Zonguldak Bülent Ecevit University Institutional Repository
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Some Properties of Generalized Apostol-Type Frobenius–Euler–Fibonacci Polynomials
No full textIn this paper, by using the Golden Calculus, we introduce the generalized Apostol-type Frobenius–Euler–Fibonacci polynomials and numbers; additionally, we obtain various fundamental identities and properties associated with these polynomials and numbers, such as summation theorems, difference equations, derivative properties, recurrence relations, and more. Subsequently, we present summation formulas, Stirling–Fibonacci numbers of the second kind, and relationships for these polynomials and numbers. Finally, we define the new family of the generalized Apostol-type Frobenius–Euler–Fibonacci matrix and obtain some factorizations of this newly established matrix. Using Mathematica, the computational formulae and graphical representation for the mentioned polynomials are obtained.</jats:p
Blood Culture Negative Endocarditis; What Do Concurrent Cardiac Disorders Tell Us?
No full textAbstract Purpose: Blood culture negative endocarditis (BCNE) presents diagnostic challenges, necessitating precise identification of high-risk patient cohorts. Hence, our objective was to pinpoint high-risk cohorts for BCNE. Methods: The study included adult patients with definite endocarditis. Data was collected via the Infectious Diseases International Research Initiative (ID-IRI). The primary study analysing one of the largest case series ever reported and was published in the European Journal of Clinical Microbiology and Infectious Diseases in 2019, was conducted across 41 centres in 13 countries. We performed a re-analysis of the database to determine the predictors of BCNE. Results: 867 cases with definite endocarditis were included in the study. Blood cultures were negative in 101 (11.65%) patients. We disclosed that as patients age, the likelihood of a negative blood culture significantly decreases (OR 0.975, 95% CI 0.963-0.987, p<0.001). Additionally, factors such as rheumatic heart disease (OR 2.036, 95% CI 0.970-4.276, p=0.049), aortic stenosis (OR 3.066, 95% CI 1.564-6.010, p=0.001), mitral regurgitation (OR 1.693, 95% CI 1.012-2.833, p=0.045), and prosthetic valves (OR 2.539, 95% CI 1.599-4.031, p<0.001) are associated with higher likelihoods of negative blood cultures. Our model can predict whether a patient falls into the culture-negative or culture-positive groups with a threshold of 0.104 (AUC±SE=0.707±0.027). The final model demonstrates a sensitivity of 70.3% and a specificity of 57.0%. Conclusion: Our study reveals a high prevalence of negative blood cultures in patients with concurrent cardiac disorders, particularly in younger cases. Therefore, caution is indicated in diagnosing and treating endocarditis in these particular patient subgroups.</jats:p
YATIRIM TEŞVİKLERİ VE DIŞ TİCARET İLİŞKİSİ: ZONGULDAK İLİ ÖRNEĞİ
No full textÜlkemizde uygulanan yatırım teşvik sistemi bölgesel gelişmişlik farklılıklarını azaltmayı amaçlamaktadır. Farklı parametreler baz alınarak hesaplanan İllerin Sosyo-Ekonomik Gelişmişlik Sırlaması yatırım teşvik sisteminin ana girdisini oluşturmaktadır. SEGE çerçevesinde belirlenen sıralamaya bağlı olarak ülke genelinde 6 gelişmişlik bölgesi ortaya çıkmaktadır. Gelişmişlik farklılıkları yatırımlar için uygulanacak vergisel avantajların oran ve kapsamında değişiklik ortaya koymaktadır. Bu farklılıklar o bölgenin ya da ilin yatırım çekme potansiyelini yakından etkilemektedir. Zonguldak ili uzun bir süredir açıklanan SEGE kriterlerine göre 3. gelişmişlik bölgesi içerisine girmektedir. Buna bağlı olarak il genelinde bir takım vergisel avantajlar elde edilmektedir. Bu avantajları fırsat bilen yatırımcılar da Zonguldak ili sınırları içerisinde yatırımlarını hayata geçirmektedir. Gerçekleşen yatırımların başta üretim olmak üzere istihdam ve dış ticaret performansı üzerinde etkili olacağı beklenmektedir. Bu kapsamda bu çalışmada Zonguldak ilinde yatırım teşvik sisteminden kaynaklı teşvike bağlı yatırımlar ile ihracat ve ithalat arasındaki ilişki 2013-2023 dönemi için aylık veri kullanılarak nedensellik testi ile analiz edilmektedir. Elde edilen bulgulara göre teşviğe bağlı yatırımlar ile ithalat arasında karşılıklı nedensellik ilişkisi elde edilmiştir. İhracat ile teşvik arasında ise bir ilişkiye rastlanmamıştır.</jats:p
Examining the Influence of Recycled Aggregates on the Fresh and Mechanical Characteristics of High-Strength Concrete: A Comprehensive Review
