• Journal of Distribution Research
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• v.12 no.1
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• pp.1-31
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• 2007

While trust and commitment are core mediating variables for the purpose of maintaining the long-term relationship, in the context of the characteristics of company and the relationship performance of its members, there have been limited studies which explore as to how each of the dimensions has affects differently. The basic purpose of this study is to examine the relationship between an automobile manufacturer and its agencies. The main purpose of this study is to examine how each different dimension of trust and commitment on the automobile manufacturer has different mediating effects between the characteristics of company(organization characteristics, relationship characteristics) and relationship performance perceived by its agents. Another purpose is to investigate the mechanism by which the relationship performance of the agencies is improved. An empirical study surveying 115 sales office managers at a leading automobile manufacturer in Korea was conducted. An analysis of the collected data indicates that while the characteristics of company have a positive influence on the agencies' relational performance through the mediating role of both trust of benevolence and commitment, agencies' trust of their headquarter's benevolence has a different influence on the dimensions of commitment. Finally, the authors discussed some theoretical contributions and managerial implications. And then, they presented limitations of this study and the future research directions.

• Food Science of Animal Resources
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• v.32 no.6
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• pp.842-848
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• 2012

This study was performed to investigate the physicochemical properties and tenderness of Hanwoo loin and round cuts, as affected by various raising periods and marbling scores. Five loin and round cuts with various marbling scores (5-9) from Hanwoo at various raising periods (27, 33, 30 mon) were collected. pH, Hunter color values (L, a, b), chemical composition, cooking loss, vacuum purge, and Warner-Bratzler shear values were evaluated according to two-way analysis of variance. No differences in pH values of Hanwoo loin were observed by raising period and marbling scores (p>0.05), but those of Hanwoo round at 27 mon was the lowest. Increased Hunter color values were observed with the increased marbling score and those at 27 and 30 mon were lower than 33 mon. Redness (a) and yellowness (b) of Hanwoo round cuts with the raising period of 27 mon were higher than those at 30 and 33 mon. The raising period of 27 mon showed higher water holding capacity than those of 30 and 33 mon, regardless of Hanwoo cut. Increased shear values (kgf) of Hanwoo round cuts were observed with increasing raising period (p<0.05). Increased marbling score decreased shear values in loin cuts, but no differences were observed in the round cuts. Based on these results, the parameters measured varied with meat cut, and raising period affected round pH, color, chemical composition, vacuum purge, and shear values. Marbling score affected color, chemical composition, water binding capacity, and shear values in loin cuts (p<0.05), but didn't affect any parameters in round cuts (p>0.05).

• Food Science of Animal Resources
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• v.33 no.3
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• pp.411-416
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• 2013

This study aimed to examine the mechanisms underlying the effects of Garcinia cambogia extract on the adipogenic differentiation of 3T3-L1 cells and long-chain saturated fatty acid-induced lipotoxicity of HepG2 cells. 3T3-L1 preadipocytes, mouse embryonic fibroblast-adipose like cell line, were treated with MDI solution (0.5 mM IBMX, 1 ${\mu}M$ dexamethasone, 10 ${\mu}g/mL$ insulin) to generate a cellular model of adipocyte differentiation. Using this cellular model, the anti-obesity effect of Garcinia cambogia extract was evaluated. MDI-induced lipid accumulation and expression of adipogenesis-related genes were detected by Oil red O staining, Nile Red staining, and Western blot analysis. Effects Garcinia cambogia extract on palmitate-induced lipotoxicity was also analyzed by MTT assay, LDH release, and DAPI staining in HepG2 cells. Garcinia cambogia extract significantly suppressed the adipogenic differentiation of preadipocytes and intracellular lipid accumulation in the differentiating adipocytes. Garcinia cambogia extract also markedly inhibited the expression of peroxisome proliferator- activated receptor ${\gamma}2$ ($PPAR{\gamma}2$), CCAT/enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$), and adipocyte protein aP2 (aP2). In addition, Garcinia cambogia extract significantly attenuated palmitate-induced lipotoxicity in HepG2 cells. Palmitateinduced cellular damage and reactive aldehydes were also significantly reduced in the presence of Garcinia cambogia extract. These findings suggest that the Garcinia cambogia extract inhibits the adipogenic differentiation of 3T3-L1 preadipocytes, probably by regulating the expression of multiple genes associated with adipogenesis such as $PPAR{\gamma}2$, $C/EBP{\alpha}$, aP2, and thereby modulating fatty acid-induced lipotoxicity to reduce cellular injury in hepatocytes.

