WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Citation - WoS: 1Citation - Scopus: 1Exploring Sainfoin (Onobrychis Viciifolia) Seed Flour as a Sustainable Plant-Based Food: Germination-Induced Changes in Nutritional Quality, Anti-Nutritional Factors, Phenolic Content, Bioaccessibility, and in Vitro Toxicity(Wiley, 2025) Kaya, Havva Polat; Gungor, Sevde Nur; Tuncel, Nese Yilmaz; Sakarya, Fatma Betul; Andac, Ali Emre; Ozkan, Gulay; Tuncel, Necati BarisBackground and Objectives: Sainfoin is a drought-resistant perennial plant mainly used as animal feed, but its seeds remain underexplored as a food source. This study investigates the effects of germination on the nutritional quality of dehulled sainfoin seeds. Specifically, it examines changes in proximate composition, antinutrients (hydrocyanic acid, tannins, phytates, saponins, and trypsin inhibitors), in vitro starch digestibility, phenolic content, antioxidant capacity, and cytotoxicity. Findings: Germination significantly increased crude protein (up to 45%) and fat (up to 10%) contents. Despite low total starch (similar to 7%), 45-h germination reduced total digestible starch while increasing rapidly digestible starch. Antinutrient levels decreased significantly-tannins by 57%, phytates by 30%, saponins by 40%, and trypsin inhibitors by 29%-with the exception of hydrocyanic acid. Although total phenolics, flavonoids, and antioxidant capacity declined, their bioaccessibility improved. No cytotoxic effects were observed in either raw or germinated seeds. Conclusions: Germination improved the nutritional profile of sainfoin seeds by increasing protein and fat contents, while reducing most antinutrients. Despite a decrease in antioxidant levels, their bioaccessibility was enhanched. The absence of cytotoxic effects further supports the potential application of germinated sainfoin seeds in human nutrition. Significance and Novelty: Although few studies have focused on the green form of sainfoin, which is commonly used as livestock feed, this study reveals that sainfoin seeds offer substantial potential as food, with germination emerging as a simple and effective approach to improving their nutritional properties.Article Investigating the Effects of Functionalized Single Wall Carbon Nanotubes on the Cure Behavior of a Carbon/Epoxy Prepreg System by an Optimized Parameter Approach(Wiley, 2025) Oz, Murat; Uz, Yusuf Can; Tanoglu, Gamze; Tanoglu, Metin; Barisik, MuratCarbon/Epoxy composite materials are used in a wide range of applications due to their superior performance. However, their properties are strongly related to cross-linking reactions occurring during the curing process, and a prior estimation of curing parameters is the key to manufacturing the desired material. This study builds a mathematical model to solve the inverse kinetic problem based on differential scanning calorimetry data and later presents its use in curing experiments. The method derived (Gamze-Murat-Neslisah (GMN) approach) determines the pre-exponential and activation energy of the curing process. Later, an extended experimental study was performed. Functionalized single-wall carbon nanotubes (F-SWCNTs) were prepared by oxidizing their surface with carboxyl to enhance the dispersion of the nanoparticulates. The epoxy resin systems were modified with 0.05%, 0.1%, and 0.2% wt. F-SWCNTs, which were impregnated on carbon fibers (CFs). The curing behavior was studied, cure kinetic parameters were determined, and the thermal behavior was characterized. Differential scanning calorimetry (DSC) data sets for CF/epoxy prepregs containing F-SWCNTs were used for the verification of the proposed method. It was found that the GMN approach is in good agreement with the experimentally measured data for all kinetic parameters. The addition of F-SWCNTs increased the material's curing efficiency as the CNTs enhanced heat transport in composites, reducing the activation energy. The results obtained from the GMN algorithm were also found in good agreement with the well-known Kissinger-Akahira-Sunose (KAS) and Kissinger methods, while the current GMN method revealed itself as an accurate algorithm to obtain the activation energy.Article Citation - WoS: 5Citation - Scopus: 5Magnetically