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Article Citation - WoS: 12Citation - Scopus: 14The Markov Discrete Time Δ-Shock Reliability Model and a Waiting Time Problem(Wiley, 2022) Chadjiconstantinidis, Stathis; Eryilmaz, Serkandelta-shock model is one of the widely studied shock models in reliability theory and applied probability. In this model, the system fails due to the arrivals of two consecutive shocks which are too close to each other. That is, the system breaks down when the time between two successive shocks falls below a fixed threshold delta. In the literature, the delta-shock model has been mostly studied by assuming that the time between shocks have continuous distribution. In the present paper, the discrete time version of the model is considered. In particular, a proper waiting time random variable is defined based on a sequence of two-state Markov dependent binary trials and the problem of finding the distribution of the system's lifetime is linked with the distribution of the waiting time random variable, and we study the joint as well as the marginal distributions of the lifetime, the number of shocks and the number of failures associated with these binary trials.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: 26Citation - Scopus: 28Reliability Assessment for Discrete Time Shock Models Via Phase-Type Distributions(Wiley, 2021) Eryilmaz, Serkan; Kan, CihangirIn this paper, particular shock models are studied for the case when the times between successive shocks and the magnitudes of shocks have discrete phase-type distributions. The well-known shock models such as delta shock model, extreme shock model, and the mixed shock model which is obtained by combining delta and extreme shock models are considered. The probability generating function and recursive equation for the distribution of the system's lifetime are obtained for the cases when the interarrival times between shocks and the magnitudes of shocks are independent and when they are dependent. System reliability is computed for particular interarrival distributions such as geometric, negative Binomial and generalized geometric distributions.Conference Object GC Contents of the Genes May Imply Associations with Coronary Artery Disease, Autism, Obesity, and Type 2 Diabetes(Wiley, 2025) Adiguzel, Y.; Yekeler, S. E.; Mohamed, A. A.; Turker, D.; Ozcan, L. E.; Sert, G.; Acet, K.Article Comparative Assessment and Performance Analysis of Interference Mitigation Techniques for Co-Existent Non-Geostationary and Geostationary Satellites(Wiley, 2024) Ozturk, Faik; Aydin, Elif; Kara, AliIn recent years, technological developments with user demands, reduced production, and launch costs have rapidly increased the number of Low Earth Orbit (LEO) satellites in space. Since LEO satellites use the same frequency band as existing Geostationary Earth Orbit (GEO) satellites, the interference coordination between the two satellite networks is vital. In order to minimize the co-existent interference between these satellite networks, studies perform on different interference mitigation strategies. In this paper, analysis and comparative assessment of these interference mitigation techniques are presented for the co-existent Non-Geostationary Earth (NGEO) and GEO systems. More specifically, power control (PC) and spatial isolation-based link adaptation (SILA) techniques are studied comparatively for the performance evaluation. It is shown that the communication link bandwidth is more efficiently utilized in the SILA technique when compared with the PC technique. Moreover, the multi-objective optimization problem (MOP) approach in the SILA technique is demonstrated to be more effective when compared with the single-objective optimization problem (SOP) approach used in the PC technique as the simultaneous prioritizing objective functions outperforms single prioritization. Finally, it is shown that when the PC technique is applied together with the SILA technique, the exclusive angle (EA) can be reduced up to 8% for 100 Mbps, and 8.5% for 200 Mbps transmission bit rates in different operational scenarios. The presented performance evaluation in this paper may help the satellite operator or decision-maker gain insights on which mitigation technique can be used in the case of a co-existent interference. This paper proposes analysis and comparative assessment of interference mitigation techniques for the co-existent Non-Geostationary Earth (NGEO) and Geostationary Earth Orbit (GEO) systems. Spatial isolation-based link adaptation (SILA) and power control (PC) techniques are studied comparatively for the performance evaluation. The obtained optimization results show that the communication link bandwidth is more efficiently utilized in the SILA technique when compared with the PC technique because of the simultaneous prioritizing of objective functions. imageArticle Citation - WoS: 42Citation - Scopus: 47Color-Emotion Associations in Interiors(Wiley, 2020) Gunes, Elif; Olgunturk, NilgunEmotional reactions to red, green, blue, and gray colors in a living room were investigated using a self-report measure. Participants first watched a short video of a 3D model of a living room. Next, they were asked to match the living rooms with facial expressions of six basic emotions. The most stated emotions associated for the red room were disgust and happiness, while the