• KSBB Journal
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• v.18 no.4
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• pp.255-260
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• 2003

In vivo bioassays for biological medicines have been considered final resort to unequivocally assess the biological activities for them because there are some cases in which the biological activities obtained from in vivo bioassay and in vitro bioassay quite differ each other. The in vivo biological activity of EPO depends on its sialic acid contents which confer microheterogeneity-isoforms to this protein. We have devise a method which consists of a in vitro bioassay using BaF3 cell line and a capillary zone electrophoresis (CZE) for the measurement of the EPO isoform distribution. The biological activity of EPO obtained using in vitro bioassay with BaF3 cell line showed good correlation (C.V.(％) 7.34, 5.85, 8,16, 8.08, 8.8) to EPO content measured either spectrophotometric assay (A280 0.1 ％ ＝0.743) or radio immunoassay. The assay validation results of in vitro bioassay with 3 lot of in house EPO showed good results to EPO content measured either in vivo assay or radio immunoassay. and also showed good results the robustness of our method in terms of precision, accuracy, repeatability. The isoform distribution for EPO-BRP (1 : 1 mixture of epoetin-${\alpha}$ and epoetin-${\beta}$, European Pharmacopoeia) by CZE method resulted in isoform 2 through isoform 8. The major peaks in electrophoregram were composed of isoform 3 through 7. Our recombinant EPO (epoetin-${\alpha}$) having equivalent in vivo biological activity showed the isoform distribution of isoform 3 through 9. The major peaks consisted of isoform 4 through 8. The peak area of isoform 4 was always smaller than that of isoform 5. The preparations of recombinant epoetin-${\alpha}$ with lower in vivo biological activity than EPO-BRP showed the isoform 2 through 8 in their electrophoregrams whose major peaks consisted of the isoform 3 through 7. The peak area of isoform 4 was larger than that of isoform 5.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.183-194
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• 2016

This experiment was conducted to establish an official determination method to measure fluazinam residue in horticultural crops for import and export using GC-ECD/MS. Fluazinam residue was extracted with acetone from fresh samples of four representative horticultural products, the vegetable crops green pepper and kimchi cabbage, and the fruit crops mandarin and apple. The acetone extract was diluted with saline water and n -hexane partitioning was used to recover fluazinam from the aqueous phase. Florisil column chromatography was additionally employed for final purification of the extract. Fluazinam was separated and quantitated by GC with ECD using a DB-17 capillary column. The horticultural crops were fortified with three different concentrations of fluazinam. Mean recoveries ranged from 82.5% to 99.9% in the four crops. The coefficients of variation were less than 10.0%. The quantitative limit of fluazinam detection was $0.004mg{\cdot}kg^{-1}$ in the four crop samples. GC/MS with selected-ion monitoring was also used to confirm the suspected residue. This analytical method was reproducible and sensitive enough to measure the residue of fluazinam in horticultural commodities for import and export.

• Journal of the Korean Society of Tobacco Science
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• v.3 no.1
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• pp.11-19
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• 1981

Essential oil components were isolated both from Oriental and- Korean using a modified distillation/solvent extraction method. The essential oils were then analyzed by high-resolution glass capillary gas chromatography, to give characteristic GC profile from each tobacco. Varietal differences were detected from the quantitative comparison of the GC data.

• Journal of the Korean Society of Tobacco Science
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• v.3 no.1
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• pp.1-10
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• 1981

Volatile compounds in the headspace vapors of five aromatic tobacco varieties have been examined us ins the polymer adsorption method and high- resolution glass capillary gas chromatography. The gas chromatographic profiles thus obtained were compared, and the aroma composition was found to be characteristic of each tobacco sample with significant differences in the concentrations of major components.

• Journal of the Korean Chemical Society
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• v.15 no.3
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• pp.109-116
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• 1971

The mechanical degradation of poly (${\alpha}$-methyl styrene) in several mixed solvents (toluene-n-butyl alcohol, toluene-sec-butyl alcohol, toluene-kerosene, toluene-methyl ethyl ketone), from $1^{\circ}C to $45^{\circ}C$, was studied using the capillary flow method. The velocity constant of scission reaction (k) and the limited degree of polymerization (g) were compared at the same value of [${\eta}$] at each temperatures. As results, mechanical degradation of polymer in dilute mixed solutions is affected by composition of solvents around the polymer chains.

