İstanbul Sağlık ve Teknoloji Üniversitesi Kurumsal Akademik Arşivi
DSpace@İSTÜN, Üniversite mensupları 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
Sustainable valorization of yellow cherry juice using natural propolis and non-thermal techniques
(Frontiers Media S. A., 2025) Yıkmış, Seydi; Türkol, Melikenur; Tokatlı Demirok, Nazan; Tokatlı, Nazlı; Rüzgar, Ezgi; Mohamed Ahmed, Isam A.; Aljobair, Moneera O.
This study investigated the effects of propolis enrichment and thermosonication conditions on bioactive components, amino acid profile, antioxidant capacity and sensory properties of yellow cherry juice. Temperature (40–50°C), time (4–10 min), amplitude (40–80%) and propolis concentration (40–80 mg/100 mL) were optimized as independent variables using response surface methodology (RSM). Principal component analysis (PCA) analysis revealed that thermosonicated samples (TS-YCJ) were positively correlated with functional components such as chlorogenic acid, caffeic acid, epicatechin and total soluble solids (TSS). The malic acid content reached its highest level at 1,174.38 mg/L in thermosonicated optimized propolis yellow cherry juice (TS-YCJ), whereas this value remained at 1,078.34 mg/L in the pasteurized samples. Thermosonication application significantly increased the antioxidant capacity measured by total phenolic content (TPC), total flavonoid content (TFC) and DPPH radical inhibition. While TPC content reached 268.72 mg GAE/L in thermosonicated optimized propolis yellow cherry juice samples, it remained at 256.27 mg GAE/L in control samples. Among the phenolic compounds, chlorogenic acid (35.42 mg/L) and caffeic acid (12.67 mg/L) increased significantly after thermosonication. In terms of amino acid profile, components such as proline (42.21 mg/L), glycine (38.45 mg/L) and phenylalanine (24.32 mg/L) were found at higher levels in control samples. In sensory analysis, thermosonication samples received high scores in terms of taste, odor and overall acceptability. High R2 values (98.94–99.80%) reveal the strong explanatory power and reliability of the model. These findings indicate that thermosonication and propolis offer an effective combination to improve the functional properties, sensory quality and phenolic compound profile of yellow cherry juice.
Impact of structural and CFD analysis on the cost of biogas-fueled gas engine exhaust pipes
(Ahmet ÇALIK, 2025) Kaymaz, Rabia; Ak, Mine; Tanrıver, Kürşat
In this study, the effects of exhaust pipe design used in biogas-fueled cogeneration systems on engineering performance and cost were investigated. First, the existing system was analyzed by field work, and then structural analysis was applied with CFD (Computational Fluid Dynamics). The exhaust pipe route, pipe diameter, and material thickness of the existing system were evaluated, and design improvements were suggested. It was determined that the shorter pipeline application with the changes made in the pipe route and layout reduced pressure losses. Despite the use of an exhaust pipe with a smaller diameter and made of thinner material in the proposed new design, compliance with the standards was ensured, and it was shown to be safe against wind loads with finite element analysis. Considering the calculated maximum wind load of 5.52 kN and the weight of the system, the maximum stress value was calculated as 108.691 MPa as a result of the Von Mises stress analysis applied to the exhaust pipe system in the finite element analysis. This value showed that the system was 1.56 times safer. In the deformation analysis, the maximum displacement value was measured as 0.13 mm, and this value is ideal. In the cost analysis, it was determined that the proposed new system provides a cost reduction of approximately 53% compared to the existing system. The results obtained emphasize the importance of engineering analysis in exhaust pipe design, and show the applicability of the approach to increase economic and environmental sustainability in industrial facilities.
Suicide risk in psychiatric patients: An analysis of demographic and psychosocial factors
(SOCIAL SCIENCES STUDIES JOURNAL, 2025) Er, Filiz; Duyan, Veli; Özkan, Cengiz; Taymur, İbrahim
The aim of this study is to assess the likelihood of suicide in patients diagnosed with psychiatric disorders and currently receiving treatment, and to examine the relationship between this likelihood and demographic data, as well as psychosocial factors. Using a descriptive and cross sectional model, the data from 165 participants were collected and evaluated through a personal information form and the Suicide Probability Scale (SPS). The study revealed significant relationships between suicide risk and variables such as age, education level, marital status, place of residence, and types of social support. It was also highlighted that the participants generally had a negative perception of their psychological health, and individuals lacking emotional social support showed higher levels of hopelessness and negative self-concept. Furthermore, individuals receiving low social support were found to have a higher suicide risk. The findings indicate that social work professionals can play a significant role in identifying individuals at risk for suicide and developing preventive measures. These results point to the necessity of strengthening social support systems and improving psychological health services.
