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- MakaleYalnız künye2026Scopus SJRQ2Drying Shrinkage and Microstructural Properties of Geopolymers Including Steel and Iron Particles
Gulmez, Nihan; Kockal, Niyazi Ugur
Geopolymer mortars show significantly higher shrinkage than normal Portland cement mortars. So, one of the most important disadvantages of these promising alternative binding materials for their wider applications is the cracking occurring by shrinkage. Different inserts and fibers are used in fresh mixtures in order to control drying shrinkage cracks and to provide mechanical capacity. The aim of this study is to investigate the effectiveness of using both metal particles (iron particles) and metallic fibers (steel particles) in geopolymer composites to reduce drying shrinkage. In addition, microstructural properties of composites were determined by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses and causes of shrinkage were investigated in detail. Mixtures containing 20% silica fume have 38.4% lower drying shrinkage than slag-based mixtures. In slag-based composites, decreases in drying shrinkage were found as 18.8% and 49.1% when adding 10% iron particles or 10% steel particles compared to metal-free composites.
- MakaleYalnız künye2025Scopus SJRQ2Annealing temperatures effects on structural and optical properties of CdO thin films
Aydin, Handan; Odak, Mehmet
In this study, the structural and optical properties of CdO thin films subjected to heat treatment at different temperatures were investigated. CdO films were deposited on glass substrates by thermal evaporation. X-ray diffraction technique (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and atomic force microscopy (AFM) measurements were taken to investigate the crystal structure and surface morphology of the prepared films UV-vis spectrometer was utilized to measure the optical properties. As a result of XRD measurements, it was observed that the CdO thin film without and with heat treatment has a cubic crystal structure. The increase in the sharpness of x-ray peaks in CdO thin films with heat treatment means an increase in crystallization, and the calculated crystal sizes showed that the crystal size generally tends to increase with a rise in the applied annealing temperature. As can be seen from the SEM images, it was observed that the small grains on the surface were replaced by large grains as a result of the merger of small grains with each other with rising annealing temperature. The optical band gap Eg, which changes with heat treatment, was calculated to be between 2.45 and 2.27 eV. It was concluded that heat treatment improves the conductivity of CdO thin films by reducing the Eg value.
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İncele - MakaleAçık Erişim2025Scopus SJRQ3Sexually transmitted diseases-related knowledge levels of midwifery students studying at two different universities: A comparative study
Yeşiltepe, Akgün; Ulucan, Mihriban; Akan, Ayşenur; Can, Hafize Öztürk
This study aimed to compare the knowledge levels of midwifery students from two universities in eastern and western Turkey regarding sexually transmitted diseases (STDs). A descriptive, comparative study was conducted with midwifery students from both regions.The average score on the STD Knowledge Test was 14.49±3.83. Students from the western university scored 14.63±3.60, while those from the eastern university scored 13.98±4.58. Among western university students, knowledge scores were significantly associated with factors such as year of study, place of residence, and prior sexual health education. For eastern university students, significant factors included age, year of study, social security status, and university-based sexual health education (p<0.05). It is recommended that educational programs be strengthened to enhance students' knowledge and improve access to accurate, reliable information. African Journal of Reproductive Health © 2025.; L'étude visait à comparer les niveaux de connaissance des étudiants sages-femmes de deux universités situées l'est et à l'ouest de la Turquie sur les maladies sexuellement transmissibles. Cette étude descriptive et comparative a été menée auprès d'étudiants des départements de sages-femmes de deux universités différentes situées dans les régions de l'est et de l'ouest de la Turquie. Le score moyen obtenu par le test de connaissances sur les maladies sexuellement transmissibles était de 14,49±3,83. Alors que le score moyen obtenu par « les participants fréquentant l'université de l'ouest de la Turquie était de 14.63±3.60, le score moyen obtenu par » les participants fréquentant l'université de l'est de la Turquie était de 13.98±4.58. Alors qu'il y avait une relation statistiquement significative entre les scores moyens obtenus au test de connaissance des maladies sexuellement transmissibles par les étudiants de l'université de l'ouest et les variables telles que l'année scolaire, le lieu de résidence, l'éducation à la santé sexuelle au lycée, l'éducation à la santé sexuelle à l'université, et la connaissance des maladies sexuellement transmissibles, il y avait une relation statistiquement significative entre les scores moyens obtenus à la même échelle par les étudiants de l'université de l'est et les variables telles que l'âge, l'année scolaire, la sécurité sociale, l'éducation à la santé sexuelle à l'université (p˂0,05). Le niveau de connaissance des étudiants sur les maladies sexuellement transmissibles est insuffisant; il est donc recommandé que les étudiants participent à des activités éducatives pour améliorer leur niveau de connaissance sur les maladies sexuellement transmissibles et pour leur permettre d'accéder à des sources précises et fiables.
