767 results on '"Koyun AN"'
Search Results
2. Do deep neural networks utilize the weight space efficiently?
- Author
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Koyun, Onur Can and Töreyin, Behçet Uğur
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Computer Science - Machine Learning ,Computer Science - Artificial Intelligence - Abstract
Deep learning models like Transformers and Convolutional Neural Networks (CNNs) have revolutionized various domains, but their parameter-intensive nature hampers deployment in resource-constrained settings. In this paper, we introduce a novel concept utilizes column space and row space of weight matrices, which allows for a substantial reduction in model parameters without compromising performance. Leveraging this paradigm, we achieve parameter-efficient deep learning models.. Our approach applies to both Bottleneck and Attention layers, effectively halving the parameters while incurring only minor performance degradation. Extensive experiments conducted on the ImageNet dataset with ViT and ResNet50 demonstrate the effectiveness of our method, showcasing competitive performance when compared to traditional models. This approach not only addresses the pressing demand for parameter efficient deep learning solutions but also holds great promise for practical deployment in real-world scenarios.
- Published
- 2024
3. A candidate sex determination locus in amphibians which evolved by structural variation between X- and Y-chromosomes
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Kuhl, Heiner, Tan, Wen Hui, Klopp, Christophe, Kleiner, Wibke, Koyun, Baturalp, Ciorpac, Mitica, Feron, Romain, Knytl, Martin, Kloas, Werner, Schartl, Manfred, Winkler, Christoph, and Stöck, Matthias
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- 2024
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4. Secondary School Students' Cognitive Structures Regarding Educational Games
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Yaman, Havva, Bekar, Seyma Nur, Yildiz, Hakan, Koyun, Salih, and Nas, Sibel Er
- Abstract
To employ educational games in education as intended, it is required to show students' cognitive structures for this concept. As a result, the purpose of this research was to reveal the cognitive structures of secondary school students regarding educational games. The research was a survey-based descriptive study. A total of 340 secondary school students were included for this research, which included fifth graders (n = 80), sixth graders (n = 95), seventh graders (n = 69), and eighth graders (n = 96). Simple random sampling was used to choose the participants. Data were gathered using the Word Association Test and a drawing test. Six categories are used to organize the students' responses to the educational game's concept. "Individual gains," "lessons," "sports," "lesson tools/applications," "games," and "features of games" were all of these. Four categories were used to categorize the drawings made by the students to represent the concept of educational games: "physical ability games," "intelligent and strategy games," "puzzle," and "mixed games." As a result of this research, it is possible to conclude that students' cognitive structures for the concept of educational games include games played in classes, and educational games highlight the game aspect more. Besides that, there was little vocabulary diversity in their cognitive structures for the educational dimension. To enhance students' cognitive structures toward educational games, focus should be given to the instructional feature of educational games in research to be undertaken in the relevant field.
- Published
- 2023
5. Student Perceptions of Academic Functioning During the COVID-19 Pandemic in Germany
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Pauline A. Hendriksen, Anna H. Koyun, Johan Garssen, Ann-Kathrin Stock, and Joris C. Verster
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COVID-19 ,academic functioning ,students ,role satisfaction ,Specialties of internal medicine ,RC581-951 - Abstract
Background: The COVID-19 pandemic posed unprecedented challenges to higher education in Germany, necessitating a rapid transition to remote learning. This study evaluates the impact of the pandemic on academic functioning among German university students. Methods: An online survey was conducted with 207 students aged 18 to 35. Results: Significantly poorer academic functioning was evident during the pandemic, particularly in academic output and role satisfaction. Younger students (18 to 24 years) experienced a greater decrease in contact with teachers and lower academic output compared to older students (25 to 35 years). These findings suggest that younger students may struggle more with remote learning due to challenges in self-regulation and time management. Additionally, pandemic-induced disruptions blurred the boundaries between work and personal life, increasing stress and adversely affecting academic performance. No significant differences were found based on sex or living situation. Conclusion: Academic functioning was significantly poorer during the COVID-19 pandemic. This finding highlights the need for targeted support strategies to mitigate the negative effects of the pandemic on students’ academic performance and well-being. Further research is recommended to explore the long-term implications of the pandemic on academic outcomes and student well-being.
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- 2024
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6. Relationships between growth characteristics and GDF9 gene polymorphisms in Awassi sheep
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Selahaddin Kiraz, Seyrani Koncagul, and Hasan Koyun
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GDF9 gene/Exon2 region ,Awassi sheep ,growth traits ,SNP ,Veterinary medicine ,SF600-1100 - Abstract
The Awassi sheep, a breed with a distinctive fat tail, is bred specifically in the south-eastern region in Turkey. It has proven its adaptability to the hot environment of this region, especially in the provinces of Şanlıurfa, Hatay and Gaziantep, which are close to the Syrian border. The aim of this study was to investigate the SNP polymorphisms in the GDF9 gene/exon2 using DNA sequencing. In addition, the study investigated the relationships between SNP genotypes and growth traits, in particular birth weight (BW), weaning weight (WW) and weight at the end of the grazing season (GSW), in Awassi sheep. Four different flocks with a total of 131 Awassi lambs were used. PCR was used to amplify exon2 of the GDF9 gene region, which has a length of 815 base pairs (bp), from the genomic DNA of the Awassi sheep. Thus, four new single nucleotide polymorphisms (SNPs) were identified. The results showed that although the effects of SNP2 and SNP4 on body weight (BW) were statistically significant, only SNP4 had a significant effect on weaning weight (WW) (P
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- 2024
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7. Relationship between HALP and PNI score with 1-month mortality after CABG
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Ilhan Koyuncu and Emin Koyun
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nutrition ,coronary artery bypass grafting ,mortality ,preoperative scores ,coronary heart disease ,Nutrition. Foods and food supply ,TX341-641 - Abstract
