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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.Article Information-Theoretic Approach in Allometric Scaling Relations of Dna and Proteins(Wiley, 2022) Adiguzel, YekbunAllometric scaling relations can be observed in between molecular parameters. Hence, we looked for presence of such relation among sizes (i.e., lengths) of proteins and genes. Protein lengths exist in the literature as the number of amino acids. They can also be derived from the mRNA lengths. Here, we looked for allometric scaling relation by using such data and simultaneously, the data was compared with the sizes of genes and proteins that were obtained from our modified information-theoretic approach. Results implied presence of scaling relation in the calculated results. This was expected due to the implemented modification in the information-theoretic calculation. Relation in the literature-based data was lacking high goodness of fit value. It could be due to physical factors and selective pressures, which ended up in deviations of the literature-sourced values from those in the model. Genome size is correlated with cell size. Intracellular volume, which is related to the DNA size, would require certain number of proteins, the sizes of which can therefore be correlated with the protein sizes. Cell sizes, genome sizes, and average protein and gene sizes, along with the number of proteins, namely the expression levels of the genes, are the physical factors, and the molecular factors influence those physical factors. The selective pressures on those can act through the connection between those physical factors and limit the dynamic ranges. Biological measures could be prone to such forces and are likely to deviate from expected models, regardless of the validity of assumptions, unless those are also implemented in the models. Yet, present discrepancies could be pointing at the need for model improvement, data imperfection, invalid assumptions, etc. Still, current work highlights possible use of information-theoretic approach in allometric scaling relations' studies.Article Citation - WoS: 103Citation - Scopus: 160Cassava Disease Recognition From Low-Quality Images Using Enhanced Data Augmentation Model and Deep Learning(Wiley, 2021) Abayomi-Alli, Olusola Oluwakemi; Damasevicius, Robertas; Misra, Sanjay; Maskeliunas, RytisImprovement of deep learning algorithms in smart agriculture is important to support the early detection of plant diseases, thereby improving crop yields. Data acquisition for machine learning applications is an expensive task due to the requirements of expert knowledge and professional equipment. The usability of any application in a real-world setting is often limited by unskilled users and the limitations of devices used for acquiring images for classification. We aim to improve the accuracy of deep learning models on low-quality test images using data augmentation techniques for neural network training. We generate synthetic images with a modified colour value distribution to expand the trainable image colour space and to train the neural network to recognize important colour-based features, which are less sensitive to the deficiencies of low-quality images such as those affected by blurring or motion. This paper introduces a novel image colour histogram transformation technique for generating synthetic images for data augmentation in image classification tasks. The approach is based on the convolution of the Chebyshev orthogonal functions with the probability distribution functions of image colour histograms. To validate our proposed model, we used four methods (resolution down-sampling, Gaussian blurring, motion blur, and overexposure) for reducing image quality from the Cassava leaf disease dataset. The results based on the modified MobileNetV2 neural network showed a statistically significant improvement of cassava leaf disease recognition accuracy on lower-quality testing images when compared with the baseline network. The model can be easily deployed for recognizing and detecting cassava leaf diseases in lower quality images, which is a major factor in practical data acquisition.Article Citation - WoS: 14Citation - Scopus: 14How Can We Get Benefits of Computer-Based Testing in Engineering Education?(Wiley, 2013) Cagiltay, Nergiz; Yaman, Seniz-OzalpUsing computers for assessment can provide several benefits for educators and test-takers. However, in the literature, there is no consensus on the equivalence of paper-and-pencil (P&P) and computer-based test (CBT) environments. Additionally, these studies fail to address the engineering domain. Our main assumption is that, if we could define the confounding factors to satisfy that these two versions of the tests provide equivalent results, then especially in the first year courses of the engineering education programs, we could get several benefits of the CBT environments. Accordingly, in this study, students' performance on different test modes was evaluated on 209 first year engineering students of a chemistry course. The results of this study showed that there is no significant performance difference between P&P and CBT. By comparing results with the previous studies, this study concludes that personal characteristics of test takers, the features of CBT systems, and the test