range which is much longer than the safe braking distance of a train. In addition, the measured 1 s data sampling time of the system allows the driver to continuously monitor current RPM positions as well as state changes. The maximum delay was found to be 3 s in the limit range of the communication. It is found that the system has a low power consumption and the designed system can work for long hours. The findings indicate that the designed wireless communication system has a high potential to be used in railways to prevent accidents and contribute to the overall safety and efficiency of operations.Article Deep-Learning Detection of Open-Apex Teeth on Panoramic Radiographs Using YOLO Models(Springer, 2025-12-23) Edik, Merve; Celebi, Fatma; Cukurluoglu, AykaganObjectivesThe use of deep learning in detecting teeth with open apices can prevent the need for additional radiographs for patients. The presented study aims to detect open-apex teeth using You Only Look Once (YOLO)-based deep learning models and compare these models.MethodsA total of 966 panoramic radiographs were included in the study. Open-apex teeth in panoramic radiographs were labeled. During the labeling process, they were divided into 6 classes in the maxilla and mandible, namely incisors, premolars, and molars. AI models YOLOv3, YOLOv4, and YOLOv5 were used. To evaluate the performance of the three detection models, both overall and separately for each class in the test dataset, precision, recall, average precision (mAP), and F1 score were calculated.ResultsYOLOv4 achieved the highest overall performance with a mean average precision (mAP) of 87.84% at IoU (Intersection over Union) 0.5 (mAP@0.5), followed by YOLOv5 with 85.6%, and YOLOv3 with 84.46%. Regarding recall, YOLOv4 also led with 90%, while both YOLOv3 and YOLOv5 reached 89%. Moreover, the F1 score was the highest for YOLOv4 (0.87), followed by YOLOv3 (0.86) and YOLOv5 (0.85).ConclusionsIn this study, YOLOv3, YOLOv4, and YOLOv5 were evaluated for the detection of open-apex teeth, and their mAP, recall, and F1 scores exceeded 84%. Deep learning-based systems can provide faster and more accurate results in the detection of open-apex teeth. This may help reduce the need for additional radiographs from patients and aid dentists by saving time.Article Citation - WoS: 17Citation - Scopus: 23Women's Tertiary Education Masks the Gender Wage Gap in Turkey(Springer, 2017-03-10) Tekguc, Hasan; Eryar, Deger; Cindoglu, DilekThis paper investigates the gender wage gap for full-time formal sector employees, disaggregated by education level. The gap between the labor force participation rate of women with tertiary education and those with lower levels of education is substantial. There is no such gap for men. Hence, existing gender wage gap studies for Turkey, where we observe lopsided labor force participation rates by education levels, compare two very different populations. We disaggregate the whole sample by education level to create more homogenous sub-groups. For Turkey, without disaggregation, the gender wage gap was 13% in 2011, and women are significantly over-qualified relative to men on observed characteristics. Once we disaggregate the sample by education level, we show that the gender wage gap is 24% for less educated women and 9% for women with tertiary education in full-time formal employment. Observed characteristics only explain 1 % of this gap in absolute terms. We further disaggregate the data by public and private employment. The gender gap is higher in the private sector. However, women with tertiary education in the public sector are significantly better qualified compared to men, and consequently the adjusted gender wage gap is higher for women with tertiary education in the public sector. Our estimates also indicate a rise in the gender wage gap between 2004 and 2011.Article Citation - WoS: 3Citation - Scopus: 3Theoretical Investigation of Substituent Effects on the Relative Stabilities and Electronic Structure of [BnXn]2- Clusters(Springer, 2021-11-29) Tahaoglu, Duygu; Alkan, Fahri; Durandurdu, MuratIn this study, we provide a theoretical evaluation of relative stabilities and electronic structure for [BnXn](2-) clusters (n = 10, 12, 13, 14, 15, 16). Structural and electronic characteristics of [BnXn](2-) clusters are examined by comparison with the [B12X12](2-) counterparts with a focus on the substituent effects (X = H, F, Cl, Br, CN, BO, OH, NH2) on the electronic structure, electron detachment energies, formation enthalpies, and charge distributions. For the electronic structure and electron detachment energies, substituent effects on boron clusters are shown to follow a very similar trend to the mesomeric and inductive effects (+/- M and +/- I) of pi-conjugated systems, and the most stable derivatives in terms of HOMO/LUMO and electron detachment energies are calculated for CN and BO substituents