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A novel method to enhance medical image reconstruction using Genetic Algorithm and Incremental Principal Component Analysis
No full textMedical imaging has an crucial role in modern healthcare and helps diagnosing and treating for a variety of medical conditions. However, the quality of medical images can be affected by factors such as noise, artifacts, and limited resolution. This paper proposes a novel approach for enhancing the reconstruction of medical images by combining Genetic Algorithm (GA) with Incremental Principal Component Analysis (IPCA). The proposed method aims to improve image quality by extracting relevant features from the original image using GA, followed by reconstruction using IPCA. Through this comprehensive approach, the goal is to enhance the reconstruction of medical images and improve their diagnostic utility in clinical practice. To prove the validity of the proposed method, five different magnetic resonance (MR) images of the shoulder joints are used and the image quality are measured using the signal-to-noise ratio (SNR) terminology with peak signal-to-noise ratio (PSNR), a structural similarity index measure (SSIM) and contrast-to-noise ratio (CNR). The results demonstrate significant improvements in image quality, confirming the effectiveness of the proposed method in enhancing the reconstruction of medical images
The examination of the relationship between the entrepreneurship levels and unemployment anxiety of conservatory students in terms of some socio-demographic variables
No full textThis study investigates the relationship between entrepreneurial levels and unemployment anxiety among conservatory students, focusing on the impact of socio-demographic variables. Using a quantitative approach with a correlational survey design, the study sampled 168 conservatory students via simple random sampling. Data collection tools included the Entrepreneurial Scale for University Students (Yılmaz & Sünbül, 2009), the Unemployment Anxiety Scale (Özder et al., 2018), and a researcher-developed Personal Data Form. Parametric tests were applied for statistical analysis due to the normal distribution of the data. The results showed no significant effects of gender, age, grade level, or department on entrepreneurial levels or unemployment anxiety. Notably, participants from the middle-income group demonstrated significantly higher entrepreneurial levels compared to those from the high-income group. Additionally, the high-income group experienced lower unemployment anxiety related to reduced labor demand than the low-income group, while the latter reported higher constant anxiety due to unemployment. Environmental factors were found to have a stronger impact on both low- and high-income groups than on their middle-income peers. Increased concerns about labor demand were associated with a corresponding rise in students’ entrepreneurial levels. In contrast, greater exposure to negative environmental factors related to unemployment was associated with lower entrepreneurial levels.</jats:p
The effect of two different video demonstrations on pain and anxiety in children undergoing adenotonsillectomy: A randomized controlled trial
No full textThe study was conducted to determine the effect of two different video demonstrations on pain and anxiety in children undergoing adenotonsillectomy.This randomized controlled trial (NCT06339866) was conducted by randomly assigning children aged 6-12 years who underwent adenotonsillectomy to three groups (animation group = 34, cartoon group = 32 and control group = 32). Data were collected using Sociodemographic Questionnaire, Wong-Baker Faces Pain Rating Scale, Child Anxiety Scale-Conditioning (CAS-C).The pain score of the children in the control group was found to be significantly higher than that of the other groups (p < 0.05). Furthermore, the pain score of the children in the cartoon group was found to be significantly higher than that of the children in the educational animation group (p < 0.05). In all of the parent and nurse assessments, the mean scores of the children in the education group were found to be lower after surgery compared to the preoperative period (p < 0.001). A negative correlation was observed between Wong-Baker Faces Expressions Pain Rating Scale scores and change in CAS-C scores (p < 0.05). The changes in CAS-C scores accounted for 26.1 % of the total variance in pain scores according to the children's assessment, 19.0 % according to the parents' assessment, and 42.6 % according to the nurses' assessment. The intraclass correlation analysis was conducted to assess the agreement between the mean scores of children, parents, and nurses on the Wong-Baker Faces Expressions Pain Rating Scale and the CAS-C. The results demonstrated excellent agreement (p < 0.001).The use of educational animation and cartoons in the preoperative period has a significant effect on reducing postoperative anxiety and pain levels in children. The use of educational animation was found to be the most effective method. In future studies, it is recommended that more impressive videos and presentations with technological developments be used comparatively both in children undergoing adenotonsillectomy and in children undergoing different surgical procedures
On the Gas Adsorption & Desorption Characteristics for Some Turkish Lignites in Terms of Coal Quality Parameters
No full textGas sorption capacity in coals is a well-researched topic, yet the complexity of experimental setups often limits detailed reporting. Understanding coal gas adsorption and seam gas content is essential for predicting and preventing mine gas outbursts and explosions. Therefore, characterizing coal samples based on their adsorption capacities is crucial. This study explores the adsorption of nitrogen, carbon dioxide, and methane across different coals and plots isotherms to assess the impact of gas type, pressure, and coal quality parameters. Results indicate that methane can adsorb even at low pressures in the Dursunbey sample, while higher pressures are required for carbon dioxide and nitrogen. The study also finds a strong correlation between Langmuir volume and ash percentage on an original basis, with nitrogen showing the highest correlation (R² = 0.7), followed by methane (R² = 0.69). Carbon dioxide, however, exhibits a weaker correlation (R² = 0.44).</jats:p
