WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394
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Article Surface Integrity and Tool Wear in S2-GFRP Milling: Experimental and Statistical Evaluation of Cutting Parameters and DLC and TiAlN Tool Coatings(Springer London Ltd, 2026) Danisman, Sengul; Yilmaz, Cagatay; Ersoy, Emin; Kesriklioglu, SinanIn this study, the surface integrity of S2-glass fiber-reinforced polymer (S2-GFRP) composites during milling with carbide cutters was investigated using a two-phase experimental design, focusing on surface roughness (Ra), burr area, and tool wear (VB). In the first phase, using a Taguchi L9 design, the effects of coating type (uncoated, TiAlN, DLC), spindle speed (2000-6000 rpm), and feed rate (0,15-0,25 mm/rev) on Ra and burr area were evaluated. In this short machining range where tool wear was negligible, the optimal combination yielding the lowest Ra (approximate to 0.97 mu m) and the minimum burr area (approximate to 231 mm & sup2;) was determined to be 4000 rpm, 0,15 mm/rev, and the DLC-coated tool. Regarding the effect of tool material on Ra, the DLC-coated tool provided approximately 4 and 2 times better results than the uncoated and TiAlN-coated tools, respectively. In the second phase, experiments extended up to 130 passes with this optimal parameter set showed that Ra increased significantly with increasing VB, and the burr area exhibited threshold-like behavior. In particular, a sudden increase in Ra and the burr area was observed when the VB approximate to threshold of approximately 100 mu m was exceeded; partial regression analyses confirmed different burr-formation tendencies in the low- and high-wear regimes. The results reveal that DLC coating initially provides superior performance in S2-GFRP milling, but surface degradation accelerates after the critical VB threshold.Article From Agility to Advocacy: Exploring How Gender Moderates the Impact of Social Media Agility on Brand Trust and Influencing Behavior(Palgrave Macmillan Ltd, 2026) Bozkurt, Sıddık; Gligor, David; Hollebeek, Linda D.; Sarp, SerapThis research investigates the effect of perceived social media agility (P-SMA) on customers' influencing behavior, a theoretical subset of engagement behavior, with brand trust acting as a mediator and gender (male/female) as a moderator. It also explores how these relationships differ across age groups. Two online surveys were conducted: Study 1 with 165 younger participants and Study 2 with 178 adults. Using PROCESS Macro Models 4 and 7, we tested direct, mediated, and moderated mediation effects. Both studies found that P-SMA enhances brand trust, which subsequently mediates its influence on customer behavior. Study 2 confirmed these results, showing that gender moderates the relationship between P-SMA and both brand trust and influencing behavior, with stronger effects observed among females (vs. males) in both samples. The findings highlight the importance of tailoring social media strategies to gender-based engagement patterns. Crafting content and interaction styles that foster trust can improve influence and advocacy, especially when agility is a key element of the brand's digital presence. This research integrates P-SMA, brand trust, and customer influence behavior within a moderated mediation model. Using two age-diverse samples, it shows gender shapes reactions to brand agility, while age differences remain non-significant across both datasets.Article Dissecting the Strain and Sex Specific Connectome Signatures of Unanesthetized C57BL/6J and DBA/2J Mice Using Magnetic Resonance Imaging(Wiley, 2026) Neuberger, Thomas; Kamens, Helen M.; Zhang, Nanyin; Ünsal, Hayreddin Said; Arefin, Tanzil M.Mouse models are an essential tool for understanding behavior and disease states in neuroscience research. While genetic and sex-specific effects have been reported in many neurodegenerative and psychiatric illnesses, these factors may also alter baseline neuroanatomical features of mice. This raises the question of whether the observed changes are related to the disease being studied (i.e., pathological differences) or if there are baseline strain or sex differences that may predispose animals to different responses. Over the past decade, tremendous effort has been made to map neural architecture at various scales; however, the complex relationships, including identifying genetic and sex-specific differences in brain structure and function, remain understudied. To bridge this gap, we used C57BL/6J and DBA/2J mice, two of the most widely used inbred mouse strains in neuroscience research, to investigate strain and sex-specific features of the brain connectome in awake animals using magnetic resonance imaging (MRI). By combining resting-state functional MRI and diffusion MRI, we found that the motor, sensory, limbic, and salience networks exhibit significant differences in both functional