• 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.

• 마이크로전자및패키징학회지
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• 제16권4호
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• pp.33-39
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• 2009

마스크리스 리소그래피(maskless lithography)에 응용하기 위한 마이크로렌즈 어레이(microlens array, MLA)가 석영의 습식 식각과 UV 접착제(UV adhesive)의 코팅을 바탕으로 개발되었다. 제작된 MLA의 초점거리는 ${\sim}45\;{\mu}m$ 정도였으며, 집광되는 광선의 초점은 ${\sim}1\;{\mu}m$로 측정되었다. MLA를 통과하며 초점을 맺은 빔(beam)의 크기 및 세기가 charge coupled device (CCD) 카메라와 빔 프로파일러(beam profiler)를 이용하여 각각 측정되었으며, 일정한 세기의 점들이 초점면에서 고르게 관찰되었다. 초점거리는 코팅된 UV 접착제의 두께에 따라 변화하였으며, UV 접착제의 두께가 두꺼울수록 짧아지는 경향을 보였다. 일반적인 마스크 얼라이너(mask aligner)를 이용한 MLA의 UV 포커싱(UV focusing)이 감광막(photoresist, PR) 상에서 실시되었으며, MLA를 통과한 빛이 감광막 위에 일정하게 집광되었다. 마스크 얼라이너와 MLA 사이의 거리 변화에 따라 감광막에 구현된 패턴 사이즈가 조절 되었다. 고온에서 오랜 시간이 지난 후에도 소자의 특성은 전혀 변함이 없었다.

• 한국광학회지
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• 제20권2호
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• pp.118-122
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• 2009

PET 필름 위에 LCD 백라이트의 프리즘 집광시트의 역할을 대체 할 수 있는 microlens array(MLA) 시트를 설계하고 제작하였다. Photoresist thermal reflow 공정으로 두께 $100{\mu}m$ PET 필름 위에 MLA를 제작하였고, 노광 시간과 reflow의 온도, 시간 등의 변수에 따른 MLA의 형상 변화를 측정하였다.

• Toxicological Research
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• 제18권2호
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• pp.129-138
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• 2002

The mouse lymphoma assay (MLA) has been recently validated as a sensitive and specific test system to determine the genotoxic potential for a chemical. The objective of this study is to evaluate the utility of MLA for detecting mutagens. Especially, to compare MLA with the in vitro chromosomal aberration test (CA), we performed MLA using the microwell method with three chemicals (hydroxyurea, theophylline and amino acid copper complex), which were reportedly positive in the CA. In cell treated with hydroxyurea, anti-neoplastic agent that blocks DNA replication, evidence of a positive response was obtained without S9 mix for 4 h and 24 h. In addition, analysis of colony size distribution at concentration that gave an elevated mutant fraction showed that hydroxyurea induced a high proportion of small type colonies, indicating that hydroxyurea-induced mutation is associated with large chromosomal deletion. Conversely, negative MLA result was obtained for theophylline, which was wed as central nervous system stimulator. Although theophylline increased the mutant frequency at concentration of 1250 $\mu\textrm{g}$/$\textrm{m}{\ell}$ with S9 mix for 4 h, a concentration-related increase in mutant frequency was not observed. The MLA result of amino acid copper complex was considered equivocal because the positive result was obtained at concentration showing 10% or less RS or RTG. Thus, among 3 CA-positive chemicals, positive MLA result was obtained for one. The other two chemicals were negative and equivocal. However MLA, which evaluates mutagenic potential of chemicals through colony formation by cell grouth, may provide a higher predictivity of carcinogenesis than CA.

• 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.

• Journal of the Optical Society of Korea
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• 제18권5호
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• pp.538-545
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• 2014

Microlens array (MLA) films have been used as brightness-enhancement components in many illumination systems, such as a backlight, which should meet the industrial needs of low cost and high brightness performance. A hexagonally-arranged MLA (HA-MLA) was chosen due to its high filling factor, which was a prerequisite for achieving high brightness-enhancement capability. The moir$\acute{e}$ fringes produced in a film stack composed of two HA-MLA were investigated, under four different lens configurations, by optical simulation. It was found that randomizing the lens configuration, while keeping the filling factor high, was effective way to develop high-gain MLA films for backlight applications.

• 한국전문물리치료학회지
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• 제24권4호
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• pp.46-53
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• 2017

Background: The MLA is supported by both the abductor hallucis (ABH) and the extrinsic muscles. Insufficient muscular support may lower the MLA when the body's weight is applied to the foot. The short foot exercise (SFE) is effective in increasing the height of the MLA for people with flat feet. Most of the research related to the SFE has simply evaluated the efficiency of the exercise using enhanced ABH electromyography (EMG) activation. Since the tibialis anterior (TA), peroneus longus (PER), and ABH are all involved in supporting the MLA, a new experiment design examining the EMG of the selected muscles during SFE should be applied to clarify its effect. Objects: Therefore, this study aimed to clarify the effect of the SFE in different ankle position on the MLA angle and the activation of both the intrinsic and extrinsic muscles and to determine the optimal position. Methods: 20 healthy subjects and 12 subjects with flat feet were recruited from Yonsei University. The surface EMG and camera were used to collect muscle activation amplitude of TA, PER, and ABH and to capture the image of MLA angle during SFE. The subjects performed the SFE while sitting in three different ankle positions-neutral (N), dorsiflexion (DF) at 30 degrees, and plantar flexion (PF) at 30 degrees. Results: ABH EMG amplitudes were significantly greater in N and DF than in PF (p<.05). Muscle activation ratio of TA to ABH was the lowest in PF (p<.05). MLA angle in both groups significantly decreased in PF (p<.01). The TA and ABH was activated at the highest level in DF. However, in PF, subjects significantly activated the ABH and PER with relatively low activation of TA. Conclusion: Therefore, researchers need to discuss which SFE condition most effectively use the arch support muscle for flat foot.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.199-199
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• 2009

Recently, polymeric microlens arrays have become important elements in many applications. Microlens arrays have been used to enhance luminance efficiency and luminance power efficiency of light-emitting diodes (LEDs) and organic LEDs. Many processes for fabrication of microlens array are studied. Though the MLA has been fabricated by electroformed mold, LIGA process and reflow method, these methods were required masks, multiple process steps and post processing. In this paper, we proposed rapid and direct UV laser direct fabrication process using colorless liquid photopolymer, NOA60 for polarization activated microlens. The microlens arrays are formed on the NOA60 on glass, after the focused laser energy was irradiated to the material. The diameter of MLA was varied from 42 to 88 ${\mu}m$, and the height from 0.9 to 1.6 ${\mu}m$. The MLA fabricated using NOA60 shows more then 85% transmittance as well as good hardness for optical module.