Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Novel Strut-Based Mechanical Analysis: Flow Stress Determination of Electron Beam Melt (EBM) Lattice Structures(Springernature, 2025) Bin Riaz, Muhammad Arslan; Erten, Hacer Irem; Guden, MustafaIn modeling lattices, the material flow stress equation, such as the Johnson and Cook (JC) equation, is usually determined from the mechanical tests conducted on bulk, relatively large test size specimens which were manufactured using the same process parameters with the lattices. However, the flow stresses of struts were shown in several studies to be significantly lower than those of large size test specimens. To overcome this discrepancy, a novel approach that combined the strut compression test, the strut double shear test (DST) and the numerical model of the strut DST using the JC equation was proposed. The study confirmed that the flow stress determined from the machined bulk tension test specimens overestimated the experimental compression stress-strain behavior of a body centered cubic (BCC) Ti6Al4V lattice. The flow stress parameters determined from the compression stress-strain curves of the as-printed strut specimens, on the other side, showed the best match to the experimental compression stress-strain behavior of the BCC lattice. The fidelity of the determined parameters of the JC equation was further verified with the experimental and numerical DSTs. It was also shown that the numerical iterations of DST model could be used for the fine-tuning the flow stress parameters.Article Meal Timing Trajectories in Older Adults and Their Associations With Morbidity, Genetic Profiles, and Mortality(Springernature, 2025) Dashti, Hassan S.; Liu, Chloe; Deng, Hao; Sharma, Anushka; Payton, Antony; Maharani, Asri; Didikoglu, AltugBackgroundOlder adults are vulnerable to mistimed food intake due to health and environmental changes; characterizing meal timing may inform strategies to promote healthy aging. We investigated longitudinal trajectories of self-reported meal timing in older adults and their associations with morbidity, genetic profiles, and all-cause mortality.MethodsWe analyzed data from 2945 community-dwelling older adults from the University of Manchester Longitudinal Study of Cognition in Normal Healthy Old Age, with up to five repeated assessments of meal timing and health behaviors conducted between 1983 and 2017. Linear mixed-effects models, latent class analysis, and Cox regression were used to examine relationships between meal timing with illness and behavioral factors, genetic scores for chronotype and obesity, and mortality.ResultsHere we show older age is associated with later breakfast and dinner times, a later eating midpoint, and a shorter daily eating window. Physical and psychological illnesses, including fatigue, oral health problems, depression, anxiety, and multimorbidity, are primarily associated with later breakfast. Genetic profiles related to an evening chronotype, but not obesity, are linked to later meals. Later breakfast timing is also associated with increased mortality. Latent class analysis of meal timing trajectories identify early and late eating groups, with 10-year survival rates of 86.7% in the late eating group compared to 89.5% in the early eating group.ConclusionsMeal timing, particularly later breakfast, shifts with age and may reflect broader health changes in older adults, with implications for morbidity and longevity.Article A Comprehensive MicroRNA-Seq Transcriptomic Analysis of Tay-Sachs Disease Mice Revealed Distinct MiRNA Profiles in Neuroglial Cells(Springernature, 2025) Kaya, Beyza; Orhan, Mehmet Emin; Yanbul, Selman; Demirci, Muserref Duygu Sacar; Demir, Secil Akyildiz; Seyrantepe, VolkanTay-Sachs disease (TSD) is a rare lysosomal storage disorder marked by the progressive buildup of GM2 in the central nervous system (CNS). This condition arises from mutations in the HEXA gene, which encodes the alpha subunit of the enzyme beta-hexosaminidase A. A newly developed mouse model for early-onset TSD (Hexa-/-Neu3-/-) exhibited signs of neurodegeneration and neuroinflammation, evidenced by elevated levels of pro-inflammatory cytokines and chemokines, as well as significant astrogliosis and microgliosis. Identifying disease-specific microRNAs (miRNAs) may aid the development of targeted therapies. Although previous small-scale studies have investigated miRNA expression in some regions of GM2 gangliosidosis mouse models, thorough profiling of miRNAs in this innovative TSD model remains to be done. In this study, we employed next-generation sequencing to analyze the complete miRNA profile of neuroglial cells from Hexa-/-Neu3-/- mice. By comparing KEGG and Reactome pathways associated with neurodegeneration, neuroinflammation, and sphingolipid metabolism in Hexa-/-Neu3-/- neuroglial cells, we discovered new microRNAs and their targets related to the pathophysiology of GM2 gangliosidosis. For the first time, our findings showed that miR-708-5p, miR-672-5p, miR-204-5p, miR-335-5p, and miR-296-3p were upregulated, while miR-10 b-5p, miR-615-3p, miR-196a-5p, miR-214-5p, and miR-199a-5p were downregulated in Hexa-/-Neu3-/- neuroglial cells in comparison to age-matched wild-type (WT). These specific changes in miRNA expression deepen our understanding of the disease's neuropathological characteristics in Hexa-/-Neu3-/- mice. Our study suggests that miRNA-based therapeutic strategies may improve clinical outcomes for TSD patients.Article Citation - WoS: 1Citation - Scopus: 1The Role of Trna Fragments on Neurogenesis Alteration by H2o2-Induced Oxidative Stress(Springernature, 