Atılım Academic Archive (Atılım University)
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Fiscal Policy and Long-Run Inflation Dynamics: Evidence From a Major Emerging Market Economy
No full textThis study examines the long-run aspects of fiscal policy on inflation in T & uuml;rkiye, using a multivariate co-integration approach with quarterly data from 2006Q1 to 2024Q2. A key contribution of the study lies in its emphasis on the long-run dynamics between various budgetary policy instruments and inflation. We find no significant long-run relationship between inflation and fiscal policy measured at the aggregate level such as budget balance, total expenditures, and revenues. However, examining the specific components, we find statistically significant long-run positive relationships between inflation and indirect taxes - particularly the special consumption tax - and operational government expenditures. Recursive estimates suggest that the relationship between inflation and fiscal instruments has strengthened since 2021 when T & uuml;rkiye started to experience a high inflation episode diverging from global inflation trends with a deterioration in public finance performance. These findings align with the fiscal theory of price level, as the theory implies that persistent fiscal deficits without credible plans for future surpluses can lead to sustained inflationary pressures.Social Science Citation Inde
Modelling the Positive and Negative Interaction Between Mood and Thermal Sensation in the Built Environment Using a Combined Markov Chain Monte Carlo Algorithm and Morris Method
No full textMood states, categorized into subscales such as Tension (TEN), Anger (ANG), Fatigue (FAT), Vigour (VIG), Confusion (CON), and Depression (DEP), affect occupants' perceptions of thermal environments. This study investigates the influence of these subscales on thermal sensation, exploring both positive and negative effects. Experiments were conducted in a temperate climate zone over an extended period, including both heating and cooling seasons, with 1159 volunteers. The Morris Method was used to assess the impact of psychological parameters (TEN, ANG, FAT, VIG, CON, DEP) on thermal sensation. Markov Chain Monte Carlo (MCMC) simulations, performed via Python code developed by the authors, evaluated the positive and negative impacts of these subscales across 30,000 simulations. Results showed that VIG was the most influential parameter, while CON and FAT had negative effects (feeling cooler) on thermal sensation. These findings emphasize the complex relationship between psychological factors and thermal perception, underlining the importance of mood states in designing environments that enhance thermal comfort. The study offers valuable insights into the interplay of emotional well-being and physiological responses, contributing to environmental psychology and climate-responsive design.Scientific and Technological Research Council of Turkiye [120M890]The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This project was supported by the Scientific and Technological Research Council of Turkiye with a project number of (120M890).Science Citation Index Expande
Analytical Modeling of Nh3 Gas Sensing Using Zigzag Graphene Nanoscrolls: Energy Band Structure and Electrical Properties
No full textGraphene nanoscrolls (GNSs), a unique nanostructure of graphene, have garnered considerable attention due to their distinctive properties such as a rolled-up papyrus-like structure, adjustable core geometry, increased inner wall area, and enhanced surface-to-volume ratio. These properties make GNS a promising candidate for various nanoelectronic applications, including gas sensing devices. Despite its potential, GNS has been relatively underexplored in the context of gas sensing applications. In this study, we present a series of analytical models to characterize the behavior of zigzag graphene nanoscrolls (ZGNS)-based gas sensors in the presence of NH3 gas. The tight-binding technique, employing nearest neighbor approximation, is utilized to formulate the energy dispersion relation of GNS, incorporating the influence of gas molecule adsorption through parameters such as the hopping integral between GNS and gas and the on-site energy of adsorbed gas molecules. Furthermore, the derived energy equation is employed to establish the conductance relation and explore the impact of gas adsorption on the electrical conductance of GNS. Subsequently, the I-V characteristics of the GNS sensor are formulated, and the variations in current due to NH3 gas exposure are analyzed. The gate voltage is modeled as a function of NH3 concentration, and a sensing parameter is proposed based on current variations across different concentrations. Validation of the model is performed by comparing the obtained results with data extracted from previous studies. The findings demonstrate good agreement, underscoring the effectiveness of the proposed ZGNS-based sensor model for NH3 detection under varying environmental conditions.Atılım UniversityThe authors would like to thank Atilim University for providing research facilities and an enabling environment.Science Citation Index Expande
