• Journal of the Korean association of regional geographers
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• v.22 no.1
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• pp.120-134
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• 2016

This study aims to investigate the hierarchical stepwise migration and its influences on regions (metropolitan areas, cities and counties of Korea administrative district) through analyzing the city rank-size and the changes of natural increase of population. The result shows that the inter-regional migration has been associated to the decrease of the population and the decline of NIR in the regions where outflows have been persisted. Also, theses demographic events have sequentially occurred through the hierarchy of settlement system: gradually from rural (gun) and lower ranked regions in the system of city rank-size, to urban (si) and regions in the high ranks in the system. Based on the result of this study, it is possible to understand and expect the major origins of inter-regional migration, the presence of the hierarchical stepwise migration and most significantly, the spatial expansion of depopulation problems.

• Journal of the Korean Society of Visualization
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• v.16 no.2
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• pp.38-44
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• 2018

Cellular jamming phenomenon, defined as a kinetic arrest, is a commonly observed event in dense cell aggregates in epithelial tissues. Cells lose their motility when the density of the cell population becomes too high. Yet, not much is known about how the jamming occurs and how it influences individual cells in the population. In this study, we investigated the mechanisms during the formation of the jammed state by visualizing various dynamic components such as velocity, traction, and intercellular stress. The visualized properties exhibited interrelated features in similar time domains that can be categorized into specific stages, namely migrating, transitional and steady state. During the migrating stage, cells generated spatially correlated tractions and migrations at the collective migration step and lost these properties becoming a transitional stage. These stepwise analyses presented correlative components which are expected to adjust for explaining the detailed mechanisms of cellular jamming.

• Bulletin of the Korean Chemical Society
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• v.9 no.1
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• pp.48-52
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• 1988

New methods for the direct reduction of carboxylic acids to aldehydes through the treatments of B-acyloxy-9-borabicyclo[3.3.1]nonane (acyloxy-9-BBN) with tert-butyllithium and 9-borabicyclo[3.3.1]nonane or with lithium 9-boratabicyclo[3.3.1]nonane (Li 9-BBNH) are described. Both these systems provide the corresponding aldehydes from various carboxylic acids in high yields. A mechanism for the recuction through stepwise treatment of acyloxy-9-BBN with tert-butylithium and 9-BBN, which seems to involve the hydride migration through 9-BBN, is proposed and discussed in connection with the reduction through treatment of acyloxy-9-BBN with Li 9-BBNH.

• BMB Reports
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• v.51 no.5
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• pp.230-235
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• 2018

Bone resorption by multinucleated osteoclasts is a multistep process involving adhesion to the bone matrix, migration to resorption sites, and formation of sealing zones and ruffled borders. Macrophage colony-stimulating factor (M-CSF) and osteopontin (OPN) have been shown to be involved in the bone resorption process by respective activation of integrin ${\alpha}v{\beta}3$ via "inside-out" and "outside-in" signaling. In this study, we investigated the link between signal modulators known to M-CSF- and OPN-induced osteoclast adhesion and spreading. M-CSF- and OPN-induced osteoclast adhesion was achieved via activation of stepwise signals, including integrin ${\alpha}v{\beta}3$, $PLC{\gamma}$, $PKC{\delta}$, and Rac1. Osteoclast spreading induced by M-CSF and OPN was shown to be controlled via sequential activation, consistent with the osteoclast adhesion processes. In contrast to osteoclast adhesion, osteoclast spreading induced by M-CSF and OPN was blocked via activation of $PLC{\gamma}/PKC{\alpha}/RhoA$ signaling. The combined results indicate that osteoclast adhesion and spreading are selectively regulated via $PLC{\gamma}/PKC{\alpha}-PKC{\delta}/RhoA-Rac1$ signaling.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.479-492
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• 2020

Purpose: The purpose of this study is to analyze the impact of regional characteristics on population movement on the Seoul metropolitan areas. Method: To this end, 66 basic entities in the Seoul metropolitan area were divided into three regions by analyzing the demographic movement data from 2010 to 2016 and the factors for determining population movement within and between regions were identified by applying a stepwise regression technique. Result: The major analysis confirmed that the increase in the number of apartments in all areas of the Seoul metropolitan area, the increase in the number of single-family homes, the increase in the number of employees, the increase in manufacturers, the growth rate of knowledge, culture, and leisure industries, the increase rate of GRDP, and the opening of new subway stations. In particular, the growth rate of the number of apartments, the growth rate of the knowledge, culture and leisure industries, the increase rate of GRDP, and the opening of new subway stations played a positive role in increasing population inflow. Conclusion: The result showed that by region, the growth rate of knowledge, culture and leisure industries contributed greatly to the inflow of population in the first region, and that the opening of new subway stations and the increase of GRDPs were the main factors. The increase in the number of apartments and subway stations were the main factors in the three areas.

