• Clinical and Experimental Reproductive Medicine
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• v.26 no.2
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• pp.149-156
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• 1999

Steroid hormone is known to cause the dynamic changes of mammalian uterus during reproductive cycle, which are modulated via hypothalamus-pituitary -gonad reproductive endocrine axis. Although there were so many studies about estrogenic regulation of uterine growth and differentiation. There is little information about the effect of estrogen on the expression of various transcription factors involved in gene expression. Thus the present study was designed to demonstrate E induced expression of c-fos, c-jun, hsp25 mRNA in rat uterus. Employing Northern blot analysis, we studied the temporal expressions of c-fos, c-jun, and hsp25 messenger RNAs (mRNAs) elicited by a single 17beta-estradiol (E) treatment in the uteri of bilaterally ovariectomized adult rats. c-fos, c-jun, and hsp25 mRNA levels were increased and peaked at 3h after E administration, and then c-fos and c-jun mRNA levels were rapidly decreased to basal control level while, increased hsp25 mRNA levels were sustained till 12h post E treatment. To test the estrogenic effect on the increase of c-fos, c-jun, and hsp25 mRNA levels, we also examined the effects of antiestrogen (tamoxifen). Pretreatment with tamoxifen effectively blocked the E-induced increase of c-fos, c-jun, and hsp25 mRNA levels at 3h post E treatment. Present results suggest that transient increase of c-fos and c-jun protooncogene mRNA at the early time and simultaneous expression of hsp25 mRNA contribute to the response of uterine tissues to E in adult female rats.

• Fire Science and Engineering
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• v.20 no.3 s.63
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• pp.65-70
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• 2006

From the beginning of the construction stage, the fire protection regulation for the nuclear power plants conforms to the design requirements for the acquisition of the license permit. This regulation is based on the plant status of the normal operation, but it is not enough to be used as an application standard for fire protection at the transient mode of the plant and the outage time for refueling as well as for the plant decommissioning. While the advanced fire protection requirement that has been developed in America recently suggests the performance-based requirement and management rule applicable to the overall life time of the plant, it simply represents the conceptual application. It means that it can not be treated as appropriate standards because it does not deal with the qualitative and quantitative approach in specific ways. By the way, with the use of the performance-based fire risk analysis, the dynamic behavior of the heat and smoke at the fire compartment of the nuclear power plants can be analyzed and the thermal effect to the safety-related equipment and cables can be evaluated as well. At this paper, it suggests the ways to change the applicable fire protection regulations and the required evaluation items for the fire risk resulted from the plant configuration change with an intent to introduce the state-of-the-art quantitative fire risk analysis technology at the domestic nuclear power plants.

• The Journal of Korean Medicine
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• v.18 no.2
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• pp.223-244
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• 1997

Clinical observation was done on 290 cases of patients who were diagnosed as CVA with brain CT, TCD, MRI scan and clinical observation. They were hospitalized in the oriental medical hospital of Kyung-Won University from 1st January to 31st December in 1996. 1. The cases were classified into the following kinds : cerebral infarction, cerebral hemorrhage, and transient ischemic attack. The most case of them was the cerebr진 infarction. 2. There is no significant difference in the frequency of strokes in male and female. And the frequency of strokes was highest in the aged over 50. 3. In cerebral infarction the most frequent lesion was the territory of middle cerebral artery, and in cerebral hemorrhage the most frequent lesion was the basal ganglia. 4. The most ordinary preceding disease was hypertension, and the next was diabetes. 5. The rate of recurrence was high in cerebral infarction. 6. The frequency of strokes seems to have no relation to the season. 7. The cerebral infarction occurred usually in resting and sleeping, and the cerebral hemorrhage in acting. 8. The course of entering hospital, most patients visited this hospital as soon as CVA occurred. And the half of patient visited this hospital within 2 days after CVA attack. 9. In the cases of patients who were unconscious at the admission, the prognosis was worse than that of the alert patients. 10. The common symptoms were motor disability and verbal disturbance. 11. The average duration of hospitalization was 27.4 days, and in case of cerebral hemorrhage the duration was prolonged. 12. The average time to start physical therapy was 13.3rd day after stroke in cerebral infarction and it was 19.9th day after stroke in cerebral hemorrhage. 13. The common complications were urinary tract infection, pneumonia, myocardial infarction and so on. 15. At the time of entering hospital, in most cases the blood pressure was high, but blood pressure was well controlled at the time of discharge. 16. Generally reported, hypercholesterolemia and hypertriglyceridemia are usually found in cerebral infarction. But in this study, they were found more frequently in cerebral hemorrhage than in infarction. 17, In the most cases, western and oriental medical treatments were given simultaneously. 18. In acute or subacute stage, the methods of smoothening the flow of KI(順氣), dispelling phlegm(祛痰), clearing away heat(淸熱) or purgation(瀉下) were frequently used. And in recovering stage, the methods of replenishing KI(補氣), tonifying the blood(補血) or tranquilization(安神) were frequently used.

