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Article Citation - WoS: 17Citation - Scopus: 20In Silico Design of Novel and Highly Selective Lysine-Specific Histone Demethylase Inhibitors(Scientific Technical Research Council Turkey-Tubitak, 2011) Akdoğan, Ebru Demet; Erman, Burak; Yelekçi, KemalHistone lysine-specific demethylase (LSD1) is involved in a wide range of epigenetic processes and plays important roles in gene silencing DNA transcription DNA replication DNA repair and heterochromatin formation. Its active site shows a resemblance to those of 2 homologous enzymes monamine oxidase A and B (MAO-A and MAO-B.) In the present work starting from suitable scaffolds and generating thousands of structures from them 10 potential inhibitors were obtained with structural and physicochemical properties selectively suitable for inhibiting LSD1. iLib Diverse software was used to generate the diverse structures and 3 docking tools CDOCKER GOLD and AutoDock were used to find the most probable potential inhibitor based on its binding affinity. The dispositions of the candidate molecules within the organism were checked by ADMET_PSA_2D (polar surface area) versus ADMET_AlogP98 (the logarithm of the partition coefficient between n-octanol and water) and their suitability is discussed. The LSD1 inhibition activities of the candidates were compared with the properties of trans-2-phenylcyclopropylamine (tranylcypromine) and 2-(4-methoxy-phenyl) cyclopropylamine which are the 2 known inhibitors of LSD1.Article Citation - WoS: 145Citation - Scopus: 145Psychological Correlates of Covid-19 Conspiracy Beliefs and Preventive Measures: Evidence From Turkey(Springer, 2020) Alper, Sinan; Bayrak, Fatih; Yılmaz, OnurcanCOVID-19 pandemic has led to popular conspiracy theories regarding its origins and widespread concern over the level of compliance with preventive measures. In the current preregistered research, we recruited 1088 Turkish participants and investigated (a) individual differences associated with COVID-19 conspiracy beliefs; (2) whether such conspiracy beliefs are related to the level of preventive measures; and (3) other individual differences that might be related to the preventive measures. Higher faith in intuition, uncertainty avoidance, impulsivity, generic conspiracy beliefs, religiosity, and right-wing ideology, and a lower level of cognitive reflection were associated with a higher level of belief in COVID-19 conspiracy theories. There was no association between COVID-19 conspiracy beliefs and preventive measures while perceived risk was positively and impulsivity negatively correlated with preventive measures. We discuss the implications and directions for future research.Article Citation - WoS: 21Citation - Scopus: 22Design of Practical Broadband Matching Networks With Lumped Elements(IEEE-INST Electrical Electronics Engineers Inc, 2013) Şengül, Metin Y.It is always preferable to use commercially available software tools to design broadband matching networks for microwave communication systems. However for these tools the matching network topology and element values must be selected properly. Therefore in this paper a practical method is presented to generate matching networks with good initial element values. Eventually the performance of the designed matching network is optimized by employing the commercially available computer-aided design (CAD) tools. An example is given to illustrate the utilization of the proposed method. It is shown that the proposed method provides very good initials for CAD tools.Conference Object Management Information Systems: the Virtual Team Scorecard (vts)(2013) Oberer, Birgit; Erkollar, AlptekinOrganizations resisting changes are missing opportunities to grow or to become or remain competitive. Management Information Systems (MIS) used as decision support systems may support organizations in making use of changes in environmental conditions. Nevertheless innovative structures are needed to motivate organizations contributing in change projects. Tn this study a virtual team scorecard which can be used as a management information system enabling requirements analyses for managing virtual teams in organizations and in virtual teams with members of different organizations was developed in two different versions: (a) an intemal VTS and (b) an inter-organizational VTS. The results revealed that the developed virtual team scorecard covers all the main strategic factors from a management perspective and in particular relies on the qualitative factors of the team determines the quality and group dynamics deficits of a team and may provide clues for knowing which factors should receive special attention. Furthermore the developed scorecard can be used for inter-organizational