• Economic and Environmental Geology
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• v.20 no.1
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• pp.19-34
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• 1987

The Nokdong As-Zn deposit, located 28 km south of Kyeongju City, Southern Korea, has been investigated by a deep drilling programme. The mineralized zone is roughly 290m long and 180m wide at surface and is hosted in a pipe diatreme infilled with poor to well bedded felsic volcaniclastics. The diatreme was formed by explosive volcanic activity, of probably early Tertiary age, subsequent hydrothermal alteration and mineralization took place concurrently within stratigraphic layers in diatreme. Coarse volcaniclastics in the center part of the diatreme, together with complex systems of fracturing, acted as pathways for late hydrothermal fluids which caused alteration of volcanic material to sericite, chlorite and carbonate and precipitated ore minerals, quartz and calcite in the voids. Porosity and permeability were key factors in determining which portions of the layered diatreme were mineralized. The lower part of certain layers retained a relatively high porosity and were extensively mineralized. Metallic mineralization, consisting mostly of pyirte, sphalerite and arsenopyrite, is found as disseminations, tuff-breccia filling and veins.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.395-399
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• 2016

Background: Whether ambient exposure to environmental pollutants leads to hematopoietic malignancies such as multiple myeloma (MM) remains to be ascertained. Therefore, we aimed to investigate the immunotyping distribution of serum monoclonal paraprotein and the environmental influence on MM and monoclonal gammopathy of uncertain significance (MGUS) in the Taiwanese population. Materials and Methods: Serum protein electrophoresis with immunosubtraction by the capillary zone electrophoresis method was performed as primary screening for MM and MGUS. Clinical, pathological, and residence data of patients were also obtained. Results: From August, 2013 to June, 2015, a total of 327 patients underwent serum protein electrophoresis with immunosubtraction. Among these, 281 demonstrated no remarkable findings or non-malignant oligoclonal gammopathy, 23 were detected to have MGUS, 18 were identified as MM, and a further 5 were found as other malignancies. The most frequent immunotyping distribution of serum monoclonal paraprotein was IgG kappa (54.3%, n=25), followed by IgA lambda (15.2%, n=7) and IgG lambda (10.9%, n=5) in subjects with gammopathy. Additionally, it was shown that the elderly (OR: 4.61, 95% CI: 1.88-11.30, P<0.01) and males (OR: 2.04, 95% CI: 1.04-4.02, P=0.04) had significantly higher risk of developing MM and MGUS. There was no obvious impact of environmental factors on the health risk of MM and MGUS evolution (OR: 0.77, 95% CI: 0.40-1.50, P=0.49). Conclusions: The most frequent immunotyping distribution of serum monoclonal paraprotein included IgG kappa, IgA lambda and IgG lambda in MM and MGUS in the Taiwanese population. The elderly and male subjects are at significantly higher risk of MM and MGUS development, but there was no obvious impact of environmental factors on risk.

• Journal of Korean Neurosurgical Society
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• v.48 no.5
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• pp.391-398
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• 2010

