• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.406-411
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• 2001

In a bacterial denitrification test with Pseudomonas sp. and anaerobic consortium, more nitrates and less substrate were consumed but less metabolic nitrite was produced under an anaerobic $H_2$ condition rather than under $N_2$ condition. In a bioelectrochemical denitrification test with the same organisms, the electrochemically reduced neutral red was confirmed to be a substitute electron donor and a reducing power like $H_2$. The biocatalytic activity of membrane-free bacterial extract, membrane fraction, and intact cell for bioelectrochemical denitrification was measured using cyclic voltammetry. When neutral red was used as an electron mediator, the electron transfer from electrode to electron acceptor (nitrate) via neutral red was not observed in the cyclic voltammogram with the membrane-free bacterial extract, but it was confirmed to gradually increase in proportion to the concentration of nitrate in that of the membrane fraction and the intact cell of Pseudomonas sp.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.438-441
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• 2005

A mediator-less microbial fuel cell (MFC) was used to determine the performance effects of a membrane­electrode assembly (MEA). The MFC with an MEA generated a higher current with an increased coulomb yield when compared to an MFC with a separate cathode. Less oxygen was diffused through an MEA than through a Nafion membrane. The MFC performance was improved with a buffer, although a high-strength buffer reduced the performance.

• Environmental Engineering Research
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• v.19 no.4
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• pp.363-367
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• 2014

One chambered sediment microbial fuel cell (SMFC) was equipped with Fe, brass (Cu/Zn), Fe/Zn, Cu, Cu/carbon cloth and graphite felt anode. Graphite felt was used as common cathode. The SMFC was membrane-less and mediator-less as well. Order of anodic performance on the basis of power density was Fe/Zn ($6.90Wm^{-2}$) > Fe ($6.03Wm^{-2}$) > Cu/carbon cloth ($2.13Wm^{-2}$) > Cu ($1.13Wm^{-2}$) > brass ($Cu/Zn=0.24Wm^{-2}$) > graphite felt ($0.10Wm^{-2}$). Fe/Zn composite anode have twisted 6.73% more power than Fe alone, Cu/carbon cloth boosted power production by 65%, and brass (Cu/Zn) produced 65% less power than Cu alone. Graphite felt have shown the lowest electricity generation because of its poor galvanic potential. The estuarine sediment served as supplier of oxidants or electron producing microbial flora, which evoked electrons via a complicated direct microbial electron transfer mechanism or making biofilm, respectively. Oxidation reduction was kept to be stationary over time except at the very initial period (mostly for sediment positioning) at anodes. Based on these findings, cost effective and efficient anodic material can be suggested for better SMFC configurations and stimulate towards practical value and application.

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.84-93
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• 1993

It has been reported that ginseng is effective in the central nervous system, immune system, and the strong inflammatory responses. However, there has been no research report yet about the effect of ginseng on allergic hypersensitivity reactivity. To confirm the ginseng effects on the release of mediators(histamine. leukotrienes etc.) which cause the hypersensitivity reactivity and inflammatory response, we used actively sensitized guinea pig airway tissues by utilizing the superfusion technique. In this procedure. the contractile response and mediators released after antigen stimulation of sensitized tissues, and IgG and IgE antibody products were measured in sera of immunized animals. Then the results of the controll group were compared to those of ginseng pretreatment groups. In the total saponin(TS) and panaxatriol(PT) pretreatment, histamine release decreased by $20\%$ in the tracheal tissues after active sensitization by ovalbumin(OVA, 10mg/kg), but in the lung parenchyma, histamine release decreased by $40\%.$ Panaxadiol(PD) significantly decreased histamine release by $40\%$ in the both tissues after active sensitization. TS, PT and PD of ginseng poorly blocked leukotrienes (LTs) and prostagrandin $D_2(PGD_2)$ release(less than $10\%$). Ginseng TS and PT had no effect on the serum IgG antibody production by ovalbumin, whereas PD significantly increased serum IgG antibody contents(approximately by 2 times). However, $IgG_1$ antibody products in the serum of guinea pig actively sensitized with ovalbumin after PD pretreatment were decreased, compared to that with ovalbumin alone. IgE antibody production by passive cutaneous anaphylaxis(PCA) titer in the TS pretreatment increased 3 times more than in the absence of TS(PCA titer by PT was not detected). These studies show that some ginseng saponins can in part act to inhibit mediator release in antigen - induced airway smooth muscle by inducing the IgG antibody production which has been changed in the specificity.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1481-1484
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• 2006

In this study, glucose and glutamate (copiotrophic conditions) were used to enrich electrochemically active bacteria (EAB) in a microbial fuel cell (MFC). The enriched population consisted primarily of ${\gamma}$-Proteobacteria (36.5%), followed by Firmicutes (27%) and O-Proteobacteria (15%). Accordingly, we compared our own enrichments done under many different conditions with those reported from the literature, all of which support the notion that electrochemically active bacteria are taxonomically very diverse. Enrichments with different types and levels of energy sources (fuels) have clearly yielded many different groups of bacteria.

