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- MakaleAçık Erişim2025Scopus SJRQ1ADAMTS-1, a multifunctional proteinase, in the uterus of both estrous cycle rats and ovariectomized rats can be regulated via hormones
Parlak Ak, Tuba; Yaman, Mine; Bayrakdar, Ali; Bulmus, Ozgur
Remodeling of the extracellular matrix (ECM) throughout the estrous cycle is one of the most striking features of the uterus. A disintegrin and metalloprotease with thrombospondin type I motifs (ADAMTS-1) is a metalloproteinase responsible for the degradation of some proteoglycans, which are ECM components. In this study, ADAMTS-1 distribution was analyzed in the uterus of ovariectomized rats administered 17β-estradiol (E2) and progesterone (P4) and in the uterus at different estrous stages. Ovariectomized (OVX) rats were subjected to single and combined E2 (0.2 mg/kg) and P4 (10 mg/kg) hormone replacement therapies. E2 was administered for 3 consecutive days, followed by E2, P4, or E2 + P4 for 4 consecutive days. The serum level of E2 decreased from the proestrus phase to the diestrus phase, but that of P4 was the highest in the estrus phase. During the estrus phase, the serum level of luteinizing hormone (LH) was the lowest and that of follicle-stimulating hormone (FSH) was the highest. P4 level increased significantly in the OVX + P4 and OVX + E2 + P4 groups compared with the OVX group. The serum levels of LH and FSH decreased in the OVX + E2 and OVX + P4 groups compared with the OVX group, and were the lowest in the OVX + E2 + P4 group. ADAMTS-1 immunoreactivity in luminal, glandular, and stromal cells of the uterus decreased from proestrus to diestrus. When immunoreactivity in hormone replacement groups was compared, weak immunoreactivity was observed in the OVX group. ADAMTS-1 immunoreactivity gradually increased in OVX + P4 and OVX + E2 groups, and was particularly notable in luminal, glandular, and stromal cells in the OVX + E2 + P4 group. ADAMTS-1 distribution was affected by the estrous cycle process and hormone replacement therapy in the OVX procedure.
AtıfScopus1OpenAlex1
İncele - MakaleYalnız künye2026Scopus SJRQ3Diverse optical soliton solutions to the generalized resonant nonlinear Schrödinger equation through an integral method
Atas, Sibel Sehriban; Ali, Karmina K.
This paper is concerned with the generalized resonant nonlinear Schrödinger equation with an arbitrary index, which describes ultra-short pulse propagation in optical fibers. The study uses the main integration method: the modified generalized Riccati equation mapping method, to construct and analyze combined forms of optical soliton solutions. The results are multifaceted, revealing a variety of optical soliton solutions, such as rational solutions in hyperbolic functions, combined solutions of hyperbolic and trigonometric functions, bright, singular, , kink-shaped, smooth kink, and periodic singular. Moreover, two-dimensional, three-dimensional, and contour graphs of some obtained optical soliton solutions are plotted to illustrate the importance of the generalized resonant nonlinear Schrödinger equation, using suitable values of physical parameters. Two-dimensional graphs are used to illustrate the dynamic behavior of the solutions, taking into account the impact of the nonlinear index n and the time parameter t. The obtained optical solutions are considered novel and most likely have not been reported in the literature before.
AtıfScopus1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ1Comparative assessment of individual rare-earth oxides and high-entropy rare-earth oxides reinforcements on the structural, physical, and radiation transmission properties of Inconel 718
Gül, Ali Oktay; Gökhan Albayrak, M.; Güler, Ömer; Özkul, İskender; Baykal, Duygu Sen; Almisned, Ghada; Tekin, H.O.
