• Title/Summary/Keyword: manganese

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Induction of Oxidative Stress by Mananese Chloride in Cultured $H_9C_2$ Cells (랫드 심근세포유래 $H_9C_2$ 세포주에서의 망간화합물의 산화적스트레스 유도작용)

  • Park, Eun-Jung;Park, Kwang-Sik
    • YAKHAK HOEJI
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    • v.52 no.3
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    • pp.212-218
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    • 2008
  • Manganese is a naturally occurring element which is widespread in the environment. Also, manganese is an essential trace element and plays a key role in important biological reactions catalyzed by enzymes. However, exposure to high levels of manganese can cause toxicity in neurone and inhalation system, also damage in various tissues. We investigated the toxicity induced by manganese compound ($MnCl_2$) in cultured rat cardiomyocytes. Treatment of manganese to cultured cardiomyocyte led to cell death, reactive oxygen species (ROS) increase, and cytosolic caspase-3 activation. The ROS increase was related with the decreased level of glutathione. Expressions of ROS related genes such as heme oxygenase-1, thioredoxin reductase, and NADH quinone oxidase were significantly induced in manganese treated cells. These results suggest that manganese induce oxidative stress and apoptosis in cardiomyocytes, and may be the one of risk factors to cause heart dysfunction in vivo.

Analysis of Manganese Content in Frequently Consumed Foods by Koreans (한국인 상용 식품 중 망간 함량 분석)

  • Choi, Mi-Kyeong;Kim, Eun-Young
    • Journal of Nutrition and Health
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    • v.40 no.8
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    • pp.769-778
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    • 2007
  • Using ICP-AES, we analyzed manganese content in 366 foods consumed frequently by Koreans. For the analysis, it was included a total of 366 foods such as 51 kinds of grains, 7 kinds of potatoes and starches, 7 kinds of sugars and sweeteners, 12 kinds of legumes, 11 kinds of nuts and seeds, 68 kinds of vegetables, 7 kinds of mushrooms, 33 kinds of fruits, 13 kinds of meats, 4 kinds of eggs, 48 kinds of fishes and shellfishes, 7 kinds of seaweeds, 16 kinds of milks, 8 kinds of oils and fats, 27 kinds of beverages, 34 kinds of seasonings, 13 kinds of processed foods and others. Among the grains, starches and sugars, manganese content of rice was 0.745 mg/100g. As for legumes, the content of manganese in soybean milk was 0.033 mg/100g and in black beans was 4.075 mg/100g. In nuts and seeds, the content of manganese in gingko nuts was 0.268 mg/100g while that in pine nuts was 8.872 mg/100g. Among the vegetables, manganese contents were 0.061 mg/100g in cherry tomato and 14.017 mg/100g in ginger. In mushrooms, the highest manganese content was displayed in ear mushroom at 10.382 mg/100g. Dried jujube and shrimp were found to be the fruits and fishes with high manganese contents at 2.985 mg/100g and 3.512 mg/100g, respectively. Among dairy foods, oils and beverages, manganese content was the highest in instant coffee powder at 2.577 mg/100g. Seasonings and processed foods posted 0.010 mg/100g in Sagolgomtang, instant soup and 23.846 mg/100g in pepper. In a furture, more various food for manganese content needs to be analyzed and a reliable food database should be compiled from the findings of researches in order to estimate manganese consumption accurately.

A study on manganese health hazards among experienced welders (용접경력자의 망간에 의한 건강 장해에 관한 연구)

  • Kim, Gyu-Hoi;Lim, Hyun-Sul;Yu, Sun-Hee
    • Journal of Preventive Medicine and Public Health
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    • v.31 no.4 s.63
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    • pp.644-665
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    • 1998
  • This study was conducted to evaluate the health hazards and to develop early diagnostic methods of the manganism in experienced welders and to know the meaning of signal intensities on the brain Magnetic Resonance images. It was carried out from December 1996 to february 1997 with 277 male welders, the duration of welding was at least 5 years or more. The study was consisted of a questionnaire, physical examination and measurements of blood & urine manganese concentrations. Brain Magnetic Resonance imaging was done on 19 study subjects by random sampling. As the duration of welding increases, the positive rates of clinical symptoms, neurological examinations and blood manganese concentrations were also increased. However, physical examinations and urine manganese concentrations were not statistically significant with the duration of welding. Authors couldn't observe any Parkinsonism-like diseases. There were statistically significant correlations between duration of welding and blood manganese concentration(r=0.16, p<0.01). There were not statistically significant correlations between duration of welding and urine manganese concentrations (r=0.06). There were statistically significant correlations between blood & urine manganese concentration(r=0.34, p<0.01). By viewing brain Magnetic Resonance images, 13 welders(68.4 %) among 19 welders were found to have signal intensities. The positive rates of clinical symptoms, physical examinations, neurological examinations and blood & urine manganese concentrations were not statistically different between those with signal intensities and those without signal intensities. We would like to suggest that some non-specific clinical symptoms and neurological signs are correlated with the duration of welding but any Parkinsonism-like diseases had not been observed with these welders. Next we suggest that the high signal intensities on TlWI of brain Magnetic Resonance images are not the sign of manganese intoxication but the sign of manganese deposition.

