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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, EnginBackground 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 - WoS: 9Citation - Scopus: 10Coherent System With Standby Components(Wiley, 2018) Eryilmaz, Serkan; Erkan, T. ErmanA coherent system that consists of n independent components and equipped with r cold standby components is considered. A generalized mixture representation for the survival function of such a system is obtained, and it is used to examine reliability properties of the system. In particular, the effect of adding r standby components to a given set of original components is measured by computing mean time to failure of the system. The limiting behavior of the failure rate of the system is also examined using the mixture representation. The results are illustrated for a bridge system. A case study that is concerned with an oil pipeline system is also presented.Article Citation - WoS: 8Citation - Scopus: 8Physical 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 Citation - WoS: 6Citation - Scopus: 4Is real per capita state personal income stationary? New nonlinear, asymmetric panel-data evidence(Wiley, 2020) Emirmahmutoglu, Furkan; Gupta, Rangan; Miller, Stephen M.; Omay, TolgaThis paper re-examines the stochastic properties of U.S. state real per capita personal income, using new panel unit-root procedures. The new developments incorporate non-linearity, asymmetry, and cross-sectional correlation within panel-data estimation. Including nonlinearity and asymmetry finds that 43 states exhibit stationary real per capita personal income whereas including only nonlinearity produces 42 states that exhibit stationarity. Stated differently, we find that two states exhibit nonstationary real per capita personal income when considering nonlinearity, asymmetry, and cross-sectional dependence.Article A 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.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.Letter Citation - WoS: 3Citation - Scopus: 3Global Robust Stability of Interval Delayed Neural Networks: Modified Approach(Wiley, 2009) Singh, VimalA criterion for the global robust stability of Hopfield-type delayed neural networks with the intervalized network parameters is presented. The criterion, which is derived by utilizing the idea of splitting the given interval into two intervals, is in the form of linear matrix inequality and, hence, computationally tractable. The criterion yields a less conservative condition compared with many recently reported criteria, as is demonstrated with an example. Copyright (C) 2008 John Wiley & Sons, Ltd.Article Citation - WoS: 5Citation - Scopus: 7China's Charm Defensive: Image Protection by Acquiring Mass Entertainment(Wiley, 2020) Yildirim, Nilgun Elikucuk; Aslan, MesutFocusing on discussion of China's soft power resources, this article argues that China performs two kinds of soft power strategies in developing and developed countries: offensive and defensive, respectively. While China's charm offensive aims to consolidate her comprehensive power through a development model, aid, investment, traditional culture, foreign policy, and international broadcasting in developing countries, the defensive aspect of China's soft power strategy aims to soften the rise of China with traditional culture by introducing appealing parts of Chinese culture through investments and international broadcasting in Western countries. China applies classical soft power tools in developing countries while she endeavors to protect her image in Western countries defensively. China's alternative defensive approach to soft power is mostly implemented through the acquisition of media outlets, and via the entertainment sector and gaming industry by Chinese-owned companies. However, even in the defensive and offensive bifurcation, if charm attacks result in failure, China could turn take a defensive stance in developing countries.Article A Case Study on the Assessment of Rf Switch and Splitter Options for Coupling of Transceiver Modules To Bidirectional Antennas Employed in Linear Wireless Sensor Networks(Wiley, 2021) Dalveren, Yaser; Durukan, Ahmet Mert; Kara, AliRecently, a concept of linear wireless sensor networks (LWSNs) has attracted much attention. For such networks, one of the key challenges in sensor node design is to couple transceiver modules with bidirectional antennas placed back-to-back for opposite radiation. As is known, simply, this can be achieved by using well-known coupling options like radio frequency (RF) switch or splitter. However, it is important to decide between two seemingly equally good options according to the system requirements such as RF performance, power consumption, and cost. Therefore, this study aims to comparatively assess these options from the system level point of view to find out what advantages or disadvantages either provides as per the other from widespread use of them in a LWSN-based cathodic protection monitoring of oil and natural gas pipelines in extreme environments. Preliminary field tests are also conducted to validate the efficiency of coupling options for LWSN links. Results show that RF splitter offers low power consumption and cost whereas RF switch has advantages of low loss. Thus, it is believed that this study may provide useful insights to design bidirectional sensor links for LWSNs.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.