Predictive Factors of Cardiac Function Recovery and Mortality in Patients With Reduced Ejection Fraction Undergoing Transcatheter Aortic Valve Implantation
No full textSuygun, HakanBackground and Objectives: Patients with reduced left ventricular ejection fraction (LVEF) are reported to have unfavorable outcomes following transcatheter aortic valve implantation (TAVI). This study aims to evaluate outcomes and identify predictive factors for LVEF recovery following TAVI in patients with reduced LVEF. Materials and Methods: This retrospective study analyzed 114 patients with symptomatic severe aortic stenosis (AS) with LVEF < 40% who underwent TAVI between 2011 and 2023 at two centers. Echocardiographic parameters, including LVEF, ventricular dimensions, and relative wall thickness (RWT), were assessed at baseline and during follow-up. The outcomes and predictors of substantial LVEF improvement and mortality were analyzed using univariate and multivariate logistic regression methods. Results: Anemia (OR = 4.345, 95% CI: 1.208-15.626, p = 0.024), RWT (OR = 1.224, 95% CI: 1.064-1.407, p = 0.005), and early post-procedural changes in left ventricular end-systolic dimension (LVESD) (OR = 1.297, 95% CI: 1.037-1.622, p = 0.023) and left ventricular end-diastolic dimension (LVEDD) (OR = 1.346, 95% CI: 1.034-1.753, p = 0.027) at one-month follow-up were identified as significant factors associated with LVEF recovery at one year. Regarding factors related to mortality, higher baseline AVMG levels were associated with a lower probability of death after one year (OR = 0.926, 95% CI: 0.875-0.979, p = 0.007). Conversely, a more limited increase in LVEF from baseline to the final follow-up was linked to poor prognosis and higher mortality at one year (95% CI: 1.045-1.594, p = 0.018). Conclusions: This study demonstrated that TAVI in patients with AS and reduced LVEF can be performed with high procedural success, low mortality, and significant improvement in cardiac function during follow-up. Additionally, anemia, baseline RWT, and early post-procedural changes in LVESD and LVEDD were identified as factors associated with LVEF recovery. Baseline AVMG and changes in LVEF at the final follow-up were found to be significant predictors of total mortality.Science Citation Index Expande
Recent Studies on Use of Waste Plastics in Integrated Ironmaking
No full textAround 7% of CO2 emissions are originated from the steel production. Nearly, three-quarters of the steel produced annually are obtained from the integrated route (BF-BOF). It is known that use of coke in BF results in 1700 kg CO2 emission per ton of hot metal. In relation to zero CO2 emission target, many investigations have been conducted in steelmaking industry for many years. One of them in blast furnace process can be regarded as replacing coke with certain alternatives. In this respect, substitution of coal and coke with biomass, use of coke oven gas (COG), use of pure H-2 gas, and use of waste plastics are some examples to the efforts to reduce CO2 emissions. In this paper, the studies aiming to substitute coke with waste plastics are reviewed
Safety, Toxicity Profile and Side Effects
No full textSince Janus kinases mediate the effects of numerous inflammatory cytokines, various side effects are observed during treatment with JAK inhibitors that inhibit these kinases. Infections are the most common side effects. The development of malignancy, venous thromboembolism, major cardiovascular adverse events, nausea, acne, and various laboratory abnormalities has also been observed with the use of JAK inhibitors. With the long-term use of JAK inhibitors, their safety, toxicity and side effect profiles are better understood. © 2025 The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG
Enhancement of Lung Cancer Histopathological Image Classification Using K-Fold Cross-Validation and Vahanade-Based Digital Image Processing Pipeline
No full textKüresel kanser ölümlerinin önde gelen nedeni olan akciğer kanseri, kesin ve etkili tanı çözümleri gerektirir. Bu çalışma, LC25000 veri setinden yinelenenleri kaldırarak, üç sınıfta 14195 dengeli görüntüye (4727/4744/4724) düşüren yeni bir ön işleme adımı sunar; bu daha önce belgelenmemiş bir iyileştirmedir. 