Recep Tayyip Erdoğan Üniversitesi Kurumsal Akademik Arşivi
DSpace@RTEÜ, Recep Tayyip Erdoğan Üniversitesi tarafından doğrudan ve dolaylı olarak yayınlanan; kitap, makale, tez, bildiri, rapor, araştırma verisi gibi tüm akademik kaynakları uluslararası standartlarda dijital ortamda depolar, Üniversitenin akademik performansını izlemeye aracılık eder, kaynakları uzun süreli saklar ve yayınların etkisini artırmak için telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Thermal performance improvement in the solar air collector system using reduced graphene oxide nanoparticles
(Springer, 2025) Sathyamurthy, Ravishankar; Ali, Hafiz Muhammad; Ali, Usman; Cüce, Erdem; Gopalsamy, Selvakumar; Bahaidarah, Haitham M. S.; Kadhim, Saif Ali
This study experimentally demonstrates that enhancing solar absorptance and heat transfer in a single-pass solar air collector can be achieved through a coating of reduced graphene oxide-doped black paint. The introduction of carbon-based nanoparticles results in an augmented thermal conductivity in a turpentine-oil nanofluid. Subsequently, a homogeneous blend of the thermally modified turpentine oil with the black paint is coated onto the absorber plate, resulting in a consequent increase in absorptance across the incident solar spectrum. In this regard, two different solar air collectors were fabricated, namely (i) a single-pass flat plate SAC with BP coating and (ii) a single-pass flat plate SAC with rGO-doped BP coating as surface coating. The thermal performance of both solar air collectors was evaluated across a range of airflow rates. Data obtained during the experiments demonstrated that the collector with the surface coating exhibited superior thermal response: specifically, higher absorber temperatures, increased exit air temperatures, and an improved temperature difference between the exit and inlet air streams. However, the increase in the flow rate of air through the rectangular channel decreases the absorber, exit air temperature, and temperature difference between the exit and inlet of the rectangular channel. Furthermore, the results also showed that at the higher flow rate of air through the channel, the Nusselt number and the heat transfer coefficient increase from coated and uncoated absorber plates. From the experimental results, the average daily efficiency of the single-pass SAC with BP coating ranged from 30.12 to 67.2% for a flow rate of 0.01 to 0.03 kg s−1. However, with surface coating and improved surface roughness, the daily efficiency increased to 34.6 to 79.5%. Furthermore, in this study, a response surface methodology is employed to optimize the exit, absorber temperature, and the change in temperature between exit and inlet, considering the impact of solar radiation, ambient temperature, and concentration of nanoparticles. Moreover, the correlations are expressed in the form of a quadratic function.
Rapid synthesis of highly monodisperse AgSbS2 nanocrystals: unveiling multifaceted activities in cancer therapy, antibacterial strategies, and antioxidant defense
(Beilstein-Institut Zur Forderung der Chemischen Wissenschaften, 2025) Ulusu, Funda; Sarılmaz, Adem; Ulusu, Yakup; Özel, Faruk; Kuş, Mahmut
Nanocrystals (NCs) of silver antimony sulfide (AgSbS2) in the cubic phase were successfully synthesized using the hot-injection method. This study is the first to investigate the cytotoxic effects of these NCs on human breast adenocarcinoma (MCF-7), colon cancer cell lines (HT-29), and fibroblast cell lines (L929). Additionally, the antibacterial properties of the NCs against gram-positive (Staphylococcus aureus and Bacillus subtilis) and gram-negative (Escherichia coli) pathogenic bacteria were evaluated, along with their DPPH scavenging activities. The crystal structure of the synthesized NCs was elucidated through XRD analysis, revealing characteristic diffraction peaks corresponding to the (111), (200), (220), (311), and (222) planes of the AgSbS2phase. TEM and SEM techniques were used to comprehensively characterize the NCs. The results showed that spherical NCs were predominantly formed, with an average diameter of approximately 32 ± 10 nm. Cytotoxicity studies demonstrated a significant inhibitory effect of the NCs, particularly on cancer cell lines (MCF-7 and HT-29), in a dose-dependent manner over a 24 h period. These findings highlight the potential of the NCs as anticancer agents. Furthermore, the synthesized NCs demonstrated potent anti-bacterial properties against the tested microorganisms and notable antioxidant effects by efficiently eliminating DPPH activity. This research highlights the potential of AgSbS2NCs as versatile agents with applications in biomedical and environmental domains, including cancer therapy, antimicrobial strategies, and free radical neutralization.
