• Title/Summary/Keyword: 탐색적 연구

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Separation of Reducing Sugars from Rape Stalk by Acid Hydrolysis and Fabrication of Fuel Pellets from its Residues (산가수분해한 유채대로부터 유리당의 분리 및 이의 잔사로부터 펠릿의 제조)

  • Yang, In;Ahn, Byoung Jun;Kim, Myeong-Yong;Oh, Sei Chang;Ahn, Sye Hee;Choi, In-Gyu;Kim, Yong-Hyun;Han, Gyu-Seong
    • Korean Journal of Plant Resources
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    • v.27 no.1
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    • pp.60-71
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    • 2014
  • This study was conducted to identify the potential of rape stalk as a raw material for biorefinery process of rape flower. At first, rape stalk (RS) was immersed in distilled water (DW), acetic acid (AA), oxalic acid (OA), sulfuric acid (SA) and sodium hydroxide (SH) solutions, and the content of reducing sugars liberated from immersed RS was analyzed. Glucose, xylose, arabinose and sucrose were detected varying with the immersion type. In particular, 1% AA-immersion of RS for 72 hr was the most effective conditions to liberate glucose from RS. Secondly, the RS residues were used for elementary analysis and fabrication of fuel pellets. In addition to the solution type, concentration of immersion solutions (0%, 1%, 2%) and immersion time (24, 72, 120 hr) were used as experimental factors. The contents of nitrogen, sulfur and chlorine reduced effectively through the immersion of RS in DW, AA and OA solutions. For properties of RS-based pellets, bulk density and higher heating value of RS-based pellets greatly increased with the immersion of RS, and the qualities were much higher than those of the A-grade pellet of the EN standards. Ash content decreased remarkably through the immersion of RS, and was satisfied with the A-grade pellet standard. Durability was negatively affected by the immersion of RS, and did not reached to B-grade of the EN standard. In conclusion, acid immersion of RS can be a pretreatment method for the production of fuel pellet and bioethanol, but use of the immersed RS for the production of high-quality pellets might be restricted due to low durability of immersed-RS pellets. Therefore, further studies, such as investigation of detailed immersion conditions, fabrication of mixed pellets with wooden materials and addition of binders, are needed to resolve the problems.

Apoptotic Effect of Pinosylvin at a High Concentration Regulated by c-Jun N-Terminal Kinase in Bovine Aortic Endothelial Cells (혈관내피세포에서 c-Jun N-terminal kinase에 의해 조절되는 세포사멸에 고농도의 피노실빈이 미치는 효과)

  • Song, Jina;Park, Jinsun;Jeong, Eunsil;So, A-Young;Pyee, Jaeho;Park, Heonyong
    • Journal of Life Science
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    • v.25 no.4
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    • pp.416-424
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    • 2015
  • Pinosylvin is a stilbenoid found in the Pinus species. Pinosylvin at ~pM to ~nM concentrations induces cell proliferation, cell migration and anti-inflammatory activity in endothelial cells. However, it was recently reported that pinosylvin at high concentrations (50 to 100 μM) induces cell death in bovine aortic endothelial cells. In this study, we conducted a series of experiments to discover how pinosylvin at a high concentration (50 μM) induces endothelial cell death. Pinosylvin at the high concentration was shown to induce endothelial cell apoptosis through enhancing caspase-3 activity, flip-flop of phosphatidyl serine, and nuclear fragmentation. We found that pinosylvin at the high concentration additively increased caspase-3 activity enhanced by serum-starvation or treatment with 100 μM etoposide. We also determined that pinosylvin at the high concentration promoted activations of c-Jun N-terminal kinase (JNK) and endothelial nitric oxide synthetase (eNOS). We further ran a series of experiments to find out which signaling molecule plays a critical role in the pinosylvin-induced apoptosis. We finally found that SP-600125, a JNK inhibitor, had an inhibitory effect on the pinosylvin-induced endothelial cell death, but L-NAME, an eNOS inhibitor, had no effect. These data indicate that JNK is involved in the pinosylvin-induced apoptosis. Collectively, pinosylvin at high doses induces cell apoptosis via JNK activation.

