• The Korean Journal of Nuclear Medicine
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• v.39 no.6
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• pp.421-429
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• 2005

Purpose: It has been postulated that dopamine release in the striatum underlies the reinforcing properties of nicotine. Substantial evidence in the animal studies demonstrates that nicotine interacts with dopaminergic neuron and regulates the activation of the dopaminergic system. The aim of this study was to visualize the dopamine release by smoking in human brain using PET scan with $[^{11}C]raclopride$. Materials and Methods: Five male non-smokers or ex-smokers with an abstinence period longer than 1 year (mean age of $24.4{\pm}1.7$ years) were enrolled in this study $[^{11}C]raclopride$, a dopamine D2 receptor radioligand, was administrated with bolus-plus-constant infusion. Dynamic PET was performed during 120 minutes ($3{\times}20s,\;2{\times}60s,\;2{\times}120s,\;1{\times}180s\;and\;22{\times}300s$). following the 50 minute-scanning, subjects smoked a cigarette containing 1 mg of nicotine while in the scanner. Blood samples for the measurement of plasma nicotine level were collected at 0, 5, 10, 15, 20, 25, 30, 45, 60, and 90 minute after smoking. Regions for striatal structures were drawn on the coronal summed PET images guided with co-registered MRI. Binding potential, calculated as (striatal-cerebellar)/cerebellar activity, was measured under equilibrium condition at baseline and smoking session. Results: The mean decrease in binding potential of $[^{11}C]raclopride$ between the baseline and smoking in caudate head, anterior putamen and ventral striatum was 4.7%, 4.0% and 7.8%, respectively. This indicated the striatal dopamine release by smoking. Of these, the reduction in binding potential in the ventral striatum was significantly correlated with the cumulated plasma level of the nicotine (Spearman's rho=0.9, p=0.04). Conclusion: These data demonstrate that in vivo imaging with $[^{11}C]raclopride$ PET could measure nicotine-induced dopamine release in the human brain, which has a significant positive correlation with the amount or nicotine administered bt smoking.

• Pediatric Infection and Vaccine
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• v.12 no.2
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• pp.166-177
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• 2005

Purpose : The purpose of this study was to examine the molecular epidemiology and genetic variability of adenovirus(Ad) serotypes Ad1, Ad2, and Ad5 over 14 years in Korea. Methods : A total of 382 adenoviral strains isolated from the nasopharyngeal aspirates of children with lower respiratory tract infections in Seoul, Korea from November 1990 to February 2003 were serotyped by neutralization assay with type-specific antisera. Viral DNAs were extracted from infected cell lysates by the modified Hirt procedure. Genome type(GT) was determined by DNA restriction analysis with 12 restriction enzymess(BamHI, BclI, BglI, BglII, BstEII, EcoRI, HindIII, HpaI, SalI, SmaI, XbaI, and XhoI). To evaluate the genetic relatedness, pairwise comigrating restriction fragments(PCRF) analysis was performed. Results : Of 382 strains, 33 strains(9%) were Ad1, 45 strains(12%) were Ad2, and 24 strains(6%) were Ad5. Eighteen GTs(Ad1p1-Ad1p7, Ad1a, Ad1b, Ad1b1-Ad1b3, Ad1c, Ad1d, Ad1e, Ad1e1, Ad1e2, Ad1f) among Ad1, 24(Ad2p1-Ad2p11, Ad2a, Ad2a1-Ad2a6, Ad2b, Ad2c, Ad2d, Ad2e, Ad2e1-Ad2e3) among Ad2, and 10(Ad5p1, Ad5p2, Ad5a, Ad5a1-Ad5a7) among Ad5 strains were identified. One or two strains of the vast majority of GTs were isolated during the study period while a few GTs were identified sporadically with more than 2 strains. It is notable that some GTs such as Ad1p5 and Ad5a1 appeared in cluster during a short period. In analysis of genetic relatedness, the degree of PCRFs(pairwise comigrating restriction fragments) for Ad1 varied from 79 to 99%, for Ad2, 82 to 99%, and for Ad5, 85 to 99%. Conclusion : This study established the comprehensive nomenclature systems of Ad1, Ad2, and Ad5. Diverse GTs identified in this study have crucial implications in the genomic diversity and epidemiological characteristics of Ad1, Ad2, and Ad5.

