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An Ensemble of Deep Learning Object Detection Models for Anatomical and Pathological Regions in Brain MRI
No full textThis paper proposes ensemble strategies for the deep learning object detection models carried out by combining the variants of a model and different models to enhance the anatomical and pathological object detection performance in brain MRI. In this study, with the help of the novel Gazi Brains 2020 dataset, five different anatomical parts and one pathological part that can be observed in brain MRI were identified, such as the region of interest, eye, optic nerves, lateral ventricles, third ventricle, and a whole tumor. Firstly, comprehensive benchmarking of the nine state-of-the-art object detection models was carried out to determine the capabilities of the models in detecting the anatomical and pathological parts. Then, four different ensemble strategies for nine object detectors were applied to boost the detection performance using the bounding box fusion technique. The ensemble of individual model variants increased the anatomical and pathological object detection performance by up to 10% in terms of the mean average precision (mAP). In addition, considering the class-based average precision (AP) value of the anatomical parts, an up to 18% AP improvement was achieved. Similarly, the ensemble strategy of the best different models outperformed the best individual model by 3.3% mAP. Additionally, while an up to 7% better FAUC, which is the area under the TPR vs. FPPI curve, was achieved on the Gazi Brains 2020 dataset, a 2% better FAUC score was obtained on the BraTS 2020 dataset. The proposed ensemble strategies were found to be much more efficient in finding the anatomical and pathological parts with a small number of anatomic objects, such as the optic nerve and third ventricle, and producing higher TPR values, especially at low FPPI values, compared to the best individual methods.Digital Transformation Office of the Presidency of the Republic of TuerkiyeThis study was funded by the Digital Transformation Office of the Presidency of the Republic of Tuerkiye
Teacher candidates' proficiency in utilising the REACT strategy through experimental activities
No full textIt is known that the success of a science education reform depends considerably on science teachers' knowledge, skills and activities. In accordance with this, the aim of this study is to investigate the proficiency of science teacher candidates in the use of the REACT strategy through their experimental science activities within the scope of context-based learning approach. Within this context, this study was designed in the form of a longitudinal analysis, performances were analysed periodically, and the transformation was pursued. The data obtained from documents by means of a content analysis was presented via graphical instruments through converting it into quantitative data by means of the rubric which was developed by the researchers. According to the longitudinal analysis findings, it was observed that the teacher candidates' performance in utilising the REACT strategy is parallel to the ascending number of activities.Kirikkale UniversityAssoc. Prof. Dr. Harun Celik is the coordinator of the project numbered 2020/21 financed by Kirikkale University. This project is carried out with the ethics approval of Kirikkale University Social and Human Sciences Research Ethics Committee, Decision Number: 24, dated 28.12.2020. We would like to thank Kirikkale University for their support of this project work
Cu(II) Complexes of New Sulfa Drug Schiff Base Ligands: Synthesis, Structural Characterization, Antimicrobial Activities, and Time-Killing Kinetics
No full textSynthesis of three different new sulfonamide compounds (L-1-L-3) and their Cu(II) complexes were carried out. Their structures were characterized by spectroscopic methods such as Fourier transform infrared, Proton nuclear magnetic resonance and elemental analysis. Cu(II) complexes were screened for Gram-positive, Gram-negative bacteria and against yeast using the microdilution method. In particular, CuL2 was found to have significant antimicrobial effects on Gram (-), Gram (+) and eukaryotic yeast. The results showed that CuL2 exhibited better antimicrobial activity than other complexes. Depending on the antimicrobial activity results, time killing experiments of CuL2, the most effective complex, were performed
Does the addition of choline and/or betaine to diets reduce the methionine requirements of laying quails? Assessment of performance and egg antioxidant capacity
