• Title, Summary, Keyword: qualitative study

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MICROHARDNESS AND SURFACE ROUGHNESS OF SEALANT AND FLOWABLE COMPOSITE RESINS (치면열구전색제와 유동성 복합 레진의 미세 경도 및 표면 조도의 비교)

  • Yang, Kyu-Ho;Choi, Nam-Ki;Kim, Seon-Mi;Choi, Ji-Eun
    • JOURNAL OF THE KOREAN ACADEMY OF PEDTATRIC DENTISTRY
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    • v.36 no.3
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    • pp.440-447
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    • 2009
  • This study was performed to compare the wear resistance of sealant and flowable resins for analyzing the effect of flowable resin as a sealant in preventive resin restorations. Specimens were made and Vicker's hardness number and surface roughness were measured. SEM observations of the polished and abraded surfaces were established. Kruskal-Wallis rank test and Mann-Whitney U test at the significant level of ${\alpha}$=0.05 were used. The following results were obtained: 1. The microhardness was decreased among groups in following order: Z350 (3M ESPE, U.S.A), Estelite (Tokuyama Dental, Japan) and Ultraseal (Ultradent, U.S.A). There were significant differences in all groups (p<0.0001). 2. The surface roughness was decreased among groups in following order: Ultraseal XT plus, Palfique Estelite LV and Filtek Z350 flowable. However, there is no statistically significant differences in roughness among Estellite, Z350 and Ultraseal at the significance level of ${\alpha}$=0.05, with p=0.116 3. SEM observation of the unworn and worn surfaces revealed the qualitative differences in the wear appearance among groups. The results in this study indicate that flowable resin is better than sealant in aspect of physical properties.

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Survey of Beet Red Contents in Foods using TLC, HPLC (TLC, HPLC를 이용한 식품 중 비트레드 함량조사)

  • Jang, Yaung-Mi;Lee, Tal-Soo;Hong, Ki-Hyoung;Park, Sung-Kwan;Park, Sung-Kug;Kwon, Yong-Kwan;Park, Jae-Seok;Chang, Sun-Young;Hwang, Hye-Shin;Kim, Eun-Jeong;Han, Yeun-Jeong;Kim, Byung-Sub;Won, Hye-Jin
    • Journal of Food Hygiene and Safety
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    • v.20 no.4
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    • pp.244-252
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    • 2005
  • This study was performed far development of new analytical method of beet red in foods. In this study, analysis of beet red in foods has been carried out by detection of betanine and isobetanine, the main color component of beet red as indicator compounds. The qualitative analysis technique consisted of clean-up of the colors with a $C_{18}$ cartridge, separation of the colors by cellulose TLC plate using acetone:3-methyl-1-butanol:distilled water (7:7:6) as a solvent system. Also, the quantitative analysis was performed using X-terra RP at wavelength 538 nm and $0.1\%$ phosphoric acid : methanol (90:10) as a solvent. The quantitative results of beet .ed were as follows:900.22$\∼$27701.60 $\mu$g/g for 60 item in nutrient supplement food, $21.95\∼713.40{\mu}g/g$ for 30 items and N.D. for 18 items in cindy, and $155.85{\∼}505.37{\mu}g/g$ for 12 items in ice creams, $43.52\∼64.75{\mu}g/g$ for 18 items and N.D. for 54 item in sauce, N.D. for 12 items in retort food.

Method Development for the Profiling Analysis of Endogenous Metabolites by Accurate-Mass Quadrupole Time-of-Flight(Q-TOF) LC/MS (LC/TOFMS를 이용한 생체시료의 내인성 대사체 분석법 개발)

