• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1353-1358
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• 2008

Benzyl arylether dendrimers with zinc porphyrin core and terminal vinyl groups have been synthesized and their photophysical properties and the influence of dendritic environments were investigated. Free base porphyrin-cored benzyl arylether dendrimers 1a-1c and 3a-3c, and their zinc derivatives 2a-2c and 4a-4c have been prepared. Absorption spectra are similar for all porphyrin-cored benzyl arylether dendrimers, except that absorption intensity at 280 nm increases in the higher generation of dendrimer. Fluorescence spectra are similar with two bands for all free base porphyrin dendrimers 1a-1c and 3a-3c, although fluorescence intensity ratio of shorter wavelength emission band to longer wavelength band varies with the generation of dendrimer. Emission efficiencies of 1a-1c and 3a-3c are lower than that of TTP. Emission efficiencies of 2a-2c and 4a-4c are higher than that of ZnTTP. Absorption and emission properties of 1a-1c, 2a-2c, 3a-3c, and 4a-4c were affected negligibly with dendritic environments.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.4
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• pp.233-238
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• 2023

Schwannomas exhibit histopathological variation that leads to diagnostic dilemmas, although less frequent in the oral cavity. We describe a case with unique histopathology and no relevant clinical history that adds to the breadth of literature on the diversity presented by Schwannoma. A 60-year-old female patient presented with a small dome-shaped, asymptomatic swelling on the alveolar ridge 6 years in duration. Histopathologically, it showed rich cellular pathology with a unique arrangement of tumor cells forming irregular rosettes. Each rosette presented with a central core of fibrin-collagenous material and the tumor cells were arranged on the periphery, exhibiting epithelioid change with evidence of mild cellular and nuclear pleomorphism. On immunohistochemical evaluation, the cells were strongly and diffusely positive for S-100 and negative for Ki-67. A diagnosis of benign Schwannoma with a rosette-like arrangement with epithelioid change was made. The case report emphasizes the risk of misdiagnosis and the importance of awareness regarding rare histopathological variants of Schwannoma.

• Korea journal of population studies
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• v.19 no.2
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• pp.139-173
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• 1996

This study is an attempt to identify factors affecting korean immigrants concentration in small business enterprises in the middleman minority sector including the priphery and core sectors, with the private wage and self-employed worker examined in each sector, employing the 5 percent public use sample from the 1980 United States census. One out of five koreans aged 25∼64 years is engaged in self-employed small businesses, while the majority of koreans (4 out of 5) are in the private wage sector. In contrast to expectations, English language difficulties and inferior education are not the prime factors affecting self-employment small businesses. The korean self-employed small business owners both in the periphery sector and in the core sector showed the 'middle' strata of their position in the social structure in terms of their industry, occupation, earnings, etc.

• Journal of the Korean Professional Engineers Association
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• v.16 no.1
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• pp.20-34
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• 1983

A phenomenon in the unplanned urban sprawl of Cheong-ju city has to be rest-rained from disposing and to develop, though progress in urbanization inevitably decreases rural area. So, this thesis aims at reviewing, revising and guiding toward the more effective land use planning practice and zoning mechanism and system of Cheong-ju city. I proposed that land use planning should be had several factors and thereupon that Korean zoning mechanism and system including Building Code should be amended because of inducing human activities in buildings and facilities not to demarcate and plan every one of them. First, the factors of urban planning are a rather diversified approach to it than a unified, supplementation of the applicable difference in time between preparing and appling it, a solid controlling system, a micro and macro planning theory and giving serious consideration for the inertia from the existing land use. Second, the applicable amendments for our zoning mechanism including Eluding Code are as follows; a need of reorganization for Zoning Ordinance appricated to different regulation concerning a scale and peculiarity of a oily, a decision of the different earmarked confinement in area to different zone ana from Zoning Ordinance in City Planning Law, a demarcated facilities and the more detailed land use concerning human activies than the exsisting and entrusting decision on the ways and processes of it to every rural city planning committee, a settlement of zone ana area considering for block-unit and Planned Unit Development(P. U. D.), and a need of security jurisprudence in order to solve the zoning regulation rather in City Planning Law than in Building Code that our zoning regulation and controlling system are depended on. According to these applicable amendments to Cheong-ju city, I proposed the conceptions of Cheong-ju city land use planning are as follows; a reinforcement with one cored pattern of urban land use, a selection of gradual urban sprawl by way of city development and renewal, a strengthening accessibility to the core of the city with Plurizing the system of arterial roads, a choice of priority to conservation at the core of tile city and security of open spaces and parking area at the area of the city, a harmonization between development and conservation at the inner ring area that is situated between the core and periphery reserved area in order to develop in the future, a buffered open space situated at the congested area with heterogenous functions, and a completion of urban open space system. The proposal made here so far is for the hope of the better structure of Cheong-ju city that should be granted to the peculiarity developed with educational, cultural, conservative and self-sufficient city functions.