• Korean Journal of Social Welfare
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• v.62 no.3
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• pp.163-191
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• 2010

The purpose of this study is to explore the factors affecting the welfare needs of the rural marriage migrant females. A survey was conducted on 300 rural marriage migration females using probability sampling and for the analysis stepwise regression was used. The major findings of this study can be summarized as follows. The welfare needs of counselling on husband' behavior problem were higher in cases of worse mental health, better physical health, younger age and lower participation in the meetings with her fellow countrymen. The welfare needs on the children raising and education were relatively higher among the migrant females from Vietnam and younger age. The needs on the job skills training were lower in cases of the migrant females from Philippines, China(the Chinese) and were higher in cases of lower level of family understanding. The welfare needs on the job placement were higher among older and lower community affinity, and were lower in cases of the migrant females from Philippines. The results suggest that the welfare services should be differently provided to the migrant females in reflection of the age, education level, nationality and community resources. Further, the mental health screening test and treatment services for migrant females are needed since the welfare needs increase when the migration females have worse mental health condition.

• Journal of Digital Convergence
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• v.14 no.5
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• pp.185-195
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• 2016

The purpose of this study is to understand the nature of curation commerce in the environment of e-commerce in recent years rapidly changing and looking for ways to take advantage of it. Like the recent trend curation and subscription commerce has been in the limelight in a new way of e-commerce. However, not having appropriately adapted to the market, it has gone out of business or been changing the properties. In analyzing the specific characteristics of the migration queue commerce, it evaluated whether those characteristics do change through the mediating effect of the impact of satisfaction on purchase. This study was carried out using a structured questionnaire, by collecting the material for the 305 general public in the country and it was analyzed using stepwise regression method. After validating the hypothesis, 5 characteristics of curation commerce turned out to have a significant positive effect (+) on purchase and satisfaction of consumers using curation commerce to have a positive effect (+) on purchase. After organizing these findings and discussing the theoretical and practical implications, the direction for future research was proposed.

• Journal of Life Science
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• v.28 no.2
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• pp.265-273
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• 2018

Estrogen (E2) is involved in the development and progression of breast cancer and is mediated by estrogen receptor (ER). ER plays important roles in cellular proliferation, migration, invasion and causing drug resistance through diverse cross-talks with epidermal growth factor receptor (EGFR) and insulin-like growth factor-1 receptor (IGF-1R) signaling pathways in breast cancer cells. Breast cancer is caused mainly by break-down of homeostasis of endocrine signaling pathways especially by the uncontrolled expression and increased activities of E2/IGF-1/EGF, ER/G-protein estrogen receptor (GPER)/IGF-1R/EGFR and their intracellular signaling mediators. These changes influence the complex cross-talk between E2 and growth factors' signaling, eventually resulting in the progression of cancer and resistance against endocrine regulators. Thus, elucidation of the molecular mechanisms in stepwise of the cross-talk between E2 and growth factors will contribute to the customized treatment according to the diverse types of breast cancer. In particular, as strategies for the treatment of breast cancer with diverse genotypes and phenotypes, there can be use of aromatase inhibitors and blockers of E2 action for the ER+ hormone-dependent breast cancer cells and use of IGF-1R/EGFR activity blockers for suppression of cancer cell proliferation from the cross-talk between E2 and growth factors. Furthermore, changes in the expression of the ECM molecules regulated by the cross-talk between ER and EGFR/IGF-1R can be used for the targeted therapeutics against the migration of breast cancer cells. Therefore, it is required for the cross-talk among the signaling pathways of ER, GPER, IGF-1R and EGFR concerning cancer progression to be elucidated in more detail at the molecular level.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.4
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• pp.206-213
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• 2013

Glass eels (Anguilla japonica) are caught in the west coast of Korea on their migratory route from the breeding grounds in the Mariana Trench along the North Equatorial Current and the Kuroshio Current. To identify the food source of natural glass eels, we analyzed the stable C and N isotopes of glass eels caught in April 2012 and investigated possible food sources in the survey area. In particular, with respect to the stable C and N isotopes of particulate organic matter, we extended the surveying area to the northern parts of East China Sea as well as the west coast of Korea. The stable C and N isotope ratios of the glass eels caught in the west coast were found to be $-20.7{\pm}0.1$‰ and $5.0{\pm}0.2$‰, respectively. The stable C and N isotope ratios of the particulate organic matter in the west coast of Korea, in which the glass eels are assumed to eat the particulate organic matter as food source, were estimated to be $-24.0{\pm}0.3$‰ and $2.8{\pm}0.4$‰, respectively. Similar data were obtained from the northern part of the East China Sea, $-24.5{\pm}0.5$‰ and $0.8{\pm}0.3$‰. The stable isotope ratios showed values differing from the stepwise increasing rates up the food web in natural aquatic ecosystem, showing that particulate organic matter in the west coast of Korea and East China Sea was not served as the glass eels food source. This result suggested that the glass eels caught in the west coast might not assimilate nutrition from the marine environment during long migration.