5 katlı çapraz doğrulama (5 epoch) altında InceptionResNetV2 ve ConViT-Small kullanılarak yapılan ilk sınıflandırma, hiperparametre ayarlaması olmadan benzeri görülmemiş bir maliyet etkinliği göstererek neredeyse mükemmel doğruluk (≤6 hata) elde etti. Daha düşük hesaplama gereksinimi nedeniyle seçilen ConViT-Small, TIFF dönüştürme ve renk normalizasyonu yoluyla daha da optimize edildi. Test edilen yöntemler arasında, Vahanade'nin dönüşümü Reinhard ve hibrit tekniklerden (örn. DCT-DWT, CLAHE) daha iyi performans göstererek, mükkemel doğruluk (0 hata), Kappa ve MCC puanları elde etti. Veri seti iyileştirme, hafif derin öğrenme ve sağlam görüntü işlemeyi entegre ederek, bu çalışma yüksek doğruluklu akciğer kanseri sınıflandırmasını ilerletiyor ve tıbbi görüntüleme için ölçeklenebilir çözümler sunuyor.Lung cancer, the leading cause of global cancer deaths, requires precise and efficient diagnostic solutions. This work introduces a novel preprocessing step that removes duplicates from the LC25000 dataset, reducing it to 14195 balanced images (4727/4744/4724) in three classes, which is a previously undocumented improvement. Initial classification using InceptionResNetV2 and ConViT-Small under 5-fold cross-validation (5 epochs) achieved almost perfect accuracy (≤6 errors), demonstrating unprecedented cost-effectiveness without hyperparameter tuning. ConViT-Small, selected due to its lower computational requirement, was further optimized via TIFF conversion and color normalization. Among the tested methods, Vahanade's transform outperformed Reinhard and hybrid techniques (e.g. DCT-DWT, CLAHE), achieving excellent accuracy (0 errors), Kappa, and MCC scores. By integrating dataset curation, lightweight deep learning, and robust image processing, this work advances high-accuracy lung cancer classification and provides scalable solutions for medical imaging
Evaluating Peripapillary Vessel Density and Retinal Nerve Fiber Layer Thickness in Pseudoexfoliation Syndrome: a Comparative Study
No full textPurpose: To evaluate the changes in the peripapillary vessel density and retinal nerve fiber layer thickness changes in pseudoexfoliation syndrome compared to healthy controls. Methods: The changes were studied in thirty eyes of thirty patients with pseudoexfoliation syndrome using optical coherence tomography angiography. Peripapillary vessel densities and peripapillary nerve fiber layer thicknesses were used to compare the optic nerve head characteristics in eyes with PSX and twenty-five healthy control eyes. Results: Average, superior, and inferior RNFL thicknesses were similar in both groups (p:0.055, p:0.052, p:0.116 respectively). Eyes with PSX had lower VD values compared to healthy control groups in peripapillary, superior, and inferior segments. (p:0.011, p:0.013, p:0.017 respectively). There were significant positive correlations between RNFL thickness and peripapillary vessel density in their corresponding sectors except for inferotemporal and temporal superior sectors. (p<0.05 except inferotemporal and temporal-superior sectors) Conclusion: In this study, peripapillary vessel density was found lower in eyes with pseudoexfoliation syndrome compared to age and systemic co-morbidity matched control group. These findings suggest that reduced peripapillary vessel density which may lead to ischemia might cause vulnerability to glaucomatous damage at the optic nerve head. However, further research needs to be done to establish whether the reduction of vessel density is associated with the progression to the pseudoexfoliation glaucoma and increased vulnerability to the glaucomatous damage
A Joint Analysis of the Effects of Climate Change Denial and Problem Awareness in Predicting Air Travel Behavioral Intentions
No full textDespite scientific evidence demonstrating the impact of climate change on the planet, climate change denial remains prevalent. This study aimed to determine how various forms of climate change denial and level of problem awareness predict intentions to increase or decrease the use of air travel, given its significant climatic impact. Using data collected from 301 air travelers in T & uuml;rkiye, we conducted Partial Least Squares Structural Equation Modelling (PLS-SEM) and fuzzy set Qualitative Comparative Analysis (fsQCA) to examine the symmetrical and asymmetrical effects, respectively. The data analysis revealed that denial of guilt negatively affected problem awareness and intention to decrease air travel. Literal denial had a positive effect on intention to increase air travel, while problem awareness had a negative effect. The fsQCA revealed very diverse recipes for each outcome variable, showing high coverage.Social Science Citation Inde
Right Renal Ectopia Following Major Weight Loss
No full textPresenting with severe stomach pain from sigmoid volvulus, a woman in her 90s was effectively treated with colonoscopic desufflation. Interestingly, serial imaging over 16 years demonstrated gradual cranial displacement of the right kidney to the hepato-diaphragmatic space without prior trauma, surgery or congenital abnormalities. The patient remained asymptomatic with respect to renal function despite significant anatomical displacement. No specific intervention was required for the ectopic kidney. It is important to recognise the potential for organ migration associated with ageing, significant weight loss or metabolic alterations, particularly in the context of increasing use of weight-loss medications. Awareness of such anatomical variants can prevent misinterpretation of incidental findings on clinically indicated imaging. Routine imaging solely to detect asymptomatic positional changes is not justified