- MakaleAçık Erişim2026Scopus SJRQ1Examining the effect of authentic leadership and contextual performance on work engagement among employees working in sports organizations
İnce, Uğur; Özcan, Büşra; Siyahtaş, Anıl; Erdoğan, Ramazan
Background – This study examines the relationship between authentic leadership and employees’ contextual performance and investigates its association with work engagement. Specifically, the aim was to explore how authentic leadership practices are associated with employee motivation and job performance in the sports sector. Methods – The study employed a quantitative research method using measures of authentic leadership, work engagement, and contextual performance. Data were collected through surveys administered to participants, and various statistical analyses were conducted. A mediation analysis was conducted to examine whether work engagement mediates the relationship between authentic leadership and contextual performance. Results – The analysis showed that authentic leadership is positively associated with work engagement (β = 0.516; p < 0.001). Work engagement is also positively associated with contextual performance (β = 0.393; p < 0.001). Mediation analysis suggested that authentic leadership is indirectly associated with contextual performance through work engagement [indirect effect β = 0.205; 95% CI (0.152, 0.259); p < 0.001], while the direct association between authentic leadership and contextual performance remained significant (β = 0.311; p < 0.001). Conclusion – The study’s results indicate that authentic leadership is positively associated with contextual performance via higher employee engagement in the sports sector. The trusting environment and supportive communication provided by authentic leaders are associated with higher employee motivation and linked to better performance outcomes. The findings suggest that sports managers may benefit from cultivating authentic leadership qualities, which are likely to be associated with greater organizational effectiveness.
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İncele - MakaleAçık Erişim2026Scopus SJRQ3Effect of mechanical activation on lithium and alkali cation release from dolomitic clay wastes of boron processing plant
Boylu, Feridun; Teker, Gülsen Obuz; Angur, Gafure Ersever; Ozdemir, Orhan; Çelik, Mehmet Sabri
With the significant increase in lithium demand and production, alternative resources such as lithium-bearing clays have increasingly attracted attention and have been considered as a potential source. In addition to conventional Li recovery methods such as acid treatment and roasting, more economical and environmentally friendly techniques such as mechanical activation followed by water leaching are also being considered. In Türkiye, wastes from boron processing plants, containing approximately 900 ppm of lithium and mainly of dolomitic clays and unrecovered boron minerals (~10-13% of waste), are considered as a potential lithium source. However, due to high dolomite and boron mineral contents, the waste material may release significant amounts of alkaline earth ions such as Na+, K+, Mg2+, Ca2+, and B2O3 during leaching, which may interfere with lithium extraction from the solution. In this study, the leaching behavior of lithium, alkali ions, and other possible elements (e.g., B2O3, Fe3+, and Al3+) from both raw clay waste and mechanically activated forms of this waste material was investigated in detail. The results showed that water leaching without sodium salt of activated waste samples achieves about 44.7–57.7% lithium recovery, yielding high lithium concentrations (80–115 ppm), low levels of alkali ions (4430 ppm Na+, 114 ppm K+, 20 ppm Ca2+, and 7 ppm Mg2+), and almost no detectable Fe3+ (<0.2 ppm) or Al3+ (0.07 ppm) ions. On the other hand, a single problem was encountered where 0.95 % of B2O3 concentrations did not decrease in water leaching at even room temperature.
