• 제목/요약/키워드: Life Science I

검색결과 3,237건 처리시간 0.033초

Examination of Students' Perceptions of the Selection of Science Subjects in High School Credit System and Their Reasons for Selection

  • Dong-Seon Shin;Jong Keun Park
    • International Journal of Advanced Culture Technology
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    • 제11권4호
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    • pp.263-272
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    • 2023
  • We investigated and analyzed students' perceptions of their choice of science subjects in the high school credit system and the reasons for their choice. To achieve this, the selection of science subjects was investigated for the second year of S high school over the past three years. Students selected an average of 1.54 science subjects, and it was found that the rate of selection of science subjects was gradually increasing by year. Students chose high in the order of life science I, earth science I, chemistry I, physics I, etc. in the science subject group. Students who wish to enter the natural and engineering fields chose life science I, chemistry I, physics I, etc., while, students who wish to enter the humanities society chose society and culture, life science I, ethics and thought, etc. On the other hand, the reason for choosing science subjects was 'related to college admission', followed by 'aptitude and interest', 'career and real life help', etc. physics I, chemistry I, etc., were high in the subjects selected according to the 'related to college admission'. The subjects selected according to 'aptitude and interest' were high in life science I, earth science I, etc. Physics I, chemistry I, etc. are recognized as subjects necessary for college entrance, and life science I, earth science I, etc., are found to be related to their interests and aptitudes.

Inhibitory Action of Tsunokaori Tangor Peel on the Lipopolysaccharide-Induced Inflammatory Response in RAW 264.7 Macrophage Cells

  • Choi, Soo-Youn;Hwang, Joon-Ho;Ko, Hee-Chul;Park, Soo-Young;Kim, Gi-Ok;Kim, Duck-Hee;Chang, Ih-Seop;Kwon, H.-Moo;Kim, Se-Jae
    • Food Science and Biotechnology
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    • 제15권2호
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    • pp.270-276
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    • 2006
  • We evaluated the effects of extracts of Tsunokaori tangor peel on lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin $E_2\;(PGE_2)$ in RAW 264.7 cells. The ethyl acetate fraction of Tsunokaori tangor peel (EA-TTP) markedly inhibited the production of NO and $PGE_2$ in LPS-stimulated RAW 264.7 cells. Consistent with these findings, the expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins were down-regulated in a dose-dependent manner. Additionally, EA-TTP decreased the expression iNOS mRNA but not COX-2 mRNA. To determine the upstream signaling mechanism for the down-regulation of LPS-induced iNOS expression, we investigated the effect of EA-TTP on the degradation and re-synthesis of $I{\kappa}B{\alpha}$. EA-TTP dose-dependently delayed $I{\kappa}B{\alpha}$ degradation and increased $I{\kappa}B{\alpha}$ re-appearance following degradation, suggesting this as the mechanism by which EA-TTP suppressed iNOS gene expression. The EA-TTP also dose-dependently reduced the expression of the cellular stress-response protein heme oxygenase-1, and inhibited the LPS-induced sustained activation of extracellar signal-regulated kinase (ERK).

Selection of iPSCs without mtDNA deletion for autologous cell therapy in a patient with Pearson syndrome

  • Yeonmi Lee;Jongsuk Han;Sae-Byeok Hwang;Soon-Suk Kang;Hyeoung-Bin Son;Chaeyeon Jin;Jae Eun Kim;Beom Hee Lee;Eunju Kang
    • BMB Reports
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    • 제56권8호
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    • pp.463-468
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    • 2023
  • Screening for genetic defects in the cells should be examined for clinical application. The Pearson syndrome (PS) patient harbored nuclear mutations in the POLG and SSBP1 genes, which could induce systemic large-scale mitochondrial genome (mtDNA) deletion. We investigated iPSCs with mtDNA deletions in PS patient and whether deletion levels could be maintained during differentiation. The iPSC clones derived from skin fibroblasts (9% deletion) and blood mononuclear cells (24% deletion) were measured for mtDNA deletion levels. Of the 13 skin-derived iPSC clones, only 3 were found to be free of mtDNA deletions, whereas all blood-derived iPSC clones were found to be free of deletions. The iPSC clones with (27%) and without mtDNA deletion (0%) were selected and performed in vitro and in vivo differentiation, such as embryonic body (EB) and teratoma formation. After differentiation, the level of deletion was retained or increased in EBs (24%) or teratoma (45%) from deletion iPSC clone, while, the absence of deletions showed in all EBs and teratomas from deletion-free iPSC clones. These results demonstrated that non-deletion in iPSCs was maintained during in vitro and in vivo differentiation, even in the presence of nuclear mutations, suggesting that deletion-free iPSC clones could be candidates for autologous cell therapy in patients.

한 사범대학 과학 교육 조교수의 삶에 대한 자서전적 연구 (Autobiographic Research on the Life of an Assistant Professor of Science Education at a College of Education)

  • 한재영
    • 과학교육연구지
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    • 제36권1호
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    • pp.1-13
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    • 2012
  • 사범대학 조교수는 어떤 삶을 살고 있는가? 이 연구의 목적은 한 지방 국립 사범대학 조교수의 삶을 탐색하여 과학 교육 연구자 및 교사 교육자로서의 삶의 모습을 기술하고 이해하는 것이다. 연구자 스스로 삶을 정리하고 반성하는 자서전적 연구를 수행하였다. 조교수의 삶이 담겨진 기록들을 수집한 후 그것을 분류하는 틀을 개발하였다. 조교수의 삶을 대학에서의 삶과 개인적인 삶으로 크게 분류하고, 대학에서의 삶은 다시 교육, 연구, 봉사로, 개인적인 삶은 본인과 가정으로 구분하였다. 나의 다양한 삶의 모습에서 '변화'와 '학습'의 핵심 주제를 찾았고, 그에 해당하는 삶의 내용을 재구성하여 제시하였다. 그리고 조교수 시기의 나를 '자신에게서 타인으로', '어울림과 고립의 조화', '끊임없는 배움으로 운신의 폭 증가'로 표현할 수 있었다. 나의 삶에 대한 이해와 반성을 통해 사범대학 교수의 역할을 되짚어보고 교육적인 시사점을 논의하였다.

