Atılım Academic Archive (Atılım University)
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Ultrafast Green Synthesis of Superparamagnetic Hybrid Nanoparticle for Advanced Applications
No full textThe integration of superparamagnetic iron oxide nanoparticles (SPIONs) into functional hybrid nanostructures remains a challenge, particularly in preserving their magnetic properties within composite frameworks. Herein, we present a rapid and environmentally friendly synthesis strategy for SPION-decorated polyhedral oligomeric silsesquioxane (POSS) nanoparticles. The process involves UV-induced polymerization to form POSS nanoparticles, followed by in situ SPION precipitation, with comprehensive characterization performed via SEM, FTIR, XRD, and VSM analyses. This approach enables the fabrication of hybrid nanoparticles (similar to 160 nm) within 5 min and subsequent SPION decoration in under an hour, ensuring (10 emu/g) superparamagnetic behavior. The developed method is highly scalable, efficient, and compatible with green chemistry principles, making it a promising platform for engineering advanced hybrid nanostructures. These nanoparticles hold significant potential for applications in biomedicine, catalysis, and next-generation material science.Turkiye Bilimsel ve Teknolojik Arastirma Kurumu [122C228]This work was supported by the Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (122C228)
An Updated Meta-Analysis on the Association Between Celiac Disease and Cardiovascular Diseases
No full textAsadi Anar, Mahsa/0000-0002-5772-2472Objectives: Research on the relationship between celiac disease (CD) and cardiovascular disease (CVD) is still ongoing, and different studies have reported contradictory findings. To carry out a meta-analysis and systematic review to look into the connection between CD and CVD risk. Methods: A thorough search was conducted in PubMed, Scopus, and Google Scholar databases up to February 19, 2024. Relevant articles were extracted, and the titles, abstracts, and full texts of the related articles were screened. The quality of the studies was assessed using the Joanna Briggs Institute critical appraisal tools. Results: Nine cohort and one case-control studies involving 49,621,333 individuals were included in the meta-analysis. The pooled analysis revealed a 7% increased risk of CVD in CD patients compared to controls (OR: 1.07, 95% CI: 1.03-1.10, P < 0.05). Significant heterogeneity was observed among studies (I2 = 76%, P < 0.001). Conclusion: This meta-analysis provides evidence of a modest but significant increase in CVD risk in patients with CD. The results highlight the importance of considering cardiovascular health in CD treatment and the need for further research to elucidate the mechanisms underlying this association and to develop targeted prevention strategies.Emerging Sources Citation Inde
Robust and Adaptive Control of an Unmanned Aerial Vehicle
No full textBu tezin amacı, bir İnsansız Hava Aracı (İHA) için gürbüz ve uyarlanabilir yönelim ve irtifa kontrolcüleri tasarlamak ve performanslarını değerlendirmektir. Dört rotorlu İHA sistemi kontrolü için geleneksel ve modern kontrol yöntemleri uygulanmıştır. Geleneksel yöntem, Oransal-İntegral-Türevsel kontrolünü ifade ederken, modern yaklaşımlar Aktif Bozulma Reddetme Kontrolü (ADRC) ve Geri Besleme Hatası ile Öğrenme kontrolcüsü içerir. ADRC yaklaşımında, dört rotorlu İHA sisteminin doğrusal olmayan dinamiklerini ele almak için 2. derecen 4. dereceye kadar Genişletilmiş Durum Gözlemcileri kullanılmaktadır. Dört rotorlu İHA davranışını etkili bir şekilde analiz edebilmek için sisteme ait dinamik model geliştirilmiştir. Dört rotorlu İHA sistemi dinamiğinin eksik eyleyici yapısından dolayı modelleme karmaşık bir durum oluşturmaktadır, dört kontrol girdisi on iki durum değişkenini etkiler ve bu durum, öteleme dinamiklerinin rotasyonel dinamikleriyle bağlantılı olmasından kaynaklıdır. Sistem modeli tasarlandıktan sonra kontrol mimarileri oluşturulmuş ve hedeflenen yörüngelerin doğru bir şekilde takip edilmesini sağlamak için kontrol parametreleri atanmıştır. Performans değerlendirmeleri hem kare hem de helizon yörüngeler için gerçekleştirilmiştir. Tasarlanan kontrolcülerin dayanıklılığını değerlendirmek amacıyla, tüm dinamiklere farklı harici bozucular uygulanmıştır. Diğer