• 한국초등과학교육학회지:초등과학교육
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• 제28권4호
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• pp.507-518
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• 2009

The purpose of this study was to determine the effects of verbal analogy activities on science achievement and science attitude of elementary students. Students consolidated lessons by making short sentences with core words that a teacher gave for scaffolding instruction. Many researches about analogies have been conducted in science education. However, most of them considered analogy as learning tools, whereas this research considers analogy as a cognitive process. To see the effects of verbal analogy activities, two groups were selected from 6th grade elementary school students; one was an experimental group working with the student-generated verbal analogy and the other was a control group with teacher-centered and textbook-centered activities. Science achievement, scientific attitudes, attitudes toward science and retention were tested after the treated lessons.

• 원예과학기술지
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• 제34권6호
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• pp.940-958
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• 2016

The objective of this study was to analyze the kinematic and kinetic characteristics of two horticultural activities: seed sowing and planting plant. Thirty-one male university students (aged $26.2{\pm}2.0years$) participated in this study. Kinematic factors (movement times, peak velocity, joint angles, and grasp patterns) were assessed using a three-dimensional motion analysis system while the subjects performed the horticultural activities. Kinetic factors (muscle activation of eight upper-limb muscles: the anterior deltoid, serratus anterior, upper trapezius, infraspinatus, latissimus dorsi, biceps brachii, brachioradialis, and flexor carpi radialis) were assessed using surface electromyography. The acts of seed sowing and planting plant were comprised of five tasks which included six types of phases: reaching, grasping, back transporting, forward transporting, watering, and releasing. The movement times, peak velocity, joint angles, and grasp patterns were significantly different across the tasks involved in the horticultural activities. All eight muscles of the upper limbs were utilized during the horticultural activities, and the muscle activation of the serratus anterior was the highest compared to that of the other muscles tested. The kinematic and kinetic characteristics of these horticultural activities showed similar characteristics to reaching and grasping rehabilitation training and daily living activities. The present study provides reference data for common horticultural activities using a kinematic and kinetic analysis.

• 한국약용작물학회지
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• 제12권2호
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• pp.141-148
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• 2004

Two compounds from Gomisin N and Gomisin A were isolated from the fruits of Schizandra chinensis Baillon. The highest extraction yield as 21.36% was observed in the ethanol extract, compared to the yield obtained form the water extract. The extraction yields of the single compounds were measured to be 0.13 and 0.014 Gomisin A and Gomisin N, respectively. Approximately, 90% of the growth of human stomach adenocarcinoma cancer cells was inhibited after adding 1.0 g/l of the ethanol extract. The growth of the human normal lung cell was limited to 24% after adding the ethanol extract. The water extract lowered the specific secretion of $TNF-\acute{a}$ and IL-6 from T cells, $10.3{\times}10^{-4}\;pg/cell\;and\;12.1{\times}10^{-4}\;pg/cell$, respectively, compared to the ethanol extracts. On the other hand, a treatment with the ethanol extract increased the specific secretion of $TNF-\acute{a}$ and IL-6 from human T cells, to $11{\times}10^{-4}\;pg/cell\;and\;14.3{\times}10^{-4}\;pg/cell$, respectively. The crude ethanol extract had the highest effect on the differentiation of human promyelocytic leukemia cells compared to the other extracts and Gomisin A and N. In general, the biological activities of the extracts gradually decreased as the purification process proceeded, which suggests that higher immunostimulatory activities can be maintained by adding the crude extracts of the fruits rather than by adding a single compound.

• 한국식품과학회지
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• 제54권4호
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• pp.386-390
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• 2022

This study aimed to investigate the biological and antibacterial activities of phenolics from Sambucus sieboldiana var. pendula leaf extract. The phenolic contents of the S. sieboldiana var. pendula extracted with water and ethanol was 11.60 and 12.39 mg/g, respectively. The inhibitory effects of the water and ethanol extracts on the angiotensin converting enzyme (ACE) were 71.94-92.08 and 48.42-78.33%, respectively, and on xanthine oxidase (XOase) were 42.11-100 and 35.61-100%, respectively, at a phenolic concentration of 50-200 ㎍/mL. All these effects were found to be concentration-dependent. Additionally, the leaf extracts exhibited excellent antibacterial activities against Streptococcus mutans, Staphylococcus aureus, and Propionibacterium acnes. Hence, S. sieboldiana var. pendula was confirmed to have excellent antihypertensive, antigout, and antimicrobial properties.

