Yayınlar
Koleksiyondaki öğeler
- MakaleAçık Erişim2025Scopus SJRQ1Protective Effects of Dexmedetomidine and Amifostine Against Radiotherapy-Induced Kidney Injury
Batcik, Sule; Tumkaya, Levent; Dil, Eyup; Kazancioglu, Leyla; Gaygusuz, Elif; Yazici, Zihni Acar; Ozden, Zulkar; Kilinc, Kagan; Mercantepe, Tolga
Backgrounds: Approximately 18 million individuals were diagnosed with cancer in 2018. The rate is predicted to exceed 22 million by 2030. Radiotherapy is an essential part of cancer therapy, with well documented local and systemic side effects, including oxidative stress and apoptosis. Kidney tissues are also exposed to the deleterious effects of radiotherapy, resulting in acute or chronic kidney function impairment. This study compared the effects of the potent selective α2-adrenoreceptor agonist dexmedetomidine and amifostine on oxidative stress and apoptosis in kidney damage induced by x-irradiation in rats. Methods: Forty Sprague Dawley rats were assigned into five groups: control, x-irradiation, x-irradiation + amifostine, x-irradiation + dexmedetomidine 100 µg/kg, and X-ray irradiation + dexmedetomidine 200 µg/kg. Results: Necrotic tubules and degenerative Bowman’s capsules were present in the x-irradiation group. An increase was determined in malondialdehyde (MDA), Cleaved Caspase-3, and 8-OHdG levels compared to the control group (p ≤ 0.05). In contrast, there was a decrease in necrotic tubules, degenerative Bowman’s capsules, and the levels of MDA, Cleaved Caspase-3, and 8-OHdG in the amifostine and dexmedetomidine 100 µg/kg and 200 µg/kg treatment groups (p ≤ 0.05). Conclusions: Alpha 2 adrenergic receptor agonists exhibit protective effects against kidney injury induced in association with x-irradiation by reducing oxidative stress and apoptosis.
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- MakaleAçık Erişim2025Scopus SJRQ1How do green hotel practices affect guests’ behavioral intentions? A PLS-SEM approach; [Como as práticas hoteleiras verdes afetam as intenções comportamentais dos hóspedes? Uma abordagem PLS-SEM]
Genç, Gökhan; Zengin, Burhanettin
This study examines how guests’ perceptions of green hotel practices (GHP) shape their behavioral intentions, drawing on the Theory of Planned Behavior. It explores the extent to which eco-friendly practices influence guests’ loyalty and their likelihood of recommending hotels that prioritize sustainability. Data were collected from 642 hotel guests aged 18 and over who had previous experience with green hotel practices. An online survey was employed, and the data were analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM) with bootstrapping techniques to assess the relationships among guests’ perceptions of GHP, satisfaction, and behavioral outcomes. The findings indicate that favorable perceptions of GHP strongly predict guest loyalty and recommendation intentions, with satisfaction as a critical mediator. These results highlight the pivotal role of sustainable practices in fostering positive guest experiences and behaviors in the hospitality industry. The study offers practical insights for hotel managers, enabling them to design and implement effective sustainability strategies that enhance guest satisfaction and loyalty. Furthermore, it contributes to the literature on sustainable tourism by providing robust empirical evidence on the influence of GHP on guest behavior, thus addressing a key gap in hospitality management research.
