Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Reflection on Designing: Metacognitive Interventions to Enhance Metacognitive Awareness, Motivation, and Performance in Design Learning(Springer, 2025) Yazici, Gizem; Dogan, FehmiDesign education involves ill-defined problem-solving that demands both creativity and self-regulation. While metacognitive awareness significantly enhances learning outcomes and motivation, there is limited empirical evidence on how to systematically foster this skill in design studios. This study aims to investigate whether metacognitive interventions increase architecture students' metacognitive awareness levels, academic goal orientations, and design course success. In a quasi-experimental design, 84 third-year architecture students were divided into experimental (n = 58) and control (n = 26) groups. Pre-post-test data were collected using the MAI and AGOQ scales. Three structured interventions were implemented in the experimental group over six weeks. In the students who received the interventions, significant increases were observed in metacognitive awareness, mastery-performance goal orientation, and design course grades. In students with high awareness, mastery orientation, metacognitive awareness, and design course grades increased significantly, while in students with low awareness, metacognitive awareness and performance orientation increased. Pretest MAI and AGOQ scores accounted for 72.8% of the variance in grades, with MAI showing the strongest positive influence. Learning and proving orientations were moderately and positively correlated to grades, while avoidance orientation showed a moderate negative correlation. Metacognitive interventions enhance learning outcomes in design education by supporting metacognition and motivation.Article A Comprehensive Database and a New Model for the Axial Response of Heat-Damaged Concrete Before and After FRP Confinement(Springer, 2025) Akdag, Nefise; Demir, UgurIn this study, a total of 330 concrete specimens, compiled from existing experimental data, are systematically reviewed to assess their post-fire axial stress-strain behavior before and after circumferential confinement with fiber-reinforced polymers (FRPs). The selection criteria for the database are as follows: (i) studies had to be published in English, (ii) both lateral and axial ultimate strains must have been measured, (iii) the use of additional strengthening materials in combination with FRPs was excluded, (iv) only plain concrete specimens were considered, and (v) specimen dimensions and instrumentation details had to be explicitly reported. The dataset is structured to include heating/cooling and curing conditions, specimen properties, and FRP characteristics. Subsequently, the predictive accuracy of available models for post-fire axial strength and ultimate strain of concrete members, both before and after FRP confinement, is evaluated. The results based on the reviewed comprehensive database indicate that these models are inadequate in capturing the observed behavior in the experiments. As such, a new analytical model is developed based on the compiled dataset. The proposed model demonstrated reliable predictive performance in terms of post-fire axial response of concrete before and after FRP confinement while remaining user-friendly for practical engineering applications. This is done such that universal design guidelines on the behavior of heat-damaged concrete strengthened by FRP composites can be reliably formulated.Article Citation - WoS: 2Citation - Scopus: 1Isolation, Purification, Structural Characterization, and Encapsulation of Sulforaphane From Cabbage Seeds Using the Ionic Gelation Method(Springer, 2025) Oner, Beste; Aydin, Ozgun Koprualan; Okkali, Gaye Sumer; Sarikahya, Nazli Boke; Nadeem, Hilal Sahin; KaymakErtekin, FigenSulforaphane (SFN), a phytochemical with anticancer and antibacterial properties, is a secondary metabolite found in cabbage (both in the plants and seeds), a member of the Brassica (crusifer) family. However, pure sulforaphane is volatile, sensitive to pH, temperature, light, and oxygen, and is also only oil-soluble, limiting its stability and bioaccessibility. Therefore, encapsulation is required to enhance stability and control its release. In this study, sulforaphane-rich extracts were first obtained from cabbage seeds using a hybrid ultrasonic-microwave extraction method yielding 24.35%, with a sulforaphane content of 8202.68 mu g/g DM, followed by purification of sulforaphane through chromatography. Structural elucidation was performed using H-1-NMR, C-13-NMR, and QTOF LC/MS. The pure SFN (> 90% purity) was encapsulated using the ionic gelation method to improve its bioaccessibility and stability. Various coating material