İstanbul Galata Üniversitesi Kurumsal Akademik Arşivi

DSpace@Galata, İstanbul Galata 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

Öğe
The use of artificial intelligence (AI) in tourism employment: employees’ perceptions and business strategies
(Emerald Group Publishing, 2026) Kızıldemir. Özgür; Şengel, Ümit; Çakmak, Muzaffer; İbiş, Salim; İnan, Ramazan
Purpose – The study aims to focus on the challenges that artificial intelligence (AI) brings to career decisions among tourism employees, while on the other hand, it focuses on how tourism employees’ AI risk perceptions affect their career decisions. In addition, another aim of the study is to reveal problem-solving strategies and future vision from a sector-based and managerial perspective for possible employment problems. Design/methodology/approach – In the first stage of my study, which used a mixed-method approach, data was obtained from 423 tourism employees (accommodation, food and beverage and travel) in Istanbul through a survey, while in the second stage, data was obtained from 25 managers (accommodation, food and beverage and travel) working in tourism establishments in Istanbul through interview forms. Findings – The results of the study revealed that AI risk perceptions affect tourism employees’ career decisions, while the professional motivation and anxiety levels of employees significantly mediated this effect. For the potential employment problems that these results will reveal, sub-sectors in tourism are trying to produce solutions with strategies such as technology investments and employee adaptation. Originality/value – This study fills an important gap in the literature by revealing that AI, which has the potential to increase service delivery and operational efficiency, affects employees’ career decisions and that businesses act with the mission of producing solutions with this awareness.
Öğe
Psychological Flexibility and Academic Self-Efficacy
(Hogrefe AG, 2026) Aksoy, Şeyhmus; Konuk, Ayşe; Alkhulayfi, Abdulmohsen Mohammed Abdullah; Gomez-Salgado, Juan; Yıldırım, Murat
Introduction: Despite the beneficial effects of academic self-efficacy, there is a relatively limited focus on the academic self-efficacy of higher education students compared to studies on student self-efficacy in other educational stages. Aim: The present study employs a moderated mediation model to investigate whether well-being literacy mediates the relationship between psychological flexibility and academic self-efficacy, while also exploring how burnout-driven selfstigma is associated with these direct and indirect relationships. Methods: A cross-sectional research design was employed in the present study. The sample comprised 316 students (82.6% female; M = 22.28, SD = 3.38). Participants completed the Academic Self-Efficacy Scale, the Psychological Flexibility Scale, the Well-Being Literacy Scale, and the Burnout-Driven Self-Stigma Scale. Results: Our study indicated that psychological flexibility was associated with reduced academic selfefficacy both directly and indirectly through well-being literacy. However, conditional direct and indirect effect results suggested that higher levels of burnout-driven self-stigma were related to decreased positive direct and indirect effects. Discussion/Conclusion: This study provides evidence to improve our understanding of how psychological flexibility relates to academic self-efficacy. While research on burnout-related self-stigma and well-being literacy remains limited, this study highlights how these variables were examined within the proposed model as potential moderator and mediator constructs.
Öğe
Asynchronous recovery of medial and lateral gastrocnemius mechanical properties and jump performance following localized plantar flexor fatigue
(BMC, 2026) Şahbaz, Yasemin; İlez, Ali; Batur, Nergiz
Objective: To investigate the acute and short-term (24 h) effects of localized plantar flexion fatigue on muscle mechanical properties, countermovement jump (CMJ) kinetics, and dynamic balance, focusing on recovery profiles of the gastrocnemius medialis (MG) and lateralis (LG). Design: Prospective, repeated-measures experimental study. Methods: Twenty-eight healthy volunteers (n = 28) performed a standardized unilateral isometric plantar flexion fatigue protocol until task failure (Borg CR-10 ≥ 8). Assessments were conducted at baseline, immediately post-fatigue, and 24 h post-fatigue (24 h). Outcomes included myotonometric properties (tone, stiffness, elasticity, relaxation time, and creep) of the MG and LG via MyotonPRO, CMJ kinetics via force plate, and dynamic balance via the Modified Star Excursion Balance Test (mSEBT). Results: Significant Time × Region interactions were found for stiffness (P = 0.038, ηp² = 0.276) and relaxation time (P = 0.024, ηp² = 0.171). Both muscle heads showed an acute decrease in stiffness (P < 0.001); however, LG stiffness recovered by 24 h (P = 0.330), while MG stiffness remained reduced (P < 0.05). Although CMJ height recovered at 24 h (P = 0.842), eccentric and braking phase durations remained prolonged (P < 0.001; ηp² = 0.357 and ηp² = 0.264), indicating altered neuromuscular strategies. For dynamic balance, a delayed impairment was observed in anterior reach distance, which declined only at 24 h compared to baseline (P = 0.021, ηp² = 0.133). Conclusion: Localized plantar flexion fatigue induces region-specific mechanical alterations and asynchronous recovery. Restoration of jump height at 24 h masks persistent deficits in eccentric phase durations and MG stiffness. These findings highlight a “neuromuscular vulnerability window” at 24 h post-fatigue, where delayed impairments in MG mechanics and anterior stability may increase potential susceptibility to injury despite apparent recovery. Practically, monitoring head-specific muscle mechanics, rather than global performance outcomes, is critical during this 24 h window to optimize training modification and guide objective return-to-play decisions. Trial registration: NCT07457398 (Registration date: February 25, 2026). © The Author(s) 2026.