and structural domains between C57BL/6J and DBA/2J mice. Further, functional and structural properties of the brain were significantly correlated in both strains. Our results underscore the importance of considering these baseline differences when interpreting brain-behavior interactions in mouse models of human disorders.Article Novel Statistical Approaches for Survival Analysis of RNA-Sequencing Data(Bentham Science Publ Ltd, 2026) Cephe, Ahu; Karabulut, Erdem; Zararsız, Gözde Ertürk; Sezgin, Ahmet; Koçhan, NeclaIntroduction/Objective Accurate patient survival predictions are vital for effective cancer treatments. Precision medicine uses gene expression data to improve prognosis by considering genetic variability. Predicting survival in cancer patients using high-dimensional gene expression data, such as RNA-sequencing (RNA-seq), attracted much attention in recent years. However, the literature contains limited algorithms for survival modeling that account for the high dimensionality, heterogeneity, and correlated genes of RNA-seq data. This study aims to develop novel approaches for predicting survival and identifying biomarkers using RNA-seq data.Introduction/Objective Accurate patient survival predictions are vital for effective cancer treatments. Precision medicine uses gene expression data to improve prognosis by considering genetic variability. Predicting survival in cancer patients using high-dimensional gene expression data, such as RNA-sequencing (RNA-seq), attracted much attention in recent years. However, the literature contains limited algorithms for survival modeling that account for the high dimensionality, heterogeneity, and correlated genes of RNA-seq data. This study aims to develop novel approaches for predicting survival and identifying biomarkers using RNA-seq data.Methods Survival data of RNA-seq is first transformed into binary classification data using a stacking algorithm. Then, block-based priority-Lasso and IPF-Lasso algorithms are applied to the dataset, which includes two distinct types of variables. Additionally, sample weights obtained from the voom transformation are incorporated. Our approaches, named voomStackLasso, are tested on 12 real datasets from the TCGA database. We used Harrell's concordance index and the integrated Brier score to evaluate model performance, and the number of selected features to assess model sparsity.Results The results indicated that the voomStackLasso algorithms demonstrated comparable or superior performance compared to other existing survival algorithms. Furthermore, we have introduced an R package called MLSeqSurv, which allows for the utilization of both established survival algorithms from the literature and voomStackLasso algorithms for RNA-seq data.Conclusion This study introduces two new algorithms for the survival analysis of RNA-seq data. Additionally, this study has led to new research directions for applying both existing and newly developed classification algorithms to the survival analysis of RNA-seq data.Article Failure Mechanisms and Damage Evolution of Geopolymer Concrete Beams under Flexural Loading: Experimental Investigation and Finite Element Analysis(SAGE Publications Inc, 2026) Ozbayrak, Ahmet; Aslanbay, Yuksel Gul; Aslanbay, Huseyin Hilmi; Altun, Fatih; Kucukgoncu, HurmetThis study investigates the failure behavior and damage mechanisms of geopolymer concrete (GPC) and ordinary Portland cement (OPC) reinforced concrete beams through a combined experimental and numerical approach. Flexural tests were conducted, and then displacement and crack development were monitored using high-precision total station measurements. Numerical analyses were performed using ABAQUS, and the consistency between experimental observations and numerical predictions was evaluated at yield and failure stages to characterize inelastic behavior and damage progression. The effects of key parameters, including tensile reinforcement ratio, geopolymer concrete formulations, and curing methods, on cracking behavior, stiffness degradation, and failure modes were investigated in detail. The results indicate that increasing the tensile reinforcement ratio enhances flexural stiffness and load-bearing capacity while reducing ductility at advanced damage stages. Compared to OPC beams, GPC beams exhibited narrower and more distributed crack patterns due to their distinct microstructural characteristics. Quantitatively, GPC beams exhibited approximately 15% greater deformation in the compression zone at failure, while tensile reinforcement strains were up to 23% higher at yield compared to OPC beams. In addition, the maximum crack width at failure in GPC beams was approximately 50% lower than that of OPC beams. These results indicate that, despite similar strength levels, GPC beams exhibit higher deformation capacity and more distributed damage behavior. The findings demonstrate that geopolymer concrete