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Item Investigating Problem-Solving Behaviours Of University Students Through An Eye-Tracking System Using Geogebra In Geometry: A Case Study(Başkent Üniversitesi Eğitim Bilimleri Fakültesi, 2024-08) Turkoglu, Hacer; Yalcinalp, SerpilProblem solving is one of the high-level thinking skills and essential in teaching mathematical concepts and procedures. The eye-tracking method allows educators to see and interpret different problem-solving behaviours of students. The purpose of this study was to investigate the problem-solving behaviours of university students based on eye tracking statistics when faced with a geometry problem, and to explain these behaviours in terms of the students' success and learning styles. The research design was a case study approach that combined quantitative and qualitative data. Eight first-year students from the department of elementary mathematics education in a private University, Turkey, participated in this study. They were asked to solve a specific geometry question using the GeoGebra software. While solving this question, their eye movements were recorded and analysed using an eye-tracking program. Results were analysed to investigate their problem-solving skills and behaviours based on Polya's mathematical problem-solving stages. Results of the study suggest that the effort devoted to the understanding and planning stages of problem-solving are important factors that contribute to success in this case. Results also revealed that participated students with a converger learning style were more successful in each step of the problem-solving process. Additionally, it could be concluded that the input area had only been used by converger students, indicating that they devoted time and effort to creating and trying formulas.Item The Capacitance/Conductance And Surface State Intensity Characteristics Of The Al/(Cmat)/P-Si Structures(Başkent Üniversitesi Fen Edebiyat Fakültesi, 2024-02-01) Cetinkaya, H. G.; Bengi, S.; Sevgili, O.; Altindal, S.To determine the Al/(CMAT)/p-Si structure's admittance analysis, capacitance/conductance versus frequency (C/G-V-f) data was obtained in the 3 kHz-3 MHz and -2/4 V ranges at room temperature. The powder form of CeMgAl11O19: Tb (CMAT) was thermally evaporated onto the front of p-Si wafer at 10-6 Torr as interfacial layer. From the Nicollian and Brews method, voltage-dependent spectra of Rs were derived for various frequencies. The parallel conductance and low-high frequency capacitance (CLF-CHF) techniques, respectively, were used to determine the voltage and frequency dependent spectra of Nss and their lifetime (tau). Surface states (Nss), which are identified by admittance measurements, emerge at the M/S interlayer because of high capacitance and conductance values at low frequencies. This can also be explained by the Nss's ability to track ac signals well at lower frequencies. The normalized parallel conductance versus frequency (Gp/omega-f) plot under various biases shows a peak because of Nss existence. x-ray diffractometer (XRD) was used for structural investigation and the average crystal size (D) of the nanocrystals (CMAT) was found to be less than 0.34 nm by using the Debye-Scherer's equation.Item Predictive Potential Of Pan-Immune-Inflammation Value / Hemoglobin Index As Biomarker For Osteoradionecrosis Risk In Locally Advanced Nasopharyngeal Carcinomas(JOURNAL OF STOMATOLOGY ORAL AND MAXILLOFACIAL SURGERY, 2024-03-27) Yilmaz, Busra; Somay, Efsun; Topkan, Erkan; Pehlivan, Berrin; Besen, Ali Ayberk; Mertsoylu, Huseyin; Selek, UgurObjective: We aimed to investigate whether the Pan-Immune-Inflammation-Value/Hemoglobin (PIV/Hb) index could predict the risk of osteoradionecrosis (ORN) in patients receiving concurrent chemoradiotherapy (CCRT) for locally advanced nasopharyngeal cancer (LA-NPC). Materials and methods: This retrospective analysis included LA-NPC patients who underwent CCRT and preCCRT oral exams at our institution's Departments of Radiation Oncology and Dentistry between January 2010 and December 2022. The relationship between ORN rates and PIV-Hb levels was explored using receiver operating characteristic curve analysis. The primary objective was to establish a correlation between pre-CCRT PIV-Hb levels and ORN rates, while the secondary objective was to identify other risk factors for ORN. Results: Of 249 eligible patients, 21 (8.4 %) were diagnosed with ORN. The optimal pre-CCRT PIV/Hb cutoff was 73.8, which divided patients into two subgroups with distinctive ORN risk estimates: Group 1: PIV/ Hb < 73.8 (N = 206), and Group 2: PIV/Hb >= 73.8 (N = 43). The results of the comparative analysis indicated that the cohort with PIV/Hb >= 73.8 exhibited substantially higher rates of ORN than the PIV/Hb < 73.8 cohort (44.2 % vs. 1.0 %; P < 0.001). The multivariate logistic regression analysis indicated that the pretreatment PIV/ Hb >= 73.8 was independently associated with higher ORN rates (P < 0.001). Conclusion: The results of our current investigation indicate that higher levels of pretreatment PIV/Hb were associated with a significant independent increase in ORN rates in LA-NPC patients who received CCRT. (c) 2024 Elsevier Masson