Controllable and Degradable Milliscale Swimmers as Intraocular Drug Implants(Wiley, 2025) Yildiz, E.; Bozuyuk, U.; Yildiz, E.; Wang, F.; Han, M.; Karacakol, A.C.; Sitti, M.Intraocular drug implants are increasingly used for retinal treatments, such as age-related macular degeneration and diabetic macular edema, due to the rapidly aging global population. Although these therapies show promise in arresting disease progression and improving vision, intraocular implant-based therapies can cause unexpected complications that require further surgery due to implant dislocation or uncontrolled drug release. These frequent complications of intraocular drug implants can be overcome using magnetically controllable degradable milliscale swimmers (MDMS) with a double-helix body morphology. A biodegradable hydrogel, polyethylene glycol diacrylate, is employed as the primary 3D printing material of MDMS, and it is magnetized by decorating it with biocompatible polydopamine-encapsulated iron-platinum nanoparticles. MDMS have comparable dimensions to commercial intraocular implants that achieve translational motions in both aqueous and vitreous bodies. They can be imaged in real-time using optical coherence tomography, ultrasound, and photoacoustic imaging. Thanks to their biodegradable hydrogel-based structure, they can be loaded with anti-inflammatory drug molecules and release the medications without disrupting retinal epithelial viability and barrier function, and decrease proinflammatory cytokine release significantly. These magnetically controllable swimmers, which degrade in a couple of months, can be used for less invasive and more precise intraocular drug delivery compared to commercial intraocular drug implants. © 2025 The Author(s). Advanced Science published by Wiley-VCH GmbH.Article Citation - WoS: 3Citation - Scopus: 3Performance Improvement of Carbon Fiber-Reinforced Abs Composites by Introducing Fullerene Nanoparticles(Wiley, 2025) Akar, Alinda Oyku; Yildiz, Umit Hakan; Tirkes, Seha; Tayfun, Umit; Hacivelioglu, FerdaRecently, polymer composites have been extensively researched in industrial fields such as electrical conductance, ohmic heating, electromagnetic shielding and electrostatic discharge, particularly in engineering polymers reinforced with carbonaceous additions. Herein, fullerene (C60) and short carbon fiber (CF) were incorporated with acrylonitrile-butadiene-styrene copolymer (ABS) using melt-compounding followed by an injection-molding process. Composite samples were produced with contents of 20 wt% of CF besides 0.1, 0.5 and 1.0 wt% of C60. Tensile, impact, hardness and wear tests, conductive atomic force microscopy, dynamic mechanical analysis, thermogravimetric analysis, melt flow index tests and scanning electron microscopy (SEM) were performed to characterize mechanical, electrical, thermomechanical, thermal, melt-flow and structural behaviors of ABS-based composites involving CF and C60. Based on the mechanical test findings obtained for the developed composites, comprising tensile and impact test results, C60 additions contributed to a significant rise in tensile strength and impact resistance of CF-reinforced ABS composites, with a 20% increase in tensile resistance being achieved by introduction C60 into the ABS/CF structure. C60 addition enhanced efficiency by 50% in terms of tensile modulus. Electrical conductivity measurements confirmed that C60 nanoparticles and CF exhibited a synergy. The optimum synergistic ratio of C60/CF was obtained as 0.5/20. The conductive path in the ABS/CF composite system was established by incorporating C60 with different loading amounts. SEM micrographs of composites demonstrated that C60 nanoparticles were dispersed homogeneously into the ABS matrix involving lower amounts of C60. (c) 2025 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.Article Citation - WoS: 2Citation - Scopus: 2New Copper and Cobalt Complexes Based on a Fluorinated Pyrazole Derivative, Synthesis, Characterization and Antibacterial Activity(Wiley, 2025) Amin, Mina A.; Diker, Halide; Sahin, Onur; Varlikli, Canan; Soliman, Ahmed A.Two copper and cobalt complexes based on 3-(trifluoromethyl)-4-((3-(trifluoromethyl)phenyl)diazenyl)-1H-pyrazol-5-ol (Httdp) have