• Title/Summary/Keyword: Ki-ho School

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Overexpression of Periostin Protein in Non-Small Cell Lung Carcinoma is Not Related with Clinical Prognostic Significance

  • Park, Won-Young;Shin, Dong-Hoon;Kim, Jae-Ho;Lee, Min-Ki;Lee, Ho-Seok;Lee, Chang-Hun
    • Tuberculosis and Respiratory Diseases
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    • v.72 no.2
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    • pp.132-139
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    • 2012
  • Background: Periostin is preferentially expressed in periosteum, indicating a potential role in bone formation. Recently, there have been emerging controversies about its role in invasion and metastasis of human malignancies. We attempted to determine the clinicopathological significance of periostin expression in non-small cell lung carcinoma (NSCLC). Methods: Immunohistochemical staining of periostin protein from 91 cases of NSCLCs was performed using tissue microarray blocks. The results were correlated with clinicopathological parameters. Results: Positive reaction to periostin was predominantly noted in the tumor stroma. The strongest reaction presented as a band-like pattern just around the tumor nests. Non-neoplastic lung tissue and most in-situ carcinomas did not show a positive reaction in their stroma. With respect to tumor differentiation, moderate to poor differentiated tumors (47/77) revealed even higher periostin expression than the well-differentiated ones (4/14) (p=0.024). High periostin expression was positively correlated with E-cadherin and p53 expression, but was not related with patient age, sex, tumor type, PCNA index, b-catenin, cyclin D1, pTNM-T, pTNM-N, stage, and patient survival (p>0.05). Conclusion: These results suggest that periostin might play a role during the biological progression of NSCLC, but may not be related to the clinical prognostic parameters.

Epidemiological Characteristics of Mobile Phone Ownership and Use in Korean Children and Adolescents

  • Byun, Yoon-Hwan;Ha, Mina;Kwon, Ho-Jang;Choi, Kyung-Hwa;Burm, Eunae;Choi, Yeyong;Lim, Myung-Ho;Yoo, Seung-Jin;Paik, Ki-Chung;Choi, Hyung-Do;Kim, Nam
    • Environmental Analysis Health and Toxicology
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    • v.28
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    • pp.18.1-18.8
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    • 2013
  • Objectives As public concern on possible harmful effects of mobile phone in children has been raised, information of epidemiological characteristics of mobile phone use in children and adolescents will be essential for public health policy. Methods Using three databases (n=21,693) collected from 2008 to 2011, we examined characteristics of mobile phone ownership and use, and socioeconomic positions (SEP) in Korean children and adolescents. Results The ownership rate and the amount of mobile phone use were higher in females than males, in higher school grades than lower grades, and at 2011 than 2008. The average age of first mobile phone ownership was shown to decrease from 12.5 years in currently high school students to 8.4 years in currently elementary school students at 2011. More than 90% of children in the 5th grade owned a mobile phone. More children owned a mobile phone in lower SEP communities than in higher SEP. Children with parents educated less than those with parents educated more were more likely to own and use mobile phone. Conclusions Considering the epidemiological characteristics of mobile phone use, precautionary measures to prevent unnecessary exposure to mobile phones are needed in children and adolescents.

Fabrication of Porous β-TCP Bone Graft Substitutes Using PMMA Powder and their Biocompatibility Study (PMMA를 이용한 다공질 β-TCP 골충진제 제조 및 생체적합성 평가)

  • Song, Ho-Yeon;Youn, Min-Ho;Kim, Young-Hee;Min, Young-Ki;Yang, Hun-Mo;Lee, Byong-Taek
    • Korean Journal of Materials Research
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    • v.17 no.6
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    • pp.318-322
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    • 2007
  • Porous ${\beta}-tricalcium$ phosphate $({\beta}-TCP)$ bioceramic was fabricated by pressureless sintering using commercial HAp and different volume percentages of PMMA powders (30-60 vol.%). The range of spherical pore size was about $200-250\;{\mu}m$ in diameter. By increasing the PMMA content, the number of pores and their morphology were dramatically changed as well as decreased the material properties. In case of using 60 vol.% PMMA content, network-type pores were found, due to the necking of the PMMA powders. The values of relative density, elastic modulus, bending strength and hardness of the 60 vol.% PMMA content sample, sintered at $1500^{\circ}C$, were about 46%, 22.2 GPa, 5MPa and 182 Hv respectively. Human osteoblast-like MG-63 cells and osteoclast-like Raw 264.7 cells were well grown and fully covered all of the porous ${\beta}-TCP$ bodies sintered at $1500^{\circ}C$.