• Korean Journal of Microbiology
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• v.48 no.3
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• pp.180-186
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• 2012

Pseudomonas aeruginosa, a Gram-negative bacterium, is an ubiquitous and opportunistic human pathogen, which expresses many virulence factors through quorum sensing (QS) regulation. QscR, one of the QS signal receptors of P. aeruginosa, has unique features that make it possible to distinguish QscR from other QS receptors. In the present study, we focused on amino acid residues responsible for such a broad signal specificity of QscR. Thus we constructed mutant QscRs: $QscR_{T72I}$, $QscR_{R132M}$, and $QscR_{T140I}$ by substituting $72^{nd}$ threonine, $132^{nd}$ arginine, and $140^{th}$ threonine residues with isoleucine, methionine, and isoleucine, respectively by site-directed mutagenesis. When we examined the activity of these mutant QscRs, $QscR_{R132M}$ failed to respond to N-3-oxododecanoyl homoserine lactone (3OC12-HSL), but $QscR_{T72I}$ and $QscR_{T140I}$ remained the ability to respond to 3OC12-HSL despite much reduction of the sensitivity. When we treated a variety of acyl-HSLs with different structure, $QscR_{T72I}$ and $QscR_{T140I}$ showed better responsiveness to N-decanoyl HSL (C10-HSL) or N-dodecanoyl HSL (C12-HSL) that has no oxo-moiety at $3^{rd}$ carbon of acyl group than to 3OC12-HSL, and $QscR_{R132M}$ showed no responsiveness to any acyl-HSLs tested here. In addition, $QscR_{T72I}$ and $QscR_{T140I}$ were inhibited by 5f, a QscR inhibitor as similarly as wild type QscR was. These results suggest that while the $130^{th}$ arginine is crucial in both activity and acyl-HSL binding of QscR, the $72^{nd}$ and $140^{th}$ threonines are important in the activity, but they are little responsible for the discrimination of acyl-HSLs or competitive inhibitor.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.278-285
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• 2016

The bifunctional PheA protein, having chorismate mutase and prephenate dehydratase (CMPD) activities, is one of the key regulatory enzymes in the aromatic amino acid biosynthesis in Escherichia coli, and is negatively regulated by an end-product, phenyalanine. Therefore, PheA protein has been thought as useful for protein engineering to utilize mass production of essential amino acid phenylalanine. To obtain feedback resistant PheA protein against phenylalanine, we mutated by using random mutagenesis, extensively screened, and obtained $pheA^{FBR}$ gene encoding a feedback resistant PheA protein. The mutant PheA protein contains substitution of Leu to Phe at the position of 118, displaying that higher affinity (about $290{\mu}M$) for prephenate in comparison with that (about $850{\mu}M$) of wild type PheA protein. Kinetic analysis showed that the saturation curve of $PheA^{FBR}$ against phenyalanine is hyperbolic rather than that of $PheA^{WT}$, which is sigmoidal, indicating that the L118F mutant enzyme has no cooperative effects in prephenate binding in the presence of phenylalanine. In vitro enzymatic assay showed that the mutant protein exhibited increased activity by above 3.5 folds compared to the wild type enzyme. Moreover, L118F mutant protein appeared insensitive to feedback inhibition with keeping 40% of enzymatic activity even in the presence of 10 mM phenylalanine at which the activity of wild type $PheA^{WT}$ was not observed. The substitution of Leu to Phe in CMPD may induce significant conformational change for this enzyme to acquire feedback resistance to end-product of the pathway by modulating kinetic properties.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.390-395
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• 2004