yandan, kontrolcülerin uyarlanabilirliğini incelemek için sistem parametrelerinde değişiklikler yapılmıştır. Tasarlanan kontrolcülerin harici bozucuları ve parametre belirsizliklerini reddetme performansları, kontrol metrikleri ile analiz edilerek ve yorumlanarak değerlendirilmiştir.The primary objective of this thesis is to design robust and adaptive attitude and altitude controllers for an Unmanned Aerial Vehicle and make assessments on performances. The thesis involves traditional and modern control methods for a quadrotor system. Traditional method implies Proportional-Integral-Derivative (PID) controller while modern approaches include Active Disturbance Rejection Control (ADRC) and Feedback Error Learning (FEL) which implies Artificial Neural Network (ANN) with PID as well as ADRC. The ADRC method substitutes Proportional - Derivative controller and integrates it with the Extended State Observer with an order of 2nd, 3rd and 4th to handle the disturbances and uncertainties. In order to effectively analyse the behaviour of the quadrotor, dynamic model is developed. Due to the underactuated nature of the quadrotor, modelling has a significant challenge, as the four control inputs influence six state variables, with the translational dynamics being coupled with the rotational dynamics. After deriving the system model, controller architectures are constructed, and the control parameters are assigned to enable accurate tracking of desired trajectories. Performance evaluations are conducted for both square and helical trajectories. To assess the robustness of the designed controllers, different external disturbances are applied to all dynamics. On the other hand, to study the adaptivity of them, system parameters variation is tested. The performance evaluation of the designed controllers conducted to make comparison of rejection ability for both external disturbances and parametric uncertainties considering evaluation metrics
Recycling Decommissioned Wind Turbine Blades for Post-Disaster Housing Applications
No full textThe growing adoption of wind energy has resulted in an increasing number of decommissioned wind turbine blades, which pose significant disposal challenges due to their size, material composition, and environmental impact. Recycling these blades has thus become essential. To this aim, this study explores the potential of using recycled wind turbine blades in post-disaster housing applications and examines the feasibility of re-purposing these durable composite materials to create robust, cost-effective, and sustainable building solutions for emergency housing. A case study of a post-earthquake relief camp in Hatay, T & uuml;rkiye, affected by the 2023 earthquake, is used for analysis. First, the energy consumption of thirty traditional modular container-based post-disaster housing units is simulated with a dynamic building simulation tool. Then, the study introduces novel wind turbine blade-based housing (WTB-bH) designs developed using the same simulation tool. The energy consumption of these (WTB-bH) units is compared to that of traditional containers. The results indicate that using recycled wind turbine blades for housing not only contributes to waste reduction but also achieves 27.3% energy savings compared to conventional methods. The novelty of this study is in demonstrating the potential of recycled wind turbine blades to offer durable and resilient housing solutions in post-disaster situations and to advocate for integrating this recycling method into disaster recovery frameworks, highlighting its ability to enhance sustainability and resource efficiency in construction. Overall, the output of this study may help to present a compelling case for the innovative reuse of decommissioned wind turbine blades, providing an eco-friendly alternative to traditional waste disposal methods while addressing critical needs in post-disaster scenarios.Emerging Sources Citation Inde
Expanding the Role of Exosomes in Drug, Biomolecule, and Nanoparticle Delivery
