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Effects of Burnout on Job Stress and Ego-Resilience of Fire Officials (소방공무원의 직무스트레스와 자아탄력성에서 소진의 영향)

  • Lee, Hae-Young;Kim, Yeob-Rae
    • Fire Science and Engineering
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    • v.31 no.2
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    • pp.106-112
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    • 2017
  • This study examined the burnout intermediates between Fire officials' job stress and Ego-resilience. The objective of this study is to suggest a policy that improves Fire officials' Ego-resilience. This survey was given to 365 fire officials in northern Gyeonggi-do region and the data was analyzed by correlation analysis and regression analysis using SPPS 22.0. The hypothesis is the Fire officials' burnout would be related to Ego-resilience and the effect on Fire officials' job stress regarding Ego-resilience is associated with burnout. The results of the study are that unstable work and inadequate reward affect the measure of burnout, which manifests as sarcasm and job efficacy and reduces the Fire officials' Ego-resilience that results in a positive pointing of the future, emotion control and interest. The meaning of policy is as follows: First, Fire officials need to be given confidence in their work stability. Second, they have to receive social or financial rewards. Third, they require a continuous supporting policy that solves their tension, physical and mental fatigue. Finally, developing diverse educational programs will be needed to promote their Ego-resilience.

Effect of Red ginseng extract on immune function of Israeli carp, Cyprinus carpio. (홍삼추출물이 이스라엘잉어의 면역반응에 미치는 영향)

  • Choi, Min-Soon;Park, Sung-Woo;Park, Kwan-Ha
    • Journal of fish pathology
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    • v.18 no.3
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    • pp.277-285
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    • 2005
  • Israeli carps were intraperitoneally injected with an aqueous extract of red ginseng (RG) at five different concentrations (0, 1, 10, 25 and 50 mg/kg of body weight). The fish were sacrificed after 3 days and measured the neutrophil activity and plasma components. The activity of lysozyme, Ht, TIC and NBT reduction were significantly enhanced in the concentrations of more than 10 mg/kg. Further attempts were made to measure the effects of RG on leucocyte function at five different concentrations (1-100 ${\mu}g/m{\ell}$), in vitro. The proliferation of lymphocytes co-incubated with phytohaemagglutin (PHA) and concanavalin A (Con A) was significantly increased at 10 ${\mu}g/m{\ell}$ concentration, but suppressed at the highest concentration (100 ${\mu}g/m{\ell}$). RG alone or with lipopolysaccharide (LPS) had no effect on proliferation at any concentrations tested. Migration and reactive oxygen intermediates (ROI) production of leucocytes were enhanced in all concentration higher than 10 ${\mu}g/m{\ell}$. These results suggest that the RG activates the leucocyte function and may be able to be used as a stimulant of fish innate defences.

The role of nitric oxide as an effector of macrophage-mediated cytotoxicity against Trichomonas vaginalis (질편모충에 대한 대식세포의 세포독성에 있어서 NO의 역할)

  • Park, Geon-Chae;Ryu, Jae-Suk;Min, Deuk-Yeong
    • Parasites, Hosts and Diseases
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    • v.35 no.3
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    • pp.189-196
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    • 1997
  • The purpose of this study is to determine whether nitric oxide is involved in the extracellular killing of Trichomoncs uasinalis by mouse (BALB/c) peritoneal macrophages and RAW264.7 cells activated with LPS or rIFN-γ and also to observe the effects of various chemicals which affect the production of reactive nitrogen intermediates (RNl) in the cytotoxicity against T. vnginnlis. The cytotoxicity was measured by counting the release of (3H)-thymidine from labelled protozoa and NOa was assayed by Griess reaction. Nemonomethyl-L-arginine (L-NMHA), Nenitro-L-arginine methyl ester (NAME) and arginase inhibited cytotoxicity to T. vaginnlis and nitrite production by activated mouse perioneal macrophagrs and RAW 264.7 cells. The addition of excess L-arginine competitively restored trichomonacidal activity of macrophages. Exogenous addition of FeSO4 inhibited cytotoxicity to T. vaginaLis and nitric products of macrophages. From above results, it is assumed that nitric oxide plays an important role in the host defense mechanism of macrophages against T ucfinalis.

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Effect of Soil Fumigation and Maize Cultivation on Reduction of Replant Failure in Ginseng (토양 훈증 및 녹비작물 재배가 인삼의 연작장해 경감에 미치는 영향)

