• Title/Summary/Keyword: Science Preparation

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Transmission Electron Microscope Sampling Method for Three-Dimensional Structure Analysis of Two-Dimensional Soft Materials

  • Lee, Sang-Gil;Lee, Ji-Hyun;Yoo, Seung Jo;Datta, Suvo Jit;Hwang, In-Chul;Yoon, Kyung-Byung;Kim, Jin-Gyu
    • Applied Microscopy
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    • v.45 no.4
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    • pp.203-207
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    • 2015
  • Sample preparation is very important for crystal structure analysis of novel nanostructured materials in electron microscopy. Generally, a grid dispersion method has been used as transmission electron microscope (TEM) sampling method of nano-powder samples. However, it is difficult to obtain the cross-sectional information for the tabular-structured materials. In order to solve this problem, we have attempted a new sample preparation method using focused ion beam. Base on this approach, it was possible to successfully obtain the electron diffraction patterns and high-resolution TEM images of the cross-section of tabular structure. Finally, we were able to obtain three-dimensional crystallographic information of novel zeolite nano-crystal of the tabular morphology by applying the new sample preparation technique.

Effect of Dextran Gel on Preparation of Nano-liposomes Loaded with Ginkgolide

  • Tong, Yuan;Chen, Yan;Pan, Jian;Huang, Li;Wang, Ruijun
    • Bulletin of the Korean Chemical Society
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    • v.31 no.9
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    • pp.2542-2546
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    • 2010
  • The objective of this paper was to investigate the effect of dextran gel on preparation of nano-liposomes loaded with ginkgolide. During preparation, Sephadex G75, G50 and G25 were added in the aqueous phase respectively. From the experiment, nano-liposomes prepared by dextran gels were found spherical and smooth. The result indicated that aperture of dextran gels were narrower, particle size of nano-liposomes was smaller (207.13 ~ 89.16 nm) and zeta potential was greater (-36.2 ~ -29.5 mV) in more negative. The study also revealed that differences of the entrapment efficiency and drug loading among the three types of nano-liposomes were not significant. In vitro drug release test demonstrated that nano-liposomes had a better controlled release. To conclude, by using dextran gel in the preparation of nano-liposome loaded with ginkgolide, the particle size could be effectively controlled and the drug stability could be improved.

Information Needs of Korean Immigrant Mothers in the United States for Their Children's College Preparation

  • Yoon, JungWon;Taylor, Natalie;Kim, Soojung
    • Journal of Information Science Theory and Practice
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    • v.6 no.4
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    • pp.54-64
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    • 2018
  • This study aims to understand the information needs of Korean immigrant mothers in the United States for their high school children's college preparation. A content analysis was conducted for the messages posted to a "motherhood" forum on the MissyUSA website. In total, 754 posts were analyzed in terms of a child's grade, college preparation stage, type of post, and topic of post. The study found that there is a range of information needed at different stages in a child's education. Many of the demonstrated information needs showed similarities to those of other immigrant groups, but there were also community-specific themes, such as an emphasis on STEM (science, technology, engineering, and math) and standardized tests. The forum was mainly used for factual questions, not emotional support. We concluded that the findings of the study would help researchers in understanding immigrant information needs for the college application process and how information professionals and educators could combine the needs of different ethnic groups to create customized services for them.

Factors Affecting the Preparation for Later Life According to Age in Production Workers (생산직 근로자의 연령별 노후준비와 영향요인)