• The Journal of Korean Medicine
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• v.23 no.4
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• pp.161-168
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• 2002

Objectives: Hwangryunhaedok-tang (Huang-lian-jie-du-tang, HRHDT, 黃連解毒湯) is a traditional Korean herbal medicine that is formulated with Coptidis Rhizoma, Phellodendri Cortex, Scutellariae Radix and Gardeniae Fructus. HRHDT is cold (寒) and bitter (苦) in nature and has general properties of clearing heat and detoxifying (淸熱解毒), strengthening the stomach and settling the liver (健胃平肝), and reducing inflammation, fever and swelling. This formula can prevent and treat artherosclerosis, hyperplasia of the endothelium, cerebral fluid circulation, cerebral vascular deterioration through aging, impairment of neurotransmitters, or disruption of the functioning of the cerebral cortex following infection or trauma. The purpose of the study reported here was to determine the neuroprotective effect of HRHDT on global ischemia induced by 4-vessel occlusion in Wistar rats. Methods: HRHDT extract was lyophilized after extraction with 85% methanol and 100% water. Rats were induced to 10 minutes of forebrain ischemia by 4-vessel occlusion (4-VO) and reperfused again. HRHDT was administered with a dose of 100 mg/kg, and 500 mg/kg of 85% methanol extracts and 100 mg/kg of 100% water extracts, respectively, at 0 min and 90 min after 4-VO. Rats were killed at 7 days after ischemia and the number of CA1 pyramidal neurons was counted in hippocampal sections stained with cresyl violet. Results: Body temperature of animals showed no significant difference between saline-treated groups and HRHDT extracts-treated groups until 5 hours of reperfusion. This result indicated that neuroprotective effects of HRHDT extracts were not due to hypothermic effects. The administration of HRHDT showed a significant neuroprotective effect on hippocampal CA1 neurons at 7 days after ischemia compared to the saline-treated group (P<0.001). HRHDT methanol extracts of 100 mg/kg, 500 mg/kg and HRHDT water extracts of 100 mg/kg showed 88.5%, 98.3% and 95.1 % neuroprotection, respectively. Conclusions: The results of this study demonstrate that administration of HRHDT is highly effective in reducing neuronal damage in response to transient global cerebral ischemia. HRHDT may involve many mechanisms that might account for its high degree of efficacy. A number of factors including free radicals, glutamate, calcium overload, NO, and various cytokines have been proposed to have an important role in causing neuronal death after short periods of global ischemia. Further studies are needed to know the neuroprotective mechanisms of HRHDT.