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- MakaleAçık Erişim2025Scopus SJRQ2Research of Peganum harmala: Phytochemical Content, Mineral Profile, Antioxidant, Antidiabetic, Anticholinergic Properties, and Molecular Docking
İzol, Ebubekir; Turhan, Münire; Yapıcı, İsmail; Necip, Adem; Abdullah Yılmaz, Mustafa; Zengin, Gökhan
Peganum harmala is a significant medicinal, aromatic plant used in traditional medicine and the subject of many studies. In this study, the phytochemical compound and mineral profile of the plant's ethanol extract were identified quantitatively. Antioxidant properties were determined by total phenolic and flavonoid content, FRAP, DPPH, CUPRAC, ABTS, metal chelating, and phosphomolybdenum assays. Antidiabetic, anticholinergic, and skin care properties were specified by the inhibition of tyrosinase, α-glucosidase, α-amylase, butyrylcholinesterase (BChE), and acetylcholinesterase (AChE) enzymes, respectively. In addition, binding interactions of major phytochemicals with all enzymes were investigated by molecular docking studies. The phytochemical compound of the extract contained significant bioactive components such as acacetin, gentisic acid, p-coumaric acid, quinic acid, rutin, apigenin, and chrysin, while the mineral profile was rich in salt elements. AChE, BChE, tyrosinase, α-amylase, and α-glycosidase enzyme inhibitor results were determined as 2.99 mg GALAE/g, 4.14 mg GALAE/g, 35.8 mg KAE/g, 2.76 mmol ACAE/g, and 1.20 mmol ACAE/g, respectively. As a result, it was identified that it had antioxidant properties and strongly inhibited all enzymes except tyrosinase. The docking scores of major bioactive phytochemicals were found to be high. The best binding pose was obtained by docking acacetin into the active site of AChE (PDB: 4EY7), BChE (PDB: 4BDS), α-glucosidase (PDB: 3WY1), α-amylase (PDB: 6GXV) and tyrosinase (PDB: 2Y9X) receptors. Docking score values were calculated as −10.4, −9.2, −8.8, −7.8, and −7.4 kcal/mol, respectively. Thus, it was revealed that P. harmala has an important potential in drug research and treatment of some diseases.
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- BildiriYalnız künye2025Improving Skin Lesion Classification with Pretrained Deep Learning Models
Almasani, Heba; Ture, Hayati
Skin cancer is the most common type of cancer. Cancer can be defined as a disease characterized by the uncontrolled division and spread of cells. As with other types of cancer, early diagnosis and treatment play a crucial role in combating skin cancer. Since diagnosis is made through visual examination, factors such as the level of expertise and image artifacts negatively affect diagnostic accuracy and slow down the process.Computer-aided applications used to analyze such images provide faster and more accurate results. Additionally, these methods eliminate factors that reduce diagnostic accuracy during the classification and segmentation of skin lesions.This study classifies skin cancer to benign or malignant using deep learning and machine learning methods. In particular, Convolutional Neural Networks (CNNs) have shown promising results in medical image classification. The study evaluates six pre-trained CNN models - VGG16, EfficientNetB7, EfficientNetV2L, DenseNet, ConvNeXtBase and MobileNet - for binary skin lesion classification using the ISIC 2019 dataset. The study first preprocesses and balances the data to enhance performance. The results indicate that the ConvNeXtBase model achieved the highest success with accuracy rate of 84.63% after balancing the data that we have.
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- MakaleAçık Erişim2024Scopus SJRQ1The Effect of Heat Treatment on the Mechanical Properties and Oxidation Resistance of AlSi10Mg Alloy
Beder, Murat; Akçay, Serhatcan Berk; Varol, Temel; Çuvalcı, Hamdullah
In this study, the microstructure, hardness, tensile strength, and dry wear properties of the cast AlSi10Mg alloy as well as the effects of processing parameters on the oxidation behavior of this alloy were investigated. In this context, AlSi10Mg (wt%) alloy was produced by gravity die casting method, and then, air cooling, quenching, and T6 treatment were applied. The microstructure of the alloy was investigated using an optical microscope, SEM, and EDS. Additionally, thermogravimetric analysis (TGA) was used to determine the effect of processing parameters on the oxidation behavior of the samples. The friction and wear properties of the alloy were investigated using a ball-on-disk wear test device. It was founded that the as-cast AlSi10Mg alloy's microstructure contained phases of α(Al), Si, and β-Mg2Si. It has been observed that the microstructure of the cast AlSi10Mg alloy gradually turns into a spherical form when quenching and air-cooling heat treatments are applied. Also, T6 heat treatment led to further spheroidization of Si particles, formation of β-Mg2Si precipitates, and elimination of the Chinese script morphology of the β-Mg2Si phase. It was observed that the yield strength of the AlSi10Mg alloy in the as-cast state decreased negligibly compared to the air-cooled state, while there was an increase of up to 70% in the aging-treated condition. The results show that the tensile strength of the as-cast AlSi10Mg alloy increased by 115% after aging. Additionally, it was found that the AlSi10Mg alloy's wear resistance increased with the aging process.