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Pathogenesis strategies and regulation of ginsenosides by two species of Ilyonectria in Panax ginseng: power of speciation

  • Farh, Mohamed El-Agamy;Kim, Yu-Jin;Abbai, Ragavendran;Singh, Priyanka;Jung, Ki-Hong;Kim, Yeon-Ju;Yang, Deok-Chun
    • Journal of Ginseng Research
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    • 제44권2호
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    • pp.332-340
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    • 2020
  • Background: The valuable medicinal plant Panax ginseng has high pharmaceutical efficacy because it produces ginsenosides. However, its yields decline because of a root-rot disease caused by Ilyonectria mors-panacis. Because species within Ilyonectria showed variable aggressiveness by altering ginsenoside concentrations in inoculated plants, we investigated how such infections might regulate the biosynthesis of ginsenosides and their related signaling molecules. Methods: Two-year-old ginseng seedlings were treated with I. mors-panacis and I. robusta. Roots from infected and pathogen-free plants were harvested at 4 and 16 days after inoculation. We then examined levels or/and expression of genes of ginsenosides, salicylic acid (SA), jasmonic acid (JA), and reactive oxygen species (ROS). We also checked the susceptibility of those pathogens to ROS. Results: Ginsenoside biosynthesis was significantly suppressed and increased in response to infection by I. mors-panacis and I. robusta, respectively. Regulation of JA was significantly higher in I. robusta-infected roots, while levels of SA and ROS were significantly higher in I. mors-panacis-infected roots. Catalase activity was significantly higher in I. robusta-infected roots followed in order by mock roots and those infected by I. mors-panacis. Moreover, I. mors-panacis was resistant to ROS compared with I. robusta. Conclusion: Infection by the weakly aggressive I. robusta led to the upregulation of ginsenoside production and biosynthesis, probably because only a low level of ROS was induced. In contrast, the more aggressive I. mors-panacis suppressed ginsenoside biosynthesis, probably because of higher ROS levels and subsequent induction of programmed cell death pathways. Furthermore, I. mors-panacis may have increased its virulence by resisting the cytotoxicity of ROS.

Pseudomonas sp. LG2의 Ferulic acid esterase 및 Xylanase 유도와 부분적 특성 (Partial Characterization and Induction of Ferulic Acid Esterase and Xylanase from Pseudomonas sp. LG2)

  • 김용균;이상몽;박현철;김근기;손홍주
    • 생명과학회지
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    • 제17권4호
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    • pp.568-574
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    • 2007
  • 리그닌 분해 세균인 Pseudomonas sp. LG2는 lignocellulose 기질을 분해하여 APPL 화합물을 생성하는 균주이다. 이 균주를 BSG(brewer's spent grain)가 함유된 배지에서 배양한 배양액에서 APPL 화합물을 확인하였다. 세포외 조효소들의 유도에 관한 여러 가지 탄소원의 영향을 조사한 결과 glucose 배지에서는 xylanase의 효소활성만 확인 되었고 xylose, arabinose에서 배양한 조효소에서는 FAE 및 xylanase의 효소활성이 없었다. Oat spelt xylan, HBSG I(hydrolyzed brewer's spent grain I), HBSG II(hydrolyzed brewer's spent grain II) 및 AFBSG(autoclaved fraction from brewer's spent grain)를 탄소원으로 배양한 조효소에서는 FAE 및 xylanase의 효소활성이 확인됐다. Pseudomonas sp. LG2를 oat spelt xylan, HBSG I, HBSG II 및 AFBSG를 탄소원으로 사용하여 14일 동안 배양하면서 배양기간에 따른 세포외 효소들의 FAE와 xylanase 활성을 조사하였다. Xylanase의 최고 활성은 xylan을 탄소원으로 6일간 배양 했을때 5.3 U/mg으로 가장 높았으며, FAE의 최고 활성은 AFBSG를 탄소원으로 배양했을 때 배양 8일째 15.4 mU/mg으로 가장 높았다. Oat spelt xylan, HBSG I, HBSG II 및 AFBSG를 탄소원으로 사용하여 배양한 배지에 분리된 ferulic acid가 확인되었다. 세포외 효소의 FAE 활성은 methyl ferulic acid, methyl caffeic acid, methyl p-coumaric acid에 대해 esterase의 활성을 보였으나, methyl sinapinic acid, methyl vanillic acid 및 methyl gallic acid에 대해서는 esterase의 활성이 없었다.

Reproductivity of Cloned Male Cat

  • Choi, E.G.;Lee, H.S.;Yin, X.J.;Ho, J.H.;Cho, E.M.;Kang, S.H.;Bae, I.H.;Cho, S.K.;Kong, I.K.
    • 한국발생생물학회:학술대회논문집
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    • 한국발생생물학회 2005년도 제5회 발생공학 국제심포지엄 및 학술대회
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    • pp.129-129
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    • 2005
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