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Article Web Server-Based Structure Prediction as a Supplementary Tool for Basic and Acidic Fgf Secondary Structure Analysis Using Ftir Spectroscopy and a Case Study Comparing Curve-Fit With the Model-Based Structure Inspection of the Ftir Data(DergiPark, 2023) Korkmaz,F.; Mollaoglu,A.; Adiguzel,Y.Fourier Transform Infrared (FTIR) spectroscopy can provide relative proportion of secondary structure elements in a protein. However, extracting this information from the Amide I band area of an FTIR spectrum is difficult. In addition to experimental methods, several protein secondary structure prediction algorithms serving on the Web can be used as supplementary tools requiring only protein amino acid sequences as inputs. In addition, web-server based docking tools can provide structure information when proteins are mixed and potentially interacting. Accordingly, we aimed to utilize web-server based structure predictors in fibroblast growth factor (FGF) protein structure determination through the FTIR data. Seven such predictors were selected and tested on basic FGF (bFGF) protein, to predict FGF secondary structure. Results were compared to available structure-files deposited in the Protein Data Bank (PDB). Then, FTIR spectra of bFGF and the acidic form of the protein with 50 folds more bovine serum albumin as carrier protein (1FGFA/50BSA) were collected. Optimized Amide I curve-fit parameters of bFGF with low (<5) root mean square deviation (RMSD) in the PDB data and the predictions were obtained. Those parameters were applied in curve-fitting of 1FGFA/50BSA data. Secondary structure was inspected also through applying models derived from the previously established methods. Results of model-based secondary structure estimation from FTIR data were compared with secondary structure calculated as 1 part contribution from 1FGFA/1BSA complex and 49 parts contribution from BSA. Complex structure was obtained through docking. RMSD in the PDB data and the predictions were respectively 3.05 and 2.39 with the optimized parameters. Those parameters did not work well for the 1FGFA/50BSA data. Models are better in this case, wherein one model (Model-1’) with the lowest average RMSD has 8.38 RMSD in the bFGF and 4.78 RMSD in the 1FGFA/50BSA structures. Model-based secondary structure predictions are better for determining bFGF and 1FGFA/50BSA secondary structures through the curve-fit approach that we followed, under non-optimal conditions like protein/BSA mixtures. Web servers can assist experimental studies investigating structures with unknown structures. Any web-based structure prediction supporting the experimental results would be enforcing the findings, but the unsupported results would not necessarily falsify the experimental data. © (2023), (DergiPark). All rights reserved.Article Citation - Scopus: 17Exporting by Migrants and Indigenous Entrepreneurs: Contingent on Gender and Education(Inderscience Publishers, 2016) Ashourizadeh,S.; Schøtt,T.; Şengüler,E.P.; Wang,Y.Migrants may become entrepreneurs in their host countries. They may utilise their dual embeddedness in both the home country and the host country, and also use transnational links to gain a competitive advantage in exporting compared to indigenous entrepreneurs. Migrant entrepreneurs' advantage may, however, be contingent on attributes such as gender and education, especially among the first generation of migrants, in that being male and educated is more advantageous for migrants than for indigenous entrepreneurs. A representative sample of 50,371 entrepreneurs establishing or operating enterprises around the world was surveyed in the Global Entrepreneurship Monitor, which reports on migration and exporting. Hierarchical linear modelling shows that migrant entrepreneurs export more than indigenous entrepreneurs, especially in the first generation, and especially among educated and male migrants. These findings can be generalised to migrant and indigenous entrepreneurs worldwide to enhance knowledge about the entrepreneurial benefits of migration, albeit contingent on gender and education. Copyright © 2016 Inderscience Enterprises Ltd.Conference Object Üniversite Yazilim Mühendisligi Programlari Müfredatinin Swebok Kilavuzu Kullanilarak Degerlendirme ve İyilestirilmesi: Türkiye'de Bir Vaka Çalismasi(CEUR-WS, 2015) Garousi,V.; Mishra,A.; Yazici,A.[No abstract available]Conference Object Citation - Scopus: 1Online Shopping Web Sites' Perceived Usability: a Case Study With Turkish Shopping Related Web Sites(Springer international Publishing Ag, 2021) Demirci, H. MerveUsing an online shopping website could be considered preferable to shopping from a crowded shop where one may interact with other people. The underlying reasons for this preference related to the psychology of the people; whether they are introverted or shy, or while online shopping, people may feel freer than being in a physical shop with lots of people, which may lead them to feel irritated [1]. On the other hand, the reason may relate to the websites' design and usability to make them a better option. This study aims to analyze the shopping sites' interface designs' perceived usability on users in Turkey and the relation of the websites' measured usability with the help of CogTool to make a comprehension between the findings. To reach this aim, first of all, a survey had conducted through an e-mail to choose the most preferred online shopping sites with 25 women. Afterward, one task had been decided; buying the same shoe for participants to complete to measure decided websites' usability. The usability test had been done with CogTool to the chosen websites, and a user test had been done with the ten female users out of 25 as a continuation of the first phase of the study. The study's findings show the underlying reasons for the preferences and the overlapping values between usability and user tests.Article Representations of Africa in Ben Okri's and Alexander Mccall Smith's Works(Ovidius University, 2023) Aksoy,N.B.This presentation explores the representation of Africa in different novels by two different writers. The novels belong to late 20th and early 21st-century British fiction set in Africa. The two writers have different backgrounds in many ways except for their engagement, love and complicated relationship with the African