• YAKHAK HOEJI
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• v.45 no.5
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• pp.513-521
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• 2001

The chronic cholestasis induce to biliary liver fibrosis (cirrhosis) and the increased products of ROS(reactive oxygen species) cause to the liver damage. In this study ; the antioxidant and antifibrotic effect of dried extracts of oriental medicine (DW) was investigated under the liver fibrotic (cirrhotic) condition. The female Sprague-Dawley rats were divided in 5 groups (Normal, Op-2, Op-4, OpDW-2, OpDW-4). Except for normal group, the rats were induced to biliary liver fibrosis (cirrhosis) by the operation of bile duct ligation/scission (BDU/S) and were observed in 2 weeks or 4 weeks. And the prepared DW was treated p.o.2 ml/day/rats in 2 weeks or 4 weeks for OpDW groups. At the time of sacrifice, the liver, kidney, spleen were weighed and the ratio of organ weight/body weight was calculated. The MDA, the hyp and biochemical parameters (GOT GTP, ALP, t-bili) were measured in sera and liver tissue of rats. The biochemical change was observed on liver tissue. In the result, the hepatomegaly and spleenomegaly appeared in all BDL/S operated rats, and significantly lower liver weight was observed in OpDW-4 group compared with in Op-4 group (p<0.05). The level of clinical parameters in sera of all liver fibrosis (cirrhosis) developed rats was higher than in normal group. Especial1y, the value of GOT in OpDW-2 group and ALP in OpDW-4 group showed significantly lower than in Op-2 group and Op-4 group (p<0.01, p<0.005). The content of hyp in all operation groups was significantly higher than in normal group (p<0.05∼<0.005), and showed significantly lower value in the OpDW-4 group than in Op-4 group (p<0.05). The product of lipid peroxidationUDA) increased significantly under the fibrotic(cirrhotic) condition (p<0.05∼ <0.005), and the MDA value in OpDW-4 group decreased significantly in Op-4 group (p<0.005). The histological change (bile duct proliferation, fibrosis, collagen bundle) was similarly observed in Op-2 group and in OpDW-2 group, but the weak fibrosis and bile duct proliferation were observed in OpDW-4 group compared with in Op-4 group. In conclusion, lipid peroxidation and severe liver damage were activated by bile duct obstruction, and the measurement of MDA and hap can be useful monitor for the screening of antioxidant and antifibrotic effect in experimental liver fibrosis (cirrhosis). The 4 weeks treatment with DW extracts suppressed lipid peroxidation and inhibited fibrotic (cirrhotic) process in BDL/S operated rats.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.12
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• pp.815-824
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• 2016

The fuel assembly for pressurized water reactor (PWR) consists of fuel rod bundle, spacer grid and bottom/top end fittings. The cooling water in high pressure and temperature is introduced in lower plenum of reactor core and directed to upper plenum through the subchannel which is formed between the fuel rods. The main thermal-hydraulic performance parameters for the PWR fuel are pressure drop and critical heat flux in normal operating condition, and quenching time in accident condition. The Korea Atomic Energy Research Institute (KAERI) has been developing an advanced PWR fuel, dual-cooled annular fuel and accident tolerant fuel for the enhancement of fuel performance and the localization. For the key thermal-hydraulic technology development of PWR fuel, the KAERI LWR fuel team has conducted the experiments for pressure drop, turbulent flow mixing and heat transfer, critical heat flux(CHF) and quenching. The computational fluid dynamics (CFD) analysis was also performed to predict flow and heat transfer in fuel assembly including the spent fuel assembly in dry cask for interim repository. In addition, the research cooperation with university and nuclear fuel company was also carried out to develop a basic thermal-hydraulic technology and the commercialization.

• Nuclear Engineering and Technology
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• v.26 no.3
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• pp.440-452
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• 1994

Nuclear fuel bundles are designed such that the heat flux at a-fuel pin surface should not exceed the critical heat flux (CHF) during normal operation and anticipated transient. Therefore, evaluation of the CHF for fuel bundle is demanded in an exact and reliable manner. One of the major concerns with the current application of CHF correlations is that the CHF based on circular tubes is applied to the fuel bundle subchannel analysis, mainly in terms of the hydraulic diameter with correction factors which may result in a source of possibly large uncertainties in CHF prediction. The hydraulic diameter does not recognize the local properties of fluid nor such effect as the surface curvature; the turbulence action on the convex surface is much more pronounced than that on the concave surface. Even for the tube having concave curvature, the effect of tube diameter on CHF becomes important with decreasing diameter. These facts imply that the convex curvature effect is significant and crucial to the reliable CHF prediction. This paper reviews and discusses analytical and experimental aspects of effect of transverse convex curvature in incompressible turbulent flow and heat transfer, and on CHF. Flow models to quantify this effect are briefly mentioned and future works are recommended.

