• 약학회지
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• 제39권3호
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• pp.243-251
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• 1995

Three new lectins, MLA-I, MLA-II and MLA-III, have been isolatedand purified from the hemolymph of Meretrix lusoria and reported previously. Biophysicochemical characteristics were investigated with these three MLA lectins. The MLA lectins agglutinated human erythrocytes non specifically and proved as D-galactose group carbohydrate specific. Molecular weight of ML.A-I. II and III were estimated to be 330, 500 and 310KD, respectively, by gel filtration on Sepharose CL-6B column. On SDS-polyacrylamide gel electrophoresis, ML.A-I was dissociated into a single subunit of 42KD, MLA-II was into the twelve subunits of 46, 32, 30, 28, 25, 23. 22, 20. 19, 16, 15, and 14KD, and MLA-III was into the two subunits of 72 and 44KD. The pl of MLA-I, II, III were 4.0. 4.9 and 5.0. Amino acid analysis revealed a high contents of acidic and hydroxy amino acids, and a paucity of sulfur containing amino acids. Proline was not contained in MLA-II.

• 약학회지
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• 제38권4호
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• pp.394-400
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• 1994

As a previous step for the development of immunostimulating substance from marine natural products the two new lectins, MLA-II and MLA-III, have been isolated and purified from the hemolymph of Meretrix lusoria in addition to the previously reported MLA-I. The new lectins molecules were characterized as pure by electrophoretic studies.

• 약학회지
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• 제39권3호
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• pp.252-259
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• 1995

Isolation, purification and characterization of biophysicochemical properties of the three new lectins, MLA-I, MLA-II, MLA-III from the hemolymph of Meretrix lusoria have been reported previously. A series of immunochemical studies were investigated in this work. The three lectins were revealed as having partial identity each other by immunodiffusim and immunoelectrophoresis. These results suggest that MLA lectins are isolectins having similar biophysicochemical properties. Particularly, MLA-I proved to be a potent mitogen for murine splenic as well as human peripheral lymphocytes, and the optimum mitogenic dose were 62.5 and 1.95 $\mu\textrm{g}$/ml, respectively.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제37권2호
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• pp.183-197
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• 2023

수학 청해력이란 수학적 원리와 개념이 내포된 음성 언어를 듣고 그 의미를 파악하는 능력을 지칭한다. 수학 청해력은 타 교과 수업, 일상생활 속 듣기와 구분된다. 본 연구에서는 수학 청해력 측정 도구를 활용하여 초등학교 학생 834명의 수학 청해력 실태를 조사하였다. 설문조사의 통계 분석 결과를 통해 학생들의 수학 청해력은 성별, 학년, 학교의 위치와 통계적으로 유의미한 상관관계가 있음을 확인하였다. 여학생의 수학 청해력이 남학생보다 높으며, 수학 청해력은 학년에 따라 증가하다가 6학년에서 다시 감소하는 것을 알 수 있었다. 또한 학교의 위치에 따라 학생들의 수학 청해력이 유의미한 차이를 보였다. 본 연구의 결과는 수학 청해력 관련 후속 연구, 교수·학습 자료 개발의 토대로 활용될 수 있다.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제37권1호
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• pp.1-19
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• 2023

수학 청해력이란 수학적 개념과 원리가 포함된 음성 언어를 듣고 그 의미를 파악하는 능력을 의미하며 일상생활 및 타 교과 수업에서의 듣기와 구분할 수 있다. 선행연구에 따르면 수학 청해력은 여섯 가지 유형으로 구분할 수 있다. 그 중 해석하며 듣기, 발견하며 듣기, 평가하며 듣기는 수학 수업에서 바람직한 듣기 태도를 나타낸다. 반면 선택적으로 듣기, 듣는 척하기, 무시하기는 적절하지 않은 듣기 태도 유형이다. 본 연구에서는 수학 청해력의 여섯 가지 유형을 기반으로 초등학교 3~6학년 학생들 834명과 그들의 담임 교사 총 44명을 대상으로 한 설문의 통계적 분석을 근거로 초등학교 학생을 대상으로 하는 수학 청해력 측정 도구를 교사용, 학생용으로 나누어 개발하였다. 측정 도구 개발 과정에서 신뢰도 검증을 위해 주성분 분석(Principal Component Analysis)을, 타당도 검증을 위해 전문가 검토 및 교사용과 학생용 측정 도구 응답 결과의 상관관계 분석을 진행하였다. 또한 학생들과 그 담임 교사의 설문 결과를 통계적으로 분석하여 추가 타당도 검증을 하였다. 선행연구 및 통계 자료 분석을 토대로 본 연구에서는 25개의 문항으로 구성된 수학 청해력 측정 도구(학생용), 26개의 문항으로 이루어진 수학 청해력 측정 도구(교사용)를 개발 하였다.