  • Lee, In-Sun;Kim, Jin-Ho;Cho, Soo-Yeul;Shim, Sun-Bo;Park, Hye-Jin;Lee, Jin-Hee;Lee, Ji-Hyun;Hwang, In-Sun;Kim, Sung-Il;Lee, Jung-Hee;Cho, Su-Yeon;Choi, Don-Woong;Cho, Yang-Ha
    • Journal of Food Hygiene and Safety
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    • v.25 no.4
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    • pp.388-394
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    • 2010
  • Metabolomics aims at the comprehensive, qualitative and quantitative analysis of wide arrays of endogenous metabolites in biological samples. It has shown particular promise in the area of toxicology and drug development, functional genomics, system biology and clinical diagnosis. In this study, analytical technique of MS instrument with high resolution mass measurement, such as time-of-flight (TOF) was validated for the purpose of investigation of amino acids, sugars and fatty acids. Rat urine and serum samples were extracted by selected each solvent (50% acetonitrile, 100% acetonitrile, acetone, methanol, water, ether) extraction method. We determined the optimized liquid chromatography/time-of-flight mass spectrometry (LC/TOFMS) system and selected appropriated columns, mobile phases, fragment energy and collision energy, which could search 17 metabolites. The spectral data collected from LC/TOFMS were tested by ANOVA. Obtained with the use of LC/TOFMS technique, our results indicated that (1) MS and MS/MS parameters were optimized and most abundant product ion of each metabolite were selected to be monitorized; (2) with design of experiment analysis, methanol yielded the optimal extraction efficiency. Therefore, the results of this study are expected to be useful in the endogenous metabolite fields according to validated SOP for endogenous amino acids, sugars and fatty acids.

Correlation Analysis of Diffusion Metrics (FA and ADC) Values Derived from Diffusion Tensor Magnetic Resonance Imaging in Breast Cancer (유방암의 확산텐서 자기공명 영상에서 유도된 확산 지표(FA, ADC) 값의 연관성 분석)

  • Lee, Jae-Heun;Lee, Hyo-Yeong
    • Journal of the Korean Society of Radiology
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    • v.12 no.6
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    • pp.755-762
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    • 2018
  • The purpose of this study was to compare the FA(faractional anisotropy) and ADC(apparent diffusion coefficient) values, which were derived from diffusion tensor imaging in breast cancer patients. The diffusion gradient used in this study was derived from quantitative diffusion indices using 20 directions(b-value, 0 and $1,000s/mm^2$). Quantitative analysis was analyzed using Pearson's correction and qualitative analysis using for correction coefficients. As a result, $FA_{min}$, $FA_{mean}$ and $FA_{max}$ were $0.098{\pm}0.065$, $0.302{\pm}0.142$ and $0.634{\pm}0.236$, respectively(p > 0.05). The $ADC_{min}$, $ADC_{mean}$ and $ADC_{max}$ were $0.741{\pm}0.403$, $1.095{\pm}0.394$ and $1.530{\pm}0.447$, respectively(p > 0.05). The $FA_{min}$, $FA_{mean}$, and $FA_{max}$ mean values were $0.132{\pm}0.050$, $0.418{\pm}0.094$, and $0.770{\pm}0.164$ for Category 6 and Kinetic Curve Pattern III, respectively. $ADC_{min}$, $ADC_{mean}$, and $ADC_{max}$ were $0.753{\pm}0.189$, $1.120{\pm}0.236$, and $1.615{\pm}0.372$, respectively. Quantitative analysis showed negative correlation between $ADC_{mean}-FA_{mean}$ and $ADC_{max}-FA_{max}$(p = 0.001, 0.003). The qalitative analysis showed ADC 0.628(p = 0.001), FA 0.620(p = 0.001) in the internal evaluations, ADC 0.677(p = 0.001), FA 0.695(p = 0.001) in external evaluations. In conclusion, based on the morphological examination, time to signal intensity graph is the form of wash-out(pattern III) in the dynamic contrast enhance examination, As a result, the $ADC_{mean}$ $1.120{\pm}0.236$ and $FA_{mean}$ values were $0.032{\pm}0.142$ with a negative correlation (Y=1.44-1.12X). Therefore, If we understand the shape of time to signal intensity graph and the relationship between ADC and FA, It will be a criterion for distinguishing malignant diseases in breast cancer.