  • Lee, Sung Woo;Lee, Seung Ho;Seo, Moon Won;Jang, In Bok;Jang, In Bae;Yu, Jin;Moon, Ji Won;Suh, Soo Jung
    • Korean Journal of Medicinal Crop Science
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    • v.26 no.3
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    • pp.248-253
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    • 2018
  • Background: Dazomet are widely used as soil fumigant to solve soilborne problems, and the degradation intermediates are toxic to nematodes, fungi, bacteria, insects and weeds. Methods and Results: The effects of cultivation of green manure crop, maize before and after soil fumigation on the control of ginseng root rot disease were compared using soil where 6-years-old ginseng was harvested. Fumigant (dazomet) were used for soil fumigation in May and September, respectively. Maize was grown for soil management before and after soil fumigation. After May fumigation, the sowing date of maize was delayed by 15 days and thus its dry weight was decreased significantly. Maize cultivation after May fumigation increased pH but decreased EC, $NO_3$, $P_2O_5$, and K significantly. Maize cultivation after May fumigation decreased fungi population and the ratio of fungi and bacteria. Growth of 2-years-old ginseng was improved and the incidence of ginseng root rot was significantly decreased by maize cultivation after May fumigation. After harvesting 2-years-old ginseng, the population of Cylindrocarpon destructans was not different between treatment of May and September, but Fusarium solani showed a significant increase in September fumigation after maize cultivation. Conclusions: Maize cultivation after soil fumigation was effective in inhibiting ginseng root rot by the amendment of mineral composition and microorganism in fumigated soil.

Protective Effects of Water Extracts Composed of Adenophora triphylla var. japonica Hara on the Acetaminophen-induced Hepatotoxicity (아세트아미노펜에 의해 유도된 간독성 모델에서 잔대를 주원료로 하는 추출물의 간 보호 효과)

  • Gum, Sang-Il;Lee, Dong-Ung;Cho, Min-Kyung
    • Korean Journal of Food Science and Technology
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    • v.39 no.6
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    • pp.688-693
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    • 2007
  • The hepatoprotective effects of water extracts composed of Adenophora triphylla var japonica Hara (ATJH) on acetaminophen (APAP)-induced hepatotoxicity were investigated in vivo and in vivo. The effects of ATJH on liver toxicity induced by APAP were assessed by blood biochemical and histopathological analyses. APAP treatment (350 mg/kg) caused severe liver injury in mice as indicated by their significantly elevated plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. Pretreatment with ATJH for 3 or 7 days attenuated the increases in ALT and AST when challenged with APAP. The reductions in viability caused by high dose of APAP (450 mg/kg) in vivo were reversed by pretreatment with ATJH. These protective effects of ATJH against APAP-induced toxicity were consistent with the results from the histopathological examinations. We next examined the effects of ATJH on the gene expression of glutathione S-transferases (GSTs) that detoxify the metabolic intermediates of APAP in H4IIE cells. The hepatic GST protein levels [$\alpha$ class (GSTA2, GSTA3/5)] were significantly elevated in a dose-dependent manner by ATJH treatment. In summary, ATJH is effective at protecting against APAP-induced hepatotoxicity by GST induction, implying that ATJH should be considered a potential chemopreventive agent.

Biodegradation of Recalcitrant Chlorinated Aromatic Compounds via Microbial Dechlorination (미생물의 탈염소화 작용에 의한 난분해성 염화방향족 오염물질의 분해)

  • 채종찬;김치경
    • Korean Journal of Environmental Biology
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    • v.17 no.2
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    • pp.129-138
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    • 1999
  • Chlorinated aromatic compounds are one of the largest groups of environmental pollutants as a result of world-wide distribution by using them as herbicides, insecticides, fungicides, solvents, hydraulic and heat transfer fluids, plasticizers, and intermediates for chemical synthesis. Because of their toxicity, persistence, and bioaccumulation, the compounds contaminated ubiquitously in the biosphere has attracted public concerns in terms of serious influences to wild lives and a human being, such as carcinogenicity, mutagenicity, and disturbance in endocrine systems. The biological recalcitrance of the compounds is caused by the number, type, and position of the chlorine substituents as well as by their aromatic structures. In general, the carbon-halogen bonds increase the recalcitrance by increasing electronegativity of the substituent, so that the dechlorination of the compounds is focused as an important mechanism for biodegradation of chlorinated aromatics, along with the cleavage of aromatic rings. The removal of the chlorine substituents has been known as a key step for degradation of chlorinated aromatic compounds under aerobic condition. This can occur as an initial step via oxygenolytic, reductive, and hydrolytic mechanisms. The studies on the biochemistry and genetics about microbial dechlorination give us the potential informations for microbial degradation of xenobiotics contaminated in natural microcosms. Such investigations might provide biotechnological approaches to solve the environmental contamination, such as designing effective bioremediation systems using genetically engineered microorganisms.

