Aksaray Üniversitesi Kurumsal Akademik Arşivi
DSpace@Aksaray, Aksaray 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 telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Microplastics in long-eared owl (Asio otus) pellets: tracing contamination through prey
(Springer Verlag, 2025) Seyfe, Merve; Çırak, Tamer; Kankılıç, Tolga; Tavşanoğlu, Ülkü Nihan
Microplastic pollution is a pervasive global environmental problem affecting ecosystems and pose a potential threat by entering the food chain. Due to their small size, microplastics are easily ingested by organisms at the base of the food web. Owls, as nocturnal predators, are vulnerable to microplastic bioaccumulation through their prey, including small mammals, reptiles, and birds. This study investigates microplastic exposure in long-eared owls (Asio otus) by analyzing their pellet contents. A total of 292 pellets were collected from agricultural (n = 129), steppe (n = 116), and forest (n = 47) habitats in Ankara, Türkiye, over nine months. The most common microplastics found were fibers (78%), followed by films (14%) and fragments (8%), with sizes ranging from 0.5 to 4.4 mm. Microplastic distribution varied across habitats: 63% were found in steppe, 23% in agriculture, and 14% in forests particularly during non-breeding periods. The microplastics included polyethylene terephthalate (PET), ethylene-vinyl acetate (EVA), and polypropylene (PP), among others. Harting’s vole was the primary rodent prey. A significant correlation was found between prey abundance and microplastic levels, suggesting trophic transfer through food webs. Microplastic concentrations were significantly higher in areas characterized by intensified anthropogenic activity. The study underscores the importance of protected areas with strict human activity regulations in reducing microplastic contamination, highlighting the need for targeted conservation and pollution management efforts to protect wildlife and ecosystems.
Improving stability and buckling resistance of self-supporting ısotrussed telecommunication tower under wind load: an evaluation according to TIA-222-G standards
(Faculty of Civil Engineering, Semnan University, 2025) Faharidine, Mahamoudou; Usama Aslam, Muhammad; Choufaikat, Mohamed Moutuou
Despite the growing demand for durable telecommunication infrastructure, tower stability and durability remain significant challenges. The self-supporting isotrussed telecommunication tower (SSITT) offers a promising solution, but its performance under wind loads requires further improvements. This paper investigates SSITT stability and provides guidelines for wind load calculations based on the Telecommunications Industry Association Standard 222 Revision G (TIA-222-G). The isotruss, a lightweight lattice structure made from advanced composite materials, is analyzed using ABAQUS finite element software. Two 10 m 8-node SSITTs, using carbon/epoxy as the material, were modeled. The results show that the maximum displacements of 45.17 mm (Model 1) and 47.29 mm (Model 2) at the top are within acceptable limits, while the maximum stresses of 135.6 MPa (Model 1) and 198.9 MPa (Model 2) are below the material’s limit of 306 MPa. The study found that the longitudinal member experiences the highest stress levels, which may lead to buckling. To improve performance and durability, it is recommended that the longitudinal member be designed with a larger radius than the helical member.
Investigating the encapsulation efficiency and stability of purple onion peel anthocyanin: effects of storage conditions
(Wiley-Blackwell, 2025) İncegül, Yasemin; Berktaş, Serap; Çam, Mustafa
Anthocyanins are bioactive compounds widely recognized for their antioxidant and health-promoting properties; however, their application in food systems is often limited due to instability under environmental conditions. Purple onion peel, a rich and underutilized source of anthocyanins, was selected as a sustainable raw material for valorization. Encapsulation of anthocyanins derived from purple onion peel using different wall materials: sucrose (CC), HI-CAP, a modified starch known for its excellent emulsifying properties, and sodium alginate (ALG) were designed. This study was conducted to encapsulate anthocyanins from purple onion peel using different wall materials. Oven drying (HI-CAP), ionic gelation (ALG) and co-crystallization (CC) were selected as the encapsulation method. Encapsulation efficiency was highest with HI-CAP (82.56%) and lowest with CC (9.80%). ALG capsules showed the strongest bioactivity, with the highest total phenolics (26.94 mg GAE g−1), flavonoids (5.33 mg CE g−1), and antioxidant capacity. HI-CAP capsules had the lowest bulk (0.42 g/cm3) and tapped (0.48 g/cm3) densities but poorer flowability as indicated by higher Carr index (12.52) and Hausner ratio (1.14). CC and ALG provided better flow properties. CC had the highest water solubility and dry matter, while ALG had lower water activity and a darker color. Stability tests under various temperatures (4, 25, and 65°C), light, and oxygen showed that ALG and HI-CAP offered better protection of anthocyanins, especially at 4°C. However, significant degradation occurred at 65°C and under sunlight. Overall, ALG and HI-CAP capsules were most effective in preserving anthocyanin stability and bioactivity, making them suitable for food and pharmaceutical use.
