• Herbal Formula Science
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• v.17 no.2
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• pp.123-132
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• 2009

Acetaminophen (AP) is widely used as an over-the-counter analgesic and antipyretic drug. AP-induced hepatotoxicity is a common consequence of AP overdose and may lead to acute liver failure. In this study, we investigated the liver damage in mice using single dose (300 mg/kg) of AP and the possible protective effects of administration (50-200 mg/kg body weight) of Joo-Juk on acetaminophen-induced liver damage in mice. The alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activities were determined in the plasma of mice. The effect of Joo-Juk on lipid peroxidation product thiobarbituric reacting substances (TBARS) and some antioxidant enzymes superoxide dismutase (SOD), catalase, d-aminolevulinate dehydratase ($\sigma$-ALA-D) activities, and gluthathione peroxidase (GPx), were also evaluated in the mouse liver homogenate. AP caused liver damage as evident by statistically significant increased in plasma activities of AST and ALT. There were statistically significant losses in the activities of SOD, catalase, $\sigma$-ALA-D, and GPx and an increase in TBARS in the liver of AP-treated group compared with the control group. However, Joo-Juk was able to counteract these effects. These results suggest that Joo-juk can act as hepato-protectant against AP toxicity and is a good candidate for further evaluation as an effective chemotherapeutic agent.

• Herbal Formula Science
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• v.16 no.2
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• pp.183-191
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• 2008

Acetaminophen (N-acety1-p-aminophenol, paracetamol) is widely used as an over-the-counter analgesic and antipyretic drug. Intake of a over dose of acetaminophen may result in severe hepatic necrosis. In this study, we investigated the liver damage in mice using single dose (300 mg/kg) of acetaminophen and the possible protective effects of administration (50-200 mg/kg body weight) of SB-Ex on acetaminophen-induced liver damage in mice. The alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activities were determined in the plasma of mice. The effect of SB-Ex on lipid peroxidation product thiobarbituric reacting substances (TBARS) and some antioxidant enzymes superoxide dismutase (SOD), catalase, d-aminolevulinate dehydratase (${\sigma}$-ALA-D) activities, and gluthathione peroxidase (GPx), were also evaluated in the mouse liver homogenate. Acetaminophen caused liver damage as evident by statistically significant increased in plasma activities of AST and ALT. There were general statistically significant losses in the activities of SOD, catalase, ${\sigma}$-ALA-D, and GPx and an increase in TBARS in the liver of acetaminophen-treated group compared with the control group. However, SB-Ex was able to counteract these effects. These results suggest that SB-Ex can act as hepatoprotectives against acetaminophen toxicity and is a good candidate for further evaluation as an effective chemotherapeutic agent.

• The Journal of Engineering Geology
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• v.10 no.2
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• pp.36-51
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• 2000

Almost every year, Korean suffered from the repetitive natural disasters such as typhoons and floods. During last 10 years, Korea experienced annual average of $50 million property damages caused by inundation. To estabilish the flood disaster counter plan, knowledge for flood damage causes based on the field investigations of inundated area is required. The field investigations is focused on technique to document and analyze the meteorological conditions leading to torrential rains, the causes and patterns of flooding, the performance of flood control structures in affected areas, the extent damages and the effectiveness of local emergency response and recovery actions. We did comparative analysis of field investigation techniques. As a major goal of flood hazard map design, one of non structural disaster countermeasures, it was expected to reduce flood damage losses by requiring local governments to implement land-use regulation that would result in safe building practices in flood hazard areas. This requires local governments to develop flood hazard maps to assess how to manage particularly vulnerable floodplain areas. In this study we suggested a design manual and the management system of flood hazard map.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.1
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• pp.101-110
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• 2009

The vascular plants in the Mt. Hoemun were listed 541 taxa composed of 113 families, 354 genera, 473 species, 1 subspecies, 64 varieties and 3 forms. Divided into 541 taxa; woody plants were 151 taxa (27.9%) and herbaceous plants were 390 taxa (72.1%). Based on the list of rare plants by the Korea Forest Service, 10 taxa were recorded in the studied areas; Lilium distichum (Preservation priority order: No. 159), Lilium callosum (No. 191), Tricyrtis dilatata (No. 97), Iris ensata var. sponianea (No. 197), Gastrodia elata (No.9), Aristolochia contorta (No. 151), Paeonia obovata (No. 30: Legal protection species), Prunus yedoensis (No. 110 : Planted species), Viola albida (No. 202), Schpolia japonica (No. 208). Based on the list of Korean endemic plants, 15 taxa were recorded; Cephalotaxus koreana, Lilium amabile, Salix purpurea var. japonica, Pseudostellaria multiflora, Aconitum pseudolaeve var. erectum, Filipendula glaberrima, Weigela subsessilis, etc. Based on the list of approved for delivering overseas of plants, 10 taxa were recorded; Carex okamotoi, Lilium distichum, Clematis trichotoma, Vaccinium oldhami, Paulownia coreana, Asperula lasiantha; etc. Specific plant species by floral region were total 4S taxa (8.3% of all 541 taxa of vascular plants); Gastrodia elata, Paeonia obovata in class V, Carex arenicola, Corydalis grandicalyx in class IV, 5 taxa (Spiraea salicifolia, Schpolia japonica, Asperula lasiantha, etc.) in class III, 7 taxa (Lilium distichum, Iris ensata var. spontanea, Caryopteris incana, etc.) in class II and 28 taxa (Camptosorus sibiricus, Orixa japonica, Lonicera praeflorens, etc.) in class I. The naturalized plants in the surveyed sites were 13 families, 38 genera, 43 species, 2 varieties, 45 taxa (Phleum pratense, Medicago sativa, Sonchus asper, etc.) and naturalization rate was 8.3% of all 541 taxa of vascular plants. Ambrosia artemisiifolia var. elatior an ecosystem disturbing wild plants have been increasing. Therefore, the counter plants for continuous control and conservation are needed on the ecosystem of Mt. Hoemun.

