• Title/Summary/Keyword: Lee Sam

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Derivation of primordial germ cells from chicken blastodermal cells by BMP-2 and BMP-4 signaling

  • Kim, Duk-Kyung;Song, Ki-Duk;Lee, Young-Mok;Seo, Sam-Youl;Han, Jae-Yong
    • Proceedings of the Korea Society of Poultry Science Conference
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    • 2002.11a
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    • pp.96-97
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    • 2002
  • Primordial germ cells (PGCs) are the progenitors of the sperms or eggs of adult. Evidence suggests that the specification of primordial germ cells (PGCs) in the mammalian embryo does not depend on maternal determinants. Recent previous studies in the mouse has shown that several bone morphogenetic proteins (BMPs) are required for the formation of PGCs. However, there is no study about the effect of BMPs on avian PGCs. Here, we studied the effects of recombinant human BMP-2 (rhBMP-2) and recombinant human BMP-4 (rhBMP-4) on chicken blastodermal cells in culture. As a results, the addition of rhBMP-2 and rhBMP-4 increased the number of SSEA-1 positive cells in dose-dependent manner. However, there is no synergic effect by using both rhBMP-2 and rhBMP-4.

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Measuring the Service Quality of Mobile Internet and Studying the Effects on Marketing Performance (모바일 인터넷 서비스 품질 측정 및 마케팅 성과에 미치는 영향 연구)

  • Park, Yoon-Seo;Lee, Seung-In;Kim, Sam-Kwon;Yang, Liu
    • Journal of Korean Society for Quality Management
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    • v.35 no.2
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    • pp.63-83
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    • 2007
  • As the mobile internet service market is rapidly growing, measuring and managing the service quality become a more critical issue to the service providers. Thus the purpose of this study is to compare SERVQUAL, SERVPERF, and non-difference score measures and to determine which one is superior to measure the service quality of the mobile internet service. This study also aims to analyze the structural relationship between the service quality, customer satisfaction and behavioral intentions (repurchase intention and word-of-mouth). For the purpose, survey data were gathered from the respondents who have used the mobile internet services and an empirical test was conducted. As the first research result, it was revealed that the non-difference score measure showed a much better model than other service measuring models (SERVQUAL, SERVPERF). And the second result was that two service quality factors (tangibles and empathy) among the mobile internet service quality factors significantly influenced the customer satisfaction and also the customer satisfaction had a significant effect on the repurchase and word-of-mouth.

Design and Implementation of Polymer-Light Emitting Diodes by using Nanocantact Printing (나노접촉 인쇄공정을 이용한 폴리머 유기정보표시소자 설계 및 구현)

  • Jo Jeong-Dai;Kim Kwang-Young;Lee Eung-Sug;Choi Byung-Oh
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.1511-1513
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    • 2005
  • The polymer-light emtting diodes(PLEDs) were comprised a design of OLED array, process develop by using ITO thin glass, and fabrication of PDMS stamp by using nanocontact printing. In the study, we describe a different approach for building OLEDs, which is based on physical lamination of thin metal electrodes supported by a PDMS stamp layer against an electroluminescent organic. We develop that devices fabricated in this manner have better performance than those constructed with standard processing techniques. The lamination approach avoids forms of disruption that can be introduced at the electrode organic interface by metal evaporation and has a reduced sensitivity to pinhole or partial pinhole defects. Also, it is easy to build patterned PLED with feature sizes into the nanometer regime. This method provides a new route to PLED for applications ranging from high performance displays to storage and lithography systems, and PLED can used for organic electronics and flexible display.

