• Journal of Life Science
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• v.26 no.12
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• pp.1355-1359
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• 2016

Human bone marrow mesenchymal stem cells (hBM-MSCs) can differentiate into various cell types including osteoblasts, adipocytes, chondrocytes, and myocytes. Previous studies, including our own, have shown that MSCs can also differentiate into neuron-like cells. However, their rate of neuronal differentiation is not sufficient for application to stem cell therapy, which requires well-defined cell types. For this purpose, we first examined the expression of neuronal lineage markers (GFAP, MAP-2, KCNH1, Nestin, NF-M, and Tuj-1) by real-time PCR, western blot, and immunocytochemical staining. The expressions of the astrocyte marker GFAP and neuronal markers NF-M and Tuj-1 increased in neuronal differentiated MSCs (dMSCs). To improve the neuronal differentiation efficiency, PDE4, an important signaling intermediator in the progression of neuronal differentiation, was modulated using well-known inhibitors such as rolipram or resveratrol and then differentiated into neuronal cells (Roli- or RSV-dMSCs). The expressions of NF-M, Tuj-1 were increased while that of GFAP decreased in Roli- and RSV-dMSCs, which were examined by real-time PCR, western blot, and immunocytochemical staining. From these experiments, we have found that the neuronal differentiation efficiency can be ameliorated by the modulation of PDE4 activity.

• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.616-631
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• 2007

Residential differentiation is an academic theme which has been given enormous attention in urban studies. This is due to the fact that residential segregation can be seen as one of the best indicators for socio-spatial dialectics occurring on urban space. Measuring how one population group is differentiated from the other group in terms of residential space has been a focal point in the residential segregation studies. The index of dissimilarity has been the most extensively used one. Despite its popularity, however, it has been accused of inability to capture the degree of spatial clustering that unevenly distributed population groups usually display. Further, the spatial indices of segregation which have been introduced to edify the problems of the index of dissimilarity also have some drawbacks: significance testing methods have never been provided; recent advances in spatial statistics have not been extensively exploited. Thus, the main purpose of the research is to devise a spatial separation measure which is expected to gauge not only how unevenly two population groups are distributed over urban space, but also how much the uneven distributions are spatially clustered (spatial dependence). The main results are as follows. First, a new measure is developed by integrating spatial association measures and spatial chi-square statistics. A significance testing method based on the generalized randomization test is also provided. Second, a case study of residential differentiation among groups by educational attainment in major Korean metropolitan cities clearly shows the applicability of the analytical framework presented in the paper.

• Economic and Environmental Geology
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• v.54 no.2
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• pp.187-197
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• 2021

The Hyeongjeseom (Islet) is an erosional remnant of volcano which is located about 2 km northeast of sea shore of the Songaksan tuff ring, and is composed of volcaniclastic deposit, agglomerate and scoria deposit, ponded lava, aa lava flows, reworked deposit and beach deposit in ascending order from the base. The volcano is formed by volcaniclastic deposits and lava flows that recorded a transition from initial phreatomagmatic to magmatic explosions followed by lava effusion. It is interpreted that the outcropped volcaniclastic deposit may be a remaining portion of outer ring of a tuff cone. A bomb and a ponded lava yield geochemically basaltic trachyandesite compositions (SiO2 51.3 wt%, Na2O+K2O 6.0 wt%) and belong to olivine basalt with scarce (<5 %) phenocrysts of olivine, petrographically. By incremental heating Ar-Ar dating method, the plateau age of lava flow in the Heongjesom is 9.2±3.6(2σ) ka, implying that the volcanism of Heongjeseom may have occurred earlier than the Songaksan tuff ring which erupted ca. 3.7 ka. It still remains a task to find a volcano which matches with a historical record of volcanic activity that occurred a thousand years ago.

• The Journal of the Petrological Society of Korea
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• v.5 no.2
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• pp.135-141
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• 1996

La-Ce method is one of new geochronological methods developed recently. La and Ce are one of the rare earth elements, and, with Sm-Nd system. La-Ce system is very useful in understanding the evolution processes of crust and mantle. In this paper, I introduce the basic concept of the La-Ce method, and apply it in clarifying LREE pattern of source material of leuco-granitic gneisses from the Imweon area, Kangwon-do, and K-rich granite from the Anshan area in Liaoning Province, NE China. Sm-Nd data on the Anshan K-rich granites give an age of $3.16{\pm}0.06$ Ga($2{\sigma}$), with initial $^{143}Nd/^{144}Nd$=$0.50846{\pm}0.00005$ (${\epsilon}_{Nd}$=-1.5). On the basis of Ce and Nd isotopic ratio, leucogranitic gneiss and K-rich granite has been fractionated from the source material which had had similar to CHUR (chundritic uniform reservoir). And the initial ${\epsilon}_{Nd}$ value suggest that the crustal formation age of the Liaoning Province area, NE China was early Archean.