been prepared and characterized using different physicochemical techniques. The crystal structure of the copper complex has been proven to be a square pyramidal, and the cobalt complex has an octahedral structure. DFT calculations of the complexes were performed, and the energy gaps between the HOMO-LUMO of the complexes (-3.38676 to -3.18138 eV) and the Cu (II) complex reflect a higher relative stability compared with Httdp and the Co (II) complex. The antibacterial activities of the two complexes were evaluated. The Co (II) complex demonstrated the highest antibacterial activity against various bacteria compared with Httdp and the Cu (II) complex. The mean inhibition zones exhibited by the Co (II) complex showed the highest activities toward the Gram-negative bacterial strains with mean inhibition zones of 30.3 +/- 0.6 (Staphylococcus aureus) and 25.7 +/- 0.6 (Bacillus subtilis) mm. Docking studies were carried out using S. aureus tyrosyl-tRNA synthetase (PDB ID: 1JIJ) to assess the antimicrobial activities, proving that the complexes were efficient for the protein.Article Regression Analysis of Material Properties and Hardness of Dense Boron Carbide(Wiley, 2025) Toksoy, M. Fatih; Haber, Richard A.Material properties directly affect the final performance of the produced articles. This study aims to establish a correlation between materials properties and hardness of boron carbide samples. Ten different boron carbide powders were sintered to high densities by spark plasma sintering, and material properties (grain size, density, stoichiometry, and free carbon) were analyzed. Hardness tests were conducted on these samples. All experimental procedures were completed by a single operator, and the same instruments were used for all the samples. Multiple linear regressions using the ordinary least squares method in SPSS were carried out to identify the relationship between hardness and material properties. Analyses showed density is the most dominant property, surpassing any other parameter. Grain size became more dominant at higher densities (>99%) and affected hardness results. Both grain size and density are the result of the starting powder and the densification procedure. This study showed that 80% of the hardness variation can be explained by this model.Conference Object Investigation of the role of Wnt/β-catenin signaling in development of Alzheimer's disease in a zebrafish model of mmyloid-β toxicity(Wiley, 2024) Nazlı, Dilek; Ipekgil, D.; Poyraz, Y. K.; Catak, B.; Sahin, E. Turhanlar; Özhan, GüneşThe Wnt/β-catenin signaling pathway, an evolutionarily conserved and pivotal pathway associated with synapse formation in adulthood, plays a crucial role in Alzheimer's disease (AD). AD, marked by various pathologies, is primarily linked to the accumulation of extracellular beta-amyloid plaques. The interplay between this accumulation and disruptions in the Wnt/β-catenin signaling pathway triggers synaptic degeneration, resulting in synaptic dysfunction and AD progression. In this study, we modeled AD induced by the Aβ42 peptide using adult transgenic (6XTCF) zebrafish. To establish the zebrafish AD model, we employed cerebroventricular microinjection (CVMI) with the Aβ42 peptide. Fish, anesthetized prior to CVMI, were positioned on a stable platform, and the Aβ42 peptide was injected into the telencephalon region of the brain by a capillary needle. Brain samples were collected on 1, 3, 4, 7, and 14 days post-CVMI (dpi) to analyze changes in Aβ42 peptide accumulation, the immune system response, synaptic degeneration, apoptosis, and the expression of genes related to proliferation using qPCR and immunofluorescent staining. To examine the role of the Wnt/β-catenin signaling pathway in the molecular mechanism of AD development, fish exhibiting high levels of regeneration on days 7 and 14 were treated with the IWR-1 drug, which inhibits the Wnt/β-catenin signaling by stabilizing the Axin2 protein, thereby suppressing the regenerative response. Our results revealed that the AD model manifested on 3dpi, with the regenerative response reaching its peak on 7dpi and 14dpi. Treatment with IWR-1 resulted in increased Aβ42 accumulation, accelerated synaptic degeneration, and elevated cell deaths in