• The Korean Journal of Cytopathology
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• v.1 no.1
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• pp.36-42
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• 1990

The fluoroscopy-guided fine needle aspiration biopsy has been gaining widespread acceptance as a rapid and effective method to make a pre-operative diagnosis of mediastinal tumors including thymoma, malignant lymphoma, and metastatic carcinoma. Although thymoma is a most common tumor of the superior mediastinum, most cytopathologists are not experted in cytologic diagnosis of this tumor because of limited experience. In order to define the diagnostic cytologic features of thymoma, we have retrospectively reviewed imprinting smears and corresponding tissue sections from four cases of this tumor. All cases revealed an apparent biphasic pattern of epithelial cell clusters and lymphocytes with occasional branching capillary fronds extending from three dimensional epithelial cell clusters. Epithelial cell clusters predominated in one case and lymphocytes in two cases. Mixed epithelial cell and lymphocyte type represented in one of four cases. In the lymphocyte predominant type, the presence of epithelial cell clusters and small mature lymphocytes are helpful features to differentiate from a malignant lymphoma.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.369-369
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• 2012

The present work deals with selective deposition of copper on fluoropolymers patterned silicon (111) surfaces. The pattern of fluoropolymer was fabricated by nanoimprint lithography (NIL) and plasma reactive ion etching (RIE) was used to remove the residuals layers. Copper was electrochemically deposited in bare Si regions which were not covered with fluoropolymers. The patterns of fluoropolymers and copper have been investigated by scanning electron microscopy (SEM). In this work, we used two deposition methods. One is galvanic displacement method and another is electrodeposition. Selective deposition works in both cases and it shows applicability to other materials. By optimization of the deposition conditions can be achieved therefore this process represents a simple approach for a direct high resolution patterning of silicon surfaces.

• Architectural research
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• v.12 no.2
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• pp.93-98
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• 2010

This paper describes a numerical method for estimating the elastic moduli of cement paste. The cement paste is modeled as a unit cell which consists of three components: the unhydrated cement grain, the gel, and the capillary pore. In the unit cell, the volume fractions of the constituents are quantified using a single kinetic function calculating the degree of hydration. The elastic moduli of cement paste are calculated from the total displacements of constituents when a uniform pressure is applied to the gel contact area. The cement paste is assumed to be a homogenous isotropic matrix. Numerical simulations were conducted through the finite element analysis of the three-dimensional periodic unit cell. The model predictions are compared with experimental results. The predicted trends are in good agreement with experimental observations. This approach and some of the results might also be relevant for other technical applications.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.603-607
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• 2002

Recently, the need leer transporting and manipulating minute amount of fluids in microscale channels (so-called micro-fluidics) has been increasing, especially in biotechnology and biochemical processing. This work demonstrates that the mechano-chemical process which consists of mechanical abrasive action combined with chemical process can be used to fabricate micro-fluidic channels more rapidly and cost effectively than other methods. In this work, capillary filling of fluids in micro-channels was investigated by theoretical approaches and experiments. From the experimental results, it is expected that a complex micro-fluidic system can be fabricated using the micro- fabrication technique and microsystem packaging method described in this work.

• Korean Journal of Animal Reproduction
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• v.16 no.4
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• pp.335-340
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• 1993

The development of efficient method for the production of transgenic mice has been investigated in our laboratory. This study was conducted to develop the artificial insemination in the mouse. Spermatozoa were collected from the cauda epididymis of ICR males(age:12~15 weeks, Body weight : 30g) and artificially inseminated into the intrauterine via cervix of hormone-primed ICR females(age: 6~8 weeks, body weight: 25g) using the capillary tube, 200~300 $\mu$m in inner diameter. The effect of concentration of sperm(80$\times$104, 40$\times$104, 20$\times$104, 10$\times$104, 5$\times$104, 3$\times$104, 1$\times$104/20${mu}ell$. The artificial insemination was succeeded but fertilization rate was very low(5~15%) compared to the natural mating and 59 normal youngs born from 60 females. Therefore, our findings suggest that it is possible to produce the great number of mice from the same orgin of male by artificial inseminatin. However, the lower pregnancy rate has to be solved to used broadly the artificial insemination in mouse.