SAS. All rights reserved.Item Experiences Of Physicians On Defensive Medicine: A Qualitative Study From Türkiye(INTERNATIONAL JOURNAL OF HEALTHCARE MANAGEMENT, 2024-02-11) Baskici, Cigdem; Dagdevir, Sude NurThis study aimed to investigate the experiences of physicians regarding defensive medicine (DM) practices. A qualitative study was developed with a descriptive phenomenological approach and the study was conducted in a university hospital in Turkiye. Data were collected between 1 February 2022 and 15 March 2022 via face-to-face, in-depth interviews from 21 participants. Inductive content analysis, which is very suitable for use in health-related research, was used. The analysis of the interview data resulted in 3 main themes, 9 themes, and 24 sub-themes. Main themes described the experiences of physicians: reasons for DM practices, consequences of DM practices, and measures to prevent DM practices. The findings showed the multidimensional nature of DM practices that must be considered in the strategies to be developed to prevent this behavior.Item Investigating Problem-Solving Behaviours Of University Students Through An Eye-Tracking System Using Geogebra In Geometry: A Case Study(EDUCATION AND INFORMATION TECHNOLOGIES, 2024-02-15) Turkoglu, Hacer; Yalcinalp, SerpilProblem solving is one of the high-level thinking skills and essential in teaching mathematical concepts and procedures. The eye-tracking method allows educators to see and interpret different problem-solving behaviours of students. The purpose of this study was to investigate the problem-solving behaviours of university students based on eye tracking statistics when faced with a geometry problem, and to explain these behaviours in terms of the students' success and learning styles. The research design was a case study approach that combined quantitative and qualitative data. Eight first-year students from the department of elementary mathematics education in a private University, Turkey, participated in this study. They were asked to solve a specific geometry question using the GeoGebra software. While solving this question, their eye movements were recorded and analysed using an eye-tracking program. Results were analysed to investigate their problem-solving skills and behaviours based on Polya's mathematical problem-solving stages. Results of the study suggest that the effort devoted to the understanding and planning stages of problem-solving are important factors that contribute to success in this case. Results also revealed that participated students with a converger learning style were more successful in each step of the problem-solving process. Additionally, it could be concluded that the input area had only been used by converger students, indicating that they devoted time and effort to creating and trying formulas.Item The Capacitance/Conductance And Surface State Intensity Characteristics Of The Al/(CMAT)/p-Si Structures(PHYSICA SCRIPTA, 2024-01-24) Cetinkaya, H. G.; Bengi, S.; Sevgili, O.; Altindal, S.To determine the Al/(CMAT)/p-Si structure's admittance analysis, capacitance/conductance versus frequency (C/G-V-f) data was obtained in the 3 kHz-3 MHz and -2/4 V ranges at room temperature. The powder form of CeMgAl11O19: Tb (CMAT) was thermally evaporated onto the front of p-Si wafer at 10-6 Torr as interfacial layer. From the Nicollian and Brews method, voltage-dependent spectra of Rs were derived for various frequencies. The parallel conductance and low-high frequency capacitance (CLF-CHF) techniques, respectively, were used to determine the voltage and frequency dependent spectra of Nss and their lifetime (tau). Surface states (Nss), which are identified by admittance measurements, emerge at the M/S interlayer because of high capacitance and conductance values at low frequencies. This can also be explained by the Nss's ability to track ac signals well at lower frequencies. The normalized parallel conductance versus frequency (Gp/omega-f) plot under various biases shows a peak because of Nss existence. x-ray diffractometer (XRD) was used for structural investigation and the average crystal size (D) of the nanocrystals (CMAT) was found to be less than 0.34 nm by using the Debye-Scherer's equation.Item Material Gradation Effects On Twisting Statics Of Bi-Directional Functionally Graded Micro-Tubes(AIP ADVANCES, 2024-03-04) Aghazadeh, Reza; Rafighi, Mohammad; Kumar, Raman; Al Awadh, MohammedThis study aims to characterize the twisting behavior of bi-directional functionally graded (FG) micro-tubes under torsional loads within the modified couple stress theory framework. The two material properties involved in the torsional static model of FG small-scale tubes, i.e., shear modulus and material length scale parameter, are assumed to possess smooth spatial variations in both radial and axial directions. Through the utilization of Hamilton's principle, the governing equations and boundary conditions are derived, and then, the system of partial differential equations is numerically solved by using the differential quadrature method. A verification study is conducted by comparing limiting cases with the analytical results available in the literature to check the validity of the developed