• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.89-112
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• 2012

The Korean Peninsula consists of three Precambrian blocks: Nangrim, Gyeonggi and Yeongnam massifs. Here we revisited previous stratigraphic relationships, largely based on new geochronologic data, and investigated the crustal evolution history of the Precambrian massifs. The Precambrian strata have been usually divided into lower crystalline basements and upper supracrustal rocks. The former has been considered as Archean or Paleoproterozoic in age, whereas the latter as Paleoproterozoic or later. However, both are revealed as the Paleoproterozoic (2.3-1.8 Ga) strata as a whole, and Archean strata are very limited in the Korean Peninsula. These make the previous stratigraphic system wrong and require reconsideration. The oldest age of the basement rocks can be dated as old as Paleoarchean, suggested by the occurrence of ~3.6 Ga inherited zircon. However, most of crust-forming materials were extracted from mantle around ~2.7 Ga, and produced major portions of crust materials at ~2.5 Ga, which make each massif a discrete continental mass. After that, all the massifs belonged to continental margin orogen during the Paleoproterozoic time, and experienced repeated intracrustal differentiation. After the final cratonization occurring at ~1.9-1.8 Ga, they were stabilized as continental platforms. The Nangrim and Gyeonggi massif included local sedimentary deposition as well as igneous activity during Meso-to Neoproterozoic, but the Yeongnam massif remained stable before the development of Paleozoic basin.

• Korean journal of communication and information
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• v.45
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• pp.7-48
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• 2009

The recent crises of Marxism do not mean Marx’s crisis. Marx said that he was not a Marxist. The purposes of this essay explore (1) the modern identity of the political economy; (2) the possibilities of mutual understanding between neoclassical economics and Marxist economics; (3) problems of the political economy in media and communication industry. I have begged for analytical Marxists, because of their good fruits. They accepted the methods of modern social science and they constituted a tremendous advance in the application of the scientific methods to the study of society. In insisting on micro-foundations(methodological individualism), analytical Marxism distinguished itself from structuralism and functionalism. I appreciate that analytical Marxism has reduced a theory to practice. But the works didn’t listen to everyone(from Marxists to un-Marxists), and explain everything. Making theory with production/consumption, macro/micro, and structure/behavior is a road to the political economy in the long run. It also applies to media and communication industry. The realm of media/communication is broad, which in philosophy, humanities, politics, economics, sociology, and engineering. And media policy is more complicated by politicians who look at the same situation from different angles. By the aid of interdisciplinary research, the political economy of media/communication shall explain at full length.

• Tuberculosis and Respiratory Diseases
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• v.58 no.5
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• pp.459-464
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• 2005

연구 배경 : Adenosine deaminase (ADA)는 퓨린 (purine) 대사에 작용하는 효소로서 림 프구, 특히 T-림프구의 증식과 분화에 관여하며, 결핵성 흉수의 진단에 있어서 중요한 생화학적 표지자 중의 하나이다. 한편, 노인의 경우, T-림프구의 수와 기능의 감소에 의하여 면역 기능이 감소하는 것으로 알려져 있다. 이에 저자 등은 노인 결핵성 흉수 환자에서 흉수내의 ADA 수치가 젊은 환자에서보다 감소하는지를 조사하였다. 방 법 : 4년 동안 세브란스 병원에서 1) 흉수 결핵균 배양 양성 또는 2) 흉막 조직 검사상 결핵에 합당한 소견을 보여 결핵성 흉수로 진단받은 환자 80명을 대상으로 후향적으로 조사하였다. 65세를 기준으로 두 군으로 분류하였으며, 연령과 흉수 ADA 수치의 연관 관계를 독립 표본 t-검정 및 선형 회귀 분석을 이용하여 연구하였다. 결 과 : 80명의 환자 중 65세 이상은 21명 (26.3%)이었다. 흉수 내의 ADA 수치는 65세 이상 및 이하 군에서 각각 $71.2{\pm}27.6IU/L$, $68.5{\pm}5.8IU/L$ 이었다 (p=0.69). 선형 회귀 분석에서도 연령과 흉수 내의 ADA 수치는 상관 관계를 보이지 않았다 ($r^2=0.05$, p=0.59). 결 론 : 본 연구의 결과에 의하면, 결핵성 흉수의 진단에서 흉수 ADA 수치를 보조 지표로 사용하는 데 있어서, 노인환자에서도 젊은 환자와 동일한 임상적 유의성을 가지고 동일한 결정 수치 (cut-off value)를 적용할 수 있을 것으로 판단된다.