Unraveling the morphophysiological, biochemical, and yield responses of maize genotypes to contrasting nitrogen conditions using multivariate approaches
(TUBITAK, 2025) Jan, Muhammad Faheem; Lin, Yu; Liaqat, Waqa; Altaf, Muhammad Tanveer; Liu, Changzhuan; Shuai, Wang; Albayrak, Önder; Li, Ming
Genotypic variation plays a pivotal role in modulating the activity of nitrogen (N) assimilating enzymes, photosynthetic rate, N accumulation, plant growth, and yield. Despite this, the extent to which growth and N-assimilating enzymes exhibit differential responses across genotypes and their influence on yield and nitrogen use efficiency (NUE) remains inadequately explored. This study aimed to elucidate genetic variations among two inbred maize lines (Huang C and 178) and their hybrid (Huang C × 178) for key morphophysiological and biochemical traits under contrasting N conditions. Multivariate statistical methods, including principal component analysis (PCA) and structural equation modeling (SEM), were used to analyze and identify significant genotypic differences across most traits. The primary contributors to genetic variation were identified as N-assimilating enzymes, photosynthetic rate, N accumulation, and ear traits. Complete N deficiency significantly reduced root development, photosynthetic rate, and N-assimilating enzyme activities. Correlation analysis revealed strong positive relationships among N-assimilating enzyme activities, shoot N accumulation, and grain N accumulation, indicating that enhanced biomass production promoted higher grain yield. Moreover, strong positive correlations between N-assimilating enzymes and grain yield demonstrate the critical role of these enzymes in optimizing yield and NUE. Nitrogen use efficiency indices showed significant differences among genotypes, particularly in NUE, nitrogen recovery efficiency (NRE), nitrogen partial factor productivity (NPFP), nitrogen dry matter productivity (NDMP), and nitrogen harvest index (NHI). The highest heterosis was observed in N metabolism enzymes, photosynthetic rate, N accumulation, and yield components, indicating these traits as key improvement drivers. The study concluded that genetic variation in critical traits, such as N-assimilating enzyme activity, photosynthetic rate, N accumulation, and yield components, confers a significant advantage to the hybrid. These findings have practical implications for maize breeding programs, as they highlight the potential for improving NUE and yield through genetic selection. This could contribute significantly to sustainable agriculture by optimizing N input and minimizing environmental impact.
Arbutin protects against methotrexate-induced pulmonary injury in rats via modulation of oxidative stress, inflammation, and ER stress
(Frontiers Media SA, 2025) Türkmen Alemdar, Nihal; Demir, Selim; Yuluğ, Esin; Erdoğan, Nadire Sevdenur; Ayazoğlu Demir, Elif; Menteşe, Ahmet; Aliyazıcıoğlu, Yüksel
Introduction: Methotrexate (MTX) is a widely utilized agent in the treatment of cancer, yet it is notable that it can induce pulmonary toxicity in cases of high-dose chemotherapy. Arbutin (ARB) is a hydroquinone compound that is present in members of the Lamiaceae, Ericaceae and Rosaceae families, and experimental studies have demonstrated its capacity for lung protection. The present study aimed to determine whether ARB could reduce the pulmonary toxicity of MTX and to explore the underlying mechanisms. Methods: The lung toxicity rat model was created by means of a single intraperitoneal injection of MTX at a dose of 20 mg/kg. The animals were then treated with two different doses of ARB (50 and 100 mg/kg) for a period of 7 days. Following the conclusion of the treatment period, a histopathological examination of the lung tissue samples was conducted. The remaining tissue samples were evaluated for oxidative stress (OS), inflammation, endoplasmic reticulum stress (ERS), sirtuin 1 (SIRT1)/nuclear factor erythroid-related factor 2 (Nrf2) pathway, and apoptosis for further analysis. Results: The administration of MTX resulted in the inhibition of SIRT1/Nrf2 in lung tissue, accompanied by an escalation in OS, inflammation, ERS, and apoptosis levels. This was concomitant with a significant enhancement in the severity of histopathological findings. Nevertheless, ARB reversed MTX-induced biochemical and pathological changes through SIRT1/Nrf2 modulation. Discussion: It is asserted that further comprehensive studies are required to support the hypothesis that ARB has the potential to improve oxidative and inflammatory lung injury via SIRT1/Nrf2 modulation.
Determining the relationship of food neophobia, digital addiction, body image perception on social media with dietary inflammatory index among adolescents
(Frontiers Media SA, 2025) Albayrak, Rümeysa; Demirel Özbek, Yağmur
Background: Adolescence is a critical period in which both physical and psychological development accelerates and foundational dietary behaviors are established. This study aims to examine the relationships of food neophobia, digital addiction, body image perception on social media with the dietary inflammatory index (DII) among high school adolescents. Method: This cross-sectional and descriptive study was conducted with a total of 354 high school students, including 200 females and 154 males. Data were collected through questionnaires and face-to-face interviews. The questionnaire included sections on general information, dietary habits, the Food Neophobia Scale (FNS), the Child and Adolescent Digital Addiction Scale (CADAS), the Appearance-Related Social Media Consciousness Scale (ASMC), and a 3-day dietary intake record. Data analysis was performed using IBM SPSS version 25. Results: The mean DII score was 3.23 ± 1.66, the mean FNS score was 38.33 ± 10.81, the mean CADAS score was 35.82 ± 11.53, and the mean ASMC score was 41.31 ± 17.71. Participants who skipped meals had significantly higher DII, CADAS, and ASMC scores (p < 0.05). Regular breakfast consumption was associated with lower DII and CADAS scores (p < 0.05). A positive correlation was found between DII and CADAS, as well as between CADAS and ASMC. FNS scores showed a negative correlation with CADAS only among female participants. Conclusion: To support healthy adolescent development and mitigate the risks posed by the digital age, it is recommended to design and implement comprehensive intervention programs based on school, family, and individual levels, utilizing multidisciplinary approaches.
