• Journal of Periodontal and Implant Science
• /
• v.28 no.4
• /
• pp.577-604
• /
• 1998

chitosan은 골치유증진 및 골세포의 분화를 촉진하는 것으로 알려진 천연의 생분해성 고분자이다. 이연구에서는 chitosan 및 chitosan/tricalcium phosphate(TCP) 다공성 기질을 제조하여 골이식재 및 조직공학적 골형성을 위한 3차원적 세포배양 지지체로서의 가능성을 평가하고자 하였다. chitosan 용액 및 TCP가 포함된 chitosan 용액을 동결건조함으로써 소공의 크기가 $100-200{\mu}m$인 스폰지형태의 chitosan 및 chitosan/TCP 다공성 기질을 제작하였다. 골이식재로서의 효과를 평가하기 위하여 백서의 두개골 결손부에 제작된 chiosan 및 chitosan/TCP 다공성 기질을 각각 이식하고 2주 및 4주 후에 동물을 희생하여 조직학적으로 치유양상을 관찰하였다. 조직공학적 골형성을 위한 세포배양 지지체로서의 가능성을 평가하기 위하여 백서 태자의 두개골에서 분리된 골아세포를 chitosan 및 chitosan/TCP 다공성 기질에 각각 접종하고 56일간 배양하면서 각 기간 별로 세포수, 염기성 인산효소 활성, 축적된 calcium의 양을 측정하였고 배양된 세포-기질 혼합체를 광학현미경 및 주사전자현 미경하에서 조직학적 관찰을 시행하였다. 백서 두개골결손부에 이식된 chitosan 및 chiosan/TCP 다공성 기질은 별다른 이물반응 없이 자연 분해되면서 신생골조직 내에 매립되었으며 이식하지 않은 대조군에 비해 유의하게 높은 신생골형성 효과를 나타내어 우수한 골전도성이 있음이 확인되었다. 신생골형성 양상이나 형성된 양에 있어서 두 가지 기질간의 유의한 차이는 없었다. 골아세포-기질 혼합체의 배양결과, 접종후 배양 28일 경과 시까지 골아세포수는 지속적으로 증가하다가 이후에는 5 8일까지 성장정도가 둔화되었다. 염기성 인산효소의 활성 및 calcium 축적량은 접종후 배양시간경과에 따라 56일까지 지속적으로 증가하였다. 세포수 및 염기성 인산효소의 활성에서 두 기질간의 유의한 차이는 없었고, calcium 축적량에 있어서는 chitosan/TCP 기질에서 유의하게 높았고 증가속도도 컸다. 배양된 골아세포가 접종된 다공성 기질의 조직학적 관찰결과, 골아세포는 다공성 기질에 잘 부착하여 중층의 형태로 성장하면서 광화된 골기질을 형성함이 관찰되었다. 배양 14일부터 작은 골편형태의 골형성이 기질 표면에 부착되어 관찰되었고, 배양기간이 길어짐에 따라 성장하여 배양 56일째에는 상당한 양의 광화된 골질이 형성됨이 관찰되었다. 배양 56일 경과후의 광화된 골질의 양은 chitosan/TCP 기질에서 더 많았다. 이 연구의 결과, chitosan 및 chitosan/TCP 다공성 기질이 골이식재로서 뿐만 아니라, 조직공학적 골형성에 적용되는 골아세포의 배양을 위한 3차원구조의 세포지지체로 이용되어 골재생술식에 유용한 생체재료로 활용될 수 있음이 확인되었다.

• The Journal of Korean Institute for Practical Engineering Education
• /
• v.3 no.2
• /
• pp.147-157
• /
• 2011

This study was conducted to investigate haw coaching leadership affects organizational members' career planning and attitudes; organizational commitment, job satisfaction and turnover intention. For this purpose, this study used as its subjects at the major companies and subsidiary companies in Korea. The independent variable coaching leadership composed of the 5 factors; guidance, facilitation, inspiration, listening and questioning. The result of the study, coaching leadership was shown to have a significant effect on career planning, organizational commitment, job satisfaction and turnover intention. The case of coaching leadership is being more, the level of career planning, organizational commitment and job satisfaction are increased and the level of turnover intention are decreased. The findings of this study are particularly important because they contribute the evidence that support the effects of coaching leadership development program in the company.

• Journal of Digital Convergence
• /
• v.19 no.7
• /
• pp.155-162
• /
• 2021

The purpose of this study is to investigate effects of management support for health and safety on workers' safety perception. Since the 1990s, Korea's national competitiveness has been rising rapidly, but efforts to prevent and cope with industrial accidents are still insufficient. Particularly there is a big movement to strengthen corporate responsibility for serious accidents in the 2020s. In this study structural equation model(SEM) was constructed and quantitatively analyzed in order to know how management's support affects the organization, system, and communication related to safety and health in the company, and ultimately how it has an effect on workers' safety perception. 4,169 questionnaires conducted by the Institute for Occupational Safety and Health were used as observation variables, and 5 hypotheses were established and were verified in SEM. As management support increases, organization & institution for a safe workplace, communication related with safety and health within the company become more active. Finally management support has a positive effect on workers' safety perception. The results of this study imply that management needs to increase awareness of the importance of safety and health before all measures such as organizations, institutions, and communication related to safety and health.

