• Environmental Analysis Health and Toxicology
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• v.19 no.4
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• pp.367-373
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• 2004

Mancozeb, a polymeric complex of zinc and manganese salts of ethylene bisthiocarbamate (EBDC), is used widely in agriculture as fungicides, insecticides, and herbicides. Mancozeb can be occupationally and environmentally exposed to human and has been reported to induce estrogenic activity, therein it is considered as an endocrine disrupter. After female ICR mice were treated Mancozeb orally at the doses of 250, 1,000 and 1,500 mg/kg/day for consecutive 30 day, we investigated the effects of Mancozeb on the immunopathological parameters (body-, thymus-, spleen-, liver- and kidny-weight, splenic cellularity, hematological parameters) and mitogen (Con A, LPS)-induced splenocyte proliferation (SP). Liver- and kidney- weight were increased, but body- and thymus-weight, number of splenocytes and WBC were decreased, when compared with control group. When splenocytes isolated from the mice exposed to Mancozeb for 30 days were cultured in presence of mitogens, the SP against Con A was significantly and dose-dependently decreased and the SP against LPS was also slightly decreased. Our present results indicate that subacute exposure of Mancozeb to mice might show immunotoxic effect.

• Environmental Analysis Health and Toxicology
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• v.20 no.3 s.50
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• pp.243-248
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• 2005

Mancozeb (MCZ), a polymeric complex of zinr and manganese salts of ethylene bisthiocarbamate, is widely used in agriculture as fungicidel, insecticides, and herbicides. MCZ can be occupationally and environmentally exposed to human and has been reported to have detrimental effects on the reproductive system, but the toxicity of MCZ on immune responses has not been systematically investigated. We investigated the effects of MCZ exposure on the activities of murine splenocytes through evaluation of splenocytes cellularity and INF-$\gamma$ synthesis. Splenocytes were examned ex vivo from mice orally treated with various doEes of MCZ for 1 day (acute exposure, 2,100, 5,000, 10,000 mg/kg) or ior 5 consecutive days per week for 4 weeks (subacute exposure,250, 1,000, 1,500 mg/kg/day) fellowed by culture for 2 days in the presence of Con A or PHA plus IL-2. Splenocytes Iron naive mice were cultured with various concentration of MCZ (50, 500, 1,000 ng/ml) in the presence of Con A or PHA plus IL-2 for 2 days in vitro. IFN-$\gamma$ production was decreased with the in vitro exposure to all concentration of MCZ. The spleen cellularity and IFN -$\gamma$ production by splenocytes from MCZ -acutely and - subacutely exposured mice were decreased in comparision with that oi control group.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2980-2984
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• 2010

A new poly (vinyl chloride) (PVC) membrane electrode that is highly selective to $Mn^{+2}$ ions was prepared using N,N'-bis(2'-pyridinecarboxamide)-1,2-ethane ($bpenH_2$) as a suitable neutral carrier. This concentration range ($1.0{\times}10^{-5}$ to $1.0{\times}10^{-1}\;M$) with Nernstian slope of $29.3{\pm}0.5\;mV$ per decade. The detection limit and the response time of electrode were $8.0{\times}10^{-6}\;M$ and (${\leq}15\;s$) respectively. The membrane can be used for more than two months without observing any divergence. The electrodes exhibited excellent selectivity for $Mn^{+2}$ ion over other mono-, di- and trivalent cations. Selectivity coefficients were determined by the matched potential method (MPM). The electrode can be used in the pH range from 4.0 - 9.0. The isothermal coefficient of this electrode amounted to 0.00023 V/$^{\circ}C$. The stability constant (log $K_s$) of the $Mn^{+2}$ - $bpenH_2$ complex was determined at $25^{\circ}C$ by potentiometric titration in mixed aqueous solution. The proposed electrode was applied to the determination of $Mn^{+2}$ ions in real samples.

• Mycobiology
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• v.43 no.3
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• pp.297-302
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• 2015

Two white rot fungi, Ceriporia sp. ZLY-2010 (CER) and Stereum hirsutum (STH) were used as biocatalysts for the biotransformation of (-)-${\alpha}$-pinene. After 96 hr, CER converted the bicyclic monoterpene hydrocarbon (-)-${\alpha}$-pinene into ${\alpha}$-terpineol (yield, 0.05 g/L), a monocyclic monoterpene alcohol, in addition to, other minor products. Using STH, verbenone was identified as the major biotransformed product, and minor products were myrtenol, camphor, and isopinocarveol. We did not observe any inhibitory effects of substrate or transformed products on mycelial growth of the fungi. The activities of fungal manganese-dependent peroxidase and laccase were monitored for 15 days to determine the enzymatic pathways related to the biotransformation of (-)-${\alpha}$-pinene. We concluded that a complex of enzymes, including intra- and extracellular enzymes, were involved in terpenoid biotransformation by white rot fungi.

• Research in Plant Disease
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• v.21 no.2
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• pp.94-98
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• 2015

Tomato black leaf molds were collected from the six metropolitan cities, which were occurred mainly from the end of August until November. There was no significant difference on the fungal growth between potato dextrose agar and tomato-oatmeal agar media. The mycelial growth of the fungus was robust at a relatively high temperature, from 28 to $30^{\circ}C$. The suppression rates of hyphal growth ranged from 17-98% on the media supplemented with four different chemicals such as difenoconazole, fluquinconazole and prochloraz manganese complex, metconazole, and flutianil and there is no different suppression rates of the fungicides on the tested Pseudocercospora fuligena isolates.