• Research in Plant Disease
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• v.22 no.4
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• pp.289-292
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• 2016

We surveyed the occurrence of Japanese yam mosaic virus (JYMV) on Yam in Gyeongsangbukdo pronvince from 2013 to 2015. The symptoms of JYMV were yellow stripes and chlorosis in yam leaves and the infection rate was ranged from 33.6% to 40.8%. We determined nucleotide sequence encoding the polyprotein of JYMV isolate BRI from yam leaves using next-generation sequencing (NGS) method. The partial nucleotide portion (7,736 nucleotides) of the genomic RNA of the JYMV isolate BRI has been sequenced (accession No. KU309315). The region sequenced includes a single open reading frame (ORF) encoding a polyprotein composed of 2,497 amino acids containing the coat protein (CP) and 3' untranslated region (UTR). The genomic organization of this isolate shows almost the same to that of other members of JYMV. The JYMV isolate BRI showed 77% to 79% nucleotide identity with the Japanese and Chinese strains and isolates. This is the first report of the genome nucleotide sequence of JYMV from Dioscorea opposita in Korea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.1
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• pp.27-34
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• 2001

To investigate the processes governing the distribution of elements in the tidal flat, thirty-eight sediment samples collected from the Saemangeum tidal flat of the Korean west coast were analyzed for their contents of major (Al, Fe, Mg, Ca, Na, K, Ti) and trace (P, Mn, Ba, Sr, V, Cr, Co, Cu, Ni, Zn, Pb) elements. Most elements showed generally lower contents compared to data published for other tidal flats of Korea, and the effect of anthropogenic input could not be recognized in the sediments. The relative abundance and distribution of most of the elements varied significantly with the grain size of sediments. High contents of Al, Fe, Mg, Ti, P, Mn, V, Co, Cr, Cu, Ni and Zn were found in the finer sediments in the upper tidal flat of the study area, suggesting that tidal sedimentation processes play an important role in controlling the distribution of these elements. However, sediment grain size does not impose any significant effect on the abundance and distribution of Ca, Na, K, Ba, Sr and Pb. It appears that the clastic mineralogy in the coarse-grained fractions is the dominant factor determining the distribution of these elements in the study area.

• The Journal of the Petrological Society of Korea
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• v.12 no.1
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• pp.32-52
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• 2003

The Mt. Baegyang in Busan, composed of sedimentary basement rocks (Icheonri Formation), andesite (lava), andesitic pyroclastic rocks, fallout tuff and tuffaceous sedimentary rocks, rhyolitic pyroclastic rocks, intrusive rocks (granite-porphyry, felsite, and biotite-granite) of Cretaceous age in ascending order. The volcanic rocks show a section of composite volcano which comprised alternation of andesitic lava and pyroclasitc rocks, rhyolitic pyrocalstic rocks (tuff breccia, lapilli tuff, fine tuff) from the lower to the upper strata. From the major element chemical analysis, the volcanic and intrusive rocks belong to calc-alkaline rock series. The trace element composition and REE patterns of volcanic and plutonic rocks, which are characterized by a high LILE/HFSE ratio and enrichments in LREE, suggest that they are typical of continental margin arc calc-alkaline rocks produced in the subduction environment. Primary basaltic magma might have been derived from partial melting of mantle wedge in the upper mantle under destructive plate margin. Crystallization differentiation of the basaltic magma would have produced the calc-alkaline andesitic magma. And the felsic rhyolitic magma seems to have been evolved from andesitic magma with crystallization differentiation of plagioclase, pyroxene, and hornblende.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.1031-1040
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• 2015