• 대한지구과학교육학회지
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• 제5권1호
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• pp.95-104
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• 2012

The purpose of this study is to examine what effects the experiment class to stress discussion of small groups in scientific experiment class of the elementary school has on scientific achievement and attitude on the science of the students comparing to the usual scientific experiment class. For that purpose, this study has divided 49 students at the 6th grade of the M elementary school in P City into test groups of 24 students and control groups of 25 students. Classes have been progressed by giving sufficient time to the test groups for discussion by each small groups after experiment while by allowing the control groups to finish the experiment with arrangement of the experiment results. Conclusions of this study include: First, the more familiar the experiment materials are and the easier the experiment procedures are to be operated by the students, the more actively the small group discussion activities have been deployed. It shows that the students need a certain level of background knowledge before experiment for vital discussing activities. Second, it is appeared that the test groups given the scientific experiment class stressing small group discussing activity have significantly high scores comparing to the control groups given the existing scientific experiment class. It shows that the small group discussing activities have effects on promoting understanding of the students on the scientific achievement for the scientific experiment class. Third, it is appeared that the test groups given the scientific experiment class stressing small group discussing activity significantly high scores on attitude about the science comparing to the control groups given the existing scientific experiment class. It is considered that the students could have opportunities to compare their own thoughts with others and to have reflective thought to change their thoughts through the small group discussing activity. As shown above, it shows that the experiment class to stress discussing activities is more effective to increase scientific achievement and attitude about the science than the scientific experiment class to get and arrange the experiment results from the existing experiment classes.

• 한국과학교육학회지
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• 제27권4호
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• pp.309-317
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• 2007

이 연구는 우리 과학수업환경에 적합한 문제해결 모형 및 학습자의 문제해결 활동 단계를 안내하는 활동도구를 개발하고, 이를 과학수업에 적용하여 중학생들의 문제해결 활동에 대한 인식을 알아보는데 있다. IDEAL, CPS, SSCS 문제해결 모형을 고찰하여, 문제해결 단계를 문제탐색, 계획실행, 결과발표, 발표평가 등의 4단계 선정하였다. 그리고 문제해결 단계별 활동요소를 선정하여 각각의 문제해결 단계를 안내하는 활동도구를 각각 개발하였다. 중학교 1학년 2개 학급 과학수업에 개발한 문제해결 모형 및 활동도구를 적용하여 중학생들의 문제해결 활동에 대한 인식을 조사하였다. 문제해결 활동은 과학수업에 더 참여적이고, 흥미를 갖게 하며, 실생활의 문제를 해결하는데 도움을 준다고 응답하였다. 따라서 문제해결 활동은 중학생들의 과학수업에 대한 긍정적인 인식을 갖게 하는데 유용한 교수학습활동이며 또한 실생활 소재의 문제해결 활동은 생활 주위에서 일어나는 문제에 흥미와 호기심을 가지고 실생활의 문제를 해결하려는 태도를 기르는데 유용한 교수학습활동이라 사료된다.

• 한국환경교육학회지:환경교육
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• 제22권4호
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• pp.81-94
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• 2009

This study was intended to develop the STS module regarding conservation of water resources, called "A Project for the Conservation of Water Resources". Since each theme consisted of 2 subject activities, they had total 8 subject activities. Developed STS module was applied to 113 male students of 11th grader of D High School in Incheon. After they received 8 periods of the developed STS module, the environmental sensitivity and environmental conservation behavior and the interest of the affective domains related to science were determined. Results were as follows; Four themes of this module were 'What are the water resources?', 'What is a main cause for the water pollution?', 'A drinking water? or non-drinking water?' and 'Making UCC for the water resources'. Since each theme consisted of 2 subject activities, they were for total 8 periods. Developed STS module was found to be appropriate for the STS and they could be applied to the classroom easily. Students who were instructed according to the developed STS module showed that there was a statistically significant enhancement in the environmental sensitivity and environmental conservation behavior and in the area of interest of the affective domains related to science. Students who were instructed according to the developed STS module showed positive responses to the instructional methods by STS. Based on students' interview, they revealed that they were impressed with the hands-on activities and the process of subject activities. Instruction with STS module seemed to be more appropriate way of teaching compared to the traditional way of teaching. However, it will be necessary to develop more modules or programs which could be linked from the elementary school level to the high school level and to use them consistently in order to maximize their effects.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.364-368
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• 2011

