• Journal of the Korean Chemical Society
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• v.23 no.1
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• pp.20-29
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• 1979

The origin of barriers to internal rotation of hydrogen peroxide and ethane is investigated by using the concept of Bonding and Antibonding Regions. The strong bond formations between the axial and end atoms on the same side make the real charge densities in these molecules less dependent on conformations than those in the hypothetical molecules having no axial atoms. Thus, the existence of the axial atoms should induce the migration of the transition density from the Bonding region to the Antibonding region. Barrier to internal rotation can be understood in terms of this migration of the transition density to such an extent that the change in nuclear-nuclear repulsion energy becomes the dominating part of the total perturbation energy.

• Radiation Oncology Journal
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• v.38 no.1
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• pp.18-25
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• 2020

Purpose: This study was aim to evaluate the patterns of failure according to radiotherapy (RT) target volume for cervical lymph nodes in metastases of unknown primary origin in head and neck region (HNMUO). Materials and Methods: Sixty-two patients with HNMUO between 1998 and 2016 were retrospectively reviewed. We analyzed the clinical outcomes and primary site failure depending on the radiation target volume. The target volume was classified according to whether the potential head and neck mucosal sites were included and whether the neck node was treated involved side only or bilaterally. Results: Potential mucosal site RT (mucosal RT) was done to 23 patients and 39 patients did not receive mucosal RT. Mucosal RT showed no significant effect on overall survival (OS) and locoregional recurrence (LRR). The location of primary site failure encountered during follow-up period was found to be unpredictable and 75% of patients with recurrence received successful salvage therapies. No significant differences in OS and LRR were found between patients treated to unilateral (n = 35) and bilateral neck irradiation (n = 21). Treatment of both necks resulted in significantly higher mucositis. Conclusions: We found no advantages in OS and LRR of patients with HNMUO when mucosal sites and bilateral neck node were included in the radiation target volume.

• Journal of the Korean Geographical Society
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• v.38 no.4
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• pp.505-517
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• 2003

The purpose of this paper is to examine the origin of materials of sanddune in the Chungcheongnamdo. The sands consist mainly of quartz with lesser amount of feldspar and other heavy minerals. With the exception of those from the granite, the sands have a very fine texture. Another characteristic of the sand grains is the low degrees of roundness and grading which indicates that the source areas of the material are not far from the accumulating field. The rivers and streams of this region are not effective in transporting sediments for the coastal dunes. It has been recognized that the beaches and sanddunes have recently been receded as a result of the decrease in materials and the devastating actions of the breakers. The degradation process occurs most actively when the spring tides attack the beaches and foredunes. There are strata with red tint along the coastal areas of the Chungcheongnamdo which trace their origin back to the Pleistocene. From the fact that they contain little or no gravels, the strata are believed to have been the sanddunes during the last interglacial period. This fossil dunes provide part of the materials for the development of the present-day sanddunes along the coastal areas of the region.

• Bulletin of the Korean Mathematical Society
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• v.60 no.4
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• pp.905-913
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• 2023

Suppose that M is a strictly convex hypersurface in the (n + 1)-dimensional Euclidean space 𝔼ⁿ⁺¹ with the origin o in its convex side and with the outward unit normal N. For a fixed point p ∈ M and a positive constant t, we put 𝚽_t the hyperplane parallel to the tangent hyperplane 𝚽 at p and passing through the point q = p - tN(p). We consider the region cut from M by the parallel hyperplane 𝚽_t, and denote by I_p(t) the (n + 1)-dimensional volume of the convex hull of the region and the origin o. Then Schneider's characterization theorem for ellipsoids states that among centrally symmetric, strictly convex and closed surfaces in the 3-dimensional Euclidean space 𝔼³, the ellipsoids are the only ones satisfying I_p(t) = 𝜙(p)t, where 𝜙 is a function defined on M. Recently, the characterization theorem was extended to centrally symmetric, strictly convex and closed hypersurfaces in 𝔼ⁿ⁺¹ satisfying for a constant 𝛽, I_p(t) = 𝜙(p)t^𝛽. In this paper, we study the volume I_p(t) of a strictly convex and complete hypersurface in 𝔼ⁿ⁺¹ with the origin o in its convex side. As a result, first of all we extend the characterization theorem to strictly convex and closed (not necessarily centrally symmetric) hypersurfaces in 𝔼ⁿ⁺¹ satisfying I_p(t) = 𝜙(p)t^𝛽. After that we generalize the characterization theorem to strictly convex and complete (not necessarily closed) hypersurfaces in 𝔼ⁿ⁺¹ satisfying I_p(t) = 𝜙(p)t^𝛽.

• Journal of The Korean Astronomical Society
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• v.51 no.4
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• pp.89-110
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• 2018

Active Galactic Nucleus (AGN) variability can be used to study the physics of the region in the vicinity of the central black hole. In this paper, we investigated intra-night optical variability of AGN in the COSMOS field in order to understand the AGN instability at the smallest scale. Observations were performed using the KMTNet on three separate nights for 2.5 to 5 hours at a cadence of 20 to 30 min. We find that the observation enables the detection of short-term variability as small as ~ 0.02 and 0.1 mag for R ~ 18 and 20 mag sources, respectively. Using four selection methods (X-rays, mid-infrared, radio, and matching with SDSS quasars), 394 AGN are detected in the $4deg^2$ field of view. After differential photometry and ${\chi}^2$-test, we classify intra-night variable AGN. The fraction of variable AGN (0-8%) is statistically consistent with a null result. Eight out of 394 AGN are found to be intra-night variable in two filters or two nights with a variability level of 0.1 mag, suggesting that they are strong candidates for intra-night variable AGN. Still they represent a small population (2%). There is no sub-category of AGN that shows a statistically significant intra-night variability.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.47.2-47.2
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• 2015