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- MakaleYayıncıda açık erişim2025The Effect of Heavy Metals in Mining Emissions on Worker’s Blood Lead Levels: A Case Study of The Gumushane Zn-Pb Mine, Turkey
Bozbeyoğlu, Pınar; Doğan, Onur; Budak, Burhan
The wastewater from mining facilities contains toxic elements such as arsenic (As), cadmium (Cd), chromium (Cr), manganese (Mn), zinc (Zn), and lead (Pb). If not disposed of correctly, it can lead to environmental pollution in case of accidents or overflow. Lead-zinc mining activities pose a significant risk of high blood lead levels (BLLs) among workers. Therefore, monitoring the blood lead levels of workers exposed to these heavy metals, especially lead, is crucial. This study aims to determine the levels of potentially harmful elements in the wastewater dam of the largest Zn-Pb mine in the Black Sea Region. It also seeks to assess the environmental and human health risks comprehensively. Additionally, the study aims to establish a relationship between the levels of lead in the mining wastewater in Gumushane and the lead levels accumulated in the blood of workers exposed to this metal. The study analyzed heavy metals such as As, Zn, Cu, Sb, and Pb in mining wastewater using Inductively Coupled Plasma – Mass Spectrometer (ICP-MS). The results indicated high levels of Pb in the studied wastewater. Furthermore, the blood lead levels of workers in the mining area (n=30; mean: 7.42 μg/dL) exceeded background levels (>40 μg/dL). These results suggest a significant relationship between the presence of lead in wastewater and high lead levels in the blood of individuals with high exposure to concentrated lead.
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İncele - MakaleAçık Erişim2025Scopus SJRQ2Comprehensive study on the role of mycrisparite in enhancing strength, stability, and microstructural traits of self-compacting mortars
Etli, Serkan; Yılmaz, Tekin
The present research work aims at promoting the mechanical, durability and microstructure performances of self-compacting mortars (SCMs) and lessening the cement production-induced costs and environmental difficulties, by replacing binder with definite proportions (2.5–15%) of MS. To achieve these goals, the compressive and flexural strength (UCS, FS), freeze–thaw (F–T), sorptivity (Sp), MIP (tP, psD) and SEM tests were conducted on SCMs cured for diverse (7–90 days) ages. The outcomes unearthed that replacing binder with MS at small proportions boosted the UCS/FS performances of SCMs. These improvements in strength performance compared to MS-0 were more spectacular in MS-2.5, which produced higher UCS and FS of 8.6–21.0% and 10.0–25.7%, respectively at all curing ages. Similarly, the same SCMs, which betrayed lower UCS- (10.3 < 16.7) and FS-losses (31.6 < 41.0) than the control at the end of the 200-cycle F–T test, were able to remain more endurance against F–T deterioration. Besides, MS replacement up to 10% enabled the SCMs to exhibit lower tP- (up to 11.2%) and Sp values (up to 61.2%) by ameliorating the psD (refining the larger pores into finer pores). The current research can be consequently commented to provide more beneficial SCM design on both strength/stability and microstructure, and cost and environmental troubles for the building industry.
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- MakaleYalnız künye2025Scopus SJRQ1Integrated Geophysical Survey (GPR, ERT and Magnetometry) at the Kalehisar Archaeological Site in Central Anatolia
Kayın, Sercan; Aydın, Nedim Gökhan; Apaydın, Orhan; İşseven, Turgay
Kalehisar Archaeological Site, located near Mahmudiye Village in the Alaca district of Çorum, provides important insight into the Anatolian Seljuk period and 13th–14th century settlements in Central Anatolia. The main objective of this study is to determine the location and depth of possible buried archaeological remains within the archaeological site. This approach not only guides future excavations but also contributes to a more comprehensive understanding of settlement patterns and architectural practices during the Seljuk period. To achieve this, a comprehensive geophysical survey was conducted, employing magnetometry, electrical resistivity tomography and ground penetrating radar methods. Spectral analysis was used to interpret magnetic anomalies and identify potential buried features. Ground penetrating radar measurements provided high-resolution subsurface imaging, allowing for the detection of fine-scale stratigraphic variations and potential shallow buried remains. Electrical resistivity tomography helped identifying subsurface structures with contrasting resistivity down to 10-m depth. Integrated geophysical results revealed wall continuations extending from the excavation area, alongside other buried features such as ceramic/pottery kilns and a possible mosque in a few depths from the surface. These findings are consistent with Seljuk-era settlements and can aid future excavations by optimizing resources and preserving archaeological integrity.