This study addresses a fundamental materials design question for radiation-resistant superalloys: whether rare-earth (RE) oxides are more effective when incorporated individually or when introduced collectively in a high-entropy rare-earth oxide (HE-RE2O3) form. In this context, Inconel 718 (IN718) composites were reinforced with single RE2O3 phases such as Sm2O3, Tm2O3, Er2O3, Yb2O3, Eu2O3, and La2O3 at 10 wt% and with a mechanically alloyed HE-RE2O3 phase at 1-20 wt%. Structural analyses confirmed the formation of a single-phase HE-RE2O3 with a cubic bixbyite structure and its stable integration into the IN718 matrix. Gamma-ray shielding properties were systematically evaluated over a wide photon energy range. The HE-RE2O3 reinforced samples, particularly at higher loadings, exhibited consistently higher mass and linear attenuation coefficients, elevated effective atomic numbers, reduced half-value layers, and lower buildup factors compared to both the base alloy and single-oxide reinforced counterparts, demonstrating a clear collective attenuation effect. Fast neutron removal cross sections showed more moderate variations, reflecting the dominance of neutron scattering and mass-dependent interaction mechanisms rather than atomic number effects. It can be concluded that incorporating RE elements through a high-entropy oxide configuration provides a more effective and collective compositional contribution for enhancing the radiation shielding performance of IN718 than adding RE oxides individually, offering a promising pathway for advanced nuclear and radiation-relevant applications.
AtıfScopus1OpenAlex1İncele - MakaleYalnız künye2026Scopus SJRQ1Enhancement of chlorogenic acid application on the quality, biochemical properties, and cold storage stability of sweet cherry fruit
Gundogdu, Muttalip; Sen, Fatih; Aglar, Erdal; Kılıncer, Mustafa
This study investigated the effects of chlorogenic acid (ChlA) applications on postharvest quality characteristics and biochemical components of sweet cherry (Prunus avium L. cv. ‘0900 Ziraat’) fruit. Fruits were treated with control, 0.5, 1.0, and 1.5 mM ChlA and stored at 4 ± 0.5 °C for 21 days. Storage significantly increased weight loss and decay rate while reducing respiration rate and biochemical quality. At the end of storage, the 1.5 mM ChlA treatment reduced weight loss from 8.32% in the control to 5.20% and decreased decay rate from 9.16% to 4.50%. ChlA applications also slowed changes in soluble solids content (SSC), titratable acidity (TA), and pH, contributing to a more stable chemical composition. The highest vitamin C content at the end of storage was recorded in the 1.5 mM ChlA treatment (11.71 mg 100 g⁻¹), compared with 9.97 mg 100 g⁻¹ in the control. Similarly, chlorogenic acid significantly delayed losses of organic acids and phenolic compounds; for example, quercetin content was maintained at 6.80 mg 100 g⁻¹ in 1.5 mM ChlA-treated fruit compared with 3.78 mg 100 g⁻¹ in the control after 21 days of storage. Principal component analysis (PCA) and correlation analysis revealed strong relationships among quality attributes and biochemical compounds and demonstrated the positive role of ChlA in preserving overall fruit quality. Overall, chlorogenic acid, particularly at 1.5 mM, effectively reduced postharvest quality losses and enhanced biochemical stability during cold storage.
- MakaleAçık Erişim2026Scopus SJRQ1Quantifying agricultural resilience under climate variability: a data-driven climate resilience index for European cereal systems
Utku, Anil; Radulescu, Magdalena; Barut, Abdulkadir; Alofaysan, Hind
Climate variability and extreme weather events pose an increasingly serious threat to agricultural productivity in Europe. Although many studies have focused on the mean yield response to climate change, relatively few have attempted to offer a comprehensive, multi-dimensional view of agricultural resilience, separating long-term productivity trends from short-term climate-induced fluctuations. In this paper, a data-driven Climate Resilience Index is proposed to assess the resilience of European cereal systems under climate stress. Annual yield time series are decomposed into trend and anomaly components to identify interannual deviations driven by climate variability. Machine learning and deep learning algorithms, including RF, CatBoost, CNN, LSTM, TCN, and a TCN-LSTM hybrid model, are used to assess the predictive validity of climate extreme indices and persistence patterns. Among the evaluated models, the TCN-LSTM architecture achieved the highest predictive performance with 0.8347 R2, outperforming standalone temporal and ensemble-based models. The PCA-based exposure framework explained 68.4% of the total climate variability within the first principal component, indicating a highly concentrated climate-stress structure. Feature importance analyses further revealed that lagged yield anomalies and rolling volatility indicators were the dominant predictors of resilience dynamics. The findings show that temporal models perform better than traditional ensemble methods, emphasizing the significance of multi-year recovery mechanisms in anomaly evolution. To provide a consistent measure of exposure, principal component analysis is used to reduce correlated climate indicators into a multi-dimensional climate stress index. The CRI captures these three essential elements: climate exposure, yield variability, and recovery. The results at the country level show substantial variability across Europe, indicating that while exposure intensity is important, recovery dynamics are also critical to understanding resilience. The results also show that there are structurally distinct resilience profiles, and robustness tests indicate that country rankings are not sensitive to different weights and recovery functions. The results clearly show that recovery and adaptive capacity are critical to agricultural sustainability amid growing climate uncertainty. The CRI developed in this paper provides a clear, empirically valid framework for comparing resilience in agricultural systems.