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Expression of Cu/Zn SOD according to H2O2 in Hepatoma cell line (Hepatoma 세포주에서 H2O2 처리에 의한 Cu/Zn SOD의 발현)

  • Kim, Young-Min;Seo, Won-Sook
    • Journal of Life Science
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    • v.17 no.2 s.82
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    • pp.230-234
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    • 2007
  • Oxygen is required for many important aerobic cellular reactions, it may undergo electrontransfer reactions, which generate highly reactive membrane-toxic intermediates (reactive oxygen species, ROS), such as hydrogen peroxide, singlet oxygen, superoxide radical, hydroxyl radical, hydroperoxyl radical, hydroxy ion. Various mechanisms are available to protect cells against damage caused by oxidative free radicals, including scavenging enzyme systems such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). This antioxidant defense system is a very complex and finely tuned system consisting of enzymes capable of detoxifying oxygen radicals as well as low molecular weight antioxidants. In addition, repair and turnover processes help to minimize subcellular damage resulting from free radical attack. $H_2O_2$,one of the major ROS, is produced at a high rate as a product of normal aerobic metabolism. The primary cellular enzymatic defense systems against $H_2O_2$ are the glutathione redox cycle and catalase. From Northern blot analysis of total RNAs from cultured cell with $H_2O_2$ treatment, various results were obtained. Expression of Cu/Zn SOD decreased when cell passage increased, but the level of the Cu/Zn SOD was scarcely expressed in 35 passage.

Preparation of La0.5Nd0.5Ni5 Alloy by an Electrochemical Reduction in Molten LiCl (LiCl 용융염에서 전해환원법을 통한 La0.5Nd0.5Ni5 합금 제조)

  • Lim, Jong Gil;Jeong, Sang Mun
    • Korean Chemical Engineering Research
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    • v.53 no.2
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    • pp.145-149
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    • 2015
  • The electrochemical behavior of $Nd_2O_3-La_2O_3-NiO$ mixed oxide including rare earth resources has been studied to synthesize $La_{0.5}Nd_{0.5}Ni_5$ alloy in a LiCl molten salt. The $Nd_2O_3-La_2O_3-NiO$ mixed oxide was converted to $NiNd_2O_4$ (spinel) and $LaNiO_3$ (perovskite) structures at a sintering temperature of $1100^{\circ}C$. The spinel and perovskite structures led a speed-up in the electrolytic reduction of the mixed oxide. Various reaction intermediates such as Ni, $NiLa_2O_4$ were observed during the electrochemical reduction by XRD analysis. A possible reaction route to $La_{0.5}Nd_{0.5}Ni_5$ in the LiCl molten salt was proposed based on the analysis result.

Characterization of immobilized laccase and its catalytic activities (고정된 laccase의 특성 및 촉매효과)

  • Hyung Kyung Hee;Shin Woonsup
    • Journal of the Korean Electrochemical Society
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    • v.2 no.1
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    • pp.31-37
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    • 1999
  • Copper-containig enzyme, laccase (Rhus vernicifera) was immobilized onto gold electrode using self-assembly technique and its surface properties and catalytic activities were examined. Laccase is an oxidoreductase capable to oxidize diphenols or diamines by 4-electron reduction of molecular oxygen without superoxide or peroxide intermediates. The electrode surface were modified by $\beta-mercaptopropionate$ to have a net negative charge in neutral solution and positively charged laccase (pI=9) was immobilized by electrostatic interaction. The successful immobilization was confirmed by cyclic voltammograms which showed typical surface-confined shapes and behaviors. The amount of charge to reduce the surface was similar to the charge calculated assuming the surface being covered by monolayer. The activity of the immobilized enzyme was tested by the capbility of oxidizing a substrate, ABTS (2,2-azine-bis-(3-ethylbenzthioline-6-sulfonic acid) and it was maintained for $2\~3$ days at $4^{\circ}C$. The immobilzed laccase showed about $10\~15\%$ activity compared to that in solution. The laccase-modified electrode showed the activity of elefoocatalytic reduction of oxygen in the presence of mediator, $Fe(CN)_6^{3-}$ The addtion of azide which is an inhibitor of laccase compeletly eliminated the catalytic current.

A Study on Deketalization of Rigid ${\beta}$-Aminoketones (형태가 고정된 ${\beta}$-아미노케톤의 탈케탈화 (반응) 의 연구)

  • Jack C. Kim;Yong Tae Lee;Ung Chan Yoon;In-Seop Cho;Sung Hwan Moon;Sun Hong Han
    • Journal of the Korean Chemical Society
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    • v.32 no.6
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    • pp.557-566
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    • 1988
  • The causes of failure in the deketalization of rigid ${\beta}$-aminoketals were separately investigated by examining the deketalization of 3 ketals, 2-ethylenedioxy-l-acenaphthenylamine (2), N-(2-ethylenedioxy-l-acenaphthenyl)acetamide(13) and trimethyl-2-ethylenedioxy-1-acenaphthenylammonium iodide(14), and by examining the deketalization of non-rigid ${\beta}$-aminoketal, 2-amino-l-ethylenedioxyacetophenone(19) and non-rigid aliphatic acetals, dimethylaminoformaldehyde dimethylacetal (20) and 2-aminoactaldehyde dimethyl acetal(21). While compounds 2 and 14 were not able to be hydrolyzed in the various acidic conditions 13 was easily deketalized. The result indicated the importance of electrostatic repulsion in the possible dicationic intermediates as a factor of failure in the deketalization. The observations of easy deketalization of compounds 19, 20 and 21 indicated that the structural characters of rigid $\beta-aminoketals$ are also important factors in the hydrolysis of ${\beta}$-aminoketals.

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