• Korean Journal of Environmental Biology
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• v.18 no.3
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• pp.315-322
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• 2000

Effects of the simulated acid rain on the growth response and the structural features were studied with the 3 month old seedlings of G. biloba and P. thunbergii treated with acid rain of pH 5.6, 4.0, 3.2, and 2.4. The diameter and area of tracheid cells in the transectioned stem of G. biloba decreased with acidity of simulated acid rain. The wall thickness of tracheid cells was the thinest at pH 2.4, but there was no different at other levels of pH. Increasing of the acidity, the height of tracheid cells were reduced steadily. The diameter and area of tracheid cells of the transectioned root reduced with decreasing pH of acid rain, but those at pH 3.2 were larger than those at control. The wall thickness and height of tracheid cells of root were gradually decreased with acidity of acid rain. The size variation of the fusiform cambial initials in the stem of G. biloba sections tangentially showed a shortening tendency with treatment of acid rain. The length of ray initials was the shortest at pH 2.4 and reduced with decreasing pH of acid rain. The diameter, area, wall thickness, and height of the tracheid cells in P. thunbergii stem and root decreased with decreasing pH of acid rain. The areas of the pith, cortex, and xylem in P. thunbergii treated with acid rain decreased, but the cortex and pith areas increased significantly after exposure to acid rain of pH 3.2 compared with control.

• 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.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.153-162
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• 2000

A field study was performed to test effectiveness of a bloluminescent genetically engineered microorganism (GEM) for bioremediation process monitoring and control. The study employed Pseudomonas fluorescens HK44 that was the first strain approved for field application in the U.S. for bioremediation purposes. HK44 contains lux gene fused within a naphthalene degradative pathway, allowing this GEM to bioluminesce as it degrades naphthalene as well as substituted naphthalenes and other polycyclic aromatic hydrocarbons (PAHs) , Results showed that HK44 was maintained in both PAH-contarninated and uncontaminated soils even 660 days after inoculation. HK44 was able to produce bioluminescence in response to PAHs in soil. Although effectiveness of chemical remediation was not assessed due to heterogeneous distribution of contaminants, decreased concentration of naphthalene was shown in the soils, Taken together, HK44 was useful for in situ bioremediation process monitoring and control. This work is so far the only field release of a GEM for bioremediation purposes.

• The Journal of Korean Society of Virology
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• v.30 no.3
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• pp.179-187
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• 2000

The etiology of rheumatic arthritis (RA) is associated with a number of genetic and environmental factors, but is not definitively elucidated. Recently, more attention has been paid to the possibility of microbial etiology in the pathogenesis of RA, because many different infectious agents have been reported to precede the onset or exacerbation of RA. Adenovirus (ADV) may be one cause of persistent or recurrent inflammatory arthritis. Varicella zoster virus (VZV) arthritis is detected frequently in RA patients treated with low dose methotrexate. The demonstration of simultaneous presence of both viral agents of specific viral nucleic acid in synovial fluids from synovitis patients would provide more direct evidence for arthritis etiological relationship, but there are no confirmed results. Therefore, we studied the ability of adenovirus and VZV to establish coinfection and persistent infection in synovial fluid from synovitis patients. The presence of viral agents in the synovial fluid demonstrated by isolation of cell culture, enzyme immunoassay and nested-PCR. The synovial fluids were also investgated for the presence of viral nucleic acid by nested-PCR using specific primer. ADV produced 220 bp and VZV produced 447 bp by each nested-PCR with specific primers. We detected 4/6 cases (66.7%) with persistent infection of ADV and 5/6 cases (83.3%) of VZV with 13 synovial fluids (between 7 to 52 day intervals) from synovitis patients by monoclonal ErA and nested-PCR. 21/28 cases (75%) with coinfection of adenovirus and VZV with synovial fluids from synovitis patients by nested-PCR. ADV and VZV coinfection and persistent infection of synovial fluids may provide a chronic antigenic stimuli to the immune system therefore provoking a continuing inflammatory response and caused the possibility of synovitis and arthritis.

