• 제목/요약/키워드: Affinity

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Miscanthus sinensis와 타 식물과의 친근성에 관한 연구 (The studies on affinity between Miscanthus sinensis and other plants)

  • 이일구
    • Journal of Plant Biology
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    • 제13권4호
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    • pp.1-11
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    • 1970
  • Althought allelopathy has been cleary established for Pinus densiflora by Lee-Monsi, the auther suspected that Miscanthus sinensis which grows vigrously in such Korean pine forests might also exhibit the phenomenon. A total of 33 species having an affinity in the Miscanthus group were recorded in the filed. Out of these, five species; Patrinia scabiosaefolia, Lespedeza crytobotrya. Oenothera odorata, Raphanus sativus var. acanthiformis, and Zoysia japonica were considered the "A" group. Five other species which have no affinity to Misanthus sinensis, Amaranthus patulus, Solanum nigrum, Capsella bursa-pastoris var. triangularis, Chemopodium album var. centrorubrum and Alopeculus amurensis were considered the "B" group. Extracts of Miscanthus sinensis were applied to determine relative germination and growth. It was found the growth in the "B" group was promoted by a cold water extract of Miscanthus stems and leaves, but inhibited remarkably by an extract obtained by passing cold water through Miscanthus root. As expected, growth in the "A" group was promoted by both experimental treatments.romoted by both experimental treatments.

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Electron Emitter of Negative Electron Affinity Diamond

  • Hiraki, Akio;Ogawa, Kenji;Eimori, Nobuhiro;Hatta, Akimitsu
    • The Korean Journal of Ceramics
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    • 제2권4호
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    • pp.193-196
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    • 1996
  • A new type of electron emitter device of chemical-vapor-deposited diamond thin film is proposed. The device is a diode of metal-insulator-insulator-semiconductor (MIS) structure consisting of an intrinsic polycrystalline diamond film as the insulator, an aluminium electrode on one side, and hydrogenated diamond surface on the other side as the p-type semconductor with negative electron affinity (NEA). Electrons will be injected and/or excited to the conduction band of intrinsic diamond layer to be emitted from the hydrogenated diamond surface of NEA.

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An anomalous dissociation of protonated cluster ions of DNA guanine-cytosine base-pair

  • Seong, Yeon-Mi;Han, Sang-Yun;Jo, Sung-Chan;Oh, Han-Bin
    • Mass Spectrometry Letters
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    • 제2권3호
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    • pp.73-75
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    • 2011
  • In the collisionally-activated dissociation of the proton-bound cluster ions of DNA base guanine (G) and cytosine (C), $G{\bullet}{\bullet}H^+{\bullet}{\bullet}C$, the abundance of [$CH^+$] ions was found to be higher than that of [$GH^+$] despite the fact that G has a higher proton affinity than C. This unexpected observation seems to demonstrate another example that the simple kinetic method scheme does not work. We suggest that a kinetic factor or detailed dynamics governing the proton transfer and dissociation should be carefully considered in the applications of the kinetic method to the proton affinity measurements.

공통 이웃 그래프 밀도를 사용한 소셜 네트워크 분석 (Social Network Analysis using Common Neighborhood Subgraph Density)

  • 강윤섭;최승진
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제16권4호
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    • pp.432-436
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    • 2010
  • 소셜 네트워크를 비롯한 네트워크로부터 커뮤니티를 발견하려면 네트워크의 노드를 그룹 내에서는 서로 조밀하게 연결되고 그룹 간에는 연결의 밀도가 낮은 그룹들로 군집화하는 과정이 꼭 필요하다. 군집화 알고리즘의 성능을 위해서는 군집화의 기준이 되는 유사도 기준이 잘 정의되어야 한다. 이 논문에서는 네트워크 내의 커뮤니티 발견을 위해 유사도 기준을 정의하고, 정의한 유사도를 유사도 전파(affinity propagation) 알고리즘과 결합하여 만든 방법을 기존의 방법들과 비교한다.

Kinetic analysis of Drosophila Vnd protein containing homeodomain with its target sequence

  • Yoo, Si-Uk
    • BMB Reports
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    • 제43권6호
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    • pp.407-412
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    • 2010
  • Homeodomain (HD) is a highly conserved DNA-binding domain composed of helix-turn-helix motif. Drosophila Vnd (Ventral nervous system defective) containing HD acts as a regulator to either enhance or suppress gene expression upon binding to its target sequence. In this study, kinetic analysis of Vnd binding to DNA was performed. The result demonstrates that DNA-binding affinity of the recombinant protein containing HD and NK2-specific domain (NK2-SD) was higher than that of the full-length Vnd. To access whether phosphorylation sites within HD and NK2-SD affect the interaction of the protein with the target sequence, alanine substitutions were introduced. The result shows that S631A mutation within NK2-SD does not contribute significantly to the DNA-binding affinity. However, S571A and T600A mutations within HD showed lower affinity for DNA binding. In addition, DNA-binding analysis using embryonic nuclear protein also demonstrates that Vnd interacts with other nuclear proteins, suggesting the existence of Vnd as a complex.