BackgroundCoronary heart disease (CHD) is the most common cause of cardiovascular disease (CVD). CHD is among the most common causes of mortality and morbidity world wide. In addition, CHD is one of the most important causes of health expenditures world wide. Today, coronary artery bypass grafting (CABG) operations are a widely used surgical procedure and have an important place in the treatment of CHD. Many scoring systems have been evaluated to estimate the risk of mortality and morbidity. 30-day mortality rates after CABG have been reported as 1–4% in large-scale studies.ObjectivesThe aim of our study was to evaluate the relationship between 1-month mortality in patients undergoing CABG and the Hemoglobin, albumin, lymphocyte, platelet index (HALP score) and Prognostic nutritional index (PNI) calculated using laboratory data in the preoperative period.Methods and designA total of 239 patients who underwent CABG were evaluated retrospectively. Preoperative biochemical and hemogram values, demographic characteristics, comorbidities, HALP score and PNI values of the patients were recorded. The patients were divided into two groups: Exitus group (n = 51) and survival group (n = 188). The data of the two groups were compared, mainly HALP score and PNI.ResultsIt was observed that 51 of 239 patients (21.3%) developed exitus during the 30-day follow-up after CABG. When demographic data are compared; advanced age, female gender, history of DM (Diabetes Mellitus), history of HL (hyperlipidemia) and smoking were found to be associated with mortality. When laboratory data are compared; high troponin levels, low hemoglobin, low lymphocyte and low albumin levels were found to be associated with mortality. Low HALP score (p
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- 2024
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8. Marcador Prognóstico Eletrocardiográfico na Hipertensão Arterial Pulmonar: Tempo de RS
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Emin Koyun, Anil Sahin, Ahmet Yilmaz, Ferhat Dindas, Idris Bugra Cerik, and Gorkem Berna Koyun
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Eletrocardiografia ,Prognóstico ,Hipertensão Pulmonar ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Resumo Fundamento: A hipertensão pulmonar é uma condição que envolve a remodelação do ventrículo direito. A remodelação contínua também está associada ao prognóstico da doença. Durante o processo de reestruturação, alterações complexas como hipertrofia e dilatação também podem se refletir nos parâmetros eletrocardiográficos. Objetivos: Nosso estudo teve como objetivo investigar a relação entre prognóstico e parâmetros eletrocardiográficos em pacientes com hipertensão arterial pulmonar. Métodos: O estudo foi desenhado retrospectivamente e incluiu pacientes com diagnóstico de hipertensão arterial pulmonar entre 2010 e 2022. Os pacientes foram divididos em dois grupos com base no resultado de sobrevida. Vários parâmetros, incluindo parâmetros eletrocardiográficos, demográficos, ecocardiográficos, de cateter e sanguíneos, foram comparados entre os dois grupos. Um valor de p
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- 2024
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9. A New Scoring System for the Evaluation of Ibrutinib-Associated Arrhythmias in Chronic Lymphocytic Leukemia: The ACEF Score
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İlhan Koyuncu, Betül Koyuncu, Mehmet Can Uğur, Emin Koyun, Oktay Şenöz, Mustafa Doğduş, and Oktay Bilgir
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ibrutinib ,acef score ,chronic lymphocytic leukemia ,arrhythmia ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Objective: Bruton tyrosine kinase inhibition in cardiac tissue causes inhibition of the PI3K-AKT signaling pathway, which is responsible for protecting cardiac tissue during stress. Therefore, there is an increase in the risk of arrhythmia. This study explores the prediction of that risk with the Age-Creatinine-Ejection Fraction (ACEF) score as a simple scoring system based on the components of age, creatinine, and ejection fraction. Materials and Methods: Patients diagnosed with chronic lymphocytic leukemia (CLL) and receiving ibrutinib treatment for at least 1 year were evaluated with echocardiography and Holter electrocardiography and the results were compared with a control group of CLL patients who had not received treatment. ACEF score was calculated with the formula age/left ventricular ejection fraction+1 (if creatinine >2.0 mg/dL). Results: When the arrhythmia development of the patients was evaluated, no statistically significant difference was found between the control and ibrutinib groups in terms of types of arrhythmias other than paroxysmal atrial fibrillation (PAF). PAF was found to occur at rates of 8% versus 22% (p=0.042) among ibrutinib non-users versus users. For patients using ibrutinib, an ACEF score of >1.21 predicted the development of PAF with 77% sensitivity and 75% specificity (area under the curve: 0.830, 95% confidence interval: 0.698-0.962, p
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- 2024
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10. RamanFormer: A Transformer-Based Quantification Approach for Raman Mixture Components
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Onur Can Koyun, Reyhan Kevser Keser, Safa Onur Şahin, Damla Bulut, Mustafa Yorulmaz, Veysel Yücesoy, and Behçet Uğur Töreyin
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Chemistry ,QD1-999 - Published
- 2024
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11. Invited review: 'Probiotic' approaches to improving dairy production: Reassessing 'magic foo-foo dust'
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R. El Jeni, C. Villot, O.Y. Koyun, A. Osorio-Doblado, J.J. Baloyi, J.M. Lourenco, M. Steele, and T.R. Callaway
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direct-fed microbial ,eubiotic ,postbiotic ,prebiotic ,microbiome ,Dairy processing. Dairy products ,SF250.5-275 ,Dairying ,SF221-250 - Abstract
ABSTRACT: The gastrointestinal microbial consortium in dairy cattle is critical to determining the energetic status of the dairy cow from birth through her final lactation. The ruminant's microbial community can degrade a wide variety of feedstuffs, which can affect growth, as well as production rate and efficiency on the farm, but can also affect food safety, animal health, and environmental impacts of dairy production. Gut microbial diversity and density are powerful tools that can be harnessed to benefit both producers and consumers. The incentives in the United States to develop Alternatives to Antibiotics for use in food-animal production have been largely driven by the Veterinary Feed Directive and have led to an increased use of probiotic approaches to alter the gastrointestinal microbial community composition, resulting in improved heifer growth, milk production and efficiency, and animal health. However, the efficacy of direct-fed microbials or probiotics in dairy cattle has been highly variable due to specific microbial ecological factors within the host gut and its native microflora. Interactions (both synergistic and antagonistic) between the microbial ecosystem and the host animal physiology (including epithelial cells, immune system, hormones, enzyme activities, and epigenetics) are critical to understanding why some probiotics work but others do not. Increasing availability of next-generation sequencing approaches provides novel insights into how probiotic approaches change the microbial community composition in the gut that can potentially affect animal health (e.g., diarrhea or scours, gut integrity, foodborne pathogens), as well as animal performance (e.g., growth, reproduction, productivity) and fermentation parameters (e.g., pH, short-chain fatty acids, methane production, and microbial profiles) of cattle. However, it remains clear that all direct-fed microbials are not created equal and their efficacy remains highly variable and dependent on stage of production and farm environment. Collectively, data have demonstrated that probiotic effects are not limited to the simple mechanisms that have been traditionally hypothesized, but instead are part of a complex cascade of microbial ecological and host animal physiological effects that ultimately impact dairy production and profitability.