No full textThe purpose of the present study was to assess the performance, quality of eggs internally and externally, and antioxidant capacity of yolks in laying quails with the administration of choline and betaine to diets containing reduced methionine levels. A total of 150 Japanese laying quails (Coturnix coturnix japonica) at the 10-wk age were randomly assigned to 6 experimental groups, each consisting of 5 replicates and 5 birds for 10 wk. The treatment diets were designed by adding the fol-lowing substances: 0.45% methionine (C), 0.30% methio-nine (LM), 0.30% methionine + 0.15% choline (LMC), 0.30% methionine + 0.20% betaine (LMB), 0.30% methionine + 0.075% choline + 0.10% betaine (LMCB1), 0.30% methionine + 0.15% choline + 0.20% betaine (LMCB2). The treatments did not affect perfor-mance, egg production, or egg internal quality (P > 0.05). No significant effect was determined on the damaged egg rate (P > 0.05), but the egg-breaking strength, eggshell thickness, and eggshell relative weight decreased in the LMCB2 group (P 0.05), although the lowest thiobarbi-turic acid reactive substances value was observed in the LMB compared to the control group (P < 0.05). It may be summarized that methionine can be decreased to levels of 0.30% for laying quail diets with no negative effect on performance, egg production, or egg internal quality, whereas the combination of methionine (0.30%) and beta-ine (0.2%) could improve antioxidant stability of eggs over the 10-wk experimental period. These findings pro-vide useful information to the traditional recommenda-tions on the requirements of laying quail. However, further studies are needed to test whether these effects persist throughout extended study periods
Türk Halk Müziği Solfej Kitapları Üzerine Bir İnceleme
No full textBu araştırma Türkiye’de yayımlanmış olan Türk Halk Müziği (THM) Solfej kitaplarındaki çalışmaların çeşitli yönlerden incelenmesini içermektedir. Çalışma kapsamında Türk Halk Müziği Solfej alanında yazılmış ve ulaşılabilen 8 adet kitap ve içeriğinde bulunan 902 adet solfej ve türkü incelenmiştir. Çalışmada nitel araştırma yöntemlerinden olan içerik analizi ve doküman analizi yöntemlerinden faydalanılmıştır. Araştırmanın sonucunda incelenen kitapların tamamında solfej ve örnek THM eserlerinin; vokal açıdan başlangıçta kolay tartımsal- ezgisel unsurlarla, vokal sınırları daha dar ve daha kısa alıştırmalarla başladığı ve zorlaşarak ilerleme gösterdiği, usûl ve tartımsal çeşitlilik açılarından türkülerimizin birçoğunda rastlayabileceğimiz öğeleri içerdiği, ses sahası açısından THM repertuvarında bulunan türkülere benzer içerikler taşıdığı, usûllere yönelik olarak teorik bir anlatım bulunmamakla birlikte bazı kitaplarda kısaca usûl bilgisi verildiği, kitaplardan iki tanesinde solfejler ve örnek türkülerde geçen makâm dizilerine yönelik olarak teorik bilgi bulunduğu fakat diğer kitaplarda ya hiç bilgi verilmediği ya da yalnızca makâm dizisinin gösterildiği, on beş farklı makâm dizisi ve otuz farklı usûl içerdiği, en çok bulunan makâm dizisinin Hüseynî olduğu ve en çok bulunan usûlün ise 4/4’lük usûl olduğu sonuçlarına ulaşılmıştır. Ulaşılan sonuçlar ışığında Türk Halk Müziği Solfej alanına yönelik olarak yapılacak çalışmalara dair önerilerde bulunulmuştur
A novel feature and class-based globalization technique for text classification
No full textText classification is a very important topic in the current era due to the high volume of textual data and handling. Feature selection is one of the most important steps in text classification studies, as well as significantly affecting classification performance. In the literature, filter-based global feature selection methods are widely proposed. While these methods are globalized, although they are generally performed by looking at the class information, feature information is ignored beside the class information. When calculating the score of each feature, the information of the feature should be taken into account along with the class information. To solve this problem, a new globalization technique called Feature and Class-based Weighted Sum (FCWS) which takes into account both feature and class information is proposed. FCWS method is compared with traditional globalization techniques on four datasets named as Reuters-21,578, 20Newsgroup, Enron1 and Polarity in addition to Support Vector Machines (SVM), Decision Tree (DT) and Multinomial Naive Bayes (MNB) classifiers. Also, it was employed 50, 100, 300, 500, 1000 and 3000 as dimension. Experimental studies on benchmark datasets show that the efficiency of the proposed method is higher performance than the other three methods named as maximum (MAX), sum (SUM), and weighted-sum (AVG), in most cases according to Micro-F1 and Macro-F1 scores
EFFECTS OF CORONARY ARTERY CALCIFIED PLAQUE AND STENT ON SEVERITY AND SURVIVAL OF COVID-19 PATIENTS: A DECISION TREE MODEL STUDY