AtıfScopus1OpenAlex2İncele - MakaleYalnız künye2027Scopus SJRQ2Design, structural characterization, and simulated radiation-transport assessment of high-entropy (GdErSmEuYb)2X2O7 (X = Hf, Zr, Ce, Si) rare-earth oxides
Güler, Ömer; Güler, Seval Hale; Yayla, Nihal; Baykal, Duygu Sen; Durmus, Hasan; Tekin, Huseyin Ozan; ALMisned, Ghada
This study investigates the structural, microstructural, surface-chemical, and radiation attenuation behaviour of high-entropy rare-earth oxide (HEO) powder compositions synthesized as TBC-related candidate coating materials, whose radiation attenuation potential was assessed within a computational Inconel-718-based sandwich model. Four compositions, namely (GdErSmEuYb)2Hf2O7, (GdErSmEuYb)2Ce2O7, (GdErSmEuYb)2Zr2O7, and (GdErSmEuYb)2Si2O7, were synthesized via high-energy ball milling followed by calcination at 1200 °C. X-ray diffraction results revealed the formation of distinct crystal structures depending on B-site chemistry, including defective fluorite and silicate-type phases. SEM-EDS mapping confirmed homogeneous elemental distribution, while XPS analysis demonstrated mixed valence states and different oxygen vacancy concentrations across the compositions. To evaluate radiation attenuation performance, a sandwich-type geometry consisting of a 10 mm Inconel-718 core with symmetrically defined simulated HEO layers was modelled using Monte Carlo simulations. Gamma-ray transmission was analyzed over an energy range of 0.276-1.332 MeV, and fast neutron attenuation was assessed at 4.5 MeV. The results showed that transmission factors decreased with increasing coating thickness, with the effect being more pronounced at lower photon energies. Among the investigated compositions, the Hf-based system exhibited the most favorable predicted attenuation response for both gamma rays and fast neutrons under the defined simulation conditions. Theoretical half-value layer calculations also showed good agreement with the simulation results. Overall, the findings indicate that high-entropy rare-earth oxide coatings may provide an additional radiation attenuation contribution when incorporated as layers in Inconel-718-based systems. However, since direct thermal-barrier properties such as thermal conductivity, thermal diffusivity, thermal cycling resistance, and thermal-stress behavior were not evaluated in the present work, the present study should be interpreted as a structural and radiation-transport assessment of TBC-related coating candidates rather than a direct demonstration of thermal-barrier performance.
- MakaleAçık Erişim2026Scopus SJRQ2Designing a novel FeCoNiMnCu high-entropy Alloy: Synthesis, structural evolution, magnetic behavior, and radiation shielding performance
Güler, Ömer; Şimşek, Telem; Şimşek, Tuncay; Evin, Ertan; Baykal, Duygu Sen; ALMisned, Ghada; Tekin, H.O.
In this study, a novel FeCoNiMnCu HEA was synthesized via mechanical alloying and exhibited a single-phase face-centered cubic (FCC) structure with a crystallite size of 11.7 nm and a lattice strain of 0.81 %. Magnetic characterization revealed soft ferromagnetic behavior with a saturation magnetization of 32 emu/g at 300 K, increasing to 53 emu/g at 10 K. The alloy demonstrated excellent gamma-ray attenuation, with lower half-value layer (HVL) and mean free path (MFP) values than conventional shielding materials. Notably, its fast neutron removal cross-section (ΣR = 0.1654 cm−1) outperformed standard materials such as B4C, graphite, and water in the fast neutron energy range. These findings underline the multifunctional performance of FeCoNiMnCu HEA, highlighting its strong potential for use in advanced nuclear reactor components and radiation shielding technologies.