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- 2024
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12. Importance and Determination of Body Electric Current Pre and Post Feeding in Turkish Karayaka Sheep
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Rıdvan Bayram, Hasan Çelikyürek, and Hasan Koyun
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turkish karayaka sheep ,body electricity ,pre-feeding ,post-feeding ,Agriculture ,Agriculture (General) ,S1-972 - Abstract
Many scientific studies are conducted directly or indirectly with humans, animals, and plants. We believe that body electricity, which is generated and constantly present in the bodies of living beings, should be considered in scientific studies as an effective factor for production activity. We believe that body electricity should be included in the environment to bring the rumen fluids of sheep used in Daisy II rumen simulators closer to reality. In this way, the most realistic environment is created by adding the influencing factors of body electricity and many factors that can affect the outcome. The study was conducted on a total of 16 Karayaka ewes, including 4 lambs, 4 one-year-old ewes, 4 pregnant ewes and 4 lactating ewes. The data obtained in the study were collected by measuring the body electricity of the animals before and after grazing in 3 different periods for each group. At the end of the study, it was found that the value of body electricity of sheep determined at 0.12±0.001 v (volt) before feeding was higher than the value determined at 0.09±0.002 v after feeding. The difference between the two values was found to be statistically significant (P0.05) difference in the electrical body currents before and after feeding (except in lambs (P
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- 2024
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13. Focus-and-Detect: A Small Object Detection Framework for Aerial Images
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Koyun, Onur Can, Keser, Reyhan Kevser, Akkaya, İbrahim Batuhan, and Töreyin, Behçet Uğur
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Computer Science - Computer Vision and Pattern Recognition ,Computer Science - Artificial Intelligence - Abstract
Despite recent advances, object detection in aerial images is still a challenging task. Specific problems in aerial images makes the detection problem harder, such as small objects, densely packed objects, objects in different sizes and with different orientations. To address small object detection problem, we propose a two-stage object detection framework called "Focus-and-Detect". The first stage which consists of an object detector network supervised by a Gaussian Mixture Model, generates clusters of objects constituting the focused regions. The second stage, which is also an object detector network, predicts objects within the focal regions. Incomplete Box Suppression (IBS) method is also proposed to overcome the truncation effect of region search approach. Results indicate that the proposed two-stage framework achieves an AP score of 42.06 on VisDrone validation dataset, surpassing all other state-of-the-art small object detection methods reported in the literature, to the best of authors' knowledge., Comment: 12 pages, 6 figures
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- 2022
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14. Detection of Intracranial Hemorrhage from Computed Tomography Images: Diagnostic Role and Efficacy of ChatGPT-4o
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Mustafa Koyun, Zeycan Kubra Cevval, Bahadir Reis, and Bunyamin Ece
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ChatGPT ,artificial intelligence ,intracranial hemorrhage ,computed tomography ,radiology ,Medicine (General) ,R5-920 - Abstract
Background/Objectives: The role of artificial intelligence (AI) in radiological image analysis is rapidly evolving. This study evaluates the diagnostic performance of Chat Generative Pre-trained Transformer Omni (GPT-4 Omni) in detecting intracranial hemorrhages (ICHs) in non-contrast computed tomography (NCCT) images, along with its ability to classify hemorrhage type, stage, anatomical location, and associated findings. Methods: A retrospective study was conducted using 240 cases, comprising 120 ICH cases and 120 controls with normal findings. Five consecutive NCCT slices per case were selected by radiologists and analyzed by ChatGPT-4o using a standardized prompt with nine questions. Diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated by comparing the model’s results with radiologists’ assessments (the gold standard). After a two-week interval, the same dataset was re-evaluated to assess intra-observer reliability and consistency. Results: ChatGPT-4o achieved 100% accuracy in identifying imaging modality type. For ICH detection, the model demonstrated a diagnostic accuracy of 68.3%, sensitivity of 79.2%, specificity of 57.5%, PPV of 65.1%, and NPV of 73.4%. It correctly classified 34.0% of hemorrhage types and 7.3% of localizations. All ICH-positive cases were identified as acute phase (100%). In the second evaluation, diagnostic accuracy improved to 73.3%, with a sensitivity of 86.7% and a specificity of 60%. The Cohen’s Kappa coefficient for intra-observer agreement in ICH detection indicated moderate agreement (κ = 0.469). Conclusions: ChatGPT-4o shows promise in identifying imaging modalities and ICH presence but demonstrates limitations in localization and hemorrhage type classification. These findings highlight its potential for improvement through targeted training for medical applications.
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- 2025
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15. Interactions of catecholamines and GABA+ in cognitive control: Insights from EEG and 1H-MRS
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Anna Helin Koyun, Nasibeh Talebi, Annett Werner, Paul Wendiggensen, Paul Kuntke, Veit Roessner, Christian Beste, and Ann-Kathrin Stock
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Methylphenidate ,EEG ,Theta ,1H-MRS ,GABA ,Amino acid transmitter ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Catecholamines and amino acid transmitter systems are known to interact, the exact links and their impact on cognitive control functions have however remained unclear. Using a multi-modal imaging approach combining EEG and proton-magnetic resonance spectroscopy (1H-MRS), we investigated the effect of different degrees of pharmacological catecholaminergic enhancement onto theta band activity (TBA) as a measure of interference control during response inhibition and execution. It was central to our study to evaluate the predictive impact of in-vivo baseline GABA+ concentrations in the striatum, the anterior cingulate cortex (ACC) and the supplemental motor area (SMA) of healthy adults under varying degrees of methylphenidate (MPH) stimulation. We provide evidence for a predictive interrelation of baseline GABA+ concentrations in cognitive control relevant brain areas onto task-induced TBA during response control stimulated with MPH. Baseline GABA+ concentrations in the ACC, the striatum, and the SMA had a differential impact on predicting interference control-related TBA in response execution trials. GABA+ concentrations in the ACC appeared to be specifically important for TBA modulations when the cognitive effort needed for interference control was high – that is when no prior task experience exists, or in the absence of catecholaminergic enhancement with MPH. The study highlights the predictive role of baseline GABA+ concentrations in key brain areas influencing cognitive control and responsiveness to catecholaminergic enhancement, particularly in high-effort scenarios.
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- 2024
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16. Testes de Triagem Prevendo Metástase de Câncer na Etiologia do Derrame Pericárdico: HALP Score e PNI
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Emin Koyun, Ferhat Dindas, Anil Sahin, Idris Bugra Cerik, and Mustafa Dogdus
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Câncer ,Escore de hemoglobina, albumina, linfócito e plaqueta ,Índice Prognóstico Nutricional ,Efusão Pericárdica ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Resumo Fundamento: A triagem do câncer é absolutamente necessária em pacientes com derrame pericárdico, pois o câncer é uma das doenças mais graves em sua etiologia. Estudos anteriores indicaram que o índice de inflamação imunológica sistêmica (IIS), o índice prognóstico nutricional (PNI) e o escore de hemoglobina, albumina, linfócitos e plaquetas (HALP) podem ser escores relacionados ao câncer. Objetivos: Este estudo foi iniciado considerando que esses sistemas de pontuação poderiam prever o câncer na etiologia de pacientes com derrame pericárdico. Métodos: Os pacientes submetidos à pericardiocentese entre 2006 e 2022 foram analisados retrospectivamente. A pericardiocentese foi realizada em um total de 283 pacientes com derrame pericárdico ou tamponamento cardíaco de moderado a grande no período especificado. Os índices de HALP, PNI e IIS foram calculados do sangue venoso periférico retirado antes do procedimento de pericardiocentese. O nível de significância estatística foi aceito em p
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- 2024
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17. Continuous Learning and Inference of Individual Probability of SARS-CoV-2 Infection Based on Interaction Data
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Liu, Shangching, Liu, Koyun, Chiang, Hwaihai, Zhang, Jianwei, and Chang, Tsungyao
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Computer Science - Social and Information Networks ,Computer Science - Machine Learning ,Physics - Physics and Society ,68T07(Primary), 68T09(Secondary) - Abstract
This study presents a new approach to determine the likelihood of asymptomatic carriers of the SARS-CoV-2 virus by using interaction-based continuous learning and inference of individual probability (CLIIP) for contagious ranking. This approach is developed based on an individual directed graph (IDG), using multi-layer bidirectional path tracking and inference searching. The IDG is determined by the appearance timeline and spatial data that can adapt over time. Additionally, the approach takes into consideration the incubation period and several features that can represent real-world circumstances, such as the number of asymptomatic carriers present. After each update of confirmed cases, the model collects the interaction features and infers the individual person's probability of getting infected using the status of the surrounding people. The CLIIP approach is validated using the individualized bidirectional SEIR model to simulate the contagion process. Compared to traditional contact tracing methods, our approach significantly reduces the screening and quarantine required to search for the potential asymptomatic virus carriers by as much as 94%., Comment: 15 pages,6 figures,2 tables
- Published
- 2020
18. Neurophysiological mechanisms underlying the differential effect of reward prospect on response selection and inhibition
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Koyun, Anna Helin, Stock, Ann-Kathrin, and Beste, Christian
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- 2023
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19. Characterization of junegrass (Koeleria macrantha (Ledeb.) Schult.) collected from KOP region in Central Anatolia
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Koc Koyun, Nur, Acar, Ramazan, Isik, Saban, and Hakki, Erdogan E.