- MakaleAçık Erişim2026Scopus SJRQ4Oxidative Stress Response to Zinc Oxide, Copper Oxide and Iron (III) Oxide in Gammarus pulex; [Gammarus pulex'te Çinko Oksit, Bakır Oksit ve Demir (III) Oksit'e Karşı Oksidatif Stres Tepkisi]
Aydin, Ayşe Nur; Çiçek Çi̇Men, Işıl Canan; Serdar, Osman
Nanoparticles (NPs) are increasingly used across various fields of science and technology, including food science from crop harvesting to final food consumption. With their widespread application in daily life, the environmental effects of nanoparticles have become an important area of academic investigation. In this study, Gammarus pulex species was selected as research material/bioindicator species to investigate the effects of zinc oxide (ZnO), copper oxide (CuO), and iron(III) oxide (Fe2O3) on aquatic life. To conduct the experiments, separate setups were established for each of the nanoparticles (ZnO, CuO, and α-Fe2O3). Following ten organisms for each concentration group (10, 20, and 40 ppm) with corresponding control groups, exposures were performed for 24 and 96 hours. Samples were collected at both time points and biochemical analyses were conducted using homogenization procedures. The results were evaluated statistically. According to the findings, SOD activity increased significantly after exposure to ZnO, CuO, and Fe2O3. CAT activity did not show any change under ZnO NP exposure, whereas a decrease was observed under CuO and Fe2O3 NP exposures. However, a significant increase in TBARS levels and a significant increase in GSH levels were observed following nanoparticle exposure. Based on the study data, exposure to ZnO, CuO, and Fe2O3 appears to induce oxidative stress in G. pulex.
- MakaleAçık Erişim2026Scopus SJRQ2Exploring Health Literacy, Anxiety, and Perception Among Nursing and Allied Health Students in Turkey: A Cross-Sectional Study
Yeşiltepe, Akgün; Daşbilek, Ferhat; Ayhan, Mehmet Osman
Background: Health literacy, anxiety, and perception directly affect healthcare students' readiness for professional roles. Assessing these factors is crucial to enhance both their well-being and patient care quality. This study examined health literacy, health anxiety, and health perception among Health Sciences students and their links to socio-demographic factors. Methods: A cross-sectional and descriptive design was used in accordance with the STROBE guidelines. The sample, consisting of 258 students from Munzur University Faculty of Health Sciences, was selected using stratified and simple random sampling methods. Data were collected using a Descriptive Information Form, the Health Literacy Scale, the Health Anxiety Inventory, and the Health Perception Scale. Descriptive statistics, Mann−Whitney U, Kruskal−Wallis tests with Bonferroni correction, and Spearman's correlation analysis were conducted using SPSS 26 and JASP 0.19. Results: Students demonstrated inadequate health literacy (17.75 ± 11.37) and moderate health perception (43.43 ± 6.25); the mean health anxiety score was 18.78 ± 6.14. A weak but statistically significant positive correlation was found between health literacy and health anxiety (r = 0.225, p < 0.05) and between health perception and health anxiety (r = 0.215, p < 0.05); however, no significant correlation was observed between health literacy and health perception (r = 0.090, p > 0.05). Health perception revealed statistically significant differences according to maternal education level, place of residence, and frequency of reading health-related research. Health literacy significantly differed by academic department, year of study, perceived health status, and perceived usefulness of online health information. Health anxiety varied significantly by the presence of chronic illness, chronic illness status, perceived health status, medication use, and alcohol/tobacco consumption. Conclusion: The findings highlight the complex interplay between cognitive (health literacy), emotional (health anxiety), and perceptual (health perception) dimensions of student health. Promoting digital health literacy and providing counselling services may help reduce health anxiety and enhance self-awareness among health sciences students.
- MakaleYalnız künye2025Scopus SJRQ1The Extraction of Rare-Earth Elements (REEs) from Spent Nickel–Metal Hydride (Ni–MH) Batteries by Bifunctional Ionic Liquids (Bif-ILs): Process Optimization and Kinetics Modeling
Erust, Ceren
The cathode material of nickel–metal hydride (Ni–MH) batteries includes nickel, cobalt, and rare-earth elements (REEs) such as La, Ce, Nd, and Pr, which are among the critical raw materials (CRMs). Ionic liquids as the environmentally friendly approaches are proposed by various investigations for the extraction of critical metals from spent Ni–MH batteries. In this study, three different Bifunctional Ionic Liquids (Bif-ILs) were designed for comparative studies, namely Aliquat 336–Cyanex 272 (AL–CY), Aliquat 336–PC88A (AL–PC), and Aliquat 336–D2EHPA (AL–D2). The extraction results indicated that temperature has a direct effect on the extraction of critical metals in the presence of all Bif-ILs. Among three types of Bif-ILs, AL–D2 has an optimal extraction power (La: 98.8%, Ce: 94.2%, Nd: 99.2%, and Pr: 98.4%) after precipitation of 99.99% of Ni and Co. Furthermore, kinetics modeling is used for reaction mechanisms investigation. Results indicated that the mixed controlled model by shrinking core model (diffusion controlled and chemical reaction controlled) was the best model fitted to all data (coefficient of determination (R2) > 0.90). according to the Arrhenius equation, activation energies for all REEs in the presence of all Bif-ILs are between 13 and 42 kJ/mol that reflects a mixed controlled reaction.