In order to characterize ion channels present in tomato roots, microsomes were incorporated into an artificial lipid bilayer arranged for electrophysiological analysis. Of the five different ion channels that could be found, a channel of 450 pS conductance was found most frequently. This channel displayed subconductance states of 450, 257 and 105 pS. All subconductance states showed linear current-voltage relationships. At positive holding potentials, high frequency of transient channel openings was observed; however, at negative potentials, the open times were long and open probability high. Po was 0.83 at -40 mV. When an additional 50 mM $K^+\;or\;Na^+$ was added to the cis side of bilayer, the reversal potentials shifted in the negative direction to near -10 mV. Thus, the 450 pS cation channel selects poorly between $K^+\;and\;Na^+$. In the presence of $100\;{\mu}M$ metal ions, the channel activity was severely inhibited by $La^{3+},\;Ba^{2+},\;and\;Zn^{2+}$, and Po was decreased to 0.2 or even less. However, $Al^{3+}\;and\;Cd^{2+}$ decreased the activity by only 20%. Interestingly, each metal ion showed different kinetics of channel inhibition. While $500\;{\mu}M\;La^{3+}$ inhibited the activities of all subconductance state, 1 mM $Zn^{2+}$ inhibited all except the 105 pS state. $Cd^{2+}$ changed the gating of the channel from a long-opening state to brief transient openings even at negative holding potentials. These data represent that the metal ions may have different binding sites on the channel protein and could be useful modulators and probes to investigate structural characteristics as well as the functional roles of the 450 pS channel on the root physiology.

• Journal of Acupuncture Research
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• v.22 no.3
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• pp.37-51
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• 2005

Mast cell is a cell that functions mainly in our body with a respect to inflammation and allergic response. Bee venom has been progressed in a study as a model related to mechanism in alleviation of pain until now, but it is being progressed in a study relevant to immunocyte in anti-inflammation or anti-allergic response. The present study is aimed to present the basis related to a future study of gene, by researching the influence of melittin and MCD Peptide, which are major ingredients in Bee venom, upon the expression of gene in the mast cell strain. In this study, it dealt with melittin and MCD Peptide respectively, in the effective concentration after passing though the experiment of cytotoxicity by using human mast cell strain. Also, with the respect in the aspect of expression in gene that changes at this time, information was obtained through the technique of analyzing microarray. Through experimental statistics, when regarding a case that global M is significant in more than 1 or -1, in melittin, all 7 genes were accelerated, and 8 inhibited. In MCDP, 7 genes were accelerated and 17 genes inhibited. The function in the body to which these genes are related, was associated with the protein binding within a cell, the activation in the function of lymphocyte, the acceptor related to macrophage antigen. In cell nucleus, substance related to GABA A receptor, protein associated with cAMP reactive element, substance related to complement system No.8 and to B-cell, protein substance related to polycystic kidney disease, substance related to inflammation, and the protein substance of influencing coagulation of blood. Through these results of analysis, it could obtain more useful materials in clarifying the mechanism of action in melittin and MCD peptide, which are in charge of mainly medical action in the abdomen. Also, it is thought that an in-depth study on the influence of main ingredients in Bee venom, the wholly honey bee venom aqua upon anti-allergic response or anti-inflammation are further required.