No full textThis review examines the impact of recycled aggregates (RAs) on the fresh and mechanical properties of high-strength concrete (HSC). The results revealed that incorporating RAs can reduce the compressive strength of HSC by up to 25%, with strength values ranging from 40 to 70 MPa depending on the RA content. The addition of supplementary materials like silica fume, fly ash, and polycarboxylate ether significantly mitigated these negative effects, enhancing the compressive strength by approximately 15–20% compared with the control mixes without additives. Furthermore, the tensile strength was observed to decrease by up to 18% with increasing RA content, but fiber reinforcement improved this by 10%, demonstrating the potential of additives to offset mechanical weaknesses. The modulus of elasticity also declined by up to 30% with higher RA dosages, highlighting the critical impact of the adhered mortar quality on the overall stiffness of the concrete. According to the literature, it was noticed that, when the dosage of RCAs is increased, there is a drop in the strength activity index (SAI). When the substitute dosage exceeded 50%, the SAI decreased. These findings underscore the importance of using optimized additive combinations to improve the mechanical performance of RA concrete, making it a viable option for sustainable construction. Overall, the findings suggest that, although RAs may negatively affect certain physical traits of HSC, the use of appropriate additives can optimize its performance, making it a viable option for sustainable construction practices.</jats:p
Dynamics of the Relationship between Inflation and Interest Rates: Testing For the Fisher Hypothesis with Structural Break(S) and Parameter Stability
No full textIn the present study, the Fisher hypothesis that considers a one-to-one and unidirectional relationship between inflation and interest rates was tested using a quarterly frequency dataset for E-7 countries. Due to the fact that parameter constancy was not established in the study, Arai & Kurozumu and Kejriwal test techniques were used and it was found that Fisher effect was valid in weak and strong forms for country groups excluding Russia. At the same time, due to the fact that coefficient indicator modulus observed in slope parameters after structural changes had negative values, contractionary monetary policies in these economies where inflation targeting strategies were implemented resulted in weakening of the relationship between inflation and interest rate variables.</jats:p
N-doped carbon nanospheres synthesized from a newly designed eco-friendly sustainable polymer for highly selective CO2 capture
No full textN-doped carbon nanospheres and porous carbon were produced by a hydrothermal template and the activation of hexamethylenetetramine (HMTA as a nitrogen source and activator) and ZnCl2 (only as an activator) from a poly(Ri-S-ε-CL-PDMS) multiblock/graft copolymer produced using a renewable resource and eco-friendly autoxidation. N-doped carbon nanospheres (PPiSiHMTA) exhibited excellent CO2 adsorption (2.73 mmol/g at 0 °C and 0.15 atm, 1.72 mmol/g at 25 °C and 0.15 atm) and CO2/N2 selectivity (344-512). Despite the higher BET surface area and pore volume, porous carbon (PPiSi) showed low CO2 adsorption (1.21 and 0.71 mmol/g, 0.15 atm) and CO2/N2 selectivity (57 and 112). PPiSiHMTA and PPiSi have low isosteric heats of adsorption (Qst, 18-33 kJ/mol) and stability in humid environments. In addition, PPiSiHMTA exhibited an excellent CO2 recycling performance. The experimental data on CO₂ adsorption was evaluated using various isotherm models, including Freundlich, Langmuir, Sips, and Temkin. The results demonstrated a nearly perfect fit between the Freundlich isotherm and the experimental data, indicating the heterogeneous nature of the adsorbent surfaces. Our study is promising for industrial applications, offering excellent CO2 adsorption, CO2/N2 selectivity, moisture stability, and porous material fabrication strategies
Alevi-Sünni Evliliklerin Çocukların Din Eğitimine Ve Aile İlişkilerine Etkileri
