• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.5
• /
• pp.901-907
• /
• 1997

The purpose of this study was to investigate the effects of green tea catechin o n free radical generation system and peroxidative damage in the liver of streptozotocin(STZ)-induced diabetic rats. Spragu-Dawley male rats weighing 150$\pm$10gm were randomly assigned to one normal and three STZ-induced diabetic groups; diabetic groups were classified to catechin free diet(DM-oC group), 0.5% catechin diet(DM-0.5C group) and 1% catechin diet(DM-1C group) according to the levels of dietary catechin supplementation. Diabetes was experimentally induced by intravenous injection of 55mg/kg of body wt of STZ in citrate buffer(pH 4.3) after feeding of three experimental diet for 4 weeks. Animals were sacrificed at the 6th day of diabetic states. Activities of serum glutamic oxaloacetic transaminase(GPT) in DM-oC groups were higher than those of the normal group, and those in catechin supplementation group were similar to those of the normal group. Liver lipid peroxide values increased by 153%, 49%, and 27% in Dm-oC, DM-0.5C and DM-0C and Dm-1C but was not significantly different in catechin supplementation groups compared with the normal group, and liver cytochrome $P_{450}$ contents was similar to result of XOD activity. In electron microscopic examination of liver, lysosome was relatively scattered in Dm-oC and Dm-0.5C group and preserved normal shapes in DM-1C group. The present results indicate that STZ-induced diabetic rats are more sensitive to oxidative stress, leading to the acceleration of lipid peroxidation process, but this was reduced by anti-oxidative effect of high level of dietary catechin. It is concluded that dietary catechin serves as powerful antioxidant against lipid peroxidation in diabetic rats.

• The Korean Journal of Pain
• /
• v.9 no.1
• /
• pp.46-56
• /
• 1996

Many surgeons and anesthesiologists prefer using vasoconstrictor mixed with local anesthetic agent to reduce the incidence of side effects and prolong the duration of analgesia because most local anesthetic agents, except cocaine, were believed to possess vasodilating effect. However, some investigators recently reported vasoconstricting effect of local anesthetic agents. There is still controversy on the vasoactive effect of local anesthetic agents. So this study is aimed to clarify the vasoactive effect of local anesthetics in the animal model resembling clinical settings. Rabbits were anesthesized with ketamine and haloghane, and respirations were controlled with Harvard animal ventilator. Lidocaine (0.5%, 1.0%, 1.5%) and bupivacaine (0.125%, 0.25% and 0.5%) with or without 1:100,000 epinephrine were subdermaly injected on the femoral bupivacaine of the femoral artery were measured with Doppler flow meter in vivo. The mean arterial pressure, pulse rate, arterial blood gases, pH and level of serum electrolytes were measured at every 2 minute interval for 30 minutes. Results were as follows: 1) There was no significant vasoconstriction with 0.5% lidocaine and 0.125% bupivacaine. 2) Statistically significant (p<0.05) vasodilations were observed with lidocaine (1.0~2.0%) and bupivacaine (0.25~0.5%). 3) There were no changes on the duration of vasodilation induced by local anesthetic agents of various concentrations. 4) Onset of vasodilation induced by local anesthetic agents of high concentration were faster than that of lower concentrations. 5) In the mixed injection group of epinephrine and local anesthetic agent, the vasoconstriction induced by epinephrine was completely reversed by local anesthetics, approximately 5 minutes later. In conclusion, local anesthetic agents at dose exceeding 1.0% lidocaine and 0.25% bupivacaine increase local blood flow significantly in animal study in vivo which is applicable in human clinical settings. The increase blood flow may be due to dilatation of blood vessel. Further study on the analysis of association between amount of absorbed local anesthetics in blood vessels and dilatation of blood vessels is needed.

• Food Science of Animal Resources
• /
• v.37 no.4
• /
• pp.561-570
• /
• 2017

This study examined the laxative effects of mulberry leaf extract (MLE) fermented by lactic acid bacteria (LAB), which contains high levels of polyphenolic and flavonoid compounds, against loperamide-induced constipation in rats. Sprague-Dawley rats were divided into a normal group (N) and three experimental groups; loperamide treated group (C), loperamide and LAB-fermented MLE 300 mg/kg treated group (MLEL), and loperamide and LAB-fermented MLE 600 mg/kg treated group (MLEH). After 33 d, fecal pellet amount, fecal weight, water content of fecal, gastrointestinal transit time and length, and serum lipid profiles were measured. Constipation was induced via subcutaneous injection of loperamide (2.0 mg/kg b. w., twice a day) for the final 5 d of the experiment. After loperamide administration, the LAB-fermented MLE groups showed a significantly increase in the fecal pellets number, wet weight, and water content in rats compared with the C group. Moreover, increases in the intestinal length and viable Lactobacillus numbers in the feces were observed in the LAB-fermented MLE groups. The intestinal transit time was shorter in the LAB-fermented MLE groups than in the C group. In addition, the LAB-fermented MLE groups showed a significant decrease in triglyceride and total cholesterol levels and an increase in HDL-cholesterol level. These results indicated that oral administration of LAB-fermented MLE shows laxative effect in loperamide-induced constipated rats.