• Bulletin of the Korean Chemical Society
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• 제16권6호
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• pp.484-489
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• 1995

The synthesis of new bismuth-barium containing members of layered cuprates with 2201 type structure was reported. By solution calorimetry the formation enthalpies for Bi2MLaCuO6.5 (M=Ba, Ba0.5Sr0.5, Sr) were obtained. Crucial influence of partial oxygen pressure and size of lanthanoid on stability of layered cuprates was shown. Electronic states of variable valence atoms were studied by voltammetry of solids.

• 한국레이저가공학회:학술대회논문집
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• 한국레이저가공학회 2005년도 추계학술발표대회 논문집
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• pp.37-41
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• 2005

When screen size of the Flat Panel Display (FPD) becomes larger, the traditional photo-lithography using photomasks and UV lamps might not be possible to make patterns on Photo Resist (PR) material due to limitation of the mask size. Though the maskless photo-lithography using UV lasers and scanners had been developed to implement large screen display, it was very slow to apply the process for mass-production systems. The laser exposure system using 405 nm semi-conductor lasers and Digital Micromirror Devices (DMD) has been developed to overcome above-mentioned problems and make more than 100 inches FPD devices. It makes very fine patterns for full HD display and exposes them very fast. The optical engines which contain DMD, Micro Lens Array (MLA) and projection lenses are designed for 10 to 50 ${\mu}m$ bitmap pattern resolutions. The test patterns for LCD and PDP displays are exposed on PR and Dry Film Resists (DFR) which are coated or laminated on some specific substrates and developed. The fabricated edges of the sample patterns are well-defined and the results are satisfied with tight manufacturing requirements.

• Molecular & Cellular Toxicology
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• 제3권1호
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• pp.23-30
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• 2007

The effects of high energy short wave solar radiation on human skin have received much publicity as the major cause of accelerated skin ageing and of skin cancers. To meet public demand, the cosmetic industry has developed sun protection factor products, which contain a variety of so-called "UV filters", among others benzophenone (BP) and its metabolites are the widely used UV filters. UV filters are also used to prevent UV light from damaging scents and colors in a variety of cosmetics products and to protect of plastic products against light-induced degradation. There are many variants of BP in use. In this respect, to regulate and to evaluate the hazardous effect of BP-type UV filters will be important to environment and human health. The genotoxicity of 7 BP-type UV filters was evaluated in L5178Y $(tk^{+/-})$ mouse lymphoma cells in vitro. BP, benzhydrol, 4-hydroxybenzophenone 2-hydroxy-4-methoxybenzophenone and 2, 4-dihydroxybenzophenone did not induce significant mutation frequencies both in the presence and absence of metabolic activation system. 2, 2'-Dihydroxy-4-methoxybenzophenone appeared the positive results at the highest dose, i.e. 120.4 ${\mu}g/mL$ only in the absence of metabolic activation system. And also, 2, 3, 4-trihydroxybenzophenone revealed a significant increase of mutation frequencies in the range of 138.1-207.2 ${\mu}g/mL$ in the absence of metabolic activation system and 118.3-354.8 ${\mu}g/mL$ in the presence of metabolic activation system. Through the results of MLA with 7 BP-type UV filters in L5178Y cells in vitro, we may provide the important clues on the genotoxic potentials of these BP-type UV filters.