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Review Citation - WoS: 64Citation - Scopus: 75Atmospheric Pressure Plasma Surface Treatment of Polymers and Influence on Cell Cultivation(Mdpi, 2021) Sasmazel, Hilal Turkoglu; Alazzawi, Marwa; Alsahib, Nabeel Kadim AbidAtmospheric plasma treatment is an effective and economical surface treatment technique. The main advantage of this technique is that the bulk properties of the material remain unchanged while the surface properties and biocompatibility are enhanced. Polymers are used in many biomedical applications; such as implants, because of their variable bulk properties. On the other hand, their surface properties are inadequate which demands certain surface treatments including atmospheric pressure plasma treatment. In biomedical applications, surface treatment is important to promote good cell adhesion, proliferation, and growth. This article aim is to give an overview of different atmospheric pressure plasma treatments of polymer surface, and their influence on cell-material interaction with different cell lines.Data Paper Citation - WoS: 44Citation - Scopus: 64A Database for the Radio Frequency Fingerprinting of Bluetooth Devices(Mdpi, 2020) Uzundurukan, Emre; Dalveren, Yaser; Kara, AliRadio frequency fingerprinting (RFF) is a promising physical layer protection technique which can be used to defend wireless networks from malicious attacks. It is based on the use of the distinctive features of the physical waveforms (signals) transmitted from wireless devices in order to classify authorized users. The most important requirement to develop an RFF method is the existence of a precise, robust, and extensive database of the emitted signals. In this context, this paper introduces a database consisting of Bluetooth (BT) signals collected at different sampling rates from 27 different smartphones (six manufacturers with several models for each). Firstly, the data acquisition system to create the database is described in detail. Then, the two well-known methods based on transient BT signals are experimentally tested by using the provided data to check their solidity. The results show that the created database may be useful for many researchers working on the development of the RFF of BT devices.Article Citation - WoS: 2Citation - Scopus: 1A Close Examination of Ankara's Reinforced Concrete Buildings Designed and Constructed Between 1923 and 1938(Mdpi, 2023) Tunc, Gokhan; Tunc, Tanfer EminThe Republic of Turkey was established in 1923 out of the remains of the Ottoman Empire. Between 1923 and 1938, the Turkish republic underwent fifteen years of rapid expansion and growth, with Ankara as its new capital and Mustafa Kemal Ataturk (1881-1938) as its first president. During this period, reinforced concrete (RC) played a significant role in the construction of Ankara's public-use buildings. This study focuses on 57 of these structures, built either partially, or entirely, out of RC. The buildings are classified with respect to their duration, soil properties, foundation types, structural design details, construction types, materials and overall costs. In order to provide a better picture of the time period in which these buildings were designed and constructed, the technical, financial and political aspects of the projects, and the difficulties and challenges involved in their design and construction, are also discussed. Furthermore, this study outlines the impact of foreign engineers, construction workers, firms and the educational system on the development of civil engineering and use of RC in Turkey.Article Citation - WoS: 5Citation - Scopus: 5A Large-Deformation Gradient Damage Model for Single Crystals Based on Microdamage Theory(Mdpi, 2020) Aslan, Ozgur; Bayraktar, EminThis work aims at the unification of the thermodynamically consistent representation of the micromorphic theory and the microdamage approach for the purpose of modeling crack growth and damage regularization in crystalline solids. In contrast to the thermodynamical representation of the microdamage theory, micromorphic contribution to flow resistance is defined in a dual fashion as energetic and dissipative in character, in order to bring certain clarity and consistency to the modeling aspects. The approach is further extended for large deformations and numerically implemented in a commercial finite element software. Specific numerical model problems are presented in order to demonstrate the ability of the approach to regularize anisotropic damage fields for large deformations and eliminate mesh dependency.Article Citation - WoS: 4Citation - Scopus: 5Space Efficiency in Tall Hotel Towers(Mdpi, 2024) Aslantamer, Ozlem Nur; Ilgin, Huseyin EmreMaximizing spatial utilization within tall buildings stands as a paramount planning consideration for ensuring project feasibility, particularly accentuated ins the context of hotel constructions. To date, no comprehensive study has addressed this issue while considering crucial architectural and structural planning