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Analyzing the Characteristics of Pre-service Elementary School Teachers' Modeling and Epistemic Criteria with the Blackbox Simulation Program (블랙박스 시뮬레이션에 참여한 초등예비교사의 모형 구성의 특징과 인식적 기준)

  • Park, Jeongwoo;Lee, Sun-Kyung;Shim, Han Su;Lee, Gyeong-Geon;Shin, Myeong-Kyeong
    • Journal of The Korean Association For Science Education
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    • v.38 no.3
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    • pp.305-317
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    • 2018
  • In this study, we investigated the characteristics of participant students' modeling with the blackbox simulation program and epistemic criteria. For this research, we developed a blackbox simulation program, which is an ill-structured problem situation reflecting the scientific practice. This simulation program is applied in the activities. 23 groups, 89 second year students of an education college participated in this activity. They visualized, modeled, modified, and evaluated their thoughts on internal structure in the blackbox. All of students' activities were recorded and analyzed. As a result, the students' models in blackbox activities were categorized into four types considering their form and function. Model evaluation occurred in group model selection. Epistemic criteria such as empirical coherence, comprehensiveness, analogy, simplicity, and implementation were adapted in model evaluation. The educational implications discussed above are as follows: First, the blackbox simulation activities in which the students participated in this study have educational implications in that they provide a context in which the nature of scientific practice can be experienced explicitly and implicitly by constructing and testing models. Second, from the beginning of the activity, epistemic criteria such as empirical coherence, comprehensiveness, analogy, simplicity, and implementation were not strictly adapted and dynamically flexibly adapted according to the context. Third, the study of epistemic criteria in various contexts as well as in the context of this study will broaden the horizon of understanding the nature of scientific practice. Simulation activity, which is the context of this study, can lead to research related to computational thinking that will be more important in future society. We expect to be able to lead more discussions by furthering this study by elaborating and systematizing its context and method.

Comparison of Antioxidant Activities of Radish Bud (Raphanus sativus L.) According to Extraction Solvents and Sprouting Period (추출용매 및 발아시기에 따른 무순 추출물의 항산화 활성 비교)

  • Han, Jin-Hee;Moon, Hye-Kyung;Chung, Shin-Kyo;Kang, Woo-Won
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.11
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    • pp.1767-1775
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    • 2013
  • The purpose of this study is to investigate the total polyphenol and antioxidant activities of radish buds (Raphanus sativus L.) based on sprouting periods and extraction solvents in order to present basic data that are needed for using the radish buds as functional food material. The antioxidant activities were assessed by using various antioxidant models (DPPH, TBARS, Rancimat method, POV). The total polyphenol contents according to the extraction solvents were 84.11 and 296.51 mg/g, and the ethanol extract on day 4 of showed the highest value as 296.51 mg/g. As for DPPH radical-scavenging activity, on the day 4 of sprouting, water extracts indicated the highest scavenging activity by 86.67%, and the acetone extracts indicated a rather low scavenging activity as 77.23%. As for TBARS measurement of the radish bud extracts on day 4 of sprouting the extract of 70% ethanol was highest (71.48%). On day 8 of sprouting the TBARS value was increased and the methanol extract was highest (78.99%). As for the oxidative induction period on day 4 of sprouting in Rancimat measurement, the methanol extract was highest (6.07 hours) on day 4 and the antioxidant index was 1.16. On day 12 of sprouting, the general oxidative induction period tended to be reduced to 5.25 to 5.91 hours. In the peroxide value measurement on day 4 of sprouting and beginning of the storage, the extracts showed no difference between 3.02 meq/kg oil and 4.12 meq/kg oil, and on the day 60 of storage, the water extract (43.83 meq/kg oil) and the methanol extract (45.42 meq/kg oil) were lowest with higher antioxidant effect. In conclusion, the radish bud extract with higher total polyphenol contents and antioxidant activities may serve as functional material for food additives, such as natural antioxidants and food preserving agents.