Apoptotic Cell Death by Pectenotoxin-2 in p53-Deficient Human Hepatocellular Carcinoma Cells (종양억제유전자 p53 결손 인체간암세포에서 Pectenotoxin-2에 의한 Apoptosis 유도)

  • Shin, Dong-Yeok;Kim, Gi-Young;Choi, Byung-Tae;Kang, Ho-Sung;Jung, Jee-H.;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.17 no.10
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    • pp.1447-1451
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    • 2007
  • Through the screening of marine natural compounds that inhibit cancer cell proliferation, we previously reported that pectenotoxin-2 (PTX-2) isolated from marine sponges exhibits selective cytotoxicity against several cell lines in p53-deficient tumor cells compared to those with functional p53. However, the molecular mechanisms of its anti-proliferative action on malignant cell growth are not completely known. To further explore the mechanisms of its anti-cancer activity and to test whether the status of p53 in liver cancer cells correlates with their chemo-sensitivities to PTX-2, we used two well-known hepatocarcinoma cell lines, p53-deficient Hep3B and p53-wild type HepG2. We have demonstrated that PTX-2 markedly inhibits Hep3B cell growth and induces apoptosis whereas HepG2 cells are much more resistant to PTX-2 suggesting that PTX-2 seems to act by p53-independent cytotoxic mechanism. The apoptosis induced by PTX-2 in Hep3B cells was associated with the modulation of DNA fragmentation factor (DFF) family proteins, up-regulation of pro-apoptotic Bcl-2 family members such as Bax and Bcl-xS and activation of caspases (caspase-3, -8 and -9). Blockade of the caspase-3 activity by caspase-3 inhibitor, z-DEVD-fmk, prevented the PTX-2-induced growth inhibition in Hep3B cells. Moreover, treatment with PTX-2 also induced phosphorylation of AKT and extracellular-signal regulating kinase (ERK), but not c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MARK). Specific inhibitors of PI3K inhibitor (LY294002) and ERK1/2 inhibitor (PD98059) significantly blocks PTX-2-induced-anti-proliferative effects, whereas a JNK inhibitor (SP600125) and a p38 MAPK inhibitor (SB203580) have no significant effects demonstrating that the pro-apoptotic effect of PTX-2 mediated through activation of AKT and ERK signal pathway in Hep3B cells.

Exploring Ways to Improve the Predictability of Flowering Time and Potential Yield of Soybean in the Crop Model Simulation (작물모형의 생물계절 및 잠재수량 예측력 개선 방법 탐색: I. 유전 모수 정보 향상으로 콩의 개화시기 및 잠재수량 예측력 향상이 가능한가?)

  • Chung, Uran;Shin, Pyeong;Seo, Myung-Chul
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.19 no.4
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    • pp.203-214
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    • 2017
  • There are two references of genetic information in Korean soybean cultivar. This study suggested that the new seven genetic information to supplement the uncertainty on prediction of potential yield of two references in soybean, and assessed the availability of two references and seven genetic information for future research. We carried out evaluate the prediction on flowering time and potential yield of the two references of genetic parameters and the new seven genetic parameters (New1~New7); the new seven genetic parameters were calibrated in Jinju, Suwon, Chuncheon during 2003-2006. As a result, in the individual and regional combination genetic parameters, the statistical indicators of the genetic parameters of the each site or the genetic parameters of the participating stations showed improved results, but did not significant. In Daegu, Miryang, and Jeonju, the predictability on flowering time of genetic parameters of New7 was not improved than that of two references. However, the genetic parameters of New7 showed improvement of predictability on potential yield. No predictability on flowering time of genetic parameters of two references as having the coefficient of determination ($R^2$) on flowering time respectively, at 0.00 and 0.01, but the predictability of genetic parameter of New7 was improved as $R^2$ on flowering time of New7 was 0.31 in Miryang. On the other hand, $R^2$ on potential yield of genetic parameters of two references were respectively 0.66 and 0.41, but no predictability on potential yield of genetic parameter of New7 as $R^2$ of New7 showed 0.00 in Jeonju. However, it is expected that the regional combination genetic parameters with the good evaluation can be utilized to predict the flowering timing and potential yields of other regions. Although it is necessary to analyze further whether or not the input data is uncertain.