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- 2023
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20. Secondary School Students’ Cognitive Structures Regarding Educational Games
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Havva Yaman, Şeyma Nur Bekar, Hakan Yildiz, Salih Koyun, and Sibel Er Nas
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cognitive structures ,educational games ,secondary school students ,Theory and practice of education ,LB5-3640 ,Science - Abstract
To employ educational games in education as intended, it is required to show students’ cognitive structures for this concept. As a result, the purpose of this research was to reveal the cognitive structures of secondary school students regarding educational games. The research was a survey-based descriptive study. A total of 340 secondary school students were included for this research, which included fifth graders (n=80), sixth graders (n=95), seventh graders (n=69), and eighth graders (n=96). Simple random sampling was used to choose the participants. Data were gathered using the Word Association Test (WAT) and a drawing test. Six categories are used to organize the students' responses to the educational game's concept. ‘Individual gains,’ ‘lessons,’ ‘sports,’ ‘lesson tools/applications,’ ‘games,’ and ‘features of games’ were all of these. Four categories were used to categorize the drawings made by the students to represent the concept of educational games: ‘physical ability games,’ ‘intelligent and strategy games,’ ‘puzzle,’ and ‘mixed games.’ As a result of this research, it is possible to conclude that students’ cognitive structures for the concept of educational games include games played in classes, and educational games highlight the game aspect more. Besides that, there was little vocabulary diversity in their cognitive structures for the educational dimension. To enhance students' cognitive structures toward educational games, focus should be given to the instructional feature of educational games in research to be undertaken in the relevant field.
- Published
- 2023
- Full Text
- View/download PDF
21. Eltrombopag for the Treatment of Poor Graft Function Following Haematopoietic Cell Transplantation: Real-Life Data
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Ekin Kırcalı, Güldane Cengiz Seval, Cemaleddin Öztürk, Hülya Yılmaz, Derya Koyun, Sinem Civriz Bozdağ, Selami Koçak Toprak, Pervin Topçuoğlu, Önder Arslan, Muhit Özcan, Taner Demirer, Osman İlhan, Günhan Gürman, Meral Beksaç, and Meltem Kurt Yüksel
- Subjects
Medicine - Abstract
Background: Eltrombopag has an off-label indication for haematopoietic cell transplantation in patients experiencing delayed thrombocyte recovery and/or thrombocytopaenia. Aims: To present our centre’s experience of using this agent not only for post- haematopoietic cell transplantation thrombocytopaenia but also for poor graft functioning in the post-haematopoietic cell transplantation setting. Study Design: Retrospective cross-sectional study. Methods: Thirty-nine patients who had persistent cytopaenia following haematopoietic cell transplantation and treated with eltrombopag at our centre between October 2011 and December 2021 were retrospectively identified. During this period, 9 (23.1%) and 30 (76.9%) patients who underwent allogeneic transplantations, respectively, received eltrombopag. Results: The female-to-male ratio was 12:27, and the median transplant age was 49 (18-70) years. Eight (20.5%) patients had isolated thrombocytopaenia, 19 (49.4%) had bi-lineage cytopaenia and 12 (30.1%) had pancytopaenia. Patients received a median of 50 mg/day (25-150 mg/day) of eltrombopagfor a median duration of 82 (24-386) days. Nine (23.1%) patients had autologous haematopoietic cell transplantation, and 30 (76.9%) had allogeneic haematopoietic cell transplantation (14 unrelated, 9 sibling and 7 haploidentical). The median donor age was 32 (20-67) years. The median follow-up was 16.4 (1.8-84.3) months. The median pre-treatment platelet count was 11x109/l (1-23), which increased to 41x109/l (6-150). The median platelet count increment was 29.5x109/l (p = 0.001). The pre-treatment median neutrophil count was 1.19x109/l (0.39-5.1), which increased to 2.35 x109/l (0.1-5.33) (p = 0.05), and the pre-treatment median haemoglobin was 8.3 (6.2-14) g/dl, which increased to 10 (6.2-14) g/dl (p = 0.001) with eltrombopag. No eltrombopag-related hepatotoxicity occurred; however, 1 (2.6%) patient failed to continue treatment because of two consecutive episodes of deep venous thrombosis. Six (15.4%) patients were unresponsive to eltrombopag and dependent on blood product transfusions. After a median time of 82 days, 61.5% of the patients discontinued eltrombopag successfully. Conclusion: The results confirmed that eltrombopag could provide a rapid, sustained response in patients with poor graft functioning after haematopoietic cell transplantation. This finding is essential given the high rate of non-relapse mortality caused by poor graft functioning after haematopoietic cell transplantation.
- Published
- 2023
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22. What do Turkish, Spanish, and Pakistani medical students value in specialty training positions? A discrete choice experiment
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Yavuz Selim Kıyak, Işıl İrem Budakoğlu, Joaquín García-Estañ, Komal Atta, Özlem Coşkun, and Emin Koyun
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Medical students ,Discrete choice experiment ,Career choices ,Specialty training ,Special aspects of education ,LC8-6691 ,Medicine - Abstract
Abstract Background: The aim of this study was to find out specialty training preferences of senior medical students from three medical schools in Turkey, Spain, and Pakistan. Methods: A Discrete Choice Experiment was carried out using an electronic form for students in three countries in 2021–2022 term. Each choice set in the form consisted of two hypothetical specialty training positions. The attributes were location, earnings, working conditions, personal perspective, quality of education, probability of malpractice, and prestige. Conditional logit model was used to estimate participants’ preferences and “willingness to accept” values. Results: The most valued attribute was “personal perspective on specialty area” for Turkish and Spanish students, while this attribute was not meaningful for Pakistani students. Turkish students needed a 204% of change in their income for a swap between the specialty that they like and not like. This tradeoff necessitated a 300% change for Spanish students. The most valued attribute for Pakistani students, which was “working conditions”, necessitated a 97% increase in income to switch from working in good conditions to working in poor conditions. Conclusion: In this first multinational DCE study in the medical education literature, we found the preferences of medical students in Turkey, Spain, and Pakistan are affected to various extents by several factors.
