• Journal of Mushroom
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• v.12 no.2
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• pp.96-106
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• 2014

The primary objective of the present study is the characterization of the somatic hybrids of dikaryon-monokaryon (di-mono) crosses in mushroom breeding. We employed this technique for developing superior strains from Pleurotus ostreatus strains with 48 intraspecific hybrids of 12 combinations between six P. ostreatus strains and one P. florida strain. The results on the experiments of hybridization rate, nuclear DNA patterns, and colors and morphology of fruit-bodies, are presented. In di-mono crosses, somatic hybrids among Pleurotus strains showed 100% of crossability as seen in those between P. ostreatus and P. florida strains indicating that the nuclei of a dikaryon is inferred to be migrated to a recipient. 87.5% of the somatic hybrids among Pleurotus strains were similar to the donor dikaryons, and 12.5% of the somatic hybrids presented DNA patterns of both parents. In 16.6% of di-mono crosses between P. ostreatus and P. florida, the nuclear DNA patterns of all hybrids showed the same or similar patterns compared to the donor dikaryons. 70.9% of the hybrids between P. ostreatus and P. ostreatus were similar to the donor dikaryons and 12.5% of them presented the DNA patterns of both parents. 79.2% of fruiting body morphology of the hybrids among Pleurotus strains were similar to the dikaryons and 20.8% of them were similar to both parents. Interestingly, the morphology of all dikaryons were dissimilar each other. All hybrid strains between dikaryon P. florida and monokaryon P. ostreatus showed the fruiting body of which colors were similar to those of the dikaryon, while the hybrids between dikaryon P. ostreatus and monokaryon P. florida were showed the combined colors of both parents. Therefore, the fruiting body color of P. florida tends to be generally dominant. In conclusion, the present study provides a way to find out and suggest superior hybrid strains using the nuclear DNA patterns of hybrids between Pleurotus strains as well as the characteristics of their fruiting bodies. The advantages of the di-mono crossing are needs to be fully utilized in mushroom breeding because it is an ideal way to develop the superior strains of Pleurotus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1025-1035
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• 2014

This study assessed the effect of immobilized lipase on weak base styrene resin using polyethyleneimine (PEI) with cross-linking. Two procedures were used in this study. The first one, "mono-layer" lipase immobilization, involves washing PEI after adsorption. The second procedure, "multi-layer" lipase immobilization, has no washing before the cross-linking step. Treverlite XS-100200 (weak base styrene resin) was immersed with PEI solution (2.2 mg/mL). Lipase AH (from Burkholderia cepacia) was adsorbed onto the support coated with PEI before cross-linking with glutaraldehyde. Structured lipid was synthesized by immobilized lipase-catalyzed interesterification using canola oil, palmitic ethyl ester (PEE), and stearic ethyl ester (StEE). Total fatty acid contents of triacylglycerol (TAG) in structured lipids were analyzed to investigate activity, properties, and reusability of immobilized lipases. Activities of immobilized lipases on the multi-layer and mono-layer increased at a high concentration (8 mg/mL) of lipase solution used for immobilization. The results show that immobilized lipase with the mono-layer method at pH 8.0 on resin had the highest total saturated fatty acid content (26.17 area%). Activity of immobilized lipase with the multi-layer method at pH 7.5 on support was lower than that of the mono-layer, but total saturated fatty acid content was 16.79 area% higher than that of lipase AH (15.01 area%).

• Microbiology and Biotechnology Letters
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• v.37 no.1
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• pp.75-79
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• 2009

In this study, we polymerized new materials for soft contact lens using HEMA (2-hydroxyethyl methacrylate) which is the based-monomer of soft contact lens, EGDMA (ethylene glycol dimethacrylate) as cross linkage agent, and the new additives of monoester or di-ester derived from itaconic acid commercially produced by the fermentation of Asp. itaconicus. New polymer materials for soft contact lens were synthesized with the mixture of HEMA and mono- or diester at different ratios and presented to a good water content and oxygen transmissibility (Dk/L) values. In case of polymerization with HEMA and mono-ester (15%), the water content and oxygen transmissibility of contact lens were found to be good values at 57.6% and 28.5 Dk respectively. The mixture of HEMA and mono-ester is more excellent than HEMA/di-ester in the water content and oxygen transmissibility. The toxicity of new contact lens materials were confirmed in the fibroblast L-929 cell line using a agar overlay test and a growth inhibition test with the extract solution of contact lens.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.338-343
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• 2003

