• 대한치과교정학회지
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• 제28권6호
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• pp.915-926
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• 1998

Cytoskeleton은 세포핵과 세포외 기질을 연결하고 있어서 기질에 가해지는 물리적 힘에 의해 cytoskeletal change가 유도되고 이에 의해 세포의 개조활성이 영향을 받는다고 생각되어 왔다. 본 연구는 골모세포 활성에 대한cytoskeletal change의 역할을 규명하기 위한 것으로서, 신생 백서로부터 조골세포양 세포를 분리, 배양하고 네가지 농도의 cytochalasin B(CB) 또는 colchicine(COL)을 3시간 처리하였다. 다시 배양액을 교환하고 24시간 동안 배양하여 prostaglandin $E_2\;(PGE_2)$, interleukin-6(IL-6), tumor necrosis factor-$\alpha$(TNF-$\alpha$) 및 matrix metalloproteinase-1 (MMP-1) 생산을 측정하고 통계적으로 비교하였으며 cytoskeletal protein actin 변화를 관찰하기위하여 면역형광염색하고 형광현미경으로 관찰하여 다음과 같은 결과를 얻었다: 1. CB 처리군에서 $PGE_2$ 생산이 증가되는 경향을 보였고 COL 처리군에서는 약물농도에 비례하여 증가하였다. 2. IL-6 생산은 CB농도 1.0 ${\mu}g/ml$일때를 제외하고 증가되었다. 3. TNF-$\alpha$도 CB 농도가 1.0 ${\mu}g/ml$ 일때를 제외하고 증가하였다. 4. MMP-1 생산은 CB 처리군에서 감소하는 경향을 보이고 COL 처리군에서는 변화되지 않았다. 5. CB처리군에서는 cytoskeletal actin stress fibers가 사라지고 세포모양이 둥글어지는 경향을 보였다. 이상의 결과로 미루어 보아 cytoskeletal rearrangement는 골모세포유사세포의 활성, 특히 $PGE_2$, IL-6, 및 TNF-$\alpha$같은 paracrine/autocrine factor의 생산과 관련있는 것으로 보인다.

• IMMUNE NETWORK
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• 제3권2호
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• pp.136-144
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• 2003

Oral administration of antigen has long been considered as a promising alternative for the treatment of chronic autoimmune diseases including rheumatoid arthritis (RA), and oral application of type II collagen (CII) has been proven to improve pathogenic symptoms in RA patients without problematic side effects. To further current understandings about the immune suppression mechanisms mediated by orally administered antigens, we examined the changes in IgG subtypes, T-cell proliferative response, and proportion of interleukin (IL)-10 producing Th subsets in a time course study of collagen induced arthritis (CIA) animal models. We found that joint inflammation in CIA mouse peaked at 5 weeks after first immunization with CII, which was significantly subdued in mice pre-treated by repeated oral administration of CII. Orally tolerized mice also showed increase in their serum level of IgG1, while the level of IgG2a was decreased. T-cell proliferation upon CII stimulation was also suppressed in lymph nodes of mice given oral administration of CII compared to non-tolerized controls. When cultured in vitro in the presence of CII, T-cells isolated from orally tolerized mice presented higher proportion of $CD4^+IL-10^+$ subsets compared to non-tolerized controls. Interestingly, such increase in IL-10 producing cells were obvious first in Peyer's patch, then by 5 weeks after immunization, in mesenteric lymph node and spleen instead. This result indicates that a particular subset of T-cells with immune suppressive functions might have migrated from the original contact site with CII to inflamed joints via peripheral blood after 5 weeks post immunization.

• 중소기업연구
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• 제42권1호
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• pp.43-56
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• 2020

