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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 Biotechnological Preparedness for Novel Pandemics: Diagnostic Performance of IVDS Against SARS-CoV(Wiley, 2025) Kavruk, Murat; Ercan, Meltem; Borsa, Baris Ata; Ozalp, Veli Cengiz; Hernandez, Frank J.Although the COVID-19 pandemic has created many challenges and negative impacts around the world, some of which will persist into the future, its technological challenge has created a unique opportunity in a globalized world. It is a rare event that almost all of humanity to be directed towards a single goal and to try to produce solutions, but the necessity of a similar global action in the future has begun to enter the agenda again. The predictions made on the basis of countries and institutions against the possibility of a pandemic, which is defined as Disease X, are shaped by the experience of the COVID-19 pandemic. Technologically, one of the know-how we have gained in this pandemic is the performance of IVD and test systems in terms of quality and quantity. A comprehensive analysis of the products produced by combining biotechnology with different strategies has not been conducted. In this context, we have analyzed the technical preferences, limitations, and other performance parameters of IVDs and test kits that could be developed against a future Disease X. The performance parameters of 2,882 biotechnological products listed for use in the European Union have been analyzed, and areas that could be targeted for increased effectiveness have been identified. Our study is the first of its kind in this field and can serve as a guide for those who want to work on detection methods, diagnostics, and novel technologies for deployment in future pandemics.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 The Role of Background Acoustic Stimuli in Dual Tasks: A Study on Postural Control Performance(Wiley, 2025) Saricamlik, Selin; Avci, Nizamettin Burak; Yigit, OznurIntroduction: Performing everyday tasks requires the use of multiple cognitive, sensory, and emotional systems. The interference of different variables in these multitasking systems affects our motor-balance system. This study was conducted to investigate how acoustic stimuli presented during a cognitive-motor dual task affect postural control in healthy young adults. Methods: Fifty-four healthy participants (39 females, 15 males; total age 21.87 +/- 1.18, range 19-24) were randomly assigned to control (silent), noise (multi-talker babble), or music (Mozart-Jupiter) groups based on testing environment. During the Stroop test, conducted with acoustic stimuli, postural sway velocity was measured on firm and foam surfaces with eyes open. The dual-task effect was assessed using the Wilcoxon test, and group comparisons employed one-way ANOVA or Kruskal-Wallis tests. Independent t tests and Mann-Whitney U tests were used for two-group comparisons. Statistical significance was set at p<0.05 (Bonferroni-adjusted p<0.017). Results: The silent cognitive-motor dual task increased postural sway on firm (median increased from 0.18 to 0.26 deg/s) and foam (median increased from 0.21 to 0.32 deg/s) surfaces. Music did not significantly affect cognitive performance or postural sway compared to the control group. However, noise reduced postural sway on firm and foam surfaces compared to the control group but did not affect cognitive performance. There was no significant difference in average Stroop response times between the groups or between the firm and foam surface comparisons. Conclusions: During inhibitory control tasks, cognitive effort prioritized in young people in easy-to-balance situations. Background noise affects motor-cognitive interaction, highlighting its potential for enhancing vestibular rehabilitation strategies in multitasking and guiding future research.Article Citation - WoS: 7Citation - Scopus: 6Oil and Stock Prices: New Evidence From a Time Varying Homogenous Panel Smooth Transitionvecmfor Seven Developing Countries(Wiley, 2022) Ceylan, Resat; Ivrendi, Mehmet; Shahbaz, Muhammed; Omay, TolgaThis paper investigates the relationship between international oil price and stock prices applying the time varying causality testing over the period of 2000(M1)-2017(M3). The panel unit root and panel cointegration tests considering cross-section dependence are also employed. A time varying panel smooth transition vector error correction (TV-PSTRVEC) model is a developed and estimated for testing the presence of non-linear short-run and long-run causality, and cointegrating relationship between stock and oil prices. The empirical findings indicate that short and long-run causalities between oil price and stock prices are time-dependent. Moreover, oil price cause stock prices in the long-run. In the short-run, neutral effect exists between oil price and stock prices. These two findings are evidence of a strong exogeneity of oil price in time-dependent regimes which is also supporting the recent arguments and empirical findings.Article Citation - Scopus: 1Predicting Stroke Risk Using Machine Learning: A Data-Driven Approach to Early