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Investigation of the Atomic and Thermal Performance of Al2O3 Nanoparticles/Octadecane as Phase Change Materials (PCM) in Circular Tube with Molecular Dynamics Simulation
No full textPhase change materials' heat transfer mechanism may be enhanced by high thermal conductivity nanoparticles, allowing for quicker and more efficient thermal energy storage and release. This study examined the atomic and thermal characteristics of octadecane as a phase transition material inside a circular tube using molecular dynamics modeling with Al2O3 nanoparticles. At 0.031 (+0.002) atoms/& Aring;3, the tube walls had the highest density after 20 ns. The tube's maximum recorded temperature was 751.51 (+1.01) K, and its peak velocity was 0.0078 (+0.0001) & Aring;/fs. After 20 ns, the thermal conductivity was 1.35 (+0.01) W/m & sdot;K and the heat flux was 3.84 (+0.01) W/m2. The charging and discharging times of the structure were 6.45 (+0.05) and 7.15 (+0.03) ns, respectively. This study shows how AlO3 nanoparticles can enhance the thermal performance of octadecane in energy storage applications. It also provided important information about the atomic-level behavior of these materials during phase transitions.Deanship of Research and Graduate Studies at King Khalid University [RGP2-420-46]The authors extend their appreciation to the Deanship of Research and Graduate Studies at King Khalid University for funding this work through Large Research Project under grant number RGP2-420-46.Science Citation Index Expande
Gut Microbiota in Crohn's Disease Pathogenesis
No full textInflammatory bowel diseases (IBDs) are classified into two distinct types based on the area and severity of inflammation: Crohn's disease (CD) and ulcerative colitis. In CD, gut bacteria can infiltrate mesenteric fat, causing expansion known as creeping fat, which may limit bacterial spread and inflammation but can promote fibrosis. The gut bacteria composition varies depending on whether the colon or ileum is affected. Fecal microbiota transplantation (FMT) transfers feces from a healthy donor to restore gut microbiota balance, often used in IBD patients to reduce inflammation and promote mucosal repair. The use of FMT for CD remains uncertain, with insufficient evidence to fully endorse it as a definitive treatment. While some studies suggest it may improve symptoms, questions about the duration of these improvements and the need for repeated treatments persist. There is a pressing need for methods that provide long-term benefits, as highlighted by Wu et al's research.Science Citation Index Expande
A Numerical Treatment Through Bayesian Regularization Neural Network for the Chickenpox Disease Model
No full textObjectives: The current research investigations designates the numerical solutions of the chickenpox disease model by applying a proficient optimization framework based on the artificial neural network. The mathematical form of the chickenpox disease model is divided into different categories of individuals, susceptible, vaccinated, infected, exposed, recovered, and infected with/without complications. Method: The construction of neural network is performed by using the single hidden layer and the optimization of Bayesian regularization. A dataset is assembled using the explicit Runge-Kutta technique for reducing the mean square error using the training 76 %, while 12 %, 12 % for validation and testing. The whole stochastic procedure is based on logistic sigmoid fitness function, single hidden layer structure with thirty neurons, along with the optimization capability of Bayesian regularization. Finding: The designed procedure's correctness and reliability is observed by results matching, negligible absolute error around 10−04 to 10−06, regression, error histogram, and state transmission. Moreover, the best performance values based on the mean square error are performed as 10−09 to 10−11. Novelty: The current neural network framework using the construction of a single hidden layer and the optimization of Bayesian regularization is applied first time to solve the chickenpox disease model. © 2025 Elsevier Lt
Effects of Automobile Ownership on E-Scooter Choices: the Istanbul Case