  • Kim, Hyun-Mi;Choi, Yeon-Hee
    • Korean Journal of Occupational Health Nursing
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    • v.19 no.2
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    • pp.117-127
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    • 2010
  • Purpose: The purpose of this study was to investigate the factors that influenced the preparation for later life of the age group of 30s, 40s, and 50s in production workers. Methods: The participants for this study were 320 men working in 2 workspaces of Ulsan city. The data was collected from May to July, 2010 using structured questionnaires. Chi-square, One way ANOVA, Duncan test, Pearson's Correlation Coefficient and multiple regression with the SPSS WIN 17.0 program were used to analyze the data. Results: There were statistically significant differences among 30s, 40s, and 50s workers regarding the preparation for later life, health promoting behavior, knowledge and attitude of cerebrocardiovascular (CVD) diseases. 50s workers were significantly more higher than 30s and 40s regarding the preparation for later life, health promoting behavior, cognition and attitude of CVD diseases. The model including variables related to the preparation for later life explained variance of 42.3% of 30s, 36.0% of 40s, and 28.5% of 50s workers. Finally, cognition of CVD diseases and social support were predictors in explaining the level of the preparation for later life among production workers. Conclusion: Based on the findings of the study, nursing interventions should be developed to improve the preparation for later life of production workers according to age differences.

A Study on Influence of Physical Preparation for Later Life on Social Relationship after Retirement: Focusing on Moderating Effect of Leisure Life

  • KIM, Jong-Jin
    • The Journal of Industrial Distribution & Business
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    • v.10 no.10
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    • pp.7-13
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    • 2019
  • Purpose - This study is to verify the mediating effect of voluntariness in retirement and the moderating effects of leisure life to examine which parts of later life preparations have influence on the retired life. Research design, data, and methodology - In this study, the 6th Korean Retirement and Income Study was conducted on 5,254 members of households with householders over the age of 50. To examine the relationship between later life preparation and retired life, this study used personal data based on the serial number of the household members. Results - First, physical preparation for later life had a positive influence on retired life satisfaction among retirement satisfaction. People showed higher retired life satisfaction. Secondly, physical preparation for later life had a positive influence on satisfaction over relationship after retirement among retirement satisfaction. People showed higher satisfaction over relationship after retirement when they were more physically prepared for later life. Conclusions - In particular, leisure life had a mediating effect for the influence of physical preparation for later life on the retired life. Also, leisure life and physical preparation for later life showed a close influencing relationship. People showed active leisure life and higher retired life satisfaction when they were more physically prepared for later life.

The effect of laser energy on the preparation of iron oxide by a pulsed laser ablation in ethanol

  • Maneeratanasarn, P.;Khai, T.V.;Choi, B.G.;Shim, K.B.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.22 no.3
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    • pp.134-138
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    • 2012
  • Recently the preparation magnetic nanoparticles by a pulsed laser ablation in liquid has gained much attention because it is easy to control experimental parameters. Iron oxide magnetic nanoparticles have been prepared by a pulsed laser ablation of ${\alpha}-Fe_2O_3$ target in ethanol at different magnitude of laser energy of 1, 20, 40 and 80 mJ/pulse. It revealed that particle size increases with increasing laser energy. It could be concluded that 40 mJ/pulse is an optimum laser energy for the preparation of iron oxide nanoparticles with uniform size distribution. The nanoparticles are homogeneously dispersed in ethanol and their stability maintained for several months.

Transmission Electron Microscopy Specimen Preparation for Layer-area Graphene by a Direct Transfer Method

  • Cho, Youngji;Yang, Jun-Mo;Lam, Do Van;Lee, Seung-Mo;Kim, Jae-Hyun;Han, Kwan-Young;Chang, Jiho
    • Applied Microscopy
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    • v.44 no.4
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    • pp.133-137
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    • 2014
  • We suggest a facile transmission electron microscopy (TEM) specimen preparation method for the direct (polymer-free) transfer of layer-area graphene from Cu substrates to a TEM grid. The standard (polymer-based) method and direct transfer method were by TEM, high-resolution TEM, and energy dispersive X-ray spectroscopy (EDS). The folds and crystalline particles were formed in a graphene specimen by the standard method, while the graphene specimen by the direct method with a new etchant solution exhibited clean and full coverage of the graphene surface, which reduced several wet chemical steps and accompanying mechanical stresses and avoided formation of the oxide metal.

