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Article Citation - WoS: 2Citation - Scopus: 2Potential Role of SGLT-2 Inhibitors in Improving Allograft Function and Reducing Rejection in Kidney Transplantation(Wiley, 2025) Demir, Mehmet Emin; Helvaci, Ozant; Yildirim, Tolga; Merhametsiz, Ozgur; Sezer, SirenSodium-glucose cotransporter-2 inhibitors (SGLT-2i) have demonstrated renoprotective and cardioprotective benefits beyond their antiglycemic effects. Their potential utility in kidney transplant recipients (KTRs) for preserving graft function and reducing rejection risk is currently under active investigation. Preliminary studies indicate that SGLT-2i therapy stabilizes estimated glomerular filtration rate (eGFR), decreases glomerular hyperfiltration, and improves metabolic outcomes in KTRs. Emerging clinical evidence also suggests that SGLT-2i may be associated with reduced rates of acute rejection, although direct immunosuppressive actions remain unclear. Experimental findings further suggest that SGLT-2i modulates gene regulation pathways involved in inflammation, oxidative stress, and fibrosis, contributing to improved allograft outcomes. Current safety data in KTRs are reassuring, without significant increases in urinary tract infections or adverse graft events. Nevertheless, long-term prospective studies specific to transplant populations are lacking. This review summarizes available evidence regarding the mechanisms of action, clinical efficacy, and safety profile of SGLT-2i in kidney transplantation, emphasizing their metabolic, hemodynamic, inflammatory, and immunomodulatory effects.Article Citation - WoS: 2Citation - Scopus: 2Investigations of Ph-Dependent Dynamic Properties of Ompg-16sl, an Outer Membrane Protein G Mutant by Atr-Ftir Spectroscopy(Elsevier, 2022) Yilmaz, Irem; Korkmaz, FilizIn this paper, the dynamic properties of outer membrane protein G mutant (OmpG-16SL) are investigated with ATR-FTIR spectroscopy. While OmpG-WT has 14 beta-strands in its structure, the mutant is designed to have 16 beta-strands with the intention of creating an enlarged pore. Loop L6 is elongated by introducing six residues, two of which are negatively charged. The solvent accessibility of the OmpG-16SL mutant is compared with WT and a previously reported mutant OmpG-16S by tracking the H-1/H-2 exchange kinetics in acidic and neutral buffer conditions. The exchange kinetics and dynamics in the fast and slow exchange phases are separately investigated using the 2DCOS technique, which enables the tracking of the structural changes at each phase of the exchange process. The results suggest that the mutant OmpG-16SL is equally exposed to buffer in both acidic and neutral pH conditions. Additionally, the time range in the fast phase is very short - one-tenth of that for WT - and most of the exchange is completed in this phase. This fast exchange within minutes is also indicative of the presence of highly flexible and/or unstructured regions. In all, the fast exchange rates independent of the buffer pH justify the assumption that there is an altered interaction among the charged residues, which leads to a steadily-open pore. The role of the side-chain interactions within the pore and between the loops involving the loop L6 is also discussed.Article Citation - WoS: 19Citation - Scopus: 18Deviations From Born-Oppenheimer Theory in Structural Chemistry: Jahn-Teller, Pseudo Jahn-Teller, and Hidden Pseudo Jahn-Teller Effects in C3h3< and C3h3<(Amer Chemical Soc, 2013) Kayi, H.; Garcia-Fernandez, P.; Bersuker, I. B.; Boggs, J. E.The electronic structure and vibronic coupling in two similar molecular systems, radical C3H3 and anion C3H3-, in ground and excited states, are investigated in detail to show how their equilibrium structures, in deviation from the Born-Oppenheimer approximation, originate from the vibronic mixing of at least two electronic states, producing the Jahn-Teller UT), pseudo JT (PJT), and hidden PJT effects. Starting with the high-symmetry geometry D3h of C3H3, we evaluated its 2-fold degenerate ground electronic state 2E" and two lowest excited states 2A,' and 2E' and found that all of them contribute to the distortion of the ground state via the JT vibronic coupling problem E" e' and two PJT problems (E" + A(1)') circle star e" and (E" + E') circle times (a2" + e"); all the three active normal modes e'(1335 e"(1030 cm(-1)), and a2"(778 cm(-1)) are imaginary, meaning that all the three vibronic couplings are sufficiently strong to cause instability, albeit in different directions. The first of them, the ground state JT effect, enhances one of the C-C bonds (toward an ethylenic form with C-2v symmetry), while the two PJT effects produce, respectively, cis (a(2)" toward C-3v symmetry) and trans (e") puckering of the hydrogen atoms. As a result, C3H3 has two coexisting equilibrium configurations with different geometry. In the C3H3- anion, the ground electronic state in DA symmetry is an orbitally nondegenerate spin triplet (3)A(2)' with a group of close in energy singlet and triplet excited