• Land and Housing Review
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• v.11 no.2
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• pp.47-57
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• 2020

In this study, we aimed to identify the latest trends of landscape in apartment complexes by identifying how landscaping spaces are being created and what their characteristics are. Furthermore, we aimed to find out what type of garden is being constructed in the landscaping space and what the difference between the landscaping space and the garden space is, and to define the future direction of landscape for apartment complexes. The following results were our findings. First, we identified that landscaping space is divided into general landscaping space and garden space. The garden space has designated area within the whole apartment complex as a garden and there is a variety of garden themes and plants, facilities, packaging patterns, and sculptures are used accordingly. On the other hands general landscaping space features uniform patterns of packaging and simple planting patterns. Our finding is that the current trend is to set up separate garden space within the landscaping space of apartment complexes. Although gardens are often regarded as personal property and spaces that need to be cultivated or managed, and spaces that are limited to fences are defined as gardens, the current landscaping space of apartments is creating gardens-like spaces within public spaces.

• Clinical and Experimental Pediatrics
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• v.49 no.10
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• pp.1100-1105
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• 2006

Purpose : Because NELL2 expression is strictly restricted only in neurons in developing and post-differentiated neural tissues, it is thought to be involved in the neuronal differentiation during development and in the maintenance of neuronal physiology in the post-differentiated neurons. In this study, we examined whether NELL2 is involved in the regulation of cell cycle and apoptosis in the hippocampal neuroprogenitor HiB5 cells. Methods : Effects of NELL2 on the cultured HiB5 cell numbers, DNA fragmentation, and proteins involved in the regulation of the cell cycle were measured. Results : NELL2 induced a decrease in cell numbers and an increase in G1 phase arrest. Moreover, transfection of NELL2 resulted in an increase of DNA fragmentation that shows an evidence of apoptosis. Contents of proteins involved in the regulation of cell cycle were also changed by transfection of NELL2 expression vectors. Conclusion : This study suggests that NELL2 plays an important role in the regulation of cell cycle and apoptosis of neurons.

• Tuberculosis and Respiratory Diseases
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• v.59 no.6
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• pp.631-637
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• 2005

Background : Transcriptional factors of the CREB(cAMP Response Element Binding Protein) are involved in the regulation of gene expression in response to a variety of signaling pathways. Proteins produced by the CREB genes play key roles in many physiological processes, including memory and long-term potentiation. The retinoic acid receptor (RAR) axis mediates epithelial cell differentiation and proliferation in many tissues including the lung. Material and method : The RAR and CREB expression levels were examined in 60 adenocarcinomas and 60 squamous cell carcinomas of the lung using immunohistochemical staining. Results : 1) RAR protein expression was found in 58.3%(35/60) of adenocarcinomas and 36.7%(22/60) of squamous cell carcinomas(P<0.05). 2) RAR protein expression was found in 80%(16/20) of well differentiated adenocarcinomas, 60%(12/20) of moderately differentiated adenocarcinomas, and 35%(7/20) of poorly differentiated adenocarcinomas (P<0.01). 3) RAR protein expression was found in 45%(9/20) of well differentiated squamous cell carcinomas, 35%(7/20) of moderately differentiated squamous cell carcinomas, and 30%(6/20) of poorly differentiated squamous cell carcinomas (P>0.05). 4) CREB expression was found in 61.7%(37/60) of adenocarcinomas and 40%(24/60) of squamous cell carcinomas( P<0.05). 5) CREB expression was found in 85%(17/20) of well differentiated adenocarcinomas, 60%(12/20) of moderately differentiated adenocarcinomas, and 40%(8/20) of poorly differentiated adenocarcinomas (P<0.01). 6) CREB expression was found in 45%(9/20) of well differentiated squamous cell carcinomas, 35%(7/20) of moderately differentiated squamous cell carcinomas, and 35%(8/20) of poorly differentiated squamous cell carcinomas(P>0.05). 7) RAR and CREB expression was found in 68.5% of lung cancers, and there was a significant correlation between them(P<0.05). Conclusion : RAR and CREB expression can be used to indirectly determine the malignant potentiality of a cell.