No full textE-scooters have gained momentum as a micromobility mode for several years, which created the need for research to understand the attitudes toward it. However, to the authors' knowledge, there is a research gap regarding the effects of private automobile ownership on the e-scooter choices of individuals under different traffic conditions, a factor that significantly affects the preferences. Therefore, this work aimed to investigate the effects of automobile ownership on travel mode choices where e-scooter was an option. A stated preference survey was prepared, and responses were collected from individuals in Istanbul about the mode choices, namely private transport, public transport and e-scooter. The method used to model the travel choices was Mixed Logit (ML). Two approaches were made to observe the effects of automobile ownership: Dummy variable and market segmentation. Both approaches proved that automobile ownership affected the e-scooter choices over other modes, and different models can be developed for individuals who owned automobiles and others. Results showed that there were taste variations regarding travel time among the individuals, and travel time affected the choices of automobile owners more than the others. However, no taste variations were observed regarding travel cost. Furthermore, under congested traffic conditions, the breakeven e-scooter fare was lower for automobile owners for the switch between private transport and e-scooter. In addition, cost elasticities indicated that automobile owners were more sensitive to e-scooter cost changes. Policies regarding e-scooter use can be prepared based on the findings of this research for automobile owners. Future research directions were given.The Scientific and Technological Research Council of Turkiye (TUBITAK) 1001 Research Project [123M063]; TUBITAKThis study was conducted as part of The Scientific and Technological Research Council of Turkiye (TUBITAK) 1001 Research Project, numbered 123M063, titled "Determining the Effects of Electric Scooters on Istanbul's Traffic and Environment, and Identifying the Optimal Operating Environment, Conditions, and Regulations," led by Selim Duendar with Guerkan Guenay as a researcher and Saadet Dilekci as a scholar. The authors express their gratitude to TUBITAK for their support.Social Science Citation Inde
The Crisis of Fat Body in the Neoliberal Era: the Case of Obesity in Turkey
No full textObesity research has been predominantly shaped by biomedical and political economy approaches that emphasize energy imbalance and individual responsibility. While critical perspectives challenge these narratives, they often neglect the structural and socio-economic production of obesogenic environments. This study conceptualizes obesity as a structurally embedded outcome of capitalist social relations and neoliberal restructuring, with a specific focus on the Turkish context. This study adopts a dialectical critical realist approach to analyse obesity at three levels: empirical (observable trends), actual (underlying mechanisms), and deep (structural causes). Quantitative data, obtained from authoritative institutional sources, illustrate rising obesity rates and contributing mechanisms. Qualitative data, systematically selected from academic and institutional sources, are used to examine the structural roots of obesity in capitalist social relations, focusing on how individuals function as both labour and consumers. The findings indicate that flexible labour markets contribute to obesity by increasing stress levels, while agricultural industrialisation promotes the consumption of chemical-laden, low-nutrition food. Furthermore, the commodification of health services frames obesity as an individual issue rather than a societal one, leading to ineffective treatment and prevention policies. Despite increasing scientific evidence on the biological and metabolic complexities of obesity, dominant strategies remain reductionist. Effective public health policies should move beyond profit-oriented frameworks and adopt holistic, interdisciplinary approaches that consider social, economic, and environmental factors. Further research is needed to explore transformative strategies that prioritize collective well-being over capital interests.Social Science Citation Inde
Diagnostic Accuracy of a Novel Non-Invasive Digital Technique for Assessing Gingival Phenotype: An Area Under the Curve Analysis
