• The Plant Pathology Journal
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• v.20 no.3
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• pp.184-191
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• 2004

Methanol extracts of fresh materials of 57 plants were screened for in vivo antifungal activity against Magna-porthe grisea, Corticium sasaki, Botrytis cinerea, Phyto-phthora infestans, Puccinia recondita, and Blumeria graminis f. sp. hordei. Among them, seven plant extracts showed disease-control efficacy of more than 90％ against at least one of six plant diseases. None of the plant extracts was highly active against tomato gray mold. The methanol extracts of Chloranthus japonicus (roots) (CjR) and Paulownia coreana (stems) (PcS) displayed the highest antifungal activity; the CjR extract controlled the development of rice blast, rice sheath blight, and wheat leaf rust more than 90％, and tomato gray mold and tomato late blight more than 80％. The PcS extract displayed control values of more than 90 ％ against rice blast, wheat leaf rust, and barley powdery mildew and more than 80％ against tomato gray mold. The extract of PcS also had a curative activity against rice sheath blight and that of CjR had a little curative activity against rice blast. On the other hand, the extract of Rumex acetocella roots reduced specifically the development of barley powdery mildew. Further studies on the characterization of antifungal substances in antifungal plant extracts are underway and their disease-control efficacy should be examined under greenhouse and field conditions.

• Journal of The Korean Association For Science Education
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• v.15 no.1
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• pp.116-125
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• 1995

This study is to consider hypotheses with integral view on the respect of creative thinking. Subjects of this study are Korean students in the 5th grade who participated in the Field Trip Contest of the second Korean Youth Science Festival, an openended inquiry investigation. Objectives of this study are as follows: 1) to measure the inquiry level of the Field Trip Contest activity 2) to find how many hypotheses were made on different types in the inquiry investigation 3) to measure the quality level of hypotheses made in the scientific inquiry investigation 4) to find out the correlation between the 1st and 2nd hypotheses and the final activity score in the two staged scientific investigation In the consequence of it, inquiry level of the Field Trip Contest was very high with good activity topics and openended way of investigation. Hypotheses were made in the prediction, plan, and conclusion parts in the field trip activity report. They used hypothesis-as-prediction typed statements(3.41/team) more than hypothesis-as-explanation(1.28/team) and descriptive hypothesis(0.03/team) types. Content-related hypothesis(5.03/team) and process-related hypothesis(6.16/team) were usually coupled each other. Most of them had difficulties in hypothesis-from-evidence(0.31/team, 10/32 teams) in the comparison of hypothesis-from-simple conjecture(10.62/team). The quality level of content-related hypotheses(0.74point/statement) and process-related hypotheses(1.98point/statement) were very low by the hypothesis-quality scale(Quinn and George, 1975) for the content-related hypotheses and the process-related hypothesis quality scale developed in this study. There was considerable correlation between the activity score and the 1st and 2nd hypothesis in the 2 staged inquiry investigations with the 2nd and 3rd topics($0.41{\ast}$, $0.59{\ast}{\ast}$ repectively).

• The Plant Pathology Journal
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• v.22 no.3
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• pp.289-294
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• 2006

Two isolates of mucous bacteria, mc75 and pc78, were isolated from fungal culture plate as culture contaminants with an interesting swarming motility. Both isolates were identified as Pseudomonas fluorescens based on microscopy, biochemical analysis, Biolog test and DNA sequence analysis of the 16S rRNA gene. Both strains have the exactly the same 16S rRNA gene sequences, and yet their biological control activity were not identical each other. In vitro analysis of antagonistic activity of two isolates against several plant pathogenic fungi indicated that both produced diffusible and volatile antifungal compounds of unknown identities. Treatment of the bacterial culture of P. fluorescens pc78 and its culture filtrate exhibited a strong biological control activity against rice sheath blight in vivo among six plant diseases tested. More effective disease control activity was obtained from treatment of bacterial culture than that of culture filtrate. Therefore, in addition to antifungal compound and siderophore production, other traits such as biofilm formation and swarming motility on plant surface may contribute to the biological control activity of P.fluorescens pc78 and mc75.