• Korean Journal of Digital Imaging in Medicine
• /
• v.16 no.1
• /
• pp.27-33
• /
• 2014

The purpose of this study evaluated the hemo-dynamic information within 30 seconds clinically in 3D breast MRI. From January to March 2014, A total of 40 people were examined at 1.5 Tesla(Philips, Medical System, Achieva, The Netherlands) MRI equipments using 16 channel SENSE breast coil. The imaging parameters on vibrant are fellow as: $TR/TE/FA^{\circ}$/Matrix size/Slice thickness/Slab($5ms/2ms/10^{\circ}/180{\times}139{\times}2mm/80$). This study used a Gadovist and injected it with injection speed of 4 ml /sec by auto injector with 15 ml saline flushing. Firstly, for the delay time study, it divided three different delay time from immediately, 20 seconds, and 30 seconds. In quantitative analysis, the ROI signal intensities of tumor and surrounding tissues were measured retrospectively. In qualitative analysis, the image quality was scored from 1 to 5 point by one experienced radiological technologists as a visual test. The significance level of each delay time was evaluated with a one-way ANOVA(p<0.05). In the visual test, score levels on 30 seconds delay time was a little bit higher than others(p<0.05). The signal intensity of the tumor were $1445{\pm}360$, $1410{\pm}320$, $1510{\pm}415$ on immediately, 20 seconds, and 30 seconds and score levels were $4.18{\pm}0.85$, $3.54{\pm}0.94$, $4.45{\pm}0.74$(p<0.05). The data on immediate images showed better results than that others(p<0.05). Conclusively, Although it has been high scored in 30sec delay time for visual test in order to avoid failure in 20second, 30seconds delay time after contrast media administration, we recommend that the DCE 3D breast MRI commence immediately.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.17 no.1
• /
• pp.154-161
• /
• 2009

This study is a part of project of urea-SCR system development for an in-use medium duty diesel engine. This study shows the effect of ammonia oxidation catalyst and SCR volume on $NO_X$ reduction performance. When AOC(Ammonia Oxidation Catalyst) is not used, the urea injection should be controlled accurately to prevent $NH_3$ slip. However, it is found that the accurate $NH_3$ slip control is not easy without AOC in real engine operating conditions, because $NH_3$ and $NO_X$ reaction characteristics change with many factors such as exhaust gas temperature and $NH_3$ absorbance on SCR. SCR volume is also one of important design parameters. This study shows that $NO_X$ reduction efficiency increases with increase of SCR volume especially at high space velocity and low exhaust gas temperature conditions. Additionally, this paper shows the emissions of EURO-2 medium duty diesel engine can be improved to the level of EURO-5 with a DPF and urea-SCR system.

• Journal of Power Electronics
• /
• v.15 no.1
• /
• pp.146-159
• /
• 2015

Since the power capacity needed for the propulsion of large ships is very large, a multiphase AC induction propulsion mode is generally adopted to meet the higher requirements of reliability, redundancy and maintainability. This paper gives a detailed description of the development of a 20MW fifteen-phase PWM driver for advanced fifteen-phase propulsion induction motors with a special third-harmonic injection in terms of the main circuit hardware, control system design, experiments, etc. The adoption of the modular design method for the main circuit hardware design can make the enclosed mechanical structure simple and maintainable. It can also avoid the larger switch stresses caused by the multiple turn on of the IGBTs in conventional large-capacity converter systems. The use of the distributed controller design method based on a high-speed fiber-optic ring net for the control system can overcome such disadvantages as the poor reliability and long maintenance times arising from the conventional centralized controller which is designed according to point-to-point communication. Finally, the performance of the 20MW PWM driver is verified by experimentation on a new fifteen-phase induction propulsion motor.