The effects of in ovo administered of monosodium glutamate on the liver development in chicken embyos
(Springer Science and Business Media B.V., 2025) Bölükbaş, Ferhan; Yavuz, Orhan; Öznurlu, Yasemin; Özaydın, Tuğba; Sur, Emrah
Monosodium glutamate (MSG) is a widely used flavor enhancer/food additive around the world. The aim of this investigation was to analyze the effects of MSG administered in ovo on the development of the liver in chicken embryos using histological and immunohistochemical techniques. Four hundred ten fertilized hen’s eggs were categorized into five groups as follows: a control group, a distilled water group, and those containing MSG at three different concentrations, 0.12, 0.6, and 1.2 mg/g egg groups. The test solutions were injected into the yolk of eggs at just prior to incubation. The eggs from each group were opened randomly on the eighteenth and twenty first days of incubation to obtained 6 live embryos, and pieces of liver tissue were obtained. Hematoxylin and eosin, Crossmon's triple staining, and immunohistochemical staining of caspase-3 was performed. Histopathological alterations, including inflammatory cell infiltration and sinusoidal enlargement, were noted in the MSG-treated groups. Furthermore, MSG caused hydropic and vacuolar degenerations in the liver and to induced detachment in the alignment of the Remark cords, and an increased in caspase-3 positivity in the hepatocytes. Finally, it was found that in ovo administered of MSG affect on the embryonic development of the liver. © The Author(s), under exclusive licence to Springer Nature B.V. 2025.
Evaluation of the effects of monosodium glutamate on the development of the cerebellum in chicken embryos
(Springer Science and Business Media B.V., 2025) Bölükbaş, Ferhan; Öznurlu, Yasemin
Monosodium glutamate (MSG) is a globally used food additive in the modern diet. This study aimed to search the impact of varying doses of MSG administered on embryonic development of the cerebellum. A total of 410 fertilized chicken eggs were randomly assigned to five groups: an untreated control group, a vehicle control group, and groups receiving low-dose (0.12 mg/g egg), medium-dose (0.6 mg/g egg), and high-dose (1.2 mg/g egg) MSG, respectively. The test solutions were injected into the yolk of eggs through a sterile insulin injector. On the 15th, 18th, and 21st days of incubation, the eggs from each group were randomly opened, and six live embryos were obtained. Cerebellum samples of embryos from each group were taken. The number of Purkinje cells in the cerebellum demonstrated a reduction in MSG-treated groups by the 15th, 18th, and 21st days of incubation (p < 0.05). It was noted that the organization of Purkinje cells was irregular, and degeneration and necrosis were also observed in the MSG-treated groups. A notable decrease in the thickness of both the outer and inner granular layers was observed in the MSG-treated groups on the 15th, 18th, and 21st day of incubation. While molecular layer thickness increased on day 15 and 21, decreased on day 18 (p < 0.05). Total cortex thickness decreased significantly in MSG-treated groups. PCNA-positive cells in the cerebellum were found in Purkinje cells, molecular layer cells, and outer and inner granular layer cells. However, there was a decrease in PCNA (+) cell density in MSG-treated groups (p < 0.05).
