Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Conference Object Citation - WoS: 49Citation - Scopus: 54You May Not Reap What You Sow: How Employees' Moral Awareness Minimizes Ethical Leadership's Positive Impact on Workplace Deviance(Springer, 2017-08-02) Gok, Kubilay; Sumanth, John J.; Bommer, William H.; Demirtas, Ozgur; Arslan, Aykut; Eberhard, Jared; Yigit, AhmetAlthough a growing body of research has shown the positive impact of ethical leadership on workplace deviance, questions remain as to whether its benefits are consistent across all situations. In this investigation, we explore an important boundary condition of ethical leadership by exploring how employees' moral awareness may lessen the need for ethical leadership. Drawing on substitutes for leadership theory, we suggest that when individuals already possess a heightened level of moral awareness, ethical leadership's role in reducing deviant actions may be reduced. However, when individuals lack this strong moral disposition, ethical leadership may be instrumental in inspiring them to reduce their deviant actions. To enhance the external validity and generalizability of our findings, the current research used two large field samples of working professionals in both Turkey and the USA. Results suggest that ethical leadership's positive influence on workplace deviance is dependent upon the individual's moral awareness-helpful for those employees whose moral awareness is low, but not high. Thus, our investigation helps to build theory around the contingencies of ethical leadership and the specific audience for whom it may be more (or less) influential.Article Citation - WoS: 8Citation - Scopus: 8Writing Chemical Patterns Using Electrospun Fibers as Nanoscale Inkpots for Directed Assembly of Colloidal Nanocrystals(Royal Soc Chemistry, 2020) Kiremitler, N. Burak; Torun, Ilker; Altintas, Yemliha; Patarroyo, Javier; Demir, Hilmi Volkan; Puntes, Victor F.; Onses, M. SerdarApplications that range from electronics to biotechnology will greatly benefit from low-cost, scalable and multiplex fabrication of spatially defined arrays of colloidal inorganic nanocrystals. In this work, we present a novel additive patterning approach based on the use of electrospun nanofibers (NFs) as inkpots for end-functional polymers. The localized grafting of end-functional polymers from spatially defined nanofibers results in covalently bound chemical patterns. The main factors that determine the width of the nanopatterns are the diameter of the NF and the extent of spreading during the thermal annealing process. Lowering the surface energy of the substrates via silanization and a proper choice of the grafting conditions enable the fabrication of nanoscale patterns over centimeter length scales. The fabricated patterns of end-grafted polymers serve as the templates for spatially defined assembly of colloidal metal and metal oxide nanocrystals of varying sizes (15 to 100 nm), shapes (spherical, cube, rod), and compositions (Au, Ag, Pt, TiO2), as well as semiconductor quantum dots, including the assembly of semiconductor nanoplatelets.Article Citation - WoS: 11Citation - Scopus: 13Wireless Sensor Network-Based Communication for Cooperative Simultaneous Localization and Mapping(Pergamon-Elsevier Science Ltd, 2015-01) Tuna, Gurkan; Gungor, Vehbi Cagri; Potirakis, Stelios M.; Zeadally, SheraliThis paper presents a novel approach of using a Wireless Sensor Network (WSN) as the communication means for Multi-Robot, Cooperative, Simultaneous Localization and Mapping (CSLAM) applications investigating the associated design challenges and suggesting corresponding solutions. Although the proposed approach brings several benefits including an increased coverage and communication range, self-organization capabilities, quick deployment, and flexible architecture, the realization is interrelated with performance in terms of energy efficiency and reliability. In this respect, the applicability of the WSNs for the presented approach is investigated. Centralized and distributed map merging methods in WSN-based CSLAM are evaluated in detail and the impacts of packet delays and losses on the performance of CSLAM algorithms are shown. Additionally, the involved network congestion and contention dynamics are presented, while the effects of observation range, speed, time intervals between observations, and odometry readings on the SLAM accuracy are shown based on an extensive set of simulation studies. (C) 2014 Elsevier Ltd. All rights reserved.Article Citation - WoS: 19Citation - Scopus: 21Wireless Sensing in Complex Electromagnetic