• Economic and Environmental Geology
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• v.45 no.6
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• pp.643-659
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• 2012

The Chungju Fe-REE deposit is located in the Kyemyeongsan Formation of the Ogcheon Group. The Kyemyeongsan Formation includes meta-volcanic rocks and pegmatite hosted REE deposit which show different kind of REE-containing minerals. The meta-volcanic rocks hosted REE deposits' main REE minerals are allanite, zircon, apatite, and sphene, whereas the pegmatite hosted REE deposits is mainly composed of fergusonite, and karnasurtite, zircon, thorite. The meta-volcanic rock hosted major REE mineral is allanite as the form of aggregation and contains 23.89-29.19 wt% TREO (Total Rare Earth Oxide), 4.71-9.92 wt% $La_2O_3$, 11.30-14.33 wt% $Ce_2O_3$, 0.11-0.29 wt% $Y_2O_3$, 0.15-0.94 wt% $ThO_2$, as a formula of (Ca, Y, REE, Th)$_{2.095}$(Mg, Al, Ti, Mn, $Fe^{3+})_{2.770}(SiO_4)_{2.975}(OH)$. Accompanying REE in a coupled substitution for $Ca^{2+}$ (M1 site) and $Al^{3+}-Fe^{2+}$ (M2 site) leads to a large chemical variety. Due to the allanite's high contents of Fe, it belongs to Ferrialanite. The pegmatite hosted deposit's domi-nant REE mineral is fergusonite as prismatic or subhedral grains associated with zircon, fluorite and karnasurtite. Geochemical composition of the fergusonite($YNbO_4$) suggests substitution of Y-REE and Y-Th in A-site, and Nb-Ta-Ti in B-site, furthermore the proportion of $Y_2O_3$ and $Nb_2O_5$ is oddly 1:1.5 comparing to the ideal ratio 1:1 and Nb is higher than Y, also A-site Y actively substitutes with REE. Karnasurtite in pegmatite variously ranges 9.16-22.88 wt% $Ce_2O_3$, 2.15-9.16 wt% and $La_2O_3$, 0.44-10.8 wt% $ThO_2$, as a calculated formula (Y, REE, Th, K, Na, Ca)$_{1.478}(Ti, Nb)_{1.304}$(Mg, Al, Mn, $Fe^{3+})_{0.988}$(Si, P)$_{1.431}O_7(OH)_4{\cdot}3H_2O$. Firstly the 870-860 Ma is the initial age of the supercontinent Rhodinia dispersal and subsequent A-1 type volcanism, which contains Fe, REE, and HFS(High Field Strength elements; Nb, Zr, Y etc.) elements in Fe-rich meta-volcanic rocks dominant Kyemyeongsan Formation, might mineralized allanite. Another synthesis is that regional metamorphism at late Paleozoic 300-280 Ma(Cho et al., 2002) might cause allanite mineralization. Also pegmatite REE mineralization highly related to the granite intrusion over the Chungju area in Jurassic(190 Ma; Koh et al., 2012). Otherwise above all, A-1 type volcanism at the same time of the Kyemyeongsan Formation development, regional metamorphism and pegmatite, might have caused REE mineralization. Although REE ore bodies display a close spatial association, each ore bodies display temporal distinction, different mineral assemblage and environment of ore formation.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.1
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• pp.83-96
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• 2016