No full textBackground: Gingival phenotype (GP) significantly influences periodontal health and treatment outcomes. Traditional methods for assessing GP, using gingival thickness (GT) alone, may lack sufficient accuracy for reliable GP classification. The present study aims to introduce and validate a novel non-invasive digital GP assessment measuring digital GT (dGT) and digital keratinized tissue width (dKTW). The primary objective is to assess the diagnostic performance of digital gingival phenotype (dGP) in distinguishing between thick and thin phenotypes. Methods: This prospective, cross-sectional study was conducted at the Periodontology Department of Istanbul University-Cerrahpaşa, Turkey, from October to December 2024. Participants were included if they had all maxillary and mandibular anterior teeth present. Exclusion criteria included factors that could affect periodontal tissues, such as clinical attachment loss, systemic diseases (e.g., diabetes), gingival enlargement or recession, smoking, medications causing gingival hyperplasia, and melanin pigmentation. All subjects were screened for eligibility by S.K. prior to enrollment, with participants enrolled when S.K. was present at the periodontology department for preliminary examinations using a convenience sampling approach. KTW was assessed using clinical (cKTW), digital (dKTW), and rounded methods. cKTW and dKTW measured the distance between the gingival margin and mucogingival junction, while rounded KTW was calculated by rounding dKTW to the nearest whole number. GT was measured digitally in millimeters from the gingival margin level. GP was evaluated clinically (cGP) with a color-coded periodontal probe and digitally (dGP) by multiplying dKTW and dGT measurements. cKTW, dKTW, rounded KTW, dGT, and dGP are index tests, with cGP serving as the reference standard. The diagnostic accuracy of each method was evaluated using Receiver Operating Characteristic (ROC) analysis. Results: Out of 348 participants, 31 met the inclusion criteria. Since each participant’s 12 teeth were evaluated, a total of 372 teeth were included in the study. The area under the curve (AUC) values and 95% confidence intervals (CI) for each method were as follows: dGT: 0.628 (95% CI: 0.570–0.687), cKTW: 0.730 (95% CI: 0.677–0.782), dKTW: 0.714 (95% CI: 0.661–0.767), rounded KTW: 0.710 (95% CI: 0.657–0.763), and dGP: 0.734 (95% CI: 0.683–0.785). The dGP model exhibited the highest diagnostic accuracy, while the dGT model showed the lowest. Conclusions: The findings suggest that the digital gingival phenotype assessment provides superior diagnostic accuracy compared to other methods, achieving the highest AUC value. This demonstrates its efficacy in classifying GP and offers a reliable and accurate alternative to traditional clinical techniques for GP classification. Registration: No trial registration was performed, as no invasive procedures were conducted in this study. © The Author(s) 2025.Science Citation Index Expande
Evaluation of Pi3k Levels and Mirna124-5p Expression Levels in Serum Samples From Patients With Lung Cancer
No full textBackground/Aim: Lung cancers are malignant neoplasms located in the lung tissues. miRNAs are short non-coding RNAs. It is known that miRNA-124 prevents metastasis in lung cancers. The phosphatidylinositol 3-kinases (PI3K) signaling pathway, a basic signaling pathway interconnected with other pathways, is activated during cancer development. This study aimed to compare miRNA-124-5p and PI3K serum levels in patient and control groups. Materials and Methods: miRNA isolated from patient and control serum samples were converted into cDNA. miRNA- 124-5p expression was determined using Real-Time PCR and a SYBR GREEN kit. PI3K serum level was determined using the Enzyme-Linked Immunosorbent Assay. Results: While miRNA-124-5p serum level was statistically significantly lower in the patient group (p>0.02), serum PI3K level was higher in the patient group than in the control group but the difference was not statistically significant (p>0.11). Conclusion: Lower serum levels of miRNA-124-5p and high PI3K levels observed in the patient group, compared to the control group, may be associated with a poor disease prognosis. © 2025 The Author(s). Anticancer Research is published by the International Institute of Anticancer Research
Comparative Analysis of Piazza Navona and Sultanahmet Squares in the Context of Spatial Continuity
