• Composites Research
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• v.15 no.3
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• pp.1-10
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• 2002

The effect of size of SiC particles and additive Mg content on the mechanical properties and wear characteristics were investigated for the SiCp/AC8A composites fabricated by pressureless infiltration process. Results showed that the hardness and the bending strength increased with decreasing the size of SiC particle. By increasing the Mg content the hardness of SiCp/AC8A composites increased due to the hard reaction products, however the bending strength decreased by formation of coarse precipitates and high porosity level. The SiCp/AC8A composites exhibited about 6 times higher wear resistance compared with AC8A alloy at high sliding velocity and as increasing the particle size, wear resistance was improved. The major wear mechanical of SiCp/AC8A composites exhibited the abrasive wear at low to high sliding velocity whereas AC8A alloy showed adhesive and melt wear at high sliding velocity.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.403-409
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• 1995

A growth experiment was conducted to evaluate the nutritivie values of supplemental lysine and methionine in broiler chicks. Two types of L-lysine, liquid and powder type, and DL-methionine were added to the diets at different levels of dietary protein with two growth phases, 0-3 weeks and 4-6 weeks named starter and grower, respectively. Six hundred seventy two chicks were allotted in 14 treatments; 3 controls by dietary CP level (starter-grower) with CP 23-21%, CP 21-19% and CP 20-18, 8 groups of liquid and powder lysine supplementation of 0.1, 0.2, 0.3 and 0.4%, and 3 groups of lysine and methionine supplementation. Body weight, feed intake, and excreta were measured and analyzed to determine growth performance, amino acid digestibilities, and the quantity of excreted nitrogen in feces. Chicks fed CP 23-20 with 3,200 ME kcal showed significantly better growth performance than those fed CP 21-18 for 6 weeks. The supplementation of 0.2% of either type of lysine to CP 21-19 diet improved weight gain and feed efficiecy to the extent that CP 23-21 diet was fed. Physical type of lysine did not affect chick's growth and amino acid digestibilities of the diets. The level of CP in the diet significantly affected nitrogen excretion in feces. Supplementation of lysine and methionine to CP 21-18 diet reduced fecal nitrogen by 10% compared to CP 23-21 diet. It was confirmed that 0.2% of supplemental lysine to the broiler diet spared the dietary protein by 3%, and also reduced nitrogen excretion in feces by 10%.

• Plant Biotechnology Reports
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• v.2 no.1
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• pp.75-85
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• 2008

Prune dwarf virus (PDV) is an Ilarvirus systemically infecting almond trees and other Prunus species and spreading through pollen, among other means. We have studied strategies based on coat protein (cp) gene to block PDV replication in host plant cells. A Portuguese isolate of PDV was obtained from infected almond leaves and used to produce the cDNA of the cp gene. Various constructs were prepared based on this sequence, aiming for the transgenic expression of the original or modified PDV coat protein (cpPDVSense and cpPDVMutated) or for the expression of cpPDV RNA (cpPDVAntisense and cpPDVwithout start codon). All constructs were tested in a PDV host model, Nicotiana benthamiana, and extensive molecular characterization and controlled infections were performed on transformants and their progenies. Transgenic plants expressing the coat protein RNA were able to block the proliferation of a PDV isolate sharing only 91% homology with the isolate used for cpPDV cloning, as evaluated by DAS-ELISA on newly developed leaves. With cp expression, the blockage of PDV proliferation in newly developed leaves was only achieved with the construct cpPDV Mutated, where the coat protein has a substitution in the 14th aa residue, with arginine replaced by alanine. This result points to a possible role of the mutated amino acid in the virus ability to replicate and proliferate. This work reveals the possibility of achieving protection against PDV through either coat protein RNA or mutated cp sequence.

• Bulletin of the Korean Chemical Society
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• v.14 no.5
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• pp.549-554
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• 1993

The CO substitution reactions in the complex, $Cp^*(C_5H_7)$CrCO with $PR_3(PR_3=PMePh_2,\;P(OCH_3)_3,\;PMe_2Ph)$ were investigated spectrophotometrically at various temperatures. For the reaction rates, it was suggested that the CO substitution reaction took place by first-order (dissociative) pathway. Activation parameters in decaline are ${\Delta}H^{\neq}= 21.99{\pm}2.4$ kcal/mol, ${\Delta}S^{\neq}= 8.9{\pm}7.1$ cal/mol·k. Unusually low value of ${\Delta}S^{\neq}$, suggested an ${\eta}^5-S{\to}\;{\eta}^5$-U conversion of the pentadienyl ligand. At various temperature, the rates of reaction for the Cp(pdl)CrCO complexes increase in the order $Cp^*(C_5H_7)$-CrCO < Cp$(C_5H_7)$CrCO < Cp(2,4-$C_5H_{11}$)CrCO, which can be attributed to the usual steric acceration or electronic influence for the ligand substitution of metal complexes. This suggestion was confirmed by the extended-Huckel molecular orbital (EHMO) calculations, which revealed that the energy of $[Cp^*(U-C_5H_7)Cr]^{\neq}$ transition state is about 4.93 kcal/mol lower than that of [Cp(S-$C_5H_7)Cr]^{\neq}$ transition state, and the arrangement of the overlap populations between Cr and the carbon of CO is $Cp^*(C_5H_7)$CrCO > Cp($C_5H_7$)CrCO > Cp(2,4-$C_7H_{11}$)CrCO.