states in the order of (1)A(1),', (3)A(1)', E-1", E-3", and E-1'. This shows that two PJT couplings, (3A(2)' + (3)A(1)") circle times a(2)" and (3A2' + 3E") e", may influence the geometry of the equilibrium structure in the 3A2' state. Indeed, both vibrational modes, a(2)"(1034 cm(-1)) and e"(1284 cm(-1)), are imaginary in this state. Similar to the radical case, they produce, respectively, cis (a(2)") and trans (e") puckering of the hydrogen atoms, but no e' distortion of the basic C-3 triangle; the equilibrium configuration with Cs symmetry occurs along the stronger e" distortions. Another higher-in-energy triplet-state minimum with C-2v symmetry emerges as a result of a strong JTE in the excited 3E" electronic state. In addition to these APES minima with spin-triplet electronic states, the system has a coexisting minimum with a spin-singlet electronic state, which is shown to be due to the hidden PJT effect that couples two singlet excited states. The two lowest equilibrium configurations of the C3H3- anion with different geometry and spin realize a (common to all electronic e(2) configurations) magnetic and structural bistability accompanied by a spin crossover. Some general spectroscopic consequences are also noted. As a whole, this article is intended to demonstrate the efficiency of the vibronic coupling approach in rationalizing the origin of complicated structural features of molecular systems as due to a combination of nonadiabatic JT effects.Article Citation - WoS: 5Citation - Scopus: 7Deadline-Aware Energy-Efficient Query Scheduling in Wireless Sensor Networks With Mobile Sink(Hindawi Ltd, 2013) Karakaya, MuratMobile sinks are proposed to save sensor energy spent for multihop communication in transferring data to a base station (sink) in Wireless Sensor Networks. Due to relative low speed of mobile sinks, these approaches are mostly suitable for delay-tolerant applications. In this paper, we study the design of a query scheduling algorithmfor query-based data gathering applications using mobile sinks. However, these kinds of applications are sensitive to delays due to specified query deadlines. Thus, the proposed scheduling algorithm aims to minimize the number of missed deadlines while keeping the level of energy consumption at the minimum.Article Citation - WoS: 8Citation - Scopus: 10Biomechanical Effects of Two Different Collar Implant Structures on Stress Distribution Under Cantilever Fixed Partial Dentures(Taylor & Francis Ltd, 2011) Meric, Gokce; Erkmen, Erkan; Kurt, Ahmet; Eser, Atilim; Ozden, Ahmet UtkuObjective. The purpose of the study was to compare the effects of two distinct collar geometries of implants on stress distribution in the bone around the implants supporting cantilever fixed partial dentures (CFPDs) as well as in the implant-abutment complex and superstructures. Materials and methods. The three-dimensional finite element method was selected to evaluate the stress distribution. CFPDs which was supported by microthread collar structured (MCS) and non-microthread collar structured (NMCS) implants was modeled; 300 N vertical, 150 N oblique and 60 N horizontal forces were applied to the models separately. The stress values in the bone, implant-abutment complex and superstructures were calculated. Results. In the MCS model, higher stresses were located in the cortical bone and implant-abutment complex in the case of vertical load while decreased stresses in cortical bone and implant-abutment complex were noted within horizontal and oblique loading. In the case of vertical load, decreased stresses have been noted in cancellous bone and framework. Upon horizontal and oblique loading, a MCS model had higher stress in cancellous bone and framework than the NMCS model. Higher von Mises stresses have been noted in veneering material for NMCS models. Conclusion. It has been concluded that stress distribution in implant-supported CFPDs correlated with the macro design of the implant collar and the direction of applied force.Article Citation - WoS: 1Citation - Scopus: 1Does the Immigration Affect Prenatal Attachment Levels?(Routledge Journals, Taylor & Francis Ltd, 2023) Tekmen, Ezgi Kubra; Boztepe, Handan; Topal, Cansu AkdagPregnancy is an important period in which mother-infant attachment begins, includes bio-psychological changes, and has physical and psychological effects on the future life of the fetus. This study aims to evaluate the prenatal attachment levels of Syrian refugee and Turkish mothers in Turkey and to determine the variables that affect these. This cross-sectional study conducted in the obstetric outpatient clinics with 397 pregnant women 197 Syrian and 200 native women. Inclusion criteria were a pregnancy of at least 20 weeks, no communication or mental disorders, no chronic diseases, no diagnosis of high -risk pregnancy, literacy in the pregnant Turkish women, Turkish language proficiency in the pregnant Syrian women, and residence in Turkey for at least three years. Data were collected using a Sociodemographic form and The Prenatal Attachment Inventory (PAI). The