A New Attempt to Establish the Extrinsic Aging Hair Model to Evaluate The Response to Aging in Physical Property (모발 노화에 따른 물성변화와 외인성 노화모델의 개발)

  • Song, Sang-Hun;Choi, Wonkyung;Park, Hyunsub;Lim, Byung Tack;Park, Kyoung Ran;Kim, Younghyun;Park, Sujin;Son, Seong Kil;Lee, Sang-Min;Kang, Nae-Gyu
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.45 no.2
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    • pp.185-198
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    • 2019
  • Human tissue undergoes aging by the oxidant damage via structural change and its physical properties. The skin aging process is well known and many evaluations have been conducted. However, studies on hair aging were relatively few and thus care for aging hair is difficult. This study aims to fabricate an aging hair and identify anti-aging effect with known ingredient in anti-aging. First of all, physical properties of aging hair of age 60s by physiologically intrinsic factors were compared to those of the hair made by various extrinsic factors such as several chemical reactions and iteration numbers of the treatments. The extrinsic aging hair of this study relates to the less amount of lipid and to the hair of perm treated once accordingly, wherein several physical properties, preferably comprise roughness and tensile strength, present a novel concept of the intrinsic aging hair. The penetration of peptide into the aging hair was leading the extrinsic hair towards more structurally directed a younger hair. In addition to the structural change, the penetration of the peptide enhanced texture and tensile strength of the aging hair. These patterns have been also found in addition of propolis. For the first time, these qualitative studies exhibit that indeed our extrinsic aging hair well describes the anti-aging efficacy as a receptor for a cross-linker and the ingredients of human hair.

Research Trends in Science Gifted Education from 2011 to 2015: Literature Analysis vs Social Network Analysis (2010년부터 2015년까지 국내 과학영재교육의 연구동향 분석 : 문헌분석 대 사회네트워크분석)

  • Yoon, Jin A;Seo, Hae-Ae
    • Journal of Science Education
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    • v.40 no.3
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    • pp.267-286
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    • 2016
  • The study aimed to investigate a research trend in science gifted education of six years from 2010 to 2015 by utilizing literature analysis and Social Network Analysis (SNA) methods. In this study, 275 papers published in eight major academic journals of science education and gifted education were selected as research subjects. First, through the literature analysis, it was found that the most frequent research topics were cognitive characteristics (25.8%), curriculum/programs (22.6%), and social and emotional characteristics (20.2%). For the research method employed in research papers, the survey research (46.5%) was appeared as the most frequently employed method, and followed by experimental (18.8%), program development (10.6%), correlation (10.3%), and qualitative (6.4%) research methods. The most frequent research subject was appeared as middle school students (33.7%) and followed by elementary school (30.6%), and high school (12.7%) students. Second, the SNA method was utilized for producing keyword frequency, degree centrality and network analyses. It was appeared that the most common keywords over six years included 'science gifted', 'gifted education', and 'creativity' and frequent keywords were science gifted, gifted education, gifted, creativity, science inquiry, perception, (creative) problem solving, science high school, scientific attitude, and STEAM. Third, through 2-mode network analysis, it was found that the research papers about cognitive characteristics were mainly related to perceptions, thinking ability, scientific argumentation, science inquiry and so on. It was also found that the research papers about social and emotional characteristics were related to correlation, motivation, creativity-character, self-efficiency and so on. It was concluded that the SNA method can be performed with literature analysis together for better understandings and interpretations of the research trend of science gifted education in-depth.

A Study on Measures to Create Local Webtoon Ecosystem (지역웹툰 생태계 조성을 위한 방안 연구)

