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
Acute neurochemical, psychophysiological, and cognitive responses to small-sided games vs. running-based HIIT in young, male soccer players
(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Birinci, Yakup Zühtü; Pancar, Serkan; Soylu, Yusuf; Topçu, Hüseyin; Koçyiğit, Aygül; Sarandöl, Emre; Şimşek, Hasan; Şahin, Şenay
This study aimed to compare the immediate effects of small-sided games (SSGs) and running-based high-intensity interval training (HIITrb) on serum brain-derived neurotrophic factor (BDNF) levels, cognitive performance, and enjoyment in young, male soccer players. Methods: Twenty-four soccer players [age: 19.2 ± 0.8 years] completed one session each of four-a-side SSG or HIITrb in a randomized, counterbalanced, and crossover design, with a one-week washout period. Blood samples and Trail Making Tests (TMTs) A and B were measured before and after exercise. Heart rate (HR) was monitored throughout the games, and ratings of perceived exertion (RPE) and enjoyment were collected at the end of the measurements. Results: The results show no significant effects of time (p > 0.775), group (p > 0.276) or time × group interaction (p > 0.199) on BDNF levels. For TMT-A, the time effect (p = 0.866) and group effect (p = 0.057) were not significant; however, the time × group interaction was significant (p < 0.019), indicating a superior performance in the SSG compared to HIITrb. In the TMT-B, significant effects were observed for both time (p < 0.001) and group (p < 0.001), while the time × group interaction effect was not statistically significant (p > 0.061). Furthermore, enjoyment levels did not differ significantly between conditions (p = 0.976). Conclusions: These findings suggest that four-a-side SSG may enhance processing speed compared to HIITrb without changes in serum BDNF levels. Coaches may consider using 4v4 SSG formats in early training sessions or warm-ups to stimulate processing speed and mental readiness in young soccer players.
Assessment of the domestic sewage sludge by different drying methods: solar radiation and thermal energy source
(Global NEST, 2025) Gök, Gülden; Düzgün, Türkay
The amount and properties of the sludge produced in wastewater treatment plants depend on the composition of the wastewater, the type of wastewater treatment used and the disposal method applied to the mud. The sludge that occurs during mechanical, biological and chemical treatment methods must be subjected to some pre-treatment in terms of both environmental problems and the threat of human health. Sludge samples were taken from the sludge dewatering station, which is the last point of a wastewater treatment plant sludge treatment, and tested in pilot scale hybrid sludge drying system. In the study, drying methods were investigated in the context of urban wastewater treatment plants in Ankara province under the final disposal of sludge from urban wastewater treatment plants. The most suitable solution would be to dry the sewage sludge in Ankara in a hybrid system with solar radiation and thermal energy sources (cogeneration with solar panels) in a system that will provide uninterrupted power to the drying system. This thermal source can be provided from the existing cogeneration system in the plant. Addition of solar panels to the sludge drying system is an important option in order to obtain better efficiency than solar radiation-based drying system.
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.