Expressional Profiling of Connexin Isoforms in the Initial Segment of the Male Reproductive Tract during Postnatal Development

  • Seo, Hee-Jung;Seon, Chan-Wook;Choi, In-Ho;Cheon, Yong-Pil;Cheon, Tae-Hoon;Lee, Ki-Ho
    • Reproductive and Developmental Biology
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    • v.34 no.2
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    • pp.103-109
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    • 2010
  • Functional regulation of a specific tissue or organ is controlled by a number of ways, including local cell-cell interaction. Of several forms of cell-cell junctional complexes, gap junctions are caught a great attention due to a formation of direct linkage between neighboring cells. Gap junctions are consisted of connexin (Cx) isoforms. In the present study, we evaluated expressional profiling of Cx isoforms in the rat initial segment (IS) of the male reproductive tract at different postnatal ages. The presence and expression of 13 Cx isoform mRNAs were determined by semi-quantitative real-time PCR analyses. A total of 8 Cx isoform mRNAs were detected in the IS of the male rats during postnatal development. The highest level of Cx30.3 mRNA was found at 5 months of age, while abundance of Cx31 mRNA was the highest at 1 year of age. Expression of Cx31.1 gene was relatively consistent during the postnatal development. Fluctuation of Cx32 and 37 gene expression was observed during the postnatal period. Significant elevation of Cx40 mRNA abundance was detected at 25 days of age and older ages. Expression patterns of Cx43 and 45 genes were similar with the highest level at 2 weeks of age, followed by gradual decreases at older ages. These results indicate differential regulation on expression of Cx isoforms in the rat IS during postnatal development. A complicated regulation of gene expression of Cx isoforms in the IS at different postnatal ages is suggested.

An Analysis and Survey on the Experimental and Practical Science Education of Middle School in Korea (현행 중등학교 과학 실험.실습 교육 실태 조사 및 그 운영 진단(I)-중학교 과학 실험.실습 교육을 중심으로-)

  • Lee, Yoon-Jong;Ki, U-Hang;Kim, Young-Ho;Chung, Won-Woo;Yang, Seong-Young;Kang, Yong-Hee;Ahn, Byung-Ho;Lim, Seong-Kyu;Yoon, Ill-Hee;Kim, Joong-Wook;Yun, Sung-Hyo
    • Journal of The Korean Association For Science Education
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    • v.17 no.4
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    • pp.435-450
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    • 1997
  • The status of facilities, management for the experiment, practices, teaching methods in middle schools have been investigated. The present status and reasonable management of the middle school science education have been grasped from the questionaires. To do this 125 secondary science teachers, 1,745 students and 70 principals of schools in Korea are administered questionaires of Science Education Reserch Institute of Kyungpook National University(1996). The results of this study are as follows : The reasonable management for experiments and practices of science education were scanty in the middle school around the urban and rural school owing to the shortage of facilities and equipments, crowded class, excessive class works for teacher, excessive contents of present textbooks and insufficiency of the administrative supports etc. The current teaching method of middle school science has emphasized knowledge. This fact does not satisfy the objective of learning due to lack of the teaching method. Desirable directions for the improvement of present status of middle school science education were proposed in this paper

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CO/HO-1 Induces NQO-1 Expression via Nrf2 Activation

  • Kim, Hyo-Jeong;Zheng, Min;Kim, Seul-Ki;Cho, Jung-Jee;Shin, Chang-Ho;Joe, Yeon-Soo;Chung, Hun-Taeg
    • IMMUNE NETWORK
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    • v.11 no.6
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    • pp.376-382
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    • 2011
  • Background: Carbon monoxide (CO) is a cytoprotective and homeostatic molecule with important signaling capabilities in physiological and pathophysiological situations. CO protects cells/tissues from damage by free radicals or oxidative stress. NAD(P)H:quinone oxidoreductase (NQO1) is a highly inducible enzyme that is regulated by the Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway, which is central to efficient detoxification of reactive metabolites and reactive oxygen species (ROS). Methods: We generated NQO1 promoter construct. HepG2 cells were treated with CO Releasing Molecules-2 (CORM-2) or CO gas and the gene expressions were measured by RT-PCR, immunoblot, and luciferase assays. Results: CO induced expression of NQO1 in human hepatocarcinoma cell lines by activation of Nrf2. Exposure of HepG2 cells to CO resulted in significant induction of NQO1 in dose- and time-dependent manners. Analysis of the NQO1 promoter indicated that an antioxidant responsible element (ARE)-containing region was critical for the CO-induced Nrf2-dependent increase of NQO1 gene expression in HepG2 cells. Conclusion: Our results suggest that CO-induced Nrf2 increases the expression of NQO1 which is well known to detoxify reactive metabolites and ROS.