Through the research and analysis on the vegetation environment, flora of habitats through documentary and field studies over 14 habitats of Euryale ferox Salisbury within Jeollabukdo, with the objective of acquiring the basic data for forming an environment based on plantation of reservoirs that are composed with Euryale ferox, the following results were obtained. 1. The entire flora of the 14 habitats appeared to be 79 families, 211 genus, 298 species, two subspecies, 30 varieties and six forma, thus, a total of 336 taxa was confirmed. Among these, emergent water plants appeared to compose 17 taxa, floating-leaved plants to compose seven taxa including Euryale ferox floating plants to compose five taxa and submerged water plants to compose two taxa. As a result of analyzing the similarity only over the water plants. The lowest similarity rate appeared between Gamdong Reservoir and Aedang Reservoir, as the similarity rate between the two regions appeared to be 0% as a result of the analysis. Floating-leaved plants, lotuses and caltrops, appeared to be equally inhabiting in Hanseongji at Jeongeup and Seoknam Reservoir at Gochang, which showed the highest similarity rate, in addition to Euryale ferox. 2. When examining the appearance frequency of aquatic plants per growth type, Actinostemma lobatum and Phragmites communis, in addition to Euryale ferox each appeared 11 times, showing a high frequency of 78.6% and Trapa japonica, which is a floating-leaved water plant, appeared ten times(71.4%) and Zizania latifolia appeared eight times(57.1%). In addition, the appearance rate appeared to be high in the order of Persicaria thunbergii, Leersia sayanuka, Ceratophyllum demersum, Echinochloa crusgalli var. oryzicola, Scirpus maritimus, and Nelumbo nucifera. 3. The rare plants discovered in the Euryale ferox habitats pursuant to the IUCN evaluation standards was confirmed to be composed of five taxa, with three taxa including the least concerned species(LC), Melothria japonica at Yanggok Reservoir, Hydrocharis dubia at Myeongdeokji and Ottelia alismoides at Daewi Reservoir, in addition to vulnerable species(VU), Utricularia vulgaris at Sangpyeong Reservoir, along with Euryale ferox. 4. Most of the group or community types of the natural habitats of Euryale ferox appeared to be the Euryale ferix community' and the Daewi Reservoir of Gunsan was defined as caltrop + Euryale ferox + Nymphoides indica community. The green coverage ratio of Euryale ferox per natural habitats showed a considerably huge deviation from 0.03 to 36.50 and as the average green coverage ratio was appropriated as 9.8, it can be considered that maintaining the green coverage ratio of Euryale ferox in a 10% level would be advisable when forming a reservoir with Euryale ferox as the key composition species. 5. The vegetation community nearby the natural habitats of Euryale ferox per research subject area appeared to be composed of three Leersia japonica communities, two communities each for Zizania latifolia community and Trapa japonica community and one community each for Nelumbo nucifera community, Nymphoides peltata + Typha orientalis community, Trapa japonica + Nelumbo nucifera community, Hydrocharis dubia community, Leersia japnica + Paspalum distichum var. indutum community and Euryale ferox + Trapa japonica community, showing a slight difference depending on the location conditions of each reservoir. Thus, this result may be suggested as a guideline to apply when allocating the vegetation ratio and the types of floating-leaved plants upon planting plants in reservoirs with Euryale ferox as the main companion species.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.1
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• pp.93-106
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• 2014

In this study, Analyze environment of location, investigation into vegetation resources, survey management status and establish to classify the management area for Natural monument No.374 Pyengdae-ri Torreya nucifera forest. The results were as follows: First, Torreya nucifera forest is concerned about influence of development caused by utilization of land changes to agricultural region. Thus, establish to preservation management plan for preservation of prototypical and should be excluded development activity to cause the change of terrain that Gotjawal in the Torreya nucifera forest is factor of base for generating species diversity. Secondly, Torreya nucifera forest summarized as 402 taxa composed 91 familly 263 genus, 353 species, 41 varieties and 8 forms. The distribution of plants for the first grade & second grade appear of endangered plant to Ministry of Environment specify. But, critically endangered in forest by changes in habitat, diseases and illegal overcatching. Therefore, when establishing forest management plan should be considered for put priority on protection. Thirdly, Torreya nucifera representing the upper layer of the vegetation structure. But, old tree oriented management and conservation strategy result in poor age structure. Furthermore, desiccation of forest on artificial management and decline in Torreya nucifera habitat on ecological succession can indicate a problem in forest. Therefore, establish plan such as regulation of population density and sapling tree proliferation for sustainable characteristics of the Torreya nucifera forest. Fourth, Appear to damaged of trails caused by use. Especially, Scoria way occurs a lot of damaged and higher than the share ratio of each section. Therefore, share ratio reduction Plan should be considered through the additional development of tourism routes rather than the replacement of Scoria. Fifth, Representing high preference of the Torreya nucifera forest tourist factor confirmed the plant elements. It is sensitive to usage pressure. And requires continuous monitoring by characteristic of Non-permanent. In addition, need an additional plan such as additional development of tourism elements and active utilizing an element of high preference. Sixth, Strength of protected should be differently accordance with importance. First grade area have to maintenance of plant population and natural habitats. Set the direction of the management. Second grade areas focus on annual regeneration of the forest. Third grade area should be utilized demonstration forest or set to the area for proliferate sapling. Fourth grade areas require the introduced of partial rest system that disturbance are often found in proper vegetation. Fifth grade area appropriate to the service area for promoting tourism by utilizing natural resources in Torreya nucifera forest. Furthermore, installation of a buffer zone in relatively low ratings area and periodic monitoring to the improvement of edge effect that adjacent areas of different class.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.27-41
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• 2014

