Recep Tayyip Erdoğan Üniversitesi Kurumsal Akademik Arşivi
DSpace@RTEÜ, Recep Tayyip Erdoğan 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 yayınların etkisini artırmak için telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Comparative study by FEM of different liners of a transfemoral amputated lower limb
(Nature Research, 2025) Cherif, Aichouba Adda; Abdelmadjid, Moulgada; El Sallah, Zagane Mohammed; Ali, Benouis; Yaylacı, Murat; Abderahmane, Sahli; Yaylacı, Ecren Uzun; Güvercin, Yılmaz
The mechanical behavior of prosthetic liners significantly influences stress distribution, soft tissue protection, and the overall efficiency of the prosthetic. While extensive research has been conducted on liner materials, the impact of liner thickness (2 mm, 4 mm, and 6 mm) on biomechanical response remains underexplored. This study utilizes finite element analysis in Abaqus to investigate how liner material (Gel vs. Silicone) and thickness affect contact pressure (CPRESS), maximum principal strain (Le. Max), shear stress (CSHEAR1), and vertical displacement (U3) at the residual limb-liner interface. A three-dimensional numerical model was developed to simulate stress transmission and displacement behavior under physiological loading conditions. The results demonstrate that liner thickness plays a critical role in modulating pressure distribution and mechanical stability, with Gel providing superior flexibility and shock absorption, whereas Silicone offers enhanced structural integrity. At a thickness of 2 mm, the highest pressure of 0.4656 MPa is recorded. When the thickness is increased to 4 mm, the pressure decreases to 0.4153 MPa, reflecting a reduction of approximately 10.8%. Further increasing the thickness to 6 mm results in a pressure drop of 0.3825 MPa, corresponding to a total reduction of 17.9%. These findings provide quantitative insights into stress attenuation mechanisms, contributing to the optimization of prosthetic liner design for improved clinical outcomes in lower-limb amputees.
Assessment of smoking exposure by urine cotinine levels in severe COVID-19 patients: a case-control study
(Nature Research, 2025) Arpa, Medeni; Şen, Bayram; Kazancıoğlu, Leyla; Kılıç, Hülya
Coronavirus Disease 2019 (COVID-19), caused by SARS-CoV-2, has posed a significant global public health challenge, with long-term sequelae such as post-COVID-19 syndrome continuing to burden health systems. Tobacco use, a major preventable cause of morbidity and mortality, impairs the immune response and exacerbates respiratory diseases, including COVID-19. Passive smoking, an important but often overlooked public health problem, exposes non-smokers to harmful health risks and may contribute to worse outcomes in respiratory disease. This study aims to investigate the relationship between smoking exposure, including passive smoking, and the severity of COVID-19 using urinary cotinine levels to provide objective insights into a critical public health issue. This prospective observational study was conducted over six months in 2021 in the ICU of a tertiary care hospital. Forty-two patients were divided into four groups based on smoking and COVID-19 status: non-smoker/non-COVID-19, smoker/non-COVID-19, non-smoker/COVID-19, and smoker/COVID-19. COVID-19 diagnosis was confirmed by RT-PCR and/or imaging. Data collected included demographic information, clinical scores [APACHE II, mSOFA, GCS], respiratory function [stPaO2/FiO2 ratio], arterial blood gas parameters and routine laboratory findings. Urinary cotinine levels were measured by ELISA and normalised to spot urine creatinine levels to ensure accuracy. Urine cotinine levels were highest in the smoker/COVID-19 group and significantly higher than in the smoker/non-COVID-19 and non-smoker/COVID-19 groups (p = 0.010 and p = 0.002, respectively). Surprisingly, non-smoker/non-COVID-19 patients also had elevated cotinine levels, suggesting exposure to passive smoking. The stPaO2/FiO2 ratio was significantly lower in smoker/COVID-19 patients (p < 0.001), indicating impaired lung function. This study highlights the detrimental effects of smoking exposure, including passive smoking, on the severity of COVID-19. Elevated cotinine levels in non-smokers/non-COVID-19 patients emphasize the widespread public health impact of passive smoking and highlight the need for stronger policies and interventions to minimize tobacco exposure. Addressing both active and passive smoking is critical to improving public health outcomes and reducing the burden of respiratory diseases such as COVID-19. Further research is essential to validate these findings and to inform evidence-based public health strategies.