factors. This article fills this gap by using a case study method based on data from 31 contemporary tall hotel towers. The findings revealed several key points: (i) central core typology was mostly utilized; (ii) prismatic buildings were the most prevalent forms; (iii) shear-walled frame systems were predominantly employed; (iv) concrete was the preferred choice for hotel construction; (v) the average space efficiency and the ratio of core area to gross floor area (GFA) averaged 81.2% and 16%, respectively; (vi) the range changed from a minimum of 70% to 4% to a maximum of 94% to 28%; and (vii) space efficiency showed an inverse relationship with the height of the building. It is anticipated that this paper will assist architects and structural engineers as well as builders involved in the planning of hotel developments.Article Citation - WoS: 11Citation - Scopus: 14Sustainability Inclusion in Informatics Curriculum Development(Mdpi, 2020) Mishra, Deepti; Mishra, Alok(1) Background: Presently, sustainability is a crucial issue for human beings due to many disasters owing to climate change. Information Technology (IT) is now part of everyday life in society due to the proliferation of gadgets such as mobile phones, apps, computers, information systems, web-based systems, etc. (2) Methods: The analysis is based on recent ACM/IEEE curriculum guidelines for IT, a rigorous literature review as well as various viewpoints and their relevance for sustainability-oriented curriculum development; it also includes an assessment of key competencies in sustainability for proposed units in the IT curriculum. (3) Results: Sustainability is a critical subject for prospective IT professionals. Therefore, it is imperative to motivate and raise awareness among students and the faculty community regarding sustainability through its inclusion in the Informatics curriculum. This paper focuses on how sustainability can be included in various courses of the Informatics curriculum. It also considers recent ACM/IEEE curriculum guidelines for IT professionals, which assert that IT students should explore IT strategies required for developing a culture of green and sustainable IT. (4) Conclusions: This paper provides guidelines for IT curriculum development by incorporating sustainable elements in courses, so that future IT professionals can learn and practice sustainability in order to develop a sustainable society.Article Citation - WoS: 35Citation - Scopus: 43A New Approach To the Solution of the Fredholm Integral Equation Via a Fixed Point on Extended b-metric Spaces(Mdpi, 2018) Karapinar, Erdal; Kumari, Panda Sumati; Lateef, DurdanaIt is very well known that real-life applications of fixed point theory are restricted with the transformation of the problem in the form of f(x) = x. (1) The Knaster-Tarski fixed point theorem underlies various approaches of checking the correctness of programs. (2) The Brouwer fixed point theorem is used to prove the existence of Nash equilibria in games. (3) Dlala et al. proposed a solution for magnetic field problems via the fixed point approach. In this paper, by obtaining the fixed point results in an extended b-metric space, we are able to consider real-life applications in a very general frame such as a simple and efficient solution for a Fredholm integral equation by using the technique of a fixed point in the consideration of a new abstract space: the extended b-metric space. Moreover, to address conceptual depth within this approach, we supply illustrative examples of usage where necessary.Article Citation - WoS: 6Citation - Scopus: 6Optimized Porous Carbon Particles From Sucrose and Their Polyethyleneimine Modifications for Enhanced Co2 Capture(Mdpi, 2024) Ari, Betul; Inger, Erk; Sunol, Aydin K.; Sahiner, NurettinCarbon dioxide (CO2), one of the primary greenhouse gases, plays a key role in global warming and is one of the culprits in the climate change crisis. Therefore, the use of appropriate CO2 capture and storage technologies is of significant importance for the future of planet Earth due to atmospheric, climate, and environmental concerns. A cleaner and more sustainable approach to CO2 capture and storage using porous materials, membranes, and amine-based sorbents could offer excellent possibilities. Here, sucrose-derived porous carbon particles (PCPs) were synthesized as adsorbents for CO2 capture. Next, these PCPs were modified with branched- and linear-polyethyleneimine (B-PEI and L-PEI) as B-PEI-PCP and L-PEI-PCP, respectively. These PCPs and their PEI-modified forms were then used to prepare metal nanoparticles such as Co, Cu, and Ni in situ as M@PCP and M@L/B-PEI-PCP (M: Ni, Co, and Cu). The presence of PEI on the PCP surface enables new amine functional groups, known for high CO2 capture ability. The presence of metal nanoparticles in the structure may be used as a catalyst to convert the captured CO2 into useful products, e.g., fuels or other chemical compounds, at high temperatures. It was found that B-PEI-PCP has a larger surface area and