락토스 오페론에서 Cyclic AMP Receptor Protein에 의한 두 결합 부위(CRP1과 CRP2)의 결합 특성에 관한 연구 (The Binding Affinities of Two Binding Sites(CRP1 and CRP2 Sites) by Cyclic AMP Receptor Protein at Lactose Operon)

  • 강종백;권건
    • 생명과학회지
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    • 제13권5호
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    • pp.746-750
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    • 2003
  • Lactose operon contains two CRP binding sites at promoter(CRP1 site) and operator(CRP2 site) regions at lac operon. CRP protein can bind to both sites with the different binding affinity. CRP1 site, major CRP binding site, acts the transcription activation with the fully unknown mechanism by binding of CRP. In this study, the binding affinities of CRP1 site and CRP2 site were measured with the fluorescein-labeled oligomers, which contain CRP1 site and the three different spacing sequences between GTGA and TCAC at CRP2 site. Results showed that CRP:cAMP complex bound to CRP1 site 3 times more strongly than CRP2 site and the base spacing between GTGA and TCAC was not the only factor to affect the binding affinity of CRP to CRP2 site.

Neurospora crassa의 액포에 존재하는 arginine transporter의 표지방법 (Affinity labeling of the Vacuolar Arginine Transporter in Neurospora crassa)

  • 이연희
    • 미생물학회지
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    • 제27권2호
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    • pp.108-116
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    • 1989
  • 액포에 존재하는 arginine 운반체의 인식 특이성에 근거하여 NBZ arginyl diazomethane을 합성, affinity label로 사용하였다. 이 arginyl derivative는 ATP-dependent와 ATP-indepndent에 의한 arginine 운반작용을 억제하였다. 액포에의 결합은 비역가적이며, 강한 염기에 의해 분리되었다. Cysteine을 blocking 시키면, 결합은 일어나지 않았다.

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온톨로지 학습을 위한 Affinity Propagation 기반의 도메인 컨셉 자동 획득 기법에 관한 연구 (Automatic Acquisition of Domain Concepts for Ontology Learning using Affinity Propagation)

  • 이크발카심;정진우;이동호
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(C)
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    • pp.168-171
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    • 2011
  • One important issue in semantic web is identification and selection of domain concepts for domain ontology learning when several hundreds or even thousands of terms are extracted and available from relevant text documents shared among the members of a domain. We present a novel domain concept acquisition and selection approach for ontology learning that uses affinity propagation algorithm, which takes as input semantic and structural similarity between pairs of extracted terms called data points. Real-valued messages are passed between data points (terms) until high quality set of exemplars (concepts) and cluster iteratively emerges. All exemplars will be considered as domain concepts for learning domain ontologies. Our empirical results show that our approach achieves high precision and recall in selection of domain concepts using less number of iterations.

쥐 심근 세포의 $[^3H]$ Ouabain 결합과 $^{45}Ca^{2+}}$섭취에 미치는 Ouabain의 영향 ($[^3H]$ Ouabain Binding and Effect of Ouabain on $^{45}Ca^{2+}$-Uptake in Rat Cardiac Myocytes)

  • 이신웅;김영희;진갑덕
    • 약학회지
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    • 제28권3호
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    • pp.129-138
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    • 1984
  • Specific [$^{3}H$] ouabain binding and $Ca^{2+}$ -uptake were measured to elucidate the role of high affinity [$^{3}H$] ouabain binding site in rat cardiac myocytes which contain 65% of rod cells. High affinity [$^{3}$H] ouabain binding site, which is about 3% of total pump sites, with apparent dissociation constant ($K_{D}$) of $1.1{\times}10^{-7}M$ and maximum binding site concentration (Bmax) of 1.2 pmol/mg protein ($1.754{\times}10^{5}cells$) were identified. At the concentration of $10^{-7}M$ to $10^{-4}M$, ouabain produced concentration dependent increase in $Ca^{2+}$-uptake of myocytes. The effect of ouabain on $Ca^{2+}$-uptake was not effected by membrane depolarization (elevated K+ in incubation medium) or verapamil. These results suggest that in rat ventricular myocytes the ouabain receptor complex to high affinity site may increase Na+ - $Ca^{2+}$ exchange across the sarcolemmal membrane by inhibition of Na+, K+ - ATPase.

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박테리오파아지 표면 발현 시스템을 이용한 Maackia amurensis Hemagglutinin (MAH)의 기능적 발현 (Functional Display of Maackia amurensis Hemagglutinin (MAH) on Bacteriophage)

  • 임미정
    • 약학회지
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    • 제47권3호
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    • pp.176-179
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    • 2003
  • A library of unlimited number of novel lectins with diverse specificities has been previously generated by randomly mutating the carbohydrate-recognition domain of Maackia amurensis hemagglutinin (MAH). To establish the experimental environment capable of selecting high affinity mutant lectins in E. coli, phage display system was adapted. Carbohydrate binding capacity of two phagemid vectors, pComb3 and pComb8 displaying wild-type MAH lectin was assessed. Specific bindings of pComb3 and pComb8 phages expressing w.t. MAH to affinity-purified polyclonal anti-MAH antibody and to glycophorin was demonstrated. Both phages also showed strong hemagglutinating activity to intact but not sialidase-treated human erythrocytes, which is consistent to the specificity of native MAH. Taken together, two different phage display vectors successfully allowed the expression of active MAH as a fusion protein on the surface of bacteriophage, which will lead to preparation of unique plant lectins with high affinity toward a variety of carbohydrate chains.