• Progress in Superconductivity
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• v.10 no.1
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• pp.55-59
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• 2008

A Superconductor Flywheel Energy Storage System(SFES) mainly consists of a pair of non-contacting High Temperature Superconductor(HTS) bearings that provide very low frictional losses, a composite flywheel with high energy storage density. The HTS bearings, which offer dynamic stability without active control, are the key technology that distinguishes the SFES from other flywheel energy storage devices, and great effort is being put into developing this technology. The Superconductor Journal Bearing(SJB) mainly consists of HTS bulks and a stator, which holds the HTS bulks and also acts as a cold head. Static properties of HTS bearings provide data to solve problems which may occur easily in a running system. Since stiffness to counter vibration is the main parameter in designing an HTS bearing system, we investigate SJB magnetic force through static properties between the Permanent Magnet(PM) and HTS. We measure stiffness in static condition and the results are used to determine the optimal number of HTS bulks for a 100kWh SFES.

• Toxicological Research
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• v.13 no.4
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• pp.359-365
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• 1997

Many factors are known to be responsible for cerebral ischemic injury, such as excitatory neurotransmitters, increased intraneuronal calcium, or disturbance of cellular energy metabolism. Recently, oxygen free radicals, formed during ischemia/reperfusion, have been proposed as one of the main causes of ischemia/reperfusion injury. Therefore, to investigate the role of oxygen free radical during ischemia/reperfusion, in the present study the effect of endogenous oxygen free radical scavenger, superoxide dismutase / catalase(SOD / catalase) on the release of [$^3$H]-5-hydroxytryptamine([$^3$H]-5-HT) during hypoxia/reoxygenation in rat hippocampal slices was measured. The hippocampus was obtained from the rat brain and sliced 400 gm thickness with manual chopper. After 30 min's preincubation in the normal buffer, the slices were incubated for 20 min in a buffer containing [$^3$H]-5-HT(0.1 $\mu$M, 74 $\mu$Ci) for uptake, and washed. To measure the release of [$^3$H]-5-HT into the buffer, the incubation medium was drained off and refilled every ten minutes through a sequence of 14 tubes. Induction of hypoxia for 20 min (gassing it with 95% N$_2$/5% CO$_2$) was done in the 6th and 7th tube, and oxygen free radical scavenger, SOD / catalase was added 10 minutes prior to induction of hypoxia. The radioactivity in each buffer and the tissue were counted using liquid scintillation counter and the results were expressed as a percentage of the total activity. When slices were exposed to hypoxia for 20 min, [$^3$H]-5-HT release was markedly decreased and a rebound release of [$^3$H]-5-HT was observed on the post-hypoxic reoxygenation period. SOD / catalase did not changed the release of [$^3$H]-5-HT in control group, but inhibited the decrease of [$^3$H]-5-HT release in hypoxic period and rebound increase of [$^3$H]-5-HT in reoxygenation period. This result suggest that superoxide anion may play a role in the hypoxic-, and reoxygenation-induced change of [$^3$H]-5-HT release in rat hippocampal slices.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.9
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• pp.1304-1314
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• 1993

During the last several years, the demand of mobile communication is increasing rapidly due to the convenience of usage. Therefore, the evoluation scenario toward the new cellular network is needed. In this paper, the future prospect of cellular network is considered, and movable-boundary TDMA/BTMA protocol is proposed as a new voice/data integrated multiple access protocol for the future cellular packet radio networks. Then, the performance of movable-bounary TDMA/BTMA protocol is analyzed and compared with that of PRMA protocol by computer simulation. In the proposed movable-boundary TDMA/BTMA protocol, the voice traffic sensitive to delay time is served by TDMA protocol and the data traffic sensitive to loss is served by BTMA protocol. Also, the boundary of voice and data can be moved adaptively by usign SYN character, control byte, voice call counter, ect. Therefore. it could be seen that the performance of movable-boundary TDMA/BTMA protocol is better than that of PRMA protocol with respect to delay and throughput.

