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Book Part Citation - Scopus: 2Trace Element Containing Nano-HAp for Preventing Musculoskeletal Infections(Springer Science and Business Media B.V., 2021) Gizer,M.; Boyacıoğlu,Ö.; Korkusuz,P.; Korkusuz,F.Musculoskeletal infections are difficult to diagnose and rapidly reach the chronic phase that is difficult to treat. Osteomyelitis and septic arthritis are inflammatory musculoskeletal diseases and their recovery should contain bone or joint regeneration approaches. Nanometer-sized hydroxyapatite is the main inorganic component of the bone tissue that resembles its extracellular matrix. Nanometer-sized hydroxyapatite composite is also an efficient carrier for various regenerative molecules and medicine. Trace elements on the other hand enhance bone formation, mineralization and have antibacterial properties. Bioactivity, biocompatibility, and antibacterial properties of nanometer-sized hydroxyapatite can be gained and improved with trace elements such as zinc, boron, magnesium, strontium, and molybdenum. This chapter summarizes studies on the effects of zinc, boron, magnesium, strontium, and/or molybdenum-doped nanometer-sized hydroxyapatite that can be used to treat musculoskeletal infections. © 2021, The Author(s), under exclusive license to Springer Nature Switzerland AG.Article Citation - WoS: 45Citation - Scopus: 45An Ambipolar Low Band Gap Material Based on Bodipy and Edot(Elsevier Science Bv, 2009) Algi, Fatih; Cihaner, AtillaA novel donor-acceptor type conducting polymer based on BODIPY dye as acceptor and EDOT units as donor parts is synthesized electrochemically. The unique combination of BODIPY and EDOT units provides an ambipolar (n- and p-doping processes) low band gap material (4). This is the first example of p-n junction in an organic pi-conjugated material where BODIPY unit is incorporated directly in the main chain. Furthermore, the polymer film exhibits electrochromic behavior upon p-doping: a color change from light violet (neutral) to indigo (oxidized). (C) 2009 Elsevier B.V. All rights reserved.Book Part Citation - Scopus: 1Community Development, Frustration and Overtourism(Emerald Group Publishing Ltd., 2021) Koç,B.; Küçükergin,K.G.Tourism and community development are two complementary variables. There are many studies in the literature examining the effects of tourism on society. However, the number of studies focussing on the subject from the perspective of overtourism is still very limited. Although a shrinking in tourism demand is estimated for the next few years due to Covid-19, it is expected that the sector will face an even more intense tourist boom around the world after this health crisis. Therefore, the phenomenon of overtourism remains important. In this context, a conceptual examination was made in the current chapter regarding the observed and possible effects of tourism density on communities. The existing literature clearly shows that being successful in the long term is impossible with a tourism plan that uses natural resources, infrastructure facilities and traditional values of the region to create tourist demand but ignores the wishes and well-being of the community residents. © 2021 by Emerald Publishing Limited.Article Citation - WoS: 47Citation - Scopus: 67Deep Learning Based Fall Detection Using Smartwatches for Healthcare Applications(Elsevier Sci Ltd, 2022) Sengul, Gokhan; Karakaya, Murat; Misra, Sanjay; Abayomi-Alli, Olusola O.; Damasevicius, RobertasWe implement a smart watch-based system to predict fall detection. We differentiate fall detection from four common daily activities: sitting, squatting, running, and walking. Moreover, we separate falling into falling from a chair and falling from a standing position. We develop a mobile application that collects the acceleration and gyroscope sensor data and transfers them to the cloud. In the cloud, we implement a deep learning algorithm to classify the activity according to the given classes. To increase the number of data samples available for training, we use the Bica cubic Hermite interpolation, which allows us to improve the accuracy of the neural network. The 38 statistical data features were calculated using the rolling update approach and used as input to the classifier. For activity classification, we have adopted the bi-directional long short-term memory (BiLSTM) neural network. The results demonstrate that our system can detect falling with an accuracy of 99.59% (using leave-one-activityout cross-validation) and 97.35% (using leave-one-subject-out cross-validation) considering all activities. When considering only binary classification (falling vs. all other activities), perfect accuracy is achieved.Article Citation - WoS: 4Citation - Scopus: 4The Effect of Cerium Oxide (ceo2) on Ischemia-Reperfusion Injury in Skeletal Muscle in Mice With Streptozocin-Induced Diabetes(Mdpi, 2024) Ozer, Abdullah; Sengel, Necmiye; Kucuk, Ayseguel; Yigman, Zeynep; Ozdemir, Cagri; Kilic, Yigit; Arslan, MustafaObjective: Lower extremity ischemia-reperfusion injury (IRI) may occur with trauma-related vascular injury and various vascular diseases, during the use of a tourniquet, in temporary clamping of the aorta in aortic surgery, or following acute or bilateral acute femoral artery occlusion. Mitochondrial dysfunction and increased basal oxidative stress in diabetes may cause an increase in the effects of increased reactive oxygen species (ROS) and mitochondrial dysfunction due to IRI. It is of great importance to examine therapeutic approaches that can minimize the effects of IRI, especially for patient groups under chronic oxidative stress such as DM. Cerium oxide (CeO2) nanoparticles mimic antioxidant enzymes and act as a catalyst that scavenges ROS. In this study, it was aimed to investigate whether CeO2 has protective effects on skeletal muscles in lower extremity IRI in