exhibits distinct failure characteristics compared to OPC and should be explicitly considered in structural design to improve damage control and failure prediction. Overall, the study highlights the potential of geopolymer concrete as a reliable and sustainable structural material.Article Comparison of Rapamycin and 3-Methyladenine in Cisplatin-Induced Experimental Cardiotoxicity(Wiley, 2026) Kaymak, Emin; Karabulut, Derya; Yalcin, Betul; Guner, Serife Ayaz; Ozturk, Emel; Findik, Fatma; Boyvat, DuduIn this study, we evaluated how cisplatin cardiotoxicity affects the histological and endocrine functions of the heart and autophagy while using Rapamycin(Rapa) and 3-methyladenine(3-MA) as autophagy activators and inhibitors. Control, Cisplatin (Cis), 3-methyladenine + Cisplatin (3-MA + Cis) and Rapamycin + Cisplatin (Rapa + Cis). Rapa and 3-MA were administered for 15 days, while a single dose of cisplatin was administered on the 7th day. Natriuretic peptide receptor-A(NPR-A), receptor-B(NPR-B) and biochemically atrial natriuretic peptide(ANP) and brain natriuretic peptide(BNP) levels were evaluated in heart tissue. Cis caused a statistically significant increase in NPR-A and NPR-B expression, as well as ANP and BNP levels. However, the levels of Beclin-1 and LC3B were not statistically significant. Rapa was more effective than 3-MA + Cis on NPR-A and NPR-B expressions, but did not show the same effect on ANP and NT-proBNP levels. Cis caused an increase in Beclin-1 and LC3B levels, while a decrease was observed in both 3-MA + Cis and Rapa + Cis groups. Our results revealed that Cis cardiotoxicity disrupts autophagy and endocrine function of the heart. It was concluded that by continuing the activator and inhibitor substances after Cis application, more effective results can be obtained in Beclin-1 expression than LC3B expression and that they can be effective in eliminating the toxicity of Cis.Article Modal Characteristics of Fly Ash-Based Geopolymer Reinforced Concrete Columns under Dynamic Impact Loads(Techno-Press, 2026) Kucukgoncu, HurmetGeopolymer concrete (GPC) stands out as an environmentally friendly, sustainable structural material with superior mechanical and thermal properties, as an alternative to ordinary Portland cement (OPC) concrete. Due to this, investigating the dynamic properties of GPC materials is particularly crucial for structures subjected to vibration loads such as earthquakes. Therefore, eight heat-cured class F fly ash-based GPC and two OPC column specimens were subjected to modal tests using the Experimental Modal Analysis (EMA) method. Thus, the modal characteristics of columns produced from GPC were investigated and compared regarding reinforcement ratio, alkali activator ratio, and curing method. Furthermore, the dynamic properties of GPC and OPC columns were also compared. Additionally, the relationship between these columns' resonance frequencies, damping ratios, mode shapes, and mechanical properties was evaluated. The results show that although the resonance frequencies of OPC columns are 8.19% higher than those of GPC columns, their damping ratios are 13.01% lower. For GPC columns, the alkali activator ratio and curing method had a greater impact on the modal characteristics of the column samples than the reinforcement ratio. Besides, the relationship between strength and resonance frequency was closely related. In contrast, the damping ratio was closely related to the static modulus of elasticity and rigidity values. In particular, it was concluded that GPC columns had higher energy dissipation capacities, which was an important design parameter, under dynamic loads due to the high damping ratio.Article Enhanced Mg–Zn–Ca Alloys Reinforced with Rare Earth Oxides for Biomedical Applications: Experimental Insights and ANFIS-Based Modeling(Springer, 2026) Mozafari, Farzin; Deka, Surja; Mallick, AshisTo enhance the corrosion resistance, biocompatibility, tribological, and mechanical properties of magnesium (Mg) alloys intended for biomedical implants, a new approach utilizing a microwave-sintered in situ hot extrusion-based powder metallurgy process was used to develop Mg-4Zn-0.5Ca/xCeO2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_2$$\end{document} (x = 0.5, 1, and 1.5 vol%) nanocomposites. The introduction of ceria nanoparticles (CONPs) has improved the compression characteristics of the nanocomposites in comparison with the monolithic Mg, and the ternary base alloy. The corrosion test results revealed that the alloy and nanocomposites promoted the formation of the magnesium hydroxide (Mg(OH)2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_2$$\end{document}) and hydroxyapatite (HA) layers on the sample surface. Among all samples, Mg-4Zn-0.5Ca /1.0CeO2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_2$$\end{document} demonstrated the lowest corrosion rate. In vitro cytocompatibility assessments were