Enhancement of Antioxidant Activities of Codonopsis lanceolata and Fermented Codonopsis lanceolata by Ultra High Pressure Extraction (초고압 추출 처리에 의한 더덕 및 발효더덕의 항산화 증진)

  • Park, Sung-Jin;Park, Dong-Sik;Lee, Su-Bock;He, Xin-Long;Ahn, Ju-Hee;Yoon, Won-Byung;Lee, Hyeon-Yong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.12
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    • pp.1898-1902
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    • 2010
  • This study was designed to evaluate antioxidant activity of low-quality Codonopsis lanceolata treated by fermentation process followed by hydraulic high pressure extraction. C. lanceolata was subjected to 5,000 bar for 30 min at $25^{\circ}C$. The highest phenolics content was observed in the combined treatment of fermentation and high pressure extraction (35.11 mg/100 g), followed by high pressure extraction alone (14.78 mg/100 g) and conventional extraction (14.56 mg/100 g). The content of flavonoids followed the similar pattern as that of total phenolics, showing 280.86 mg/100 g of C. lanceolata treated by the combined fermentation with high pressure extraction whereas 193.05 mg/100 g of C. lanceolata treated by the conventional extraction. The DPPH scavenging activity was 69.32% at 0.6 mg/mL of C. lanceolata treated by the combined process, while the DPPH scavenging activities of C. lanceolata treated by high pressure extraction alone and the conventional extraction were 60.35% and 30.92%, respectively. The highest reducing power of C. lanceolata extract (1.0 mg/mL) was observed at the combined treatment (0.926), followed by high pressure extraction alone (0.881) and the conventional extraction (0.733). The combination of fermentation with high pressure extraction significantly increased the contents of phenolics and flavonoids and also enhanced the antioxidant activity. Therefore, the combined application of fermentation and high pressure extraction can be an alternative technique for the extraction of C. lanceolata. These results provide useful information for enhancing biological properties of low-quality C. lanceolata.

Biological Activities in the Extract of Fermented Codonopsis lanceolata (발효더덕 추출물의 생리활성)

  • Park, Sung-Jin;Song, Seong-Won;Seong, Dong-Ho;Park, Dong-Sik;Kim, Seung-Seop;Gou, Jinyu;Ahn, Ju-Hee;Yoon, Won-Byung;Lee, Hyeon-Yong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.8
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    • pp.983-988
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    • 2009
  • To investigate the applicability of hot water extract from Codonoposis lanceolata (CL) and fermented Codonoposis lanceolata (FCL) as functional food and cosmeceutical material, its total phenolic contents, total flavonoids, electron donating ability (EDA), SOD-like activity, nitrate-scavenging ability (NSA), reducing power were examined. Total phenolic contents of CL and FCL were 0.54 mg/100 g and 2.79 mg/100 g, respectively, and total flavonoids contents were estimated as 2.26 mg/100 g for CL and 6.16 mg/100 g FCL. The EDA of CL and FCL were 8.0$\sim$17.9% and 32.9$\sim$74.9%. The SOD-like activities of CL and FCL were 0.6$\sim$16.5% and 3.5$\sim$21.6%, respectively, and the activity was dependent on the sample concentration. The NSA was pH dependent, and was the highest at pH 1.2 and the lowest at pH 6.0. The NSA of FCL was higher than that of CL. The FCL extract showed the highest reducing power (0.65) at the concentration of 1,000 $\mu g$/mL. Based on the above results, we deemed that the FCL might have potential antioxdant activities.

