Fakülteler / Faculties
Permanent URI for this communityhttps://hdl.handle.net/11727/1395
Browse
3677 results
Search Results
Item The Evaluation of Enamel Matrix Derivative on the Bone Regenerative Potential of the Dental Implant with the Transcrestal Sinus Floor Elevation Approach: A Randomized, Parallel CBCT Study(Başkent Üniversitesi Diş Hekimliği Fakültesi, 2024-09-23) Ozbay, Deniz; Tunc, Samet; Corekci, Ahu Uraz; Ayyildiz, Berceste Guler; Cula, SerpilPurpose: To evaluate the clinical and radiographic results of simultaneous implant placement using transcrestal sinus floor elevation (TSFE) with and without enamel matrix derivative (EMD) application. Materials and Methods: Twenty-four patients were randomly assigned into two groups: The EMD+TSFE group (n = 13 patients, 20 implants) received TSFE with EMD application, and the TSFE group (n = 11 patients, 20 implants) received TSFE without EMD application. The patients were recalled at 3 (T3) and 12 (T12) months postsurgery. The residual bone height (RBH), implant protrusion length (IPL), peri-implant sinus bone level (SBL), endo-sinus bone gain (ESBG), and implant stability (ISQ) were measured. Multivariate regressions were performed for the groups. Results: At T3, the ESBG was 3.72 +/- 0.85 mm in the EMD+TSFE group and 3.10 +/- 0.05 mm in the TSFE group, and there were statistically significant differences (P P < .05). However, there were no statistically significant differences in ESBG at T12 between the groups (P P > .05). ISQ values did not show a statistical difference between the groups at T1 and T3, but at T3 in the TSFE+EMD group, there was a statistical increase in the intragroup evaluation compared to the TSFE group. Conclusions: The use of EMD in TSFE procedures is effective in new bone formation at the apical part of the implant during the early healing period, but in the long term, no significant difference was shown between cases in which EMD was or was not used in terms of new bone formation and primary and secondary stabilization. Int J Oral Maxillofac Implants 2024;39:615-624. doi: 10.11607/jomi.10506Item Developing Countries' Deadlock: What Does the Thirlwall's Law Offer Us?(Başkent Üniversitesi İktisadi İdari Bilimler Fakültesi, 2024-10-17) Can, ZiyaThis study aims to discuss potential alternatives for economic development in developing countries, with contributions from the theoretical background of Thirlwall's law. Developing countries' foreign trade constraints will be highlighted, followed by a comparison of T & uuml;rkiye 's past growth performance with results obtained from Thirlwall's Law equations using balance of payments data. T & uuml;rkiye 's actual growth rates closely resemble the growth forecast of Thirlwall's model, which indicates that post-Keynesian approaches are worth considering to alter the current situation. While providing a perfect solution that could reverse everything for developing countries may be a distant goal, this study aspires to foster a mindset capable of changing the course of events.Item Evaluation Of The Efficacy Of Adjuvant Radiotherapy Versus Chemoradiotherapy In Patients With Salivary Gland Tumors(Başkent Üniversitesi Diş Hekimliği Fakültesi, 2024-12-25) Topkan, Erkan; Somay, EfsunItem Fluorimetric Methods For Determination Of Aluminum In Water Resources Utilizing Newly Synthesized N,N'-bis (2,5-dihydroxybenzylidene)-4,4′-Diamino Diphenyl Ether(Başkent Üniversitesi Eczacılık Fakültesi, 2024-07-16) Tatli, Havva Nur; Gunduz, S. Beniz; Sahin, Mustafa; Altuner, Elif Esra; Dar, Umar AliIndustrial waste contaimnation of water sources is a serious environmental problem. As a result, it's critical to identify metallic contamination in water with precision, sensitivity, and accuracy. In acetonitrile, the fluorimetric parameters of N,N-'bis(2,5-dihydroxybenzylidene)-4,4 '-diamino diphenyl ether (DHDPE) and aluminum complex were determined. In the acetonitrile medium, the best fluorescence intensity of the DHDPE-Al complex was observed at lambda ex = 280 nm, lambda em = 391 nm (excitation and emission wavelengths). For optimum complex formation, the ideal pH, duration, and temperature were 4.5, 20 min, and 25 