Öğe
Classification of malignant/benign groups in lung cancer by machine learning and investigation of feature significance of parameters
(Walter de Gruyter GmbH, 2026) Çalışkan, Gönül; Alataş, Emre; Köksal, Sevilay; Akyel, Reşit; Çavdar, İffet; Alçin, Göksel; Arslan, Esra; Çiftçi-Küsbeci, Tuba; Dereli, Elçin; Akgün, Elif; Tanyıldızı-Kökkülünk, Handan; Yiğit, Şafak
This study aimed to apply machine learning (ML) models to enhance lung cancer (LC) classification, distinguishing malignant from benign tumors, using data from 73 patients. The dataset included PET/CT biomarkers and demographic factors, with SMOTE applied to address class imbalance. Three models were evaluated using 10-fold cross-validation to compare Random Forest (RF), Decision Tree (DT), Extra Trees Classifier (ETC), and XGBoost algorithms based on accuracy and AUC. ETC performed best in Model 1 (86% accuracy, AUC 0.95), RF in Model 2 (94% accuracy, AUC 0.97), and XGBoost in Model 3 (94% accuracy, AUC 0.98). XGBoost consistently outperformed others, particularly in Model 3, which included age and smoking. Feature importance analysis highlighted SUVmax as the most predictive variable, with smoking having a moderate influence and gender being minimal. Integrating clinical and lifestyle data with PET/CT parameters significantly improved LC classification. XGBoost emerged as the most effective model, demonstrating that comprehensive models enhance diagnostic accuracy beyond traditional metrics. © 2026 the author(s), published by De Gruyter, Berlin/Boston.
Öğe
Are sacral stress fractures in young women truly rare? a retrospective MRI analysis of 1970 patients
(BMC, 2026) Bayram, Yusuf; Doğan, Selman; Yalvaç, Bestami; Aksoy, Süleyman Hilmi; Karataş, Muhammed Enes
Background Sacral stress/insufficiency fractures (SSFs) are underrecognized causes of postpartum low-back/pelvic pain and are frequently misattributed to lumbar disc disease. To determine the MRI-based detection rate and clinical/ imaging characteristics of SSFs in women aged 18–50 years undergoing lumbosacral MRI, with subgroup analyses for postpartum versus non-postpartum status. Methods Retrospective review of 2400 lumbosacral MRI examinations (January 2020–December 2024) corresponding to 1970 unique women. SSFs were identified by a fellowship-trained musculoskeletal radiologist. Prespecified exclusions (chronic corticosteroid use, major pelvic trauma, incomplete follow-up) yielded the analytic cohort. Group comparisons reported effect sizes (Hedges’ g for continuous; risk difference [RD]/odds ratio [OR] for binary) with 95% CIs. Results Crude MRI-based detection rate: 1.52% (30/1,970; 95% CI, 1.07–2.17); analytic MRI-based detection rate: 1.17% (23/1,970; 95% CI, 0.78–1.75). Median age 34 years (range 22–49); 10/23 (43.5%) postpartum. Five cases (21.7%) were initially misdiagnosed. Fractures most often involved the sacral ala (right 12, left 10, bilateral 1). Compared with non-postpartum patients, postpartum patients had lower hemoglobin (**11.5 vs 12.6 g/dL; p = 0.007; Hedges’ g = 1.21, 95% CI 0.34–2.09) and hematocrit (**33.9% vs 37.3%; p = 0.007; g = 1.21, 95% CI 0.34–2.09); vitamin D was lower but nonsignificant (**15.4 vs 20.3 ng/mL; p = 0.204; g = 0.53, 95% CI − 0.28–1.34). Overall vitamin D status (n = 21): deficient < 20 ng/mL 11/21 (52.4%), insufficient 8/21 (38.1%), sufficient ≥ 30 ng/mL 2/21 (9.5%). The reported frequency reflects an MRI-based detection rate within a selected cohort of symptomatic women undergoing lumbosacral MRI and should not be interpreted as the true population prevalence of sacral stress fractures. Conclusion Sacral stress fractures in young women, particularly in the postpartum period, may be underrecognized in symptomatic patients presenting with persistent lo