- Derleme MakaleYayıncıda açık erişim2024Scopus SJRQ1From Garden to Pillow: Understanding the Relationship between Plant-Based Nutrition and Quality of Sleep
Arslan, Neslihan; Bozkır, Eda; Koçak, Tevfik; Akin, Meleksen; Yilmaz, Birsen
The effect of diet on sleep quality has been addressed in many studies; however, whether/how plant-based diets (PBDs) impact sleep-related parameters has not been explored in detail. This review aims to give an overview of the components of PBDs and the possible mechanisms through which PBDs may improve sleep quality. Studies have indicated that diets such as PBDs, which are typically high in fruits, vegetables, nuts, seeds, whole grains, and fiber, are associated with better sleep outcomes, including less fragmented sleep and improved sleep duration. Several mechanisms may explain how PBDs impact and/or improve sleep outcomes. Firstly, PBDs are characteristically rich in certain nutrients, such as magnesium and vitamin B6, which have been associated with improved sleep patterns. Secondly, PBDs are often lower in saturated fats and higher in fiber, which may contribute to better overall health, including sleep quality. Additionally, plant bioactive compounds like phytochemicals and antioxidants in fruits, vegetables, and herbs may have sleep-promoting effects. According to available data, PBD and Mediterranean diet elements promise to enhance sleep quality; however, it is crucial to note that diets should be customized based on each person’s needs.
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- MakaleYalnız künye2025Scopus SJRQ2Remanent magnetization and magnetic relaxation in Bi:2223/ag tapes fabricated by the Powder-in-Tube (PIT) method at 30 K
Düzgün, İbrahim; Çelebi, Selahattin
In this study, the remanent magnetization and magnetic relaxation behaviour of Bi-2223/Ag superconducting tapes fabricated using the Powder-In-Tube (PIT) method were investigated. Measurements were conducted at a fixed temperature of 30 K, both under various field cycling amplitudes and in constant magnetic field conditions to analyse time-dependent magnetization. The remanent magnetization values obtained after full magnetic cycles were normalized and compared with theoretical predictions based on the extended critical state model. Additionally, magnetic relaxation curves were recorded at 30 K to evaluate flux creep characteristics. A clear logarithmic decay in magnetization was observed, indicating the coexistence of at least two distinct pinning regimes. These results contribute to a deeper understanding of flux dynamics and magnetic stability in Bi-2223/Ag PIT tapes for practical superconducting applications.
- MakaleYalnız künye2025Scopus SJRQ3Narrative empathy in young adult literature: Am I normal yet?
Demir, Nalan
Mental health issues are increasingly common in modern societies, yet public awareness has not kept pace. The invisibility of psychological disorders and fear of stigma contribute to this gap. Early detection is vital, especially among young people. Literature with its impact on emotional and cognitive development, can help raise awareness and provide support. This study examines Holly Bourne’s Am I Normal Yet? through the lens of narrative empathy to explore how fiction can shape perceptions of mental illness. It analyzes the novel’s first-person narration and embodied narration, which may evoke empathy for the protagonist experiencing obsessive-compulsive disorder. These techniques can encourage emotional engagement and foster compassionate attitudes toward mental health challenges. Moreover, such literature may offer validation and solidarity to struggling readers. Ultimately, this research highlights young adult fiction's potential to enhance mental health literacy and act as an empathetic bridge between individual experience and societal understanding.
- MakaleAçık Erişim2024Scopus SJRQ1Improving brain tumor classification with combined convolutional neural networks and transfer learning
İncir, Ramazan; Bozkurt, Ferhat
Brain tumors pose a serious threat, causing the deaths of thousands of people worldwide, and can lead to life-threatening consequences when not accurately diagnosed. The classification of brain tumors and the determination of correct treatment strategies are crucial, yet this process encounters various challenges. These tumors originate from different cell types and exhibit diversity in growth rates, histological features, and genetic structures. Some may show similarities at the microscopic level, complicating classification and making diagnosis and treatment challenging. The examination of brain MR images is a widely used method in diagnosing brain tumors. However, occasional misdiagnosis of tumors can lead to ineffective responses to treatments and reduced chances of survival for patients. Traditional machine learning classifiers require manually determined features, which is quite time-consuming. On the other hand, deep learning is highly effective in feature extraction and has recently been widely preferred in classification. In this context, the effectiveness of transfer learning architectures in brain tumor diagnosis was evaluated. Six different transfer learning architectures, including ResNet-50, MobileNet, VGG16, Inception-V3, DenseNet-121, and EfficientNetV2-M, were used in this study. A public MRI dataset was used for model validation and comparison with similar studies. To address the imbalance in the number of images among classes in the dataset, data augmentation techniques such as random rotation were applied during data preprocessing. Experiments revealed that the EfficientNetV2-M model outperformed other architectures with a 98.01% accuracy rate. Additionally, the study aimed to create a new model with more comprehensive feature extraction and generalization ability by combining the advantages of multiple models in different combinations. In this context, combinations of EfficientNetV2-M architecture with Inception-V3 and DenseNet-121 architectures were formed. Through these combinations, a concatenation-based EfficientNetV2-M + Inception-V3 model achieved a 98.41% accuracy value. It was observed that the proposed concatenation-based model outperformed advanced methods in improving medical imaging techniques and patient outcomes.