  • Choi, Sung-chun;Yoon, Ki-heon
    • Cartoon and Animation Studies
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    • pp.181-201
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    • 2018
  • The cartoon industry in Korea has continued to decline due to the contraction of published comics market and decrease in the number of comic books rental stores until the 2000s when it rapidly started to experience qualitative changes and quantitative growth due to the emergence of webtoon. The market size of webtoon industry, valued at 420 billion won in 2015, is expected to grow to 880.5 billion won by 2018. Notably, most cartoonists who draw cartoon strips are using digital devices and producing scripts in data, thereby overcoming the geographical, spatial and physical limitation of contents. As a result, a favorable environment for the creation of local ecosystems is generated. While the infrastructures of human resources are steadily growing by region, cartoon industries that are supported by the government policy have shown good performance combined with factors of creative infrastructures in local areas such as webtoon experience centers, webtoon campuses and webtoon creation centers, etc. Nevertheless, it is true that cartoon infrastructures are substantially based on a capital area which leads to an imbalanced structure of cartoon industry. To see the statistics, companies of offline cartoon business in Seoul and Gyeonggi Province make up 87%, except for distribution industry. In addition, companies of online cartoon business which are situated outside of Seoul and Gyeonggi Province form merely 7.5%. Studies and research on local webtoon are inadequate. The existing studies on local webtoon usually focus on its industrial and economic values, mentioning the word "local" only sometimes. Therefore, this study looked into the current status of local webtoon of the present time for the current state of local cartoon ecosystem, middle and long-term support from the government, and an alternative in the future. Main challenges include the expansion of opportunities to enjoy cartoon cultures, the independence of cartoon infrastructure, and the settlement of regionally specialized cartoon cultures. It means that, in order to enable the cartoon ecosystem to settle down in local areas, it is vital to utilize and link basic infrastructures. Furthermore, it is necessary to consider independence and autonomy beyond the limited support by the government. Finally, webtoon should be designated as a culture, which can be a new direction of the development of local webtoon. Furthermore, desirable models should be continuously researched and studied, which are suitable for each region and connect them with regional tourism, culture and art industry. It will allow the webtoon industry to soft land in the industry. Local webtoon, which is a growth engine of regions and main contents of the fourth industrial revolution, is expected to be a momentum for the decentralization of power and reindustrialization of regions.

A Study on the Current State and Effect of Entrepreneurship Education in Major Countries: Comparison of the 2016 Global Entrepreneurship Index (주요 국가의 기업가정신 교육 현황 및 효과 연구: 2016년 글로벌 기업가정신 지수의 비교)

  • Nam, Jungmin;Lee, Hwansoo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.12 no.6
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    • pp.111-122
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    • 2017
  • This study analyzes the current state of entrepreneurship education and start-up foundations by country in order to find ways to improve the domestic entrepreneurial environment and to promote the recognition of desirable entrepreneurship practices. It also investigates the relationship between entrepreneurship, entrepreneurial will, and the level of opportunity-based entrepreneurships, by using data from the 2016 Global Entrepreneurship Trend Report (GETR). First, the results show the urgent need for the expansion of entrepreneurship education in Korea. In the GETR category of 'experience of entrepreneurship education in elementary, middle and high schools', Korea was ranked very low (19th place), among the 20 countries. In the 'college' and 'lifelong entrepreneurship education' categories, it procured a mid-level ranking (15th). While entrepreneurship education for all ages is being promoted globally, entrepreneurship education for middle-aged individuals in Korea is relatively weak. This implies that the expansion of entrepreneurship education to lifelong education and education for employees and retirees is required. Second, the individual's entrepreneurial intention in Korea was 3.8 points, implying a mid-level ranking (15th), and it ranked the lowest in terms of opportunity-based entrepreneurship (20th). In comparison to China (4.55) and the United States (4.01), the entrepreneurial intention of Koreans was found to be low. The level of opportunity-driven entrepreneurship was also found to be very low, compared to China (4.35), Japan (4.04) and the United States (4.59). In general, the proportion of the level in opportunity-driven entrepreneurship, increases from the factor-driven and efficiency-driven, to the innovation-driven type. In Korea, the percentage of entrepreneurial ventures centered around involuntary entrepreneurship and small businesses is high. It is also interpreted that opportunity-based entrepreneurships are low in number because of this high proportion of involuntary start-up and small businesses. Last, the entrepreneurial intention in all types (factor-driven, efficiency-driven, and innovation-driven) was exceptionally high. It has been confirmed that exposure to all entrepreneurship education (elementary, junior high, university, and lifelong education) in innovation-driven countries, greatly increases entrepreneurial intention. In the case of Korea, which is an innovation-driven country, qualitative improvement based on quantitative expansion of entrepreneurship education is expected to be a major driving force for individuals' entrepreneurial intention to obtain a mid-level ranking (15th).