combinations, sodium alginate/chitosan and sodium alginate/pectin were evaluated for the encapsulation process. Fourier-transform infrared spectroscopy (FTIR) was used to investigate the relationship between the coating materials, and the most efficient combination was selected. Optimization of process variables using central composite rotatable design (CCRD) identified the optimal conditions: 1.41% sulforaphane-oil mixture, 0.18% chitosan, and 6.88 min waiting time. Under these conditions, microcapsules were produced with high encapsulation efficiency (76.02%) and low solubility (4.78%). & Idot;n vitro bioaccessibility studies further confirmed minimal sulforaphane release during the oral and gastric phases, with a low release in the intestinal phase. These results demonstrate the effectiveness of the encapsulation system in protecting sulforaphane under harsh gastrointestinal conditions.Article Task-Specific Dynamical Entropy Variations in EEG as a Biomarker for Parkinson's Disease Progression(Springer, 2025) Onay, Fatih; Karacali, BilgeUncovering the neuronal mechanisms un-derlying optimal behavioral performance is essential to understand how the brain dynamically adapts to changing conditions. In Parkinson's disease (PD), these neuronal mechanisms are disrupted and lead to impairments in motor coordination and higher-order cognitive functions. This study investigates neuronal dynamics during a lower-limb pedaling task by analyzing the dynamical entropy of EEG signals in healthy controls (HC), PD patients, and PD patients with freezing of gait (PDFOG). We examined both average entropy changes and entropy variability across trials to characterize task-specific neural adaptations across disease progression. Results showed that PD and PDFOG patients exhibited decreased levels of permutation entropy in frontal and parietal regions, which may be associated with loss of cognitive adapta-tion due to altered information processing. Additionally, Vasicek's entropy variability in both PD groups was significantly diminished in occipital and left frontal regions, suggesting reduced cognitive capacity to dy-namically allocate neuronal resources during task engagement. We extended this analysis to the classification of groups using LDA and SVM classifiers, where entropy-derived features achieved a classification accuracy of up to 96.15% when distinguishing HC from PDFOG patients. This dynamical entropic framework provides a novel approach for capturing neural complexity changes during task performance, revealing subtle cognitive-motor impairments in PD. Understanding the maintenance of cognitive information processing and flexibility in response to motor and cognitive task demands could be a useful tool to track PD diagnosis and progression in addition to resting-state analyses.Article Citation - WoS: 1Citation - Scopus: 1Fabrication of Electrospun Polycaprolactone Nanofibrous Mats Loaded With Purple Basil Extract (Ocimum Basilicum L.) as Colorimetric Ph Indicator Films(Springer, 2025) Erez, Elif; Eroglu, Ahmet Emin; Bayramoglu, BesteIntelligent packaging with colorimetric pH indicators revolutionizes traditional food packaging by enabling real-time food quality monitoring. This study used electrospinning to develop pH indicator films from polycaprolactone (PCL) incorporating purple basil extract (PBE). Nanofibrous films containing 0.2% PBE (PCLN_0.2PBE), 0.4% PBE (PCLN_0.4PBE), and 0.6% PBE (PCLN_0.6PBE) were fabricated using different electrospinning conditions. The PCLNs fabricated with a voltage of 20 kV and a flow rate of 1.6 mL/h exhibited the most uniform and bead-free morphology according to scanning electron microscopy. The chemical, thermal, mechanical, and wetting characterization of the films was performed by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermal gravimetric analysis, texture analysis, and contact angle analysis, respectively. Both PCLN_0.4PBE and PCLN_0.6PBE films displayed fast (4-5 s) and clear color transitions (Delta E > 3.5) to successive pH buffers within the range critical for food deterioration, while they exhibited excellent color changes (Delta E > 5) for pH variations of at least two units. The PCLN_0.6 PBE film displayed a Delta E of similar to 5 in only 5 min of exposure to ammonia vapor, whereas PCLN_0.4PBE showed a similar color change for over 15 min. The interaction between the films and acidic and alkaline semi-solid foods was simulated using gelatin gels at pH 2.5 and 11, respectively. Both films displayed significant color transitions (Delta E > similar to 9) within 15 min of contact with the gels, with the response from PCLN_0.6 PBE being more pronounced. The color stability in both films was maintained for up to 14 days at 4 degrees C, offering potential early warnings against food spoilage. PBE release was evaluated against different food simulants. The highest release occurred in 50% ethanol; the films demonstrated resistance to 3% acetic acid. The findings indicate that electrospun PCL films integrated with PBE have a promising potential to serve as colorimetric pH indicators for monitoring the freshness of food products.Article Citation - WoS: 3Citation - Scopus: 2Cradle-To Life Cycle Assessment of Heavy Machinery Manufacturing: a Case Study in Türkiye(Springer, 2025) Üçtuğ, F.G.; Ediger, V.