• 영재교육연구
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• 제13권4호
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• pp.119-140
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• 2003

이 연구의 목적은 초·중·고등학교의 교육현장에서 창의성의 영역성이 어떻게 나타나는가를 실증적으로 검증하는 것이다. 연구대상을 전체학생 집단, 고창의성 집단, 저창의성 집단의 3개 집단으로 구분하여 각 집단에서의 영역성을 비교 규명하는 것이다. ‘능력-분화가설’에 기초하여, 4개 영역간의 상관관계, 영역-일반성의 변인과 영역-특수성의 영역간의 상관관계, 그리고 영역-특수성에 대한 영역-일반성의 상대적 예측력을 분석하였다. 연구결과, 연구가설과는 오히려 반대의 결과가 나타났다. 즉, 저창의성 집단에서는 영역-특수성을 지지하였으나, 전체학생과 고창의성 집단에서 영역-일반성과 영역-특수성의 어느 한쪽을 일방적으로 지지하기 어려운 결과가 나타났다. 오히려 영역-일방성과 영역-특수성이 상호 보완 또는 통합되는 영역-상보설이 지지되었다.

• 대한수학회논문집
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• 제24권3호
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• pp.425-432
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• 2009

This paper introduces a local non-positivity of two set-valued mappings (F,Q) and considers the existences and properties of solutions for set-valued mixed vector FQ-implicit variational inequality problems and set-valued mixed vector FQ-complementarity problems in the neighborhood of a point belonging to an underlined domain K of the set-valued mappings, where the neighborhood is contained in K. This paper generalizes and extends many results in [1, 3-7].

• 대한기계학회논문집
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• 제18권8호
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• pp.2026-2038
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• 1994

A numerical scheme is developed for the analysis of incipient sliding contact with orthotropic friction condition subjected to tangential load and twisting moment. The inherent nonlinearity in the orthotropic friction law has been treated by a polyhedral friction law. Then, a three-dimensional linear complementarity problem(LCP) formulation in an incremental form is obtained, and the existence of a solution is investigated. A Lemke's complementary pivoting algorithm is used for solving the LCP. The scheme is illustrated by spherical contact problems, and the effects of eccentricity of elliptical friction domain on the traction and stick region are discussed.

• Ocean and Polar Research
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• 제33권2호
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• pp.159-169
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• 2011

Antifreeze proteins (AFPs) have ice binding affinity, depress freezing temperature and inhibit ice recystallization which protect cellular membranes in polar organisms. Recent structural studies of antifreeze proteins have significantly expanded our understanding of the structure-function relationship and ice crystal growth inhibition. Although AFPs (Type I-IV AFP from fish, insect AFP and Plant AFP) have completely different fold and no sequence homology, they share a common feature of their surface area for ice binding property. The conserved ice-binding sites are relatively flat and hydrophobic. For example, Type I AFP has an amphipathic, single ${\alpha}$-helix and has regularly spaced Thr-Ala residues which make direct interaction with oxygen atoms of ice crystals. Unlike Type I AFP, Type II and III AFP are compact globular proteins that contain a flat ice-binding patch on the surface. Type II and Type III AFP show a remarkable structural similarity with the sugar binding lectin protein and C-terminal domain of sialic acid synthase, respectively. Type IV is assumed to form a four-helix bundle which has sequence similarity with apolipoprotein. The results of our modeling suggest an ice-binding induced structural change of Type IV AFP. Insect AFP has ${\beta}$-helical structure with a regular array of Thr-X-Thr motif. Threonine residues of each Thr-X-Thr motif fit well into the ice crystal lattice and provide a good surface-surface complementarity. This review focuses on the structural characteristics and details of the ice-binding mechanism of antifreeze proteins.