- Published
- 2022
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23. PB2655: EVALUATION OF THE EFFICACY AND SAFETY IMMUNOSUPPRESSIVE THERAPY IN PATIENTS WITH ACQUIRED FACTOR VIII AND IX INHIBITOR
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Derya Koyun, Güldane Cengiz Seval, Sinem Civrizbozdağ, Muhit Özcan, and Pervin Topçuoğlu
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Published
- 2023
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24. Hirudinea (Annelida) Fauna of Some Wetlands in Bingöl Province
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Tuba Elaltunkara, Mustafa Koyun, Nimetullah Korkut, and Naim Sağlam
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hirudinea ,annelida ,fauna ,wetland ,bingöl ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Abstract
Objective:Leeches are important and reliable indicators of water quality and biodiversity in the ecosystem, so the presence of specific leech species is often closely related to basic water conditions and the presence of certain animals. This study was carried out in 2017 and 2018 in order to determine the Hirudinea fauna of some wetlands in Bingöl province. The investigation was conducted on a total of 13 stations.Methods:The water parameters of the stations were measured and recorded in situ. The collected specimens were brought alive to the Zoology Laboratory of Bingöl University Biology Department and kept alive under room temperature conditions. The diagnosis of leech samples was made through the living samples, and they were identified at the level of family, genus, and species.Results:During the study, seven species, belonging to six genera and in four families were recorded. These are; Hirudo verbana Carena, 1820, Glossiphonia complanata (L. 1758), Theromyzon tessulatum (O. F. Müller, 1774), Placopdella costata (Fr. Müller, 1846), Erpobdella octoculata (L., 1758), Erpobdella testacea (Savigny, 1820), Piscicola geometra (L., 1761).Conclusion:The locations where the study was carried out are new records for the detected leech species.
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- 2022
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25. Terahertz Harmonic Generation from Graphite Pencil Drawings
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Atiqa Arshad, Hatice Nur Koyun, Ruslan Salikhov, Michael Gensch, Igor Ilyakov, Alexey Ponomaryov, Gulloo Lal Prajapati, Thales V. A. G. de Oliveira, Kalliopi Mavridou, Jürgen Lindner, Jan-Christoph Deinert, Cumhur Gökhan Ünlü, and Sergey Kovalev
- Subjects
Dirac materials ,graphite ,nonlinear terahertz optics ,Raman spectroscopy ,terahertz harmonic generation ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
The third harmonic generation (THG) of graphite layers on paper substrate upon excitation with intense (up to 100 kV cm−1) narrowband terahertz (THz) pulses is studied. Highest THG efficiencies are comparable with those of chemical vapor deposition‐grown single‐layer graphene. Samples are hand drawn, using commercially available pencils. The THG response shows high sensitivity regarding the hatching direction relative to the THz polarization orientation. Using Raman spectroscopy, the occurrence of graphene‐like structures in the samples is confirmed. The findings demonstrate the feasibility of virtually no‐cost and easy‐to‐fabricate materials for THz nonlinear optics.
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- 2023
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26. Factors affecting nutritional quality in terms of the fatty acid composition of Cyprinion macrostomus
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N. Şen Özdemir, M. Koyun, F. Caf, and M. Kırıcı
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AI ,Cyprinion macrostomus ,EPA ,Fatty acids ,h/H ,PERMANOVA ,Nutrition. Foods and food supply ,TX341-641 - Abstract
This study aimed to evaluate the effect of different factors (season, gender, location, total lipid, weight and length) on the fatty acid composition and nutritional quality of Cyprinion macrostomus. The results were evaluated through PERMANOVA, principal coordinates (PCO), and cluster analysis for similarity ranges. An analysis of similarity (ANOSIM) was performed on the distance matrix using multiple permutations within a significant fixed effect (p < 0.05). C18:1ω9, EPA and DHA were the most important fatty acids which had an effect on the nutritional quality in all the factor groups. Total lipid amount, season and length factors were the most influential on the fatty acid compositions of C. macrostomus. Summer and Spring were the best the periods for the good nutritional quality of C. macrostomus in terms of AI (Atherogenicity index), TI (Thrombogenicity index) and h/H (Σhypocholesterolemic/Σhypercholesterolemic fatty acid index). In addition, station, gender and weight had no effect on nutritional quality. The study indicated that C. macrostomus is a potential fish meat for human nutrition with high nutritional value in terms of fatty acid composition.
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- 2023
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27. Alpha-1-Antitrypsin Experience for Steroid-Resistant Acute Graft-Versus-Host Disease
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Koyun, Derya, Seval, Güldane Cengiz, Kırcalı, Ekin, Bozdağ, Sinem Civriz, Toprak, Selami Koçak, Topçuoğlu, Pervin, Özcan, Muhit, Arslan, Önder, Demirer, Taner, İlhan, Osman, Beksaç, Meral, Gürman, Günhan, and Yüksel, Meltem Kurt
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- 2022
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28. Detection of Intracranial Hemorrhage from Computed Tomography Images: Diagnostic Role and Efficacy of ChatGPT-4o.
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Koyun, Mustafa, Cevval, Zeycan Kubra, Reis, Bahadir, and Ece, Bunyamin
- Abstract
Background/Objectives: The role of artificial intelligence (AI) in radiological image analysis is rapidly evolving. This study evaluates the diagnostic performance of Chat Generative Pre-trained Transformer Omni (GPT-4 Omni) in detecting intracranial hemorrhages (ICHs) in non-contrast computed tomography (NCCT) images, along with its ability to classify hemorrhage type, stage, anatomical location, and associated findings. Methods: A retrospective study was conducted using 240 cases, comprising 120 ICH cases and 120 controls with normal findings. Five consecutive NCCT slices per case were selected by radiologists and analyzed by ChatGPT-4o using a standardized prompt with nine questions. Diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated by comparing the model's results with radiologists' assessments (the gold standard). After a two-week interval, the same dataset was re-evaluated to assess intra-observer reliability and consistency. Results: ChatGPT-4o achieved 100% accuracy in identifying imaging modality type. For ICH detection, the model demonstrated a diagnostic accuracy of 68.3%, sensitivity of 79.2%, specificity of 57.5%, PPV of 65.1%, and NPV of 73.4%. It correctly classified 34.0% of hemorrhage types and 7.3% of localizations. All ICH-positive cases were identified as acute phase (100%). In the second evaluation, diagnostic accuracy improved to 73.3%, with a sensitivity of 86.7% and a specificity of 60%. The Cohen's Kappa coefficient for intra-observer agreement in ICH detection indicated moderate agreement (κ = 0.469). Conclusions: ChatGPT-4o shows promise in identifying imaging modalities and ICH presence but demonstrates limitations in localization and hemorrhage type classification. These findings highlight its potential for improvement through targeted training for medical applications. [ABSTRACT FROM AUTHOR]
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- 2025
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29. The Association of SYNTAX and Mehran Scores with Inflammation in Patients with Contrast- Induced Nephropathy Secondary to Acute Coronary Syndrome.