Objective : This study was designed to validate the cell trafficking efficiency of the in vivo bioluminescence image (BLI) study in the setting of transplantation of the luciferase expressing bone marrow-derived mesenchymal stem cells (BMSC), which were delivered at each different time after transient middle cerebral artery occlusion (MCAO) in a mouse model. Methods : Transplanting donor BMSC were prepared by primary cell culture from transgenic mouse expressing luciferase (LUC). Transient focal infarcts were induced in 4-6-week-old male nude mice. The experiment mice were divided into five groups by the time of MSC transplantation : 1) sham-operation group, 2) 2-h group, 3) 1-day group, 4) 3-day group, and 5) 1-week group. BLI for detection of spatial distribution of transplanted MSC was performed by detecting emitted photons. Migration of the transplanted cells to the infarcted area was confirmed by histological examinations. Differences between groups were evaluated by paired t-test. Results : A focal spot of bioluminescence was observed at the injection site on the next day after transplantation by Signal intensity of bioluminescence. After 4 weeks, the mean signal intensities of 2-h, 1-day, 3-day, and 1-week group were $2.6{\times}10^7{\pm}7.4{\times}10^6$. $6.1{\times}10^6{\pm}1.2{\times}10^6$, $1.7{\times}10^6{\pm}4.4{\times}10^5$, and $8.9{\times}10^6{\pm}9.5{\times}10^5$, respectively. The 2-h group showed significantly higher signal intensity (p<0.01). The engrafted BMSC showed around the infarct border zones on immunohistochemical examination. The counts of LUC-positive cells revealed the highest number in the 2-h group, in agreement with the results of BLI experiments (p<0.01). Conclusion : In this study, the results suggested that the transplanted BMSC migrated to the infarct border zone in BLI study and the higher signal intensity of LUC-positive cells seen in 2 hrs after MSC transplantation in MCAO mouse model. In addition, noninvasive imaging in real time is an ideal method for tracking stem cell transplantation. This method can be widely applied to various research fields of cell transplantation therapy.

• Journal of the Korean association of regional geographers
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• v.23 no.2
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• pp.354-365
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• 2017

This study is to analyze the dual language and hybrid identity of the students of Daegu Chinese Middle.High School. Such a phenomenon is being produced and changed at the site or zone of meeting different or conflict factors such as Chinese and Korean. The Chinese Korean students had learned Korean from their mother and her relative at a young age, and their dual and complex language habit was produced due to the learning of Chinese from father and his relative. A large number of the students were educated at a Korean kindergarten, but they were formally learned Chinese and China's society and culture at a Korean Chinese school after primary school. The Chinese Korean students talk with parents, brother and sister, teacher, friend and neighbor at home, school and local by Chinese and/or Korean. They use a dual language of Chinese and Korean based on various situations, but they do not particularly distinguished both language in cognition. The students have a hybrid identity of simultaneously recognizing Chinese and Korean. But some of them think Chinese or Korean. It is necessary for the results of this study to be objectified from the following research on the students of Chinese Middle･High School in Seoul, Incheon and Busan.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.3
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• pp.102-118
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• 2010

Since hills are transitional area between plains and mountains, they are always under pressure to be developed. In the past, hills were recognized as areas that can be developed easily, but in the present they should be considered and preserved as forest resources. So far, little research has been done regarding cultivation status and transitional procedure. This study attempts to quantify changes in land use using time series data. To do so, this study has created a land use map for 1915, 1972, 2002 and 2006, and conducted a spatial analysis based on GIS. The research areas(the total size of the hills are 3,034 ha) are located in Chungcheongnam-do of South Korea. The size of the forest area of the hills in the research zone has decreased by 50% during the period of 1915 to 2006. The size of the reduced forest area after 2002 is similar to size of the reduced area that had taken place for the last 30 years before 2002. The reduction in forest area in the research area has led to increases in paddy field, upland field, artificial structures, and bare land. From 1915 to the late 1980s, hill development had been related to the primary industry and after the late 1980s, it has associated with the development of the secondary industry including industrial complex.

• Economic and Environmental Geology
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• v.42 no.3
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• pp.167-175
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• 2009