This study aims to investigate the history, cultural values prototype through literature analysis, characteristics of construction, location, space structure and landscape characteristics by Arc-GIS on the Munam pavilion(聞巖亭) in Changnyeong. The results were as follows. First, Shin-cho((辛礎, 1549~1618) is the builder of the Munam pavilion and builder's view of nature is to go back to nature. The period of formation of Munam pavilion is between 1608-1618 as referred from document of retire from politics and build a pavilion. Secondly, Munam pavilion is surrounded by mountains and located at the top of steep slope. Pavilion was known as scenic site of the area. But damaged in a past landscape is caused by near the bridge, agricultural facilities, town, the Kye-sung stream of masonry and beams. Thirdly, Munam pavilion is divided into the main space, which is located on the pavilion, space in located on the pavilion east and west and the orient space, which is located on the Youngjeonggak. Of these, original form of Munam pavilion is a simple structure composed of pavilion and Munam rock, thus at the time of the composition seems to be a direct entry is possible, unlike the current entrance. Fourth, Spatial composition of Munam pavilion is divided into vegetation such as Lagerstroemia indica trees in Sa-ri in Changnyeong, ornament such as letters carved on the rocks and pavilion containing structure. The vegetation around the building is classified as precincts and outside of the premises. Planting of precincts was limited. Outside of area consists of front on the pavilion, which is covered with Lagerstroemia Indica forest and Pinus densiflora forest at the back of the pavilion. Ofthese,LargeLagerstroemiaIndicaforestcorrespondstothenaturalheritageasHistoricalrecordsofrarespeciesresourcesthatareassociated withbuilder. Letterscarvedontherocksrepresenttheboundaryof space, which is close to the location of the Munam pavilion and those associated with the builder as ornaments. Letters carved on the rocks front on the pavilion are rare cases that are made sequentially with a constant direction and rules as act of record for families to honor the achievements. Fifth, 'The eight famous spots of Munam' is divided into landscape elements that have nothing to do with bearing 4 places and landscape elements that have to do with bearing 4 places. Unrelated bearings of landscape elements are Lagerstroemia indica trees in Sa-ri in Changnyeong, Pinus densiflora forest at the back of the pavilion, Okcheon valley, Gwanryongsa temple and Daeheungsa temple. Bearing that related element of absolute orientation, which is corresponding to the elements are Daeheungsa temple, Hwawangsan mountain, Kye-sung stream and Yeongchwisan mountain. Relative bearing is Gwanryongsa temple, Yeongchwisan mountain and Kye-sung stream Gongjigi hill. At Lagerstroemia indica trees in Sa-ri in Changnyeong, Pinus densiflora forest at the back of the pavilion, Kye-sung stream and Okcheon valley, elements are exsting. Currently, it is difficult to confirm the rest of the landscape elements. Because, it is a generic element that reliable estimate of the target and locations are impossible for element. Munam pavilion is made for turn to nature by Shin-cho(辛礎). That was remained a record such as Munamzip(聞巖集) and Munamchungueirok(聞巖忠義錄) that is relating to construction of pavilion. Munam pavilion located in a unique form, archival culture through the letters carved on the rocks and Large Lagerstroemia indica forest and through eight famous spots, cultural landscape elements can be assumed that those elements are remained.

• The Journal of Korean Society for Radiation Therapy
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• v.27 no.1
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• pp.61-71
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• 2015

Purpose : 3D Printers are used to create three-dimensional models based on blueprints. Based on this characteristic, it is feasible to develop a bolus that can minimize the air gap between skin and bolus in radiotherapy. This study aims to compare and analyze air gap and target dose at the branded 1 cm bolus with the developed customized bolus using 3D printers. Materials and Methods : RANDO phantom with a protruded tumor was used to procure images using CT simulator. CT DICOM file was transferred into the STL file, equivalent to 3D printers. Using this, customized bolus molding box (maintaining the 1 cm width) was created by processing 3D printers, and paraffin was melted to develop the customized bolus. The air gap of customized bolus and the branded 1 cm bolus was checked, and the differences in air gap was used to compare $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$ and $V_{95%}$ in treatment plan through Eclipse. Results : Customized bolus production period took about 3 days. The total volume of air gap was average $3.9cm^3$ at the customized bolus. And it was average $29.6cm^3$ at the branded 1 cm bolus. The customized bolus developed by the 3D printer was more useful in minimizing the air gap than the branded 1 cm bolus. In the 6 MV photon, at the customized bolus, $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$, $V_{95%}$ of GTV were 102.8%, 88.1%, 99.1%, 95.0%, 94.4% and the $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$, $V_{95%}$ of branded 1cm bolus were 101.4%, 92.0%, 98.2%, 95.2%, 95.7%, respectively. In the proton, at the customized bolus, $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$, $V_{95%}$ of GTV were 104.1%, 84.0%, 101.2%, 95.1%, 99.8% and the $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$, $V_{95%}$ of branded 1cm bolus were 104.8%, 87.9%, 101.5%, 94.9%, 99.9%, respectively. Thus, in treatment plan, there was no significant difference between the customized bolus and 1 cm bolus. However, the normal tissue nearby the GTV showed relatively lower radiation dose. Conclusion : The customized bolus developed by 3D printers was effective in minimizing the air gap, especially when it is used against the treatment area with irregular surface. However, the air gap between branded bolus and skin was not enough to cause a change in target dose. On the other hand, in the chest wall could confirm that dose decrease for small the air gap. Customized bolus production period took about 3 days and the development cost was quite expensive. Therefore, the commercialization of customized bolus developed by 3D printers requires low-cost 3D printer materials, adequate for the use of bolus.