AtıfScopus10OpenAlex6İncele - MakaleAçık Erişim2025Scopus SJRQ2Determination of cardiometabolic risk in pre- and post-menopausal women
Orhan, İlksen; Koçak, Hatice Serap; Kaplan, Emine
Objective: The study was designed to determine and compare the cardiometabolic risk in premenopausal and postmenopausal women. Methods: Data were collected using cross-sectional and correlational study. In this study, the sociodemographic characteristics, anthropometric measurements, and biochemical parameters of menopausal women were examined. Results: The average age of menopausal women is higher compared to premenopausal women. Menopausal duration, number of children, daily cigarette consumption, body weight, body mass index (BMI), waist circumference, hip circumference, waist-to-hip ratio, systolic and diastolic blood pressure, fasting blood glucose, hemoglobin, AST (aspartate aminotransferase), and Framingham risk score are higher in menopausal women compared to premenopausal women. Conversely, height, HDL (high-density lipoprotein) level, LDL (low-density lipoprotein) level, TSH (thyroid-stimulating hormone), ALT (alanine aminotransferase), HbA1c (glycated hemoglobin), serum albumin, and visceral adiposity index (VAI) values are lower in menopausal women compared to premenopausal women. Conclusion: These findings indicate changes in the metabolic profiles of menopausal women. This study could serve as an important resource for assessing the health status of menopausal women and for implementing appropriate measures. Clinical trial number: not applicable.
AtıfScopus4WoS4OpenAlex5İncele - MakaleAçık Erişim2026Scopus SJRQ1Generative Artificial Intelligence in Education: Conceptual Dimensions, Trends, and Research Directions
Akti Aslan, Seda; Ayaz, Ahmet; Ozyurt, Ozcan; Aslan, Alper
Research into generative artificial intelligence (GenAI) in the field of education has been growing rapidly in recent years. The rapid expansion of the literature has necessitated a systematic examination of the field. In this study, the thematic structure of GenAI research in the field of education during the 2023–2025 period was examined. Given the need to work with a large-scale dataset comprising 15,036 studies, a Latent Dirichlet Allocation (LDA)-based topic modelling analysis was selected. A search conducted on Scopus resulted in the inclusion of 15,036 studies in the analysis. The LDA analysis identified 12 prominent topics based on consistency scores. Descriptively, these prominent topics were grouped under four broad thematic areas. Among these axes, the technical axis holds the largest share (25%). It was observed that whilst technical topics were on the rise during the 2023–2025 period, topics such as ethics and chatbots showed a relative downward trend. The observed trends suggest that scholarly attention is increasingly directed towards technically oriented research. The findings also indicate a need for theoretical frameworks to ensure pedagogical depth. It is anticipated that the study’s findings will serve as an important reference point for future research. © The Author(s) 2026. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License (https://creativecommons.org/licenses/by-nc/4.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).
- MakaleAçık Erişim2026Scopus SJRQ2Thickness- and Binder-Chemistry-Dependent Structural, Mechanical, and Tribological Performance of HVOF-Sprayed WC-Co and WC-Co-Cr Coatings on High-Speed Steel
Macit, Cevher Kursat; Aksakal, Bünyamin; Ayık, Merve; Gürgenç, Turan; Aslan, Naim
High-velocity oxy-fuel (HVOF) spraying was used to deposit WC-Co and WC-Co-Cr coatings on high-speed steel in order to determine how binder chemistry and coating thickness jointly control load support, friction, and dry sliding wear resistance. Nominal 50 and 100 µm coatings were compared within the same substrate framework by XRD, FT-IR, SEM/EDX, cross-sectional image analysis, Vickers hardness testing, dry sliding wear testing, and post-wear SEM/EDX. The coatings retained WC as the dominant crystalline phase, while weak overlapping features were associated with binder-rich regions and limited decarburization products. Cross-sectional observations confirmed continuous coating build-up close to the nominal thicknesses and low apparent dark-feature/porosity fractions. All WC-based coatings increased the effective hardness and reduced mass loss relative to uncoated HSS. Among the tested conditions, WC-Co-Cr-100 provided the highest effective hardness and the lowest mass loss after 1000 m sliding, whereas WC-Co-100 produced the lowest mean coefficient of friction. The results show that low friction and high wear resistance are not governed by identical mechanisms: WC-Co favours interfacial shear reduction, while the thicker Cr-containing coating provides superior resistance to material removal through improved carbide retention, binder stability, and coating-scale load support.