No full textBu çalışma, İstanbul'daki Sultanahmet Meydanı ile Roma'daki Piazza Navona'nın mekansal süreklilik bağlamında karşılaştırmalı analizini sunmaktadır. Tarih boyunca farklı kültürlere ev sahipliği yapan bu iki meydan, mimari yapıları, sosyal işlevleri ve sembolik değerleriyle kent kimliğinin oluşumuna katkı sunmuştur. Her iki meydan da, imparatorluk dönemlerinde kamusal yaşamın merkezindeyken, günümüzde turistik, kültürel ve sosyal işlevlerle ön plandadır. Tezde, meydanların tarihsel dönüşümleri, çevre yapı ilişkileri, mekânsal organizasyonları ve günümüz kent yaşamına entegrasyon biçimleri ele alınmıştır. Kentlerin tarihsel sürekliliğini mekansal biçimde sürdürebilen bu alanlar, aynı zamanda kamusal alanın güncel anlamını da yeniden tanımlamaktadır. Karşılaştırmalı analiz, kentlerin sosyo-kültürel evrimiyle birlikte meydanların nasıl yeniden anlamlandığını ve toplumsal hafızadaki yerini koruyarak çağdaş kent yaşamında nasıl var olabildiklerini ortaya koymaktadır.This study offers a comparative analysis of Sultanahmet Square in Istanbul and Piazza Navona in Rome within the framework of spatial continuity. Both squares, having hosted diverse civilizations throughout history, have significantly contributed to the formation of urban identity through their architectural configurations, social functions, and symbolic meanings. While they once served as focal points of public life during imperial eras, they now assume prominent roles as cultural, touristic, and social hubs. The thesis explores the historical transformations of these urban spaces, their relationships with surrounding architectural elements, spatial organizations, and the ways in which they have been integrated into contemporary urban life. As sites that spatially sustain the historical continuity of their respective cities, these squares simultaneously redefine the contemporary conception of public space. The comparative analysis elucidates how such urban spaces have been recontextualized in accordance with the socio-cultural evolution of cities and how they maintain their presence in contemporary urban life by preserving their place within collective memory
Sustainable Energy and Water in Sports Facilities: Success Examples, Certification Processes, and Future Planning
No full textModern teknolojik gelişmelerle birlikte spor tesisleri yalnızca seyirci deneyimiyle değil; Enerji ve su yönetimi açısından da değerlendirilmesi gereken çok boyutlu yapılar olarak görülmektedir. Araştırma kapsamında Türkiye'den yedi stadyum (9 çalışan), iki spor kompleksi (2 çalışan) ve Hollanda'daki bir stadyum (1 çalışan) ile yapılan görüşmeler, sürdürülebilirlik uygulamalarının mevcut durumu ve gelişim potansiyeline ilişkin güncel bir tablo ortaya çıkıyor. Görüşmede, özellikle Bina Yönetim Sistemleri (BMS) gibi teknolojilerin enerji ve su tüketiminin gerçek zamanlı takibinde önemli katkılar sağlanmakta olup, ancak bu sistemlerin henüz yeterli düzeyde olmadığı görülmektedir. Enerji verimliliği açısından, LED aydınlatma ve otomasyon altyapılarının yaygın kullanımı dikkat çekici olsa da su yönetimi uygulamalarının enerjiye kıyasla daha geri planda olduğu ve temel düzeyde olduğu görülmektedir (Görüşme Notları, 2025). Öte yandan, enerji alanında kayda değer değerin hayata geçirildiği de mevcut. Galatasaray Stadyumunun çatısına yerleştirilen 10.404 güneş paneli, 4,2 MW kurulu güç kapasitesiyle istasyonun yıllık elektrik ihtiyacının yaklaşık %63'ünü karşılaması ve yılda 3.250 ton CO₂ emisyonunun korunmasını sağlıyor. Bu proje, 'en yüksek güneş paneli çıkışına sahip istasyonu' olarak Guinness Dünya Rekorları'na sunuldu (Guinness Dünya Rekorları, 2022; Canal Solar, 2022). Sonuç olarak, gerçekçi ve sürdürülebilir bir dönüşüm için, politikaların destekleyici ve başarılı örneklerin ortaya çıkması ve sertifikasyon sistemlerinin bir zorunluluk haline gelmesi gerekmektedir. Anahtar Kelimeler: spor sistemleri, sürdürülebilirlik, enerji yönetimi, su yönetimi, LEED sertifikası, BREEAM sertifikasıWith modern technological advancements, sports facilities are viewed as multidimensional structures that should be evaluated not only in terms of spectator experience but also in terms of energy and water management. Interviews conducted with seven stadiums (9 employees) in Türkiye, two sports complexes (2 employees), and one stadium in the Netherlands (1 employee) as part of the research provide an up-to-date picture of the current status and development potential of sustainability practices. The interviews revealed that technologies such as Building Management Systems (BMS), in particular, make significant contributions to real-time monitoring of energy and water consumption, but these systems are not yet at a sufficient level. While the widespread use of LED lighting and automation infrastructures is noteworthy in terms of energy efficiency, water management practices appear to be more secondary and at a basic level compared