• The Korea Journal of Herbology
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• v.32 no.1
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• pp.25-31
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• 2017

Objectives : Mori Radicis Cortex (MRC), the root epidermis of Morus alba L., has been traditionally used to treat lung-related diseases in Korean Medicine. The common of MRC is Mulberry bark Morus bark, and it's pharmaceutical properties and taste are known as sweet and cold, and it promotes urination and reduce edema by reducing heat from the lungs and soothe asthma. In the present study, anti-apoptotic mechanism of MRC in middle cerebral artery occlusion (MCAO) model in mice. Methods : Two-hundred grams of MRC was extracted with methanol at room temperature for 5 days, and this was repeated one time. After filtration, the methanol was removed using vacuum evaporator, then stored at $-20^{\circ}C$ until use. C57BL/6 male mice were housed in an environment with controlled humidity, temperature, and light cycle. In order to determine beneficial effects of MRC on ischemia induced brain damage, infarct volume, neurological deficit scores, activities of several apoptosis-related proteins such as caspase-8, -9, Bcl-xL in MCAO-induced brains of mice were analyzed. Mice in MRC-treated groups were orally administered 30, 100, or 300 mg/kg of body weight for three consecutive days before commencing the MCAO procedure. Results : Pre-treatment of MRC significantly reduced infarct volume in MCAO subjected mice applied with 300 mg/kg of MRC methanol extract, and MRC effectively inhibited Bcl-xL reduction and caspase-9 activation caused by MCAO-induced brain damage. Conclusions : MRC showed neuro-protective effects by regulating apoptosis-related protein signals, and it can be a potential candidate for the therapy of ischemia-induced brain damage.

• Journal of the Korean Institute of Gas
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• v.20 no.6
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• pp.23-30
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• 2016

The conventional natural gas engine realized lean combustion for the improved efficiency. However, in order to cope with exhaust gas regulations enforced gradually, the interest has shifted at the stoichiometric mixture combustion system. The stoichiometric mixture combustion method has the advantage of a three-way catalyst utilization whose purification efficiency is high, but the problem of thermal durability and the fuel economy remains as a challenge. Hydrogen-natural gas blend fuel (HCNG) can increase the rate of exhaust gas recirculation (EGR) because the hydrogen increases burning speed and lean flammability limit. The increase in the EGR rate can have a positive impact on heat resistance of the engine due to the decreased combustion temperature, and further can increase the compression ratio for efficient combustion. In this study, to minimize the exhaust emission developed HCNG engine with stoichiometric combustion method, developed three-way catalyst was applied to evaluate the conversion characteristics. The tests were carried out during the steady state and transient operating conditions, and the results were compared for both the conventional and proto-three-way catalyst of HCNG engine for city buses.

• Nuclear Engineering and Technology
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• v.27 no.4
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• pp.470-482
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• 1995

The Ulchin 3&4, which are 2825 MWt PWRs, adopted Safety Depressurization System (SDS) to mitigate the beyond design basis event of Total Less of Feedwater(TLOFW). In this study the results and methodology of the analyses for the determination of SDS bleed capacity are discussed. The SDS design bleed capacity has been determined from the CEFLASH-4AS/REM simulation according to the following design criteria : 1) Each SDS flow path, in conjunction with one of two High Pressure Safety Injection (HPSI) pumps, is designed to have a sufficient capacity to prevent core uncovery if one SDS path is opened simultaneously with the opening of the Pressurizer Safety Valves (PSVs). 2) Both SDS bleed paths are designed to have sufficient total capacity with both HPSI pumps operating to prevent core uncovery if the Feed and Bleed (F&B) initiation is delayed up to thirty minutes from the time of the PSVs lift. To verify the results of CEFLASH-4AS/REM simulation a comparative analysis kas also been per-formed by more sophisticated computer code, RELAP5/MOD3. The TLOFW event without operator recovery and TLOFW event with F&B are analyzed. The predictions by the CEFLASH-4AS/REM of the transient too phase system behavior are in good qualitative and quantitative agreement with those by the RELAP5/MOD3 simulation. Both of the results of analyses by CEFLASH-4AS/REM and RELAP5/MOD3 have demonstrated that decay heat removal and core inventory make-up can be successfully accomplished by F&B operation during now event for the Ulchin 3&4.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.97-107
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• 2020