- MakaleAçık Erişim2025Scopus SJRQ1Effects of inspiratory muscle training on physical fitness in cystic fibrosis: a systematic review and meta-analysis
Aksel-Uylar, Aydan Asli; Topcuoglu, Ceyhun; Saglam, Melda; Vardar-Yagli, Naciye
Background: Cystic fibrosis (CF) is a multisystem disease primarily affecting the lungs. It impacts physical fitness due to increased bronchial secretions and exercise intolerance. Inspiratory muscle training (IMT) is recommended as a pulmonary rehabilitation approach. Therefore, we aimed to examine the effect of inspiratory muscle training on health-related physical fitness in CF. Methods: Articles were searched in five databases from inception to June 2025. All randomized controlled trials comparing IMT with a control group in individuals with cystic fibrosis were included. Four randomized controlled trials involving a total of 90 individuals with CF met the inclusion criteria. Results: A significant difference was found in the change in maximal work capacity, maximal minute ventilation, and exercise duration during the exercise test in the IMT group compared to the control group. However, no significant difference was observed in the change in maximal oxygen uptake, 6-minute walk test distance, and oxygen saturation during the 6-minute walk test between the IMT group and the control group. Conclusion: The therapeutic effectiveness of IMT for physical fitness is still uncertain. The evidence is not enough to assess how IMT can be used to enhance health-related physical fitness in CF. Further research should explore the optimal intensity and duration of IMT training needed to improve cardiorespiratory fitness. Additionally, future studies should evaluate how effective IMT is when examining its impact on health-related physical fitness.
- MakaleYalnız künye2025Scopus SJRQ1Bridging experiment and simulation: Image processing-driven FEA of carbon fiber powder reinforced LDPE
ARIKAN, Volkan; DOGAN, Akar
Short fiber-reinforced polymers are widely used in engineering applications due to their improved mechanical performance and processability. However, accurately predicting the elastic behavior of such composites remains a challenge, especially when fibers are randomly distributed and lack defined orientation. To address this, this study investigates the mechanical properties of composite materials developed by incorporating carbon fiber powder (CFP) into a low-density polyethylene (LDPE) matrix at different reinforcement ratios (3 %, 6 %, and 9 %). The effects of CFP content on elastic modulus, tensile strength, and ductility were examined experimentally and through finite element analysis (FEA). Scanning electron microscopy (SEM) was used to analyze the microstructure, and image processing techniques were applied to quantify fiber orientation, which was then integrated into the FEA framework (Oriented FEA). Results indicate that CFP addition increases stiffness and tensile strength while reducing ductility, with 3 % CFP specimens showing the most favorable balance of mechanical properties. The proposed image-based orientation modeling approach provides improved simulation fidelity and offers a scalable methodology for evaluating the mechanical behavior of short fiber-reinforced composites.
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2026Scopus SJRQ3Oxidative Stress Responses induced by Yttrium in Gammarus pulex at Increasing Temperatures
Aydın, Ayşe Nur; Serdar, Osman
In parallel with the increase in the need for raw materials used in industry, the area and amount of use of Rare Earth Elements are also increasing. Yttrium (Y), which is used as a raw material source, is thought to form residues in the environment. Gammarus pulex individuals were selected as a model organism to investigate the effects of Yttrium on the environment and aquatic organisms. G. pulexes were exposed to Y at different temperatures (16, 18, and 20 °C) and concentrations (25, 100, and 500 µg/L) for 96 hours and samples were taken at 24 and 96 hours for biochemical analyses. For biomarker analysis, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities, thiobarbituric acid (TBARS) and glutathione (GSH) levels were performed using CAYMAN ELISA kit. Study data revealed that SOD and CAT activities increased significantly with increasing temperature and exposure concentration, while GPx activity showed an irregular response; in contrast, no significant change was observed in TBARS levels at 16 °C, while the increase in TBARS and significant changes in GSH levels at 18 and 20 °C indicate that oxidative stress becomes more pronounced at high temperatures. Copyright Aydın,, A. N. & Serdar, O.