Nanotribological Properties of Chemically Modified Graphene

  • Kwon, Sangku;Ko, Jae-Hyeon;Byun, Ik-Su;Choi, Jin Sik;Park, Bae Ho;Kim, Yong-Hyun;Park, Jeong Young
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.159-159
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    • 2013
  • Atomically thin graphene is the ideal model system for studying nanoscale friction due to its intrinsic two-dimensional anisotropy. Furthermore, modulating its tribological properties could be an important milestone for graphene-based micro and nano-mechanical devices. Here, we report that the tribological properties can be easily altered via simple chemical modifications of the graphene surface. Friction force microscopy measurements show that hydrogenated, fluorinated, and oxidized graphenes exhibit, 2-, 6-, and 7-fold enhanced nanoscale friction on their surfaces, respectively, compared to pristine graphene. The measured nanoscale friction should be associated with the adhesive and elastic properties of the chemically modified graphenes. Density functional theory calculations suggest that, while the adhesive properties of chemically modified graphenes are marginally reduced down to ~30%, the out-of-plane elastic properties are drastically increased up to 800%. Based on these findings, we propose that nanoscale friction on graphene surfaces is characteristically different from that on conventional solid surfaces; stiffer graphene exhibits higher friction, whereas a stiffer three-dimensional solid generally exhibits lower friction. The unusual friction mechanics of graphene is attributed to the intrinsic mechanical anisotropy of graphene, which is inherently stiff in plane, but remarkably flexible out of plane. The out-of-plane flexibility can be modulated up to an order of magnitude by chemical treatmentof the graphene surface. The correlation between the measured nanoscale friction and the calculated out-of-plane flexibility suggests that the frictional energy in graphene is mainly dissipated through the out-of-plane vibrations, or the flexural phonons of graphene.

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Study on the Improvement of Strength of Excavator Attachments Considering the Field Environment (굴삭기 작업장치의 설계 하중을 고려한 강도 개선에 대한 연구)

  • Nam, Kwang-Sik;Choi, Jin-Kyu;Choi, Ho-Min;Kim, Jae-Ki;Yeum, Sang-Hun;Lee, Seok-Soon
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.1
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    • pp.122-128
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    • 2016
  • The purpose of this study was to develop improved strength of an arm and a boom on over-load environment, which causes damage in the initial design statement. To develop improved strength of an excavator front group, we calculated load conditions using the MATLAB program, and using these conditions, we performed a structural analysis of an excavator front group for the maximum digging force condition. Finally we performed a topology optimization to reduce weights of an arm and a boom, and we re-modeled an arm and a boom based on the topology design results and re-performed the structural analysis. The strength of the re-design is higher than the initial design but its weight is almost the same as the initial design.

Bibliographic Studies of Depilation (탈모(脫毛)에 대(對)한 문헌적(文獻的) 고찰(考察))

  • Jang, Hae-Young;Choi, Kwan-Ho;Kim, Sung-Hyun;Kwon, Ki-Rok;Kim, Byung-Woo
    • Journal of Pharmacopuncture
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    • v.5 no.2
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    • pp.92-108
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    • 2002
  • According to the bibliographic studies of Depilation, the following conditions were made after literary studies.; 1. According to the period, The depilation have been named variously, for example, Balta(髮墮), Balgu(髮去), Balrak(髮落), Mobal(毛拔), Yupung(油風), Dokchang(禿瘡), Guijidu(鬼?頭), Dokban(禿班), etc. 2. The cause of depilation was deficiency of kidney(腎虛), defciency of Qi of the lung(肺氣虛), excessive heat of blood system(血熱), deficiency of Qi and blood system(氣血虛), deficiency of blood system(血虛), and endogenouse cause of, etc. 3. The depilation is meaning fallen hair in head. There are multiform type in the symptoms of depilation; round shape, ellipse type & bald head. 4. The herbal treatment was used Yukmijihwaghwan(六味地黃丸), Palmihwan(八味丸), Singihwan(腎氣丸), Hwangigunjungtang(黃耆建中湯), Samultang(四物湯), ect. and external herbal reatment was Sineungyangjindan(神應養鎭丹), Bangpungtongsungsan(防風通聖散), ect.

Development of an e-SCM system for a supply chain of an auto mobile company (자동차부품 조달 공급망을 위한 e-SCM 시스템 구현)

  • Lee, Jun-Su;Kim, Ki-Seong;Rhu, Jae-Byung;Oh, Myung-Hyun;You, Tae-Woo;Jeong, Byung-Ho
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2005.05a
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    • pp.72-79
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    • 2005
  • This paper deals with the construct of e-SCM System for a supply chain of an auto-mobile company. Two first vendors and two second vendors of a bus company are included in the objects of developing e-SCM system. We analyzed the information flow and business process within vendor and between vendors by using data flow diagram, to describe process to-be model of the e-SCM system. And to analyze and design the process of the system, we used Unified Modeling Language.

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