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Ömür, Sefa Erdi, Koyun, Emin, Zorlu, Çağrı, Tapar, Gülşen Genç, and Cabri, Gökhan
- Abstract
Copyright of Archives of the Turkish Society of Cardiology / Türk Kardiyoloji Derneği Arşivi is the property of KARE Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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30. Relationships between growth characteristics and GDF9 gene polymorphisms in Awassi sheep.
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Kiraz, Selahaddin, Koncagul, Seyrani, and Koyun, Hasan
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SINGLE nucleotide polymorphisms ,GENETIC polymorphisms ,BIRTH weight ,BASE pairs ,DNA sequencing - Abstract
The Awassi sheep, a breed with a distinctive fat tail, is bred specifically in the south-eastern region in Turkey. It has proven its adaptability to the hot environment of this region, especially in the provinces of Şanlıurfa, Hatay and Gaziantep, which are close to the Syrian border. The aim of this study was to investigate the SNP polymorphisms in the GDF9 gene/exon2 using DNA sequencing. In addition, the study investigated the relationships between SNP genotypes and growth traits, in particular birth weight (BW), weaning weight (WW) and weight at the end of the grazing season (GSW), in Awassi sheep. Four different flocks with a total of 131 Awassi lambs were used. PCR was used to amplify exon2 of the GDF9 gene region, which has a length of 815 base pairs (bp), from the genomic DNA of the Awassi sheep. Thus, four new single nucleotide polymorphisms (SNPs) were identified. The results showed that although the effects of SNP2 and SNP4 on body weight (BW) were statistically significant, only SNP4 had a significant effect on weaning weight (WW) (P < 0.05). In addition, SNP1 and SNP3 were found to have no significant effect on any developmental trait in the dataset. [ABSTRACT FROM AUTHOR]
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- 2024
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31. Relationship between HALP and PNI score with 1-month mortality after CABG.
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Koyuncu, Ilhan and Koyun, Emin
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- 2024
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32. Student Perceptions of Academic Functioning During the COVID-19 Pandemic in Germany.
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Hendriksen, Pauline A., Koyun, Anna H., Garssen, Johan, Stock, Ann-Kathrin, and Verster, Joris C.
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COVID-19 pandemic ,PSYCHOLOGY of students ,DISTANCE education ,STUDENT well-being ,SATISFACTION - Abstract
Background: The COVID-19 pandemic posed unprecedented challenges to higher education in Germany, necessitating a rapid transition to remote learning. This study evaluates the impact of the pandemic on academic functioning among German university students. Methods: An online survey was conducted with 207 students aged 18 to 35. Results: Significantly poorer academic functioning was evident during the pandemic, particularly in academic output and role satisfaction. Younger students (18 to 24 years) experienced a greater decrease in contact with teachers and lower academic output compared to older students (25 to 35 years). These findings suggest that younger students may struggle more with remote learning due to challenges in self-regulation and time management. Additionally, pandemic-induced disruptions blurred the boundaries between work and personal life, increasing stress and adversely affecting academic performance. No significant differences were found based on sex or living situation. Conclusion: Academic functioning was significantly poorer during the COVID-19 pandemic. This finding highlights the need for targeted support strategies to mitigate the negative effects of the pandemic on students' academic performance and well-being. Further research is recommended to explore the long-term implications of the pandemic on academic outcomes and student well-being. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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33. Mood, Quality of Life, and Immune Fitness During the COVID-19 Pandemic of Young Adults in Germany.
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Hendriksen, Pauline A., Kiani, Pantea, Koyun, Anna Helin, Garssen, Johan, Stock, Ann-Kathrin, and Verster, Joris C.
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COVID-19 pandemic ,SLEEP quality ,YOUNG adults ,QUALITY of life ,WELL-being - Abstract
Background: The COVID-19 pandemic has profoundly affected young adults' lives globally, including those in Germany. This study investigated mental health and quality of life during the pandemic, with a particular focus on mood. Immune fitness, the body's capacity to respond to health challenges (such as infections) by activating an appropriate immune response, was assessed as a physical health indicator. Methods: Data were collected from 317 participants, aged 18 to 35, via an online survey conducted between November 2021 and March 2022. Participants included 103 men (32.5%) and 214 women (67.5%), with a mean age of 25.5 years (SD = 4.1). Results: Compared to pre-pandemic levels, significant declines in mood, quality of life, immune fitness, and sleep quality were observed during the lockdown periods of the COVID-19 pandemic (p < 0.0125). The most pronounced effects were observed during the second lockdown, with declines extending into the second no-lockdown period for fatigue, depression, happiness, optimism, and immune fitness (p < 0.0125). Significant sex differences were found for the magnitude of mood effects (anxiety, depression, stress). No significant differences were found according to age or occupational status (student vs. work). Conclusions: The COVID-19 pandemic and associated lockdown periods had a significant negative effect on the mood, immune fitness, and well-being of young adults living in Germany. [ABSTRACT FROM AUTHOR]
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- 2024
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34. The Relationship Standardized Precipitation Evapotranspiration Index (SPEI) and Forage Value of Rubus Species Collected from Türkiye's Flora.