• Journal of Society of Preventive Korean Medicine
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• v.1 no.1
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• pp.1-13
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• 1997

Cho, Tak(曺倬)'s Yi-Yang-Pyun(二養編), first published in the 12 year of Kwang-Hae-Kun(光海君) era(1620), is composed of two parts. The first part is an edition of various Confucian scriptures that is used to control and restrain the mind. The second pan, considering mostly of contents borrowed from medical works, anthologies and books on yang-saeng(養生), is used to maintain the well-being of the body. Yi-Yang-Pyun shows several distinct characteristics of Yang-saeng ideas. first, it follows the teachings of Yi, Hwang(李滉) which denotes the state of body and mind according to the Kyung(敬) philosophy. 'Kyung' is a state of being that does not require bondage as it automatically reveres the mind. Therefore, actively fostering the body and mind is to maintain this respective state of being. Second, it has summarized and arranged certain medical contents from the Dong-Eui-Bo-Kam(東醫寶鑑) for the purpose of discovering the truth underlying one's body in an effort to pursue the logics of universal nature. Third, although it was based on the contents of Confucianism related books, it widely encompassed the regimen of Taoism. Fundamentally, the Confucian had regarded the Taoism as a heretic, but accepted it in e influence of Zhu xi(朱熹) who interpretated Can-Tong-Qi(參同契) with Confucian perspectives and put in practice the regimen of Taoism. In this context, Yi-Yang-Pyun also used jointly Taoism-related books with Confucian scriptures. Although Taoist regimen was accepted, elixir(外丹), conjury of Taoist hermit(神仙方術) and issues which run counter to morality like sexual practices(房中術) were not. Most of regimens used were related to disease-prevention and health-enhancement like breathing(服氣法), gym-nastics(導引), Diet(服餌) etc. Ideas of Yi-Yang-Pyun, written from Confucian perspectives, latter heavily influenced on scholars of inner elixir(內丹).

• The Korean Journal of Pain
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• v.2 no.2
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• pp.145-154
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• 1989

Pain is a common and important clinical symptom, and treatments aimed at relieving pain have a central position in medical practice. Recently Transcutaneous Electrical Nerve Stimulation (TENS) has been effectively used to control acute and chronic conditions that produce pain. But the mechanism of analgesia resulting from TENS remains obscure. In order to investigate the analgesic effect of TENS and it's action mechanism, TENS was applied in 40 rabbits with different frequencies, low frequency (2Hz) and high frequency (100Hz), for 20 minutes. And the pain threshold was measured by the temperature before and after stimulation, and an attempt was made to antagonize the stimulation effect with naloxone pretreatment (0.4 mg/kg) The results are as follows: 1) Both low frequency and high frequency TENS resulted in increasing the pain threshold significantly (Both p<0.01). 2) Naloxone pretreatment could antagonize the effect of increasing the pain threshold with low frequency TENS significantly (p<0.01), but not with high frequency TENS. Plasma beta-endorphin was measured by radioimmunoassay using an Beta-Endorphin Kit (Immunonuclear Corporation, Stillwater, Minnesota, USA) and Automatic Gamma Scintillation Counter (Micromedic System 4/2000) before and after stimulation. An attempt was made to reverse the stimulation effect with naloxone pretreatment (0.4 mg/kg). The results are as follows: 1) Low frequency TENS resulted in increasing the level of plasma beta.endorphin significantly (p<0.01), but high frequency TENS did not. 2) Naloxone pretreatment could reverse the effect of increasing the plasma beta-endorphin level with low frequency TENS significantly (p<0.01).

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.8
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• pp.91-98
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• 1999

This paper describes the air flow characteristics inside the throttle valve. Tow-dimensional steady incompressible Navier-Strokes equation are solved numerically with embedding the conceopt of the artificial compressibility and adopting the Baldwin-Lomax turbulence model. With varying the valve opening angles(the Reynolds number )such as 15$^{\circ}$(5000) , 45$^{\circ}$(3000) , 75$^{\circ}$(7000) and 90$^{\circ}$(10000), respectively. tow cases, with a valve shaft and without one, are analysed. The pressure loss between the entrance and exit is severe at 15$^{\circ}$, 100 times as larger as that of 90$^{\circ}$ case, which also depends much on the existece of the valve shaft. The counter rotating vortices are formed over the valve plate with the shaft at only 75$^{\circ}$. They are smally and very large scale in front and back of the valve shaft , respectively. The velocity profiles of 15$^{\circ}$ and 90$^{\circ}$ at the exit are almost symmetric to the horizontal center line, however, the symmetricity is no longer maintained at 45$^{\circ}$ and 75$^{\circ}$ , and in addition, the flow at 75$^{\circ}$ is enforced a lot below center line. The pressure distribution on the walls is largely changed near the valve shaft, and its magnitude becomes great as the valve angle decreases.