• 제목/요약/키워드: Pauling

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SUPPRESSION BY CHLOROPHYLL, BUT PROMOTION BY CHLOROPHYLLIN, OF COLON CARCINOGENESIS IN THE FISHER 344 RAT

  • Blum, Carmen A.;Xu, Meirong;Orner, Gayle A.;Diaz, G.Dario;Li, Qingjie;Bailey, George S.;Dashwood, Roderick H.
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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    • pp.48-49
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    • 2001
  • The carcinogens 2-amino-3-methylimidazo[4, 5-f]quinoline (IQ) and 1, 2-dimethylhydrazine (DMH) induce colon tumors in the Fisher 344 rat that contain mutations in Ctnnbl, the gene for b-catenin, but the pattern of mutation differs from that found in human colon cancers. In both species, mutations affect the glycogen synthase kinase 3$\beta$ (GSK-3$\beta$) consensus region of $\beta$-catenin, but whereas they directly substitute critical Ser/Thr phosphorylation sites in human colon cancers, the majority of mutations cluster around Ser$_{33}$ in the rat tumors.(omitted)d)

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SUPPRESSION BY CHLOROPHYLL, BUT PROMOTION BY CHLOROPHYLLIN, OF COLON CARCINOGENESIS IN THE FISHER 344 RAT

  • Blum, Carmen A.;Xu, Meirong;Orner, Gayle A.;Diaz, G.Daria;Li, Qingjie;Bailey, George S.;Dashwood, Roderick H.
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2001년도 International Symposium on Effects of Edible Phytochemicals and Their Synthetic Derivatives on Carcinogenesis and Mutagenesis
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    • pp.5-6
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    • 2001
  • The carcinogens 2-arnioo-3-methylimidazo[4,5-f]quinoline (IQ) and 1,2-dimethylhydrazine (DMH) induce colon tumors in the Fisher 344 rat that contain mutations in Ctnnb1, the gene for b-catenin, but the pattern of mutation differs from that found in human colon cancers. in both species, mutations affect the glycogen synthase kinase 3$\beta$ (GSK-3$\beta$) consensus region of $\beta$-catenin, but whereas they directly substitute critical Ser/Thr phosphorylation sites in human colon cancers, the majority of mutations cluster around Ser$^{33}$ in the rat tumors.(omitted)

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과학영재를 가르치기 위한 창의적 화학자 폴링의 연구과정 분석 (Analyzing the Creative Process of the Pauling's Research for Science Gifted Education)

  • 구민아;김지영;박종석;김영민;서혜애
    • 영재교육연구
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    • 제21권4호
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    • pp.945-959
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    • 2011
  • 과학영재를 가르칠 때 고려해야할 중요한 요소로 거론 되는 것 중 하나는 창의성이다. 과학 영재들에게 창의성을 향상시키는 방법은 여러 가지가 있지만, 과학자처럼 사고하고 탐구할 수 있는 기회를 제공하는 것도 한 가지 방법이다. 이에 이 연구에서는 과학영재의 창의성을 신장시키기 위해 창의적 화학자 '폴링'의 연구과정을 분석하였다. 분석에 활용한 자료는 폴링의 일대기와 연구 사례, 인터뷰 자료들이다. 이러한 자료들을 분석하여 창의적 사고방법과 연구방법 요소들을 각각 추출할 수 있었다. 창의적 사고방법 요소로는 귀추적 사고, 모순, 관점의 전환, 모형화, 단순화, 은유적 사고, 발산적 사고, 수렴적 사고가 추출되었다. 연구방법 요소는 반복 실험, 공동연구, 이론과 실험의 병행, 과학자의 사회적 책임이 추출되었다. 이러한 요소들을 과학영재를 지도할 때 사용하는 교육프로그램에 포함시킨다면 과학영재들은 창의적 과학자와 같은 행동을 따라함으로써 창의성 신장에 도움이 될 것이다.

Comprehensive Studies on the Free Energies of Solvation and Conformers of Glycine: A Theoretical Study

  • Kim, Chang-Kon;Park, Byung-Ho;Lee, Hai-Whang;Kim, Chan-Kyung
    • Bulletin of the Korean Chemical Society
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    • 제32권6호
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    • pp.1985-1992
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    • 2011
  • The stable conformers of glycine and the inter-conversions between them were studied theoretically at various levels of theory, B3LYP, MP2, CCSD and CCSD(T), in the gas phase and in aqueous solution. In aqueous solution, the structures examined by use of the conductor-like polarizable continuum model (CPCM) with various cavity models, UA0, UAHF, UAKS, UFF, BONDI and PAULING, and by use of a discrete/continuum solvation model with eight water clusters. The Gibbs free energy differences between the neutral (NE) and zwitterionic conformers (ZW), ${\Delta}G_{Z-N}[=G_{ZW}-G_{NE}]$, in aqueous solution were well reproduced by using the BONDI and PAULING cavity models. However the ${\Delta}G_{Z-N}$ values were underestimated in other cavity models, although the ZW conformers existed as stable species in aqueous solution. In the studies of a discrete/continuum solvation model with eight water clusters, gas phase results are still insufficient to reproduce the experimental findings. However the ${\Delta}G_{Z-N}$ values calculated by use of CPCM method in aqueous solution agreed well with the experimental ones.

계면활성제의 친수.소수성 그룹의 부분전하와 CMC특성 (양이온 및 양쪽성 계면활성제) (Partial Charge and CMC Characteristics of Hydrophilic and Hydrophobic Group of Surfactants (Cationic and Amphoteric Surfactant))

  • 하윤식
    • 한국환경과학회지
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    • 제9권5호
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    • pp.403-408
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    • 2000
  • On the basis of theory of Bratsch's electronegativity equalization the electronegativity equalization the group electronegativities and the group partial charges for cationic and amphoteric surface and amphoteric surfactants could be calculated using Pauling's electronegativity parameters. From calculated output we have investigated relationships between CMC(critical micelle concentration) and partial charge and group electronegativity of hydrophilic and hydrophobic groups structural stability of micelle for cationic and amphoteric surfactants. As a result CMC depends upon partial charge and electronegativity of hydrophilic group is decreased. With increasing the carbon number of hydrophilic group for cationic surfactant its partial charge is increased but CMC and its electronegativity are decreased. With increasing the carbon number of hydrophobic group for cationic and amphoteric surfactant its partial charge is increased but CMC andits electronegativity are decreased.

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