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Kinematical analysis of Yurchenko Streched at Horse Vaulting (도마운동 유리첸코 몸 펴 공중돌기 동작의 운동학적 분석)

  • Yoon, Chang-Sun;Kim, Tae-Sam;Yoon, Hee-Joung
    • Korean Journal of Applied Biomechanics
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    • v.13 no.3
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    • pp.67-79
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    • 2003
  • The purpose of this study is to investigate the effective skill motion through the kinematic analysis of the Yurchenko Streched motion in new horse vaulting. The subjects in this study were 3 male gymnasts who were ranked as national athletes. After the 3D motion analysis, kinematic variables were analyzed to comparison with the difference between this study and the previous study(Yang, D. Y and Lee, C. S, 1999). As a result, the following conclusions was drawn; 1. In the board contact phase, this study showed a shorten contact time to maintain in condition highly extension of hip and hee angle than the previous study. 2. In the pre-flight phase, this study appeared more shortly flight duration time and horizontal flight displacement than the previous study. 3. In the horse contact phase, the contact duration time and horizontal displacement of COG shortened than the previous study, but appeared to the fast horizontal and vertical velocity and highly extension of shoulder an. 4. In the post-flight phase, a stable horse contact appeared to the increase of the flight duration time and the apex height during the post-flight. And it showed that these results have a stable and good landing.

The Relationship between the Distance and Release Parameters in Korean Female Javelin Throwers (한국 여자 창던지기 선수들의 기록과 릴리즈 요인과의 관계)

  • Kim, Tae-Sam;Ryu, Ji-Seon;Lee, Soon-Ho
    • Korean Journal of Applied Biomechanics
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    • v.22 no.2
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    • pp.131-140
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    • 2012
  • This study was to investigate the relationship between the distance and projection factors, angle factors of javelin in women's javelin throwing. The data were collected in the 2011 National Sports Festivals for 11 players. Three-Dimensional motion analysis using a system of 4 video cameras at a sampling frequency of 60 fields/s was performed for this study. The factors of release conditions calculated using Matlab 2009a program. The statical analysis on the records(n=42) included mean and standard deviation of the mean(SD), Pearson's product moment correlation coefficient(SPSS Version 16.0 for Windows). There was a statistically significant positive relationship between the records and release velocity(r=.866, p<.01), height(r=.433, p<.01) and height rate(r=.340, p<.05). The attitude angle, release angle, and attack angle showed not a statistically significant relationship between the records. The medial-lateral tilt angle of javelin showed not a statistically significant relationship between the records, but the yaw angle of javelin(r=.549, p<.01) showed a statistically significant positive relationship between the records.

Correlation between Body Weight and Colony Development of the Bumblebee Queen, Bombus ignitus

  • Yoon, Hyung Joo;Kim, Sam Eun;Lee, Sang Beom;Park, In Gyun;Seol, Kwang Youl
    • International Journal of Industrial Entomology and Biomaterials
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    • v.9 no.1
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    • pp.95-99
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    • 2004
  • This study was carried out to investigate the effect of body weight of queen on the developmental characteristics of foundation queens in the Bombus ignitus collected in Korean locality. Queens were classified into six groups based on their body weight (i.e., 0.4 g, 0.5 g, 0.6 g, 0.7 g, 0.8 g and 0.9 g). The average weight of 200 foundation queens collected was 0.657${\times}40.095 g and 0.6 g-class was most abundant (38 %) among six weight classes. The queen that had the heavy body weight showed the trends of higher rate of oviposition, colony foundation and progeny-queen production and shorter periods of preoviposition and colony foundation, suggesting the positive correlation between the body weight of queen and colony developmental characteristics. Also, the numbers of worker and progeny-queen emerged from the queen with heavy body weight were slightly higher than those with light body weight queen.

Development of functional cosmetic powder using silkgland powder of silkworm (누에실샘 미세분말을 이용한 기능성 색조용 파우더 개발)

  • Chon, Jeong-Woo;Kweon, HaeYong;Jo, You-Young;Yeo, Joo-Hong;Park, Myung-Ki;Son, Yong-Ho;Lee, Heui-Sam
    • Journal of Sericultural and Entomological Science
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    • v.51 no.1
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    • pp.41-47
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    • 2013
  • In this study, silkgland powder of silkworm were investigated to see possibility for cosmetic powder materials. To test possibility as a baby powder cosmetics, total content rate of amino acids, DPPH free radical scavenging assay, MTT assay, and clinical trial were done. According to the result of the analysis of the amino acids of silkgland powder, serin (26.77%) content was the highest and asparatic acid (15.47%), and glycine (9.62%) were followed. DPPH free radical scavenging activity of silkgland powder was lower than vitamin C by 82.3% and 97%, respectively, which is relatively good. And the moisture and elasticity effect were increased in silkgland powder compared to control cosmetics by 210% and 185%, relatively. Thus, these results suggest that silkgland powder of silkworm may have beneficial properties as a material for cosmeceuticals.