Media: Construction Materials and Structural Monitoring(IEEE-Inst Electrical Electronics Engineers Inc, 2015-10) Ozbey, Burak; Demir, Hilmi Volkan; Kurc, Ozgur; Erturk, Vakur B.; Altintas, AyhanIn this paper, wireless sensing in the presence of complex electromagnetic media created by combinations of reinforcing bars and concrete is investigated. The wireless displacement sensing system, primarily designed for use in structural health monitoring (SHM), is composed of a comb-like nested split-ring resonator (NSRR) probe and a transceiver antenna. Although each complex medium scenario is predicted to have a detrimental effect on sensing in principle, it is demonstrated that the proposed sensor geometry is able to operate fairly well in all scenarios except one. In these scenarios that mimic real-life SHM, it is shown that this sensor exhibits a high displacement resolution of 1 mu m, a good sensitivity of 7 MHz/mm in average, and a high dynamic range extending over 20 mm. For the most disruptive scenario of placing concrete immediately behind NSRR, a solution based on employing a separator behind the probe is proposed to overcome the handicaps introduced by the medium. In order to obtain a one-to-one mapping from the measured frequency shift to the displacement, a numerical fit is proposed and used. The effects of several complex medium scenarios on this fit are discussed. These results indicate that the proposed sensing scheme works well in real-life SHM applications.Article Citation - WoS: 13Citation - Scopus: 13Why Do Muse Stem Cells Present an Enduring Stress Capacity? Hints From a Comparative Proteome Analysis(MDPI, 2021-02-19) Acar, Mustafa B.; Aprile, Domenico; Ayaz-Guner, Serife; Guner, Huseyin; Tez, Coskun; Di Bernardo, Giovanni; Galderisi, UmbertoMuse cells are adult stem cells that are present in the stroma of several organs and possess an enduring capacity to cope with endogenous and exogenous genotoxic stress. In cell therapy, the peculiar biological properties of Muse cells render them a possible natural alternative to mesenchymal stromal cells (MSCs) or to in vitro-generated pluripotent stem cells (iPSCs). Indeed, some studies have proved that Muse cells can survive in adverse microenvironments, such as those present in damaged/injured tissues. We performed an evaluation of Muse cells' proteome under basic conditions and followed oxidative stress treatment in order to identify ontologies, pathways, and networks that can be related to their enduring stress capacity. We executed the same analysis on iPSCs and MSCs, as a comparison. The Muse cells are enriched in several ontologies and pathways, such as endosomal vacuolar trafficking related to stress response, ubiquitin and proteasome degradation, and reactive oxygen scavenging. In Muse cells, the protein-protein interacting network has two key nodes with a high connectivity degree and betweenness: NFKB and CRKL. The protein NFKB is an almost-ubiquitous transcription factor related to many biological processes and can also have a role in protecting cells from apoptosis during exposure to a variety of stressors. CRKL is an adaptor protein and constitutes an integral part of the stress-activated protein kinase (SAPK) pathway. The identified pathways and networks are all involved in the quality control of cell components and may explain the stress resistance of Muse cells.Article Citation - WoS: 6Citation - Scopus: 7Whether and When Did Bitcoin Sentiment Matter for Investors? Before and During the COVID-19 Pandemic(Springer, 2023-12-21) Aysan, Ahmet Faruk; Mugaloglu, Erhan; Polat, Ali Yavuz; Tekin, HasanUsing a wavelet coherence approach, this study investigates the relationship between Bitcoin return and Bitcoin-specific sentiment from January 1, 2016 to June 30, 2021, covering the COVID-19 pandemic period. The results reveal that before the pandemic, sentiment positively drove prices, especially for relatively higher frequencies (2-18 weeks). During the pandemic, the relationship was still positive, but interestingly, the lead-lag relationship disappeared. Employing partial wavelet tools, we factor out the number of COVID-19 cases and deaths and the Equity Market Volatility Infectious Disease Tracker index to observe the direct relationship between a change in sentiment and return. Our results robustly reveal that, before the pandemic, sentiment had a positive effect on return. Although positive coherence still existed during the pandemic, the lead-lag relationship disappeared again. Thus, the causal relationship that states that sentiment leads to return can only be integrated into short-term