• Korean Journal Plant Pathology
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• v.2 no.1
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• pp.1-11
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• 1986

Negatively stained dip preparations from Euonymus showing vein clear symptoms revealed bacilliform particles. The particles tentatively referred to as the Euonymus vein clear virus(EVCV) have a relatively complex structure, measuring 230-280nm in length and 70-80nm in diameter. They have an envelope, 8-10nm thick, provided with evenly spaced beadlike projection about 5-6nm long. The inner tubular core which had no envelope showed helical structures, 200-220nm long, and 50-55nm in diameter. This inner tubular core is interpreted as the virus nucleocapsid. A striking association of virus particles with the nuclei of infected cells was apparent from sections which showed numberous virus particles at the nuclear periphery and in what appeared to be intranuclear virus particle inclusions. Careful examination of these apparent inclusions revealed the presence of the nuclear envelope surrounding them, in addition to cytoplasmic organelles within them. Such profiles were interpreted as having arisen when the sections passed through invaginations of the cytoplasm into the nucleus. In all the sections showing virus particles associated with the nucleus, large number of virus particles were found to be present in expanded areas between the two lamellae of the nuclear envelope. This location is suggested as a possible site of virus assembly. Serveal micrographs of particles found in this location suggested incorporation of the inner lamella of the nuclear envelope into the viral envelope. Various micrographs indicated a possible helical arrangement of certain components present in the virus core.

• Korean Journal of Radiology
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• v.23 no.4
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• pp.446-454
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• 2022

Objective: To evaluate whether hyperoxia-induced ΔR₁ (hyperO₂ΔR₁) can accurately identify histological infarction in an acute cerebral stroke model. Materials and Methods: In 18 rats, MRI parameters, including hyperO₂ΔR₁, apparent diffusion coefficient (ADC), cerebral blood flow and volume, and ¹⁸F-fluorodeoxyglucose uptake on PET were measured 2.5, 4.5, and 6.5 hours after a 60-minutes occlusion of the right middle cerebral artery. Histological examination of the brain was performed immediately following the imaging studies. MRI and PET images were co-registered with digitized histological images. The ipsilateral hemisphere was divided into histological infarct (histological cell death), non-infarct ischemic (no cell death but ADC decrease), and nonischemic (no cell death or ADC decrease) areas for comparisons of imaging parameters. The levels of hyperO₂ΔR₁ and ADC were measured voxel-wise from the infarct core to the non-ischemic region. The correlation between areas of hyperO₂ΔR₁-derived infarction and histological cell death was evaluated. Results: HyperO₂ΔR₁ increased only in the infarct area (p ≤ 0.046) compared to the other areas. ADC decreased stepwise from non-ischemic to infarct areas (p = 0.002 at all time points). The other parameters did not show consistent differences among the three areas across the three time points. HyperO₂ΔR₁ sharply declined from the core to the border of the infarct areas, whereas there was no change within the non-infarct areas. A hyperO₂ΔR₁ value of 0.04 s^-1 was considered the criterion to identify histological infarction. ADC increased gradually from the infarct core to the periphery, without a pronounced difference at the border between the infarct and non-infarct areas. Areas of hyperO₂ΔR₁ higher than 0.04 s^-1 on MRI were strongly positively correlated with histological cell death (r = 0.862; p < 0.001). Conclusion: HyperO₂ΔR₁ may be used as an accurate and early (2.5 hours after onset) indicator of histological infarction in acute stroke.