• Economic and Environmental Geology
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• v.39 no.4 s.179
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• pp.369-384
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• 2006

Korean Peninsula, located on the southeastern part of Eurasian plate, belongs to the intraplate region. The characteristics of intraplate earthquake show the low and rare seismicity and the sparse and irregular distribution of epicenters comparing to interplate earthquake. To evaluate the exact seismic activity in intraplate region, long-term seismic data including historical earthquake data should be archived. Fortunately the long-term historical earthquake records about 2,000 years are available in Korea Peninsula. By the analysis of this historical and instrumental earthquake data, seismic activity was very high in 16-18 centuries and is more active at the Yellow sea area than East sea area. Comparing to the high seismic activity of the north-eastern China in 16-18 centuries, it is inferred that seismic activity in two regions shows close relationship. Also general trend of epicenter distribution shows the SE-NW direction. In Korea Peninsula, the first seismic station was installed at Incheon in 1905 and 5 additional seismic stations were installed till 1943. There was no seismic station from 1945 to 1962, but a World Wide Standardized Seismograph was installed at Seoul in 1963. In 1990, Korean Meteorological Adminstration(KMA) had established centralized modem seismic network in real-time, consisted of 12 stations. After that time, many institutes tried to expand their own seismic networks in Korea Peninsula. Now KMA operates 35 velocity-type seismic stations and 75 accelerometers and Korea Institute of Geoscience and Mineral Resources operates 32 and 16 stations, respectively. Korea Institute of Nuclear Safety and Korea Electric Power Research Institute operate 4 and 13 stations, consisted of velocity-type and accelerometer. In and around the Korean Peninsula, 27 intraplate earthquake mechanisms since 1936 were analyzed to understand the regional stress orientation and tectonics. These earthquakes are largest ones in this century and may represent the characteristics of earthquake in this region. Focal mechanism of these earthquakes show predominant strike-slip faulting with small amount of thrust components. The average P-axis is almost horizontal ENE-WSW. In north-eastern China, strike-slip faulting is dominant and nearly horizontal average P-axis in ENE-WSW is very similar with the Korean Peninsula. On the other hand, in the eastern part of East Sea, thrust faulting is dominant and average P-axis is horizontal with ESE-WNW. This indicate that not only the subducting Pacific Plate in east but also the indenting Indian Plate controls earthquake mechanism in the far east of the Eurasian Plate. Crustal velocity model is very important to determine the hypocenters of the local earthquakes. But the crust model in and around Korean Peninsula is not clear till now, because the sufficient seismic data could not accumulated. To solve this problem, reflection and refraction seismic survey and seismic wave analysis method were simultaneously applied to two long cross-section traversing the southern Korean Peninsula since 2002. This survey should be continuously conducted.

• Journal of Korean Society of Forest Science
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• v.84 no.3
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• pp.286-298
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• 1995