teams and any kind of structured co-operation between organizations.Article Citation - WoS: 21Citation - Scopus: 20"it Was as If Society Didn't Want a Woman To Get an Abortion": a Qualitative Study in Istanbul Turkey(Elsevier Science Inc, 2017) MacFarlane, Katrina A.; O'Neil, Mary Lou; Tekdemir, Deniz; Foster, Angel M.Introduction: In 1983 abortion without restriction as to reason was legalized in Turkey. However at an international conference in 2012 the Prime Minister condemned abortion and announced his intent to draft restrictive abortion legislation. As a result of public outcry and protests the law was not enacted but media reports suggest that barriers to abortion access have since worsened. Objectives: We aimed to conduct a qualitative study exploring women's recent abortion experiences in Istanbul Turkey. Study design: In 2015 we conducted 14 semi-structured in-depth interviews with women aged 18 or older who had obtained abortion care in Istanbul on/after January 1 2009. We employed a multimodal recruitment strategy and analyzed these interviews for content and themes using deductive and inductive techniques. Results: Women reported on a total of 19 abortions. Although abortion care is available in private facilities only one public hospital provides abortion services without restriction as to reason. Women who had multiple abortions in different facility types described quality of care more positively in the private sector. Unmarried women considered their marital status when making the decision to seek an abortion and reported challenges obtaining comprehensive sexual and reproductive health services. All participants were familiar with the Turkish government's antiabortion discourse and believed that this was reflective of an overarching desire to restrict women's rights. Conclusion: Public abortion services in Istanbul are currently limited and private abortion services are accessible but relatively expensive to obtain. Recent antiabortion political rhetoric appears to have negatively impacted access and service quality. Implications: This is the first qualitative study exploring women's experiences obtaining abortion services in Turkey since the proposed abortion restriction in 2012. Further research exploring the experiences of unmarried women and abortion accessibility in other regions of the country is warranted. (C) 2017 Elsevier Inc. All rights reserved.Article Citation - WoS: 13Citation - Scopus: 14Energy-Saving Behavior of Turkish Women: a Consumer Survey on the Use of Home Appliances(Sage Publications Ltd, 2017) Ucal, Meltem ŞengünThis paper focuses on energy-related attitudes and behaviors of Turkish women who are the main users of electrical home appliances responsible for most household energy consumption. Answers from 1323 female respondents surveyed through a unique questionnaire formed the dataset. The results from analysis of variance show that education has a significant effect on the relationship between energy saving and awareness and attitudes about climate change. Significant differences also exist between education level groups in terms of knowledge of the classification of energy-saving electrical home appliances. Responses to questions related to energy-saving purchasing behaviors are consistently higher for knowledgeable respondents. The paper then uses factor analysis and ordinal logit models to reveal interactions between energy-saving behavior regarding electrical home appliances and several factors namely awareness sensitivity essentials and receptiveness. The identification of these factors can provide useful insights for policy makers that enable them to construct energy-saving policies specifically tailored toward women.Article Citation - WoS: 9Citation - Scopus: 8Daily and Intraday Herding Within Different Types of Investors in Borsa Istanbul(Routledge Journals, Taylor & Francis Ltd, 2019) Dalgıç, Nihan; Ekinci, Cumhur; Ersan, OğuzThis paper aims to explore the daily and intraday herd behavior of various investor groups trading in an emerging equity market, Borsa Istanbul (BIST). We analyze a one-year tick-by-tick order and trade data of BIST 100 Index stocks and document differences in herding behavior of investor groups considering market capitalization, market conditions, and announcements as well as daily and intraday periodicities. We find that nonprofessional investors (brokerage houses and domestic funds) tend to herd on large (small) stocks; their herding behavior mostly exhibits a U shape (an inverse U shape) during the day. All types of investors tend to herd in down markets on a daily basis while this behavior disappears, even inverts intraday.Article Citation - WoS: 7Citation - Scopus: 6Investigation of Pst-Mwcnt Concentration on Epoxyacrylate Photopolymerization and Conductivity of Polymer Films(Elsevier Science SA, 2013) Doğruyol, Zekeriya; Temel, Gökhan; Doğruyol, Sevnur Keskin; Pekcan, Önder; Arsu, NergisPhotopolymerization kinetics and conductivity changes of epoxyacrylate composites for various loading modified PSt-MWCNT weight fractions changing from 0.0025 to 0.2 wt.