An experiment was conducted to examine the effects of Cordyceps militaris mycelia on microbial populations and fibrolytic enzyme activities in vitro. C. militaris mycelia was added to buffered rumen fluid with final concentrations of 0.00, 0.10, 0.15, 0.20, 0.25 and 0.30 g/L and incubation times were for 3, 6, 9, 12, 24, 36, 48 and 72 h. At all incubation times, the supplementation of C. militaris mycelia linearly increased the number of total viable and celluloytic bacteria; maximum responses were seen with 0.25 g/L supplementation of C. militaris mycelia. The addition of C. militaris mycelia above the level of 0.20 g/L significantly (p<0.01) increased the number of total and cellulolytic bacteria compared with the control. On the other hand, the response of fungal counts to the supplementation of C. militaris mycelia showed a linear decrease; the lowest response was seen with 0.30 g/L supplementation of C. militaris mycelia. It would seem that C. militaris mycelia possess a strong negative effect on rumen fungi since the lowest level of C. militaris mycelia supplementation markedly decreased fungal counts. Carboxylmethyl cellulase activities were linearly increased by the addition of C. militaris mycelia except at 3 and 9 h incubation times. At all incubation times, the supplementation of C. militaris mycelia linearly increased the activities of xylanase and avicelase. In conclusion, the supplementation of C. militaris mycelia to the culture of mixed rumen microorganisms showed a positive effect on cellulolytic bacteria and cellulolytic enzyme activities but a negative effect on fungi.

• 한국과학교육학회지
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• 제39권3호
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• pp.349-362
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• 2019

이 연구에서는 교육 소외계층 학생을 대상으로 하는 과학교육 프로그램으로서 사다리 프로젝트를 소개하고, 이 사업에서 수행된 과학 진로체험 활동이 교육 소외계층 학생들의 과학선호도와 진로성숙도에 미치는 효과를 알아봄으로써 교육 소외계층을 위한 과학교육 실천 활동의 의의와 시사점을 도출하고자 하였다. 이를 위하여 2017년도 사다리 프로젝트에 참여한 중고등학생을 대상으로 과학 진로체험 활동에 참여하기 전과 후의 과학선호도와 진로성숙도를 조사하고 응답 결과를 분석하였다. 연구 결과, 교육 소외계층 학생을 위한 과학 진로 체험 활동에 참여한 학생들의 과학선호도는 모든 하위영역에서 활동 이후 긍정적으로 변하였고, 이는 고등학생보다 중학생에게 더욱 잘 드러났다. 또한, 과학 진로체험 활동에 참여한 학생의 진로성숙도는 계획성, 희망 직업에 대한 지식, 진로 탐색 및 준비 행동 등에서 활동 이후 긍정적으로 변하였고, 이는 중학생보다 고등학생에게 더 잘 나타났다. 이 연구는 교육 소외계층 학생을 위한 국가 수준의 과학교육 사업에 대해 증거를 바탕으로 그 효과성을 제시했다는 점에서 의의가 있다. 더불어 교육 소외계층을 위한 과학교육의 목적 및 대상에 따라 과학 진로체험 활동의 내용과 성격이 달라져야 함을 시사한다.

• 과학교육연구지
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• 제36권1호
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• pp.35-48
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• 2012

이 연구에서는 2007 개정 교육과정에 따른 중학교 과학 1 교과서 '식물의 영양' 단원의 탐구활동과 이와 관련되는 제7차 교육과정에 따른 중학교 과학 2 교과서 '식물의 구조와 기능' 단원의 탐구활동을 탐구 내용 영역, 탐구 과정 영역, 탐구 상황 영역의 3차원 분석틀을 이용하여 분석하였다. '식물의 영양' 단원의 평균 탐구활동의 수는 9.2개로 '식물의 구조와 기능' 단원의 경우보다 3.8개 줄었다. 그리고 두 단원에서 공통적으로 다루는 주제도 있는 반면, 교육과정 개정에 따른 내용의 변화를 반영하여 중점을 두는 탐구활동 주제가 달라진 경우도 있었다. 두 단원 모두 기초 탐구 과정에서는 '관찰', 통합 탐구 과정에서는 '자료해석'의 비율이 높았고, '실험관찰'에 해당되는 비율이 매우 높게 나타났으며, '순수과학적 상황'의 비율이 높게 나타났다. '식물의 영양' 단원에서는 기초 탐구 요소보다 통합 탐구 요소를 더 많이 다루고 있고, '해보기'에 해당하는 탐구활동 수가 증가하고 '모의활동'이 제시된 점이 특징적이며, '개인적 상황'의 비율이 늘었고 '기술적 상황'과 '자연환경적 상황'이 제시된 탐구활동도 나타났다. 중학교 과학 교과서 개발 시 탐구활동이 보다 다양해지도록 탐구활동의 내용, 탐구 과정, 유형, 상황 등의 측면을 고려해야 할 것이다.