• Journal of the Economic Geographical Society of Korea
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• v.9 no.2
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• pp.243-260
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• 2006

The continuing enlargement, deepening integration of EU and penetration of extra-EU enterprise into EU market are forming a new geographical restructure of the production system. In this paper, I analyse the changing geography of the EU automotive production system. The globalization and regionalisation of production activity intensify a competition among the enterprise. The European automotive production system changes to a platform system and a modular system for a diminution of productive costs, a development of various products and a frequent innovation of products. The European automotive enterprise is restructuring geographically the production functions and products in order to promote efficiency on a new production system, enlarged production space and intensified economic integration. The European automotive industry tends to a spatial specialization and agglomeration according to the locational factors of production functions and products and the locational condition of regions. This intensifies the geographical hierarchic structure of production activity between the core and the periphery.

• Journal of Information Management
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• v.36 no.4
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• pp.199-215
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• 2005

Experts participating in the knowledge expert network externalize their implicit knowledge by providing information or writing reports. Almost all the members of the network share externalized knowledge and the network facilitate the dissemination and diffusion of knowledge. Individuals reproduce another implicit knowledge by internalizing shared knowledge through the network and re-created knowledge is externalized, establishing knowledge circulation. In this paper, we analyze the expert groups of the Global Network of Korean Scientists & Engineers(KOSEN, www.kosen21.org), the Korea's No. 1 science and engineering knowledge expert community, with the application of the theory of policy network proposed by Marsh & Rhodes. According to the principal standards of policy network classification such as the number of participants, interaction among participants, consistency, distribution of resources and dependency, we categorize the KOSEN expert groups as closed policy network and opened issue network, and divide closed policy network into core community and periphery community.

• Parasites, Hosts and Diseases
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• v.31 no.3
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• pp.183-192
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• 1993

A transmission electron microscopic study was performed to observe the ultrastructures of the male germinal cells and spermatozoa of Fibricola seoulensis. Spermatogonia were found in the periphery of the testis and characterized by large nuclei and comparatively little cytoplasms. Spermatocytes contained an oval to spherical nucleus. Their nuclear volume was little larger in comparative to that of cytoplasm, and the chromatin was comparatively little. The early spermatids were characterized by a great amount of cytoplasm, and numerous mitochondria encircled the nucleus. In a more advanced spermatids the electron-dense strands of chromatin appeared in the nucleus, and a pair of rootlet of the axoneme and a microtubule-organizing center (MTOC) were observed near the nucleus. The sectioned spermatozoa were found in the testis and the seminal vesicle. Their cross sectional views were divided into 6 types when they were distinguished on the basis of the morphology and components. The spermatozoa of F. seoulensis showed two flagella of 9+1 type axoneme.

• The Journal of the Korea Contents Association
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• v.14 no.5
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• pp.322-331
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• 2014

The objective of this study is to examine the effect of regional globalization and its impact to globalized company. As emerging markets evolve from the periphery to the core of marketing practice, we will need to figure out their unique characteristics. Emerging markets are distinctly different from mature markets. Because of market heterogeneity it is important to segment customer and find out their characteristics for the companies. In this research we explores how inward internationalization, susceptibility to global consumer culture affect consumer's brand attitude and adoption of global brand. This study examines various strategic issues in the context of China. The result suggest that inward internationalization is an antecedent factor of susceptibility to global consumer culture and also influence to brand attitude and brand adoption positively. Several implications for Korean content providing companies and marketing strategies are discussed.