최근 미·중 기술 갈등이 심화되고 있다. 국가 보안을 이유로 시작된 미·중 갈등은 본원적으로는 중국 IT 제조 및 기술 기업들의 약진을 경계하는 미국 정부차원의 견제로 해석된다. 중국의 IT부문은 빠른 성장을 거듭하며 미국에 위협적인 존재가 되어 왔다. R&D지출, 특허, 논문 등 다양한 지표에서 중국은 빠른 성장을 지속해 왔고 특히 5G, AI (인공지능) 등 차세대 기술에 있어 중국은 미국에 큰 위협이 되고 있다. 그리고 그 중심에 화웨이가 있다. 2018년 화웨이는 세계 최대의 통신장비 제조사이자 미국의 혁신 기업인 애플을 제치고 세계 2위의 스마트폰 제조사가 되었고 최근에는 AI칩셋 제조, 빅데이터 분석, 클라우드 등에서 빠른 성장을 보이며 4차 산업혁명의 핵심 산업 전반에 있어 그 영향력을 강화하고 있는 미·중 갈등의 중심에 있는 기업이다. 본 연구는 화웨이 이슈를 중심으로 우리나라 중소기업에 대한 파급효과를 분석하는데 목적이 있다. 이를 위해 화웨이와의 국내 기업 거래 현황, 글로벌 밸류체인 관점에서의 화웨이의 협력관계, 우리나라의 화웨이 정보보안 이슈 및 정부의 정책적 대응이라는 세 가지 분석체계를 바탕으로 우리나라 제조 경쟁력 및 정보보안 역량 강화 등의 정책 제언을 제시하고자 한다.

• IMMUNE NETWORK
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• 제2권4호
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• pp.248-255
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• 2002

Background: TAP1 and TAP2 are two ABC transporter genes located within the class II region of the human MHC. Their protein products form a heterodimer whose function is to transport peptides from the cytoplasm into the endoplasmic reticulum. This study was performed to examine the polymorphism of TAP genes and the distribution of HLA-TAP haplotypes in the Korean population through family analysis. Methods: The subjects used in this study were 50 healthy Korean families consisting of 233 individuals. TAP1 (codons 333 and 637) and TAP2 (codons 379, 565, 577, 651, 665, and 687) typings were carried out by the PCR-restriction fragment length polymorphism (RFLP) method. HLA-DRB1 and DQB1 genotyping results from a previous study were used for HLA-TAP haplotype analysis. Results: The number (gene frequency) of TAP1 and TAP2 alleles detected were 3 for TAP1 (A 81.5%, B 17.0%, and C 1.5%) and 8 for TAP2 (A1 32.0%, A2 12.5%, B 34.0%, Bky2 6.5%, C 7.0%, D 3.0%, E 4.5%, and G 0.5%). Eleven TAP1-TAP2 haplotypes were observed with $frequency{\geq}1%$, among which 4 haplotypes (A-B, B-A1, A-Bky2, and C-E) showed weak but significant positive linkage disequilibrium (P<0.05). When DRB1-DQB1 haplotypes were extended to TAP1 and TAP2 loci, much diversification of haplotypes was observed: 19 different DRB1-DQB1 haplotypes formed 58 different haplotypes extended to TAP1 and TAP2 loci. These results add more evidence to the view that recombination hotspot is present within and around TAP gene region. Conclusion: The allele frequencies of TAP1 and TAP2 genes and the distribution of TAP1-TAP2 and HLA-TAP haplotypes were studied in Koreans based on a family study.

• 한국세라믹학회지
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• 제51권3호
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• pp.170-176
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• 2014

Effective glass frit compositions enabled to absorb laser energy, and to seal a commercial dye-sensitized solar-cell-panel substrate were developed by using $V_2O_5$-based glasses with various amounts of $TeO_2$ substitution. The latter was intended to increase the lifetime of the solar cells. Substitution of $V_2O_5$ by $TeO_2$ provided a strong network structure for the glasses via the formation of tetrahedral pyramids in the glass, and changed the various glass properties, such as glass transition temperature ($T_g$), dilatometric softening point ($T_d$), crystallization temperature, coefficient of thermal expansion (CTE), and glass flowage without any detrimental effect on the laser absorption property of the glasses. The thermal expansion mismatch (${\Delta}{\alpha}$) between the glass frit and the substrate could be controlled within less than ${\pm}5%$ by addition of 10 wt% of ${\beta}$-eucryptite. An 810 nm diode laser was used for the sealing test. The laser sealing test revealed that the VZBT20 glass frit with 10 wt% ${\beta}$-eucryptite was successfully sealed the substrates without interfacial cracks and pores. The optimum sealing conditions were provided by a beam size of 3 mm, laser power of 40 watt, scan speed of 300 mm/s, and 200 irradiation cycles.