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- MakaleAçık Erişim2024Scopus SJRQ3Functional outcome and single hop test results of ACL reconstruction in athletes at a follow-up of 6 and 12 months: modified all-inside versus conventional hamstring autograft
Yoldaş, Burak; Yılmaz, Ali Kerim; Yılmaz, Coşkun; Akdemir, Enes; Anıl, Berna; Benli, Merve Demir; Genç, Ahmet Serhat; Kehribar, Lokman
Anterior cruciate ligament (ACL) tears are injuries with a high incidence in athletes, and ACL reconstruction (ACLR) is a surgical treatment orthopedists perform. This study aims to compare the 6 and 12 months post-op results of single leg hop tests (SLHT) performed in multidirectional conventional semitendinosus/gracilis (ST/G) and modified all inside (MAI) ACLR techniques on both sides and the limb symmetry indexes (LSI) of both techniques. This study evaluated a retrospective cohort of 50 male athletes who applied MAI (n = 23) and traditional ACLR ST/G (n = 27) techniques. Functional knee strength of the participants on both sides was measured with different SLHTs at 6 and 12 months postoperatively. The SLHT included medial side (MSTH), triple hop (TH), medial rotation (90◦) (MRH), crossover triple (CH) ve the single hop (SH) hop for distance. Both ACLR techniques showed significant improvement in mean Tegner, International Knee Documentation Committee (IKDC) and Lysholm scores preoperatively and at 6 and 12 months postoperatively (p < 0.05). For MAI and ST/G techniques, there was no significant difference in the results of SLHTs at 6 and 12 months for both the operated and non-operated sides (p < 0.05). Significance was found only in the MRH test of the non-operated side (p < 0.05). There was no significant difference in SLHT scores between the operated and non-operated sides at 6 and 12 months postoperatively (p > 0.05). There was no difference in LSI scores between techniques (p < 0.05). Our study revealed similar LSI rates in ST/G and MAI techniques at 6 and 12 months, suggesting that MAI technique can be used as a functional ACLR technique for athletes.
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- MakaleAçık Erişim2025Scopus SJRQ2Concurrent Validity of the Optojump Infrared Photocell System in Lower Limb Peak Power Assessment: Comparative Analysis with the Wingate Anaerobic Test and Sprint Performance
Khemiri, Aymen; Negra, Yassine; Ceylan, Halil İbrahim; Hajri, Manel; Njah, Abdelmonom; Hachana, Younes; Yıldız, Mevlüt; Bayrakdaroğlu, Serdar; Muntean, Raul Ioan; Attia, Ahmed
Aim: This study analyzed the concurrent validity of the Optojump infrared photocell system for estimating lower limb peak power by comparing it with the 15 s Wingate anaerobic test (WAnT) and examining relationships with sprint performance indicators. Methods: Twelve physically active university students (ten males, two females; age: 23.39 ± 1.47 years; body mass: 73.08 ± 9.19 kg; height: 173.67 ± 6.97 cm; BMI: 24.17 ± 1.48 kg·m−2) completed a cross-sectional validation protocol. Participants performed WAnT on a calibrated Monark ergometer (7.5% body weight for males, 5.5% for females), 30 s continuous jump tests using the Optojump system (Microgate, Italy), and 30 m sprint assessments with 10 m and 20 m split times. Peak power was expressed in absolute (W), relative (W·kg−1), and allometric (W·kg−0.67) terms. Results: Thirty-second continuous jump testing produced systematically higher peak power values across all metrics (p < 0.001). Mean differences indicated large effect sizes: relative power (Cohen’s d = 0.99; 18.263 ± 4.243 vs. 10.99 ± 1.58 W·kg−1), absolute power (d = 0.86; 1381.71 ± 393.44 vs. 807.28 ± 175.45 W), and allometric power (d = 0.79). Strong correlations emerged between protocols, with absolute power showing the strongest association (r = 0.842, p < 0.001). Linear regression analysis revealed that 30 s continuous jump-derived measurements explained 71% of the variance in Wingate outcomes (R2 = 0.710, p < 0.001). Sprint performance showed equivalent predictive capacity for both tests (Wingate: R2 = 0.66; 30 s continuous jump: R2 = 0.67). Conclusions: The Optojump infrared photocell system provides a valid and practical alternative to laboratory-based ergometry for assessing lower limb anaerobic power. While it systematically overestimates absolute values compared with the Wingate anaerobic test, its strong concurrent validity (r > 0.80), large effect sizes, and equivalent predictive ability for sprint performance (R2 = 0.66–0.71) confirm its reliability as a field-based assessment tool. These findings underscore the importance of sport-specific, weight-bearing assessment technologies in modern sports biomechanics, providing coaches, practitioners, and clinicians with a feasible method for monitoring performance, talent identification, and training optimization. The results further suggest that Optojump-based protocols can bridge the gap between laboratory precision and ecological validity, supporting both athletic performance enhancement and injury prevention strategies.