• The Korean Journal of Mycology
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• v.34 no.2
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• pp.84-87
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• 2006

In the present study, an attempt has been made to produce a high quality medicinal mushroom Cordycops militaris supplemented with organic Ge. Cordycops militaris was cultivated in SDAY liquid medium containing yeast extract 10 g, peptone 10 g, glucose 40 g per liter and chrysalis media supplemented with inorganic Ge at 100, 500, 1000, and 5000 ppm concentrations. The greatest organic Ge production of 442.4 ppm/g and 284 ppm/g were observed in SDAY liquid and Chrysalis media cultures supplemented with 100 ppm inorganic Ge respectively. Similarly, 4,509.7 ppm/g and 1,058 ppm/g of organic Ge were obtained from liquid and chrysalis media cultures supplemented with 5,000 ppm and 1,000 ppm inorganic Ge, respectively. In addition, higher concentration of organic Ge was obtained in mycelia than fruiting bodies. These results indicate that the concentration of organic Ge increase with decreasing inorganic Ge concentration in the medium. This is the first report on production of high valuable Cordyceps militaris contained with organic Ge.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.146-156
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• 2020

The purpose of this study was to verify the effect of team process and affect state on members' organizational commitment. To this end, a valid questionnaire was received from 241 employees working at a company, and the collected questionnaire analyzed the relationship through regression analysis. As a result, we found that all of the team process factors - the conversion process, the execution process, and the interpersonal process - had a meaningful positive effect on organizational commitment. The conversion process had a positive effect on positive-activity and positive-inactivity - which is the types of the members' affect state. The interpersonal process had a positive effect on positive-activity and positive-inactivity, and negative effect on negative-inactivity and negative-activity. And the positive-activity had an intermediation effect on the relationship between team process and organizational commitment. Through this study, the significance of this study can be found in that it suggested the importance of building and managing the team process in order to maximize the efficiency of human resource management in the organization and improve the team effectiveness.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.4
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• pp.1-11
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• 2017

Our society has changed from an industrial society to a knowledge - based society, and the need for new knowledge creation activities through the convergence of various knowledge is emphasized. In accordance with these changes, universities aiming at nurturing human resources for society have sought new approaches and changes. The discussion of various curriculum for the future talent training in the university is aimed at the goal of developing problem solving ability irrespective of the subject of education or major. In this study, we tried to show that computational thinking ability can be improved by strengthening creative team activities by combining design thinking method in computer curriculum of general education course of university. To do this, we conducted a design thinking team project for students of computer general education course at G university in Gyeongnam province and conducted a survey. The results of the questionnaire were verified by statistical methods. The variables of this study satisfied both the validity and the reliability. Multiple regression analysis showed that knowledge sharing, team activity satisfaction, and design thinking project satisfaction factors all affect computing thinking ability.

• Journal of Engineering Education Research
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• v.26 no.2
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• pp.45-53
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• 2023

This study conducted and evaluated the PBL-based team activity classes in contact and untact learning. Appropriate subject (Engineering communication) was also selected and evaluation methods were improved. In the qualitative evaluation results, in contact learning, similar score ranges were formed for each task, and the variability of scores for each task was not large. In untact learning, the difference in scores for each task was rather large, and the variability of scores for each task was large, indicating a large difference between teams that performed well and teams that did not. In the quantitative evaluation, contact learning showed a little low grades, but untact learning showed relatively high grades, but there were limitations in showing the conclusion that the untact learning effect was very good. As a result of the survey, there were more positive responses to the degree of understanding of the class conducted online, the degree of help to improve competence, and the team activity. However, if untact learning continues, it was analyzed that it is necessary to prepare appropriate measures to enhance learning effects and efficiently conduct team activities.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.19-25
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• 2013