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A Study on Operation of Sand Filters Coated with Manganese (망간사화된 모래여과지 운영에 관한 연구)

  • Jeong, Se-Chae;Ko, Su-Hyun;Kim, Jin-Keun;Yoo, Jeong-Hee
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.5
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    • pp.558-562
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    • 2006
  • Filtration experiments were conducted to determine the characteristics of manganese removal in filtration using 4 different filter media including sand and manganese sand(MS). Filtration velocity was 123 m/d and the flow rate was $3.9m^3/d$ per column. Duration of these experiments was about one year, and manganese dioxide accumulation, turbidity removal, manganese removal, and organic material removal were examined depending on filter media. When filter influent(residual chlorine 1.0 mg/L) with an average manganese concentration of 0.208 mg/L was fed through a filter column, the sand+MS and MS columns removed 98.9% and 99.2% of manganese respectively on an annual basis. When there is need to replace the sand filters with a MS filter to remove manganese, it was shown that the replacement of a partial sand filter with MS had adequate manganese removal.

Catalytic Oxidation of Toluene by Manganese Oxide: (II) Support and Precursor Effect (망간 산화물에 의한 톨루엔 촉매 산화 반응: (II) 담체 및 전구물질 영향)

  • Cheon Tae-Jin;Choi Sung-Woo;Lee Chang-Soep
    • Journal of Korean Society for Atmospheric Environment
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    • v.21 no.3
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    • pp.277-284
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    • 2005
  • Catalytic oxidation of toluene in low concentrations was investigated over various supports. As the manganese oxides loading was increased, the conversion of toluene increased at a lower temperature. The 18.2 $wt\%$ $Mn/\gamma-Al_2O_3$ appeared to be the most active catalyst. Among the supports, $\gamma-Al_2O_3$ was more active than $TiO_2$ and $SiO_2$. Manganese oxide catalysts prepared from manganese nitrate precursor were better for complete oxidation of toluene than those prepared from manganese sulfate and chloride precursor because sulfate from manganese sulfate and chloride from chloride manganese remained even after the calcination by XRD (X-Ray Diffraction) analyses.

Electrical Conductivity Change of Manganese oxide with Addition of Transition Metal (천이금속 첨가에 따른 이산화망간의 전기전도도 변화)

  • Kim, Bong-Seo;Lee, Dong-Yoon;Lee, Hee-Woong;Chung, Won-Sub
    • Proceedings of the KIEE Conference
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    • 2005.07c
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    • pp.2028-2030
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    • 2005
  • The electrical conductivity of manganese oxide and complex manganese oxide produced by anodic deposition method was measured. The additive transition metal is Cu, Co and Fe. The transition metals like as Cu, Co and Fe improved electrical conductivity of complex manganese oxide compared with manganese oxide. This is coincide with the results of molecular orbital calculation by DV-Xa.

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Study of a hybrid process combining ozonation and ceramic membrane for drinking water treatment (I) : manganese removal (정수처리를 위한 전오존-세라믹 막여과 조합공정에 관한 연구(I) : 망간 제거 중심)