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- MakaleYayıncıda açık erişim2025Scopus SJRQ2The effect of health literacy, psychological resilience, and internet addiction levels on the fear of COVID-19 in healthcare professionals
Aydin, Aykut; Aydin Sayilan, Aylin; Kulakac, Nursen
Background: Healthcare professionals are known to make intensive use of the internet to improve their health literacy, preserve their psychological resilience, resolve uncertainties, and lessen their fear of COVID-19. Although several studies have addressed these concepts, we encountered none examining their relationships with one another. Objective: This research set out to determine the effects of health literacy, psychological resilience, and internet addiction levels on the fear of COVID-19 in healthcare professionals. Methods: The sample in this descriptive, cross-sectional, and correlation-seeking research consisted of 456 health workers. The data were collected using an information form and the Health Literacy Scale (HLS), the Brief Resilience Scale (BRS), Young's Internet Addiction Test-Short Form (YIAT-SF), and the Fear of COVID-19 Scale. Results: The mean age of the health professionals enrolled in the research was 40.80 ± 11.39 years (min 22, max 68), 52.4% were women, 87.1% held bachelor's degrees, 86.8% were married, and 5.9% were working as nurses. The participants’ mean scale scores were 54.97 ± 5.62 for the HLS, 26.95 ± 9.57 for YIAT-SF, 20.57 ± 3.62 for the BRS, and 20.33 ± 2.97 for the Fear of COVID-19 Scale. Conclusions: The healthcare professionals in this study exhibited adequate levels of health literacy and psychological resilience, a moderate level of internet addiction, and still experienced fear of COVID-19. Health literacy, internet addiction, and psychological well-being emerged as important factors in the fear of COVID-19.
- MakaleAçık Erişim2025Scopus SJRQ1Effect of basic parameters defining principal soil-structure interaction on seismic control of structures equipped with optimum tuned mass damper
Araz, Onur
One of the most effective systems for reducing dynamic responses of the structures subjected to earthquake excitations is tuned mass dampers (TMDs). In the traditional design theory of TMDs, the structures are assumed to be rigidly connected to the ground. Using this approach, known as the fixed foundation approach, may lead to deterioration of the performance of the TMD in cases where soil-structure interaction (SSI) is significant. Therefore, it is crucial to consider the SSI effects to obtain the optimum parameters of the TMDs. Unlike previous studies, two key parameters (i.e., structure-to-soil stiffness ratio and aspect ratio of the structure) are considered, which define the principal SSI effects on the effectiveness of TMD. For the aspect ratio of the structure, three different values (i.e., λ = 1, 2, and 4) are considered, these values correspond to the squat, ordinary, and slender structures representing traditional buildings, respectively. Four different values (i.e., a0 = 0, 0.5, 1, and 2) are also considered for the structure-soil stiffness ratio. This ratio being equal to 0 corresponds to the fixed foundation approach. This also demonstrates that the structure is constructed on hard rock. The optimum parameters of the TMD are obtained using the Jaya algorithm (JA). The proposed methodology is applied to three different buildings (i.e., 3-story, 6-story, and 12-story), and the optimum parameters of the TMD are verified using a total of 72 ground motions corresponding to NEHRP site classes C, D, and E. Numerical results show that the effectiveness of TMD is significantly affected by the basic parameters that define the principal SSI. In addition, the efficiency of the TMD is significantly related to the characteristics of the ground motions. It has been observed that TMD does not perform adequately in reducing vibrations in low-rise buildings (i.e., λ = 1) constructed on low-stiffness soils (i.e., a0 = 2).