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Topçu, Gülcan Demiroğlu, Koç Koyun, Nur, and Korkmaz, Ayşegül
- Abstract
The increasing drought caused by climate change makes it difficult for rural areas reliant on pasture-based livestock farming to sustain their agricultural practices. Blackberries, a spreading species, have been selected as the material for this study due to their perennial shrub nature and their tolerance to adverse environmental conditions. Türkiye, the gene center for blackberries, is part of the Mediterranean belt and is located at the intersection of three flora regions—Mediterranean, Euro-Siberian, and Irano-Turanian. This study aims to determine the forage value of the Rubus species and other shrub/tree species (Quercus, Pistacia, and Rosa) collected and identified from these flora regions. Furthermore, a linear regression analysis established a relationship between the forage values and the SPEI, a drought index, considering the combined effects of rainfall and temperature in the collection regions. Among the Rubus species, the highest organic matter content (887.8 g kg
−1 ) was obtained from R. pruinosus. In comparison, the highest protein content (240.1 g kg−1 ) was found in cultivated blackberries in the Euro-Siberian flora region. P. lentiscus had the highest Ca content (14.4 g kg−1 ) and offered feed at the "Prime" level with 154 of RFV. The SPEI explained 87% of the variation in fructan, 89% in Mg, and 92% in ADF. Due to the perennial nature of the species studied, a strong relationship was found between their growth and forage values over a 48-month time scale using the SPEI. Consequently, the equations related to ADF, Mg, and fructan content obtained in this study can be recommended for woody species. [ABSTRACT FROM AUTHOR]- Published
- 2024
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35. RamanFormer: A Transformer-Based Quantification Approach for Raman Mixture Components
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Koyun, Onur Can, primary, Keser, Reyhan Kevser, additional, Şahin, Safa Onur, additional, Bulut, Damla, additional, Yorulmaz, Mustafa, additional, Yücesoy, Veysel, additional, and Töreyin, Behçet Uğur, additional
- Published
- 2024
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36. Effects of catecholaminergic and transcranial direct current stimulation on response inhibition
- Author
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Helin Koyun, Anna, primary, Wendiggensen, Paul, additional, Roessner, Veit, additional, Beste, Christian, additional, and Stock, Ann-Kathrin, additional
- Published
- 2024
- Full Text
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37. O Índice de Inflamação Imune Sistêmica é um Novo Marcador na Previsão da Presença e Gravidade aa Ectasia Coronariana Isolada
- Author
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Ferhat Dindas, Emin Koyun, Erdem Turkyilmaz, Ozge Ozcan Abacioglu, Arafat Yildirim, Anil Sahin, Baris Dindar, Mustafa Dogdus, and Ozkan Candan
- Subjects
Doença Arterial Coronariana/complicações ,Dilatação Patológica ,Biomarcadores ,Inflamação Imune Sistêmica ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Resumo Fundamento A patologia subjacente da ectasia da artéria coronária (EC) isolada não foi totalmente elucidada. Objetivo Nosso objetivo foi examinar a relação entre o índice de inflamação imune sistêmica (Sıı), que corresponde à multiplicação da razão neutrófilos-linfócitos (RNL) e as contagens de plaquetas, e EC isolada. Método A população do estudo retrospectivo incluiu 200 pacientes com EC isolada, 200 consecutivos com doença arterial coronariana obstrutiva e 200 consecutivos com angiografia coronária normal. Um valor de p bicaudal 517,35 tem 79% de sensibilidade, 76% de especificidade para a predição do EC [AUC: 0,832, (p
- Published
- 2023
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38. Combined treatment of sinapic acid and ellagic acid attenuates hyperglycemia in streptozotocin-induced diabetic rats
- Author
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Altındağ, Fikret, Rağbetli, Murat Çetin, Özdek, Uğur, Koyun, Necat, Ismael Alhalboosi, Jamal Khalid, and Elasan, Sadi
- Published
- 2021
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39. Laboratory and field ageing of SBS modified bitumen: Chemical properties and microstructural characterization
- Author
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Koyun, Ayse Nur, Büchner, Johannes, Wistuba, Michael P., and Grothe, Hinrich
- Published
- 2021
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40. Gamma-Aminobutyric Acid and Glutamate Concentrations in the Striatum and Anterior Cingulate Cortex Not Found to Be Associated with Cognitive Flexibility
- Author
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Ann-Kathrin Stock, Annett Werner, Paul Kuntke, Miriam-Sophie Petasch, Wiebke Bensmann, Nicolas Zink, Anna Helin Koyun, Boris B. Quednow, and Christian Beste
- Subjects
ACC ,cognitive flexibility ,GABA ,glutamate ,MRS ,striatum ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Behavioral flexibility and goal-directed behavior heavily depend on fronto-striatal networks. Within these circuits, gamma-aminobutyric acid (GABA) and glutamate play an important role in (motor) response inhibition, but it has remained largely unclear whether they are also relevant for cognitive inhibition. We hence investigated the functional role of these transmitters for cognitive inhibition during cognitive flexibility. Healthy young adults performed two paradigms assessing different aspects of cognitive flexibility. Magnetic resonance spectroscopy (MRS) was used to quantify GABA+ and total glutamate/glutamine (Glx) levels in the striatum and anterior cingulate cortex (ACC) referenced to N-acetylaspartate (NAA). We observed typical task switching and backward inhibition effects, but striatal and ACC concentrations of GABA+/NAA and Glx/NAA were not associated with cognitive flexibility in a functionally relevant manner. The assumption of null effects was underpinned by Bayesian testing. These findings suggest that behavioral and cognitive inhibition are functionally distinct faculties, that depend on (at least partly) different brain structures and neurotransmitter systems. While previous studies consistently demonstrated that motor response inhibition is modulated by ACC and striatal GABA levels, our results suggest that the functionally distinct cognitive inhibition required for successful switching is not, or at least to a much lesser degree, modulated by these factors.
- Published
- 2023
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41. Pyocyanin Isolated from Pseudomonas aeruginosa: Characterization, Biological Activity and Its Role in Cancer and Neurodegenerative Diseases
- Author
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Merve Tunca Koyun, Seda Sirin, Sinem Aslan Erdem, and Belma Aslim
- Subjects
Biological activity ,Cancer ,FT-IR spectroscopy ,GC-MS analysis ,Neurodegenerative diseases ,Pseudomonas aeruginosa ,Pyocyanin ,UV-VIS specroscopy. ,Biotechnology ,TP248.13-248.65 - Abstract
Abstract This study aimed to find a pigment of bacterial origin with protective/preventive activity against neurological injury and carcinogenesis, which may be used as a natural food additive in food activity or an active drug ingredient of an anti-neural injury/anticancer agent in the pharmaceutical industry. Within this scope, the Pseudomonas aeruginosa MB713 strain was used to produce pyocyanin. Characterization of the pyocyanin was carried out using UV-VIS, FT-IR, and GC-MS analyses. In addition, its inhibitory action on AChE and antioxidant activities were determined. The cytotoxic activities of the pyocyanin as well as its antiproliferative activities were detected. It was determined that the maximum production of the pyocyanin (51 μg/mL). The pyocyanin did not cause a cell death rate above 50% in L929 cells. The pyocyanin was found to exert an inhibitory effect on the AChE. The pyocyanin was found effective on all antioxidant parameters tested. The IC50 values of the pyocyanin on SK-MEL-30 and HT-29 cells were calculated as 72 and 179 μM, respectively. And due to the pyocyanin’s antioxidant and inhibitory effects on AChE, antiproliferative effects, and protective effects against neurodegenerative injury, the use of the pyocyanin as an active drug ingredient or a preservative food additive may be predicted. This situation can be clarified by conducting advanced molecular studies.
- Published
- 2022
- Full Text
- View/download PDF
42. High resolution nanoscale chemical analysis of bitumen surface microstructures
- Author
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Ayse N. Koyun, Julia Zakel, Sven Kayser, Hartmut Stadler, Frank N. Keutsch, and Hinrich Grothe
- Subjects
Medicine ,Science - Abstract
Abstract Surface microstructures of bitumen are key sites in atmospheric photo-oxidation leading to changes in the mechanical properties and finally resulting in cracking and rutting of the material. Investigations at the nanoscale remain challenging. Conventional combination of optical microscopy and spectroscopy cannot resolve the submicrostructures due to the Abbe restriction. For the first time, we report here respective surface domains, namely catana, peri and para phases, correlated to distinct molecules using combinations of atomic force microscopy with infrared spectroscopy and with correlative time of flight—secondary ion mass spectrometry. Chemical heterogeneities on the surface lead to selective oxidation due to their varying susceptibility to photo-oxidation. It was found, that highly oxidized compounds, are preferentially situated in the para phase, which are mainly asphaltenes, emphasising their high oxidizability. This is an impressive example how chemical visualization allows elucidation of the submicrostructures and explains their response to reactive oxygen species from the atmosphere.