Ş.; Küçüker, M.A.; Berk, İ.; İnan, A.; Moghadasi Fereidani, B.Purpose: Amidst accelerated industrialization and urbanization, the surge in heavy equipment production, crucial for construction, mining, industry, and transportation, necessitates a comprehensive examination of its environmental implications from a sustainability standpoint. This study aims to scrutinize the environmental impacts of manufacturing forklifts and semi-trailers in Türkiye, employing the life cycle assessment (LCA) methodology. Methods: The life cycle assessment (LCA) methodology is the foundational framework for evaluating the environmental impacts associated with forklift and semi-trailer manufacturing. A cradle-to-gate approach was employed. CCaLC2 software alongside the Ecoinvent 3.0 database and CML LCIA methodology was used. Results: The carbon footprint analysis reveals that the production of a single forklift and semi-trailer generates 10.8 tons CO2eq. and 24.9 tons CO2eq. of emissions, respectively. Considering the mass of the machinery, these figures translate to 2.8 ton CO2eq./ton machinery and 1.57 ton CO2eq/ton machinery for the forklift and semi-trailer, respectively. These results were found to be consistent with values reported for similar (but not identical) heavy machinery. Notably, the predominant share of environmental impact stems from raw material acquisition for both products, with subsequent contributions from various production stages. Steel utilization emerges as the primary contributor to all environmental impact categories, constituting an average contribution of 75%. Noteworthy exceptions include the acidification potential of forklift production, where the incorporation of the engine emerges as the primary hotspot with a significant 38% contribution. Conclusions: The findings present the environmental footprint associated with forklift and semi-trailer manufacturing, emphasizing the pivotal role of raw material acquisition, particularly steel utilization. Insights derived from this environmental impact assessment provide invaluable guidance for enhancing environmental sustainability. Decision-makers and industry stakeholders can leverage these conclusions to implement targeted measures, such as exploring alternative materials or refining production processes, to mitigate the environmental consequences of resource-intensive heavy equipment manufacturing, aligning with broader sustainability objectives. © The Author(s) 2025.Article Citation - WoS: 3Citation - Scopus: 3Hybrid Silica Aerogels From Bridged Silicon Alkoxides: Ultralow Thermal Conductivity for Low-Temperature Applications(Springer, 2025) Abebe, A. M.; Biesuz, M.; Vakifahmetoglu, C.; Cassetta, M.; Soraru, G. D.Hybrid silica aerogels are promising materials for thermal insulation applications. Highly porous aerogels were synthesized from bridged bis(triethoxysilyl)methane BTEM and triethoxysilane TREOS silicon alkoxides via the sol-gel process. The carbon content in the hybrid aerogels decreased with increasing amounts of TREOS. Crack-free monolith aerogels were synthesized through supercritical drying, which is crucial for thermal and optical investigations. The aerogels are characterized by high BET surface areas ranging from 700 to 1400 m(2)/g, pore volumes between 2.0 and 10.5 cm(3)/g, and a maximum porosity of 95%. The thermal conductivity of the aerogels at room temperature was measured via a hot disk apparatus. The materials exhibited ultralow thermal conductivity, reaching a minimum value of 15 mW/mK. This value ranks among the lowest reported values for silica-based aerogels in the literature. Optical transmittance measurements indicated high transparency, exceeding 80% in the visible region. Therefore, these exceptional properties of low density, high optical transparency, and low thermal conductivity make these materials promising candidates for transparent insulation applications.Review Citation - Scopus: 5A Comparative Evaluation of Dark Fermentative Bioreactor Configurations for Enhanced Hydrogen Production(Springer, 2025) Gören, Ayşegül Yağmur; Dincer, I.; Khalvati, A.Energy from renewable resources has been growing in popularity, which ultimately helps reduce emissions of greenhouse gases (GHGs) and