Effect of Coffee-like Green Tea Preparation on Cytotoxicity of Human Cancer and Normal Cells (Coffee-like green tea의 인체암세포 및 정상세포에 대한 독성)

  • Moon, Yean Guy;Kwon, Jung Min;Kim, Jong Cheol;Park, Han Min;Cho, Yong Un;Jung, Kwan Ju;Ha, Yeong Lea
    • Journal of Life Science
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    • v.23 no.1
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    • pp.84-94
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    • 2013
  • The cytotoxicity of coffee-like green tea (CLGT) was determined in a human breast cancer cell line, MCF-7; a human prostate cancer cell clone, PC-3; a human neuroblastoma cell line, SK-N-SH; and a rat cardiomyoblast cell line, H9c2, with reference to green tea leaves (GTL). The CLGT was prepared by roasting the GTL for 60 min at $240^{\circ}C$ in a temperature-controlled frying pan. The CLGT preparation imitated the flavor and taste characteristics of coffee fairly well according to sensory analysis. The CLGT preparation had no adverse cytotoxic effects on the cancer cells or the normal cells compared to GTL. No significant change in the antioxidant activity was seen in the CLGT preparation compared to that of GTL. The amount of total protein, sugar, and phenolic compounds was reduced in the preparation relative to those in GTL, a fact that might explain the coffee-like flavor and/or taste characteristics of the CLGT preparation. These results suggest that CLGT prepared by roasting GTL for 60 min at $240^{\circ}C$ does not show any adverse effects on cancer cells and normal cells compared to GTL. They imply that CLGT could be safe for human consumption.

The Effects of Growth Mindset and Self-leadership on Career Preparation Behavior in Senior Nursing Students (졸업학년 간호대학생의 성장마인드셋과 셀프리더십이 진로준비행동에 미치는 영향)

  • Kim, Eun-A
    • Journal of the Korean Applied Science and Technology
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    • v.39 no.4
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    • pp.499-506
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    • 2022
  • This study is a descriptive research study that attempted to investigate the effects of growth mindset and self-leadership on career preparation behavior of senior nursing students. The data collection period is from November 1 to 30, 2021, and the subject of the study is 173 nursing students from three universities located in G city and J province. For data analysis, t-test, ANOVA, descriptive analysis, Pearson's correlation, and controlled regression analysis were performed using the SPSS 26.0 program. As a result of the study, self-leadership(𝛽=.435, p<.001) and growth mindset(𝛽=.193, p=.005) had a positive effect on career preparation behavior and explained career preparation behavior by 32.0%. Therefore, it suggests that a practical strategy for cultivating self-leadership and growth mindset is necessary to promote career preparation behavior of senior nursing students.

An Analysis of the Premarital Preparation Education Program (결혼준비교육 프로그램의 분석)

  • Moon Sook-Jae;Jung Young-A;Yoon So-Young
    • Journal of Family Resource Management and Policy Review
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    • v.10 no.1
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    • pp.33-51
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    • 2006
  • Today, the Korean society is experiencing an increase in serious problems, such as child abuse, unmarried mothers, single mothers, which cannot be overlooked as simply trivial family matters. The increase in these problems is caused by the rapid change that has taken place within our society, which has emasculated the power of our traditional values and behavior patterns to cope with contemporary life styles. Premarital Preparation Education is starting to gain attention as a preventive measure that can overcome this serious family crisis. Although the importance of the Premarital Preparation Education program cannot be overemphasized, there are only few cases where engaged couples and unmarried men and women are exposed to this type of program and actually experience its benefits. In other words, there is an urgent need to revitalize and increase the effects of the Premarital Preparation Education Program. This research was conducted in order to find a way to revitalize and to increase the effects of the program, so that more and more people can participate and receive benefits from it. First, we have analyzed the program's contents and the current condition on how the program is actually conducted. Then we have compared real case examples of the program and analyzed the current situation and its problems.

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