This study focused on the usefulness of plant extracts for a city organic farm. Insecticidal activity of 8 plant species, plants crude extracts by ethanol and water, against third instar larvae (susceptible strain) of Plutella xylostella was evaluated in this study. Ethanol(25%) extracts of plant materials had better insecticidal activity than water extracts at the room temperature. Insecticidal activity were investigated by leaf disc spray method. Five plant extracts (Capsicum annuum, Chelidoniun majus, Leonurus sibiricus, Coptis japonica, Mentha piperascens) showed over 50% insecticidal activity to P. xylostella at the concentration of $1500mg{\cdot}L^{-1}$. Extract of C. annuum showed the highest insecticidal activity (83.3%) against P. xylostella. Phytotoxicity was not observed on Raphanus sativus and Brassica campestris with spray application. Seed germination and growth of two plants were not affected. Extract of C. japonica revealed 73.3% control efficacy against P. xylostella of R. sativus and showed 70% control efficacy against those of B. campestris, respectively, in plastic house. Insecticidal activity against various insects was observed in C. japonica extract as 87.4% for R. sativus and 74.3% for B. campestris in the field. These results suggested that extracts of C. annuum, C. japonica showed the highest insecticidal activity, and could be used as city farm insecticides for organic farming.

• Journal of Engineering Education Research
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• v.19 no.4
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• pp.14-23
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• 2016

This study is to analyze the team interaction in accordance with the team size. Thereby, it is to reveal the team size for the attainment of the effective team interaction and the specific goals to achieve the purpose of this study are as follows. Firstly, the frequency and percentage of team interaction in accordance with the team size are presented. Secondly, the statistical verification of the team interaction in the social emotional area is conducted. Thirdly, the statistical verification of the team interaction in the task area is conducted. In order to do this study, we explain the purpose of study, confidentiality, and withdrawal right were described and then 32 persons who agreed to participate were selected as the subjects for the study. After that, the autonomous organization of team was induced and a total of 8 teams were organized - 3 teams comprised of 3 members, 3 teams of 4 members, 1 team of 5 members, and 1 team of 6 members. Further, Bales' (1950) Interaction Process Analysis (IPA) was used in order to analyze the team interaction, and Mangold INTERACT was used as a coding program. The results of study are as follows. Firstly, the highest frequency of the team interaction showed up in the case of five or six members and the lowest in the case of 3 members. Secondly, a statistically significant difference in the social emotional (positive) area showed up in accordance with the team size and the team organizations of three or four members were effective. Thirdly, a statistically significant value in the answer area showed up in accordance with the team size and the team organizations of five or six members were effective.

• Toxicological Research
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• v.27 no.3
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• pp.181-184
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• 2011

Screening of estrogenic activity on dichloro diphenyl trichloroethane (DDT), dichloro diphenyl dichloro ethylene (DDE), dieldrin, heptachlor, aldrin, chlordane, lindane, polybrominated diphenyl ethers (PBDE) and parabens was compared using Organization for Economic Cooperation and Development (OECD) test guideline 455 (TG455). The estrogenic activity of DDT was 58,000-fold ($PC_{50}$, $1.67{\times}10^{-6}$ M) less than $17{\beta}$-estradiol($E_2$) ($PC_{50}$, $2.88{\times}10^{-11}$ M) but DDE, dieldrin, heptachlor, aldrin, chlordane, lindane and PBDE did not show any estrogenic activity in this assay system. In the case of paraben compounds, the rank of relative transcriptional activation (logRTA) was butyl paraben -1.63752 ($PC_{50}$, $1.25{\times}10^{-7}$ M) > isobutyl paraben -2.34008 ($PC_{50}$, $6.3{\times}10^{-7}$ M) > ethyl paraben -2.64016 ($PC_{50}$, $1.26{\times}10^{-6}$ M) > isopropyl paraben -2.73993 ($PC_{50}$, $1.58{\times}10^{-6}$ M) > propyl paraben -2.84164 ($PC_{50}$, $2.0{\times}10^{-6}$ M). Our data suggest that OECD test guideline TG455 may be useful as a screening tool for potential endocrine disruptors.