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- Kitap BölümüYalnız künye2025Conclusion
Özsungur, Fahri; Bekar, Fevziye
This edited book offers a comprehensive examination of proactive behavior (PBs) in organizational contexts, emphasizing its critical role in addressing the complexities of modern work environments. Bridging psychological, sociological, and managerial perspectives, the book explores how emotions, leadership styles, and identity factors influence proactive engagement. It critically assesses both the benefits and risks of proactivity, including its impact on mental health, conflict resolution, and innovation. Special attention is given to marginalized groups—such as women, immigrants, and LGBTQ+ individuals—highlighting the systemic challenges they face and the need for inclusive, equity-driven approaches to fostering proactive behavior. The book also connects proactive practices to broader societal concerns, including sustainability and ethical governance. By integrating diverse viewpoints and highlighting underexplored dimensions, this book advances the understanding of proactive behavior as a transformative force within and beyond organizational life.
- MakaleYalnız künye2008Scopus SJRQ1Magma interaction processes inferred from Fe-Ti oxide compositions in the Dölek and Sariçiçek plutons, Eastern Turkey
Karsli, Orhan; Aydin, Faruk; Uysal, Ibrahim; Sadiklar, M. Burhan
Magnetite-ulvöspinel and ilmenite-hematite solid solution intergrowths from the high-K calc-alkaline Dölek and Sarιçiçek plutons, Eastern Turkey, were investigated using microprobe analyses. Compositions of twenty-eight samples from the host rocks and their enclaves' in the plutons were used to estimate the oxygen fugacity and temperature. The ilmenite and ulvöspinel component exsolves out along certain preferred crystallographic planes in the titanomagnetite of the host rocks, while they are always absent in those of the mafic-microgranular enclaves. The titanomagnetite and ilmenite show variations as Mt98-70Usp02-30 and Ilm99-65Hm01-35 in composition, respectively. Estimations of oxygen fugacity and temperature using the titanomagnetite-ilmenite thermometry/oxygen barometry range from log/O2 of -15.30 to -20.48 in host rocks, log/O2 of -15.39 to -20.80 in the mafic microgranular enclaves and 617±6 to 758±23 °C in host rocks, 622±6 to 735±24 °C in the mafic microgranular enclaves, possibly indicating crystallisation temperature. Applying magnetite-ilmenite thermometry/ oxygen barometry to the granitoid rocks also involves microprobe analyses of ilmenite lamellae in titanomagnetite and this method yielded mean temperatures of 679±18 °C. The specific forms and chemical properties of Fe-Ti oxides, and similarities in crystallization temperature and oxygen fugacity of the host rocks and the mafic microgranular enclaves (MME) obtained from the Fe-Ti oxide pairs imply that thermal equilibrium probably occurred between two contrasted magmas, which mixed invarious proportion so that possibly a felsic and a more mafic magma interaction occurred in a convectively dynamic magma chamber during crystallization of the plutons. Probably, underplating may be responsible for genesis of the hybrid plutons. Thus, for mixing of coeval magmas derived from a lithospheric upper mantle (mafic end-member) and lower crust (felsic end-member), a thermal anomaly should be supplied. Upwelling of hot asthenospheric material result in thermal perturbation and melting of lithospheric mantle. Intrusion of hot lithospheric mantle-derived mafic magma then induced lower crustal melting, producing felsic melt. Mixing of the lower crust-derived melt and lithospheric mantle-derived magma formed the hybrid pluton. This process requires a post-collisional extensional tectonic setting during the Eocene in the Eastern Pontides.