due to strong -M effects. In the case of formation enthalpies for larger boron clusters (n >= 13), the icosahedral barrier is shown to increase with the halogen and CN substitution, whereas it is possible to reduce the icosahedral barrier for the cases of X = OH and NH2. It is shown that this reduction results from destabilizing the [B12X12](2-) cluster with electronic (+ M) and symmetry effects induced by OH and NH2 ligands.Article Citation - WoS: 11Citation - Scopus: 12The Effect of Dilute Nitrogen on Nonlinear Optical Properties of the IngaAsN/GaAs Single Quantum Wells(Springer, 2012-09-26) Koksal, K.; Sahin, M.In this study, we investigate the linear and third order nonlinear optical properties of InGaAsN/GaAs depending on nitrogen content and laser dressing parameter. As theoretical models, band anticrossing and model solid theory are used. In order to obtain the electronic properties of the quantum well, the finite difference method is used. The laser beam affects the electronic properties of the quantum well by changing the shape of the confinement potential. This modification of the potential is determined by laser dressing parameter. By using dilute amount of nitrogen, conduction band and the depth of quantum well can be controlled. The strain which is introduced due to the presence of nitrogen can be compensated by using indium atoms. The electronic and the linear and third order nonlinear optical properties of InGaAsN/GaAs quantum well structure are obtained.Article Citation - WoS: 32Citation - Scopus: 33Synthesis and Characterization of Chitosan-Vermiculite Composite Beads for Removal of Uranyl Ions: Isotherm, Kinetics and Thermodynamics Studies(Springer, 2020-11-19) Senol, Zeynep Mine; Simsek, Selcuk; Ozer, Ali; Senol Arslan, DilekIn this study, a new material containing Chitosan (Ch)-Vermiculite (V) composite beads was synthesized with epichlorohydrin cross-linking agent and used to remove uranyl ions from the aqueous solution. The prepared new material was characterized by SEM, XRD, FTIR analyses and PZC measurement. The effects of significant parameters on adsorption including temperature, pH, concentration and time were investigated. The obtained results indicated that the new composites of Ch-V was revealed in different structure. The zeta potential analyses showed that electrostatic attraction existed during the adsorption process between the uranyl ions and Ch-V. The maximum adsorption capacity of material was calculated as 0.665 mol kg(-1) by considering Langmuir equation. Adsorption kinetic was also explained with pseudo second order and intra particular diffusion models. Experimental studies clearly showed that the adsorption was endothermic and occurred spontaneously. The newly developed smart material has many advantages such as reusability, high adsorption capacity, selectivity and economics.Article Citation - WoS: 28Citation - Scopus: 29Socio-Economic Determinants of Student Mobility and Inequality of Access to Higher Education in Italy(Springer, 2019-02-12) Turk, UmutThis paper introduces a modified version of the Hansen-gravity model as a framework to estimate the accessibility of higher education (HE) institutions in Italy from equal opportunities perspective. The fundamental assumption underlying gravity models is that accessibility decreases with spatial distance from opportunities. The paper extends the gravity equation to include socio-economic factors influencing the access to HE. The findings reveal differences in response to quality and other institutional characteristics by parental background and gender. Finally, decomposition of overall inequality into spatial and aspatial components reveals both the physical and social distance between groups of students seeking higher education opportunities in the country.Article Citation - WoS: 6Citation - Scopus: 8Sleep Assistive Dynamic Bandwidth Assignment Scheme for Passive Optical Network (PON)(Springer, 2018-09-14) Butt, Rizwan Aslam; Faheem, M.; Ashraf, M. Waqar; Idrus, Sevia M.In passive optical network (PON), in addition to efficient bandwidth management, a dynamic bandwidth assignment (DBA) scheme can also enhance the energy efficiency performance of the optical networks units (ONUs) during sleep mode. A few such green DBA schemes have been proposed in literature for EPON, however, ITU compliant PONs have not got attention. In this study, the role of a DBA scheme during the cyclic sleep mode for XGPON has been investigated. A sleep assistive (SA)-DBA scheme is proposed that not only improves the energy saving performance of cyclic sleep mode but also reduces the upstream delays and variance for all the type-2 (T2), type-3 (T3) and type-4 (T4) traffic classes. Although, the upstream delay of type-1 (T1) traffic class slightly increases, the average upstream delay of all the traffic classes remains below the set target delay limit of 56ms.