The geology of Sepola district in Mali is consisted of Birrimian group with metasedimentary rocks of lower Proterozoic and volcanoclastics, and later intrusive igneous rocks. Ore diposit in this district has the characteristics of vein- and disseminated-type gold deposit which was formed by infilling the secondary fracture zones related to the large-scale fault zone of NW direction within Birrimian group. It is confirmed as promising that Barani district has the gold grade of 0.53${\sim}$9.21 g/t with the extension of 1.3 km and width of 1 to 20.1 m. The ore mineralogy is simple with electrum, pyrite and galena. Fineness of gold grain ranges from 848 to 915(average 891) indicating mesothermal to hypothermal environment. Fluid inclusions are classified as liquid-rich type I. gas-rich type II and liquid-$CO_2$ bearing type III. Primary and pseudosecondary inclusions homogenize from 236 to 393$^{\circ}C$ with salinity of 0.0 to 8.6 wt% NaCl. Secondary inclusions homogenize from 103 to 184$^{\circ}C$ with salinity of 0.7 to 8.6 wt.%. From the relationship between homogeniztion temperature and salinity, it may be thought that auriferous fluid experienced dilution and cooling through inflow of meteoric water after fluid unmixing derived from pressure decrease in the temperature range of 400 to 250$^{\circ}C$. From the massive occurrence of quartz vein, simple mineralogy with paucity of sulfide, and presence of liquid-$CO_2$ bearing with high homogenization temperature, it is thought that gold mineralization in Sepola district correspods to the mesothermal to hypothermal ore deposit.

• Parasites, Hosts and Diseases
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• v.48 no.3
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• pp.237-243
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• 2010

Comprehensive quarterly serosurveillance on scrub typhus in small mammals collected from military training sites located near the Demilitarized Zone (DMZ), northern Gyeonggi-do (Province), ROK was conducted to determine the potential rodent-borne and associated ectoparasite disease risks to military personnel. A total of 1,196 rodents and insectivores representing 8 species, Apodemus agrarius (87.3%, n = 1,044), Mus musculus (5.4%, n = 65), Crocidura lasiura (3.3%, n = 40), Microtus fortis (2.6%, n = 31), Micromys minutus (0.3%, n = 4), Tscherskia triton (0.3%, n = 4), Rattus norvegicus (0.3%, n = 4), and Myodes regulus (0.3%, n = 4) were assayed for the presence of antibodies to Orientia tsutsugamushi. O. tsutsugamushi antibodies were detected in 6 of 8 species and seroprevalence determined; A. agrarius (45.6%), M. musculus (23.1%), M. fortis (48.4%), M. minutus (50.0%), T. triton (50.0%), and R. norvegicus (25.0%). A total of 31,184 chigger mites collected from 508 rodents and insectivores were slide-mounted and 10 species belonging to 4 genera were identified. Leptotrombidium pallidum (53.4%) was the most frequently collected, followed by L. pal pale (15.7%), Neotrombicula tam/yai (14.3%), L. orientate (10.7%), L. zetum (3.1%), Walchia fragilis (2.1%), and L. gemiticutum (0.8%), while the remaining 3 species, L subintennedium, N. gardellai, and Euschoengastia koreaensis were rarely observed (prevalence < 10%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4), L. orientale (45.0), and L. palpate (21.4), were observed during the spring season.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.153-153
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• 2010

Recently, to develop GaN-based light-emitting diodes (LEDs) with better performances, various approaches have been suggested by many research groups. In particular, using the patterned sapphire substrate technique has shown the improvement in both internal quantum efficiency and light extraction properties of GaN-based LEDs. In this paper, we discuss the influences of the direction of the hexagonal-structure arrays of lens-shaped patterns (HSAPs) formed on sapphire substrates on the crystal, optical, and electrical properties of InGaN/GaN multi-quantum-well (MQW) LEDs. The basic direction of the HSAPs is normal (HSAPN) with respect to the primary flat zone of a c-plane sapphire substrate. Another HSAP tilted by 30o (HSAP30) from the HSAPN structure was used to investigate the effects of the pattern direction. The full width at half maximums (FWHMs) of the double-crystal x-ray diffraction (DCXRD) spectrum for the (0002) and (1-102) planes of the HSAPN are 320.4 and 381.6 arcsecs., respectively, which are relatively narrower compared to those of the HSP30. The photoluminescence intensity for the HSAPN structure was ~1.2 times stronger than that for the HSAP30. From the electroluminescence (EL) measurements, the intensity for both structures are almost similar. In addition, the effects of the area of the individual lens pattern consisting of the hexagonal-structure arrays are discussed using the concept of the planar area fraction (PAF) defined as the following equation; PAF = [1-(patterns area/total unit areas)] For the relatively small PAF region up to 0.494, the influences of the HSAP direction on the LED characteristics were significant. However, the direction effects of the HSAP became small with increasing the PAF.

• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.343-359
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• 2013

In order to understand shoreline environment characteristics of Korean reservoirs, the interrelationships between environmental factors of geomorphology, hydrology, water quality and shoreline soil were analyzed, and the reservoir types were classified according to their environmental characteristics in the 35 reservoirs selected by considering the purpose of dam operations and annual water-level fluctuations. Geomorphological and hydrological characteristics of reservoirs were correlated with the altitude and the size scale of reservoirs. The annual range of water level fluctuation showed a wide variation from 1 m to 27 m in the various reservoirs in Korea. The levels of eutrophication of most reservoirs were mesotrophic or eutrophic. From the result of the soil texture analysis, sand contents were high in reservoir shorelines. Range, frequency and duration of water-level fluctuation were distinctive from the primary function of reservoirs. Flood control reservoirs had a wide range with low frequency and waterpower generation reservoirs had a narrow range with high frequency in the water-level fluctuation. According to the result of CART (classification and regression tree) analysis, the water quality of reservoirs was classified by water depth, range of water-level fluctuation and altitude. The result of PCA (principal component analysis) showed that the type of reservoirs was classified by reservoir size, water-level fluctuation, water quality, soil texture and soil organic matter. In conclusion, reservoir size, the water-level fluctuation, water quality and soil characteristics might be major factors in the environment of reservoir shorelines in Korea.

• Journal of Fisheries and Marine Sciences Education
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• v.9 no.1
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• pp.1-30
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• 1997

The results of this study were summarized as follows : 1. In the field of general subjects, the compulsory courses are composed of 10 courses(14.3%) in 9 subjects and show only one course in one subject in Korea, while those in Japan are composed of 11-12 courses(18.3-20.0%) in 8 subjects and present each level course of primary and deepening in course. 2. In the field of general subjects, the elective courses are composed of 60 courses(85.7%) in 12 subjects in Korea, while those in Japan are composed of 48-49 courses in 8 subjects. 3. In the field of specialized subjects, the compulsory courses for streams have 3 courses(10.7%) in Korea, while those in Japan have 4 courses (16.7%) 4. In the field of specialized subjects, the compulsory courses for departments are composed of 2-4 courses in Korea, while specialized courses for departments are composed of 4 courses in Japan. 5. In the field of general subjects, unit allotment of the compulsory courses requires the completion of 70 units (37.2%) out of total 188 units(excluding extracurricular activites) in Korea, while that in Japan requires the completion of 70-90 units(38.9-50.0%) out of total 180 units (excluding extracurricular activites). 6. In the field of general subjects, unit allotment of the elective courses requires the completion of 12-36 units(6.4-19.2%) out of total 188 units in Korea, while that in Japan requires the completion of30-50 units(16.7-27.8%) out of total 180 units. 7. In the field of specialized subjects, unit allotment of the major courses requires the completion of more thar 82 units in Korea, while that in Japan requires the completion of more than 60 units, so that the units of the complusory courses for stresms of both of the countries tend to show many differences and diversity in both zone and school. Based on these results, the research concluded that the Fisheries High Schools in the two countries make up nearly similar curricula, while in Japan general subjects carry more extensive choice of courses and higher unit allotment is provided for general subjects than in Korea. It was also concluded that the curriculum for vocational education in Japan intends to develop spontaneous, creative, and soft personalities for job. This study suggests that Fisheries High School curriculum in Korea needs to be improved to give students more opportunities for course selection and to help students adapt themselves to various kinds of job groups.