Yazar "Ergun H." seçeneğine göre listele

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    Analysis of partially embedded beams in two-parameter foundation
    (Techno Press, 2012) Akoz A.Y.; Ergun H.
    In this study, Pasternak foundation model, which is a two parameter foundation model, is used to analyze the behavior of laterally loaded beams embedded in semi-infinite media. Total potential energy variation of the system is written to formulate the problem that yielded the required field equations and the boundary conditions. Shear force discontinuities are exposed within the boundary conditions by variational method and are validated by photo elastic experiments. Exact solution of the deflection of the beam is obtained. Both foundation parameters are obtained by self calibration for this particular problem and loading type in this study. It is shown that, like the first parameter k, the second foundation parameter G also depends not only on the material type but also on the geometry and the loading type of the system. On the other hand, surface deflection of the semi infinite media under singular loading is obtained and another method is proposed to determine the foundation parameters using the solution of this problem. Copyright © 2012 Techno Press.
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    The effect of the iNOS inhibitor S-methylisothiourea and hyperbaric oxygen treatment on radiation colitis in rats
    (Universa Press, 2016) Demirci H.; Polat Z.; Uygun A.; Kadayifci A.; Sager O.; Ozturk K.; Kantarcioglu M.; Sahiner F.; Caliskan B.; Karslioglu Y.; Ozler M.; Ozel M.; Ergun H.; Ozturk O.; Beyzadeoglu M.; Bagci S.
    Introduction: External radiotherapy is one of the main treatment modalities for a variety of malignancies. However, the lower gastrointestinal tract is sensitive to the ionizing radiation. Hyperbaric oxygen treatment (HOT) has been suggested as a viable treatment for refractory radiation colitis, but the effect of S-Methylisothiourea (SMT) in the radiation colitis have not reported. Aim: To investigate the effect of SMT, HOT and the combination of both in an acute radiation-induced enterocolitis model. Methods: Sixty Sprague-Dawley rats were divided randomly into five equal groups. A single dose of gamma irradiation (25 Gy) was administered through the colorectal region to anesthetized rats. In the control group, we applied 2 ml of saline solution intraperitoneally for five days. In the HOT group, 100-per-cent oxygen at 2.5 atm pressure was applied for five days. In the SMT group, 10 mg/kg/day of SMT was applied intraperitoneally for five days. In the HOT+SMT group, HOT and SMT were both applied in the same dosages as in the preceding two groups. At the end of five days, the rats were sacrificed and colon samples were collected for histological grading. Blood samples were collected to test for: tumor necrosis factor-? (TNF-?), interleukin-10 (IL-10), IL-1ß, transforming growth factor-ß (TGF-ß) and intercellular adhesion molecule-1 (ICAM-1) mRNA. Results: The TNF-?, IL-1ß, IL-10 and TGF-ß levels were reduced by SMT, HOT and HOT+SMT applications (p < 0.05). However ICAM-1 mRNA levels were not significantly lower (p:0.19). The microscopic scores differed significantly between the SMT, HOT and HOT+SMT groups and the control group. There was significant improvement histologically, especially in the HOT+SMT group. When we compared the weight of the rats before and after the study, weight loss was significantly lower in the SMT, HOT and HOT+SMT groups compared with the control group (p < 0.05). Conclusions: HOT and SMT together were significantly more effective in preventing weight loss and in reducing inflammation and the severity of colitis histology when compared with HOT and SMT separately. (Acta gastro enterol. belg., 2015, 78, 8-13). © 2016, Universa Press. All rights reserved.