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Article Citation - WoS: 1Citation - Scopus: 1Left Ventricular Geometry as a Predictor of Carotid Artery Stenosis Severity in Patients Undergoing Carotid Artery Stenting(Wiley, 2020) Karaduman, Bilge Duran; Ayhan, Huseyin; Keles, Telat; Bozkurt, Engin; Duran Karaduman, BilgeBackground and Aim Cerebrovascular diseases are the second most common cause of death worldwide. Moderate and severe carotid artery stenosis causes nearly 10% of all strokes. LV geometry is a familiar prognostic and diagnostic factor in several populations; yet, data on its role in carotid artery stenosis are unknown. In our study, we investigated the prognostic value of LV geometry in predicting carotid artery stenosis severity in patients undergoing carotid artery stenting. Methods Patients who underwent carotid artery stenting between January 2012 and January 2016 at our tertiary care center were evaluated retrospectively. Two hundred fifty-five patients who underwent carotid artery stenting were included in the study. Accessible echocardiographic documentation of ninety-eight patients was accessed and evaluated. Results LV normal geometry was detected in 37 (37.7%) of the 98 carotid artery stenting (CAS) patients, concentric hypertrophy in 13 (13.2%), eccentric hypertrophy in 9 (9.1%), and concentric remodeling in 39 (39.7%). By a majority, distal filter was used in normal geometry and eccentric hypertrophy groups (82.9% vs 100%, P: .017). Considering the relationship between carotid artery stenosis severity and LV geometry, we determined that the stenosis severity was statistically significantly higher in the concentric hypertrophy group (p:0.012). However, although no complications were detected in the concentric hypertrophy group, it did not reach statistical significance between the groups (P: .058). LVMi and as expected, Doppler velocity showed a significant correlation with stenosis severity (r = .23 vs .54; P: .021, <.001, respectively). Conclusion Echocardiographic evaluation of LV geometry provided prognostic information in the development of carotid artery stenosis. Abnormal LV geometry is an independent predictor in detecting the severity of carotid artery stenosis undergoing carotid artery stenting.Article Citation - Scopus: 1Stenotic Double-Orifice Mitral Valve After Surgical Repaired Partial Atrioventricular Septal Defect(Wiley, 2020) Duran Karaduman, Bilge; Torun, Ayse Nur; Ayhan, Huseyin; Keles, Telat; Bozkurt, EnginDouble-orifice mitral valve (DOMV) is an uncommon congenital anomaly account for 1% of congenital heart disease. However, accurate diagnosis and evaluation of valve stenosis or regurgitation and other concomitant congenital anomalies due to DOMV are required to obtain suitable treatment. Two- and three-dimensional echocardiography can contribute valuable functional and anatomic information that can support to reach this goal. Here, we present a case of complete bridge-type DOMV that causes mitral stenosis after surgical repair of the partial atrioventricular septal defect in childhood.Article Citation - WoS: 9Citation - Scopus: 9Physical fitness and activities of daily living in primary ciliary dyskinesia: A retrospective study(Wiley, 2022) Sonbahar-Ulu, Hazal; Cakmak, Aslihan; Inal-Ince, Deniz; Vardar-Yagli, Naciye; Yatar, Ilker; Calik-Kutukcu, Ebru; Ozcelik, UgurBackground Primary ciliary dyskinesia (PCD) is a rare, hereditary, autosomal recessive disorder characterized by recurrent upper and lower respiratory tract infections. This study aimed to compare pulmonary function, respiratory muscle strength, exercise capacity, physical fitness, and activities of daily living (ADLs) retrospectively between patients with PCD and healthy controls. Methods Data from 20 patients with PCD and 20 matched, healthy counterparts recorded between July 2015 and January 2017 were analyzed. The data evaluated and recorded included pulmonary function using a portable spirometer, respiratory muscle strength (using a mouth pressure device, exercise capacity using the incremental shuttle walk test,), physical fitness (using the Munich Fitness Test), and ADLs (using the Glittre ADL test). Results Pulmonary function, respiratory muscle strength, incremental shuttle walk test scores (all parameters), and total Munich Fitness Test scores were lower in the PCD group relative to controls (P < 0.05). The duration to complete the Glittre ADL test was higher in PCD patients than in healthy subjects (P < 0.05). Conclusions Pulmonary function, respiratory muscle strength, exercise capacity, physical fitness, and ADL were affected by PCD. Thus, pulmonary rehabilitation regimens should be tailored according to these impacts.Article Validating the Turkish Adaptation of the Fear of Being Single Scale(Wiley, 2024) Kirimer-Aydinli, Fulya; Kucukkomurler, SanemPeople may experience anxiety regarding their future romantic relationship status. Fear of being single (FOBS) is a potential cause of this anxiety, characterized by distress about the idea of being single and assessed through the FOBS Scale. In the current study, the FOBS Scale was adapted into Turkish. The study included 349 individuals aged 28-55 years (M = 23.63 years, SD = 6.45 years). The reliability and validity of the measure and the associations with particular variables were investigated for the first time in the cultural context of Turkey. The confirmatory factor analysis revealed an acceptable model fit for the