degrees C, respectively. Within the ranges of 0.027-0.27 and 0.27-2.70 ppm aluminum concentrations, [Al3+]-F.I. Calibration graphs were linear. The fluorimetric aluminum measurement method was applied to diverse water sources using the newly synthesized macro molecular Schiff base DHDPE as the ligand. The aluminum concentration in water inflow to KOSKI (Konya Water and Sewerage Administration) was doubled as a result of the examination when compared to other samples of water.Item A Game-Changing Equation During The Etching Of Tuning Forks And Its Verification Through Experiments(Başkent Üniversitesi Mühendislik Fakültesi, 2024-08-05) Erbas, Kadir Can; Erdogan, Mebrure; Serdaroglu, Dilek cokeliler; Kocum, Ismail CengizQuartz tuning fork (QTF) sensors, characterized by simplicity, low cost, and high-quality factor, represent a significant subset. This study delves into the etching dynamics of QTF systems, crucial for sensor applications like quartz crystal microbalance (QCM). Both theoretical and experimental investigations into QTF etching, via methods like electro-etching for large-scale tuning forks (TF) and low-pressure radio frequency (RF) plasma treatment for QTFs, have been conducted. Surprisingly, post-etching measurements reveal a lower vibrational frequency for both large-scale TFs and QTFs compared to their bare counterparts, unlike QCM sensors. A novel formula correlating this frequency reduction to mass loss has been proposed and validated through lots of experiments. Notably, longitudinal homogeneity emerges as a pivotal factor influencing the accuracy of the proposed formula. In summary, the novel mathematical framework presented herein is poised to catalyze the widespread adoption of low-cost QTFs as mass-sensitive biosensors, marking a significant advancement in the field.Item Why People Make Friends: Evidence From 12 Nations(Başkent Üniversitesi Fen Edebiyat Fakültesi, 2024-07-10) Apostolou, Menelaos; Sullman, Mark J. M.; Ayers, Jessica D.; Blachnio, Agata; Choubisa, Rajneesh; Gadelrab, Hesham F; Hill, Tetiana; Kamble, Shanmukh; Lisun, Yanina; Manrique-Millones, Denisse; Millones-Rivalles, Rosa; Ohtsubo, Yohsuke; Przepiorka, Aneta; Tekes, Burcu; Cruz, Germano Vera; Wang, Yan; Watanabe, Yukino; Ghorbani, AryaPeople make friends for a variety of reasons. The current study aimed to explore these reasons and the role of the Dark Triad in predicting them, using self-report questionnaires in a sample drawn from 12 countries. We found that the most important reasons for making friends were having people around with desirable traits such as compatibility, who could provide support and be relied upon in times of need, and with whom one could frequently socialize. Less important reasons included achieving self-serving goals such as career advancement and securing an intimate partner. We found small effects of age, sex, and relationship status. Furthermore, higher scores in Machiavellianism and Narcissism were associated with a greater emphasis on all reasons, particularly on achieving self-serving goals. Conversely, higher Psychopathy scores were associated with a lower importance placed on all reasons except mating, where they were associated with higher importance.Item Accelerated Evaluation of Blocking Flowshop Scheduling With Total Flow Time Criteria Using A Generalized Critical Machine-Based Approach(Başkent Üniversitesi Mühendislik Fakültesi, 2024-07-10) Han, Yuyan; Wang, Yuting; Pan, Quan-ke; Wang, Ling; Tasgetiren, FatihDespite the considerable advances in the research of the blocking flowshop scheduling problem (BFSP), several unresolved challenges persist. Algorithmic complexity presents hurdles. Although the insertion-based method is considered to generate superior solutions, its high computational demand diminishes the efficiency of algorithms, especially within large-scale sequences. The existing accelerated evaluation methods cannot utilize the existing information to quickly calculate the total flow time or the total tardiness time of the changed sequence after the job insertion, but recalculates it from scratch. This does not significantly reduce computational effort and needs to be