Component Analysis and Antioxidant Activity of Oenanthe javanica Extracts (돌미나리 추출물의 함유성분 분석과 항산화 활성)

  • Hwang, Seok-Jun;Park, Sung-Jin;Kim, Jong-Dai
    • Korean Journal of Food Science and Technology
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    • v.45 no.2
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    • pp.227-234
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    • 2013
  • The purpose of this study was to determine the possibility of using Oenanthe javanica as a natural health food source. To accomplish this, its general and biological activities were measured. Its carbohydrate, crude protein, crude lipid, and ash contents were 44.7, 9.8, 8.9, and 27.8%, respectively. The K content was largest for minerals followed by Ca, P, and Mg, which means that Oenanthe javanica is an alkali material. The concentrations of total phenol and flavonoids of OJE were $88.9{\pm}0.46$ mg GAE/g, and $28.6{\pm}0.64$ mg QE/g, respectively. Gallic acid, catechin, chlorogenic acid, and caffeic acid in OJE as measured by using HPLC were $0.9{\pm}0.23$, $1.2{\pm}0.19$, $227.1{\pm}0.62$, and $4.0{\pm}0.35$ mg/g. The DPPH and ABTS radical scavenging activities of OJE were 72.2%, and 66.1%, respectively, at $1,000{\mu}g/mL$. The FRAP and reducing power of OJE were 0.79, and 0.41 absorbance units value respectively, at $1,000{\mu}g/mL$. OJE possessed significant antioxidant properties, which suggests its great potential as a functional ingredient for food applications.

Effects of Zizyphus jujuba var. boeunesis Extracts on the Growth of Intestinal Microflora and Its Antioxidant Activities (대추 추출물이 장내 미생물의 생육에 미치는 영향 및 항산화 활성)

  • Jeong, Hye-Mi;Kim, Yi-Seul;Ahn, Seung-Joon;Auh, Mi-Sun;Ahn, Jun-Bae;Kim, Kwang-Yup
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.4
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    • pp.500-508
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    • 2011
  • This study was carried out to investigate the effects of jujube extracts on intestinal microflora, along with their antioxidant activities, according to extraction method. The antimicrobial activities of the extracts were measured using the agar diffusion method with a jujube extract concentration of 50 mg/mL. Neither the first nor second jujube extracts were inhibitory against the tested intestinal bacteria. However, water extracts of jujube significantly enhanced the growth of lactic acid bacteria, especially Bifidobacterium bifidum and Bifidobacterium adolescentis. Total phenol compounds and flavonoid compounds were higher in the 1st than in the 2nd water extracts. The EDA values of both water and ethanol extracts increased in proportion to the extract concentration. The 1st water extract showed the highest value among all the others, which was 85.60% at the concentration of 0.05 mg/mL. Furthermore, the 1st water extract showed stronger antioxidant activity than the other samples with an activity of 679.91 mg AA eq/g. These results support the potential use of jujube water extracts as a functional food component and a valuable resource for the development of nutraceutical foods, to increase the growth of Bifidobacterium spp. in the human intestine.

Effect of extract temperature and duration on antioxidant activity and sensory characteristics of Ulmus pumila bark extract (추출온도 및 시간에 따른 유백피 추출물의 항산화 활성과 음료의 관능적 특성)

  • Cho, Myoung Lae;Oh, Yu-Na;Ma, Jin-Gyeong;Lee, Su-Jin;Choi, Young-Hee;Son, Dong-Hwa;Jang, Eun Hee;Kim, Jong-Yea
    • Food Science and Preservation
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    • v.23 no.7
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    • pp.995-1003
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    • 2016
  • Ulmus pumila L. bark underwent distilled water extraction under three temperature condition ($4^{\circ}C$, room temperature, or $80^{\circ}C$) and two extraction times (1, or 5 min) in order to develop a functional beverage products. Changes in yield, pH, color, total phenolic (TP) content, tannin content and antioxidant activity of the aqueous extracts were evaluated for each extraction temperature and duration. Extraction conditions did not affect yield or pH value of the extracts; however CIE $b^*$ values were high in extracts prepared under high extraction temperature ($80^{\circ}C$) and long extraction duration (5 min) conditions. Both extraction temperature and duration affected the TP and tannin contents of the extracts; however, all extraction conditions resulted in ${\geq}450\;mg\;GAE/g$ TP content and ${\geq}80\;mg\;CE/g$ tannin content. All extracts exhibited ABTS and DPPH radical scavenging ability similar to that of vitamin C. Nitric oxide inhibition activity was lower in the 5 min duration sample than in the 1 min sample. The $4^{\circ}C$ extraction temperature produced an extract with the highest reducing power and hydrogen peroxide values. Extraction temperature also affected sensory evaluation results with the $80^{\circ}C$ extraction temperature producing significantly higher flavor, bitterness, and color score, than those obtained under $4^{\circ}C$ and room temperature extraction conditions.