trading strategies (up to six weeks frequency).Article Citation - WoS: 1When the Railway Reached Istanbul: The Making of Sirkeci Terminus, 1870-1888(Routledge Journals, Taylor & Francis Ltd, 2017-07-16) Tozoglu, AhmetSince its establishment as a capital city, the historical topography of Istanbul has witnessed significant changes, created not only by devastating earthquakes and fires, but also by the implementation of large-scale imperial projects. In the existing literature, the transformation of Istanbul's urban area in the nineteenth century has largely explored the topics of new urban regulations, institutions and their implication after the Tanzimat (reform) decree of 1839. This article aims to explore a lesser-known dimension of nineteenth-century developments of the city: the extension of the railway into the heart of Istanbul's historical peninsula, and the spatial change around the Sirkeci district due to the physical expansion of the terminus area. The construction of a larger terminus (inaugurated in 1890) is relatively well documented in architectural history, yet developments prior to this monumental construction have been less explored so far. Thus, this article also aims to investigate the project's development and implementation phases in the second half of the nineteenth century, when the city witnessed continuous urban reformation processes by focusing on the intertwined relations of different agents in the urban space.Article Citation - WoS: 39Citation - Scopus: 51What Are the Key Success Factors for Strategy Formulation and Implementation? Perspectives of Managers in the Hotel Industry(Elsevier Sci Ltd, 2020-08) Koseoglu, Mehmet Ali; Altin, Mehmet; Chan, Eric; Aladag, Omer FarukThis study investigates how hotel managers describe strategy and identify key success factors for its formulation and implementation. The study analyzes qualitative data collected through semi-structured interviews with property level top managers of hotels in Hong Kong. The findings show that hotel managers prioritize competition analysis and macro-environmental conditions over internal characteristics such as teamwork in strategy formulation. In the implementation phase, however, internal considerations such as employee involvement and strategic consensus are given prominence. This study provides a significant contribution by examining how top level practitioners in the industry interpret success factors in their strategic management efforts, and it highlights a largely neglected area in the hospitality and tourism management literature.Article Citation - WoS: 1Citation - Scopus: 2WSA-Supplements and Proper Classes(MDPI, 2022-08-17) Demirci, Yilmaz Mehmet; Turkmen, ErgulIn this paper, we introduce the concept of wsa-supplements and investigate the objects of the class of short exact sequences determined by wsa-supplement submodules, where a submodule U of a module M is called a wsa-supplement in M if there is a submodule V of M with U + V = M and U boolean AND V is weakly semiartinian. We prove that a module M is weakly semiartinian if and only if every submodule of M is a wsa-supplement in M. We introduce CC-rings as a generalization of C-rings and show that a ring is a right CC-ring if and only if every singular right module has a crumbling submodule. The class of all short exact sequences determined by wsa-supplement submodules is shown to be a proper class which is both injectively and co-injectively generated. We investigate the homological objects of this proper class along with its relation to CC-rings.Article Citation - WoS: 4Citation - Scopus: 4Very Low Density Amorphous Phase of Zircon(Elsevier Science Bv, 2019-06) Bolat, Suleyman; Durandurdu, MuratUsing a reliable ab initio molecular dynamics method, we investigate the rapid solidification of the zircon melt. Accompanied by amorphization, a drastic volume expansion of 27% is perceived. This value is fairly larger than 18% observed in the metamict zircon. Such a large volume swelling leads to a significant decrease in the mean coordination number of Zr atoms, which is about 5.66 and the lowest one reported so far. On the other hand, the volume expansion is found to have almost no impact on the average coordination number of Si atoms i.e., they maintain their tetragonal coordination. As suggested by earlier investigations, the polymerization of SiO4 units is witnessed but our model shows the highest polymerization with respect to the previous simulations. Based on our findings, we propose that our model does not represent the metamict zircon but a very low density amorphous phase of zircon.