• Journal of the Korea Safety Management & Science
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• v.25 no.2
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• pp.59-69
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• 2023

Previous works on safety behavior have paid less attention to the influence of several leadership styles on safety behavior. Among the various leadership styles, I focus on the effect of coaching leadership on safety behavior. To be specific, this paper investigates the impact of coaching leadership on safety behavior and its underlying mechanisms (mediator) as well as contextual factor (moderator). This research examines the sequential mediating effect of perceived organizational support and organizational identification in the association between coaching leadership and safety behavior. Also, work overload will negatively moderate the coaching leadership-perceived organizational support link. My results showed coaching leadership increases employee safety behavior through the sequential mediation of perceived organizational support and organizational identification. In addition, work overload functions as a negative moderator which diminishes the positive effect of coaching leadership on perceived organizational support.

• Korea Trade Review
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• v.43 no.5
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• pp.139-158
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• 2018

As trade volume increases and the business environment becomes more complex and competitive, international trade disputes are also increasing and becoming more complex. Parties need to become more aware of alternatives to costly and time consuming arbitration and litigation. The ADR (Alternative Dispute Resolution) can encompass all dispute resolution processed and can act as a substitute for traditional litigation. Mediation, a type of ADR, offers an amicable dispute settlement mechanism between concerned parties through a natural mediator. There are several strong points of mediation compared with litigation or arbitration. First of all, mediation can take place without having to complete time-consuming and expensive discovery processes associated with litigation. In addition, since mediation is considered a private process, the dispute can remain out of the public eye. It can be embarrassing and disrupt business when customer or suppliers learn that a company is involved in litigation. Lastly, mediation is less adversarial than litigation or arbitration, so the parties often can salvage their relationships. Often the parties to mediation find themselves continuing to conduct business. In spite of such benefits of mediation, it is less used in Korea and therefore, this article aims to promote the mediation system in international trade disputes. However, this paper has limitation, for example, why ADR is not used well in Korea and need to suggest how ADR can work best in international trade disputes.

• Korean Journal of Culture and Social Issue
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• v.26 no.3
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• pp.167-194
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• 2020

In this study, we tested the hypothesis that a woman who claims sexual assault would be evaluated more negatively, and the suspected man would be judged more leniently, when the woman is agentic. In addition, we expected that this phenomenon would occur because the agentic accuser does not conform to the 'sexual crime victim' stereotype or feminine norms, and considered these as mediator variables. We also postulated that male (vs. female) participants would have a less positive regard of the agentic accuser and tested participant gender's moderating effects. Contrary to our hypothesis, participants criticized the agentic (vs. non-agentic) woman who claims sexual assault less and perceived her more positively and truthfully, and more likely to judged the suspected man to be guilty and recommended longer sentences. However, we observed the expected moderating effects of participant gender, so that male (vs. female) participants evaluated the agentic accuser more negatively. Mediation analyses yielded results on perceived truthfulness that were consistent with our hypothesis: Participants thought of agentic accuser as less feminine, which predicted less perceived truthfulness. Also, the less the agentic accuser was perceived to be feminine, male participants blamed her more while female participants had more positive impressions of her.

• Journal of Korean Academy of Nursing
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• v.33 no.6
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• pp.713-721
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• 2003

Purpose: This study was to determine the mediator or moderator role of social support in the relationship between stress and depression among family caregivers of older adults with dementia. Method: Sixty nine family caregivers were randomly selected from health care centers in P city and a face-to-face interview was conducted using questionnaires from January to May of 2002. Data were analyzed with descriptive statistics, Pearson correlation, and hierarchical multiple regression using SPSS program. Result: Family caregivers of older adults with higher dependency in ADLs and higher problematic behaviors, provided care to the older adults for a longer period of time, and perceived less social support reported higher depression. Social support showed mediating effects between stress and depression, while did not show moderating effects. Elderly dependency on ADLs and caregiving duration decreased perceived social support and decreased social support increased depression. Conclusion: To increase family and social support to the caregivers of more functionally impaired elderly, family education to increase emotional support and physical assistance to the caregivers and broader and flexible application of social support such as increasing accessibility to the elderly daycare service with lower price may prove beneficial.

• Journal of Labour Economics
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• v.26 no.1
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• pp.53-73
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• 2003

This paper investigates the success factors of labor mediation using the Survey on the Problems and Improvements of Mediation Service by the Labor Relation Commission which was conducted by the Ministry of Labor in 2000. When the parties of labor and management which took mediation service belong to the manufacturing industry and the Minju-nochong, they are found to have less chance to change their negotiation attitude favorably toward agreement in mediation process and to adopt an agreement proposal made by the mediator. Those who took mediation service more frequently in the past tend to have lower chance to make use of mediation service successfully. Those who saw the mediators of their dispute to be qualified with fairness and expertise tend to have higher chance. As the time of mediation meeting lengthens, it is more likely for them to reach an agreement with assistance by the mediators.