single-factor structure. Measurement invariance of the scale across relationship status was supported at configural and metric levels, but not at the scalar level. The convergent and divergent validity analyses indicated that FOBS is distinct from generalized anxiety, attachment anxiety, and the personality trait of neuroticism. FOBS was found to be related to the need to belong but not to the inclusion of close others into the self. It has been determined that FOBS is a distinctive phenomenon, and the Turkish version of the FOBS Scale is a valid and reliable tool for assessing FOBS in Turkey.Article Citation - WoS: 1Citation - Scopus: 1A Class of Shock Models for a System That Is Equipped With a Protection Block With an Application to Wind Turbine Reliability(Wiley, 2025) Eryilmaz, SerkanThis paper studies a class of shock models for a system that is equipped with a protection block that has its own failure rate. Under the considered class, the system exposed to shocks at random times is protected by the protection block, and the probability of the shock damaging the system varies depending on whether the protection block operates or not. The system failure criteria is defined based on the pattern of the critical/damaging shocks. Exact expressions for the reliability and mean time to failure of the system are obtained, and detailed computations are presented for the run shock model, which is included in the class. The application of the extreme shock model, which is included in the relevant class, to wind turbine reliability is also discussed.Editorial Discussion of Signature-Based Models of Preventive Maintenance(Wiley, 2023) Eryilmaz, Serkan[No Abstract Available]Article Citation - WoS: 6Citation - Scopus: 9Comparative Assessment of Electromagnetic Simulation Tools for Use in Microstrip Antenna Design: Experimental Demonstrations(Wiley, 2019) Bilgin, Gulsima; Yilmaz, Vadi Su; Kara, Ali; Aydin, ElifThis paper presents a better understanding of the use of finite integration techniques (FIT) and finite element method (FEM) in different types of microstrip antennas in order to determine which numerical method gives relatively more accurate results. Although the theoretical formulation based on Maxwell's equations of both FEM and FIT are approached from different aspects in the literature, there is still a lack of comparison of the same antenna type using different numerical methods employing FEM and FIT. Therefore, in this study, FEM and FIT were applied to two different types of microstrip antennas, and their simulation and experimental results was compared. For the first antenna demonstration, a multilayer structure was chosen to achieve one of the significant parameters. Then, a microstrip antenna with a compact structure was used in the second demonstration. Using these two antennas, the accuracy of FEM and FIT in different structures were compared and all simulated return loss and gain results were verified by the measured results. The experimental demonstrations show that FEM performs better for both types of microstrip antennas while FIT provides an adequate result for two-layer microstrip antennas.Article Citation - WoS: 6Citation - Scopus: 6Effect of Nutritional Support on Nutritional Status and Inflammation in Malnourished Patients Undergoing Maintenance Hemodialysis(Wiley, 2021) Demirci, Bahar Gurlek; Carrero, Juan Jesus; Tutal, Emre; Bal, Zeynep; Sezer, Siren; Gurlek Demirci, BaharIntroduction Protein energy wasting/malnutrition is a strong predictor of morbidity and mortality in patients on maintenance hemodialysis (MHD). We aimed to compare the effects of oral and/or intradialytic parenteral nutrition (IDPN) support on nutritional and inflammatory parameters in malnourished patients with MHD. Methods This is an observational study of 56 malnourished patients on MHD. We offered combined oral nutritional support (ONS) and IDPN for 12 months to all patients. Depending on patient choices for treatment, they were classified into four groups: group 1 (ONS only), group 2 (IDPN only), group 3 (both ONS and IDPN), and group 4 (patients who refused artificial nutrition support and only followed dietary advice). Normalized protein catabolic rate (nPCR), malnutrition inflammation score (MIS), and body composition (fat mass [FM], muscle mass [MM]) were assessed monthly. Findings The mean serum albumin levels of groups 2 and 3 significantly increased with the intervention, whereas that of group 4 significantly decreased. The mean nPCR levels of groups 2 and 3 significantly increased. Group 3 had the most significant positive change in serum albumin and nPCR levels. Mean serum C-reactive protein (CRP) levels of groups 1, 2, and 3 decreased, whereas those of group 4 increased. A increment in CRP was only identified in group 3. The MIS of groups 1, 2, and 3 significantly decreased whereas that of group 4 significantly increased. The increment % in FM was 1.1, 1.9, 9.1, and -2.9 for groups 1, 2, 3, and 4, respectively, and that in MM was -0.6, 4.4, 6.9, and -7.9 for groups 1, 2, 3, and 4, respectively. Discussion Compared to monotherapy or nutritional counseling, the choice of ONS plus IDPN is associated with improved nutritional status and decreased inflammation in malnourished patients on MHD. Nonetheless, interventional studies must be conducted to confirm these observations.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: 27Citation - 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.