No full textExosomes are nanoscale extracellular vesicles released by diverse cell types, serving essential functions in intercellular communication and physiological processes. These vesicles have garnered considerable interest in recent years for their potential as drug delivery systems, attributed to their natural origin, minimal immunogenicity, high biocompatibility, and capacity to traverse biological barriers, including the blood-brain barrier. Exosomes can be obtained from diverse biological fluids, rendering them accessible and versatile vehicles for therapeutic medicines. This study emphasizes the burgeoning significance of exosomes in drug administration, concentrating on their benefits, including improved stability, target selectivity, and the capacity to encapsulate various biomolecules, such as proteins, nucleic acids, and small molecules. Notwithstanding their potential applications, other problems remain, including as effective drug loading, industrial scalability, and the standardization of isolation methodologies. Overcoming these hurdles via new research is essential for fully harnessing the promise of exosomes in therapeutic applications, especially in the treatment of intricate diseases like cancer and neurological disorders.Science Citation Index Expande
A Comparative Analysis of Subaltern Voices in Chinua Achebe's Things Fall Apart, Paul Scott's the Raj Quartet, and Arundhati Roy's the Ministry of Utmost Happiness
No full textBu tez, Chinua Achebe'nin Things Fall Apart, Paul Scott'un The Raj Quartet ve Arundhati Roy'un The Ministry of Utmost Happiness adlı eserlerindeki 'madun seslerin' karşılaştırmalı bir incelemesidir. Gayatri Chakravorty Spivak'ın maduniyet teorisini bir inceleme aracı olarak kullanan ve sömürgecilik ile maduniyet perspektiflerini merkeze alan bu çalışmada, seçilen romanlardaki karmaşık ve eşitsiz güç dengesi, direniş ve özneleşme süreçleri incelenmektedir. Chinua Achebe'nin Things Fall Apart adlı eserinde, sömürgecilerin yerli İgbo toplumu ile karşılaşması, yoksunluk ve tahakkümün farklı boyutlarıyla anlatılarak, bu karşılaşmanın geleneksel yönetim, din ve kültür sistemlerinin çöküşüne yol açtığı madun deneyimleri betimlenmektedir. Paul Scott'un The Raj Quartet eseri, İngilizlerin Hindistan alt kıtasını işgali sırasında ortaya çıkan karmaşıklıkları, sömürgeci yapıların belirsizliklerini ve sömürgeci hâkimiyete karşı direnişi çok katmanlı bir anlatı yaklaşımıyla temsil etmektedir. Arundhati Roy'un The Ministry of Utmost Happiness eseri ise Hindistan'daki ezilenlerin, özellikle toplumsal cinsiyet, kast ve kültürel aidiyet temelinde yaşadığı baskıların kesişimi ve bu bağlamdaki zorlukları ortaya koymaktadır. Karşılaştırmalı inceleme yöntemi uygulanan çalışmada her bir yazarın, madunların deneyimlerine ve baskıcı kültür, sömürgecilik ve emperyalist ataerkilliği altında ses, temsil ve özneleşme mücadelelerine odaklandığı vurgulanmaktadır. Çalışma, toplumsal cinsiyet, ırk, kast ve sınıf gibi kesişen dinamikleri değerlendirerek, madunların nasıl tahakküm altına alındığını ve susturulduğunu, buna karşılık gelişen direniş ve varlık mücadelesini ortaya koymaktadır. Yakın okuma yöntemiyle, Spivak'ın çağdaş maduniyet söylemindeki madun özneleşmesi anlayışından yararlanan bu çalışma, güç dinamikleri, temsil ve direniş üzerine mevcut alan yazına katkı sunmaktadır.This dissertation is a comparative study of the representation of 'subaltern voices' in Chinua Achebe's Things Fall Apart, Paul Scott's The Raj Quartet, and Arundhati Roy's The Ministry of Utmost Happiness. Using Gayatri Chakravorty Spivak's subaltern theory as a tool, and colonialism and subalternity as significant perspectives, the study sheds light on complex and unequal power balance, resistance and agency in the studied novels. Chinua Achebe's Things Fall Apart depicts the subaltern experience by narrating the colonial encounter with the indigenous Igbo society, an encounter that is riddled with different shades of privation and subjugation, leading to the collapse of their traditional system of governance, religion, culture and so on. Paul Scott's The Raj Quartet, through its multifaceted narrative approach represents the complexities inherent in the British occupation of the Indian subcontinent, the uncertainties in colonial structures, and resistance against colonial dominance. Arundhati Roy's The Ministry of Utmost Happiness portrays the challenges faced by the oppressed in India, highlighting the intersection of dominance and oppression based on gender, caste, and cultural affiliation. With the aid of comparative analysis, the study emphasizes the focus of each writer on subalterns' experiences and their struggle for agency, voice, and representation amidst oppressive rule of culture, colonialism, and imperialist patriarchy. By evaluating the intersectional dynamics of gender, race, caste, and class, this study reveals the different methods through which the subaltern is subjugated, and silenced, and the consequent subaltern resistance and presence. Through a close reading, the study adds value to the existing literature on complex power dynamics, representation, and resistance, drawing from Spivak's view of subaltern agency in the contemporary discourse on subalternity