- MakaleYayıncıda açık erişim2026Scopus SJRQ1Explainable AI-based deep learning architectures for hydrogen prediction in biomass syngas and photocatalysis processes: Towards a sustainable and efficient energy economy
Imak, Andaç
This study, focusing on sustainable energy production and particularly the hydrogen (H2) economy, presents an advanced artificial intelligence (AI) framework for accurately predicting H2 production from sucrose photocatalysis catalyzed by LaFeO3 (GLFO) and the H2 concentration in syngas derived from biomass conversion. The research was conducted along two main directions: (i) deep learning (DL) architectures comprising nine specially designed recurrent neural network-based models and (ii) six conventional machine learning (ML) algorithms. For both H2 production systems, the best-performing models were identified and further interpreted using explainable AI (XAI) based on SHapley Additive exPlanations (SHAP). Among all investigated algorithms, a hybrid One-dimensional Convolutional Neural Network–Bidirectional Long Short-Term Memory–Bidirectional Gated Recurrent Unit (1D-CNN–BiLSTM–BiGRU) model demonstrated the highest predictive performance. Using 10-fold cross-validation, the proposed model achieved outstanding accuracy, with an R2 value of 0.9987 ± 0.0011 for photocatalytic H2 production prediction and 0.9980 ± 0.0006 for syngas H2 concentration prediction. These results highlight the potential of the proposed framework as a precise, reliable, and practical methodological approach for modeling and optimizing complex thermochemical energy systems.
- MakaleYalnız künye2025Scopus SJRQ2The Relationship Between Employment Guilt and Psychological Resilience Levels of Working Mothers
Orhan, İlksen; Ünal, Esra; Ağralı, Cansu
Psychological resilience is a significant factor affecting feelings of guilt, as it helps mothers maintain a better balance between work and family responsibilities. This study was conducted to identify the relationship between employment guilt and the psychological resilience levels of working mothers. The research involved 483 working mothers residing in Osmaniye province, Turkey, who were employed in various fields. In this cross-sectional correlational study, data were collected online via Google Forms using the Personal Information Form, the Maternal Employment Guilt Scale, and the Brief Resilience Scale. The results of this study suggest that as the psychological resilience levels of working mothers increased, their employment guilt levels decreased. The results from this research can be used to identify potential interventions that could mitigate the negative effects of employment guilt on psychological resilience.
AtıfScopus4WoS4OpenAlex5İncele - MakaleAçık Erişim2026Scopus SJRQ2Relative Efficiencies of Live, Dry and Mixed Food Diets for Larval Rearing of Tigris Scraper (Capoeta umbla) and the Influence of Stocking Density on Fry Growth Characteristics
Gün, Abdulselam; Kızak, Volkan; Gündüz, Fatih
In this research, larval growth features by applying different diets and growth characteristics of fry at different stocking densities were studied under controlled conditions for the Tigris scraper (Capoeta umbla). In the first experiment, the growth and survival rates of Tigris scraper postlarvae were evaluated under three different diet regimes over 21 days. The highest mean total length was 24.04±0.27 mm in the group L1 fed solely Artemia nauplii, and the lowest mean total length was 17.89±0.16 mm in the group L2 fed only dry feed. The highest mean specific growth rate was in the L1, and the lowest mean specific growth rate was in the L2. In the second experiment in which the growth characteristics of fry were investigated at different stocking densities for 98 days, the highest mean live weight was found in S1 with 2.819±0.157 g and the lowest mean live weight was determined as 0.859±0.073 g in S5. The highest mean specific growth rate was in S1, while the lowest rate was in S5. High stocking densities were found to be disadvantageous for growth of C. umbla fry. The findings suggest that successful rearing of Tigris scraper postlarvae and fry is feasible under controlled conditions.