conducted through an extract assay method for different time periods, employing MG-63 cells. The developed alloy and nanocomposites demonstrated no harmful effects on MG-63 cells. An investigation into the dry sliding tribological characteristics of the alloy and nanocomposites at varied loads revealed several wear mechanisms, including abrasion, adhesion, delamination, oxidation, and plastic deformation. The addition of CONPs significantly enhanced the wear resistance of the nanocomposites. Our results provide a new venue to enhance the biocompatibility and in vitro degradation behavior of well-established Mg-Zn-Ca alloys, with a particular focus on the mechanical integrity of the developed samples for their clinical usage. An Adaptive Neuro-Fuzzy Inference system (ANFIS)-based modeling approach was also developed to individually characterize nanocomposite corrosion, cell viability, and wear behavior. The predictions offer compelling evidence of the reliability and accuracy of the proposed modeling strategy.Article Environmental Sustainability in Fragile States: The Role of Corruption Control, Political Stability, and Household Consumption in Somalia(Springer, 2026-03-28) Mohamed, Amir Mohamud; Warsame, Abdimalik Ali; Dirie, Khadar AhmedThe maintenance of environmental sustainability represents a worldwide pressing issue, especially for Somalia as an emerging nation that deals with environmental degradation because of unstable political leadership combined with corruption and financial limitations. This study analyzes the impact of corruption control, political stability, and household consumption on environmental degradation in Somalia. The study employs the kernel regularized machine learning method (KRLS) and a time-varying Granger causality approach. The KRLS addresses regression and classification tasks without depending on assumptions of linearity or additivity, whereas the time-varying Granger causality fixes instabilities caused by structural breaks, regime shifts, and provides a cause-effect relationships for specific years. The empirical results of the KRLS indicate that corruption control enhances environmental quality by reducing environmental degradation, whereas household consumption impedes it. Additionally, political stability has no discernible impact on environmental degradation. The time-varying Granger causality result revealed no significant causality from corruption control to environmental degradation in the forward and rolling windows. Two episodes of Granger causalities (2009-2011 and 2013-2016) are observed from corruption control to environmental degradation, and one episode of causality (2001-2004) from political stability to environmental degradation was detected in the recursive result. Finally, four episodes of causalities (2005-2007, 2008-2011, and 2014-2015) are observed from household consumption to environmental degradation in Somalia in the recursive result. This could be justified by the fact that climate consequences-droughts and floods-inhibit livelihood sources such as livestock and agriculture. Hence, people put pressure on forests in search of alternative income sources. Nevertheless, the study delivers practical recommendations to policymakers about using governance structures and economic decisions along with institutional mechanisms for creating sustainable environmental practices.Article A Conceptual Framework for Social Sustainability in Facade Design(Taylor & Francis Ltd, 2026-04-04) Utkan, Muharrem Melih; Metin, BuketThis research examines how participatory design can be used to bring social sustainability principles into the facade design industry, where technical and economic priorities often dominate. Drawing on a review of literature and five semi-structured interviews with architects, facade consultants, and facade system designers in Türkiye, the study identifies recurring gaps in timing, collaboration, and responsibility that limit the consideration of social sustainability criteria. These gaps are then used as the basis for a conceptual framework that maps social sustainability principles across the phases of facade design and specifies points where participatory methods could make a difference. The conceptual framework is intended as an exploratory step: it does not offer universal rules, but a structured way of thinking about where and how participation can be introduced in a fragmented and highly technical design process. The contribution lies in extending participatory design research into a specialized design industry context and showing how social sustainability can be translated from broad principles into practical interventions. While the study is based on a small sample and situated within the Turkish industry, the approach points to opportunities for further testing and adaptation in other design environments where collaboration is limited and social concerns remain underdeveloped.