• The Korean Journal of Malacology
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• v.22 no.2
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• pp.157-165
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• 2006

The present study was conducted to confirm that a bivalve Ruditapes philippinarum can be used as a biomarker for the monitoring of the heavy metal pollution in the silt of the marine environment. The clams were collected from the silt of Cheonsu-bay, Buheung-ri, and Tan-island of the West Sea, Korea. To observe the normal structures of the target organs (hepatopancreas and gill), they were dissected out for the immunohistochemical study and the electron microscopy with TEM, SEM, and SEM-EDS. The immunohistochemical study showed that the interdiverticular connective tissues of the hepatopancreas, and the outer epithelium of the gill lamellae was strongly reacted to anti-metallothionein (MT), indicating the presence of MT, a metal-binding protein, involved in metal detoxifying process. According to the examinations under the TEM, the epithelial cells of the hepatopancreas of the clams collected from polluted area (Tan-island) showed certain changes such as swollen rER, swollen nuclear envelope and inclusion bodies in the nulcei. In the SEM-EDS analysis, tissue of the hepatopancreas showed relatively higher concentration of S, Zn, and Cd. These elements are supposed to be concerning with the MT-reaction in the hepatopancreas. Considering that the coastal bivalve R. philippinarum showed immediate subcellular responses to heavy metal pollution in the overall experiments conducted, this species might act as one of efficient biomarkers for the heavy metal contamination in the marine environment.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.243-247
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• 2006

The biological activity of functional food source with thyme extracts were examined. Total phenol contents in the 60% ethanol extracts $(26.8{\pm}0.35\;mg/g)$ with thyme leaf was higher than water extracts $(25.7{\pm}0.20\;mg/g)$. This HPLC analysis is significant in that physiological activity is related with phenolic compound content such as rosemarinic acid, quercetin and chlorogenic acid. Electron donating ability was shown as 90.1% in the water extracts and 77.7% in the 60% ethanol extracts. Antioxidant protection factor of 60% ethanol extracts was higher than water extracts. Helicobacter pylori of the water extracts from thyme leaves did not have antimicrobial activity, but the 60% ethanol extracts revealed the high antimicrobial activity as 9 mm of clear zone in $50\;{\mu}g/ml$ of phenol content, 10 mm in $100\;{\mu}g/ml$, 13 mm in $150\;{\mu}g/ml$ and 16 mm in $200\;{\mu}g/ml$, respectively. Angiotensin converting enzyme inhibition activity showed no inhibition activity in 60% ethanol extracts but 39.9% inhibition activity in water extracts. Xanthine oxidase inhibition activity showed high inhibition activity at 73.5% in water extracts and 100% in 60% ethanol extracts. The result suggests the development of phenol compound in thyme as anti Helicobacter pylori, antioxidant and anti-gout agents.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.2
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• pp.75-85
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• 2010

The purpose of this study is to attempt new analysis on Soswaewon Garden(瀟灑園) where is Korea's traditional garden, focusing on which the tendency of its change is a relational-formation tool similar to the Eastern Mode of Thought, with paying attention to conversion as the new view of world. Accordingly, the aim is to reanalyze by connecting with Soswaewon Garden based on the theory of complexity, which tries to look at the whole through relationship rather than characteristics in individual components. Given summarizing findings, those are as follows. First, it was found that complexity shown in space and open system of physical dimension was characterized by 'event(situation)', 'non-determination' and 'homogeneous relationships between part and whole', and a variety of techniques introduced the nature positively. In particular, it was found that there were many cases of topographic usage, since the Soswaewon Garden selected its construction site proactively and was a product from architectural works in compliance with a given flow of natural topography. This has a nature of open text in the situation of emergent behaviors. Second, it was found that complexity shown in experiences and open system on the invisible dimension was characterized primarily by 'event(situation)' and 'relationships of interactive response between actors and environment', and various techniques appeared as a space for interactive combination of nature and daily experiences. This is typical of bilateral harmony based on interactions between subject and object, and between mankind and nature, and becomes also a space to accommodate temporary emergent behaviors in our life. Third, the compositional elements are reconstituted as space of organic property with dismantling steady relations. Especially, 'Soswaewon Garden's 48 poems(瀟灑園四十八詠)' will be the origin of the emotionally spatial experience to the current performers. Ultimately, the performer in the space of Soswaewon Garden simultaneously becomes a creator of space, and will generate new space with intertextuality with environment. Therefore, Soswaewon Garden becomes a place of binding me and the other together while maintaining mutual relationship based on organic thinking between a human being and nature and between the whole and a part.