At local, galaxy properties are well known to be clearly different in different environments. However, it is still an open question how this environment-dependent trend has been shaped. In this presentation, we will show the results of our investigation about the evolution of star-formation properties of galaxies over a wide redshift range, from z~2 to z~0.5, focusing its dependence on their stellar mass and environment. In the UKIDSS/UDS region, we estimated photometric redshifts and stellar population properties, such as stellar masses and star-formation rates, using the deep optical and near-infrared data available in this field. Then, we identified galaxy cluster candidates at z~0.5-2. Through the analysis and comparison of star-formation (SF) properties of galaxies in clusters and in field, we found interesting results regarding the evolution of SF properties of galaxies: (1) regardless of redshifts, stellar mass is a key parameter controlling quenching of star formation in galaxies; (2) At z<1, environmental effects become important at quenching star formation regardless of stellar mass of galaxies; and (3) However, the result of the environmental quenching is prominent only for low mass galaxies (M* < $10^{10}M_{\odot}$) since the star formation in most of high mass galaxies are already quenched at z > 1.

• Asia Marketing Journal
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• v.11 no.2
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• pp.97-119
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• 2009

The growth of international trade and the formation of supranational economic and political trading blocks have noticeably widened the presence on the market of products of different national origins. This has stimulated interest in explaining the Country-of-Origin (COO) role in domestic and international markets and its consequences on consumer behaviour. Since the consumer purchasing decisions can be decisive to the success of a company's strategy in domestic and foreign markets, the objective of this study is to present empirical evidence on the extent to which reputation of firms associated to a certain COO are related to consumer purchase intention. Additionally our study considers ethnocentrism as a variable that partially explains the rejection of imports products based on its foreign origin. The empirical application of the proposed model is related to the purchase of Korean automobiles which represents 5.7% of the national market share in Spain. Structural equation modelling was used to analyse the data collected from 202 personal interviews carried out in a large Spanish region. The results show that reputation of firms associated to a certain COO in an important factor to establish business relationships involving consumers and firms from different countries and increase intentions to purchase Korean products. Additionally, ethnocentric consumers prefer to purchase domestic products rather than foreign imports as an attempt to protect national economy however the negative effect of ethnocentrism is weaker than positive effect of firms reputation of a COO.

• Anatomy and Cell Biology
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• v.57 no.3
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• pp.346-352
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• 2024

Studies reveal variations in the in the origin, number, and branching patterns of the lateral circumflex femoral artery (LCFA). The present study aimed to document such variations and their potential clinical applicability. Thirty-two femoral triangles of 16 embalmed adult human cadavers were dissected to investigate the variation in the origin, number, and branching patterns of LCFA. The main branches of the LCFA were tracked independently for numerical variations in branching pattern. The distance between the origin of LCFA and mid inguinal point (MIP) was also measured in each case. LCFA was most commonly arising from profunda femoris (PF), followed by femoral artery (FA) and common trunk of the femoral artery (CFA). Duplication LCFA was observed in 15 (46.87%) limbs, in 5 (31.25%) cases duplication was only on right side, in 4 (25%) cases duplication was only on left side and in 3 (18.75%), duplication was bilateral. Cases with duplication of LCFA, showed numerical variations with descending pattern being the most common. The average distance of LCFA1 and LCFA2 from mid-inguinal point was 5.77±1.35 cm and 6.14±2.05 cm respectively. Detailed information regarding the occurrence of duplication will be great importance for surgeons, interventional radiologists, and other medical professionals performing procedures in the femoral region. Knowledge of variation of branching pattern of LCFA is utmost important as surgeons use the descending branch of the LCFA in bypass grafting and vascular reconstruction surgeries.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1234-1240
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• 2015

Heat shock RNA 1 (HSR1) is described as a "eukaryotic heat-sensing noncoding RNA" that regulates heat shock response in human and other eukaryotic cells. Highly conserved HSR1 sequences have been identified from humans, hamsters, Drosophila, Caenorhabditis elegans, and Arabidopsis. In a previous study, however, it was suggested that HSR1 had originated from a bacterial genome. HSR1 showed no detectible nucleotide sequence similarity to any eukaryotic sequences but harbored a protein coding region that showed amino-acid sequence similarity to bacterial voltage-gated chloride channel proteins. The bacterial origin of HSR1 was not convincible because the nucleotide sequence similarity was marginal. In this study, we have found that a genomic contig sequence of Comamonas testosteroni strain JL14 contained a sequence virtually identical to that of HSR1, decisively confirming the bacterial origin of HSR1. Thus, HSR1 is an exogenous RNA, which can ectopically trigger heat shock response in eukaryotes. Therefore, it is no longer appropriate to cite HSR1 as a "eukaryotic functional noncoding RNA."

• Proceedings of the Korea Technology Innovation Society Conference
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• 2006.11b
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• pp.155-166
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• 2006

Application of industry roadmap is to propose the vision on the future through correction and supplement of various environment change(nation competition power uplift, origin technology development, long and short-term vision establishment, R&D investment improvement, co-work increase etc). Now, in Jeju region, Roles of traditional medicine is needed by environmental needs(competition loss of Jeju industry, limitation of tourism industry etc). Thus, the purpose of this study is to contribute to region economy activity by building the TRM of foods field in traditional oriental medicine industry through the analysis of earlier TRM paper and materials.