Effect of ${\beta}$-Glucan Originated from Aureobasidium on Infected Dermal Wound Healing of the Normal Nude Mouse (Aureobasidium 유래 ${\beta}$-Glucan의 Nude Mouse 감염 피부에 대한 창상 치유 효과)

  • Lee, Jung-Woo;Kwon, Young-Sam;Jang, Kwang-Ho
    • Journal of Veterinary Clinics
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    • v.29 no.6
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    • pp.464-469
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    • 2012
  • This experiment was applied to examine the effects of ${\beta}$-glucan originated from Aureobasidium on wound healing infected by 3 strains of bacteria in the normal nude mouse. From the results it was suggested that ${\beta}$-glucan has properties, which may be beneficial in the treatment of wound healing though it does not showed any antibacterial activities against wound infections by three strains such as S. aureus, S. pyogenes and P. aeruginosa. Therefore, it is considered that ${\beta}$-glucan will be promised as a new wound management.

Diagnosis of swine sarcoptic mange(Sarcoptes scabiei var. suis) by ELISA (ELISA를 이용한 돼지 옴 (Sarcoptes scabiei var. suis) 감염증의 진단)

  • Jee, Cha-Ho;Lee, Sam-sun;Chang, Lai-hun
    • Korean Journal of Veterinary Research
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    • v.41 no.4
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    • pp.565-570
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    • 2001
  • The diagnosis of swine sarcoptic mange (Sarcoptes scabiei var. suis) was investigated by ELISA in order to replace current diagnostic methods such as skin scraping, scratching index, or lesion score of dermatitis. The current methods need many efforts and much times and cost much. They can not handle many samples simultaneously. Therefore, in this research we developed ELISA that can handle many samples at a time. The antigens of swine sarcoptic mite were isolated and examined by 12.5% SDS-PAGE and silver staining. The antigenicity of antigen was confirmed by Western blotting using the swine from the artificailly-infested swine with swine sarcoptic mite. The optical density (OD) values of the artificailly-infested positive sera and the naturally-infested positive sera of sows were measured and read in order to confirm the stability of antigens, the reproducibility and validity (sensitivity and specificity) of the manufactured ELISA of swine sarcoptic antigens. In above results, the developed ELISA would be possible to use the diagnostic tool of sarcoptic mange if OD values of piglets, fattening pigs and sows are interpreted reasonably and classified as mange-free and infested.

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Response of dairy cows to glucose administration (유우(乳牛)에 있어서 포도당(葡萄糖) 투여(投與)의 반응(反應)에 관(關)한 실험적(實驗的) 연구(硏究))

  • Sakai, Takeo;Yoon, Chong-sam;Satoh, Tsuneo;Lee, Won-chang
    • Korean Journal of Veterinary Research
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    • v.33 no.1
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    • pp.145-149
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    • 1993
  • 실험대상(實驗對象)으로서 유우(乳牛) 5두(頭)에게 50% 포도당(葡萄糖) $500m{\ell}$를 생리적식염수(生理的食鹽水)에 혼합(混合) 13~15회(回) 반복(反復) 경정맥(jugular vein)을 통해 주입후(注入後) 혈중(血中) insulin수준(水準)과 Langerhans islets의 조직화학(組織化學)을 관찰(觀察)한바, 혈중(血中) insulin의 수준(水準)은 포도당(葡萄糖)의 투여전(投與前)에 비(比)하여 4~11배(倍)나 증가(增加)됨이 관찰(觀察)되었다. 한편, Langerhans islet의 B cell도 포도당(葡萄糖)의 투여회수(投與回數)에 따라 특이(特異)하게 주름이 관찰(觀察)되었는데 이는 B cell에서의 insulin 합성능(合成能)을 높이는데 그 원인(原因)이 있었다고 본다.

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