- MakaleAçık Erişim2026Scopus SJRQ1Failure of a Code-Compliant Reinforced Concrete Building: Damage Patterns and Nonlinear Seismic Response
Onat, Onur; Karaşin, İbrahim Baran; Yön, Burak; Varolgüneş, Sadık; Öncü, Mehmet Emin; Uslu, Ali
This study investigates the seismic performance limitations of a newly constructed reinforced concrete building that collapsed during the 6 February 2023 Kahramanmaraş–Elbistan earthquake despite formal compliance with current seismic design requirements. Beyond the specific earthquake event, the study addresses a broader scientific problem: the limited understanding of the relationship between observed damage mechanisms and nonlinear dynamic response in mid-rise reinforced concrete buildings. The first part classifies recurring structural and non-structural damage patterns identified in newly constructed RC residences. The second part presents a nonlinear fiber-based static and dynamic analysis of a collapsed mid-rise building. Nonlinear dynamic analyses were conducted using ground motion records scaled to match the site-specific elastic design spectrum defined by TBDY 2018, corresponding to predefined seismic performance levels rather than an incremental dynamic analysis framework. The results indicate that an extremely low shear wall–to–floor area ratio (0.0357%) combined with asymmetric vertical element distribution significantly amplified torsional response and local shear demands. Nonlinear dynamic analyses showed that critical shear walls exceeded Collapse Prevention limits under DD2-level excitation, while system-level shear contribution limits remained within code-defined thresholds. Dynamic base shear demand corresponded to approximately 30% of the maximum nonlinear capacity obtained from pushover analysis, indicating that localized member failure rather than global strength deficiency governed the collapse mechanism. The analytically identified critical members were consistent with the observed collapse configuration, particularly at the soft ground story. The findings demonstrate that prescriptive code compliance alone may not ensure satisfactory seismic performance when structural irregularities, torsional amplification, and detailing deficiencies coexist. The results are consistent with damage patterns reported in other recent destructive earthquakes and contribute to improving the understanding of collapse mechanisms in code-compliant RC buildings.
AtıfScopus4OpenAlex7İncele - MakaleYayıncıda açık erişim2026Scopus SJRQ1Radon anomalies environmental radiation transfer and radiological risk assessment in a fault controlled Lake system
Dartay, Mürşide; Yılmaz, Mücahit; Kırat, Güllü
This study investigates the coupling between radon (222Rn) anomalies, seismic activity, hydrogeochemical transport, and radiological risk in Lake Hazar, an active fault controlled lake located along the East Anatolian Fault Zone (EAFZ), Türkiye. Soil gas and dissolved 222Rn concentrations were periodically monitored on a monthly basis from September 2024 to August 2025 using a DURRIDGE RAD7 detector coupled with RAD H2O accessories and the results were evaluated with regional seismicity within a 50 km radius. Natural radionuclide activities (40K, 238U, and 232Th) were determined using 2″ × 2″ NaI(Tl) well-type gamma spectrometry detector. 222Rn anomalies were assessed using μ + σ, μ + 2σ thresholds, the Standardized Radon Index (SRI), and the Dobrovolsky preparation radius model. Soil 222Rn ranged from 87.6 to 541.8 Bq/m3, with the highest value (SRI = 2.81) recorded in September 2024, approximately one month before the Mw 6.0 earthquake in October 2024. Although this temporal coincidence is consistent with previous observations reported for tectonically active regions, the present dataset does not allow a definitive causal interpretation. Dissolved 222Rn varied from 34.1 to 69.8 Bq/L and showed delayed but detectable responses during periods of Mw ≥ 5 seismic activity. Radiological indices calculated for fish tissues remained far below international safety thresholds: Hin and Hex were < 1, Raeq values were substantially lower than the recommended limit of 370 Bq/kg, and absorbed dose rates were below the global average value of 59 nGy/h reported by UNSCEAR. In addition, annual effective dose values from fish muscle consumption remained well below the public exposure limit of 1 mSv/year recommended by ICRP, and ELCR values were within the low risk range commonly used in environmental radiological assessments. These findings indicate that active fault controlled lake systems may provide integrated environmental settings where tectonic stress, 222Rn migration, aquatic radionuclide transfer, and radiological exposure processes interact. Novelty statement: This study presents an integrated environmental investigation of soil gas and dissolved water 222Rn variability, radionuclide transfer in aquatic biota, and radiological risk assessment within the tectonically active Hazar Lake system located on the East Anatolian Fault Zone (EAFZ), Türkiye. The novelty of the present study lies in the following aspects: • Simultaneous evaluation of soil and dissolved water 222Rn anomalies together with seismic activity in a fault controlled lake ecosystem. • Application of the Standardized Radon Index (SRI) approach for normalized temporal interpretation of radon anomaly behavior in both soil gas and aqueous environments. • Integration of tectonic hydrogeochemistry with environmental radioactivity and aquatic radionuclide transfer assessment. • Combined investigation of radon anomaly behavior and radionuclide accumulation in fish tissues within the same tectonically active environmental system. • Inclusion of radiological risk indices (Hin, Hex, Raeq, Iγ, AGED) together with internationally accepted reference values for environmental and public health interpretation. • Development of a multidisciplinary environmental monitoring framework linking lithospheric, hydrospheric, and biospheric processes in active fault controlled lake environments. To the best of our knowledge, this is among the limited studies combining 222Rn anomaly monitoring, aquatic radionuclide transfer, and radiological risk assessment within an integrated tectonic lake ecosystem framework.