contaminants. Since hydrogen (H2) has a higher combustion production of energy than hydrocarbon fuels, it has been identified as a clean, sustainable, and environmentally friendly energy source. There are several benefits to producing biohydrogen (bioH2) from renewable sources, including lower cost and increased sustainability. Among the bioH2 production processes, dark fermentation supports commercialization and scale-up for industrial applications. This paper considers the various bioreactors, such as anaerobic sequencing batch, continuous stirred, up-flow, fixed-bed, and membrane reactors, and their operational approaches for bioH2 production. This review paper also performs the bibliometric analysis method to identify historical and current developments in a particular field of reactor configuration studies. Furthermore, the main variables influencing reactor performance and methods for increasing process efficiency considering economic and environmental aspects are addressed. The results revealed that continuously stirred reactors are widely utilized for bioH2 production as a cost-effective reactor configuration. Moreover, the membrane bioreactors and fixed-bed reactors are yielded higher bioH2 performance than other configurations. Nevertheless, high energy consumption and costs have presented the need for further development of reactors. Consequently, future recommendations to solve the critical problems faced in reactor configurations, the gaps in the literature, and the points that need improvement were comprehensively reported. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.Article Citation - WoS: 7Citation - Scopus: 7Bond-Based Peridynamic Fatigue Analysis of Ductile Materials With Neuber's Plasticity Correction(Springer, 2024) Altay, Ugur; Dorduncu, Mehmet; Kadioglu, Suat; Madenci, ErdoganThis study introduces an approach for performing bond-based (BB) peridynamic (PD) fatigue analysis of ductile materials. Existing BB PD fatigue models do not account for the effect of plastic deformation. The current approach addresses this by incorporating Neuber's plasticity correction concept into the fatigue model. Neuber's correction adjusts the stress and strain predictions of the PD elastic solution to account for local plastic deformation around crack tips. The PD fatigue simulations demonstrate the effectiveness of this method and improvements in fatigue life predictions by considering local plasticity effects. The numerical results first examine the response of a ductile plate without a crack under quasi-static monotonic loading. Subsequently, specimens exhibiting Mode I and mixed-mode crack propagation paths due to cyclic loading are analyzed. The PD predictions accurately capture the test data. Additionally, the model specifically investigates the effect of a stop hole on fatigue life.Article Citation - WoS: 1Citation - Scopus: 1Studies on the Probiotic, Adhesion, and Induction Properties of Artisanal Lactic Acid Bacteria: To Customize a Gastrointestinal Niche To Trigger Anti-Obesity Functions(Springer, 2024) Kamber, A.; Albayrak, C. Bulut; Harsa, H. S.The primary goals of this work are to explore the potential of probiotic lactic acid bacteria's (LAB) mucin/mucus layer thickening properties and to identify anti-obesity candidate strains that improve appropriate habitat for use with the Akkermansia group population in the future. The HT-29 cell binding, antimicrobial properties, adhesion to the mucin/mucus layer, growth in the presence of mucin, stability during in vitro gastrointestinal (GI) conditions, biofilm formation, and mucin/mucus thickness increment abilities were all assessed for artisanal LAB strains. Sixteen LAB strains out of 40 were chosen for further analysis based on their ability to withstand GI conditions. Thirteen strains remained viable in simulated intestinal fluid, while most showed high viability in gastric juice simulation. Furthermore, 35.9-65.4% of those 16 bacteria adhered to the mucin layer. Besides, different lactate levels were produced, and Streptococcus thermophilus UIN9 exhibited the highest biofilm development. In the HT-29 cell culture, the highest mucin levels were 333.87 mu g/mL with O. AK8 at 50 mM lactate, 313.38 mu g/mL with Lactobacillus acidophilus NRRL-B 1910 with initial mucin, and 311.41 mu g/mL with Lacticaseibacillus casei NRRL-B 441 with initial mucin and 50 mM lactate. Nine LAB strains have been proposed as anti-obesity candidates, with olive isolates of Lactiplantibacillus plantarum being particularly important due to their ability to avoid mucin sugar consumption. Probiotic LAB's attachment to the colonic mucosa and its ability to stimulate HT-29 cells to secrete mucus are critical mechanisms that may support the development of Akkermansia.