• The Journal of Korean Society of Virology
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• v.30 no.1
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• pp.11-18
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• 2000

Since $Hantavax^{TM}$, formalin inactivated Hantaan virus vaccine (10,240 ELISA units/ml), has been developed in 1990 to prevent against haemorrhagic fever with renal syndrome (HFRS) caused by Hantaan or Seoul virus, it has been commercially available in Korea. Twenty-one healthy people were booster shot once and twice after primary basic vaccination with $Hantavax^{TM}$. Seroconversion rates were measured by immunofluorescent antibody technique (IFAT), enzyme-linked immunosorbent assay (ELISA), high density composite particle agglutination (HDPA), and plaque reduction neutralization test (PRNT). Seroconversion rates of 21 vaccinees at one year after primary basic vaccination were 52.3%, 95.2%, 0.0%, 47.6%, and 28.6%, and 13 vaccinees at one month after 1st booster vaccination were 100%, 100%, 30.7%, 100% and 100% by IFAT, ELISA (IgG, IgM), HDPA and PRNT, respectively. Seroconversion rates declined slightly by twenty months, and they were 84.6%, 92.3%, 0.0%, 84.6% and 69.2% by IFAT, ELISA (IgG, IgM), HDPA and PRNT, respectively. Seroconversion rates of 9 vaccinees at three months after 2nd booster vaccination were 100%, 100%, 0.0%, 100%, and 88.9%, and 16 vaccinees at one year after the 2nd booster vaccination were 87.5%, 93.8%, 0.0%, 87.5% and 81.3% by IFAT, ELISA (IgG, IgM), HDPA and PRNT, respectively. Based on the above result $Hantavax^{TM}$ has proved a vigorous anamnestic response after the 1st and the 2nd booster vaccination and has persisted higher fluorescence, agglutination and neutralizing antibody titers in vaccinees.

• Journal of Chest Surgery
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• v.33 no.4
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• pp.277-284
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• 2000

Background: Coronary artery bypases grafting in the old aged is associated with high mortality and morbidity, and it is difficult to perform if the coronary artery is diffusely disease. Recently it has been known that platelet derived growth factor(PDGF), especially PDGF-BB, stimulates angiogenesis. Material and Method: New Zealand white rabbit were used. In an attempt to achieve effevtive cardiac revasculatrization without vascular anastmosis, we divided into three groups(group I : Left anterior descending artery(LAD) was occluded by ligature, group II : Bilateral internal mammary vascular pedicles were dissected and implanted into myocardium, group III : The vascular pedicles were implanted into myocardium and PDGF-BB was injected into the myocardial tissue). Two weeks after IMA implantation, the proximal region of implanted LAD was ligated. Four days after LAD ligation angiogram, triphenyl tetrazolium chloride(TTD) staining and hematoxylin eosin staining were performed. Result: 1. Survival rate in group II was significantly higher than that in group I (P<0.05), and survival rate in group III was signficantly higher than that in group II(53% vs 93%, P<0.01). 2. There were significant differences in the ratio of area of necrosis to area at risk between group I and group II, and between group II and group III (P<0.01). 3. Microangiogram for angiogenic response revealed wide area of extensive revascularization with patent vessels in group III. 4. Histologic findings of three groups showed that polymorphonuclear leukocyte infiltration was minimal in group II and none in group III. Conclusion: PDGF-BB can establish functinal cardiac revasculatization through systemic vessels implanted directly into the myocardium.

• Korean Security Journal
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• no.3
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• pp.83-116
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• 2000

Many concerns have been raised for importance of disaster management after 1990's numerous urban disasters in Korea. When the primary function of government is to protect lives and property of citizens, disaster management should be included in the mainstream of public administration and many hazard countermeasures should be carried out for that purpose. The principal purpose of this research is to establish ways and means needed to improve the disaster management system in Korea. This paper is split into five chapters. Chapter I is the introduction part. Chapter II introduces the reader to a disaster management theory, and deals with various disaster management systems of foreign countries such as the U.S.A. and Japan, Chapter III describes and characterizes the Korea's current disaster management system. The Korean disaster management system has been reestablished through the enactment of the Disaster Management Act of 1995 and the full revision of Natural Hazards Management Act of 1995 after series of catastrophic man-made disasters since 1993. Chapter IV is devoted to the establishment of an effective disaster management system in Korea. In this chapter, I discusses measures needed to improve the quality of CDMB(Central Disaster Management Bureau)'s service to the people. I strongly reemphasize the effectiveness of a comprehensive risk-based, all-hazard national emergency management system that addresses preparedness, mitigation, response, and recovery. To that end the Administration should develop legislation, new policies, and organizational plans to invigorate the agency with a refocussed mission. Chapter V is a conclusion. As the demand for citizens'welfare has been continuously increased in the localization, the importance of disaster management is emerging subject in the public sector. The disaster management carries out complicated affairs and manages diverse objects, the cooperation/connection system of the central-local government and citizens, and non-governmental organization should be established.