to energy management (Interview Notes, 2025). On the other hand, significant value has been implemented in the energy sector. The 10,404 solar panels installed on the Galatasaray Stadium roof, with an installed capacity of 4.2 MW, meet approximately 63% of the station's annual electricity needs and prevent 3,250 tons of CO₂ emissions annually. This project was submitted to Guinness World Records as the 'station with the highest solar panel output' (Guinness World Records, 2022; Canal Solar, 2022).Consequently, for a realistic and sustainable transformation, the emergence of supportive and successful examples of policies and certification systems are essential. Keywords: sports systems, sustainability, energy management, water management, LEED certification, BREEAM certificatio
An Examination of Authenticity and Self-Awareness Among Turkish Immigrants in Germany Based on Their Personality Traits
No full textBu araştırmanın temel amacı, Almanya'da yaşayan farklı kuşak gruplarındaki Türk göçmenlerin (aile birleşimiyle gelen birinci kuşak ile Almanya'da doğan ikinci ve üçüncü kuşak) kişilik özellikleri, otantiklik düzeyleri ve bütünleyici kendilik farkındalıkları arasındaki ilişkileri incelemektir. Araştırma, ilişkisel tarama modeline göre tasarlanmış ve 142 katılımcıdan (68 birinci kuşak, 74 ikinci ve üçüncü kuşak) veri toplanmıştır. Veri toplama aracı olarak Beş Faktör Kişilik Envanteri, Otantiklik Ölçeği ve Bütünleyici Kendilik Farkındalığı Ölçeği kullanılmıştır. Bulgular, Almanya'da doğan ikinci ve üçüncü kuşağın, göç eden birinci kuşağa göre istatistiksel olarak anlamlı düzeyde daha yüksek nevrotiklik düzeyine sahip olduğunu göstermiştir. Ayrıca, Almanya'da doğan kuşakların, birinci kuşağa kıyasla dışsal etkileri daha fazla kabullenme eğiliminde olduğu ve görece daha az otantik olduğu saptanmıştır. Genel olarak otantikliğin en güçlü yordayıcılarının pozitif yönde sorumluluk ve negatif yönde nevrotiklik olduğu belirlenmiştir. Dil yeterliliği incelendiğinde, Almancayı daha akıcı konuşanların kendine yabancılaşma ve dış etkiyi kabullenme düzeylerinin daha yüksek olduğu görülmüştür. Bütünleyici kendilik farkındalığı açısından ise kuşaklar arasında anlamlı bir fark bulunmamıştır. Sonuç olarak, araştırma bulguları göçmen kuşaklar arasında kişilik yapısı ve otantiklik deneyimlerinin farklılaştığını, özellikle Almanya'da doğan neslin artan nevrotiklik ve dışsal etkilere açıklık gibi özelliklerle kültürel uyum ve kimlik çatışması arasında karmaşık bir denge kurduğunu ortaya koymaktadır. Bu durum, göç sonrası psikolojik uyum süreçlerinin çok boyutlu ve kuşaklararası dinamiklerle şekillendiğini vurgulamaktadır.The main objective of this study is to examine the relationships between personality traits, levels of authenticity, and integrative self-awareness among Turkish immigrants in Germany across different generational groups (first generation who came through family reunification and second and third generations born in Germany). The study was designed according to a correlational survey model, and data were collected from 142 participants (68 first generation, 74 second and third generation). The Five-Factor Personality Inventory, Authenticity Scale, and Integrative Self-Awareness Scale were used as data collection tools. The findings showed that the second and third generations born in Germany had statistically significantly higher levels of neuroticism than the first generation who had migrated. Additionally, it was found that the generations born in Germany were more likely to accept external influences and were relatively less authentic compared to the first generation. Overall, it was determined that the strongest predictors of authenticity were positive responsibility and negative neuroticism. When language proficiency was examined, it was observed that those who spoke German more fluently had higher levels of self-alienation and acceptance of external influences. However, no significant difference was found between generations in terms of integrative self-awareness. In conclusion, the research findings reveal that personality structure and experiences of authenticity differ between immigrant generations, particularly that the generation born in Germany has established a complex balance between cultural adaptation and identity conflict, characterized by increased neuroticism and openness to external influences. This situation emphasizes that post-migration psychological adaptation processes are shaped by multidimensional and intergenerational dynamics