• Journal of the Korean Geographical Society
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• v.32 no.4
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• pp.527-540
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• 1997

이 글에서는 해외지역연구에 있어 세계와와 관련한 여건 변화, 지리하계의 동향, 그리고 21세기의 새로운 지역연구에 지리학의 역할이 어떠하여야 할 것인가를 살피고자 한다. 해외지역연구는 2차대전 이후 미국을 중심으로 발달하였다. 냉전기에 세계적 우위를 유지하고 국익을 보호하기 위하여 외국 현지어 구사 능력을 포함한 해외 정보 수요가 늘어 지역연구의 발달을 보게 된 것이다. 이러한 배경 때문에 지역연구는 개성기술적(ideographic)성격을 띠게 되었다. 요즘에는, 지역연구가 주로 초국적기업, 국제 경영대학원 등을 중심으로 이루어 지고 있다. 새 지역연구는 해외시장정보 수집 등 경제적 동기로 이루어지고 있어, 경제적으로 편향되는 취약점이 있다. 세계화는 요즘 하계의 화두(話頭)로, 세계 경제와 사회에 일고 있는 이 변화를 바로 이해하는 것은 향후 지역연구의 방향을 정립하는데 매우 중요하다. 세계화는 세계 어디서나 똑같이 일어나는 동질적인 현상이 아니라, 매우 다양하고 여러 의미가 담긴 현상이다. 마치 동전에 양면이 있듯이, 세계화는 수렴과 분화를 동시에 일으키고 있는 것이다. 따라서, 국경을 개방하고 장애를 없애 하나의 동질적인 세계시장환경을 지향하는 신자유경제 논리에 바탕한 지역연구는 설득력이 약하다. 지리학이 지역연구에 기여하기 위해서는 다음과 같은 노력이 계속되어야 한다. 첫째, 해외지역을 이해하려면 공간(space)과 장소(place)연구가 필수적이라는 점을 인식하고, 둘째, 인간과 환경의 상호작용 관점에서 지리적 차이를 파악하려는 노력이 필요하다. 셋째, 지리학은 이론정립 노력을 계속해야 하며, 넷째, 그 이론들은 해외지역의 현장답사와 정보수집을 통하여 검증되어야 한다. 지리학은 일찍부터 도시, 농촌 등 미시적 수준의 연구를 수행해왔기 때문에 경험적 연구에 강하다. 다섯째, 정부와 기업 등 조직에 대한 지리학적 연구가 이루어져야 할 것이다. 경제활동 분포에 대한 조직의 역할, 소유권에 대한 정부의 규제, 생산 조직의 환경 영향 등의 연구가 그 예이다. 여섯째, 지리학의 발달을 위하여 국가, 국제적 학술 기구를 활용하는 전략이 필요하다. 국제지리학연합(IGU)에서 개발한 지리교육과정, 미국National Research Council에서 세계지리에 밝지 못한 국민을 대상으로 펴낸 지리서 등이 그 사례이다. 지역연구는 사회과학 이론과 문화연구가 서로 접목되도록 새롭게 방향이 설정되어야 하며, 지리학의 인간-환경 연구 전통이 여기에 기여할 수 있을 것이다. 그러나 지리학의 역할이 효율적이기 위해서는 지리학 자체의 담론을 다시 확립해야 한다. 지리학계에서 지난 20여년간 추구해왔듯이 일반적 법칙을 지향(nomothetic)하는 접근법을 활용해야 하며, 여타 사회과학 및 환경과학과도 긴밀한 관련을 유지할 필요가 있는 것이다.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1994.07a
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• pp.23-24
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• 1994