This study was carried out to investigate the effect of forest soil acidification on the distribution of exchangeable cations($Ca^{2+}$, $Mg^{2+}$, $Al^{3+}$) and heavy metals(Cu, Zn, Mn, Pb, Cd) in soil, and to understand the relation of the soil chemical properties and the distribution of nutrients and hear metals in fine root and foliage. The results through survey on the long - term change of soil pH and the contents of nutrient and heavy metal in soil, fine root and foliage by 2 sites near Ulsan - Onsan industrial estate and 2 sites in limited development district are summarized as follows : 1. The average forest soil pH(A horizon) in Ulsan had been proceeded down to 3.73 in deciduous forest and 3.86 in coniferous forest in 1994 from 4.45 and 4.78 in 1987, respectively, which indicated serious soil acidification. As comparing soil pH among sites, Dongcheon coniferous forest(pH 4.57) in limited development district showed the highest values and Dangwol deciduous forest(pH 3.19) near Onsan industrial estate showed the lowest values in 1994. 2. Contents of exchangeable calcium in forest soils of limited development district where showed much higher soil pH than industrial estate were 3.5 times more in deciduous forest soil and 11 times more in coniferous forest soil than in industrial estate, and contents of exchangeable magnesium were also 4.5 and 5 times more in limited development district than in industrial estate, respectively. However contents of exchangeable aluminium which had been supposed more in forest soil of industrial estate were more in limited development district. 3. Contents of calcium and magnesium in fine root of deciduous trees(A hirsuta. Q. acutissima) were 3.6 and 1.7 times more in limited development district than in industrial estate, respectively, and those of coniferous trees(P. rigida, P. thunbergii) were 4.6 and 1.5 times more in Limited development district than in industrial estate, respectively. Also contents of calcium and magnesium in foliage of deciduous trees were 1.1 and 2.2 times more in limited development district than in industrial estate, respectively, and those of coniferous trees were 1.8 and 3.3 times more in limited development district, respectively. And contents of aluminium in fine root and foliage were nearly as same as in soil. 4. Ca/Al molar ratios in soil and fine root, which could be related with the dgree of soil acidification and Al toxicity on trees, were Less than 1 in all sites except Dongcheon, suggesting that the soil and fine root in the sites have high sensitivity to soil acidification and the decrease in nutrient uptake and root enlargement. The Ca/Al molar ratios in soil and fine root in coniferous forest were highly correlated with the soil pH one another. 5. Contents of Cu, Zn and Pb in soil, fine root and foliage were more in industrial estate than in limited development district in both deciduous and coniferous forests, however, oppositely contents of Mn and Cd in soil were more in limited development district than in industrial estate.

• Radiation Oncology Journal
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• v.14 no.1
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• pp.17-23
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• 1996

Purpose : To evaluate the role of combination therapy of external radio-therapy and chemotherapy in the management of advanced esophageal cancer as a primary treatment compared with radiation therapy alone. Materials and Methods : A retrospective review of evaluable 55 esophageal cancer patients referred to the Department of Therapeutic Radiology, Paik Hospital for the external radiotherapy between Jul, 1983 and Dec. 1994 was undertaken. Combined therapy patients (A group) were 30 and radiation alone patients (B group) were 25. Median age was 60 years old in A group (ranges : 42-81) and 65 years old in B group (ranges : 50-81). The male patients were 53. The fifty patients had squamous cell carcinomas. Radiation doses of 2520-6480c0y were delivered over a period of 4-7weeks, using 4MV LINAC. Chemotherapy was administered in bolus injection before, after, or during the course of external radiotherapy. The local control rate and patterns of failure according to both treatment modalities and 1, 2 year survival rates according to prognostic factors (stage, tumor length, radiation dose etc.) were analysed. Resuts : Median follow up Period was 7 months (range : 2-73 months). Median survival was 7.5 months (20 days-29 months) in A group and 5 months (20 days-73 months) in B group. The 1, 2 YSRs were $26.7\%$, $8.9\%$ in A group, $12.7\%$, $4.3\%$ in B group (p>0.05), respectively. The 1, 2 YSRs according to stage(II/III), tumor length (5cm more or less). radiation dose (5000cGymore or less) of A and B group were analyzed and the differences of survival rates of both treatments were not statistically significant. But among group B, patients who received 5000cGy or more showed significant survival benefits (p<0.05). The treatment response rates of A and B group were $43.8\%$. $25.0\%$, respectively. Complete response rate of $25.0\%$ in A and $8.3\%$ in B were achieved. The local failure and distant metastsis were $52.4\%$. $23.8\%$ in A group, $64.3\%$, $14.3\%$ in 8 group, respectively. The combination therapy revealed more frequent leukopenia and nausea/vomiting than radiation alone group, but degree of side effects was only mild to moderate. Conclusion : The combined external radiotherapy and chemotherapy for advanced esophageal cancer appears to improve the response rate, local control rate and survival rate, but the improvement was not statistically significant. The side effects of combined modalities were mild to moderate without significant morbidity. Therefore it may be worthwhile to continue the present combined external radiotherapy and chemotherapy in the management of advanced esophageal cancer to confirm our result.