No full textBu çalışmada dinî anlayış farklılığına dayalı evliliklerde ebeveynlerin din olgusu ve çocukların din eğitimine dair görüşleri incelenmektir. Son yıllarda dinî anlayış farklılığına dayalı karma evliliklerde dinin yeri ve önemi üzerine yapılan çalışmalar artsa da çocukların din eğitimine yönelik tutumlarıyla ilgili araştırmaların yeterli düzeyde olduğu söylenememektedir. Dolayısıyla bu araştırma ile var olan literatüre katkı sağlamak ve alandan bir kesit sunmak amaçlanmıştır. Nitel araştırma teknikleri kullanılan çalışmaya Sivas, Ankara ve Tunceli’de yaşayan kartopu ve amaçlı örnek yoluyla ulaşılan on aile katılmıştır. Araştırmada kullanılan veriler anket ve yarı-yapılandırılmış görüşme formları ile toplanmıştır. Veriler içerik analizi ile değerlendirilmiştir. Dinî anlayış farklılıklarının din olgusuna ve çocukların din eğitimine çok belirgin bir etkisinin olmadığı saptanmıştır. Ebeveynlerin neredeyse tamamı çocukların her iki dinî anlayışa dair deneyim ve bilgi edinerek kendi yollarını tercih etmelerini arzu ettiklerini dile getirmişlerdir. Alevi-Sünni geleneği barındıran ailelerde temelde iki konunun problemlere yol açabileceği görülmüştür. Bu konulardan ilki katılımcıların evlilik arzusuna çeşitli sebeplerle ailenin ve yakın çevrenin karşı çıkmasıdır. İkincisi ise çocukların din eğitimidir. Ailede din eğitim verilmesi ve çocukların dinî kimliği ayrı bir çalışma olarak ele alınmıştır. Dolayısıyla bu çalışmada toplumda da tartışılagelen “zorunlu” din eğitimi faaliyetleri ile ilgili katılımcıların düşünceleri değerlendirilmiştir. Katılımcıların görüşleri literatürdeki bulgulara paralel olarak “derslerin kaldırılması, seçmeli hâle getirilmesi, zorunlu statüsün korunmasıyla birlikte derslerin iyileştirilmesi” şeklinde üç kategoride toplanmıştır. Yapılan görüşmeler sonucunda katılımcıların çoğunlukla dışsal faktörlerden dolayı tartışmalar yaşanabildiği, kendi dinî anlayışlarının aile hayatında, dinî tutum ve çocuk yetiştirmede herhangi bir etkisinin olmadığı görülmüştür. Söz konusu iki alandaki gerilimin azalması için önyargılardan sıyrılmak, diğerini olduğu gibi kabul, dürüstlük, güven ve iletişime açık diyalog ortamının gerekliliğine parmak basılmıştır.</p
Work stress and obsessive-compulsive symptoms in nurses and office workers: a comparative study
No full textObjectives. This study aims to compare the work stress and obsessive-compulsive symptoms of nurses and office workers and to determine the relationship between work stress and obsessive-compulsive symptoms.Methods. A total of 127 nurses and 127 office workers participated in the cross-sectional study and comparative study. Data were collected using the perceived work stress scale and the Maudsley obsessive-compulsive inventory.Results. Nurses had higher work stress scores (p = 0.003) in general than office workers. In particular, nurses with a low (p 0.05) between obsessive-compulsive symptom scores. There was a positive significant relationship (p < 0.001) between work stress and obsessive-compulsive symptom scores of nurses and office workers. Work stress explains 6.1% of the obsessive-compulsive symptoms in nurses and 12.4% in office workers.Conclusion. The results of this study concluded that work stress of nurses is higher than that of office workers and work stress affects the obsessive-compulsive symptoms in both groups
CROP HEIGHT ESTIMATION OF WHEAT USING SENTINEL-1 SATELLITE IMAGERY: PRELIMINARY RESULTS
No full textAbstract. Wheat is one of the primary crop productions for half of the global production. It is the most exported cereal, which reached up to 40% according to the records of the Food and Agriculture Organization of the United Nations (FAO) in 2020. The relationship between the crop parameters and remote sensing tools has become essential for the temporal monitoring and estimations of crop growth. In this study, we investigate the relationship between crop height and Synthetic Aperture Radar (SAR) backscatter. Plant height was collected twice, in the early (13 April 2023) and late stages (21 June 2023) of wheat, for a total of 70 samples. Sentinel-1 SAR data was also attempted to be synchronized with ground measurements. For this purpose, 8 images were obtained, 4 in both ascending (8 and 15 April, 16 and 26 June) and descending (9 and 14 April, 20 and 25 June) directions. The basic steps of image pre-processing, calibration, filtering, and topography correction, were applied to each image. By evaluating the correlation coefficients between plant height and images, data with low correlations were excluded and the first three data, dated 8 April and 19 June, were used for plant height estimation. For prediction purposes, Linear Regression (LR) and Random Forest (RF) methods were evaluated with three different training data sets. The highest correlation and minimum error value were achieved by VH polarization with random forest (r = 0.868, RMSE = 5.377 cm) in the early stage and LR (r = 0.616, RMSE = 14.451 cm) in the late stage. In general, higher training (80%) and lower test data (20%) produced better results. </jats:p