AtıfScopus2OpenAlex2İncele - MakaleAçık Erişim2025Scopus SJRQ1Deep learning and optimization-based feature selection for fetal health classification using CTG data
Kaya, Turgay; Kaya, Duygu; Atar, Fatmanur
This study introduces a DL and metaheuristic optimization-based framework for fetal health assessment using cardiotocography (CTG) signals to mitigate maternal and neonatal mortality. One-dimensional CTG signals were transformed into 2D representations, and deep feature extraction was performed using AlexNet. Feature vectors FC6, FC7, and their combination were subjected to optimization via Whale Optimization Algorithm (WOA + DL) and War Strategy Optimization (WSO + DL), utilizing updated fitness functions tailored for feature selection. Experimental results with SVM classifiers demonstrated superior performance with FC6 (89.98 %) and WSO + DL (90.17 %). FC6 exhibited strong discriminative capacity, while FC7 contained semantically richer features. The concatenated FC6 + FC7 vector increased feature diversity. WSO + DL achieved optimal balance across classification accuracy, feature subset size, convergence rate, and overall performance metrics. The integration of DL and metaheuristic algorithms effectively isolated informative feature subsets, improving training efficiency, minimizing redundant/noisy data, reducing overfitting risk, and enhancing classification accuracy. Optimization method selection proved critical to overall model performance.
AtıfScopus6WoS1OpenAlex6İncele - MakaleYayıncıda açık erişim2026Scopus SJRQ3Interfacial Polarization in PS/Sm2O3 Nanocomposite Films for Low-Loss Frequency-Dependent Dielectric Application
Güner, Melek; Özkan, Betül Çiçek; Gürgenç, Ezgi; Macit, Cevher Kürşat; Aslan, Naim; Gurgenc, Turan
Rare-earth oxide nanoparticles offer a strategy to tune dielectric films via interfacial polarization while maintaining low-loss insulating behavior. Here, polystyrene/samarium oxide (PS/Sm2O3) nanocomposite films containing 0, 1, 3, 5, and 10 wt.% Sm2O3 were fabricated by solvent casting and evaluated as a low-loss dielectric for frequency-sensitive electronic applications. FTIR, XRD, SEM/EDX, and XPS confirmed successful Sm2O3 incorporation, preservation of the PS structure, formation of PS/Sm2O3 interfacial regions, and Sm3+/Sm–O species. XRD revealed amorphous PS with increasingly intense crystalline Sm2O3 reflections, whereas SEM/EDX showed relatively uniform filler distribution at low and moderate loadings and partial agglomeration at 10 wt.%. Dielectric spectroscopy at room temperature from 1 kHz to 1 MHz showed a frequency-dependent response governed by interfacial polarization and limited charge transport. At 1 kHz, the dielectric constant increased from 8.67241 ± 0.00280 for pure PS to 10.13061 ± 0.00641 for PS-10, while the loss tangent remained low (∼ 0.068). The dielectric loss increased moderately from 0.59535 ± 0.00236–0.69194 ± 0.00710, and AC conductivity rose from (3.31202 ± 0.01314) × 10−10 to (3.84935 ± 0.03948) × 10−10 S cm−1. These results indicate interface-controlled dielectric enhancement without conductive percolation, highlighting PS/Sm2O3 films for capacitor dielectric layers, insulating films, flexible electronics, and frequency-sensitive dielectric technologies.
- MakaleYalnız künye2025Scopus SJRQ2Eu2O3-driven tailoring strategies on Al6061-Alloy for nuclear applications: A comprehensive study on structural, physical, and radiation transmission properties
Basgoz, Oykum; Guler, Seval Hale; Guler, Omer; ALMisned, Ghada; Baykal, Duygu Sen; Kilic, G.; Tekin, H.O.
