• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.1
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• pp.72-81
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• 2012

Using artificial neural network (ANN) technique, auction prices for common mackerel were forecasted with the daily total sale and auction price data at the Busan Cooperative Fish Market before introducing Total Allowable Catch (TAC) system, when catch data had no limit in Korea. Virtual input data produced from actual data were used to improve the accuracy of prediction and the suitable neural network was induced for the prediction. We tested 35 networks to be retained 10, and found good performance network with regression ratio of 0.904 and determination coefficient of 0.695. There were significant variations between training and verification errors in this network. Ideally, it should require more training cases to avoid over-learning, which leads to improve performance and makes the results more reliable. And the precision of prediction was improved when environmental factors including physical and biological variables were added. This network for prediction of price and catch was considered to be applicable for other fishes.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.652-658
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• 1995

We attempted simultaneous expression of genes coding for endoglucanase and $\beta $-glucosidase from Pseudomonas sp. by using a synthetic two-cistron svstem in Escherichia coli and Saccharomyces cerevisiae. Two-cistron system, 5'--tac promoter-endoglucanase gene--$\beta $-glucosidase gene-- 3', 5'-tac promoter--$\beta $-glucosidase gene--endoglucanase gene--3' and 5'-tac promoter--endoglucanase gene--SD sequence--$\beta $-glucosidase gene--3, were constructed, and expressed in E. coli and S. cerevisiae. The E. coli and S. cerevisiae contained two-cistron system produced simultaneously endoglucanase and $\beta $-glucosidase. The recombinant genes contained the bacterial signal peptide sequence produced low level of endoglucanase and $\beta $-glucosidase in S. cerevisiae transformants: Approximately above 44% of two enzymes was localized in the intracellular fraction. The production of endoglucanase and $\beta $-glucosidase in veast was not repressed in the presence of glucose or cellobiose. The veast strain contained recombinant DNA with two genes hydrolyzed carboxvmethyl cellulose, and these endoglucanase and $\beta $-glucosidase degraded CMC synergistically to glucose, cellobiose and oligosaccharide. This result suggests the possibility of the direct bioconversion of cellulose to ethanol by the recombinant yeast.

• Journal of Fisheries and Marine Sciences Education
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• v.10 no.2
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• pp.162-183
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• 1998

The fisheries resources control system in the Fisheries Act of Korea is introducing technical management method and input control method that controls fishing effort. Fishing effort control system of Korea aiming at realizing the maximum sustainable yield does not regulating the limitation of fishing quota and the limitation of fisheries object target fish. Therefore fishing operators who have fishing permit can use fishery resources without any restriction of fishing quota. But there are no rules that can controlling capacity of productivity of fishing by developing of fishing technic and fishing gear. For those reasons, productivity of fishing is superior to reproductivity of fisheries resources. Therefore, the Fisheries Act of Korea rearranges a legal basis for an introduction of fisheries resources management system by TAC, but the contents to be possible for a legal guarantee is not included and it is exceedingly defective as abstract and institutional devices. And that the affairs to be required for an enforcement of the said regime was placed in an administrative mandatory legislation and the danger to be degenerated is high in accordance with the bureaucratic self-righteous and/or the coercion of group's interest concerned and accordingly its substitute legislation system is keenly required. TAC system that is going to be introduced in our country is expected to enforce the Olympic fishing method and the individual quota method in parallel. This method is not certainly proper, because it occurs to overcapitalize and to compete fishing amounts between fishery operators. So as to prevent overcapitalization and fishing competition between fishery operators, and the exhaustion of coastal fisheries resources, individual transferable quota system should be introduced in Korean sea. Accordingly this thesis has attempted to constitute a view to improving problems of the traditional fisheries resources control system and introducing TAC fisheries resources control system.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.334-337
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• 2008

A tightly regulated gene expression system composed of a single-copy target gene under the control of a lac promoter derivative and lacI gene in a multicopy plasmid is proposed, and its ability to control the flux of a metabolic pathway is demonstrated. A model system to control the flux of acetyl-CoA to acetyl phosphate was constructed by integrating pta, a gene encoding phosphotransacetylase, under a tac promoter into the chromosome of E. coli with a pta-negative background and transforming a multicopy plasmid containing the $lacI^Q$ gene into the strain. The production rate of acetate was shown to be tightly controlled when varying the concentration of the inducer (IPTG) in he model system.

• The Journal of Fisheries Business Administration
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• v.54 no.3
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• pp.17-28
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• 2023

In this study, a conjoint analysis was conducted to derive a combination of fishing quota management system by fish species preferred by fishermen. In the analysis, detailed levels were set according to each attribute of the system. For analysis, this study conducted a design question survey for conjoint analysis on 303 fishermen engaged in fishing activities in the offshore and coastal sea. The Conjoint analysis was conducted on all fishermen, offshore fishermen and coastal fishermen. In addition, an analysis was conducted on TAC system participants and non-TAC system participants, and the targets were classified for comparison according to the characteristics of fishermen. Fishermen's preference for the system confirmed for six attribute ("catching fish even if there is no fishing quota", "how to allocate fishing quota", "fishing quota management agency", "upper limit of fishing quota," "Possibility of Trading in the Fishing Quota", and "Application of Other Regulations.") and the detailed level of each attribute. As a result of the analysis of the importance of attributes, fishermen thought that "fishing quota management agency (24.1%)" was very important, and "catching fish even if there is no fishing quota (23.9%)" and "how to allocate fishing quotas (22.9%)" were also given some importance.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.31-32
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• 2008