continent. I argue that the representation by these writers reveals the meaning and significance of Africa in a postcolonial context as a space of nostalgia, loss, and eventually, hope in contemporary British fiction. © 2023 Ovidius University. All rights reserved.Article Citation - WoS: 5Measurement of Solar Radiation in Ankara, Turkey(Turkish Soc thermal Sciences Technology, 2013) Caglar, Ahmet; Yamali, Cemil; Baker, Derek K.; Kaftanoglu, BilginThe solar energy potential of Ankara, Turkey, (39.89 degrees N, 32.78 degrees E) has been investigated using the measurements of global and beam radiation over the period May 2008 to May 2009. Surface air temperature was also measured and variation in clearness index evaluated over this period. Global and beam radiations have been analyzed using hourly, daily and monthly averages obtained from 1-minute averages of recorded data. Results show that annual average daily global and beam radiations were 17.04 and 15.72 MJ/m(2)/day, respectively, for this period. The results are compared with the data available for several other cities in Turkey. The study shows that Ankara has a large solar potential. The consistency of these data with that from the State Meteorological Service (SMS) weather station in Ankara was analyzed. Significant differences between these 2 stations were found and are attributed to measurement error at the SMS station. New radiation-measurement stations should be established to create a better national radiation database for Turkey.Article Evaluating Effectiveness of Led\rand Oled Lights on User Visual\rcomfort and Reading Performance(2021) Avcı, Ayşe Nihan; Memikoğlu, İpekIn interior architecture, one of the main purposes of light is to create comfort-\rable and functional spaces according to user needs. Light provides individuals to\runderstand, get information for visual tasks and it affects how they experience\rand behave in the environment. Desired illuminance levels are required for visual\rcomfort and task efficiency. This study analyzes the effects of different illuminance\rlevels of light emitting diode (LED) and organic light emitting diodie (OLED)\rlights on user visual comfort and reading performance. An experiment was con-\rducted with eighty interior architecture students at Çankaya University. Six light-\ring scenarios were created with LED and OLED lighting sources that assessed\rsix visual comfort criteria. The experimental setting consisted of three different\rilluminance levels, as 200, 500 and 800 lx. The results revealed that different illu-\rminance levels were found more comfortable for different visual comfort criteria,\rbut the illuminance level of 500 lx was visually more comfortable than the other il-\rluminance levels. The illuminance level of LED 200 lx was visually more comfort-\rable than LED 800 lx. OLED light was found visually more comfortable than LED\rlight. In addition, participants read slower under the illuminance level of LED\r200 lx. It was concluded that illuminance levels of light effect user’s visual comfort\rand reading performance. This study provides a basis to recommend the preferred\rilluminance level for LED and OLED light during a reading performance.Article Citation - WoS: 5Citation - Scopus: 5Automorphisms of the mapping class group of a nonorientable surface(Springer, 2017) Atalan, Ferihe; Szepietowski, BlazejLet S be a nonorientable surface of genus g >= 5 with n >= 0 punctures, and Mod(S) its mapping class group. We define the complexity of S to be the maximum rank of a free abelian subgroup of Mod(S). Suppose that S-1 and S-2 are two such surfaces of the same complexity. We prove that every isomorphism Mod(S-1) -> Mod(S-2) is induced by a diffeomorphism S-1 -> S-2. This is an analogue of Ivanov's theorem on automorphisms of the mapping class groups of an orientable surface, and also an extension and improvement of the first author's previous result.Article Citation - WoS: 1A NEW FORMULATION FOR THE BOUNDARY ELEMENT ANALYSIS OF HEAT CONDUCTION PROBLEMS WITH NONLINEAR BOUNDARY CONDITIONS(Turkish Soc thermal Sciences Technology, 2019) Baranoglu, BesimAn effective numerical method based on the boundary element formulation is presented to solve heat conduction equations which are governed by the Fourier equation, with nonlinear boundary conditions on one or more sections of the prescribed boundary. The solution involves the manipulation of the system matrices of the boundary element method and obtaining a smaller ranked matrix equation in which the unknown is only the temperature difference over the nonlinear boundary condition region. This way, the iterations to deal with the nonlinear conditions are performed faster. After finding the solution over the nonlinear boundary condition region, the solution over the entire boundary is obtained as a post-process through a prescribed relation. An example with a proven exact solution is employed to assess the results.Article Citation - Scopus: 5The Relationships Between Human Values, Absenteeism Attitudes and Reasons;(Hacettepe University, 2016) Demirutku,K.; Tekinay,S.The present study was conducted to investigate the relationships between human values, absenteeism attitudes, and absenteeism reasons. A correlation study was carried out with 180 students who were enrolled in different programs in a private university located in Ankara. Value orientations of the participants was measured by using Portrait Values Questionnaire (Schwartz et al., 2012) and absenteeism attitudes were measured by using semantic differential scales. In addition, students reported the frequencies of not going to the campus in class-days, and not attending the classes despite being in the campus with various reasons on the scales developed by referring to the relevant literature to be used in the present study. Correlation analyses revealed that the importance of hedonism and stimulation values was positively, whereas the importance of self-direction and conformity values was negatively correlated with absenteeism attitudes and reasons. It was proposed that absenteeism attitudes and reasons might have the function of expressing different values. The results were discussed by taking into account the measurement- and sample-related limitations of the study, and corresponding suggestions for future research were presented. © 2016, Hacettepe University. All rights reserved.