fish where the Wnt signaling pathway was inhibited. In conclusion, our adult zebrafish AD model is poised to elucidate the molecular mechanisms connecting the Wnt signaling pathway and AD, thereby contributing to the development of alternative therapeutic approaches for AD patients.Article Citation - WoS: 1Citation - Scopus: 1Hn1 Functions in Protein Synthesis Regulation Via Mtor-Rps6 Axis and Maintains Nucleolar Integrity(Wiley, 2025) Ozduman, Guelseren; Javed, Aadil; Alasar, Azime Akcaoz; Akgul, Buenyamin; Korkmaz, Kemal SamiHaematological and Neurological Expressed 1 (HN1) is an oncogene for various cancers and previously has been linked with centrosome clustering and cell cycle pathways. Moreover, HN1 has recently been reported to activate mTOR signalling, which is the regulator of ribosome biogenesis and maintenance. We explored the role of HN1 in mTOR signalling through various gain- and loss-of-function experiments using biochemical approaches in different cell lines. We demonstrated for the first time that HN1 is required for nucleolar organiser region (NOR) integrity and function. Immunoprecipitation-based association and colocalization studies demonstrated that HN1 is an important component of the mTOR-RPS6 axis, and its depletion results with reduced mRNA translation in mammalian cancer cell lines. This study also demonstrated that the depletion of HN1 leads to the irregular distribution of nucleolar structures, potentially leading to cell cycle deregulation as reported previously. Accordingly, components of the translation machinery aggregate with a distinct speckled pattern, lose their essential interactions and ultimately impair mRNA translation efficiency when the HN1 is depleted. These results suggest that HN1 is an essential component of the nucleolus, required for ribosome biogenesis as well as global mRNA translation.Article Secrecy performance of full-duplex space-air integrated networks in the presence of active/passive eavesdropper, and friendly jammer(Wiley, 2024) Buyuksar, Ayse Betul; Erdoğan, Eylem; Altunbas, IbrahimIn this paper, a full-duplex (FD) space-air ground integrated network (SAGIN) system with passive and active eavesdroppers (PE/AE) and a friendly jammer (FJ) is investigated. The shadowing side information (SSI)-based unmanned aerial vehicle relay node (URN) selection strategy is considered to improve signal-to-interference plus noise power ratio (SINR) at the ground destination unit. To quantify the secrecy performance of the considered scenario, outage probability (OP), interception probability (IP), and transmission secrecy outage probability (TSOP) are investigated in the presence of FJ and PE/AE. The results have shown that aerial AE is an important threat since it can severely degrade the OP of the main transmission link. Furthermore, the FJ can decrease the IP of the eavesdropper by causing interference with the cost of power consumption of URNs. Simulations are performed to verify the theoretical findings.Article Citation - WoS: 1Citation - Scopus: 1Application of a Size Measurement Standard for Data Warehouse Projects(Wiley, 2024) Unlu, Hueseyin; Yueruem, Ozan Rasit; Yildiz, Ali; Demirors, OnurMethodologyIn this research, we conducted a case study to establish a foundation for size measurement and effort estimation in DWH projects. We first applied a productivity-based estimation approach using linear regression with the ISBSG repository to assist organizations without historical data. We then evaluated various machine learning algorithms to improve estimation accuracy. Finally, we tested a combined model that integrates both approaches for estimating effort in external projects.ResultsUsing the ISBSG dataset, linear regression models based on productivity achieved a Mean Magnitude of Relative Error (MMRE) of 0.285. Machine learning algorithms improved accuracy by 22.81%, reducing the MMRE to 0.220. The final model, applied to external projects, yielded MRE values between 0.010 and 0.245.ConclusionThe ISBSG repository is a valuable resource for effort estimation in DWH projects. Combining productivity-based estimation with machine learning enhances accuracy and predictive performance, making it a more reliable approach than traditional models.