mice with streptozocin-induced diabetes. Methods: A total of 38 Swiss albino mice were divided into six groups as follows: control group (group C, n = 6), diabetes group (group D, n = 8), diabetes-CeO2 (group DCO, n = 8), diabetes-ischemia/reperfusion (group DIR, n = 8), and diabetes-ischemia/reperfusion-CeO2 (group DIRCO, n = 8). The DCO and DIRCO groups were given doses of CeO2 of 0.5 mg/kg intraperitoneally 30 min before the IR procedure. A 120 min ischemia-120 min reperfusion period with 100% O-2 was performed. At the end of the reperfusion period, muscle tissues were removed for histopathological and biochemical examinations. Results: Total antioxidant status (TAS) levels were found to be significantly lower in group DIR compared with group D (p = 0.047 and p = 0.022, respectively). In group DIRCO, total oxidant status (TOS) levels were found to be significantly higher than in group DIR (p < 0.001). The oxidative stress index (OSI) was found to be significantly lower in group DIR compared with group DCO (p < 0.001). Paraoxanase (PON) enzyme activity was found to be significantly increased in group DIR compared with group DCO (p < 0.001). The disorganization and degeneration score for muscle cells, inflammatory cell infiltration score, and total injury score in group DIRCO were found to be significantly lower than in group DIR (p = 0.002, p = 0.034, and p = 0.001, respectively). Conclusions: Our results confirm that CeO2, with its antioxidative properties, reduces skeletal muscle damage in lower extremity IRI in diabetic mice.Article Citation - WoS: 17Citation - Scopus: 17Productivity and Growth in an Unstable Emerging Market Economy: the Case of Turkey, 1960-2004(Routledge Journals, Taylor & Francis Ltd, 2009) Ismihan, Mustafa; Metin-Ozcan, KivilcimThis paper explores sources of growth in the Turkish economy by performing growth accounting exercises over the 1960-2004 period and relevant subperiods. It also analyzes the role of a number of important policy-related factors, such as infrastructure investment, macroeconomic instability, and imports, on total factor productivity (TFP) by performing cointegration and impulse response analyses. The results suggest that both TFP and capital accumulation were crucial sources of growth during the sample period. Nevertheless, TFP growth displayed enormous variation from 1960 to 2004. The descriptive and empirical evidence suggests that TFP is positively affected by imports and public infrastructure investment and negatively affected by macroeconomic instability.Article Citation - WoS: 1Citation - Scopus: 1On the Rate of Convergence for the q-durrmeyer Polynomials in Complex Domains(Walter de Gruyter Gmbh, 2024) Gurel, Ovgu; Ostrovska, Sofiya; Turan, MehmetThe q-Durrmeyer polynomials are one of the popular q-versions of the classical operators of approximation theory. They have been studied from different points of view by a number of researchers. The aim of this work is to estimate the rate of convergence for the sequence of the q-Durrmeyer polynomials in the case 0 < q < 1. It is proved that for any compact set D subset of C, the rate of convergence is O(q(n)) as n -> infinity. The sharpness of the obtained result is demonstrated.Article Citation - WoS: 22Citation - Scopus: 21Principal and Nonprincipal Solutions of Impulsive Differential Equations With Applications(Elsevier Science inc, 2010) Ozbekler, A.; Zafer, A.We introduce the concept of principal and nonprincipal solutions for second order differential equations having fixed moments of impulse actions is obtained. The arguments are based on Polya and Trench factorizations as in non-impulsive differential equations, so we first establish these factorizations. Making use of the existence of nonprincipal solutions we also establish new oscillation criteria for nonhomogeneous impulsive differential equations. Examples are provided with numerical simulations to illustrate the relevance of the results. (C) 2010 Elsevier Inc. All rights reserved.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: 34Citation - Scopus: 34Friction Stir Processing of Dual Phase Steel: Microstructural Evolution and Mechanical Properties(Elsevier Science inc, 2019) Aktarer, S. M.; Kucukomeroglu, T.; Davut, K.The influence of friction stir processing (FSP) on the microstructure and mechanical properties of a DP 600 steel has been studied. The microstructure evolution during the FSP has been characterized using electron back scatter diffraction (EBSD) technique and scanning and transmission electron microscopes. Standard tension and hardness tests were used to characterize the mechanical properties. The results show that the FSP produced a refined microstructure composed of ferrite, bainite, martensite, and tempered martensite which in turn increased the hardness and strength magnitudes by a factor of 1.5. The initially 2.83 mu m average grain size of ferrite has decreased to 0.79 mu m in the pin effected zone of (PE-SZ-I) of the processed region. Both EBSD and TEM observations showed regions with high dislocation density and sub-structures region in the processed zone. The grain size became coarser, the density of both dislocations and low-angle grain boundaries decrease, away from the processed zone. Moreover, phase fractions and hardness values were predicted using CALPHAD thermodynamic based software based on commercial material properties. Although the prediction does not take into consideration the influence of severe plastic deformation, the results were within 10% uncertainties of the experimental findings. The present study demonstrates that an ultra-fine grained structure can be obtained through the thickness of a 1.5 mm thick D P600 steel sheet via FSP. FSP can produce a range of different hardness and strength values; which can also be predicted successfully by inputting the composition and local temperatures reached during the FSP.