Detection and Prevention(Wiley, 2025) Sutcu, Muhammed; Jouda, Dana; Yildiz, Baris; Katrib, Juliano; Almustafa, Khaled MohamadStroke is a major global health concern and a leading cause of disability and mortality, emphasizing the need for early risk prediction and intervention. This study leverages statistical analysis, machine learning (ML) classification, clustering, and survival modeling to identify key stroke predictors using a dataset of 5110 records. Descriptive statistics reveal that age, glucose levels, BMI, hypertension, and heart disease are the most influential risk factors. Stroke prevalence is notably higher among hypertensive (13.25%) and heart disease patients (17.03%), as well as among former (7.91%) and current smokers (5.32%). Clustering analysis using PCA and t-SNE highlights high-risk groups with elevated glucose levels and advanced age. Among ML models, XGBoost offers the best trade-off between precision and recall, while na & iuml;ve Bayes achieves the highest recall (0.404), detecting more stroke cases despite higher false positives. Feature importance analysis ranks glucose, BMI, and age as dominant predictors, with XGBoost emphasizing cardiovascular conditions. Survival analysis confirms increasing stroke risk beyond age 60, with the Kaplan-Meier and Cox models showing a 31.9% risk increase linked to hypertension. These findings underscore the importance of early screening, lifestyle intervention, and targeted care. Future research should explore data-balancing methods like SMOTE and develop real-time tools to support clinical decision-making.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 Citation - WoS: 23Citation - Scopus: 29Modeling of Dielectrophoretic Particle Motion: Point Particle Versus Finite-Sized Particle(Wiley, 2017) Cetin, Barbaros; Oner, S. Dogan; Baranoglu, BesimDielectrophoresis (DEP) is a very popular technique for microfluidic bio-particle manipulation. For the design of a DEP-based microfluidic device, simulation of the particle trajectory within the microchannel network is crucial. There are basically two approaches: (i) point-particle approach and (ii) finite-sized particle approach. In this study, many aspects of both approaches are discussed for the simulation of direct current DEP, alternating current DEP, and traveling-wave DEP applications. Point-particle approach is implemented using Lagrangian tracking method, and finite-sized particle is implemented using boundary element method. The comparison of the point-particle approach and finite-sized particle approach is presented for different DEP applications. Moreover, the effect of particle-particle interaction is explored by simulating the motion of closely packed multiple particles for the same applications, and anomalous-DEP, which is a result of particle-wall interaction at the close vicinity of electrode surface, is illustrated.Article Citation - WoS: 8Citation - Scopus: 8A New Rf and Microwave Engineering Course Enriched With Advanced Technologies(Wiley, 2012) Aydin, Elif; Cagiltay, NergizIn this study, a curriculum model including recent developments and technologies in the Radio Frequency (RF) and Microwave Engineering field by using a blended approach is proposed. This study covers the description of the content of theoretical and hands on applications, the integration model of the technological tools into the proposed curriculum, and the instructional approaches used in the new course design. The main goal of the course is to prepare students for future professional careers in RF and Microwave Engineering by supporting them with new instructional technologies. The secondary goal of the course is to better prepare the students for the sequence of senior courses in the Electrical and Electronics Engineering program of Atilim University. The course is structured with a balance between theory and laboratory, including remote and in lab measurement experiments as well as modeling and designing microwave components by means of computer tools and design fabrication. The newly designed course is implemented at the Atilim University. The study also reports the first semester implementation. (C) 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 634645, 2012Article Citation - WoS: 41Citation - Scopus: 53Brain Drain From Turkey: Return Intentions of Skilled Migrants(Wiley, 2014) Gungor, Nil Demet; Tansel, Aysit; Alemdaroğlu Temel, Mine; Alemdaroğlu Temel, MineThe study estimates an empirical model of return intentions using a dataset compiled from an internet survey of Turkish professionals residing abroad. In the migration literature, wage differentials are often cited as an important factor explaining skilled migration. The findings of our study suggest, however, that non-pecuniary factors, such as the importance of family and social considerations, are also influential in the return or non-return decision of the highly educated. In addition, economic instability in Turkey, prior intentions to stay abroad, and work experience in Turkey also increase non-return. Female respondents also appear less likely to return indicating a more selective migration process for females.