No full textAim We aimed to investigate the relationship between the presence of calcified plaques and stents in coronary arteries as evaluated by the chest computed tomography severity score (CT-SS) and mortality rates in patients with COVID-19. Material and methods A single-center retrospective analysis was conducted of 492 patients (>= 18 yrs) who were hospitalized between March and June 2020. All included patients had RT-PCR tests positive for COVID-19. A radiologist recorded pulmonary imaging findings and the presence of coronary calcified plaque and/or stent, sternotomy wires, and cardiac valve replacement on initial non-contrast chest CT. Also, cardiothoracic ratios (CTR) were calculated on chest CTs. Data were analyzed using univariate and multivariate analyses and a chi-squared automatic interaction detection (CHAID) tree analysis, which was developed as a predictive model for survival of COVID-19 patients according to chest CT findings. Results The mean CT-SS value of the patients with coronary plaque was 11.88 +/- 7.88, and a significant relationship was found between CT-SS with coronary calcified plaque (p0.57. Conclusion The presence of coronary artery calcified plaque and cardiomegaly were high risks for severe prognosis and mortality in COVID-19 patients and may help to predict the survival of patients
PANDEMİ SÜRECİNDE UZAKTAN ÖĞRETİMLE YÜRÜTÜLEN ÖĞRETMENLİK UYGULAMASI DERSİNE YÖNELİK ÖĞRETMENLERİN VE ÖĞRETMEN ADAYLARININ GÖRÜŞLERİ
No full textAraştırma pandemi sürecinde uzaktan öğretimle yürütülen öğretmenlik uygulaması dersine yönelik öğretmen ve öğretmen adaylarının görüşlerini belirlemek amacıyla yapılmıştır. Araştırma nitel araştırma yöntemlerinden fenomenoloji kullanılarak yapılmıştır. Araştırmanın çalışma grubunu 2020- 2021 eğitim öğretim yılında Türkiye’nin faklı bölgelerinde ve farklı branşlarda görev yapan 32 öğretmen ve 72 öğretmen adayı oluşturmaktadır. Araştırma sonucunda hem öğretmenlerin hem de öğretmen adaylarının uygulamaya dair görüşleri alınmış ve 8’er tema ve alt temalar altında yorumlanmıştır. Bulgular değerlendirildiğinde öğretmen adaylarının uzaktan öğretim ile yürütülen öğretmenlik uygulaması dersinden beklentilerinin en çok meslek yaşamları için tecrübe edinmek olduğu ve dersin beklentilerini karşılamadığı, öğretmenler tarafından ise en çok uzaktan öğretimle dersin verimli olmadığı gibi dezavantajlarının ve kısıtlılıklarının olduğu ifade edilmiştir. Buna rağmen öğretmen adaylarının uzaktan öğretimle de olsa bu ders kapsamında öğrencilerle bir araya gelmesine imkân tanıdığı, uzaktan öğretimle nasıl ders işleneceğinin öğrenilmiş olması ve öğretmenlerin de uzaktan öğretimle öğretmen adaylarına nasıl rehberlik edileceği konusunda kendilerini geliştirmelerini sağladığı gibi avantajlarının olduğu da ulaşılan sonuçlar arasındadır
Comparative performance analysis of NACA 2414 and NACA 6409 airfoils for horizontal axis small wind turbine
No full textWhile wind energy, which has an important place among renewable energy sources, is converted into electrical energy by means of wind turbines, the designs and aerodynamic behaviors of turbine blades gain importance in order to obtain optimal efficiency. The most important factor affecting the wind energy capture performance and aerodynamic behavior of the blade is the aerofil structure. In this study, the design and comparative performance analysis of NACA 2414 and NACA 6409 series airfoils under wind turbine conditions with 1x10^6 fixed reynolds number, 0-20^0 attack angles, constant air density and ambient conditions, 3kW nominal power and 2m blade length were carried out. The designs and analyzes for both airfoils were simulated using Q-Blade software version 2.0.5.2. While designing the blade, the propeller blade was divided into 20 equal parts so that there would be no aerodynamic interaction between the elements, and analyzes were made with a calculation method based on the Blade Element Momentum (BEM) theory. As a result, by comparing different features such as lift (Cl) and drag (Cd) coefficients, pressure distribution on the blades, power coefficients, it was seen that the NACA 6409 airfoil was more efficient than the NACA 2414 airfoil for small diameter wind turbines
Global energy crises: Measures taken and policies adopted in the recent history
No full textRecent events like the COVID-19 pandemic and the Russia-Ukraine conflict have disrupted the supplydemand balance and triggered a new energy crisis, impacting the world economy. The rapid increase in the world's population, coupled with industrialization and urbanization, has exacerbated energy demand issues, affecting countries worldwide, especially the EU. As a result of these developments, countries have been prompted to take new energy measures and formulate policies to address the energy crisis. This study examines historical perspectives and conducts a comparative analysis of energy crises from the past to the present, focusing on the current energy crisis and the measures taken by various countries, including the EU member states. The study aims to explore how crises shape energy policies, how countries evaluate "opportunity windows" for new/alternative energy sources and technologies in response to crises, and how they present potential alternative energy sources for the future through the discussion of adopted energy policies. © 2024, IGI Global. All rights reserved