content are all possible confounding factors when comparing test modes and need to be considered by the implementers. The results of this study show that once these factors are controlled, students' performance on CBTs and P&P tests in chemistry courses will not vary. This finding is encouraging the educators to get benefits of CBTs without any affect on students' performance. (c) 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 287293, 2013; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.20470Article Citation - WoS: 2Citation - Scopus: 3Internationalization Journey of Healthcare Providers: the Case of Turkish Acibadem Healthcare Group(Wiley, 2022) Uner, M. Mithat; Cetin, Burak; Eroglu, Sevgin; Cavusgil, S. TamerThe advances in technology and global deregulation have led to the progressive internationalization of professional services, notably, the healthcare industry. The present case study examines the remarkable internationalization journey of Acibadem Healthcare Group (AHG) by scrutinizing the dynamics and outcomes of the agile and innovative strategies which propel their achievements. The case of AHG shows that successful internationalization in the service industry, in general, and healthcare, in particular, is not solely in the domain of large, established companies from advanced economies, but those ventures with liabilities of origin, newness, and size can also succeed with smart strategies and resourceful leveraging of their competitive advantages. The study provides unique insights on strategic management for successful internationalization of the healthcare services within an emerging market context and suggests future research avenues in this fast-growing field of inquiry.Article Citation - WoS: 5Citation - Scopus: 6Evaluation of Hematological Parameters in Patients Using Systemic Isotretinoin With Diagnosis of Acne Vulgaris(Wiley, 2023) Elif, Demirci Saaadet; Şahin, Uğur; Ugur, Sahin; Şahin, UğurObjectivesOral isotretinoin is the most effective treatment option in patients with acne. However, it can cause various hematologic and biochemical abnormalities. This study aimed to evaluate hematologic abnormalities during oral isotretinoin treatment in patients with acne. Material and MethodsIn this cross-sectional study, the hematologic and inflammatory parameters of 138 patients with acne using 0.3-1 mg/kg/day oral isotretinoin for at least 6 months were retrospectively analyzed. ResultsIn the study, the female-to-male ratio was 2.83, and the mean age of the patients was 23.1 +/- 5.8 years. At the third and sixth months of isotretinoin treatment, there was a statistically significant decrease in the neutrophil count compared to the pre-treatment values (p = 0.003 and p = 0.032, respectively). The platelet count showed the most statistically significant increase (p < 0.001) at the first month of treatment. The most statistically significant decrease in the neutrophil-to-lymphocyte ratio (NLR) was observed at the third month of treatment (p < 0.001). No significant changes were observed in hemoglobin, hematocrit, white blood cell count, mean corpuscular volume, and mean platelet volume. ConclusionsThere was a decrease in neutrophils and NLR and an increase in platelets during isotretinoin treatment, and these changes were usually mild. However, it would be appropriate to monitor blood counts during treatment in patients with neutropenia or thrombocytosis.Article Citation - WoS: 4Citation - Scopus: 4Template-free microsphere and hollow sphere formation of polymethylanilines(Wiley, 2009) Icli, Merve; Onal, Ahmet M.; Cihaner, AtillaBACKGROUND: Microsphere and/or hollow sphere formation of methyl-substituted polyaniline derivatives was investigated via chemical polymerization where different sets of conditions were examined. It was found that a variety of parameters (e.g. types and concentrations of monomer and oxidant, polymerization time, solvent with and without acid) have a crucial influence on the morphology of the resulting polyaniline derivatives. RESULTS: Structures with desired morphologies (with or without microspheres and hollow spheres) may be obtained in a controlled manner by changing the parameters. Moreover, the electrochemical and optical properties of the polymers in the presence of acid and/or base were investigated via cyclic voltammetry and UV-visible and electron spin resonance spectroscopic techniques. It is noteworthy that the morphologies of microspheres and/or hollow spheres remained unchanged after repeated acid and base treatments. CONCLUSION: Micro/hollow spherical structures were successfully prepared via chemical polymerization of various substituted anilines by using ammonium persulfate as oxidant. It was found that the type of oxidant and monomers along with the polymerization time are quite important factors for the formation of micro/hollow spheres. Furthermore, hydrogen bond formation does not play any crucial role for the formation of these spheres. Chemically and electrochemically doped/dedoped states of microspheres and/or hollow spheres are very sensitive, and give rapid response towards vapours of HCl and NH3, which makes them amenable for use in sensors. (c) 2009 Society of Chemical IndustryEditorial Discussion of Signature-Based Models of Preventive Maintenance(Wiley, 2023) Eryilmaz, Serkan[No Abstract Available]