- Published
- 2021
- Full Text
- View/download PDF
43. 3D printing of Osage orange extract/Chitosan scaffolds for soft tissue engineering
- Author
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Saatcioglu, Elif, Koyun, Muge, Ulag, Songul, Sahin, Ali, Yilmaz, Betul Karademir, Aksu, Burak, and Gunduz, Oguzhan
- Published
- 2021
- Full Text
- View/download PDF
44. The association between HbA1c/C-peptide levels and short-term mortality in patients diagnosed with myocardial infarction.
- Author
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Ömür, Sefa Erdi, Koyun, Emin, Cabri, Gökhan, and Zorlu, Çağri
- Published
- 2024
- Full Text
- View/download PDF
45. Interactions of Catecholamines and GABA+ in Cognitive Control: Insights from EEG and 1H-MRS
- Author
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Koyun, Anna Helin, primary, Talebi, Nasibeh, additional, Werner, Annett, additional, Wendiggensen, Paul, additional, Kuntke, Paul, additional, Roessner, Veit, additional, Beste, Christian, additional, and Stock, Ann-Kathrin, additional
- Published
- 2024
- Full Text
- View/download PDF
46. Invited review: “Probiotic” approaches to improving dairy production: Reassessing “magic foo-foo dust”
- Author
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El Jeni, R., primary, Villot, C., additional, Koyun, O.Y., additional, Osorio-Doblado, A., additional, Baloyi, J.J., additional, Lourenco, J.M., additional, Steele, M., additional, and Callaway, T.R., additional
- Published
- 2024
- Full Text
- View/download PDF
47. Importance and Determination of Body Electric Current Pre and Post Feeding in Turkish Karayaka Sheep
- Author
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Bayram, Rıdvan, primary, Çelikyürek, Hasan, additional, and Koyun, Hasan, additional
- Published
- 2024
- Full Text
- View/download PDF
48. Continuous learning and inference of individual probability of SARS-CoV-2 infection based on interaction data
- Author
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Shangching Liu, Koyun Liu, Hwaihai Chiang, Jianwei Zhang, and Tsungyao Chang
- Subjects
Medicine ,Science - Abstract
Abstract This study presents a new approach to determine the likelihood of asymptomatic carriers of the SARS-CoV-2 virus by using interaction-based continuous learning and inference of individual probability (CLIIP) for contagious ranking. This approach is developed based on an individual directed graph (IDG), using multi-layer bidirectional path tracking and inference searching. The IDG is determined by the appearance timeline and spatial data that can adapt over time. Additionally, the approach takes into consideration the incubation period and several features that can represent real-world circumstances, such as the number of asymptomatic carriers present. After each update of confirmed cases, the model collects the interaction features and infers the individual person’s probability of getting infected using the status of the surrounding people. The CLIIP approach is validated using the individualized bidirectional SEIR model to simulate the contagion process. Compared to traditional contact tracing methods, our approach significantly reduces the screening and quarantine required to search for the potential asymptomatic virus carriers by as much as 94%.
- Published
- 2021
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49. Disease Occurrence in- and the Transferal of Zoonotic Agents by North American Feedlot Cattle
- Author
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Osman Y. Koyun, Igori Balta, Nicolae Corcionivoschi, and Todd R. Callaway
- Subjects
feedlot cattle ,zoonoses ,STEC O157:H7 ,Salmonella ,Escherichia coli ,Campylobacter ,Chemical technology ,TP1-1185 - Abstract
North America is a large producer of beef and contains approximately 12% of the world’s cattle inventory. Feedlots are an integral part of modern cattle production in North America, producing a high-quality, wholesome protein food for humans. Cattle, during their final stage, are fed readily digestible high-energy density rations in feedlots. Cattle in feedlots are susceptible to certain zoonotic diseases that impact cattle health, growth performance, and carcass characteristics, as well as human health. Diseases are often transferred amongst pen-mates, but they can also originate from the environment and be spread by vectors or fomites. Pathogen carriage in the gastrointestinal tract of cattle often leads to direct or indirect contamination of foods and the feedlot environment. This leads to the recirculation of these pathogens that have fecal–oral transmission within a feedlot cattle population for an extended time. Salmonella, Shiga toxin-producing Escherichia coli, and Campylobacter are commonly associated with animal-derived foods and can be transferred to humans through several routes such as contact with infected cattle and the consumption of contaminated meat. Brucellosis, anthrax, and leptospirosis, significant but neglected zoonotic diseases with debilitating impacts on human and animal health, are also discussed.
- Published
- 2023
- Full Text
- View/download PDF
50. Static and dynamic properties of noncollinear magnetized ferromagnetic films
- Author
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Jiménez-Bustamante, J., Lindner, A. A., (0000-0003-1814-2472) Koyun Yücel, H. N., (0000-0001-8461-0743) Salikhov, R., (0000-0001-5528-5080) Lenz, K., (0000-0002-4955-515X) Lindner, J., Gallardo, R. A., Jiménez-Bustamante, J., Lindner, A. A., (0000-0003-1814-2472) Koyun Yücel, H. N., (0000-0001-8461-0743) Salikhov, R., (0000-0001-5528-5080) Lenz, K., (0000-0002-4955-515X) Lindner, J., and Gallardo, R. A.
- Abstract
The dynamic matrix method was employed to perform theoretical calculations for investigating both static and dynamic characteristics of thick ferromagnetic films. This approach considers situations where a noncollinear equilibrium magnetization exists along the thickness due to a thickness-dependent uniaxial anisotropy and inter- facial interactions in a synthetic antiferromagnet. In the former scenario, the study exposes a correlation between noncollinear static magnetization and a nonmonotonic dependence of ferromagnetic resonance frequency, where a frequency decrease is observed at low fields in the unsaturated regime. Regarding the synthetic antiferromagnet structure, the research demonstrates noncoherent magnetization rotation in the spin-flop regime, with twisted magnetization states influencing the critical and nucleation fields that define the spin-flop region. The results of the investigation were compared to the macrospin approach, where the magnetization is assumed to be uniform along the thickness. The study suggests that the contribution of noncollinear magnetic moments may mimic the role of the biquadratic interaction in the macrospin model, implying that such a biquadratic term may be over- estimated in coupled ferromagnetic films with thicknesses exceeding the material’s intrinsic exchange length. Finally, the model was compared with experimental data obtained from a Py/Ir/Py synthetic antiferromagnet, demonstrating that the theoretical consideration of a twisting equilibrium state of the magnetization precisely reproduces the observed dynamic and static properties of the nanostructure.
- Published
- 2024
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