2025) Karacicek, Bilge; Katkat, Esra; Binokay, Leman; Ozhan, Gunes; Karakulah, Goekhan; Genc, SerminTransfer RNAs (tRNAs) are small non-coding RNA molecules transcribed from tRNA genes. tRNAs cleaved into a diverse population tRNA fragments (tRFs) ranging in length from 18 to 40 nucleotides, they interact with RNA binding proteins and influence the stability and translation. Stress is one of the reasons for tRFs cleavage. In our study, we modeled oxidative stress conditions with hydrogen peroxide (H2O2) exposure and dealt with one of the frequently expressed tRF in the hippocampus region of the brain, which is tRF-Glu-CTC. For this purpose, neural stem cells (NSCs) were exposed to H2O2, and tRF-Glu-CTC levels were increased in various H(2)O(2 )concentrations. A decrease was seen in microtubule-associated protein 2 (MAP2) marker expression. To understand the H(2)O(2)oxidative stress condition on the expression of tRNA fragments, 72 hpf zebrafish embryos exposed to different H(2)O(2 )concentrations, an increase in the level of tRF-Glu-CTC was observed in all concentrations of H(2)O(2 )compared to control. Subsequently, neurogenesis markers were figured out via Calb2a (calbindin 2a) in situ hybridization (ISH) and HuC/D immunofluorescence staining (IF) staining experiments. Under H(2)O(2 )exposure, a decline was observed in Calb2a and HuC/D markers. To understand the inhibitory role of tRF-Glu-CTC on neurogenesis, NSCs were transfected via tRF-Glu-CTC inhibitor, and neurogenesis markers (ss III-tubulin, MAP2, and GFAP) were determined with qRT-PCR and IF staining. tRF-Glu-CTC inhibitor reversed the diminished neuronal markers expression under the exposure of H2O2. Gene Ontology (GO) enrichment analysis showed us that targets of tRF-Glu-CTC are generally related to neuronal function and synaptic processes.Article Citation - WoS: 1Tcgex: a Powerful Visual Interface for Exploring and Analyzing Cancer Gene Expression Data(Springernature, 2025) Kus, M. Emre; Sahin, Cagatay; Kilic, Emre; Askin, Arda; Ozgur, M. Mert; Karahanogullari, Gokhan; Ekiz, H. AtakanAnalyzing gene expression data from the Cancer Genome Atlas (TCGA) and similar repositories often requires advanced coding skills, creating a barrier for many researchers. To address this challenge, we developed The Cancer Genome Explorer (TCGEx), a user-friendly, web-based platform for conducting sophisticated analyses such as survival modeling, gene set enrichment analysis, unsupervised clustering, and linear regression-based machine learning. TCGEx provides access to preprocessed TCGA data and immune checkpoint inhibition studies while allowing integration of user-uploaded data sets. Using TCGEx, we explore molecular subsets of human melanoma and identify microRNAs associated with intratumoral immunity. These findings are validated with independent clinical trial data on immune checkpoint inhibitors for melanoma and other cancers. In addition, we identify cytokine genes that can be used to predict treatment responses to various immune checkpoint inhibitors prior to treatment. Built on the R/Shiny framework, TCGEx offers customizable features to adapt analyses for diverse research contexts and generate publication-ready visualizations. TCGEx is freely available at https://tcgex.iyte.edu.tr, providing an accessible tool to extract insights from cancer transcriptomics data.Article Exploring Women's Visceral Engagement With Electric Appliances in Turkish Kitchens(Springernature, 2025) Emgin, Bahar; Karaosmanoğlu, Defne; Ata, Leyla Bektaş; Karaosmanoglu, Defne; Ata, Leyla Bektas; Emgin, BaharThis paper investigates the narratives and experiences of women regarding cooking with small electric appliances. It intends to offer a novel perspective on gender and technology studies by foregrounding the visceral dimensions of these encounters. Drawing from a larger project on the historical representations and lived experiences of domestic technologies in Turkey, it highlights how the embodied dimensions of cooking shape the ways women perceive, adapt, and integrate technology into their daily lives. This study is based on interviews with twenty-seven women across five cities in Turkey conducted between 2022 and 2024. While small electric appliances are often marketed for convenience and efficiency, we argue that focusing solely on their instrumental benefits neglects the complex and visceral ways women engage with technology. A visceral approach remains an undervalued lens for understanding these interactions, particularly as women's embodied knowledge and relationships to kitchen appliances challenge scholarship that prioritizes progress and efficiency. As active agents, many women resist these technologies, viewing them as misaligned with the embodied knowledge and practices integral to cooking. By reevaluating the relationship between food, gender, and technology, we propose that such disengagement challenges the positivist reliance on science and technology, emphasizing the importance of embodied knowledge and everyday practices in shaping women's interactions with technology.Article Citation - WoS: 2Citation - Scopus: 2Origami-Inspired Microfluidic Paper-Based Analytical Device (μpad) for Microorganism Detection(Springernature, 2024) Sozmen, A. Baran; Bayraktar, A. Ezgi; Arslan-Yildiz, AhuPathogenic microorganisms impose great risk especially in resource-limited settings due to inaccessibility of diagnostic tools and monitoring devices. This is mainly caused by current methods often being economically demanding and complex in practice; while these methods are sensitive and accurate, they rarely follow Point-of-care (POC) approaches, which is essential for rapid detection and intervention. Incorporating origami