• YAKHAK HOEJI
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• v.39 no.3
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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.

• YAKHAK HOEJI
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• v.38 no.4
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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.

• YAKHAK HOEJI
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• v.39 no.3
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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.

• Communications of Mathematical Education
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• v.37 no.2
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• pp.183-197
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• 2023

Mathematical listening ability(MLA) refers to the capability to listen to speech languages that contain mathematical principles and concepts and understand their meanings, distinguishing it from daily life and listening in other subject classes. In this study, I investigated 834 elementary school students' MLA adapting a MLA survey items. Through the statistical analysis results of the survey, I confirmed that students' MLA had a significant correlation with gender, grade, and school location. Female students' MLA was statistically significantly higher than that of male students. MLA increased with grade and then decreased again in 6th grade. In addition, students' MLA was statistically significant differences according to the location of the school. The results of this study might be used as the basis for follow-up research and development of teaching and learning materials related to MLA.

• Communications of Mathematical Education
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• v.37 no.1
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• pp.1-19
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• 2023

Mathematics Listening Ability(MLA) refers to the ability to listen to and grasp the meaning of speech language containing mathematical concepts and principles, distinguishing it from daily life and listening in other subject classes. According to literature, MLA might be divided into six types. Among them, interpretation, discovering, evaluating, and evaluation may indicate an attitude that correctly listens to the meaning of the language used in mathematics classes. On the other hand, selective, pretend, and ignore are types of listening attitudes that are not appropriate. Based on the statistical analysis of 834 3rd to 6th graders and a total of 44 homeroom teachers I developed a MLA survey items for elementary school students. In this study, principal component analysis was conducted to verify reliability in the development of survey items, and expert review and correlation analysis of survey results were conducted to verify validity. In addition, the validity was verified by statistically analyzing the survey results of students and their homeroom teachers. Based on literature and statistical analysis, I developed a MLA Survey items(for students) consisting of 25 questions and a mathematical resolution measurement tool(for teachers) consisting of 26 questions.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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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.

• Proceedings of the Korean Society of Laser Processing Conference
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• 2005.11a
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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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• v.3 no.1
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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.