higher CO2 capture capacity with a surface area of 32.84 m(2)/g and a CO2 capture capacity of 1.05 mmol CO2/g adsorbent compared to L-PEI-PCP. Amongst metal-nanoparticle-embedded PEI-PCPs (M@PEI-PCPs, M: Ni, Co, Cu), Ni@L-PEI-PCP was found to have higher CO2 capture capacity, 0.81 mmol CO2/g adsorbent, and a surface area of 225 m(2)/g. These data are significant as they will steer future studies for the conversion of captured CO2 into useful fuels/chemicals.Article Citation - WoS: 19Citation - Scopus: 24A Novel Hybrid Machine Learning Based System To Classify Shoulder Implant Manufacturers(Mdpi, 2022) Sivari, Esra; Guzel, Mehmet Serdar; Bostanci, Erkan; Mishra, AlokIt is necessary to know the manufacturer and model of a previously implanted shoulder prosthesis before performing Total Shoulder Arthroplasty operations, which may need to be performed repeatedly in accordance with the need for repair or replacement. In cases where the patient's previous records cannot be found, where the records are not clear, or the surgery was conducted abroad, the specialist should identify the implant manufacturer and model during preoperative X-ray controls. In this study, an auxiliary expert system is proposed for classifying manufacturers of shoulder implants on the basis of X-ray images that is automated, objective, and based on hybrid machine learning models. In the proposed system, ten different hybrid models consisting of a combination of deep learning and machine learning algorithms were created and statistically tested. According to the experimental results, an accuracy of 95.07% was achieved using the DenseNet201 + Logistic Regression model, one of the proposed hybrid machine learning models (p < 0.05). The proposed hybrid machine learning algorithms achieve the goal of low cost and high performance compared to other studies in the literature. The results lead the authors to believe that the proposed system could be used in hospitals as an automatic and objective system for assisting orthopedists in the rapid and effective determination of shoulder implant types before performing revision surgery.Article Citation - WoS: 4Citation - Scopus: 4Effects of Cerium Oxide on Kidney and Liver Tissue Damage in an Experimental Myocardial Ischemia-Reperfusion Model of Distant Organ Damage(Mdpi, 2024) Gunes, Isin; Dursun, Ali Dogan; Ozdemir, Cagri; Kucuk, Aysegul; Sezen, Saban Cem; Arslan, Mustafa; Ozer, AbdullahBackground and Objectives: Ischemia-reperfusion (I/R) injury is a process in which impaired perfusion is restored by restoring blood flow and tissue recirculation. Nanomedicine uses cutting-edge technologies that emerge from interdisciplinary influences. In the literature, there are very few in vivo and in vitro studies on how cerium oxide (CeO2) affects systemic anti-inflammatory response and inflammation. Therefore, in our study, we aimed to investigate whether CeO2 administration has a protective effect against myocardial I/R injury in the liver and kidneys. Materials and Methods: Twenty-four rats were randomly divided into four groups after obtaining approval from an ethics committee. A control (group C), cerium oxide (group CO), IR (group IR), and Cerium oxide-IR (CO-IR group) groups were formed. Intraperitoneal CeO2 was administered at a dose of 0.5 mg/kg 30 min before left thoracotomy and left main coronary (LAD) ligation, and myocardial muscle ischemia was induced for 30 min. After LAD ligation was removed, reperfusion was performed for 120 min. All rats were euthanized using ketamine, and blood was collected. Liver and kidney tissue samples were evaluated histopathologically. Serum AST (aspartate aminotransferase), ALT (alanine aminotransaminase), GGT (gamma-glutamyl transferase), glucose, TOS (Total Oxidant Status), and TAS (Total Antioxidant Status) levels were also measured. Results: Necrotic cell and mononuclear cell infiltration in the liver parenchyma of rats in the IR group was observed to be significantly increased compared to the other groups. Hepatocyte degeneration was greater in the IR group compared to groups C and CO. Vascular vacuolization and hypertrophy, tubular degeneration, and necrosis were increased in the kidney tissue of the IR group compared to the other groups. Tubular dilatation was significantly higher in the IR group than in the C and CO groups. TOS was significantly higher in all groups than in the IR group (p < 0.0001, p < 0.0001, and p = 0.006, respectively). However, TAS level was lower in the IR group than in the other groups (p = 0.002, p = 0.020, and p = 0.031, respectively). Renal and liver histopathological findings decreased significantly in the CO-IR group compared to the IR group. A decrease in the TOS level and an increase in the TAS level were found compared to the IR group. The AST, ALT, GGT, and Glucose levels are shown. Conclusions: CeO2 administered before ischemia-reperfusion reduced oxidative stress and ameliorated IR-induced damage in distant organs. We suggest that CeO2 exerts protective effects in the myocardial IR model.