Research on the influence of web celebrity live broadcast on consumer's purchase intention - Adjusting effect of web celebrity live broadcast contextualization

  • Zou, Ji-Kai;Guo, Han-Wen;Liu, Zi-Yang
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.6
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    • pp.239-250
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    • 2020
  • The purpose of this paper is to explore the influence of the "contextualization" effect of web celebrity live broadcast on the e-commerce platform on consumers' perception of product value, risk and purchase intention. Live in this paper, using Taobao shopping consumers as the research object, the survey method, questionnaire survey is adopted, the form through the questionnaire and distributed network, a live in order to further validation of web celebrity effect of contextualized actual influence on consumer purchase intention, questionnaire design the Likert scale, seven and recycling questionnaire analysis using the statistical software SPSS 23.0 and AMOS 22.0 after processing the data. After determining the reliability and validity of the questionnaire, the exploratory factor analysis was used to verify the hypothesis and calculate the actual adjustment degree of the "contextualization" effect of web celebrity live broadcasting on consumers' purchase intention. The research results of this paper are summarized as follows :(1) consumers' perceived value of products can significantly positively affect their purchase intention, while perceived risk has a significantly negative impact on their purchase intention; (2) consumers' trust and purchase intention to products are regulated by the "contextualization" of web celebrity live broadcast. Specifically, for web celebrity live broadcasting with good "contextualization" effect, the perceived value of consumer products has a positive impact on product trust, which is higher than that of web celebrity live broadcasting with poor "contextualization" effect. In terms of resolving consumers' perceived risks to products, web celebrity live broadcast with good "contextualization" effect is also significantly better than web celebrity live broadcast with poor "contextualization" effect. Based on empirical analysis, this paper concludes that web celebrity live broadcasting will become a new breakthrough for the sustainable growth of the e-commerce industry, and puts forward Suggestions on the e-commerce marketing mode and the transformation of web celebrity live broadcasting industry.

Analyzing Inquiry Activities and Exploring the Difficulties of Teaching Inquiry Activities Presented in Science Textbooks for Grades 5-6 (초등 5~6학년 과학 교과서에 제시된 탐구 활동 유형 분석 및 탐구 활동 지도의 어려움 탐색)

  • Chae, Dong-Hyun;Shin, Jung-Yun;Kim, Eun-Ae
    • Journal of the Korean Society of Earth Science Education
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    • v.15 no.2
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    • pp.213-223
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    • 2022
  • The purpose of this study is to identify the types of essential inquiry activities presented in elementary science textbooks for grades 5-6, and to find out what difficulties teachers have in the actual teaching process. To this end, the essential research activities presented in the textbook were analyzed into six types: experimentation/observation, investigation/discussion and presentation, data interpretation, discussion/discussion, simulation activity, and expression. In addition, 108 elementary school teachers were investigated for the suitability of inquiry activity achievement standards, suitability at the student's level, student interest, and difficulty in teaching instruction. To summarize the research results, the most frequently suggested type was the experiment/observation type, followed by simulation activity type and data interpretation type. It was analyzed that there was no discussion/discussion type in the 5th grade textbooks, and the 6th graders did not present research activities that correspond to the research/discussion/presentation type and the expression type in the textbook. In the results of teachers' responses to the suitability of achievement standards for inquiry activities presented in textbooks and the suitability of the student's level, 5th graders showed lower average scores than 6th graders, and showed similar average scores in student interest and instructional difficulty. Also, it was confirmed that improvement was required for a total of 17 inquiry activities. Specifically, teachers responded that they had difficulty in guiding inquiry activities when the experimental results did not appear as intended in the textbook, when students' interest in inquiry activities was low, and when students and teachers had low understanding of related science concepts. Teachers pointed out practical problems such as difficulties in long-term observation in astronomy-related units, and students in upper elementary school not actively participating in dynamic play activities.