further improved. In this paper, we delve into the intrinsic features of these challenges, proposing a generalized accelerated critical machine-based evaluation tailored for the total flow time and tardiness criteria of the BFSP with and without sequence-dependent setup times. First, we propose three theorems, one corollary, and their proofs based on the critical machine. Second, we propose the accelerated evaluation procedure based on these theorems to calculate the objectives related to the total flow time. Third, we also extend the proposed accelerated evaluation method to the BFSP with sequence-dependent setup times, aiming to significantly reduce the time complexity. Finally, we conduct four experiments on five well-known benchmarks (a total of 3540 test instances). Through statistical analysis, it becomes evident that our computational efforts have significantly decreased in computing both the total flow time and the total tardiness time. This performance enhancement is superior to the effectiveness of existing acceleration techniques.Item Automated Detection of type 1 ROP, type 2 ROP and A-ROP Based on Deep Learning(Başkent Üniversitesi Mühendislik Fakültesi, 2024-07-02) Yenice, Esay Kiran; Kara, Caner; Erdas, Cagatay BerkePurposeTo provide automatic detection of Type 1 retinopathy of prematurity (ROP), Type 2 ROP, and A-ROP by deep learning-based analysis of fundus images obtained by clinical examination using convolutional neural networks.Material and methodsA total of 634 fundus images of 317 premature infants born at 23-34 weeks of gestation were evaluated. After image pre-processing, we obtained a rectangular region (ROI). RegNetY002 was used for algorithm training, and stratified 10-fold cross-validation was applied during training to evaluate and standardize our model. The model's performance was reported as accuracy and specificity and described by the receiver operating characteristic (ROC) curve and area under the curve (AUC).ResultsThe model achieved 0.98 accuracy and 0.98 specificity in detecting Type 2 ROP versus Type 1 ROP and A-ROP. On the other hand, as a result of the analysis of ROI regions, the model achieved 0.90 accuracy and 0.95 specificity in detecting Stage 2 ROP versus Stage 3 ROP and 0.91 accuracy and 0.92 specificity in detecting A-ROP versus Type 1 ROP. The AUC scores were 0.98 for Type 2 ROP versus Type 1 ROP and A-ROP, 0.85 for Stage 2 ROP versus Stage 3 ROP, and 0.91 for A-ROP versus Type 1 ROP.ConclusionOur study demonstrated that ROP classification by DL-based analysis of fundus images can be distinguished with high accuracy and specificity. Integrating DL-based artificial intelligence algorithms into clinical practice may reduce the workload of ophthalmologists in the future and provide support in decision-making in the management of ROP.Item Approximation Theorems Via Pp-statistical Convergence on Weighted Spaces(Başkent Üniversitesi Mühendislik Fakültesi, 2024-07-08) Yildiz, Sevda; Bayram, Nilay SahinIn this paper, we obtain some Korovkin type approximation theorems for double sequences of positive linear operators on two-dimensional weighted spaces via statistical type convergence method with respect to power series method. Additionally, we calculate the rate of convergence. As an application, we provide an approximation using the generalization of Gadjiev-Ibragimov operators for P-p-statistical convergence. Our results are meaningful and stronger than those previously given for two-dimensional weighted spaces.Item Asymptotic Derivation of Consistent thin Shell Equations for a Fluid-Loaded Elastic Annulus(Başkent Üniversitesi Mühendislik Fakültesi, 2024-07-08) Yucel, H.; Kaplunov, J.; Ege, N.; Erbas, B.The classical time-harmonic plane strain problem for a fluid-loaded cylindrical elastic shell is revisited. The results of the low-frequency asymptotic analysis, including explicit formulae for eigenfrequencies, are presented. A refined version of the semi-membrane shell theory is formulated. It is shown that the shell inertia does not affect significantly the lowest eigenfrequencies. It is also demonstrated that the ring stress component has a parabolic linear variation.