• Korean Journal of Adult Nursing
• /
• v.22 no.6
• /
• pp.606-614
• /
• 2010

Purpose: The purpose of this study was to identify the predictors of Organizational Citizenship Behavior (OCB) among hospital nurses. Methods: Participants in this study were 231 nurses from two hospitals. The self-reported questionnaire was used to assess the level of self-efficacy, social support and OCB. The data were analyzed using descriptive statistics, Pearson's correlation coefficient, t-test, ANOVA and multiple regression. Results: The mean score of OCB was 4.82, self-efficacy was 4.65, and social support was 4.56. The OCB was statistically significant according to position (t=-1.97, p=.049). The OCB was positively correlated with self-efficacy (r=.558, p<.001) and social support (r=.245, p<.001). The self-efficacy and social support explained 33.0% of the variance for OCB. Conclusion: The findings suggest that developing programs to improve self-efficacy and social support might be useful. Furthermore, more studies are needed to explore variables that influence nurses' Organizational Citizenship Behavior.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.20 no.4
• /
• pp.115-125
• /
• 2012

The purpose of this study is to investigate the relationship between organizational culture(constructive and defensive culture) and emotional labor along with the social supports (supervisor support, colleague support). Using data obtained from a survey of 419 flight attendants of a major airline company in south Korea. The results are as follows: Organizational culture had a significant effect on emotional labor. At this point, colleague support mediated the relationship between constructive culture and emotional labor. In addition, supervisor support and colleague support had a mediating role between defensive culture and emotional labor. This result concludes that flight attendants positively accept the essential manuals and safety regulations in the special working condition with a unified team service. Furthermore, the results show that social supports are an important job resource for flight attendants helping them reach their work-related goals.

• Polymer(Korea)
• /
• v.32 no.6
• /
• pp.516-522
• /
• 2008

Biodegradable polymers have been used extensively as scaffolding materials to regenerate new tissues and the ingrowth of tissue have been reported to be dependent directly of the porosity, pore diameter, pore shape, and porous structure of the scaffold. In this study, porous poly (L-lactide-co-glycolide) (PLGA) scaffolds with five different pore sizes were fabricated to investigate the effect of pore sizes for AF tissue regeneration. Cellular viability and proliferation were assayed by MTT test. Hydroxyproline/DNA content of AF cells on each scaffold was measured. sGAG analyses were performed at each time point of 2 and 6 weeks. Scaffold seeded AF cells were implanted into the back of athymic nude mouse to observe the difference of formation of disc-like tissue depending on pore size in vivo. We confirmed that scaffold with $180{\sim}250{\mu}m$ pores displayed high cell viability in vitro and produced higher ECM than scaffold with other pore sizes in vivo.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.39 no.12
• /
• pp.1229-1235
• /
• 2015

Scaffold fabrication technology using a 3D printer was developed for damaged bone tissue regeneration. A scaffold for bone tissue regeneration application should be biocompatible, biodegradable, and have an adequate mechanical strength. Moreover, the scaffold should have pores of satisfactory quantity and interconnection. In this study, we used the polymer deposition system (PDS) based on fused deposition modeling (FDM) to fabricate a 3D scaffold. The materials used were polycaprolactone (PCL) and alginic acid sodium salt (sodium alginate, SA). The salt-leaching method was used to fabricate dual pores on the 3D scaffold. The 3D scaffold with dual pores was observed using SEM-EDS (scanning electron microscope-energy dispersive spectroscopy) and evaluated through in-vitro tests using MG63 cells.

• Proceedings of the KAIS Fall Conference
• /
• 2008.11a
• /
• pp.488-491
• /
• 2008

본 연구에서는 가전제품 서비스 엔지니어의 직무만족도가 계속근무의사에 어떠한 영향을 미치는 지를 조사 분석하였다. 또한 직무만족도에 영향을 미치는 요인이 무엇인지를 조사 분석하였다. 그 결과 엔지니어 개인적 특성에 있어서는 성격이 직무만족도에 영향을 미치는 요인으로 파악되었으며, 조직적 특성에 있어서는 사회적 지지와 급여 및 복리후생이 영향을 미치는 요인으로 분석되었다. 직무 자체의 특성에 있어서는 업무 적정성이 직무만족도에 영향을 미치는 것으로 파악되었다. 또한 이러한 직무만족도는 계속근무의사에 의미있는 영향을 미치는 것으로 조사 분석되었다.

• Polymer(Korea)
• /
• v.39 no.3
• /
• pp.412-417
• /
• 2015

A critical element in tissue engineering approaches is a control of the mechanical properties of polymer scaffolds to regulate cell phenotype, which may lead to clinically successful tissue regeneration. In this study, we hypothesized that gel stiffness could be a key factor to manipulate adhesion and proliferation of different types of cells. RGD-modified alginate gels with various mechanical properties were prepared and used as a substrate for MC3T3-E1 and H9C2 cells. Adhesion and growth rate of MC3T3-E1 cells in vitro were increased in parallel with an increase of gel stiffness. In contrast, those of H9C2 cells were decreased. This approach to control the mechanical properties of polymer scaffolds depending on the cell types may find useful applications in the tissue engineering.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.2
• /
• pp.27-33
• /
• 2021

The purpose of this study was to investigate the influence of clinical nurses' sleep disorder, organizational support, and health promotion behaviors on professional quality of life. The subjects were 256 nurses working in hospitals in more than 200 and less than 300 beds hospital in B and G cities. The data were collected from September 4, 2017 to September 11, 2017. The collected data were analyzed by frequency analysis t-test, ANOVA, Scheffé test, Pearson's correlation coefficients, and multiple regression analysis using SPSS WIN 20.0. Burnout rate was 28.90± 4.00, burnout was associated with sleep disorder(r=-.321, p<.001), organizational support(r=-.321, p<.001), health promoting behavior(r=-,519 p<.001) showing a negative correlation. The factors affecting burnout were organizational support(β=-.113, p=.045), sleep disorder(β=-.129, p<.040), gender(β=-.131, p=.024), health promotion behaviors(β=-.423, p<.001) and the explanatory power was 32.2%. Based on these results, we aim to provide basic data for the development of various programs that can control burnout of nurses.