% were evaluated by performing photo differential scanning calorimetry (photo-DSC) and four point conductivity measurements. 0.2% PSt-MWCNT additive polymeric films had their electrical conductivity boosted by 6% more than non-additive polymeric films. (C) 2012 Elsevier B.V. All rights reserved.Conference Object Citation - Scopus: 1Ieee 802.15.4a Based Ultra Wideband Systems for Coexistence With Primary Users(IEEE, 2015) Fındıklı, Çağlar; Erküçük, Serhat; Çelebi, Mehmet ErtuğrulPeaceful coexistence is a major implementation issue for both cognitive radios and ultra wideband (UWB) systems. Accordingly the UWB impulse radio (UWB-IR) based Wireless Personal Area Network (WPAN) standard IEEE 802.15.4a has suggested using linear combination of pulses to limit interference to coexisting primary systems. In this paper motivated by implementing the IEEE 802.15.4a based UWB-IR systems for peaceful coexistence we consider the implementation of linear combination of pulses as suggested by the standard. Accordingly we (I) design linearly combined pulses that conform to the standard requirements and (ii) study the UWB-IR system performance in the presence of orthogonal frequency division multiplexing (OFDM) based wideband primary systems with various bandwidths and subcarriers. The study shows that the UWB-IR system performance can be significantly improved by selecting suitable pulses for transmission and employing appropriate filtering techniques at the receiver when the primary system is active. The results are important for the practical implementation of IEEE 802.15.4a based UWB systems coexisting with licensed systems.Article Citation - WoS: 8Citation - Scopus: 11Does mood affect institutional herding?(Elsevier, 2020) Gavriilidis, Konstantinos; Kallinterakis, Vasileios; Öztürkkal, BelmaDrawing on a unique data set of daily portfolio holdings for Turkish mutual funds we investigate the relationship between mood and institutional herding on the premises of various established mood proxies (weekend effect; holiday effect; Ramadan; sunshine). Results indicate that fund managers in Turkey herd significantly, with their herding growing in magnitude as the number of active funds per stock rises and appearing stronger on the buy-than the sell-side. Although the relationship of mood with institutional herding occasionally assumes the correct sign as per theoretical expectations, institutional herding is found to be insignificantly different across various mood states, thus denoting that mood does not impact the propensity of fund managers to herd. (C) 2020 Elsevier B.V. All rights reserved.Article Citation - WoS: 37Citation - Scopus: 40Joint Optimization of Wireless Network Energy Consumption and Control System Performance in Wireless Networked Control Systems(IEEE-INST Electrical Electronics Engineers Inc, 2017) Şadi, Yalçın; Ergen, Sinem ColeriCommunication system design for wireless networked control systems requires satisfying the high reliability and strict delay constraints of control systems for guaranteed stability with the limited battery resources of sensor nodes despite the wireless networking induced non-idealities. These include non-zero packet error probability caused by the unreliability of wireless transmissions and non-zero delay resulting from packet transmission and shared wireless medium. In this paper we study the joint optimization of control and communication systems incorporating their efficient abstractions practically used in real-world scenarios. The proposed framework allows including any non-decreasing function of the power consumption of the nodes as the objective any modulation scheme and any scheduling algorithm. We first introduce an exact solution method based on the analysis of the optimality conditions and smart enumeration techniques. Then we propose two polynomial-time heuristic algorithms based on intelligent search space reduction and smart searching techniques. Extensive simulations demonstrate that the proposed algorithms perform very close to optimal and much better than previous algorithms at much smaller runtime for various scenarios.Article Citation - WoS: 13Citation - Scopus: 15An Integrated Fuzzy Best-Worst Method for Evaluation of Hotel Website and Digital Solutions Provider Firms(Hindawi Limited, 2020) Samanlıoğlu, Funda; Burnaz, Ayşe Nur; Diş, Berke; Tabaş, Mehmet Doğukan; Adıgüzel, MehmetIn todays world where technology is rapidly evolving, hotels