into paper-based analytical devices (mu PAD) presents an innovative alternative, offering affordability, portability, and ease of disposal. Herein, a colorimetric origami mu PAD that is suitable for use in POC applications was developed. The mu PAD was fabricated via laser ablation utilizing PVDF and cellulose membranes. In order to develop the biosensor platform, fabrication parameters were optimized and hydrophilicity of PVDF membranes was improved using various solvents. The PVDF membranes were characterized through light microscopy imaging, protein adsorption assay and contact angle measurements. Then, optimization of the assay parameters was carried out in order to improve sensitivity and resolution of the mu PAD, utilizing Box-Behnken experimental design. The responses generated by the origami mu PAD in form of visible color development were then analyzed using image processing. After optimization is concluded, E. coli detection was carried out as a model system. Resulting calculations showed a limit of detection (LoD) of 2 CFU/mL and a dynamic working range up to 106 CFU/mL for E. coli. Overall, developed origami mu PAD promises an economic advantage compared to conventional methods, and provides rapid and sensitive results without the requirement of expertise or complex equipment.Review Citation - WoS: 7Citation - Scopus: 8Magnetic Levitation-Based Miniaturized Technologies for Advanced Diagnostics(Springernature, 2024) Karakuzu, Betul; Inevi, Muge Anil; Tarim, E. Alperay; Sarigil, Oyku; Guzelgulgen, Meltem; Kecili, Seren; Tekin, H. CumhurTaking advantage of the magnetic gradients created using magnetic attraction and repulsion in miniaturized systems, magnetic levitation (MagLev) technology offers a unique capability to levitate, orient and spatially manipulate objects, including biological samples. MagLev systems that depend on the inherent diamagnetic properties of biological samples provide a rapid and label-free operation that can levitate objects based on their density. Density-based cellular and protein analysis based on levitation profiles holds important potential for medical diagnostics, as growing evidence categorizes density as an important variable to distinguish between healthy and disease states. The parallel processing capabilities of MagLev-based diagnostic systems and their integration with automated tools accelerates the collection of biological data. They also offer notable advantages over current diagnostic techniques that require costly and labor-intensive protocols, which may not be accessible in a low-resource setting. MagLev-based diagnostic systems are user-friendly, portable, and affordable, making remote and label-free applications possible. This review describes the recent progress in the application of MagLev principles to existing problems in the field of diagnostics and how they help discover the molecular- and cellular-level changes that accompany the disease or condition of interest. The critical parameters associated with MagLev-based diagnostic systems such as magnetic medium, magnets, sample holders, and imaging systems are discussed. The challenges and barriers that currently limit the clinical implications of MagLev-based diagnostic systems are outlined together with the potential solutions and future directions including the development of compact microfluidic systems and hybrid systems by leveraging the power of deep learning and artificial intelligence.Article Citation - WoS: 1Citation - Scopus: 1Fractional Duals of the Poisson Process on Time Scales With Applications in Cryptography(Springernature, 2024) Gharari, Fatemeh; Hematpour, Nafiseh; Bakouch, Hassan S.; Popovic, Predrag M.A super-structure system for probability densities, covering not just typical types but also fractional ones, was developed using the time scale theory. From a mathematical point of view, we discover duals of the Poisson process on the time scale T=R\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathbb {T}=\mathbb {R}$$\end{document} for the time scales T=Z\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathbb {T}=\mathbb {Z}$$\end{document} and T=qZ,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathbb {T}=q<^>{\mathbb {Z}},$$\end{document} evaluating del-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\nabla -$$\end{document}calculus and Delta-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Delta -$$\end{document}calculus. Also, we search the fractional extensions of the Poisson process on these time scales and detect duals of them. A simulation allows for comparing the nabla and delta types of the observed distributions, not just typical types but also fractional ones. As an application, we also propose new substitution boxes (S-boxes) using the proposed stochastic models and compare the performance of S-boxes created in this way. Given that the S-box is the core for confusion in Advanced Encryption Standard (AES), the formation of these new S-boxes represents an interesting application of these stochastic models.Article Citation - WoS: 2Citation - Scopus: 4A Study on a Computationally Efficient Controller Design for a Surgical Robotic System(Springernature, 2023) Ayit, Orhan; Dede, Mehmet Ismet CanThe control algorithms of the surgical robotic system using the robot's dynamics produce a relatively high computational load on the processor. This paper develops a computationally efficient computed torque controller by using a simplified dynamic modeling method and implemented in a novel surgical robot experimentally. In addition, an independent joint controller is designed and implemented to compare the results of the computed torque controller.