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Exploring the Factors Influencing on the Accuracy of Self-Reported Responses in Affective Assessment of Science (과학과 자기보고식 정의적 영역 평가의 정확성에 영향을 주는 요소 탐색)

  • Chung, Sue-Im;Shin, Donghee
    • Journal of The Korean Association For Science Education
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    • v.39 no.3
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    • pp.363-377
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    • 2019
  • This study reveals the aspects of subjectivity in the test results in a science-specific aspect when assessing science-related affective characteristic through self-report items. The science-specific response was defined as the response that appear due to student's recognition of nature or characteristics of science when his or her concepts or perceptions about science were attempted to measure. We have searched for cases where science-specific responses especially interfere with the measurement objective or accurate self-reports. The results of the error due to the science-specific factors were derived from the quantitative data of 649 students in the 1st and 2nd grade of high school and the qualitative data of 44 students interviewed. The perspective of science and the characteristics of science that students internalize from everyday life and science learning experiences interact with the items that form the test tool. As a result, it was found that there were obstacles to accurate self-report in three aspects: characteristics of science, personal science experience, and science in tool. In terms of the characteristic of science in relation to the essential aspect of science, students respond to items regardless of the measuring constructs, because of their views and perceived characteristics of science based on subjective recognition. The personal science experience factor representing the learner side consists of student's science motivation, interaction with science experience, and perception of science and life. Finally, from the instrumental point of view, science in tool leads to terminological confusion due to the uncertainty of science concepts and results in a distance from accurate self-report eventually. Implications from the results of the study are as follows: review of inclusion of science-specific factors, precaution to clarify the concept of measurement, check of science specificity factors at the development stage, and efforts to cross the boundaries between everyday science and school science.

Variability of Selected Phenotypic Characteristics & Bitter Sesquiterpene Lactones contnet in Lettuce (Lactuca sativa L.) Germplasm (상추 유전자원의 원산지, 형태 및 엽색별 Bitter Sesquiterpene Lactones의 변이)

  • Choi, Susanna;Assefa, Awraris Derbie;Lee, Jae-Eun;Sung, Jung-Sook;Hur, On-Sook;Ro, Na-Young;Lee, Ho-Sun;Lee, Sok-Young;Rhee, Ju-Hee
    • Journal of the Korean Society of International Agriculture
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    • v.30 no.3
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    • pp.205-211
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    • 2018
  • Lettuce (Lactuca sativa L.) is one of the most important leafy vegetables in the world due to its health related benefits. Bitter sesquiterpene lactones (BSLs) are crucial secondary metabolites of lettuce which are useful in many physiological activities, and also has been used to relieve pain. This study was conducted to appraise the variability of phenotypic characteristics and the total content of BSLs in fifty lettuce germplasm. The germplasm collections exhibited wide variation in both qualitative and quantitative characters. The average plant weight was 333.3 g with a range from 60.0 to 700.0 g and the lactucin content was varied from 3.4 (IT265031) to $448.6(IT300287)\;{\mu}g/g\;DW$ with an average concentration of $94.0{\mu}g/g\;DW$. Whereas lactucopicrin ranged from 6.8 (IT217859) to $2,714.9(Superseonpung)\;{\mu}g/g\;DW$ with an average concentration of $805.8{\mu}g/g\;DW$. Total BSLs content was ranged from 19.6 (IT217859) to $2,821.9(Superseonpung)\;{\mu}g/g\;DW$ with the average concentration of $899.8{\mu}g/g\;DW$. Significant ($p{\leq}0.05$) differences in lactucin, lactucopicrin and total BSLs content were found among the germplasm collections. Leafy type lettuce germplasm collections originated from South Korea revealed the highest average total BSLs content ($2,821.9{\mu}g/g\;DW$). Principal component analyses of lactucin and lactucopicrin generated based on leaf color and plant growth type yielded two principal components, PC1 and PC2, which accounted for 60.8 and 39.2 % of the total variance, respectively. Our study provides fundamental insights on phenotypic characteristics and the total content of lactucin and lactucopicrin of lettuce germplasm which may further help researchers and breeders to produce improved lettuce varieties.