• IMMUNE NETWORK
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• 제2권1호
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• pp.41-48
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• 2002

Background: Viral antigens presented on the cell surface in association with MHC class I molecules are recognized by CD8+ T cells. MHC restricted peptides are important in eliciting cellular immune responses. As peptide antigens have a weak immunigenicity, pH-sensitive liposomes were used for peptide delivery to induce effective cytotoxic T lymphocyte (CTL) responses. In the previous study, as the HBx peptides could induce specific CTLs in vitro, we tested whether the HLA-A2/$K^b$ transgenic mice that were immunized by HBx-derived peptides could be protected from a viral challenge. Methods: HBx-peptides encapsulated by pH-sensitive liposomes were prepared. $A2K^b$ transgenic mice were immunized i.m. on days one and seven with the indicated concentrations of liposome-encapsulated peptides. Three weeks later, mice were infected with $1{\times}10^7pfu$/head of recombinant vaccinia virus (rVV)-HBx via i.p. administration. The ovaries were extracted from the mice, and the presence of rVV-HBx in the ovaries was analyzed using human TK-143B cells. IFN-${\gamma}$ secretion by these cells was directly assessed using a peptide-pulsed target cell stimulation assay with either peptide-pulsed antigen presenting cells (APCs), concanavalin A ($2{\mu}g/ml$), or a vehicle. To generate peptide-specific CTLs, splenocytes obtained from the immunized mice were stimulated with $20{\mu}g/ml$ of each peptide and restimulated with peptide-pulsed APC four times. The cytotoxic activity of the CTLs was assessed by standard $^{51}Cr$-release assay and intracellular IFN-${\gamma}$ assay. Results: Immunization of these peptides as a mixture in pH-sensitive liposomes to transgenic mice induced a good protective effect from a viral challenge by inducing the peptide-specific CD8+ T cells. Mice immunized with $50{\mu}g/head$ were much better protected against viral challenge compared to those immunized with $5{\mu}g$/head, whereas the mice immunized with empty liposomes were not protected at all. After in vitro CTL culture by peptide stimulation, however, specific cytotoxicity was much higher in the CTLs from mice immunized with $5{\mu}g/head$ than $50{\mu}g/head$ group. Increase of the number of cells that intracellular IFN-${\gamma}$ secreting cell among CD8+ T cells showed similar result. Conclusion: Mice immunized with XEPs within pH-sensitive liposome were protected against viral challenge. The protective effect depended on the amount of antigen used during immunization. XEP-3-specific CTLs could be induced by peptide stimulation in vitro from splenocytes obtained from immunized mice. The cytotoxic effect of CTLs was measured by $^{51}Cr$-release assay and the percentage of accumulated intracellular IFN-${\gamma}$ secreting cells after in vitro restimulation was measured by flow cytometric analysis. The result of $^{51}Cr$-release cytotoxicity test was well correlated with that of the flow cytometric analysis. Viral protection was effective in immunized group of $50{\mu}g/head$, while in the in vitro restimulation, it showed more spectific response in $5{\mu}g$/head group.

• 디지털융복합연구
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• 제17권9호
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• pp.439-450
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• 2019

이 연구의 목적은 실행중심 무용교육의 패러다임에 관한 비판적 접근을 바탕으로 무용교육학의 학문적 정체성을 탐색하는 것이다. 한국의 무용교육은 1955년 교육부에서 고시된 제1차 교육과정 이후 학교무용으로서 65년의 역사를 지니고 있음에도 무용교육학으로서의 학문적 정체성이 견고하지 못하다. 전통적인 무용교육은 실행중심 패러다임에 따라 지나치게 교사중심, 실기기능중심, 연습중심으로 운영되었다. 그러나 최근 학교, 지역사회, 전문 분야에서 무용교육학은 새로운 패러다임 구축을 요구받고 있다. 이에 이 연구는 시계열 관점의 키워드 네트워크 분석을 실시하여 무용교육연구의 각 구간별 주요 내용을 검토하였다. 연구결과, 무용교육연구는 5개의 구간으로 구분되었다. 제1구간(1968~1979)은 체육학을 기반으로 한 무용교육의 실천, 제2구간(1980년~1989년)은 초등교육을 위한 창작 기반의 움직임 교육, 제3구간(1990년~1999년)은 교급별 무용교육과정의 체계화, 제4구간(2000년~2009년)은 문화예술교육 패러다임의 등장, 제5구간(2010년~2019년)은 교육실천과 학제의 다양화가 이루어졌다. 연구결과를 바탕으로 복합학으로서 무용교육학, 학제간 실천 및 연구를 지지할 수 있는 학문적 정체성을 정립할 수 있는 노력이 요청된다.