Current activity concentrations of 226Ra, 232Th, 40K and 137Cs in beach sand samples from various coastal regions of Türkiye and associated health risk assessment
(Elsevier, 2026) Büyükuslu, Halim; Akçay, Nilay
In this study, gamma-spectrometry was used to determine the concentrations of 226Ra, 232Th, 40K, and 137Cs radioactivity in surface beach. Samples were collected from thirty-one coastal beaches across various cities in Türkiye. The results obtained were evaluated in the context of four geographical regions: Black Sea, Mediterranean, Marmara and Aegean. In all samples, the maximum, minimum, and mean activity concentration values were 66.06 ± 0.89, 1.07 ± 0.10, and 11.65 ± 0.39 Bq kg−1 for 226Ra; 43.04 ± 1.21, 0.76 ± 0.10, and 7.35 ± 0.41 Bq kg−1 for 232Th; and 657.39 ± 6.57, 27.54 ± 1.30, and 260.31 ± 4.06 Bq kg−1 for 40K, respectively. The maximum, minimum and mean activity concentration values of the anthropogenic 137Cs isotope were 6.53 ± 0.25, 0.3 ± 0.05 and 2.38 ± 0.17 Bq kg−1, respectively. The average values of radiological hazard indices such as equivalent radium activity, external(internal) hazard index, outdoor absorbed gamma dose rate and annual effective dose equivalent were calculated as 42.20 Bq kg−1, 0.11(0.15), 20.67 nGy h−1, 0.025 mSv y−1, for all samples respectively. The calculated radiological hazard indices were below the world averages and did not pose any significant health risk to beachgoers.
The role of the middle east in the biogeographical dispersal of host-specific parasites: monogeneans and their cyprinoid fish hosts
(John Wiley and Sons Inc, 2025) Nejat, F.; Benovics, M.; Šanda, R.; Vukić, J.; Kaya, Cüneyt; Tarkan, A.S.; Šimková, A.
Aim: This study investigates the diversity and phylogeny of Dactylogyrus species in the Middle East, as well as uncovers the historical dispersal routes and biogeographical contacts of cyprinoid host species using their host-specific parasites. Location: The Middle East. Taxon: Dactylogyrus (Dactylogyridae: Monogenea), Cyprinoidei (Cypriniformes). Methods: More than 1040 cyprinoid fish and their host-specific parasites were sampled in the Middle East. Phylogenetic analyses were conducted using the partial 18S rDNA, 28S rDNA, and complete ITS1 regions for the parasite species from the Middle Eastern species and those retrieved from GenBank, and the biogeographical analysis was performed. The mapping of the morphological characters of the attachment organ (haptor) onto the phylogeny was performed to reveal the patterns of morphological evolution and adaptation. Results: Phylogenetic analyses of Middle Eastern species and those retrieved from GenBank revealed seven major clades of Dactylogyrus parasites. Dactylogyrus species from the Middle East were present in five of these clades, alongside species from Europe, North Africa, and East Asia, emphasising the role of the Middle East, a crossroad of the historical dispersal of cyprinoids, in Dactylogyrus diversification. The deep nodal split of lineages suggests at least two independent dispersion events involving Dactylogyrus parasites from Asia to Europe and Africa. Additionally, mapping the morphological characters illustrated that the evolutionary patterns of haptor adaptation do not fully follow the evolutionary novelty.
Editorial: Does metabolic dysfunction-associated steatotic liver disease with advanced fibrosis also equate to risk of advanced coronary artery disease? Authors' reply
(John Wiley and Sons Inc, 2025) Zhou, Xiao-Dong; Yılmaz, Yusuf; Zheng, Ming-Hua
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