• Journal of Pharmacopuncture
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• v.23 no.4
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• pp.237-246
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• 2020

Objectives: Capsaicin-containing (CP) pharmacopuncture was developed to treat neuropathic pain. This study was conducted to assess the toxicity of CP extract for pharmacopuncture, using a micronucleus test. Methods: First, a dose range finding study was conducted. Then an in vivo micronucleus test was performed to determine the induction of micronuclei in mouse bone marrow cells after intramuscular administration of CP twice with a 24-hour interval to 8-week-old ICR mice. A high dose of 0.2 mL/animal was selected, and this was sequentially diluted by applying a geometric ratio of 2 to produce two lower dose levels (0.1 and 0.05 mL/animal). In addition, negative and positive control groups were set up, and an HPLC analysis was conducted to confirm the capsaicin content of CP. Results: The incidence of micro-nucleated polychromatic erythrocytes in polychromatic erythrocytes in the CP-treated group was similar to that in the negative-control group, while that in the positive-control group was significantly greater. In addition, the ratio of polychromatic erythrocytes to total erythrocytes in the CP treatment group and the positive control group was not significantly different from the negative control group. In the HPLC analysis, capsaicin in the CP was identified through a comparison with the retention time of the capsaicin standard of 27 min. Conclusion: CP did not show any indication of any potential to induce micronuclei formation in bone marrow cells of ICR mice under the conditions of this study. Further toxicity studies are necessary to ensure the safety of the use of CP in clinical practice.

• Bulletin of the Korean Chemical Society
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• v.17 no.11
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• pp.1040-1044
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• 1996

The catalytic dehydrocoupling of bis(1-sila-3-butyl)benzene, 1 by Cp2ZrCl2/Red-Al and Cp2ZrCl2/n-BuLi combination catalysts yielded a mixture of oily and solid polymers. While the catalytic dehydrocoupling of 2-phenyl-l,3-disilapropane, 2 by Cp2ZrCl2/n-BuLi combination catalyst produced a mixture of oily and solid polymers, the catalytic redistribution/dehydrocoupling of 2 by Cp2ZrCl2/Red-Al combination catalyst gave oily polymer. The dehydrocoupling of 1 and 2, unless the prior silane redistribution occurs, seems to initially produce a low-molecular-weight polymer, which then undergoes an extensive cross-linking reaction of backbone Si-H bonds, leading to an insoluble polymer.

• Preventive Nutrition and Food Science
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• v.14 no.4
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• pp.362-366
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• 2009

To determine the effect of electron-beam irradiation on the contents of polymethoxylated flavones (PMFs) extracts from citrus pomaces (CP), CP was irradiated at 0, 1, 2, or 5 kGy. Methanol extract of the irradiated CP were prepared and the PMF (nobiletin, sinensetin, and tangeretin) content of the extract was determined. Nobiletin and sinensetin of CP extract significantly increased with irradiation dose-dependent. However, electron-beam irradiation decreased the amount of tangeretin in the CP extract. These data suggest that irradiation can liberate phenolic compounds such as nobiletin or sinensetin, but tangeretin might have different pathway of conversion by irradiation. Therefore, irradiation can be a tool to change the composition of PMFs in CP.

• Journal of Korea Technology Innovation Society
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• v.1 no.3
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• pp.313-325
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• 1998

Government-Supported Research Institutes(GSRI) have done complex product(CP) development with national needs. The products to be developed have very limited demand. The most important things at CP development are technology innovation through knowledge creation and acquisition. Then, this paper suggests the technology innovation system for CP development. In CP development like satellite, government must do strategic management at national level and technology management at program level. Two managements are tools to achieve the strategic goals. The key points in CP are integration and interface among subsystems and person. From these factors and innovation system, R&D planning and practice are based on sharing and creation of knowledge. CP development projects ought to overlap and parallel for sustainable acquisition and creation of knowledge.

• Korean Journal of Applied Biomechanics
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• v.16 no.3
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• pp.183-188
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• 2006

This research is to know differentiation of CP(center of pressure) pattern among four pitching sort(straight ball, raise ball, change up ball, drop ball). Subject are three national or junior athletes. We use the one camera, Novel Win pressure measurement system. Conclusions are as follows : 1. When we throw the straight ball, CP of left foot is effective to end movement at middle of foot in body balance on arm angular motion and enhanced speed. 2. When we throw the raise ball, to change CP from middle to post is more effective in order to raise the ball. 3.In drop ball pitching, in order to fall down the ball in front of hitter, CP of left foot move from post foot to interior part of forefoot 4. In change up ball pitching, if CP of left foot move into forefoot, it is a cause of high ball and hitter can recognize the change up ball because of late arm rotation motion.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.641-644
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• 2003