• 한국토양비료학회지
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• 제49권6호
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• pp.689-698
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• 2016

Specific metabolic network responses to mineral starvation are not well-defined. We examined a detailed broad-scale identification of metabolic responses of tomato leaf and root to N, P or K starvation. Tomato plants were grown hydroponically under optimal (5 mM N, 0.5 mM P, or 5 mM K) and starved (0.5 mM N, 0.05 mM P, or 0.5 mM K) conditions and metabolites were measured by LC-MS and GC-MS. Overall, the levels of metabolites (lipids, nucleotides, peptides and secondary metabolites) presented in this paper largely showed mineral- and tissue-specific responses. Most strikingly, G3P (glycerol-3-P), GPC (glycerol-P-choline) and choline phosphate responded differently to a type of mineral; an increase in N or K starvation and a decrease in P starvation. A dramatic increase in the levels of secondary metabolites, in particular, rutin and chlorogenate in both tomato tissues during N starvation were observed. Based on these data, it is necessary to clearly elucidate an unknown event taking place in a variety of abiotic impacts, and we are now studying to expand our knowledge on metabolic- and proteomic-responses using GS-MS and LC-MS.

• 한국도서관정보학회지
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• 제4권
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• pp.39-60
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• 1977

The purpose of this study is to build a model of inter-library cooperation's network in the information of library materials. Results of this study are 1. The YTational Assembly Library and the Central National I, ibrar:; should be unified. 2. The unified organization should be organized its cooperative quarter for itself (in the Central National Library). .And every library should he organized his quarter and personnel for the inter-library cooperation. 3. The cooperatior, organization in the re~ion should organized by the Regional Central Public Library. 4. In case of the Central National Library, financial problems required of the performance in the inter-library cooperation should he charged equally among the Central National Library, the library belong to the reader and the reader. In case of the regional Central Public Library, it should be charged equally arnozlg the regional Central Public Library, the library belon-g' to the reader and the reader. 5. The Regional Central Public Library in the seat of provincial government should be managed the cooperation's work of the individual library, and upward the unified Central Xarional Library should generalize. 6. The purchase of materials should be done by the character of the each library 1r:ith the assignment of the each subject should be decided in the meeting of the each library personne!. -2nd the budget for purchasing per the year should be decided on the minimum by the circumstances of the each library regionally. 7. The unified Regional Central Public Library in the seat of provincial government should be charged of the Union Catalog's expense regionally, and the Central National Library should be charged of that National Union Catalog's expense to cumulative the Fegional Union Catalog within a definite period of time. 8. Books without presentation of a specimen copy to the unified Central National Library should be purchased, and r.cr 'oe included to the National Union Catalog. 9. The cooperation of the each library should be decided on the law, and considered the character of the each region.

• 지식경영연구
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• 제15권3호
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• pp.37-66
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• 2014

Since social network service (SNS) has been widely used as a effective way for people to connect and communication with each other, the use of corporate SNS account also has increased. However, compared to a private SNS account, only few people have a continuous relationship with their corporate SNS account because the use of corporate SNS account tends to be one-time and temporary activity whenever the users just need events and information. Given the psychological side effects of using SNS, the relative lack of empirical studies on the impacts of emotional factor in SNS prevents the deeper understanding of the intention to continuous using corporate SNS account. Therefore, this study aims to explore key determinants of the intension to continuous using the corporate SNS account from a habit and emotional perspective. To bridge research gap, we attempt to divide emotional factor into the following 5 factors based on Mehrabian and Russell model (1974): intimacy, enjoyment (positive factor), privacy concern, anxiety (negative factor), arousal (arousal factor) and (dominant factor). The basic model is proposed to explore the effects of habit and emotional factors on the intension to continuous using the corporate SNS account. We then examine how the effects of habit and emotional factors differ depending on social media types (e.g., facebook and twitter). The results indicates that habit is related to emotional factors, and each emotional factor differently influences the intension to continuous using the corporate SNS account. The results also confirm that the effects of the habit and emotional factors on the intension to continuous using the corporate SNS account differ according to social media types. This study provides practical and useful guidance and the strategic marketing insight for managers in maintaining and improving the intension to continuous using the corporate SNS account.