Development of a water quality prediction model for mineral springs in the metropolitan area using machine learning (머신러닝을 활용한 수도권 약수터 수질 예측 모델 개발)

  • Yeong-Woo Lim;Ji-Yeon Eom;Kee-Young Kwahk
    • Journal of Intelligence and Information Systems
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    • v.29 no.1
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    • pp.307-325
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    • 2023
  • Due to the prolonged COVID-19 pandemic, the frequency of people who are tired of living indoors visiting nearby mountains and national parks to relieve depression and lethargy has exploded. There is a place where thousands of people who came out of nature stop walking and breathe and rest, that is the mineral spring. Even in mountains or national parks, there are about 600 mineral springs that can be found occasionally in neighboring parks or trails in the metropolitan area. However, due to irregular and manual water quality tests, people drink mineral water without knowing the test results in real time. Therefore, in this study, we intend to develop a model that can predict the quality of the spring water in real time by exploring the factors affecting the quality of the spring water and collecting data scattered in various places. After limiting the regions to Seoul and Gyeonggi-do due to the limitations of data collection, we obtained data on water quality tests from 2015 to 2020 for about 300 mineral springs in 18 cities where data management is well performed. A total of 10 factors were finally selected after two rounds of review among various factors that are considered to affect the suitability of the mineral spring water quality. Using AutoML, an automated machine learning technology that has recently been attracting attention, we derived the top 5 models based on prediction performance among about 20 machine learning methods. Among them, the catboost model has the highest performance with a prediction classification accuracy of 75.26%. In addition, as a result of examining the absolute influence of the variables used in the analysis through the SHAP method on the prediction, the most important factor was whether or not a water quality test was judged nonconforming in the previous water quality test. It was confirmed that the temperature on the day of the inspection and the altitude of the mineral spring had an influence on whether the water quality was unsuitable.

A Study on the Setting Process and Formational Characteristics of the Seonyu Eight Scenic in Gogunsan Islands (고군산 선유팔경(仙遊八景)의 설정과정과 집경(集景) 특성)

  • Jung, Woo-Jin;Hwang, Guk-Woong
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.37 no.4
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    • pp.32-50
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    • 2019
  • The present study examines the circumstances around the establishment of the Seonyu Eight Scenic Spots (仙遊八景) in Gogunsan Islands and the characteristics of the landscape of each viewing point. The study conclusions are as follows. First, since the scenic spots were first established in 1969, their content and sequences have been changed several times, and their names have also been changed to some extent. Until the 1970s, these scenic spots did not have official names for them and were often specified as 'Gogunsan Eight Scenic Spots', and excluded 'the Musan Twelve Peaks (巫山十二峰)'. In addition, viewing points of the eight scenic spots varied across periods. This suggests that, for the early form of Seonyu Eight Scenic Spots, the picturesque scenery of Gogunsan Islands, and Seonyudo Island in particular, was chosen, while eight scenic spots in its vicinity were regarded. Second, the Seonyu Eight Scenic Spots of the early 2000s, which has all eight scenic spots of now, follows the nomenclature of the traditional eight scenic spots by specifying the sequence number with a refined name in four syllables. Its first scenic spot was Mangju Waterfall (望主瀑布) and its eighth scenic spot was Seonyu Sunset (仙遊落照); currently, the first scenic spot is Seonyu Sunset and the second scenic spot is Mangju Waterfall. Such change in the sequence of viewing points resulted from differences in representative landscape resources between the periods. Third, the lack of structure and finesse due to continuous changes is directed related to the identity issue of the Seonyu Eight Scenic Spots. Above all, it is unclear by whom and when Seonyu Eight Scenic Spots was established, and there are clear traces of following the eight scenic spots in the neighboring areas such as Okgu (沃溝) and Impi (臨陂)'s Eight Scenic Spots. Moreover, it is evaluated to have an unrefined, incomplete structure due to the lack of clarity in the knowledge and information about viewing objects, when to view, and historical and cultural background. Fourth, the first scenic spot, Seonyu Sunset, has the image that dominates the entire Eight Scenic Spots. The temporary landscape, the sunset, became the best view because it was perceived as the entirety of the landscape created by the fusion of the beautiful natural elements of Seonyudo Island. Therefore, there is ample room for raising the value of other landscape resources of Gogunsan Islands by utilizing the existing perception of exploring the entire landscape of Seonyudo Island and Gogunsan Islands starting with Seonyu Sunset. This likely requires additional work to imbue each viewing point with identity and completion.