Functional Properties of Water Extracts from Different Parts of Acanthopanax sessiliflorus (오가피 부위별 열수 추출액의 기능적 특성)

  • Choi, Jae-Myoung;Kim, Kwang-Yup;Lee, Sang-Hwa;Ahn, Jun-Bae
    • Food Engineering Progress
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    • v.15 no.2
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    • pp.130-135
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    • 2011
  • Acanthopanax sessiliflorus (A. sessiliflorus) has been known as a traditional medicine having anti-stress, antioxidative and platelet aggregation inhibitory effects. This study was undertaken to investigate the functional properties of water extracts from four parts of A. sessiliflorus. Root, stem, leaf and fruit extracts from A. sessiliflorus were prepared with hot water ($80^{\circ}C$). The contents of functional substances, eleutheroside B and E, polyphenol, antioxidative activity, nitrite scavenging ability and anti-cancer activity of the extracts were determined. The contents of eleutheroside E in stem, root and fruit extracts were 542.50 ${\mu}$g/g, 343.35 ${\mu}$g/g and 30.78 ${\mu}$g/g, respectively. A large part of eleutheroside B was found in fruit (372.01 ${\mu}$g/g) and root (289.33 ${\mu}$g/g) extracts. Root and stem extracts contained 227.21 mg/100g and 131.22 mg/100g of polyphenols, respectively. Antioxidative activities (electron donating ability) of stem and root extracts were 79.87% and 77.27%, respectively. It appears that the antioxidative activities were related to polyphenol contents of the extracts. Most extracts showed 76-81.5% of nitrite scavenging ability at pH 1.2. It reveals that water extract from parts of A. sessiliflorus can inhibit formation of nitrosoamine in food. Effects of the extracts on the growth of normal and cancer cell lines were investigated. Extracts showed no cytotoxicity to normal dendritic cell line (DC2.4). Especially, the root extract promoted the growth of normal cell line. Root and stem extracts had 20-23% of inhibitory effect against stomach cancer cell line (SNU-719) and liver cancer cell line (Hep3B). These result indicated that the extracts from A. sessiliflorus can be used as functional food materials with antioxidative activity and nitrite scavenging ability to eliminate nitrosoamine in food.

Comparison of Property Changes of Black Jujube and Zizyphus jujube Extracts during Lactic Acid Fermentation (흑대추와 일반 건조대추의 추출 및 유산발효과정 중 특성 변화)

  • Auh, Mi Sun;Kim, Yi Seul;Ahn, Seung Joon;Ahn, Jun Bae;Kim, Kwang Yup
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.10
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    • pp.1346-1355
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    • 2012
  • This study was carried out to investigate the characteristics of black jujube and Zizyphus jujube extracts during lactic acid fermentation. Both extracts were fermented using Lactobacillus fermentum YL-3. As a result, viable cell number rapidly increased until 24 hours, after which it gradually decreased. Before lactic acid fermentation, the $IC_{50}$ of black jujube, which was 0.014 mg/mL, was lower than that of Zizyphus jujube. Further, black jujube showed stronger antioxidant activity (374.21 mg AA eq/g) than Zizyphus jujube. Contents of total polyphenolics in both extracts were 15.46 mg/g and 13.61 mg/g, respectively, whereas contents of total flavonoids were 374.21 ${\mu}g/g$ and 64.25 ${\mu}g/g$. After lactic acid fermentation, there was no significant increase in DPPH or ABTS free radical scavenging activity. Total polyphenolic content of Zizyphus jujube decreased to 12.39 mg/g upon fermentation, whereas flavonoid content significantly increased to 291.58 ${\mu}g/g$. Further, polyphenolic and flavonoid contents of black jujube increased from 15.46 mg/g to 17.46 mg/g and from 374.21 ${\mu}g/g$ to 1,135.29 ${\mu}g/g$, respectively. These results demonstrate that 9-Times Steamed and Dried increased functional components. Especially, lactic acid fermented black jujube showed remarkably high antioxidant activity. These results confirm the potential use of lactic acid fermented black jujube as a valuable resource for the development of functional foods.