Mucosal Wetness, Hyposalivation, and Local Defense in Periodontal Inflammation
No full textABSTRACTObjectiveTo evaluate the potential relationship between local salivary coating of mucosal surfaces, clinical periodontal status, hyposalivation, and local inflammatory response with a specific reference for MUC4 and TNF‐α levels.Materials and MethodsBased on their salivary flow rates, 24 hyposalivators and 26 normosalivators were recruited. Mucosal wetness (MW) and mucosal surface pH values were determined. Clinical periodontal parameters were recorded and gingival crevicular fluid (GCF) samples were obtained. Mucin 4 (MUC4) and TNF‐α levels in local and whole salivary and GCF samples were determined with ELISA kits.ResultsGI and BoP were significantly higher in the hyposalivation group, while MW and mucosal pH values were significantly lower in hyposalivators, except for the labial surface. MUC4 and TNF‐α levels showed significant differences among the groups. In the anterior region, GCF TNF‐α concentration was high in hyposalivation patients; in the molar region, GCF MUC4 was significantly higher in normosalivators.ConclusionsBased on the differences which MW presented at local sites, MW may be utilized as a possible practical tool to reveal the local salivary characteristics in various clinical periodontal conditions based on the presence/extent of local inflammatory response, which may be important when the site‐specific nature of periodontal diseases is concerned.</jats:sec
Finite element modeling of mixed adhesive layer fracture mode for FRP web strengthening of steel bridges
No full text Buckling of thin-walled web plates of steel girders can be delayed using bonded glass fiber reinforced plastic (GFRP) stiffeners using the strengthening-by-stiffening (SBS) strengthening technique. The stress state between the bonded adherents (steel web and GFRP stiffener) is complex, varies greatly pre- and post-buckling, and causes adhesion- and/or cohesion-dominant failure modes. Full-scale experiments of SBS-strengthened steel beams showed a need to investigate the fracture mode of the adhesive layer. A finite element model of the full-scale beams was built to study the adhesive layer using sub-modeling techniques considering different steel plate thicknesses, epoxy types, and initial crack to determine the phase angle shift during web buckling. It was observed that the SBS failure is controlled by a mixed mode that starts initially with a phase angle of 29°; i.e., Mode II is the dominant failure mode during the linear phase. Thereafter, Mode I with a 59° phase angle became prevalent during the nonlinear phase of the behavior implying that the buckling-driven failure of web plate changes the phase angle. </jats:p
Example Application of a General Chemistry Laboratory Experiment for Solving Cosmetic Product Formulation: Student Evaluation
No full textTürkiye’de Sosyal Transfer Politikalarının Gelir Dağılımına Etkisi
No full textGelir dağılımını etkilemedeki rolü nedeniyle kamu transfer politikalarının yeniden dağıtıcı etkisinin incelenmesi araştırmanın çıkış noktasıdır. Bu bağlamda Türkiye’de 2010 ile 2019 yılları arasında kamu transfer harcamalarının gelir dağılımına etkisi analiz edilmiştir. Yapılan analizde TÜİK tarafından yayınlanan Hanehalkı Bütçe Anketi mikro veri seti kullanılmıştır. Araştırmada Türkiye’de incelenen dönemde kamu transfer harcamalarının Gini katsayılarını 0,026 ile 0,030 arasında düşürerek gelir eşitsizliğini azalttığına ilişkin bulgular elde edilmiştir. Bireylerin elde ettiği emeklilik maaşları ise Gini katsayısını 0,019 ile 0,022 arasında etkilemesi sebebiyle yeniden dağıtıcı etkisi en yüksek transfer türü olduğu sonucuna ulaşılmıştır. Ayrıca emeklilik maaşı dışındaki diğer transfer türlerinin gelir eşitsizliğine etkisinin kısıtlı düzeyde olduğu gözlemlenmiştir.</jats:p
Machine Learning-Driven Flexural Performance Prediction and Experimental Investigation of Glass Fiber-Reinforced Polymer Bar-Reinforced Concrete Beams
No full textThis study experimentally examines the flexural performance, crack formation patterns, and failure mechanisms of glass fiber-reinforced polymer (GFRP) bar-reinforced concrete beams with varying concrete compressive strengths (low, moderate, and high), addressing a gap in the current literature. Furthermore, it employs an innovative machine learning approach to enhance analysis. Nine RC beams reinforced with GFRP bars, having concrete compressive strengths of low (CC20), moderate (CC30), and high (CC40), each measuring 150 × 200 × 1100 mm, were fabricated and tested under three-point bending conditions. Through the integration of three-point bending tests and machine learning-based prediction models, this study connects experimental findings with advanced analytical approaches. One of the key innovations in this study is the use of eighteen ML regression models implemented with Python’s PyCaret library, achieving an impressive average prediction accuracy of 91.5% for RC beam deflection values. In particular, the Ada Boost Regressor and Gradient Boosting Regressor models performed exceptionally well on GFRP bar-reinforced concrete beams, providing the highest number of consistent and highly accurate predictions, making them very useful tools for GFRP bar-reinforced beam ultimate load-carrying capacity/deflection predictions. The outcomes identified clear failure mechanisms: RC beams with CC20, CC30, and CC40 concrete compressive strengths typically developed a single, large flexural crack at the midpoint. Although the ultimate load-carrying capacity of GFRP bar RC beams improved with higher concrete compressive strength, CC20 and CC30 beams displayed more ductile failure behavior than CC40 beams. The ultimate load-carrying capacity of CC40 RC beams was determined to be approximately 74% higher than that of CC20 RC beams. Regardless of the concrete compressive strength class, the absence of shear cracks and the prevention of sudden failure under bending in GFRP bar-reinforced concrete beams are considered major advantages of using GFRP bar reinforcement.</jats:p