Allium hookeri Extract Improves Type 2 Diabetes Mellitus in C57BL/KSJ Db/db Obese Mouse via Regulation of Hepatic Lipogenesis and Glucose Metabolism (삼채 추출물의 인슐린 저항성 개선 효과 및 기전 탐색)

  • Kim, Ji-Soo;Heo, Jin-Sun;Choi, Jong-Won;Kim, Gun-Do;Sohn, Kie-Ho
    • Journal of Life Science
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    • v.25 no.10
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    • pp.1081-1090
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    • 2015
  • Diabetes has been one of major health risks in industrialized countries. Allium hookeri is a wild herb distributed in India and Myanmar. The root of the plant has been used as food and medicine in Southeast Asia. We investigated Allium hookeri extract improves type 2 diabetes mellitus in C57BL/KSJ db/db obese mouse. C57BL/KSJ db/db obese mouse arise out of Type 2 diabetes and we treated Allium hookeri methanol extract 400 mg/kg (AH 400), 800 mg/kg (AH 800), positive control group (thiazolidinedine;TZDs) were administered orally for 8weeks. AH treated group normalized lipid enzyme system (triglyceride, total cholesterol, HDL-cholesterol and LDL-cholesterol) and serum glucose, HbA1c and plasma insulin level. AH treated group recovered β-cell damage by hyperglycemia and fatty liver disease. AH treated group significantly up regulated expression of Peroxisome proliferator-activated receptor gamma (PPAR-γ), pyruvate dehydrogenase kinase4 (PDK4), Sterol regulatory element-binding protein 1c (SREBP 1) and fork head box O1 (FOX 01) proteins in C57BL/KSJ db/db obese mouse liver. And we found that AH treated group decreased hepatic malondialdehyde formation in C57BL/KSJ db/db obese mouse liver. These results indicate that Allium hookeri methanol extract might be a potential anti-diabetic agent and could be useful in the treatment of type 2 diabetes mellitus.

Assessment of modifiable lifestyle factors for obese children and adolescents through questionnaires (소아청소년 비만상담에서 설문지를 이용한 중재 가능한 행동요인 탐색)

  • Seo, Jeong Wan;Jung, Ji A;Park, Hye Sook;Ko, Jae Sung;Kim, Yong Joo;Kim, Jae Young;Ryoo, Eell;Bae, Sun Hwan;Sim, Jae Geon;Yang, Hye Ran;Choe, Byung Ho;Cho, Ky Young
    • Clinical and Experimental Pediatrics
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    • v.51 no.6
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    • pp.576-583
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    • 2008
  • Purpose : The identification of specific behaviors conducive to overeating or inactivity is the cornerstone of obesity management. The Committee on Nutrition of the Korean Pediatric Society developed parent and self-reporting questionnaires about eating behavior and physical activity in 2006. The aim of this study was to evaluate the usefulness of the questionnaires in assessing modifiable lifestyle factors related to obesity. Methods : A retrospective chart review was performed for 177 children (6-11 years old) and 134 adolescents (12-16 years old) from 10 hospitals between May 2006 and January 2007 who had completed parent or self-reporting questionnaires. Cases were divided into normal and overweight groups at or above the age-gender-specific 85th percentile based on 2007 Korean national growth charts. Results : Compared to children, the adolescents tended to have a significantly more sedentary lifestvle and inappropriate dietary behaviors significantly (P<.05). Overweight mothers were significantly associated with overweight children and adolescents (P<.05). Being overweight was significantly associated with a family history of adult diseases for children and adolescents (P<.05). Inappropriate eating behaviors (strong appetite, eating fast, eating until they were full, binge eating, favoring greasy foods) were associated with being overweight in children and adolescents. Sedentary activity such as TV viewing and using a computer were significantly associated with overweight in children and adolescents (P<.05). Conclusion : Intervention to modify obesity-related lifestyle factors is needed before adolescence. These questionnaires are useful in identifying modifiable lifestyle factors and in individual counseling for overweight children and adolescents in pediatric clinics.