• Journal of the Korean Society for Library and Information Science
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• v.45 no.2
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• pp.209-228
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• 2011

Web search behavior has evolved. People now search using many diverse information devices in various situations. To monitor these scattered and shifting search patterns, an improved way of learning and analysis are needed. Traditional web search studies relied on the server transaction logs and single query instance analysis. Since people use multiple smart devices and their searching occurs intermittently through a day, a bundled query research could look at the whole context as well as penetrating search needs. To observe and analyze bundled queries, we developed a proprietary research software set including a log catcher, query bundling tool, and bundle monitoring tool. In this system, users' daily search logs are sent to our analytic server, every night the users need to log on our bundling tool to package his/her queries, a built in web survey collects additional data, and our researcher performs deep interviews on a weekly basis. Out of 90 participants in the study, it was found that a normal user generates on average 4.75 query bundles a day, and each bundle contains 2.75 queries. Query bundles were categorized by; Query refinement vs. Topic refinement and 9 different sub-categories.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1996.10b
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• pp.18-28
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• 1996

The outer-most electrons of metal atoms and the remaining valence electrons of any molecular atoms make three-dimensional crystallizing $\pi$-bondings. The rotating electrons on the three-dimensional crystallizing $\pi$-bonding orbitals of atoms make $\pi$-far infrared rays. Longitudinal wave is a propagation of a bundle of $\pi$-far infrared rays, which are produced by a dynamic impact on a solid bar. The $\pi$-far infrared rays make three-dimensional crystallizing $\pi$-bondings in the material, which reproduce the same $\pi$-far infrared rays. If a current signal is input into water molecules under a given electric potential field with $\pi$-far infrared rays (input information), the signal can be amplified because the $\pi$-far infrared rays make the $\pi$-bondings, which reduce electric resistance. The three-dimensional crystallizing $\pi$-bondings can induce normal electrons to move from one orbital to next one with a aid of potential electric field. Quantum Resonance Spectrometer is composed of tesla coil absorbing $\pi$-far infrared rays, tesla coil emitting varying electromagnetic waves signal generator, signal storage, human body amplifier, signal analyzer and data indicator. The absorbing tesla coil making varying magnetic field and downward and upward electric field, which resonates the $\pi$-far infrared rays coming out from specimen and absorbs them. The modulated current signal from the input square signal can generate and emit varying electromagnetic waves from the tesla coil. The varying electro-magnetic waves make the three-dimensional crystallizing $\pi$-bondings and the $\pi$-far infrared rays in the water molecules.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2283-2287
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• 2007

Amyloid fibril formation of amyloid β/A4 protein (Aβ) is critical to understand the pathological mechanism of Alzheimer's disease and develop controlling strategy toward the neurodegenerative disease. For this purpose, dequalinium (DQ) has been employed as a specific modifier for Aβ aggregation and its subsequent cytotoxicity. In the presence of DQ, the final thioflavin-T binding fluorescence of Aβ aggregates decreased significantly. It was the altered morphology of Aβ aggregates in a form of the bundles of the fibrils, distinctive from normal single-stranded amyloid fibrils, and the resulting reduced β-sheet content that were responsible for the decreased fluorescence. The morphological transition of Aβ aggregates assessed with atomic force microscope indicated that the bundle structure observed with DQ appeared to be resulted from the initial multimeric seed structure rather than lateral association of preformed single-stranded fibrils. Investigation of the seeding effect of the DQ-induced Aβ aggregates clearly demonstrated that the seed structure has determined the final morphology of Aβ aggregates as well as the aggregative kinetics by shortening the lag phase. In addition, the cytotoxicity was also varied depending on the final morphology of the aggregates. Taken together, DQ has been considered to be a useful chemical probe to control the cytotoxicity of the amyloid fibrils by influencing the seed structures which turned out to be central to develop therapeutic strategy by inducing the amyloid fibrils in different shapes with varied toxicities.