• Magazine of the Korea Institute for Structural Maintenance and Inspection
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• v.16 no.3
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• pp.19-22
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• 2012

• Development and Reproduction
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• v.20 no.1
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• pp.51-61
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• 2016

Neurokinin B (NKB) and neurokinin B related peptide (NKBRP) belong to tachykinin peptide family. They act as a neurotransmitter and/or neuromodulator. Mutation of NKB and/or its cognate receptor, NK3R resulted in hypogonadotropic hypogonadism in mammals, implying a strong involvement of NKB/NK3R system in controlling mammalian reproduction. Teleosts possess NKBRP as well as NKB, but their roles in fish reproduction need to be clarified. In this study, NKB and NKBRP coding gene (tac3) was cloned from Nile tilapia and sequenced. Based on the sequence, Nile tilapia NKB and NKBRP peptide were synthesized and their biological potencies were tested in vitro pituitary culture. The synthetic NKBRP showed direct inhibitory effect on the expression of GTH subunits at the pituitary level. This inhibitory effect was confirmed in vivo by means of intraperitoneal (ip) injection of synthetic NKB and NKBRP to mature female tilapia (20 pmol/g body weight [BW]). Both NKB and NKBRP had no effect on the plasma level of sex steroids, E2 and 11-KT. However, NKBRP caused declines of expression level of GnRH I, Kiss2 and tac3 mRNAs in the brain while NKB seemed to have no distinct effect. These results indicate some inhibitory roles of NKBRP in reproduction of mature female Nile tilapia, although their exact functions are not clear at the moment.

• Journal of Pharmacopuncture
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• v.10 no.3
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• pp.53-62
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• 2007

Objective The objective of this study was to investigate the antioxidative effects of Puerariae Radix extract. Method Total antioxidant capacity (TAC), Total antioxidant response (TAR), Total phenolic content, Reactive oxygen species (ROS), 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activities, lipid peroxidation were examined. Result Total antioxidant status was examined by total antioxidant capacity(TAC) and total antioxidant response(TAR) against potent free radical reactions. TAC and TAR of Puerariae Radix extract at the concentration of 5 mg/ml were 2.02 and 1.50 mM Trolox equivalents, respectively. Total phenolic content of Puerariae Radix extract at the concentration of 5 mg/ml was 2.29 mM gallic acid equivalent. Concentration of Puerariae Radix extract at which DPPH radical scavenging activity was inhibited by 50% was 5.91 mg/ml as compared to 100% by pyrogallol solution as a reference. The inhibitory effect of the extract on lipid peroxidation was examined using rat liver mitochondria induced by FeSO4/ascorbic acid. Puerariae Radix extract at the concentration of 1 mg/ml slightly but significantly decreased TBARS concentration. The extract further prevented lipid peroxidation in a dose-dependent manner. The effect of Puerariae Radix extract on reactive oxygen species (ROS) generation was examined using cell-free system induced by hydrogen peroxide/FeSO4. Addition of 1 mg/ml of Puerariae Radix extract significantly reduced dichloroflurescein (DCF) fluorescence. The extract caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that the extract significantly prevented ROS generation in vitro. Thus antioxidant effects of Puerariae Radix extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation, followed by inhibition of lipid peroxidation. Conclusion As a result, Puerariae Radix seems to have antioxitative effect and antioxidant compount.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.288-296
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• 1995

To investigate high-level expression of Serratia marcescens metalloprotease (SMP) in Escherichia coli and S. marcescens, we constructed various recombinant plasmids: pSP2, containing SMP gene and lac promoter; pKSP2, containing SMP gene and tac promoter; pTSP2, containing SMP gene, trc99a promoter, and lacI$^{q}$. The recombinant E. coli (pKSP2) strain expressed SMP to a high-level, about 36% of total cellular proteins but accumulated inactive SMP precursors intracellularly, which indicated that E. coli does not have activation and secretion system for SMP. To overproduce active SMP, we transformed S. marcescens with the recombinant plasmids by a modified CaCl$_{2}$ method. The recombinant S. marcescens ATCC27117 (pSP2) containing lac promoter for SMP transcription produced 530 U/ml of active SMP on LB broth, which is about 5.1 times of the SMP yield, 105 U/ml of a control strain, S. marcescens ATCC27117 (pUC19). However, S. marcescens ATCC27117 (pKSP2) containing tac promoter for SMP transcription did not grow healthy and hardly produced SMP. To overcome a harmful effect of the strong tac promoter, we constructed a regulatory plasmid pTSP2 containing a strong trc99a promoter and its repressor gene lacI$^{q}$. When S. marcescens ATCC27117 (pTSP2) was induced with 1.0 mM IPTG after 9 hr cultivation, 2,200 U/ml of SMP was obtained in LB broth, which is about 21 times of that of a control strain.