procedures. A detailed study is carried out on the influences of the phase distribution profile and geometric parameters upon twist angles and shear stresses developed in FG micro-tubes undergoing external distributed torques.Item Multifractal Detrended Cross-Correlations between Green Bonds and Commodity Markets: An Exploration of the Complex Connections between Green Finance and Commodities from the Econophysics Perspective(FRACTAL AND FRACTIONAL, 2024-03-08) Acikgoz, Turker; Gokten, Soner; Soylu, Abdullah BugraGreen bonds represent a compelling financial innovation that presents a financial perspective solution to address climate change and promote sustainable development. On the other hand, the recent process of financialisation of commodities disrupts the dynamics of the commodity market, increasing its correlation with financial markets and raising the risks associated with commodities. In this context, understanding the dynamics of the interconnectivity between green bonds and commodity markets is crucial for risk management and portfolio diversification. This study aims to reveal the multifractal cross-correlations between green bonds and commodities by employing methods from statistical physics. We apply multifractal detrended cross-correlation analysis (MFDCCA) to both return and volatility series, demonstrating that green bonds and commodities exhibit multifractal characteristics. The analysis reveals long-range power-law cross-correlations between these two markets. Specifically, volatility cross-correlations persist across various fluctuations, while return series display persistence in small fluctuations and antipersistence in large fluctuations. These findings carry significant practical implications for hedging and risk diversification purposes.Item Exploring the Critical Risk Factors of Public-Private Partnership City Hospital Projects in Turkey(BUILDINGS, 2024-03-14) Dogan Erdem, Tugba; Birgonul, Zeynep; Bilgin, Gozde; Akcay, Emre CanerGovernments face challenges in delivering essential public services due to their limited funds. This has led to an increasing reliance on the Public-Private Partnership (PPP) model, an alternative financing model involving a long-term collaboration between the private and public sectors to provide public services. Turkey, as a developing country facing financial limitations, has embraced the PPP model to address urgent public needs. Over the past decade, the Turkish Government has extensively utilized the PPP model, particularly in executing city hospital projects. However, investors have faced challenges in project execution due to various risk factors. Therefore, the main objective of this study is to explore the critical risk factors associated with PPP city hospital projects in Turkey. In this context, a comprehensive literature review was conducted to identify potential risks related to PPP city hospital projects. A questionnaire survey was implemented to assess the probability of occurrence and the severity of the impact of these risk factors. The collected data underwent analysis to determine the priority of these risk factors. The findings revealed that the top five most critical risk factors in PPP city hospital projects in Turkey are "foreign exchange rate fluctuations", "inflation rate volatility", "high finance costs", "fiscal issues", and "economic crises". Conversely, "unavailability of equipment" was identified as the least significant risk factor. The insights gained from this research can offer valuable guidance for prospective investors interested in participating in PPP city hospital projects in Turkey and other developing countries with similar conditions.Item Effect Of Ultrasonic And Sonic Instrumentation On Shear Bond Strength Of Resin Composite To Enamel: An In Vitro Study(AMERICAN JOURNAL OF DENTISTRY, 2024-04-12) Adiguzel, Ruhsan Muduroglu; Mustafa, Abdelrahman; Oduncuoglu, Bahar Fusun; Colak, Mew Yavuz; Gulsahi, Aye; Arhun, NeslihanPurpose: To assess and compare the effects of sonic and ultrasonic instrumentation on shear bond strength (SBS) and investigate the influence of adhesive system application modes (etch&rinse/self-etch) on SBS. Methods: In this experimental study, 45 extracted sound human molars were selected. Mesial and distal surfaces of the teeth were abraded until 90 smooth enamel surfaces were obtained. Specimens were divided into two groups, with half (N= 45) conditioned in etch&rinse mode and the remaining (N= 45) in self-etch mode using Tetric N Bond Universal. Composite resin discs were produced on these surfaces by filling Teflon molds. All specimens were aged via thermocycling. Each group was further divided into three more groups (n= 15) according to the type of periodontal instrumentation (ultrasonic, sonic or none). SBS values were recorded and analyzed using two-way ANOVA. Fracture sites were examined under a stereomicroscope. Results: The type of periodontal instrumentation had no significant effect on SBS values, whether sonic, ultrasonic or their absence (P= 0.945). The type of adhesive system mode had a significant influence on the shear bond strength values. Etch&rinse groups had significantly higher shear bond strength values than self-etch groups (P< 0.001).