Ultrstructural studies of germ cell differentiation and vitellogenesis in the oocytes of the female Rapana venosa in the brackish water area of Seomjin River were investigated by transmission electron microscope observations. In the early vitellogenic oocytes, the Golgi complex and mitochondria were involved in the formation of glycogen particle, lipid droplets, and yolk granules. In the late vitellogenic oocytes, the rough endoplasmic reticulum and multivesicular bodies were involved in the formation of proteid yolk granules in the cytoplasm. However, heterosynthetic vitellogenesis in this species were not observed in vitellogenic oocytes during oogenesis. A mature yolk granule was composed of three components: crystalline core, electron lucent cortex and the limiting membrane. As shown in some large gastropods, vitellogenesis in R. venosa occurred by way of endogenous autosynthesis without heterosythetic vitellogenesis (exogeneous endocytosis), which are found in the oocytes in bivalves. The mating period and spawning activity were related with the increases of seawater temperatures and salinities.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.658-662
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• 2013

Rubus coreanus and Astragalus membranaceus Bunge have been used as a traditional medicine with various pharmacological properties for a long time in Asia. We investigated the proliferative and differentiative effects on osteoblastic cells, MG-63 in various mixture ratios of immature fructus extracts of R. coreanus and root extracts of A. membranaceus. With preliminary in vivo ovariectomized mice, we confirmed the effects of the supplementation of various mixture on alkaline phosphatase (ALP) activity in serum. The ratio of 7:3 is considered as the most effective ratio for the proliferation of osteoblastic cells as they increased by 56.8% similar to estradiol. ALP activity in osteoblast increased by the combination of R. coreanus and A. membranaceus and peaked in the ratio of 72:28 and 68:32 respectively. These results indicate that the optimal combination of R. coreanus and A. membranaceus in 7:3 has the most beneficial effects on the activation of osteoblast cells, and give further possibilities that it can be used clinically in the treatment of osteoporosis.

• Korean Journal of Plant Taxonomy
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• v.37 no.3
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• pp.275-308
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• 2007

For 20 taxa of Korean Allium, including 16 species and 5 varieties, examined were morphological characters (i.e. sexuality, structure and shape of underground part, types and growing patterns of leaf and scape, and shapes of perianth, filament and pistil). The specialization and the evolutionary trends of taxonomic characters were inferred from morphological examination. Taxonomic relationships and system of Korean Allium were also studied. The characters showing evolutionary trends were the structure and shape of underground part including rhizome and bulb, leaf, scape, inflorescens, filament and ovary. It seemed that thin and short rhizome developed from thick and long one, and the membranous simple bulb tunic evolved into fibrous reticulate one. The presence of hyaline sheath in A. monanthum of sect. Microscordum was apomorphic. Both angular leaf blade with 2-rowed vascular bundle and flat blade with 1-rowed vascular bundle were developed from terete one with 2-rowed vascular bundle. The base of filament have differentiated from entire to toothed, and 2-ovuled ovary as well as erect scape before flowering was plesiomorphic type. In addition, sexuality, structure of underground part, the presence of hyaline sheath and cross-section structure of leaf were taxonomic characters with the level of the subgenus in this genus. Shape of rhizome, bulb, leaf, scape and pedicel discriminated each section from other ones in the subgenera easily. The shape and arrangement of perianth and filaments were the diagnostic characters for species level along with shape of ovary and stigma.

• Korean journal of applied entomology
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• v.39 no.1
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• pp.43-52
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• 2000

A portion of mitochondria1 COI gene (438 bp) was sequenced from the sampls of Plutella xylostella from four localities in Korea to investigate the population genetic structure and characteristics by measuring the magnitude of genetic diversity and the degree of gene flow among populations. Thirteen haplotypes ranging in nucleotide divergence 0.3% to 1.4%, were obtained from 21 individuals. The nucleotide divergence was similar to the other related studies, but haplotype diversity was substantially higher (mean h = 0.81). The genetic distance among geographically remote Cheju Island population and the two Kimhae populations, distant 1 lkm to each other, was not statistically significant (p<0.05). Instead, a substantial or high female gene flow was detected (Nm = 2-30). One Hawaiian haplotype of the diamondback moth obtained through GenBank search also was genetically similar to the ones obtained from this study. Collectively, the genetic population structure of the diamondback moth in Korea can be characterized into two aspects. First, the diamondback moths in Korea possesses overall moderate genetic divergence based on a high number of haplotypes. Second, a high haplotype diversity within each population due to the long distance dispersal with a substantial dispersal power and the resultant genetic similarity among geographic populations is characteristic.