- MakaleYalnız künye2026Scopus SJRQ3Enrichment factor (EF) of REEs in soil fractions of different grain sizes: Malatya–Kuluncak, Başören Village
Kirat, Güllü; Erdem, Özlem
This study investigated the enrichment factor (EF) and geochemical relationships of rare earth elements (REEs) in different grain size fractions of soils collected from Başören village, Kuluncak district, Malatya province, Türkiye. A total of 22 surface soil samples were collected and separated into five grain size fractions (< 75, 75–150, 150–180, 180–250, and > 250 μm), yielding 110 samples. Concentrations of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Yb, Lu, and Y were determined by ICP-MS. EF values were calculated using Al as the reference element, and Pearson correlation was applied to evaluate the relationships between REEs. Strong positive correlations were observed among most REEs (r = 0.999–1.000, p < 0.01), whereas weaker correlations were shown between Eu and Gd elements and La, Ce, Pr, Nd, Sm, Tb, Dy, Ho, Yb, Lu, and Y elements. Moderately positive relationships were determined between Al and REEs, with coefficients of determination (R2) ranging from approximately 0.33 to 0.54, indicating that REE distributions are primarily controlled by aluminosilicate minerals and fine-grained fractions. EF values varied between sampling areas and grain size fractions. While negligible to moderate enrichment was observed in most samples, significant to very high enrichment was observed in some samples, particularly for Gd, Tb, Dy, Ho, and Yb. Samples T16 and T20 showed the highest enrichment levels, with Gd reaching very high enrichment classes (EF = 20–40). The results show that the spatial distribution and enrichment patterns of rare earth elements are largely influenced by lithogenic sources and grain size-dependent mineralogical characteristics.
- MakaleAçık Erişim2025Scopus SJRQ3Quality Culture and Impact Dynamics in Educational Institutions: A Qualitative Analysis Based on the Experiences of School Administrators
Yaraş, Zübeyde; Gündüzalp, Seda
This study highlights the role of leadership in shaping quality processes within educational institutions, focusing on the development of a quality culture in schools in the K -12 system (from kindergarten to 12th grade). It explores the connection between leadership discourse and organizational transformation. Using a qualitative, phenomenological design, the study involved 22 school principals from preschool to high school, selected through purposive sampling. Data collected through semi -structured forms were analyzed using content analysis. Findings show that school leaders believe quality processes positively influence instructional quality, student development, organizational success, and culture. Leadership communication, shared values, and stakeholder involvement were seen as key to embedding quality in school functions. The study emphasizes the importance of quality culture in areas such as management processes, teaching practices, human resources, and quality control. Strategies like reward systems, promoting innovation, and effective talent management were identified as essential for fostering a quality culture. Challenges faced by administrators in this process were also revealed. To overcome these, suggestions include using positive reinforcement and offering training in quality management. Overall, the study integrates theoretical perspectives on leadership with practical insights into communication and strategy, concluding that a strong quality culture has a significant impact on educational policy.