Detection of Sexually Transmitted Infection Agents in Pregnant Women Using Multiplex Polymerase Chain Reaction Method
No full textBackgroundSexually transmitted infections (STIs) are a significant public health concern that can lead to serious outcomes such as infertility, pregnancy complications, and neonatal infections. This study aimed to evaluate the prevalence of STI and their associated risk factors in symptomatic and asymptomatic pregnant women.MethodsBetween July and October 2024, a total of 300 pregnant women in their third trimester, including 113 symptomatic and 187 asymptomatic individuals aged 18 to 45 years, who sought antenatal care at the Gynecology and Obstetrics Clinic of Ankara Etlik City Hospital, were included in the study. The detection of STIs agents in vaginal swab samples was performed using multiplex polymerase chain reaction in the Molecular Diagnosis Laboratory of the Department of Microbiology.ResultsThe overall prevalence of STIs was 34.3% (103/300), with single and multiple infections accounting for 28.3% and 6.0% of cases, respectively. The most frequently detected pathogens were Ureaplasma parvum/urealiticum (29.0%), Mycoplasma hominis (4.6%), and Chlamydia trachomatis (2.3%). Co-infections were commonly observed between Ureaplasma parvum/urealiticum and Mycoplasma hominis. No significant difference in STI prevalence was observed between the symptomatic (35.4%) and asymptomatic (33.7%) groups. Co-infection with non-STI bacterial agents, such as Gardnerella vaginalis and Streptococcus agalactiae, increased the risk of STIs by 1.96 times (p = 0.006).ConclusionsThis study revealed that STIs occur at similar rates among symptomatic and asymptomatic pregnant women. This finding highlights the critical importance of detecting asymptomatic cases to prevent the spread of silent infections and to safeguard maternal and neonatal health. Ureaplasma parvum/urealiticum were identified as the most common pathogens. Given that co-infections with non-STI bacterial agents significantly increase the risk of STIs, multiplex PCR-based multicenter and prospective studies are essential to refine screening strategies for pregnant women.Science Citation Index Expande
Is It Just to Violate Sovereign Rights Through Responsibility to Protect? A Study on Contradictions Between the Principles and Practices of the Responsibility to Protect Norm
No full textBu tez devlet egemenliği ilkesinin hala uluslararası sistemin zeminini oluşturduğu bir ortamda, insani müdahalelerin ahlaki ve hukuki açıdan haklı sayılıp sayılamayacağını incelemektedir. Kosova ve Libya gibi krizler incelenerek, insani müdahale söylemlerinin nasıl kullanıldığını ve bu söylemlerin çoğu zaman siyasi çıkarlarla, güç dengeleriyle ve uluslararası ilişkilerde 'adil' ya da 'kabul edilebilir' sayılan kavramlarla nasıl örtüştüğünü ortaya koymaktadır. 'Müdahale etmek haklı mıdır?' sorusuna bir perspektif sunmayı amaçlamaktadır. Hukukun normatif doğası ile uluslararası ilişkilerin yoruma açık yapısı arasındaki çelişkiyi ele alırken eleştirel yapısalcılık yaklaşımından yararlanmaktadır. Siyaset teorisi ve uluslararası hukuk alanlarındaki temel tartışmalardan yola çıkarak, kitlesel acılar ve insan hakları ihlallerinde gerçekleşen dış müdahalelerin meşruiyetini analiz etmektedir. Bu tez, Koruma Sorumluluğu (R2P) ilkesine dair tartışmalar ve değişmekte olan insani müdahale uygulamalarına odaklanarak, bu değişimlerin hukuki ve siyasi düzeni nasıl yeniden şekillendirmeye çalıştığını anlamaya çalışırken, Michael Walzer'ın Haklı Savaş yaklaşımını eleştirmekte ve öte yandan da Koruma Sorumluluğu normunun, ilkeleri ile uygulanması arasındaki farklılıklara vurgu yapmaktadır.This thesis examines the question of whether humanitarian intervention can be considered both morally and legally just in an international system that continues to be defined by the principle of state sovereignty. By examining crises such as Kosovo and Libya, the thesis questions and argues how humanitarian intervention has been invoked, and how such claims often overlap with political interests, unequal power relations, and shifting notions of what is considered acceptable or just in international affairs. This thesis claims to offer a perspective on the question of 'is it just to intervene?'