• Journal of the Korean Society of Tobacco Science
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• v.22 no.1
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• pp.51-57
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• 2000

The feeding preference of cigarette beetles, Lasioderma serricorne F., was tested using various leaf litters. The number of the trapped L. serricome was 45.25$\pm$10.44 at flue-cured leaf tobacco, Nicotiana tabacum L., 23.50$\pm$6.0 at chinese juniper, Juniperus chinensis L., 1l.75$\pm$4.99 at oak, Qqercus acutissiuma C., and 1l.50$\pm$2.52 at rice-straw, (Oryza. sativa L.). The response of oviposition was 93.20$\pm$26.22 at flue-cured leaf tobacco, 53.60$\pm$11.82 at chinese juniper, 48.20$\pm$20.90 at oriental arborvitae, Thuja orientalis L., 31.80$\pm$18.10 at cherry-tree, Prunus serrulata var. spontanea M., and 29.40$\pm$13.7 at rice-straw. However, the oviposition was respectively low at gingko, Ginkgo biloba L.,(5.40$\pm$2.97), turf grass, Zoysia japonica S., (5.20$\pm$13.7), and oak (3.00$\pm$l.41). The augmentation was maximum at chinese juniper (27.33$\pm$19.44 of emerged adults) followed by Magnolia obovata (8.50$\pm$9.33). Fifty percent of the tested species leaf litters including cherry-tree did not show any augmentation. The adult activities after hibernation were primarily found in May and June at Kwangju and Suwon, and in April at Chungju. The field activity of L. serricome at Suwon was mostly lower than that at other places, except in August at Chungju. The first appearance of L. serricome was observed earlier at Chungju and Kwangju than at Suwon, and the frequency of insect appearance was high in July, August, and September. L. serricome could hibernate by feeding on many kinds of plant leaf litters and it's population could be maintained in the open field in Korea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.77-85
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• 2000

Simulation of local external forcing and its response in the rotation table experiment has been investigated. Spatially-uniform external forcings have been applied in many experimental studies, however, based on the fact that the north-south distribution of the wind-stress curl and the existence of local maximum of the sea surface heat loss in the northern part of the East Sea, new method of combined effects of local forcings has been employed in separate experiments. Carefully designed local source or sink at the bottom of the cylindrical container can produce horizontal pressure gradient within the Ekman layer, and consequently the interior also attains the same pressure gradient that produces geostrophic interior circulation. In order to keep free surface during the local-surface cooling, a side-wall cooling method is suggested. For the various type of local forcing including the effects local cooling and the periodic change of local wind-stress curl, western-boundary flow in terms of its strength, position of separation from the boundary have been observed.

• Journal of Korea Water Resources Association
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• v.33 no.4
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• pp.427-435
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• 2000

It is often crucial to obtain a map of flood inundated area with more accurate and rapid manner. This study attempts to evaluate the potential of satellite synthetic aperture radar (SAR) data for mapping of flood inundated area in Imjin river basin. Multitemporal RADARSAT SAR data of three different dates were obtained at the time of flooding on August 4 and before and after the flooding. Once the data sets were geometrically corrected and preprocessed, the temporal characteristics of relative radar backscattering were analyzed. By comparing the radar backscattering of several surface features, it was clear that the flooded rice paddy showed the distinctive temporal pattern of radar response. Flooded rice paddy showed significantly lower radar signal while the normally growing rice paddy show high radar returns, which also could be easily interpreted from the color composite imagery. In addition to delineating the flooded rice fields, the multitemporal radar imagery also allow us to distinguish the afterward condition of once-flooded rice field.