In this study, Al6061–Eu2O3 composites were fabricated via mechanical alloying and systematically characterized using X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy to evaluate structural and compositional features. The incorporation of Eu2O3 in varying weight percentages (1–20 wt%) was confirmed by XRD, revealing phase retention and crystallite refinement, while SEM–EDS analyses indicated uniform elemental distribution at low doping and localized clustering at higher reinforcement levels. Radiation shielding properties were comprehensively assessed through mass and linear attenuation coefficients, half value layer, effective atomic number, fast neutron removal cross section, buildup factors, and photon transmission factors. The results demonstrated a strong correlation between increasing Eu2O3 content and improved shielding performance. The E20 composite exhibited a mass attenuation coefficient of 22.33 cm2/g at 0.015 MeV, over threefold higher than the base alloy, and fast neutron removal cross section improved by 22.5 % compared to Al6061 alone. Additionally, EBF and EABF values decreased significantly, confirming reduced secondary photon build-up. These findings validate the effectiveness of Eu2O3 as a reinforcement phase for tailoring Al6061 for multifunctional applications, particularly in nuclear, aerospace, and radiological environments requiring lightweight materials with superior gamma and neutron attenuation.
AtıfScopus1OpenAlex1İncele - MakaleYayıncıda açık erişim2026Scopus SJRQ1Tailoring of Dy2O3-B4C hybrid-reinforcements in Fe-Co-Ni-Cr-W High-Entropy Alloy (HEA) matrix for correlating structural, mechanical, and experimental gamma-ray transmission behaviour
Özkul, İskender; Güler, Ömer; Camgoz, Berkay; ALMisned, Ghada; Yaprak, Gunseli; Tekin, H.O.; Durmus, Hasan
This study investigates the structural, mechanical, and experimental gamma-ray attenuation properties of Fe-Co-Ni-Cr-W high-entropy alloy (HEA) composites reinforced with varying concentrations of Dy2O3 and B4C. A series of samples (S0-S4) was synthesized via vacuum arc melting to evaluate the synergistic effects of rare-earth oxide and carbide additions on a stable multi-component matrix. Thermodynamic assessments confirmed that the base alloy aligns with solid-solution formation criteria (1.61R configurational entropy, Ω = 10.33), which was experimentally validated by XRD patterns revealing a consistent FCC crystal structure across all compositions. SEM-EDS mapping further verified the successful integration of reinforcements as discrete secondary phases within the HEA matrix. Mechanical characterization showed that ceramic incorporation significantly enhances the hardness of the monolithic HEA, with the hybrid-reinforced S3 sample achieving a peak value of 628 HV. This improvement is attributed to the combined effects of oxide dispersion strengthening and microstructural refinement induced by B4C. Experimental gamma-ray transmission tests, conducted using a high-purity germanium (HPGe) detector in the 276-383 keV energy range, demonstrated that the S3 configuration provides the most efficient shielding performance, characterized by the lowest transmission factors. Interestingly, the results suggest that beyond an optimal threshold, increased reinforcement loading, as seen in S4 sample, may lead to minor performance trade-offs due to phase distribution dynamics. The findings highlight that the development of multifunctional HEA-based shields requires a delicate balance between reinforcement volume fraction and microstructural homogeneity to maximize both structural and shielding efficiency.
AtıfOpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ3Neuro-linguistic programming for postoperative pain management: A randomized controlled trial
Dal, Nursel Alp; Beydağ, Kerime D.; Doğan, Aysel
Effective control of pain after cesarean delivery is essential, as poorly managed postoperative pain is a common complication that can impair maternal recovery and early infant care. This prospective, randomized, single-blind controlled trial, conducted in the postpartum unit of Kocaeli University Hospital, Kocaeli, Türkiye, between March 2021 and June 2022, compared the effect of a single neuro-linguistic programming (NLP) session added to standard postoperative care against standard care alone. Seventy-six consenting women were randomized in equal numbers to the intervention (standard care plus NLP) or control (standard care only) group. The primary outcome was pain intensity, measured with the Visual Analogue Scale (VAS) before and after the intervention period. Mean follow-up pain scores were significantly lower in the intervention group (2.37±1.792) than in the control group (6.68±2.068; p<0.001), while baseline pain scores and maternal demographic and obstetric characteristics did not differ significantly between groups. Adding a single NLP session to standard postoperative care effectively reduced pain after cesarean delivery, supporting its use as a non-pharmacological adjunct in postoperative nursing and midwifery practice. African Journal of Reproductive Health © 2026.; Une prise en charge efficace de la douleur après une césarienne est essentielle, car une douleur postopératoire mal gérée constitue une complication fréquente susceptible de nuire au rétablissement de la mère et aux premiers soins prodigués au nourrisson. Cet essai prospectif, randomisé, contrôlé en simple aveugle, mené dans l’unité post-partum de l’hôpital universitaire de Kocaeli, à Kocaeli, en Turquie, entre mars 2021 et juin 2022, a comparé l’effet d’une seule séance de programmation neurolinguistique (PNL) ajoutée aux soins postopératoires standard à celui des soins standard seuls. Soixante-seize femmes ayant donné leur consentement ont été randomisées en nombre égal dans le groupe d’intervention (soins standard plus PNL) ou dans le groupe témoin (soins standard uniquement). Le critère d’évaluation principal était l’intensité de la douleur, mesurée à l’aide de l’échelle visuelle analogique (EVA) avant et après la période d’intervention. Les scores moyens de douleur observés lors du suivi étaient significativement plus faibles dans le groupe d’intervention (2,37 ± 1,792) que dans le groupe témoin (6,68 ± 2,068 ; p < 0,001), tandis que les scores de douleur initiaux ainsi que les caractéristiques démographiques et obstétricales des mères ne présentaient pas de différence significative entre les groupes. L’ajout d’une seule séance de PNL aux soins postopératoires standard a permis de réduire efficacement la douleur après une césarienne, ce qui plaide en faveur de son utilisation comme complément non pharmacologique dans la pratique infirmière et obstétricale postopératoire.
- MakaleAçık Erişim2025Scopus SJRQ1MobileNet- and attention-based MLP-Mixer architecture for geographical-region recognition of a marine fish (Perciformes: Carangidae) using otolith images
Dürrani, Ömerhan; İşgüzar, Seda; İmak, Andaç; Ateşşahin, Tuncay; Cömert, Zafer; Dürrani, Syeda Zahra; Türkoğlu, Muammer
Fishery management is crucial to sustain marine ecosystems by preventing overfishing and ensuring a fair distribution of fishing quotas. Accurately identifying the geographical origins of fish stocks is a key challenge in region-specific management strategies. Otoliths, calcified structures found in the heads of all fish species (except sharks and rays), provide insights into the life history and geographical origins of these fish. Traditional otolith analysis is time-consuming and error-prone because of manual inspection. Our study presents a novel approach using deep learning and computer vision to automate the geographical recognition of fish using otolith images. We propose a model that integrates MobileNet, which is known for its efficiency, with an advanced Mlp-Mixer that incorporates an attention mechanism to extract enhanced features. When tested on a diverse dataset of otolith images from five regions, the proposed model achieved a remarkable 96% accuracy, significantly outperforming traditional methods. This high accuracy demonstrates the potential to revolutionise fishery management by providing a fast, reliable, and automated solution for geographical region identification. In conclusion, the proposed method demonstrates the transformative potential of combining MobileNet and an attention-based Mlp-Mixer for automated fish geographic recognition using otolith images. This innovative method addresses the limitations of traditional manual inspection and paves the way for more effective and sustainable fishery management practices.
AtıfScopus4OpenAlex4İncele - MakaleYalnız künye2025Scopus SJRQ1Evaluation of TiO2/ZnO/SnO2 multilayer thin films on Si(100) as triboelectric friction layer
Yüzüak, G. Durak; Yüzüak, E.
This study presents a novel multilayer-semiconductor triboelectric nanogenerator (MLSC-TENG) that enhances charge transfer and initial charge density to overcome the limitations of conventional TENGs by multilayer thin films composed of TiO2, ZnO, and SnO2. The device operates through contact electrification and electrostatic induction, featuring two distinct electrodes. The active negative layer is deposited on Si substrates with an Ag seed layer using magnetron sputtering, employing a PET/ITO counter-electrode. The system attains a maximum power density of 400 mW/m2 with a 100 MΩ load, a short-circuit current of 20 μA at 10 Hz, and an open-circuit voltage of ±55 V. Additionally, it powers 156 LEDs and exhibits an energy storage capacity of 16.9 μJ at 52 μF, highlighting its applicability for wearable electronics. This scalable and cost-effective approach highlights the significant role of semiconductor (SC) band structures in enhancing TENG performance and presents a viable pathway for sustainable energy harvesting. The demonstrated strategy has the potential to meaningfully influence the application of TENGs in energy harvesting systems, providing a cost-effective solution for powering wearable electronics. The study facilitates progress in sustainable energy solutions for future wearable technologies by tackling critical issues in energy conversion efficiency.
AtıfScopus2WoS3OpenAlex3İncele - MakaleAçık Erişim2026Scopus SJRQ1Loneliness as a predictor of quality of life in older adults receiving primary health care in Türkiye: a cross-sectional study
Atila, Dinçer; Yeşiltepe, Akgün; Çal, Ayşe
Background: Loneliness and social isolation among older adults is a growing concern in many societies, as the aging population continues to increase. The aim of the study is to examine the relationship between loneliness and quality of life in individuals aged 65 and over who apply to primary health care institutions. Methods: This descriptive-correlational study was conducted face-to-face with 216 individuals aged 65 and over. The socio-demographic form and the Loneliness Scale for Elderly and Quality of Life Scale were used as data collection tools in the study. JASP 0.19, SPSS 26 analysis programs were used to perform t test, One Way ANOVA Bonferrroni test, Pearson correlation, and regression analysis. Results: According to Pearson correlation analysis, strong negative relationships were found between quality of life and loneliness in the elderly. As quality of life increased, levels of loneliness, social loneliness, and emotional loneliness decreased (r = −0.854, r = −0.737, r = −0.717; p <0.001). While there was a strong positive relationship between the loneliness scale for elderly and the social loneliness sub-dimension (r = 0.867, p < 0.001), there was also a positive relationship between the loneliness scale for elderly and the emotional loneliness sub-dimension (r = 0.835, p < 0.001). A statistically significant difference was found between chronic disease, educational status, income status, marital status, and both loneliness and quality of life. Conclusion: Loneliness is an important predictor of quality of life among older adults. Both social and emotional loneliness are negatively associated with quality of life, indicating that higher levels of loneliness are linked to lower quality of life in this population.
- MakaleAçık Erişim2026Scopus SJRQ1Comparative Study of Enzymatic and Oxidative Polymerization of a Benzothiazole-Based Schiff Base and Its Antibacterial Properties
Kaya, İsmet; Solmaz, Adnan; Abuawad, Mohammed Majed Shible
In this study, the Schiff base 1-(((6-nitrobenzo[d]thiazol-2-yl) imino)methyl)naphthalen-2-ol (NBTIMN) was synthesized and subsequently polymerized by two different methods. Oxidative polymerization in the presence of organic (o-(NBTIMN)-O) and aqueous alkaline media (o-(NBTIMN)-A) was one of the techniques. The other was enzyme-catalyzed oxidative polymerization (o-(NBTIMN)-E), which was conducted at room temperature with hydrogen peroxide and the enzyme horse radish peroxidase (HRP). The structures of the obtained oligomers were characterized using FT-IR, 1H-13C-NMR, UV–Vis, CV, and GPC analyses, and their electrochemical and optical band gaps were determined as 2.68, 2.66, and 2.49 eV, and 3.08, 2.90, and 3.07 eV for o-(NBTIMN)-O, o-(NBTIMN)-A, and o-(NBTIMN)-E, respectively. Thermal analyses demonstrated that the o-(NBTIMN)-O and o-(NBTIMN)-A derivatives exhibited enhanced thermal stability, characterized by higher decomposition temperatures and LOI values. SEM analyses revealed distinct differences in surface morphologies depending on the polymerization conditions. Antibacterial assays showed that o-(NBTIMN)-O exhibited the strongest broad-spectrum inhibition, whereas NBTIMN displayed pronounced activity against S. aureus. In contrast, o-(NBTIMN)-A and o-(NBTIMN)-E were found to be inactive. These results highlight the critical influence of polymerization conditions on both the physicochemical characteristics and the biological activities of the synthesized structures. Importantly, the comparative design of enzymatic and chemical polymerization demonstrates the potential for environmentally friendly synthesis strategies. The distinct electrochemical and thermal properties suggest applicability in electronics and sensor-related fields, while the pronounced antibacterial activity of o-(NBTIMN)-O holds promise for biomedical and antimicrobial applications.