. It explores the contradiction between the normative nature of law and the interpretive nature of international relations as a social science through critical constructivism. It engages with key debates in political theory and international law to analyse the legitimacy of foreign interventions in cases involving mass atrocities and human rights violations. The thesis focuses on debates on the Responsibility to Protect and evolving humanitarian practices to understand how these frameworks seek to reorganise the legal and political frameworks while criticising Michael Walzer's Just War Tradition and the practical differences between the principles and implementation of the R2P norm
Analysis of the Structural and Optical Characteristics of Znse Thin Films as Interface Layer
No full textThis research reveals the results of a comprehensive analysis of the optical and structural features of zinc selenide (ZnSe) thin film. The studied film was synthesized using the thermal evaporation method after preparation on the glass substrate. The film’s structural characteristics, which have been determined by using scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD), confirm the polycrystalline nature of the films with a predominant cubic zinc-blende structure. The surface morphology investigated through SEM reveals a uniform grain distribution with minimal surface defects, indicating high-quality film formation. In order to examine the optical characteristics, the ultraviolet–visible spectroscopy method is used in a spectral range between 300 and 900 nm. In this way, the ultraviolet–visible spectroscopy data are utilized to obtain optical features such as extinction coefficient (k), optical band gap (Eg), refractive index (n), absorption coefficient (α), and optical conductivity (σopt). These optical properties are assessed using ultraviolet–visible spectroscopy, revealing a direct band gap of approximately 2.88 eV, which is consistent with the bulk properties of ZnSe and suitable for optoelectronic applications. The results of this study clearly show that the studied ZnSe film can be used for optoelectronic device applications. © The Author(s) 2025.Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK; Scientific Research Projects Office of Gazi University, (FUİ-2023-8680)Science Citation Index Expande
The Dark Side of Proactive Behaviors and Blind Spot Management
No full textProactive behavior, which should be anticipatory and agentic, can be defined as actions focused on certain behaviors aimed at improving job performance, career success, and employee well-being. Even if organizational citizenship behaviors have been frequently characterized as proactive behaviors, this is not true under every condition, as they may be either reactive or passive. Although proactive behavior among employees has been widely studied because of the importance that organizations place on improving performance and effectiveness, the potential and possible negative outcomes of such behavior have often been ignored. Examining and discovering the potential negative implications of proactive behaviors and formulating strategies to manage blind spots are vital for developing a general understanding of proactive behaviors for both employees and firms. The intention of this study is to conduct a literature review on proactive behaviors by focusing on the dark side and blind spots of proactive behaviors. This chapter also explains various forms of proactive behaviors and theories that can effectively describe the negative outcomes of such behaviors and discusses the detrimental effects of proactive behaviors on both employees and organizations. © 2025 The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG