• Title/Summary/Keyword: MC

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Effect of Insecticide Carbofuran and Phenobarbital Sodium and 3-Methylcholanthrene on Activity of Enzyme in Israeli Carp(Cyprinus israeli carpio L.) (살충제 Carbofuran과 Phenobarbital Sodium 및 3-Methylcholanthrene이 이스라엘 잉어의 효소활성에 미치는 영향)

  • Rim, Yo-Sup;Jeong, Jae-Hun;Han, Seong-Soo
    • Applied Biological Chemistry
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    • v.39 no.1
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    • pp.77-83
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    • 1996
  • Effects of insecticide carbofuran and Phenobarbital sodium(PB) or 3-methylcholanthrene(3-MC) on activities of several enzymes in israeli carps were investigated. Survival number of Israeli carp was the same as that of control when PB and 3-MC only was treated, individually and that was low compared to control when carbofuran only was treated. But survival rate of Israeli carp was high compared to individual treatment of carbofuran when combination treatment of carbofuran and PB or 3-MC was carried out. These results indicate that PB and 3-MC can intervene to detoxify carbofuran exposed to israeli carp. In in vivo test for the effect of this chemicals on activity of enzyme in israeli carp, activities of acetylcholinesterase(AChE) and glutathione S-transferase(GST) were inhibited in carbofuran treatment, but did not in combination treatment of carbofuran and P3 or 3-MC. Activities of UDP-glucuronosyltransfe-rase (UDPGT) and cytochrome P-450-dependent monooxygenase increased in individual or combined treatments of carbofuran and PB or 3-MC. These results suggest that a simultaneous application of carbofuran and PB or 3-MC is critical for the enhancement of activity of AChE, GST, UDPGT and monooxygenase and the protection of Israeli carp from carbofuran toxicity.

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Changes in the Stability Properties of Methylcellulose Emulsions as Affected by Competitive Adsorption Between Methylcellulose and Tween 20 (메칠셀룰로오스/Tween 20 경쟁 흡착이 메칠셀룰로오스 유화액의 안정도 특성에 미치는 영향)

  • Hong, Soon-Taek
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.10
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    • pp.1278-1286
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    • 2008
  • The effect of Tween 20 addition on changes in the stability of methylcellulose (MC) emulsions (1 wt% MC, 10 wt% n-tetradecane, 20 mM bis-tris buffer, pH 7) was investigated by creaming stability and orthokinetic stability measurements. In the case of MC emulsions containing varying amounts of oil (1$\sim$30 wt%) and no Tween 20 added, creaming stability, judged by mean migration velocity of fat globules ($V_m$), was found to depend on droplet size: the larger the droplet size, the worse the stability [$V_m$: 0.326 $\mu$m $min^{-1}$ ($d_{32}$: 0.32 $\mu$m) ${\rightarrow}V_m$: 0.551 $\mu$m $min^{-1}$ ($d_{32}$: 0.53 $\mu$m)]. With Tween 20, creaming stability was found to be worse than the one without Tween 20, except for MC emulsion containing 0.2 wt% Tween 20. In addition, cream stability was the lowest with the lowest concentration of Tween 20 and a tendency to recover with increasing Tween 20 concentration [$V_m$: 0.598 $\mu$m $min^{-1}$ (0.01 wt%)${\rightarrow}V_m$: 0.389 $\mu$m $min^{-1}$ (0.2 wt%)] was found. From viscosity measurement for aqueous bulk phase of MC emulsions, such a change in the creaming stability was found to coincide well with the results of viscosity measurement. Therefore, it was reasonable to say that creaming stability of MC emulsions containing Tween 20 depended on MC concentration in aqueous bulk phase, which was in turn varied by competitive adsorption between MC and Tween 20 at the oil droplet surface. In case of orthokinetic stability, judged by destabilization time ($t_d$), it was found that the addition of Tween 20 resulted in lowered stability with more pronounce tendency at higher concentrations [$t_d$: 160 min (0.03 wt%)${\rightarrow}t_d$: 100 min (0.2 wt%)]. Moreover, combined with previous results, the orthokinetic stability of MC emulsions containing Tween 20 was found to be exponentially proportional to MC load. In conclusion, competitive adsorption between MC and Tween 20 may affect the stability properties of MC emulsion to varying extents, depending on the concentration of Tween 20.

Research on the PAPR Reduction Method using Selection of Extra Code Set in PB/MC-CDMA System (PB/MC-CDMA 시스템에서 여분의 코드집합을 이용한 PAPR 감쇄기법에 관한 연구)

  • Lee, Kyu-Jin;Lee, Dong-Joon;Lee, Kye-San;Kim, Jin-Young
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.8 no.1
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    • pp.110-118
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    • 2009
  • The PB/MC-CDMA(Partial Block Multi Carrier Code Division Multilple Access) system can improve the performance by reducing the ICI(Inter-Code Interference) between users. Also, this system can achieve the frequency diversity gain by avoiding ISI(Inter Symbol Interference). Therefore, the performance of PB/MC-CDMA system is better than that of conventional MC-CDMA(Multi Carrier Code Division Multiple Access) system. However, similarly to other multi-carrier systems, it still has a PAPR(Peak to Average Power Ratio) issue. In this paper, we propose a peak power reduction technique involving optimized spreading code selection without side information for the PB/MC-CDMA. The PB/MC-CDMA system in each block of units reuses the code so the extra code will be remained. This extra code is divided into several groups to calculate the PAPR and solving the PAPR problem by transferring the selected code which has minimum peak power.

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Development of Melanotropin Antagonists: Investigating Potent and Specific Ligands for New Receptors

  • Lim, Sejin
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.11a
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    • pp.153-159
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    • 1996
  • ${\alpha}$-Melanotropin (Ac-Ser-Tyr- Ser-Met-Glu$\^$5/-His-Phe-Arg-Trp-Gly$\^$10/-Lys-Pro-Val-NH$_2$) is one of the first peptide hormones to be isolated and have its structure determined. It was early recognized to have essentially the same N-terminal tridecapeptide sequence as adrenocorticotropic hormone (ACTH) except that the N-terminal was acetylated in the case of ${\alpha}$-MSH but not in the case of ACTH, indicating that their biosyntheses were different (Figure 1). Subsequently it was discovered that ${\alpha}$-MSH and ACTH were derived from the same gene, currently referred to as proopiomelanocortin (POMC). Its original bioactivity was pigmentation, but it also was recognized that it may have activity in the central nervous system, though the precise nature of these central activities have been controversial. The recent cloning and expression of five melanocortin receptors, with the MC3 and MC4 receptors found primarily in the brain and the MC5 receptor (MC5-R) found throughout the body, has provided new impetus to understand the structure-activity relationships of ${\alpha}$-MSH at these receptors. The effects of ${\alpha}$-MSH on pigmentation are mediated by the MC1-R expressed specifically on the surface of melanocytes. Similarly the MC2-R is involved in the regulation of adrenal steroidogenesis by ACTH. However, given the complexity of expression of the MC3, MC4, and MC5 receptors, it has not been possible to identify any simple correlations between these receptors and the reported biological activities of the melanocortin peptides. Consequently, potent and receptor specific agonists and especially antagonists would be extremely valuable tools for the determination of the physiological roles of the MC3, MC4, and MC5 receptors. Though the extensive structure-activity relationships have provided much information on agonist activity related to pigmentary effects, only recently has it been possible to begin to systematically develop potent and selective antagonists.

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Comparison of chemical compounds of medicinal plant materials with compounds of domestic pharmacopoeias (식물 약재 구성성분과 국내 약전 성분과의 비교 연구)

  • Kim, Sang-Kyun;Lee, Seungho;Kim, Anna
    • The Korea Journal of Herbology
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    • v.31 no.5
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    • pp.55-62
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    • 2016
  • Objective : TM-MC was constructed to provide information on the chemical compounds of medicinal plant materials which were listed in Korean, Chinese, and Japanese pharmacopoeias. The aim of this study was to compare of the chemical compounds of TM-MC with those of domestic pharmacopoeias.Methods : First of all, TM-MC was updated on medicinal materials and chemical compounds which were extracted from articles up to the PubMed identifier of 26 millions. After searching for medicinal plant materials with information on their major compounds in Korean pharmacopoeias, we identified that the information on medicinal materials and chemical compounds were also existed in TM-MC. Then, we figured out how much the compounds have been studied by counting the number of articles for those compounds in TM-MC.Results : Information on 9 medicinal materials and about 1,700 compounds was newly added to TM-MC after manually curating 645 articles. Korean pharmacopoeias contained a total of 91compounds from 53 medicinal plant materials, while TM-MC provided information on the 89 compounds from the 53 medicinal materials in Korean pharmacopoeias. The compounds stated in Korean pharmacopoeias has been much studied by comparison with other compounds of each medicinal material in TM-MC.Conclusion : Most of chemical compounds stated in Korean pharmacopoeias were also listed in TM-MC, excluding two compounds. Thus, we concluded that information in TM-MC is mostly consistent with that of Korean pharmacopoeias. In the future, we will periodically update TM-MC with articles added to the MEDLINE.

