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
Online Peer Feedback Versus Online Teacher Feedback? Effect of Online Feedback on Students’ Self-Regulated Learning
(Springer Science and Business Media B.V., 2025) Öztürk, Mücahit; Yüce, Erkan; Mıhcı Türker, Pınar
This study investigated the impact of online peer and teacher feedback on students' self-regulated learning and analysed students’ perceptions of online peer feedback on self-regulated learning development. The study employed a mixed method by collecting quantitative and qualitative data together. The study comprised 45 pre-service English as a Foreign Language (EFL) teachers as participants, and they were assigned to experimental and control groups. While online peer feedback was used in the experimental group, online control group was employed in the control group. Padlet online environment was used for online peer feedback and online teacher feedback. The quantitative results showed that the experimental group students had higher self-regulated learning levels than those in the control group. The qualitative results revealed that online peer feedback can have a positive impact on students’ self-regulated learning.
Investigation on the Effect of Opening Size and Position on Wind-Driven Cross-Ventilation in an Isolated Gable Roof Building
(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Demir, Hacımurat; Aktepe, Burak
In this study, the influence of window opening sizes and positions on wind-induced cross ventilation performance in an isolated gable roof building was numerically investigated using the k-ω SST turbulence model. The results obtained from numerical analyses to evaluate the ventilation efficiency of different configurations show that larger inlet openings significantly increase the ventilation rates and the WO5 model reaches the highest ventilation rate of 0.004089 m3/s with an improvement of 37.27% compared to the reference model. As with the WO1 model, smaller inlet openings limited the air intake, reducing ventilation efficiency and indoor air quality. In terms of outlet window opening sizes, the LO5 model showed the highest ventilation efficiency, improving ventilation by 28% compared to reference model, while smaller outlet openings, as in the LO1 model, were associated with significantly lower performance. Additionally, when evaluating window opening locations, configurations with higher exit openings generally exhibited superior ventilation rates. The best overall ventilation performance was achieved in the Upper-Lower configuration at 0.003129 m3/s. The findings emphasized the critical role of window design in natural ventilation performance. Larger and strategically located window openings optimize airflow, increase ventilation efficiency and improve indoor air quality, providing valuable information for energy-efficient building design.
Nanoliposomal Encapsulation and Purification of Angiotensin-Converting Enzyme Inhibitor Peptides from Ulva rigida
(American Chemical Society, 2025) Şensu, Eda; Koku, Harun; Demircan, Evren; Şişman, Sebahat; Gülseren, İbrahim; Karaduman, Tuğçe; Çakır, Bilal; Okudan, Emine Şükran; Duruksu, Gökhan; Özçelik, Beraat; Yücetepe, Aysun
Angiotensin-converting enzyme inhibitory peptides derived from natural sources may be effective in the treatment of hypertension without causing side effects compared with existing angiotensin-converting enzyme (ACE) inhibitors. Naturally derived antihypertensive peptides are therefore considered a promising alternative for the prevention or treatment of hypertension. Therefore, the study aimed to purify and identify ACE-inhibitory peptides from the green macroalgae Ulva rigida. In addition, the encapsulation of the purified peptides showed the highest ACE-inhibitory activity by chitosan-coated nanoliposomes, and the characterization of nanoliposomes was evaluated. Protein hydrolysates were obtained from U. rigida through enzymatic hydrolysis. The hydrolysates were separated into molecular weights of <3, <5, and <10 kDa through ultrafiltration membrane separation (UFMS). The <3 kDa fraction (UFMS-3) that exhibited the highest ACE-inhibitory activity (77.02%, 1 mg/mL) was purified using ion-exchange chromatography. Fraction-1 (IEC-F1) obtained from the ion-exchange purification showed an impressive 82.03% ACE-inhibitory activity. Moreover, peptide sequences of IEC-F1 were identified by LC-MS/MS, and their bioactive properties were determined in silico. After that, IEC-F1, with a strong ACE-inhibitory activity, was loaded into chitosan-coated nanoliposomes to improve their stability for encapsulation. Physical stability (ζ-potential, polydispersity index, particle size), thermal (DSC) and morphological properties (SEM), and FT-IR analyses were carried out for the characterization of nanoliposomes. Encapsulation efficiency was found to be 92.0 ± 4.5%. After encapsulation, the ACE-inhibitory activity of IEC-F1 was protected by 37.5%. Overall, the obtained findings indicate that the hydrolysate produced by the successive hydrolysis of U. rigida macroalgae with pepsin and trypsin contains peptides with strong ACE-inhibitory action. Furthermore, the chitosan-coated nanoliposome method was determined to be an effective carrier for the delivery of peptide fractions, showing ACE-inhibitory activity. The formulation of chitosan-coated nanoliposomes for peptide fractions from U. rigida represents an innovative approach that allows the development of functional and stable products.
Fritillaria behcetiana (Liliaceae), a new species from eastern Anatolia (Türkiye)
(Magnolia Press, 2025) Yapar, Yakup; Tekşen, Mehtap
Fritillaria behcetiana sp. nov. is described as a new species from Bingöl Province in eastern Anatolia, Türkiye. It is closely related to F. shehbazii, F. chlororhabdota and F. pinardii, but differs from them in several morphological features, including leaf lenght and colour, perianth segment size and colour, anther colour and length, filament length, style lenght and branching. The new species is described in detail, including distribution, ecology, conservation status and photographs with comparisons to F. shehbazii, F. chlororhabdota and F. pinardii.
Effects of artichoke (Cynara scolymus) leaf extract on the growth, blood, and biochemistry parameters of Nile tilapia (Oreochromis niloticus)
(Springer Science and Business Media B.V., 2025) Esen, Ramazan; Öz, Mustafa; Dikel, Suat
In this study, artichoke leaf extract (ALE) was added to the Nile tilapia diet at different ratios (0.00%, 1.00%, 2.00%, and 3.00%) for 30 days to investigate its effects on growth performance, hematological parameters, and blood biochemistry. A total of 240 fish with an average initial weight of 33.9 ± 1.14 g were used. The results showed that ALE supplementation significantly improved growth performance, with the best results observed at 2.00% inclusion (final weight: 58.01 ± 0.18 g, FCR: 1.48 ± 0.02, SGR: 1.79 ± 0.01) (p < 0.05). Hematological analysis revealed an increase in hemoglobin (Hb) levels (control: 9.18 ± 0.62 g/dL; 2.00% ALE: 12.83 ± 1.19 g/dL) and a decrease in white blood cell count (control: 3.54 ± 0.06 m/mm3; 2.00% ALE: 3.39 ± 0.07 m/mm3) (p < 0.05). Blood biochemistry results indicated a significant reduction in glucose (control: 73.67 ± 4.16 mg/dL; 2.00% ALE: 51.00 ± 2.00 mg/dL) and cholesterol levels (control: 227.67 ± 6.11 mg/dL; 2.00% ALE: 117.67 ± 3.21 mg/dL) (p < 0.05), suggesting improved metabolic balance. The findings indicate that 2.00% ALE supplementation enhances growth performance and may positively influence fish health by modulating blood parameters, making it a promising natural additive for sustainable aquaculture.