  • Jin, Kwang Ho;Lim, Jae Lim;Lee, Kyung Hyuk;Wang, Chang Gun
    • Journal of Korean Society of Water and Wastewater
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    • v.22 no.6
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    • pp.633-640
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    • 2008
  • In this research, the $3.6m^3/day$ scale pilot plant consisting preozonation, coagulation, flocculation, and ceramic membrane processes was operated for long term period to evaluate the validity of ceramic membrane filtration process for treating lake water containing high concentration manganese. The higher concentration of dissolved manganese($Mn^{2+}$) was effectively oxidized to the bigger insoluble colloidal manganese ($MnO^2$) by 1~2 mg/L ozone. The colloidal manganese reacted with coagulant (poly aluminium chloride, PAC) and then formed the big floc. Ceramic membrane rejected effectively manganese floc during membrane filtration. Dissolved organic carbon(DOC) removal was dependent upon $Mn^{2+}$ concentration. While average $Mn^{2+}$ concentration was 0.43 and 0.85 mg/L in raw water, DOC removal rate in preozonation was 26.5 and 13.5%, respectively. The decrease rate of membrane permeability was faster without preozonation than with preozonation while membrane fouling decreased with NOM oxidation by ozone. In conclusion, raw water containing high concentration of manganese can be effectively treated in preozonation-coagulation-ceramic membrane filtration system.

Data Driven Approach to Forecast Water Turnover (데이터 탐색 기법 활용 전도현상 예측모형)

  • Kwon, Sehyug
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.41 no.3
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    • pp.90-96
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    • 2018
  • This paper proposed data driven techniques to forecast the time point of water management of the water reservoir without measuring manganese concentration with the empirical data as Juam Dam of years of 2015 and 2016. When the manganese concentration near the surface of water goes over the criteria of 0.3mg/l, the water management should be taken. But, it is economically inefficient to measure manganese concentration frequently and regularly. The water turnover by the difference of water temperature make manganese on the floor of water reservoir rise up to surface and increase the manganese concentration near the surface. Manganese concentration and water temperature from the surface to depth of 20m by 5m have been time plotted and exploratory analyzed to show that the water turnover could be used instead of measuring manganese concentration to know the time point of water management. Two models for forecasting the time point of water turnover were proposed and compared as follow: The regression model of CR20, the consistency ratio of water temperature, between the surface and the depth of 20m on the lagged variables of CR20 and the first lag variable of max temperature. And, the Box-Jenkins model of CR20 as ARIMA (2, 1, 2).

Manganese Dioxide-Based Chlorination of Alcohols Using Silicon Tetrachloride (이산화망간 존재하에서 사염화규소를 이용한 알코올의 염소화반응)

  • Ha, Dong Soo;Yoon, Myeong Jong
    • Journal of the Korean Chemical Society
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    • v.41 no.10
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    • pp.541-546
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    • 1997
  • Manganese dioxide may react with silicon tetrachloride to form manganese(Ⅳ) oxodichloride which reacts subsequently with another molecule of silicon tetrachloride leading to manganese tetrachloride eventually in chlorinated solvents. This in situ generated manganese(Ⅳ) oxodichloride or manganese tetrachloride were found to be very effective for the chlorination of a wide variety of alcohols to the corresponding chlorides. Primary, secondary and benzylic alcohols were converted into corresponding chlorides when treated with silicon tetrachloride in the presence of manganese dioxide at room temperature.

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Characterization of Total and Size-Fractionated Manganese Exposure by Work Area in a Shipbuilding Yard

  • Jeong, Jee Yeon;Park, Jong Su;Kim, Pan Gyi
    • Safety and Health at Work
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    • v.7 no.2
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    • pp.150-155
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    • 2016
  • Background: Shipbuilding involves intensive welding activities, and welders are exposed to a variety of metal fumes, including manganese, that may be associated with neurological impairments. This study aimed to characterize total and size-fractionated manganese exposure resulting from welding operations in shipbuilding work areas. Methods: In this study, we characterized manganese-containing particulates with an emphasis on total mass (n = 86, closed-face 37-mm cassette samplers) and particle size-selective mass concentrations (n = 86, 8-stage cascade impactor samplers), particle size distributions, and a comparison of exposure levels determined using personal cassette and impactor samplers. Results: Our results suggest that 67.4% of all samples were above the current American Conference of Governmental Industrial Hygienists manganese threshold limit value of $100{\mu}g/m^3$ as inhalable mass. Furthermore, most of the particles containing manganese in the welding process were of the size of respirable particulates, and 90.7% of all samples exceeded the American Conference of Governmental Industrial Hygienists threshold limit value of $20{\mu}g/m^3$ for respirable manganese. Conclusion: The concentrations measured with the two sampler types (cassette: total mass; impactor: inhalable mass) were significantly correlated (r = 0.964, p < 0.001), but the total concentration obtained using cassette samplers was lower than the inhalable concentration of impactor samplers.