본 연구는 성숙과의 저장중에 세포벽분해효소가 세포벽을 분해해서 물성의 변화를 유발함으로 일어나는 과실의 연과가 품질과 저장성의 저하 뿐만 아니라 영양적, 경제적 손실을 초래한다는 점을 고려하여 대추의 성숙중에 일어나는 연화현상을 연구하고자 성숙에 따른 경도, 세포벽분해효소의 활성, 세포벽 다당류 pectin질, 비섬유성 중성당 및 조직의 변화를 조사하였다. 경도는 대추의 숙성에 따라 감소하였고, polygalacturonase와 $\beta$-galactosidase의 활성은 각각 변색기와 완숙기에 나타난 이후 급격히 증가하였다. 세포벽 다당류인 pectin질과 알칼리 지용성 hemicellulose는 완숙기가지 증가햐였으나 cellulose는 완숙기에 산가용성 hemicellulose와 cellulose를 제외한 세포벽 다당류의 함량은 다소 감소하였다. 대추의 세포벽 비섬유성 중성당으로 rhamnose, arabinose, xylose, mannose, galactose, glucose가 동정되었고, 성숙동안에 pectin질에서는 arabinose, mannose, galactose와 총 비섬유성 중성당의 함량이 감소하였고, 산가용성 hemicellulose에서는 xylose와 mannose가 뚜렸하게 증가하였으나 중성당은 변화없었으며, 알칼리 가용성 hemicellulose에서는 성숙에 따른 변화가 거의 없었다. pectin질의 경우 수용성 pectin, EDTA 용해성 pectin 및 총 pectin은 성숙중에 증가하는 경향이있으나 불용성 pectin은 감소하는 경향이였으며 과숙기에는 불용성 psctin EDTA용해성 pectin 및 총 pectin의 함량은 모두 현저히 감소하였다. 대추의 성숙중 조직에서는 pectin질로 구성된 중충의 붕괴현상이 뚜렸하게 나타났다.발이 절실히 필요한 실정이다. 이러한 배경으로 본 강연에서는 효소적갈변 저해제의 개발과 그들의 식품가공에의 적용 현환 및 화장품, 의약품으로의 응용에 대해 설명하고자 한다.L주에 비해 S주는 수정후 용과가 더 심하다. 9) 화분관의 행동은 수정력과 완전히 일치된다. 즉 L-selfing, $L{\times}L$, S-selfing, $S{\times}S$등의 부적법 수분에서는 화분관은 화주의 미중에서 정지되지만 $L{\times}S$, $S{\times}L$,에서는 수분 약 40-50분 후이면 화분관은 자방까지 도달된다. 10) S주는 웅본으로 오인되어 있지만 인위적법수분을 하면 수정력이나 화분관의 행동은 L주에서와 동일하다. 11) S화분은 완전하지만 L화분은 약 70%가 내용공허한 Adortive pollen 이다. 12) L화분중 나머지 30%도 S화분에 비해서 염색도가 낮은것이 많고 S화분 같이 농염되는 것은 극히 소수이다. 13) 본장물은 분화가 고도로 진행된 전형적인 이형예작물이여 마치 Dimorphism 에서 Dioecious 에로 이행되는 수가 있다는 것을 표시하는 증거가 되는 것 같다. 다소 높은 산소농도 3%~5% 이산화탄소 농도 5~8%에서 저장하는 것이 효과적일 것으로 판단되었다.철쭉군목으로 대표되나 군단이 하의 군목들은 다소 차이를 보이는 것으로 나타났다. 중간상인이론의 수정이 필요하다고 본다.가\ulcorner 본 논문에서는 표면적 형태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$ elements)로 가정한다. 즉, [+wh] 의미의 겹의문사는 동일한 구성요 소를 지닌 병렬적 합성어([

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.779-788
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• 2005

Purpose : Echinacea, a traditional plant medicine has been used as immune-stimulant. Recent studies have revealed that extract of Echinacea has immunostimulatory effects on human blood mononuclear cells. This study was designed for the purpose of screening the genes associated with immunologic effects of Echinacea on monocytes and dendritic cells using a cDNA microarray chip. Methods : $CD14^+$ monocyte cells were cultured for one day with Echinacea extract(final concentration : $50{\mu}g/mL$) in experiment 1, but were cultured without Echinacea in experiment 2. The gene expression of these cultured monocytes was analyzed using the cDNA microarray chip. Dendritic cells produced from $CD14^+$ monocyte were cultured for five days with GM-CSF and IL-4, and then cultured for one day with Echinacea in experiment 3, but were done without Echinacea in experiment 4. Results : In experiments 1 and 2, there were 17 significantly expressed genes with average expression ratios above 2.5, including interferon gamma-inducible protein 30(IFI 30), CDC(cell-division-cylcle)-like kinase 2(CLK 2), syndecan binding protein(syntenin), superoxide dismutase 2, etc. In experiments 3 and 4, there were 24 gene, with significantly expressed genes were 24 genes, which were insulin-like growth factor 2(somatomedin A), methyl-CpG binding domain protein 3, IFI 30, small inducible cytokine subfamily A, member 22, etc. The genes encoding CD44, IFI 30, mannose receptor C type 1(MRC 1), chemokine receptor 7(CCR 7), CLK 2, syntenin and cytochrome C oxidase subunit VIII were significantly expressed in both monocytes and dendritic cells cultured with Echinacea. Conclusion : This study employed a cDNA microarray chip to elicit the immune-associated gene profile; the expression was enhanced by Echinacea in CD14+ monocytes and dendritic cells. Thus we laid the basis for the quantitative and functional analysis of genes induced by Echinacea in monocytes and monocyte-derived dendritic cells.