need to be the best in all conditions to be one step ahead of other competitors. Digital marketing and hotel website solutions play a lead role in this competition. Therefore, hotel websites need to be innovative, user-friendly, and descriptive. The main purpose of the study is to evaluate and rank potential hotel websites and digital solutions provider firms. Since there are various potentially competing quantitative and qualitative criteria to take into consideration in the decision-making process, a multicriteria decision-making (MCDM) method is needed. As the MCDM method, fuzzy best-worst method (FBWM) is integrated with the Fuzzy Technique for Order Preference by Similarity to Ideal Solution (F-TOPSIS). In this integration, FBWM is applied to determine fuzzy evaluation criteria weights and then F-TOPSIS is implemented to rank alternatives utilizing the obtained fuzzy weights. A case study is presented, where 4 alternative hotel websites and digital solutions provider firms for Paloma Hotels in Turkey are evaluated based on 9 criteria by 3 hotel managers.Article Citation - WoS: 15Citation - Scopus: 15Rapidly Time-Varying Channel Estimation for Full-Duplex Amplify-And One-Way Relay Networks(IEEE-INST Electrical Electronics Engineers Inc, 2018) Şenol, Habib; Li, Xiaofeng; Tepedelenlioglu, CihanEstimation of both cascaded and residual self-interference (RSI) channels and a new training frame structure are considered for full-duplex (FD) amplify-and-forward (AF) one-way relay networks with rapidly time-varying individual channels. To estimate the RSI and the rapidly time-varying cascaded channels we propose a new training frame structure in which orthogonal training blocks are sent by the source node and delivered to the destination over an FD-AF relay. Exploiting the orthogonality of the training blocks we obtain two decoupled training signal models for the estimation of the RSI and the cascaded channels. We apply linear minimum mean square error (MMSE) based estimators to the cascaded channel as well as RSI channel. In order to investigate the mean square error (MSE) performance of the system we also derive the Bayesian Cramer-Rao lower bound. As another performance benchmark we also assess the symbol error rate (SER) performances corresponding to the estimated and the perfect channel state information available at the receiver side. Computer simulations exhibit the proposed training frame structure and the linear MMSE estimator MSE and SER performances are shown.Article Citation - WoS: 21Citation - Scopus: 27Vacillation in Turkey's Popular Global Tv Exports: Toward a More Complex Understanding of Distribution(USC Annenberg Press, 2016) Alankuş, Sevda; Yanardağoğlu, EylemAudience demand for Turkey's TV series has increased their strength in the regional market and beyond. By mid-2014 more than 70 Turkish TV dramas reached audiences in 75 countries. Some experts have characterized this as neo-Ottoman cool, referring to Turkey's growing "soft power" role in successfully combining Islam with democracy. However, survey data from 16 Arab countries, previous audience studies, and our in-depth interviews with Istanbul-based producers and distributors refute this. Neo-Ottoman cool does not register the full dynamics of contingent relations between economy, politics, ideology, and media flows. Our research underscores the region's glocal flexibility and the market articulations overarching Turkey's soft power ambitions, how the drama genre attracts women cross-culturally, and the limits of notions of cultural proximity.Article Citation - WoS: 1A Survey Analysis on the Investment Attitudes of Individual Investors(Bilgesel Yayincilik San & Tic Ltd, 2013) Öztürkkal, BelmaThis study aims to analyze determinants of trading behavior of individual investors where a survey of 55 questions on 85 people is used. The survey is composed of four parts: demographic properties perceived emotions investment preferences portfolio diversification. The findings show that investors are subject to home bias and the surveyed investors prefer to invest in local equity market. The findings show that older investors have less investment confidence and more diversification where number of different stocks and HHI (Hezfindahl-Hirshman Index) are used as two diversification measures in the analysis. The OLS regression and logit response results prove that male investors trade more and when the investor's equity portion of the total portfolios increases the number of trades also increases. The self-reported investment confidence level and greed have positive effect on diversification. Hence diversification level increases with the investor's equity portion of their total portfolios. The findings suggest that male investors on the average are more confident than females in their investment decisions and males who are more confident have better portfolio diversification choices.Article Citation - WoS: 1Citation - Scopus: 1The Role of Pyranine in Characterization of Paam-Kappa C Composites by Using Fluorescence Technique(Springer/Plenum Publishers, 2011) Evingür, Gülşen Akın; Pekcan, ÖnderPolyacrylamide (PAAm) doped by kappa-carrageenan (kappa C) gels were prepared with various amounts of kappa C varying in the range between 0 wt.