- MakaleAçık Erişim2026Scopus SJRQ2A New Product: Determination of Shelf Life of Fish Onion Rings at Freezer Temperature
Kuzgun, Nermin Karaton
The enrichment in terms of fish protein of fast food products is becoming increasingly important day by day. The aim of this study was to determine the shelf life of a new product—fish onion rings—under deep-freezing conditions (−18°C). Minced fish meat (180 g) was combined with minced onion (350 g), water (220 mL), corn flour (50 g), wheat flour (180 g), and salt (20 g), and the mixture was blended with a mixer until a homogeneous texture was obtained. Then, the mixture was shaped into onion rings using a dough-shaping tool (manually). The chemical, sensory, and microbiological quality attributes of the fish onion rings were recorded at 30-day intervals. In the samples, deterioration was observed at the end of the 180th day (as chemical, sensory, and microbiological quality). In the fish onion ring group, the TBA (0.07 ± 0.05–3.02 ± 0.97) and peroxide (0.19 ± 0.18–4.40 ± 0.31) values remained similar during storage. In the microbiological analysis of the experimental fish onion rings, the total viable count (TVC) was 2.63 ± 0.15 on Day 0. Furthermore, the samples underwent sensory evaluation for appearance, odor, and taste. It was determined that the most preferred group was the fish-supplemented group.
- MakaleAçık Erişim2025Scopus SJRQ1An efficient 2D hyper chaos and DNA encoding-based s-box generation method using chaotic evolutionary improvement algorithm for nonlinearity
Garipcan, Ali Murat; Aydin, Yılmaz; Özkaynak, Fatih
In this study, an innovative substitution box (s-box) method is proposed, which combines the complexity and unpredictability of chaotic systems with the natural randomness and security features of Deoxyribonucleic Acid (DNA) encoding, in response to the increasing security requirements in the field of modern cryptography. This method, based on the integration of a two-dimensional (2D) hyper-chaotic Vincent map (VM) and DNA encoding techniques, aims to produce secure and high-performance s-boxes. To evaluate the reliability of the s-boxes, fundamental cryptographic criteria such as nonlinearity (NL), strict avalanche criterion (SAC), differential probability (DP), linear approximation probability (LAP), and bit independence criterion (BIC) are considered. Additionally, a novel chaos-based evolutionary optimization algorithm is proposed to optimize the NL criterion of the s-boxes. This algorithm offers a cost-effective and highly efficient alternative compared to classical metaheuristic methods, providing a balanced structure between security and performance. Experimental findings and comparison results demonstrate that the proposed s-boxes offer effective and reliable solutions for modern cryptographic applications, such as secure data transmission and storage. From a broader perspective, the study makes a meaningful contribution to the literature in the field of data security by presenting a high-performance s-box design meeting the security requirements of cryptographic systems and is resilient against current threats.
AtıfScopus25WoS26OpenAlex23İncele - MakaleYalnız künye2026Scopus SJRQ2Oxalic Acid–MAP Synergy in Maintaining Postharvest Grape Quality and Biochemical Content
Küçüker, Emine; Ağlar, Erdal; Sümbül, Ahmet; Demir, Selda; Özcengiz, Ceyda Kizgin; Güzel, Sedat
This study was conducted to investigate the effects of oxalic acid (OA) and modified atmosphere packaging (MAP) applications, both alone and in combination, on the preservation of postharvest quality characteristics of grapes. All samples were stored at 4 ± 1 °C and approximately 80–85% relative humidity for 28 days. The OA + MAP treatment most effectively limited weight loss (10.49%), soluble solids content (SSC; 20.62°Bx), and decay rate (1.78%), while providing the best preservation of total phenolic content (68.25% change), antioxidant activity (53.19% change), and individual phenolic compounds at the end of the storage period. A decrease in color parameters, including L* and a* values, was observed, with OA treatment particularly prominent in preserving the red color. Principal component analysis and hierarchical heatmap analysis confirmed distinct clustering of treatments from the control, highlighting the process efficiency of packaging-based interventions. The combination of OA and MAP treatments was more effective than either treatment alone in reducing quality losses in grapes during storage. Therefore, the widespread use of OA + MAP in commercial storage and marketing processes is recommended.