Studies on the MC1R Gene Frequencies in Landrace, Large White, Duroc and Jeju Native Black Pigs (랜드레이스, 대요크셔, 듀록 및 제주 흑돈의 Melanocortin 1 Receptor(MC1R) 유전자의 유전자형 분석)

  • Cho, I.C.;Lee, J.G.;Jung, J.G.;Yang, B.S.;Kang, S.Y.;Kim, B.W.
    • Journal of Animal Science and Technology
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    • v.44 no.2
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    • pp.207-212
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    • 2002
  • This study was conducted to investigate the genotypes and frequencies of Melanocortin 1 Receptor(MC1R) genes in pigs which plays a central role in regulation of eumelanin (black/brown) and phaeomelanin(red/yellow) pigment synthesis within the mammalian melanocytes. Four different breeds of pigs(20 Landrace, 20 Yorkshire, 20 Duroc, and 93 Jeju native black pigs) were used and PCR-RFLP analysis of MC1R gene was also carried out. Two regions of MC1R genes (428bp and 405bp) were amplified using two specific primers (MERL1-EPIG2, EPIG1-EPIG3), respectively and MC1R allele were determined using 2 restriction enzymes (BspHⅠ, AccⅡ). The results of this experiment indicated that MC1R allelic type in Landrace, Large Yorkshire and Duroc were MC1R *2 (Ep), MC1R *2 (Ep), MC1R *4 (e), respectively. However, various allelic types of MC1R genes were detected in Jeju native black pigs. MC1R allelic type of Jeju black pigs was MC1R*2 type as in Meishan and Large black breeds or MC1R*3 type as in Hampshire and Berkshire breeds and the gene frequencies of ED1 and ED2 were 0.554 and 0.446 in average.

Studies on the Cellulase Producing Microorganisms(Part I) -Isolation of the Cellulase Producing Molds and their Cultural Conditions- (Cellulase 생성균(生成菌)에 관(關)한 연구(硏究) (제1보(第1報)) -유용균(有用菌)의 분리(分離) 및 그 배양조건(培養條件)에 대(對)하여-)

  • Kim, Chan-Jo;Choi, Woo-Young
    • Applied Biological Chemistry
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    • v.11
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    • pp.83-88
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    • 1969
  • 94 Cellulase producing strains were isoated from soils, composts, rotten woods and straws, and gastric contents and feces of herbivorous animals in various places. Among them, the strain MC-9, MC-10, MC-53 and MC-61 were found to be highly active in the degradation of carboxy methyl cellulose. Their cultural conditions adequate for the cellulase formation and effects of inorganic salts and various organic substances added to the wheat bran media were investigated. The results obtained are as follows; 1. Optimum conditions for the cellulase formation were MC-9: pH 5.5, temp. $35^{\circ}C$, incubation time 5 days, MC-10: pH 5.5-6.0, temp. $30^{\circ}C$, incubation time 5 days, MC-53: pH 3.5, temp. $30^{\circ}C$, incubation time 5 days, MC-61: pH 3.5-4.0, temp. 30-$35^{\circ}C$, incubation time 5 days. 2. Their cellulase activity in their optimum conditions were MC-9: CMC-LP(liquefying power). 87.7%, CMC-SP(saccharifying power) 3.20 glucose mg./gm. of the cultures/min., MC-10: CMC-LP 82.9%, CMC-SP 2.48 glucose mg./gm. of the cultures/min., MC-53: CMC-LP 72.4%, CMC-SP 1.76 glucose mg./gm. of the cultures/min., MC-61: CMC-LP 87.1%, CMC-SP 2.08 glucose mg./gm. of the cultures/min. 3. Additions of inorganic salts to the wheat bran media were not significant for the cellulase formation, but additions of soybean film and orange-peel pomace promoted the CMC-liquefying power 3 to 5 percent in wheat bran cultures of the strains.

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Performance Evaluation of MC-DS-CDMA Systems over Time Variant Channels (시변 채널 하에서의 MC-DS-CDMA 시스템의 성능 분석)

  • Choi, Seung-Kuk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.3
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    • pp.581-586
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    • 2010
  • MC-DS-CDMA is technique where a single data symbol is transmitted at multiple subcarriers which are orthogonal to each other. With this technique, frequency diversity can be achieved. Time variant channels lead to interchannel interference which increases the bit error rate for MC-DS-CDMA systems. The performance of PSAM MC-DS-CDMA system over time variant channels is analyzed. The BER performance of this system over multipath fading environment is evaluated, considering the channel estimation error, carrier frequency offset.

Efficient Resource Allocation Scheme for Improving the Throughput in the PB/MC-CDMA System (PB/MC-CDMA 시스템에서 처리량 향상을 위한 효율적인 자원 할당 기법)

  • Lee, Kyujin;Seo, HyoDuck;Han, DooHee
    • Journal of Convergence Society for SMB
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    • v.4 no.1
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    • pp.1-6
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    • 2014
  • PB/MC-CDMA is an efficient system which divides the whole frequency band into several blocks, unlike a conventional MC-CDMA system. We propose an efficient resource allocation scheme in Multi-Block PB/MC-CDMA (Partial Block Multi-Carrier Code Division Multiple Access). This system aims to improve frequency efficiency and maximize the total throughput while satisfying predefined threshold over various channel conditions. Through computer simulations, we confirm that the performance of the proposed system is more effective in terms of throughput.

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