• Korean Journal of Veterinary Research
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• v.45 no.3
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• pp.369-373
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• 2005

A male mixed breed dog with unknown age (case 1) and 5-year-old female golden retriever (case 2) were admitted to the Department of Veterinary Pathology at College of Veterinary Medicine, Seoul National University after sudden death. At necropsy, stifle region of case 1 was replaced by coalescing firm tan nodules approximately 1-3 cm in diameter. Neoplastic nodules were also presented in the lung. In case 2, the spleen was enlarged 3-5 times its normal size and numerous firm tan nodules were noted in the kidney, pericardium, diaphragm and lymph nodes. Histopathologically, the neoplastic masses of case 1 consisted of plump spindle cells having abundant cytoplasm and indistinct cell borders that formed interlacing bundle. In case 2, the masses were consisted of round to polygonal cells with abundant eosinophilic cytoplasm and eccentric nuclei. Numerous multinucleated giant cells containing nuclei of various sizes were noted. Immunohistochemically, neoplastic cells of all two cases stained intensely with vimentin and lysozyme. Based on the gross and light microscopic findings together with immunohistochemistry, both cases were diagnosed as localized histiocytic sarcoma with pulmonary metastasis and disseminated histiocytic sarcoma, respectively.

• Journal of The Korean Society of Clinical Toxicology
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• v.2 no.1
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• pp.7-11
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• 2004

Purpose: We would evaluate the cardiovascular manifestations of the patients with acute organophosphate and carbamate poisoning in the emergency department. Methods: This was retrospectively studied with the review of patient's charts, included total 38 patients were admitted during the past two years in the emergency department of Yeungnam university hospital with the diagnosis of organophosphate or carbamate poisoning. Results: Cardiovascular complications were variously developed in many patients. Electrocardiographic findings were as follows; 4 ($10.5\%$) cardiac arrhythmias included 1 cardiac arrest caused by ventricular fibrillation, 14 ($36.8\%$) sinus tachycardias, 3 ($7.9\%$) sinus bradycardias, and 17 ($44.7\%$) normal sinus rhythms. Conduction disturbances were 23 ($60.5\%$) like as prolonged QTc, 4 ($10.5\%$) ST-T changes, 2 (5.3%) first degree AV block, and 3 ($7.9\%$) right bundle branch block were shown. Other cardiovascular complications were 22 ($57.9\%$) hypertensives, 4 ($10.5\%$) hypotensives, 15 ($39.5\%$) tachycardias, 2 ($5.3\%$) bradycardias, 18 ($47.4\%$) hypoxemics, 12 ($31.6\%$) metabolic acidosis, and 9 ($23.7\%$) pulmonary edemas. Sixteen patients ($42.1\%$) needed ventilatory support because of respiratory paralysis. No patients died in hospital and 36 ($94.7\%$) patients were alive-discharged. Conclusion: Cardiovascular complications are variously in patients with acute organophosphate and carbamate poisoning. Especially, some findings included ventricular arrhythmias, QTc prolongation, hypoxemia, acidosis, and blood pressure changes are known as major precipitating factors to increase the mortality. So, intensive support and aggressive treatment are needed in patients shown various cardiovascular manifestations in the emergency department.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.167-172
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• 1986

This experiment was carried out to obtain some information about the growth habit and morphological and anatomical characteristics of fasciated soybean, var. Buchai-kong. The results obtained are summarized as follows: 1. Main stern of fasciated soybean, var. Buchai-kong was gradually broadened and became flat, on which leaves emerged irregularly compared with normal soybean, var. Danyeop-kong. The number of leaves on main stern was more in Buchai-kong, but the total number of leaves per plant was not considerably different each other. 2. The degree of fasciation (max./min. in diameter at the broadened part) in main stern of Buchai-kong was about 3.1, and was related to the amount of growth of main stern and branches of Danyeop-kong. Stern fasciation types found in Buchai-kong were linear (the most common) and bifurcated with regard to branching of main stern tip. 3. The number of branches per plant was much less in Buchai-kong than in Danyeop-kong. There were fas-ciated branches and fasciated petiole in Buchai-kong. 4. About 75 percent of pods of Buchai-kong were concentrated on the top of stern, which showed strong pod clustering. 5. Seed yield per plant of Buchai-kong was about 60 percent of that of Danyeop-kong, and the decrease in seed yield was mostly affected by the decrease in seed weight and seeds per pod. 6. The number of vascular bundles of transection of mature stern was more in Buchai-kong, but Danyeop-kong developed the better vascular bundle.

• Plant Journal
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• v.15 no.2
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• pp.56-61
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• 2019

In this study, the failure analysis of the internal tube occurred in the high pressure feedwater heater for power generation boiler of 500 MW supercritical pressure coal fired power plant was investigated. I suggested a prediction model that can diagnose internal tube failure by changing the position of level control valve on the shell side and the suction flow rate of the boiler feedwater pump. The suggested prediction model is demonstrated through additional cases of feedwater system unbalance. The simultaneous comparison of the shell side level control valve position and the suction flow rate of the boiler feedwater pump compared to the normal operating state value, even in the case of the high pressure feedwater heater for the power boiler, It can be a powerful prediction diagnosis.