Implementation Strategy for the Elderly Care Solution Based on Usage Log Analysis: Focusing on the Case of Hyodol Product (사용자 로그 분석에 기반한 노인 돌봄 솔루션 구축 전략: 효돌 제품의 사례를 중심으로)

  • Lee, Junsik;Yoo, In-Jin;Park, Do-Hyung
    • Journal of Intelligence and Information Systems
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    • v.25 no.3
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    • pp.117-140
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    • 2019
  • As the aging phenomenon accelerates and various social problems related to the elderly of the vulnerable are raised, the need for effective elderly care solutions to protect the health and safety of the elderly generation is growing. Recently, more and more people are using Smart Toys equipped with ICT technology for care for elderly. In particular, log data collected through smart toys is highly valuable to be used as a quantitative and objective indicator in areas such as policy-making and service planning. However, research related to smart toys is limited, such as the development of smart toys and the validation of smart toy effectiveness. In other words, there is a dearth of research to derive insights based on log data collected through smart toys and to use them for decision making. This study will analyze log data collected from smart toy and derive effective insights to improve the quality of life for elderly users. Specifically, the user profiling-based analysis and elicitation of a change in quality of life mechanism based on behavior were performed. First, in the user profiling analysis, two important dimensions of classifying the type of elderly group from five factors of elderly user's living management were derived: 'Routine Activities' and 'Work-out Activities'. Based on the dimensions derived, a hierarchical cluster analysis and K-Means clustering were performed to classify the entire elderly user into three groups. Through a profiling analysis, the demographic characteristics of each group of elderlies and the behavior of using smart toy were identified. Second, stepwise regression was performed in eliciting the mechanism of change in quality of life. The effects of interaction, content usage, and indoor activity have been identified on the improvement of depression and lifestyle for the elderly. In addition, it identified the role of user performance evaluation and satisfaction with smart toy as a parameter that mediated the relationship between usage behavior and quality of life change. Specific mechanisms are as follows. First, the interaction between smart toy and elderly was found to have an effect of improving the depression by mediating attitudes to smart toy. The 'Satisfaction toward Smart Toy,' a variable that affects the improvement of the elderly's depression, changes how users evaluate smart toy performance. At this time, it has been identified that it is the interaction with smart toy that has a positive effect on smart toy These results can be interpreted as an elderly with a desire to meet emotional stability interact actively with smart toy, and a positive assessment of smart toy, greatly appreciating the effectiveness of smart toy. Second, the content usage has been confirmed to have a direct effect on improving lifestyle without going through other variables. Elderly who use a lot of the content provided by smart toy have improved their lifestyle. However, this effect has occurred regardless of the attitude the user has toward smart toy. Third, log data show that a high degree of indoor activity improves both the lifestyle and depression of the elderly. The more indoor activity, the better the lifestyle of the elderly, and these effects occur regardless of the user's attitude toward smart toy. In addition, elderly with a high degree of indoor activity are satisfied with smart toys, which cause improvement in the elderly's depression. However, it can be interpreted that elderly who prefer outdoor activities than indoor activities, or those who are less active due to health problems, are hard to satisfied with smart toys, and are not able to get the effects of improving depression. In summary, based on the activities of the elderly, three groups of elderly were identified and the important characteristics of each type were identified. In addition, this study sought to identify the mechanism by which the behavior of the elderly on smart toy affects the lives of the actual elderly, and to derive user needs and insights.