Various factors, such as the adsorption pH, adjuvant dose, and adjuvant age, which affect the adsorption degree and immunogenicity of an antigen, were investigated. In addition, the effect of pH, antigen content, and adjuvant content on immunogenicity was also studied through animal experiments. Within the ranges studied, a low pH for adsorption, freshly preformed gel, and low pH formulation for the combined DTwP-HepB vaccine were preferrable for the adsorption of the antigens. In addition, a higher DT content was found to have a positive effect on the HBsAg immunogenicity in the combined vaccine. Accordingly, considering the factors affecting the adsorption rate and immunogenicity of the antigens, a novel DTwP-HepB vaccine (40 Lf/ml of diphtheria toxoid, 15 Lf/ml of tetanus toxoid, 20 OU/ml of detoxified whole cell pertussis, $24\;\mu\textrm{g}$ of HBsAg, $24\;\mu\textrm{g}\;Al/ml\;of \;Al(OH)_3\;gel,\;776\;\mu\textrm{g}\; Al/ml\;of\;AIPO_4\;gel$, and pH 7.1) was developed, whose immunogenicity was comparable to the case of administrating, separately and simultaneously, a combined DTwP vaccine (40 Lf/ml of diphtheria toxoid, 15 Lf/ml of tetanus toxoid, 20 OU/ml of detoxified whole cell pertussis, $300\;\mu\textrm{g}\;Al/ml\;of\; AIPO_4\;gel$, and pH 7.1) and mono HepB vaccine [$Hepavax^{\circledR},\;24\;\mu\textrm{g}/ml$ of HBsAg and $500\;\mu\textrm{g}\;Al/ml\;of\;Al(OH)_3\;gel$], which satisfies the potency criteria of the K-FDA for a combined DTwP vaccine and mono HepB vaccine.

• Structural Engineering and Mechanics
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• v.52 no.4
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• pp.787-813
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• 2014

Starting with Hamilton's variational principle, the governing field equations for the steady state response of thin-walled beams under harmonic forces are derived. The formulation captures shear deformation effects due to bending and warping, translational and rotary inertia effects and as well as torsional flexural coupling effects due to the cross section mono-symmetry. The equations of motion consist of four coupled differential equations in the unknown displacement field variables. A general closed form solution is then developed for the coupled system of equations. The solution is subsequently used to develop a family of shape functions which exactly satisfy the homogeneous form of the governing field equations. A super-convergent finite element is then formulated based on the exact shape functions. Key features of the element developed include its ability to (a) isolate the steady state response component of the response to make the solution amenable to fatigue design, (b) capture coupling effects arising as a result of section mono-symmetry, (c) eliminate spatial discretization arising in commonly used finite elements, (d) avoiding shear locking phenomena, and (e) eliminate the need for time discretization. The results based on the present solution are found to be in excellent agreement with those based on finite element solutions at a small fraction of the computational and modelling cost involved.

• Macromolecular Research
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• v.15 no.3
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• pp.244-255
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• 2007

Nucleation is the most sensitive stage in the preparation of highly cross-linked, monodisperse microspheres by dispersion polymerization, since the addition of a small amount of cross-linker results in particle deformation and coagulation. To overcome these problems, $5\;{\mu}m$ poly(methyl methacrylate) seed particles prepared by dispersion polymerization were used in the preparation of mono disperse, cross-linked PMMA particles containing up to 7 wt% divinylbenzene by seeded batch dispersion polymerization. Spherical particles with a narrow size distribution containing up to 8 wt% of EGDMA were prepared by seeded multi-batch dispersion polymerization processes. These particles were identified by scanning electron microscopy and DSC.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.179-183
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• 2003

• Steel and Composite Structures
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• v.18 no.3
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• pp.603-621
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• 2015

In this study, theoretical models and design procedures of the behavior of thin-walled simply supported steel beams with an open cross section under a large torsional effect are presented. I-sections were chosen as the cross section types. Firstly, the widely used differential equations for the lateral buckling for the pure bending moment effect in a beam element were adopted for the various moment distributions along the span of the beam. This solution was obtained for both mono-symmetric and bisymmetric sections. The buckling loads were then obtained by using the energy method. When using the energy method to solve the problem, it is possible to locate the load not only on the shear center but also at several points of the section depth. Buckling loads were obtained for six different load types. Results obtained for different load and cross section types were checked with ABAQUS software and compared with several standard rules.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.3
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• pp.169-177
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• 2000

In machining screws which are important members in mono pumps or progressive cavity pumps CNC turning center with 3 axes is usually used. This sort of screw machining requires large amount of CL data points and rotational tools are used in machining. When working out the CL data points consideration of possible tool interference is important in order to avoid undercut. This paper describes the checking methods of tool interference in the screw machining on the CNC turning center. First of all a specific shape of a screw cross-section that could commonly be applied to all screws was chosen and then possible tool interference associated with that shape was identified. Checking method was mathematically developed and verified. This checking method will be utilized in the CAM system developed by the authors for screw machining on the 3-axis CNC turning center.

• Structural Engineering and Mechanics
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• v.33 no.4
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• pp.447-484
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• 2009

The spatially coupled buckling, in-plane, and lateral bucking analyses of thin-walled Timoshenko curved beam with non-symmetric, double-, and mono-symmetric cross-sections resting on elastic foundation are performed based on series solutions. The stiffness matrices are derived rigorously using the homogeneous form of the simultaneous ordinary differential equations. The present beam formulation includes the mechanical characteristics such as the non-symmetric cross-section, the thickness-curvature effect, the shear effects due to bending and restrained warping, the second-order terms of semitangential rotation, the Wagner effect, and the foundation effects. The equilibrium equations and force-deformation relationships are derived from the energy principle and expressions for displacement parameters are derived based on power series expansions of displacement components. Finally the element stiffness matrix is determined using force-deformation relationships. In order to verify the accuracy and validity of this study, the numerical solutions by the proposed method are presented and compared with the finite element solutions using the classical isoparametric curved beam elements and other researchers' analytical solutions.