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- MakaleYalnız künye2007Traditional Turkish masonry monumental structures and their Earthquake response
Doğangün, Adem; Sezen, Halil; Tuluk, Ö. İskender; Livaoğlu, Ramazan; Acar, Ramazan
Many historical and new masonry minarets were damaged or collapsed during the 1999 earthquakes in Kocaeli and Duzce, Turkey. These and other recent earthquakes not only caused loss of property but also loss of many lives. The structural failures and resulting casualties have led to discussion and investigation of potential reasons for poor seismic performance of masonry minarets. The primary goal of this study is to review the construction practices for historical and new masonry minarets in Turkey and to discuss the seismic damage observed in those structures. The architectural and structural properties of contemporary and historical Ottoman minarets and their components are presented. For example, a very old special technique for reinforcing and linking adjacent stone blocks with iron pieces in the vertical and horizontal directions is discussed. The structural damage examples are used to better understand the reasons for the observed failure mechanisms. It is concluded that the transition region between the square minaret boot and cylindrical body was most vulnerable to damage, and the iron clamps used in historical minarets effectively prevented structural damage.
AtıfScopus43OpenAlex61İncele
- MakaleYalnız künye2007Scopus SJRQ1Geochemical and Sr-Nd-Pb isotopic compositions of the Eocene Dölek and Sariçiçek Plutons, Eastern Turkey: Implications for magma interaction in the genesis of high-K calc-alkaline granitoids in a post-collision extensional setting
Karsli, Orhan; Chen, Bin; Aydin, Faruk; Şen, Cüneyt
The major and trace elements and Sr-Nd-Pb isotopes of the host rocks and the mafic microgranular enclaves (MME) gathered from the Dölek and Sariçiçek plutons, Eastern Turkey, were studied to understand the underlying petrogenesis and geodynamic setting. The plutons were emplaced at ∼ 43 Ma at shallow depths (∼ 5 to 9 km) as estimated from Al-in hornblende geobarometry. The host rocks consist of a variety of rock types ranging from diorite to granite (SiO2 = 56.98-72.67 wt.%; Mg# = 36.8-50.0) populated by MMEs of gabbroic diorite to monzodiorite in composition (SiO2 = 53.21-60.94 wt.%; Mg# = 44.4-53.5). All the rocks show a high-K calc-alkaline differentiation trend. Chondrite-normalized REE patterns are moderately fractionated and relatively flat [(La/Yb)N = 5.11 to 8.51]. They display small negative Eu anomalies (Eu/Eu* = 0.62 to 0.88), with enrichment of LILE and depletion of HFSE. Initial Nd-Sr isotopic compositions for the host rocks are εNd(43 Ma) = - 0.6 to 0.8 and mostly ISr = 0.70482-0.70548. The Nd model ages (TDM) vary from 0.84 to 0.99 Ga. The Pb isotopic ratios are (206Pb/204Pb) = 18.60-18.65, (207Pb/204Pb) = 15.61-15.66 and (208Pb/204Pb) = 38.69-38.85. Compared with the host rocks, the MMEs are relatively homogeneous in isotopic composition, with ISr ranging from 0.70485 to 0.70517, εNd(43 Ma) - 0.1 to 0.8 and with Pb isotopic ratios of (206Pb/204Pb) = 18.58-18.64, (207Pb/204Pb) = 15.60-15.66 and (208Pb/204Pb) = 38.64-38.77. The MMEs have TDM ranging from 0.86 to 1.36 Ga. The geochemical and isotopic similarities between the MMEs and their host rocks indicate that the enclaves are of mixed origin and are most probably formed by the interaction between the lower crust- and mantle-derived magmas. All the geochemical data, in conjunction with the geodynamic evidence, suggest that a basic magma derived from an enriched subcontinental lithospheric mantle, probably triggered by the upwelling of the asthenophere, and interacted with a crustal melt that originated from the dehydration melting of the mafic lower crust at deep crustal levels. Modeling based on the Sr-Nd isotope data indicates that ∼ 77-83% of the subcontinental lithospheric mantle involved in the genesis. Consequently, the interaction process played an important role in the genesis of the hybrid granitoid bodies, which subsequently underwent a fractional crystallization process along with minor amounts of crustal assimilation, en route to the upper crustal levels generating a wide variety of rock types ranging from diorite to granite in an extensional regime.
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