16 research outputs found
Assessment of the gate rudder system on the cavitation and underwater radiated noise characteristics of a containership
Predictions of model tests and numerical studies (Sasaki et al., 2016), both at model- and full-scale, as well as results of the recent sea trials, have demonstrated that the Gate Rudder System (GRS), a novel energy-saving device, increases propulsive efficiency and reduces fuel consumption of a ship. Despite detailed investigations into the impact of the GRS on powering performance and manoeuvring, studies on its effect on cavitation phenomena and underwater radiated noise (URN) are limited. In this study, the effects of the GRS on cavitation and URN were investigated experimentally and compared to a conventional rudder system (CRS). Cavitation observations and URN measurements were conducted on sister ships -one with the CRS, SAKURA, and the other with the GRS, SHIGENOBU- at Istanbul Technical University Cavitation Tunnel (ITUKAT). A wooden ship model was built to be used in resistance and propulsion tests and then truncated due to the cavitation tunnel's test section length limitation of 5.5 m. Numerical studies were performed for both the original and truncated models at model- and full-scale to assess their wake characteristics. The nominal wake distributions along the CRS and GRS propeller planes were measured using a Laser Doppler Velocimetry (LDV) system. The test results supported the findings of the sea trials, showing that the GRS significantly reduces URN levels by up to 10 dB at high-frequencies, compared to the CRS, due to its effect on propeller loading and cavitation phenomenon
Peroxisome proliferators-activated alpha agonist treatment ameliorates hepatic damage in rats with obstructive jaundice: an experimental study
<p>Abstract</p> <p>Background</p> <p>Peroxisome proliferators-activated receptor alpha (PPARα) activation modulates cholesterol metabolism and suppresses bile acid synthesis. This study aims to evaluate the effect of short-term administration of fenofibrate, a PPARα agonist, on proinflammatory cytokines, apoptosis, and hepatocellular damage in cholestasis.</p> <p>Methods</p> <p>Forty male Wistar rats were randomly divided into four groups: I = sham operated, II = bile duct ligation (BDL), III = BDL + vehicle (gum Arabic), IV = BDL + fenofibrate (100 mg/kg/day). All rats were sacrificed on 7<sup>th </sup>day after obtaining blood samples and liver tissue. Total bilirubin, aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP), gamma-glutamyl transferase, (GGT), tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1 β), and total bile acid (TBA) in serum, and liver damage scores; portal inflammation, necrosis, bile duct number, in liver tissue were evaluated. Apoptosis in liver was also assessed by immunohistochemical staining.</p> <p>Results</p> <p>Fenofibrate administration significantly reduced serum total bilirubin, AST, ALT, ALP, and GGT, TNF-α, IL-1 β levels, and TBA (<it>P </it>< 0.01). Hepatic portal inflammation, hepatic necrosis, number of the bile ducts and apoptosis in rats with BDL were more prominent than the sham-operated animals (<it>P </it>< 0.01). PPARα induction improved all histopathologic parameters (<it>P </it>< 0.01), except for the number of the bile duct, which was markedly increased by fenofibrate therapy (<it>P </it>< 0.01).</p> <p>Conclusion</p> <p>Short-term administration of fenofibrate to the BDL rats exerts beneficial effects on hepatocellular damage and apoptosis.</p
Akut üst gastrointestinal sistem kanamalarında acil panendoskopi
TEZ396Tez (uzmanlık) -- Çukurova Üniversitesi, Adana, 1987.Kaynakça (s. 65-73) var.73 s. ; 30 cm.
The impact of anorectal biofeedback therapy on the quality of life of patients with dyssynergic defecation.
Dyssynergic defecation is a common health problem affecting the quality of life of patients adversely. We aimed to evaluate the impact of biofeedback therapy on the quality of life of constipated patients due to dyssynergic defecation
The Adaptation of a Scale for Preschool Teachers' Attitudes Towards Science Teaching
This study was designed to adapt into Turkish the "Early Childhood Teachers' Attitudes towards Science Teaching Scale" developed by Hyung-Sook-Cho et al. (2003). The research data were collected from teachers, working with children at the age group of six in public or private nursery schools or nursery classes affiliated with the Ministry of National Education, in Ankara and Malatya, Turkey. For validity testing, factor analysis and item analysis were conducted; and for reliability testing, internal consistency and test-retest reliability methods were used. The findings of these tests demonstrate that the validity and reliability of the scale are at a sufficient level. (C) 2010 Elsevier Ltd. All rights reserved.WoSScopu
Pancreatic metastasis in a case of small cell lung carcinoma diagnosed by EUS.
Small-cell lung carcinoma represents a group of highly malignant tumors characterized by early and widespread metastais even at the time of diagnosis. However, the pancreas is a relatively infrequent site of metastasis by this neoplasm. A 57-year-old patient was admitted with an intense cough and complaints of abdominal discomfort. A chest X-Ray showed no evidence of lung mass but did show signs of lymphadenopathy. In addition, there was little evidence for malignancy based on a transbronchial needle aspiration. In contrast, there was a mass in the head portion of the pancreas. We diagnosed a case of small-cell lung carcinoma metastasis in the pancreas by using an endoscopic ultrasound-guided fine-needle aspiration biopsy. This case demonstrates that endoscopic ultrasound-guided fine-needle aspiration biopsy is an important tool in the diagnosis of metastatic pancreatic neoplasms
A novel triazine-bearing calix[4]arene: Design, synthesis and gas sensing affinity for volatile organic compounds
WOS: 000465052300008A novel triazine-calix[4]arene conjugate was designed and synthesized with the aim to study gas sensing against volatile organic compounds (VOCs) such as dichloromethane, chloroform and carbon tetrachloride. This novel compound was fully characterized by spectroscopic techniques such as FTIR,H-1 and C-13 NMR along with HRMS and BET analysis. The triazine based calix[4]arene organic materials were fabricated onto quartz glasses and quartz crystal substrates to form a thin film chemical sensor element by using Langmuir-Blodgett (LB) technique. Quartz Crystal Microbalance, UV-Visible Spectroscopy, Atomic Force Microscopy and Scanning Electron Microscopy techniques were employed to characterize all these LB thin film layers. Fick's Equations were used for analyzing the swelling process of LB thin film sensor and diffusion coefficient values of organic vapours for swelling were obtained. The initial experiments have revealed that new triazine appended calix[4]arene derivative exhibited an effective chemical gas sensor characteristic with a large response to dichloromethane vapour. (C) 2019 Elsevier Ltd. All rights reserved.Research Foundation of Usak UniversityUsak University [2018/MF002]The financial support from the Research Foundation of Usak University (Project No: 2018/MF002) is gratefully acknowledged. Additionally, we thank UBATAM (Usak University, Scientific Analysis Technological Application and Research Center) for analyses