• Archives of Plastic Surgery
• /
• v.38 no.4
• /
• pp.391-397
• /
• 2011

Purpose: The injection of various materials, including medical fillers and unregulated products, is widespread, potentially causing the development of foreign body granulomas. Should this occur on the nose, the contour deformity and inflammatory signs that result from these granulomas are aesthetically undesirable to patients. The purpose of our study is to share our experiences using different surgical approaches, depending on the affected portion of the nose, to optimize management of this challenging problem and to evaluate patient's satisfaction using our in-house questionnaire along with degree of improvement by two independent plastic surgeons. Methods: We treated 18 patients who underwent surgical excision of nasal foreign body granulomas via a perilesional approach to the lesion (n=12) or by transcolumellar incision (n=6) at our hospital over a period of seven years from March 2003 to October 2010. Nonparametric statistics were used and are presented as medians (25th-75th). Patient satisfaction was evaluated on a scale of 1 to 5 using an in-house questionnaire. All pre-and post-operative photographs were analyzed by two independent plastic surgeons. Post-operative outcomes were evaluated based on the surgeons' consensus ratings. Results: All patients receiving the transcolumellar approach reported a high level of satisfaction with the results. All but two patients who received the perilesional approach were satisfied with the outcome. No outcomes were rated as no change or worse by the consensus ratings. Conclusion: For the upper two-thirds of the nose, perilesional surgical excision can lead to substantial patient satisfaction with modified contour deformity and infection control. The transcolumellar approach resulted in better outcomes and patient satisfaction for the lower one-third of the nose.

• Journal of Korean Academy of Fundamentals of Nursing
• /
• v.13 no.1
• /
• pp.15-23
• /
• 2006

Purpose: This study was dont: to identify the differences nursing needs and satisfaction with medications in patients admitted to hospital. Method: The participants were 258 patients admitted for 3days or more to D hospital. The data were analyzed using frequencies, percentages, means, standard deviations, t-test and ANOVA. SPSS-WIN 11.0 was used to assist analysis. Results: The results are as follow: 1. Variables effecting nursing needs were education and economic level. All scores of nursing needs were higher in the group with less than middle school education compared to those with high school education or higher. 2. The scores for nursing needs were higher than the score for satisfaction in common item and injection domains. The scores for nursing satisfaction were higher than nursing needs in the oral medication domain. 3. The item with the highest difference between the scores for nursing needs and satisfaction was 'I want to know the side effect of the drugs'. Conclusion: Patients admitted to hospital want to know the therapeutic effect, side effect and reason for their drugs. However satisfaction with medication was not equal to needs. It is necessary to emphasize clinical pharmacology in nursing education programs.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.14 no.5
• /
• pp.853-862
• /
• 2019

In this paper, we designed a 4.5kW X-band SSPA transmitter to replace the TWTA search radar transmitter with low MTBF and high maintenance cost. The transmitter is designed for the performance of over 520W average transmission output and 4.0kW maximum transmission output. In particular, by implementing a graceful degradation, it is designed to maintain better performance than conventional TWTA transmitter up to 40% (13 assembly modules) failure level of 200W power amplifier assembly. Through an experiment on the effective range of X-band, the performance of proposed transmitter verified the values of the maximum transmission output 6.1kW, spurious output 69.16dBc, RF pulse rising time 15.2ns and RF pulse falling time 16.3ns. The experiment confirmed the change of output power according to the graceful degradation due to fault injection.

• Journal of Navigation and Port Research
• /
• v.43 no.2
• /
• pp.79-85
• /
• 2019

Climate change is a very vital issue that can be no longer avoided. Korea has been a top-level country Iin dealing with carbon dioxide emissions since 1960. Many studies have been conducted to suppress or eliminate carbon dioxide emissions, which account for a large portion of greenhouse gases. Carbon Capture and Storage (CCS), the most practical method of them, plays a significant role. However, these methods have the disadvantage of the limits of geographical distribution and high possibility of re-emission into the atmosphere. Recently, ocean storage has been studied using Accelerated Weathering of Limestone (AWL), a technique for storing carbon dioxide in the ocean as an alternative to CCS, an underground storage. AWL is a method of converting carbon dioxide into concentrated water in the form of bicarbonate ion and discharging it to the ocean to dilute and store it. It does not cause re-emission to the atmosphere, and the discharged concentrated water increases the alkalinity of the ocean to prevent marine acidification. The objective of this study was to understand the behavior of DIC (Dissolved Inorganic Carbon) including carbon dioxide during the ocean discharge of bicarbonate ion concentrated water in AWL method. This study area was set near Ulleung-do where sufficient water depth and operational efficiency were secured. CORMIX model was used to calculate the material diffusion by submerged discharge using ship.