• Applied Biological Chemistry
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• 제48권3호
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• pp.292-295
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• 2005

Branched methyl group을 가지는 아프리카산 난(Aerangis confusa, Aerangis kirkii) 꽃의 천연향기성분인 methyl 3-methyloctanoate를 값싼 미생물 발효산물인 itaconic acid를 출발 물질로 하여 제조한 branched metyl group을 부분구조로 가지는 2-methyl-1,4-butandiol를 중간체로 하여 전 공정 9단계로 합성하였다. 최종 향기성분 metyl 3-methyloctanoate의 methyl ester대신 다양한 알킬 ester 화합물을 합성하여 그 향을 비교한 결과 서로 상이한 향 특성을 나타내므로 화장품이나 식품산업에 있어서 유용한 향료조성물의 첨가소재로 개발 가능하리라 사료된다.

• 한국초등과학교육학회지:초등과학교육
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• 제40권1호
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• pp.13-21
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• 2021

This study analyzed the effects of 'online biology learning using E-learning system' on elementary school students' science-related attitudes. Samples of the study were composed of 95 sixth-grade students of N elementary school in Seoul, Korea. The learning was conducted for 11 times over a month. The main results of this study are as follows. First, for the paired t-test, a statistically significant difference between the pre and post scores of science-related attitudes was found. After conducting the online biology learning science related attitudes scores of students generally declined. "The boredom caused by simply watching online biology contents" is the decisive cause of the decline in science-related attitude scores analyzed through interviews. Second, in ANCOVA, according to 'levels of meta-cognition'. there was no statistically significant difference in scores of science-related attitudes. but, there was statistically significant difference in science-related attitudes according to 'adoption of scientific attitudes'. Students of high meta-cognition type showed a greater decline in scores than students of low meta-cognition type. Based on the results of this study, implications for research of online biology education and elementary science education are discussed.

• 대한약리학회지
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• 제30권2호
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• pp.167-179
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• 1994

Recent evidence indicates that glial cells have a wide range of funtions which are critical for maintaining a balanced homeostatic environment in the central nervous system(CNS) peripheral nervous system(PNS). Morever, astrocytes are known to participate in the tissue repair and neuroimmunologic events within the CNS through many kinds of growth factors and cytokines. We investigated the effect of $TGF\;{\beta}_1$, on the growth and biochemical changes of rat glial cells in culture. The proliferative effect was determined by $^3H-thymidine$ uptake and the double immunostain with anti-cell-specific marker and anti-Bromodeoxyuridine(BrdU) antibody. To check the effect of biochemical changes we compared the amounts of glial fibrillar acidic protein(GFAP) and the activity of glutamine synthetase(GS) in astrocyte. And the amounts of myelin basic protein and the activity of 2',3'-cyclic nucleotide phosphohydrolase(CNPase) were measured in oligodendrocyte and the amounts of peripheral myelin in Schwann cell. When $TGF\;{\beta}_1$, was treated for 2 days with cultured glial cell, $TGF\;{\beta}_1$, decreased the $^3H-thymidine$ uptake and proliferation index of double immunostain of astrocytes, which indicates the inhibition of astroglial DNA synthesis, but stimulated the growth of Schwann cell. Also, $TGF\;{\beta}_1$, decrease the GS activity and increased the amounts of GFAP in astrocyte. In the case of Schwann cells the amounts of peripheral myelin was increased when treated with $TGF\;{\beta}_1$. However, $TGF\;{\beta}_1$, didn't show any effect on the proliferation and biochemical changes in oligodendrocyte. These results suggest that $TGF\;{\beta}_1$, might have a critical action in the regulation of proliferation and biochemical changes in glial cells, especially astrocyte.

• 대한물리의학회지
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• 제13권4호
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• pp.131-138
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• 2018

PURPOSE: This study was conducted to compare the muscle activity of the proximal muscles of the lower limb according to the distance between the front and rear foot during lunge and to determine the most effective foot position for activation of the proximal muscle in the limb. METHODS: A total of 49 young adults were enrolled in this study. All subjects performed lunge by positioning the big toe of the back foot and the heel of the front foot at intervals of 40%, 60%, and 80% of the subject's own leg length. Muscle activity of the vastus medialis oblique, rectus femoris (RF), vastus lateralis oblique (VLO), gluteus medius, biceps femoris, and semitendinosus (ST) was then measured during three intervals of lunge operation. Each operation was measured three times for 10 seconds each, after which the average value was calculated and analyzed. RESULTS: There were significant differences in muscle activities of RF, VLO, and ST among the three intervals of the foot (p<.05). Post hoc, comparisons revealed lunge at 40% intervals resulted in higher RF and VLO activity than at 60% and 80% intervals (p<.05). In the semitendinosus muscle, 80% leg length intervals showed higher muscle activity than 40% (p<.05). CONCLUSION: Strengthening of the proximal muscles of the lower extremities during lunge exercise is considered to be most effective when placing the fore- and rear foot at intervals corresponding to 40% of the leg length.

• 한국초등과학교육학회지:초등과학교육
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• 제40권4호
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• pp.545-555
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• 2021

이 연구의 목적은 '초등과학교육' 학술지의 변천 과정에 따른 연구 동향을 분석하는 것이다. 이 연구에서는 1983년 1권 1호부터 2020년 39권 4호까지 총 1,047편의 논문을 분석하였다. 연구의 결과는 다음과 같다. 첫째, '초등과학교육' 학술지의 변천 과정은 논문 편수에 급격한 변화가 있는 시점을 기준으로 태동기, 정착기, 발전기, 유지기로 구분하였다. 둘째, '초등과학교육' 학술지에 3인 이상의 연구와 순수·연구비 지원 연구가 감소하고 있었다. 셋째, 연구 대상은 초등학생과 초등교사에 관한 연구 비율이 높았다. 넷째, 연구 방법은 주로 조사연구와 실험연구이었고, 자료 분석 방법으로는 질적 분석과 혼합 분석 연구가 증가하고 있었다. 다섯째, 1 저자의 직업은 교수(45.6%), 교사(39.8%), 대학원생(10.6%), 연구원(1.7%) 순이었다. 여섯째, 교신저자의 지역은 수도권인 서울과 경인에 집중되었다. 마지막으로, '초등과학교육' 학술지가 미래의 초등과학교육을 선도하는데 중추적인 역할을 계속 수행하기 위해서는 학술지 전반에 대한 개선 노력과 국내외 연구자, 학회 임원과 회원, 교육 기관의 지속적인 참여와 협조가 필요하다.