In this study, finite element analysis was carried out through the finite element analysis program (ANSYS) to investigate the fire resistance of composite columns in fire. Transient heat transfer analysis and static structural analysis were performed according to ASTM E 119 heating curve and axial force ratio 0.7, 0.6, 0.5 by applying stress-strain curves according to temperature, and loading heating experiments were carried out under the same conditions. In addition, the nominal compressive strength of the composite column according to the heating time according to the standard(Eurocode 4) was calculated and expressed as the axial force ratio and compared with the analytical and experimental values. Through the analysis, As a result of finite element analysis, the fire resistance time was 180 minutes and similar value to the experimental value was obtained, whereas the fire resistance time 150 minutes and 60 minutes were derived from the axial force ratios 0.6 and 0.7. In addition, it was confirmed that the fire resistance time according to the axial force ratio calculated according to the reference equation (Eurocode 4) was lower than the actual experimental value. However, it was confirmed that the standard(Eurocode 4) was higher than the experimental value at the axial force ratio of 0.7. Accordingly, it is possible to confirm the fire resistance characteristics(time-axial force ratio relationship) of the SRC column at high axial force, and to use the experimental and anaylsis data of the SRC column as the data for verification based on Eurocode.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.377-386
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• 2021

The A60 class deck penetration piece is a fire-resistant system installed on a horizontal compartment to prevent flame spreading and protect lives in fire accidents in ships and offshore plants. This study deals with approximate optimization using discrete variables for the fire resistance design of an A60 class deck penetration piece using different surrogate models and a genetic algorithm. Transient heat transfer analysis was performed to evaluate the fire resistance design of the A60 class deck penetration piece. For the approximate optimization of the piece, the length, diameter, material type, and insulation density were applied to discrete design variables, and temperature, productivity, and cost constraints were considered. The approximate optimum design problem based on the surrogate models was formulated such that the discrete design variables were determined by minimizing the weight of the piece subjected to the constraints. The surrogate models used in the approximate optimization were the response surface model, Kriging model, and radial basis function-based neural network. The approximate optimization results were compared with the actual analysis results in terms of approximate accuracy. The radial basis function-based neural network showed the most accurate optimum design results for the fire resistance design of the A60 class deck penetration piece.

• The Korean Journal of Pharmacology
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• v.32 no.3
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• pp.335-345
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• 1996

A critical role of oxygen-derived free radicals has been implicated in ischemia/reperfusion (I/R)-induced brain damage. In this study, we have produced experimental I/R to the brains of Mongolian gerbil (Meriones unguiculatus) by a transient occlusion and release of the common carotid arteries. We have attempted to determine whether the oxidative stress is generated upon I/R and whether this oxidative stress is linked to the cell damage. Since hippocampus has been suggested as one of the most vulnerable regions of the brain to the oxidative stress, we analyzed samples from hippocampus in comparison with those from cortex. In addition, we have examined the expression of heat shock protein 70kD species (HSP70) in these regions in order to evaluate a possible role of this protein in I/R-induced brain damage. To determine whether the oxidative stress is produced upon I/R, we measured the glutathione oxidation, GSSG/ (GSH + 2xGSSG), as an index of oxidative stress. We found an increase of the glutathione oxidation primarily in hippocampus upon I/R. To determine whether this oxidative stress is linked to the cell damage, we measured the degree of lipid peroxidation upon I/R. We found an increase of lipid peroxidation in both regions. However, the magnitude of increases was greater in hippocampus than in cortex. In addition, we found that changes in both the magnitude and the temporal patterns of glutathione oxidation closely correlated with those of lipid peroxidation. Our study provides biochemical evidences that the oxidative stress is generated upon I/R and this oxidative stress is linked to the oxidative cell damage. Our study also provides evidences that the degree of oxidative stress as well as oxidative cell damage is greater in hippocampus than in cortex. We could not find difference in the basal level of HSP70 expression between hippocampus and cortex, indicating that the intrinsic vulnerability of hippocampus cannot be explained by the lower level of HSP70 expression. We did find, however, that the induction of HSP70 expression upon I/R was impaired in the hippocampus. This impairment appeared to be at the transcriptional level. These results suggest that the measurement of HSP70 induction may be employed as a useful predictor of differential cellular susceptibilities to the I/R-induced brain damage.