least stated emotions were sadness, fear, anger, and surprise; for the green room, neutral and happiness were the most stated emotions, and anger, surprise, fear, and sadness were the least stated ones; for the blue room, neutral was the most stated emotion, while the least stated emotions were anger and surprise. Neutral, disgust, and sadness were the most stated emotions for the gray room. Gender differences were not found in human emotional reactions to living rooms with different wall colors.Article Real Interest Rate Parity in Latin American Countries: Evidence from New Panel Unit Root Tests(Wiley, 2026) Omay, Tolga; Abioglu, Vasif; Hasanli, MubarizIn this study, we test the empirical validity of the real interest rate parity hypothesis for 15 Latin American countries over the period 2005-2023. To this end, we employ a battery of panel unit root tests to examine stochastic properties of the real interest rate differentials (RIDs) of the countries under consideration. The panel unit root tests that allow for both the cross-sectional dependence and the nonlinearities in the adjustment process do not reject the null of unit root for the most of these countries, suggesting that the real interest rate parity hypothesis does not hold for these countries. On the other hand, the panel unit root test that allows for smooth structural changes produces results consistent with the real interest rate parity hypothesis for 12 out of 15 Latin American countries. These findings imply that various shocks, including political, economic, and financial upheavals, can cause significant structural shifts in the RIDs of Latin American countries.Article Citation - WoS: 3Citation - Scopus: 3Hot aluminum substrate induced hexagonal-tetragonal phase transitions in InSe and performance of Al/InSe/Cu2O pn tunneling devices(Wiley, 2020) Qasrawi, Atef Fayez; Kmail, Reham RedaIn the current study, we have considered the induced phase transitions in Al/InSe thin film substrates and employing them for fabrication of InSe/Cu2O tunneling channels. The InSe substrates are observed to prefer the transition from the hexagonal gamma-In(2)Se(3)to the rarely observed tetragonal InSe. The phase transitions are obtained by the thermally assisted diffusion of aluminum, which was already kept at 250 degrees C in a vacuum media of 10(-5)mbar before the compensation of InSe. The tetragonal InSe also induced the crystallization of orthorhombic Cu2O with acceptable level of lattice matching along thea-axis. The Al/InSe/Cu2O/Au heterojunctions, which are electrically analyzed are observed to exhibit rectifying features with the current conduction being dominated by electric fields assisted thermionic emission (tunneling) through a barrier of width of 5.5 to 14.0 nm and barrier height of 0.19 to 0.30 eV. The ac analyses of the capacitance and conductance spectra of this device have shown that it can exhibit high/low capacitance and frequency dependent conductance switching modes at 0.12 GHz in addition to negative capacitance effect in the range of 0.12 to 1.80 GHz. The features of the device are promising as they indicate the suitability of the device for fabrication of field effect transistors, memory devices, and ultrafast switches.Editorial Citation - Scopus: 4Discussion of 'start-up Demonstration Tests: Models, Methods and Applications, With Some Unifications'(Wiley, 2014) Eryilmaz, Serkan; Eryılmaz, Serkan; Eryılmaz, Serkan; Industrial Engineering; Industrial Engineering[No Abstract Available]Article Morning Blood Pressure Surge in Renal Transplant Recipients: Its Relation To Graft Function and Arterial Stiffness(Wiley, 2022) Demirci, Bahar Gurlek; Afsar, Baris; Tutal, Emre; Colak, Turan; Sezer, SirenBackground: When the blood pressure rises before awakening in the morning, it is called as morning blood pressure pulse (MBPS). MBPS is considered to be an independent risk factor for cardiovascular disease. The aim of this study was to investigate the associations between MBPS, graft function, arterial stiffness and echocardiographic indices in renal transplant recipients. Methods: Among 600 renal transplant recipients, 122 patients who had a history of hypertension and were taking at least one anti hypertensive medication were enrolled in the study. Arterial stiffness was measured by carotid-femoral pulse wave velocity (PWv), and echocardiographic indices were assessed. 24 h ambulatory blood pressure was monitored for all patients. MBPS was calculated by subtracting morning systolic blood pressure from minimal asleep systolic blood pressure. Results: Mean morning, day time and asleep systolic blood pressure values were 171.2 +/- 23.9, 137.9 +/- 18.1, and 131.7 +/- 18.9, respectively. Nondipper hypertension status was observed in 93 patients. Mean MBPS was 35.6 +/- 19.5 mm Hg, means PWv was 6.5 +/- 2.0 m/s. Patients with MBPS >= 35 mm Hg, had significantly lower eGFR and higher proteinuria, PWv. higher left atrium volume and LVMI. In regression analysis, day time systolic blood pressure, asleep systolic blood pressure, morning blood pressure surge, nondipper status and left ventricular mass index were detected as the predictors of graft function. Conclusions: Increased morning blood pressure surge is associated with graft dysfunction, increased arterial stiffness and LVMI that contribute to cardiovascular mortality and morbidity in renal transplant recipients.