• 대한수학교육학회지:수학교육학연구
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• 제17권3호
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• pp.253-270
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• 2007

18세기 프랑스의 수학자 A.C. Clairaut는 역사발생적 원리에 근거하여 기하 교재에 이어 대수 교재 <대수학 원론>을 집필하였다. 본 논문은 <대수학 원론>을 분석함으로써 대수 지도를 위해 Clairaut가 의도한 원리 및 구체적인 방식의 특징들을 고찰하고, 학교 수학에서 대수 영역의 교수-학습과 비교, 논의함으로써 적용 가능한 교수학적 시사점을 찾는 것을 목표로 한다. 이를 위해 <대수학 원론>의 구성 및 내용에 대해 개관하고 초보자의 정신에 자연스럽게 전개한다는 Clairaut의 의도에서 비롯된 대수 지도 원리의 여섯 가지 특징을 추출한다. 이 중에는 <기하학 원론>에서의 특징과 공통적인 것도 있고 대수라는 내용 영역상의 구별에서 비롯되는 독특한 것도 있다. 그리고 학교 수학의 대수 영역 중 특정 주제-방정식 세우기, 문자식의 계산과 문자의 부호, 곱셈의 부호 규칙, 이차방정식의 해법, 근과 계수와의 일반적 관계-와 관련하여 논의하고 시사점을 찾는다.

• Molecules and Cells
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• 제39권3호
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• pp.217-228
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• 2016

To generate a biobetter that has improved therapeutic activity, we constructed scFv libraries via random mutagenesis of several residues of CDR-H3 and -L3 of hu4D5. The scFv clones were isolated from the phage display libraries by stringent panning, and their antiproliferative activity against HER2-positive cancer cells was evaluated as a primary selection criterion. Consequently, we selected AH06 as a biobetter antibody that had a 7.2-fold increase in anti-proliferative activity ($IC_{50}$: 0.81 nM) against the gastric cancer cell line NCI-N87 and a 7.4-fold increase in binding affinity ($K_D$: 60 pM) to HER2 compared to hu4D5. The binding energy calculation and molecular modeling suggest that the substitution of residues of CDR-H3 to W98, F100c, A101 and L102 could stabilize binding of the antibody to HER2 and there could be direct hydrophobic interactions between the aromatic ring of W98 and the aliphatic group of I613 within HER2 domain IV as well as the heavy and light chain hydrophobic interactions by residues F100c, A101 and L102 of CDR-H3. Therefore, we speculate that two such interactions were exerted by the residues W98 and F100c. A101 and L102 may have a synergistic effect on the increase in the binding affinity to HER2. AH06 specifically binds to domain IV of HER2, and it decreased the phosphorylation level of HER2 and AKT. Above all, it highly increased the overall level of p27 compared to hu4D5 in the gastric cancer cell line NCIN82, suggesting that AH06 could potentially be a more efficient therapeutic agent than hu4D5.

• Molecules and Cells
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• 제40권9호
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• pp.655-666
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• 2017

We constructed a large $na{\ddot{i}}ve$ human Fab library ($3{\times}10^{10}$ colonies) from the lymphocytes of 809 human donors, assessed available diversities of the heavy-chain variable (VH) and ${\kappa}$ light-chain variable (VK) domain repertoires, and validated the library by selecting Fabs against 10 therapeutically relevant antigens by phage display. We obtained a database of unique 7,373 VH and 41,804 VK sequences by 454 pyrosequencing, and analyzed the repertoires. The distribution of VH and VK subfamilies and germline genes in our antibody repertoires slightly differed from those in earlier published natural antibody libraries. The frequency of somatic hypermutations (SHMs) in heavy-chain complementarity determining region (HCDR)1 and HCDR2 are higher compared with the natural IgM repertoire. Analysis of position-specific SHMs in CDRs indicates that asparagine, threonine, arginine, aspartate and phenylalanine are the most frequent non-germline residues on the antibody-antigen interface and are converted mostly from the germline residues, which are highly represented in germline SHM hotspots. The amino acid composition and length-dependent changes in amino acid frequencies of HCDR3 are similar to those in previous reports, except that frequencies of aspartate and phenylalanine are a little higher in our repertoire. Taken together, the results show that this antibody library shares common features of natural antibody repertoires and also has unique features. The antibody library will be useful in the generation of human antibodies against diverse antigens, and the information about the diversity of natural antibody repertoires will be valuable in the future design of synthetic human antibody libraries with high functional diversity.