data were analyzed by conduct-ing independent t-tests, and hierarchical multiple linear regression analysis. The mean prenatal attachment score of Turkish pregnant women (61.79 +/- 8.55) was higher than Syrian women (48.38 +/- 10.39) (p < .05). Education level, pre-pregnancy counseling, regular checkup, support from spouses, relatives, and friends, and being a refugee of pregnant women were determined as predictors of prenatal attachment. The results showed that 67 percent of the total variance in the prenatal attachment levels could be explained in model 2 (F = 35.524, R2 variation = .673, p = .001). The low prenatal attachment level of Syrian pregnant women was a result of the detrimental impacts of being a refugee on pregnancy. The integration of transcultural knowledge, culture-specific perspectives, and cross-cultural theories into clinical practices is essen-tial for immigrant women.Article Citation - WoS: 5Citation - Scopus: 9The mediating role of FoMO and the moderating role of narcissism in the impact of social exclusion on compulsive buying: a cross-cultural study(Springer int Publ Ag, 2023) Mert, Merve; Tengilimoglu, DilaverBackground There is an interrelationship between the concepts of social exclusion, compulsive buying behavior, fear of missing out (FoMO), and narcissism. Nevertheless, the extent to which these concepts mediate or moderate their relationships with each other has not been efficiently investigated. Objective This research aims to investigate how FoMO mediates and narcissism moderates the correlation between social exclusion and compulsive buying behavior. In addition, the research aims to test a conceptual model and highlight the differences that may occur in the conceptual model proposed in two different countries. Methods This model was analyzed among 1007 university students (Turkey = 506, Denmark = 501). The study used scales to measure social exclusion, compulsive buying behavior, FoMO, and narcissism. The study employed PROCESS Model 4 to analyze direct and indirect (mediation) effects and PROCESS Model 59 to assess conditional (moderation) effects. Furthermore, the Johnson-Neyman technique was utilized to investigate interaction terms. Results The findings indicate that those who face social exclusion tend to participate more in compulsive buying, and this connection is partly explained by FoMO. This suggests that individuals who encounter social exclusion may have an increased likelihood of experiencing FoMO, which may subsequently contribute to compulsive buying behavior. Furthermore, the moderating effect of narcissism differed between the Turkey and Danish samples. Specifically, in the Turkey sample, narcissism only modified the connection between social exclusion and FoMO, while in the Danish sample, it impacted both the connection between social exclusion and FoMO and the connection between FoMO and compulsive buying. Conclusion The obtained results show that the regulating role of narcissism is different in Turkey and Denmark within the conceptual model we studied.Editorial Intracranial Dermoid Cyst Mimicking a Thrombosed Giant Aneurysm of the Anterior Communicating Artery(Ma Healthcare Ltd, 2022) Ogul, Hayri; Koksa, Ali; Kaya, Serhat; Kantarci, Mecit; Eren, Suat[No Abstract Available]Article Citation - WoS: 27Effect of Van Der Waals Interactions on the Chemisorption and Physisorption of Phenol and Phenoxy on Metal Surfaces(Aip Publishing, 2016) Pekoz, Rengin; Donadio, DavideThe adsorption of phenol and phenoxy on the (111) surface of Au and Pt has been investigated by density functional theory calculations with the conventional PBE functional and three different non-local van derWaals (vdW) exchange and correlation functionals. It is found that both phenol and phenoxy on Au(111) are physisorbed. In contrast, phenol on Pt(111) presents an adsorption energy profile with a stable chemisorption state and a weakly metastable physisorbed precursor. While the use of vdW functionals is essential to determine the correct binding energy of both chemisorption and physisorption states, the relative stability and existence of an energy barrier between them depend on the semi-local approximations in the functionals. The first dissociation mechanism of phenol, yielding phenoxy and atomic hydrogen, has been also investigated, and the reaction and activation energies of the resulting phenoxy on the flat surfaces of Au and Pt were discussed. Published by AIP Publishing.Article Citation - WoS: 4New Criteria on Oscillatory and Asymptotic Behavior of Third-Order Nonlinear Dynamic Equations With Nonlinear Neutral Terms(Mdpi, 2021) Grace, Said R.; Alzabut, Jehad; Ozbekler, AbdullahIn the paper, we provide sufficient conditions for the oscillatory and asymptotic behavior of a new type of third-order nonlinear dynamic equations with mixed nonlinear neutral terms. Our theorems not only improve and extend existing theorems in the literature but also provide a new approach as far as the nonlinear neutral terms are concerned. The main results are illustrated by some particular examples.