% and 3 wt.%. Steady-state fluorescence (SSF) technique was employed for studying sol-gel transition and swelling of PAAm-kappa C composite gels which were prepared by free-radical crosslinking copolymerization. Pyranine was introduced as a fluorescence probe. Pyranine molecules start to bind to acrylamide polymer chains upon the initiation of the polymerization thus the spectra of the bonded pyranines shift to the shorter wavelengths. Fluorescence spectra from the bonded pyranines allow one to monitor the sol-gel transition and to test the universality of the sol-gel transition as a function of some kinetic parameters like polymer concentration. Observations around the gel point t (c) for PAAm-kappa C composite gels showed that the gel fraction exponent beta obeyed the percolation result for low kappa C (< 2.0 wt. %) however classical results were produced at higher kappa C (> 2.0 wt.%). On the other hand fluorescence intensity of pyranine was measured during in situ swelling process at various amounts of kappa C and it was observed that fluorescence intensity values decreased as swelling is proceeded. Li-Tanaka equation was used to determine the swelling time constants tau and cooperative diffusion coefficients D.Article Citation - WoS: 25Citation - Scopus: 28Low-Complexity Map-Based Successive Data Detection for Coded Ofdm Systems Over Highly Mobile Wireless Channels(IEEE-INST Electrical Electronics Engineers Inc, 2011) Panayırcı, Erdal; Dogan, Hakan; Poor, H. VincentThis paper is concerned with the challenging and timely problem of data detection for coded orthogonal frequency-division multiplexing (OFDM) systems in the presence of frequency-selective and very rapidly time varying channels. New low-complexity maximum a posteriori probability (MAP) data detection algorithms are proposed based on sequential detection with optimal ordering (SDOO) and sequential detection with successive cancellation (SDSC). The received signal vector is optimally decomposed into reduced dimensional subobservations by exploiting the banded structure of the frequency-domain channel matrix whose bandwidth is a parameter to be adjusted according to the speed of the mobile terminal. The data symbols are then detected by the proposed algorithms in a computationally efficient way by means of the Markov chain Monte Carlo (MCMC) technique with Gibbs sampling. The impact of the imperfect channel state information (CSI) on the bit error rate (BER) performance of these algorithms is investigated analytically and by computer simulations. A detailed computational complexity investigation and simulation results indicate that particularly the algorithm based on SDSC has significant performance and complexity advantages and is very robust against channel estimation errors compared with existing suboptimal detection and equalization algorithms proposed earlier in the literature.Book Part Citation - WoS: 4Conductivity Percolation of Carbon Nanotubes in Polyacrylamide Gels(Intech Europe, 2011) Pekcan, Önder; Evingür, Gülşen Akın[Abstract Not Available]Article The Relationship Between Firm Size and Export Sales: Sector or Size What Matters?(Physica-Verlag, 2017) Berk, Niyazi; Öztürkkal, BelmaThis paper examines the performance of export focused companies listed on the Borsa Istanbul trading in the emerging market of Turkey. Using the panel data of stock market prices (1995–2011) we study the performance of companies in different sectors and their return performance in the volatile exchange rate environment and devaluation periods of 1996 1997 1998 1999 2001 and 2008. The paper investigates sales market capitalization or asset performances’ statistical significance level with regard to these companies’ export level. We review the performance of these operational measures in an environment of changing foreign exchange rates. Regression analysis is used to measure the effects of currency devaluation on the companies analyzed. Finally the study analyzes the export sales of companies by sector following a period of sharp devaluation. © Springer International Publishing AG 2017.Book Part Citation - WoS: 3Energy Security in South East Europe(Palgrave, 2013) Cehulic, Lidija; Kuznetsov, Alexey V.; Çelikpala, Mitat; Gleason, Gregory[Abstract Not Available]