• Journal of Forest and Environmental Science
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• v.37 no.2
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• pp.154-162
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• 2021

Blueberry, which produces phenolic compounds, is one of the most popular fruits in Korea. During a survey on blueberry diseases, 16 Colletotrichum isolates were obtained from blueberry leaves in Chuncheon and Gosung, Kangwon province, Korea. Using morphological and molecular analyses, the isolates were identified as Colletotrichum aenigma, C. fioriniae, C. fructicola, C. gloeosporioides, and C. nymphaeae. C. gloeosporioides was the most frequently isolated (11 isolates), and only one or two isolates of the other species were found. After inoculation with all isolates, those leaves and fruits with wounds easily developed anthracnose; whereas, fruits without wounds became infected but leaves without wounds were infected by only two of C. gloeosporioides. Typically, around seven fungicidal agents are used to control anthracnose on blueberries in Korea. Fluzinam and prochloraz manganese complex strongly (over than 80%) inhibited the growth of all Colletotrichum species, while dithianon and mancozeb only weakly (about 80% or less) inhibited their growth.

• Transactions of Materials Processing
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• v.32 no.5
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• pp.268-275
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• 2023

ISO 21029 cryogenic vessel is used to transport cryogenic fluids. High-manganese steel (High-Mn steel) is widely regarded as suitable for use at cryogenic temperatures. The conventional way of manufacturing an ellipsoidal vessel head involves incremental stretching, followed by a spinning process. In this study, an alternative method for forming an ellipsoidal vessel head was proposed. Finite element analysis (FEA) was used to theoretically examine the strain evolution during a multi-stage forming process, which involved progressive stretching, deep drawing, and spinning of High-Mn steel. The distribution of effective strain and strain components were analyzed at different regions of the formed part. The FEA results revealed that only normal strains were evident in the dished region of the vessel head due to the stretching process. However, the flange region experienced complex strain evolution during the subsequent deep drawing and spinning process.

• Journal of the Mineralogical Society of Korea
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• v.23 no.4
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• pp.281-295
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• 2010

This paper deals with magnetic susceptibility, mineralogy, soil properties (pH, EC, CEC, loss on ignition), iron and manganese oxides, the content and partitioning of heavy metals (As, Cd, Cr, Cu, Ni, Pb, Zn), and their mutual relationship in the soil samples of an unpolluted, abandoned mine area, and industrial complex area. The various minerals derived from weathered bedrock were identified by X-ray diffraction in the unpolluted soil samples, except for the magnetic minerals. XRD analysis also revealed the existence of hematite and magnetite related to mine tailings and waste rocks in the abandoned mine area samples. The industrial complex area samples had carbonate minerals, such as calcite and dolomite, that might be due to anthropogenic deposition. The sum of the reducible, oxidizable, and residual fractions was over 80% for the abandoned mine area samples and over 50% for the industrial complex area samples using the sequential extraction method. The industrial complex area samples had a relatively high carbonate fraction that was associated with carbonate minerals. The content of aqua regia-extractable Fe, Mn, As, and Zn had a high positive correlation with the content of the dithionite-citrate-bicarbonate (DCB)-extractable method related to Fe/Mn oxide phases. The 54% and 58% of aqua regia-extractable Fe and As content, respectively, acted together with the concentrations of the DCB-extractable phases. Magnetic susceptibility values of total samples ranged from 0.005 to $2.131{\times}10^{-6}m^3kg^{-1}$. The samples including iron oxide minerals, such as hematite and magnetite, had a high magnetic susceptibility. The magnetic susceptibility showed a significant correlation with the heavy metals, Cd (r=0.544, p<0.05), Cr (r=0.714, p<0.01), Ni (r=0.645, p<0.05), Pb (r=0.703, p<0.01), and Zn (r=0.496, p<0.01), as well as Fe (r=0.608, p<0.01) and Mn (r=0.615, p<0.01). The aqua regia-extractable Fe and Mn content had a significant positive correlation with Cd, Cr, Cu, Ni, and Zn. However, the DCB-extractable Fe and Mn content had a significant positive correlation with As and Ni, indicating that the heavy metals were associated with Fe and Mn oxide minerals.

• Korean Journal of Pharmacognosy
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• v.34 no.4 s.135
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• pp.327-334
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• 2003

We evaluated the anti-arthritic effect of a new diet-supplement product containing red ginseng, glucosamine, shark cartilage, ascorbic acid and manganese chloride for the relieving arthritic symptoms. Anti-inflammatory activities of the aqueous extract of red ginseng (250 and 500 mg/kg), glucosamine (240 mg/kg) and shark cartilage (240 mg/kg) were tested individually on vascular permeability and carrageenan-induced paw edema. Glucosamine and shark cartilage showed the inhibition of vascular permeability by 29.6 and 32.9%, respectively. Red ginseng (500 mg/kg) and shark cartilage showed the inhibition of carrageenan-induced paw edema at 0.5, 1, 2 and 3 hr. The supplement (red ginseng mixture: RGM) composed of red ginseng (43.5%), glucosamine (25.0%), shark cartilage (25.0%), ascorbic acid (5.0%) and manganese chloride (1.5%) was prepared and its inhibitory activities including vascular permeability and carrageenan-induced paw edema were comparable to anti-inflammatory drugs such as diclofenac and ibuprofen. It was also tested on adjuvant-induced arthritis in rats as one of chronic arthritic tests and Randall-Selitto assay as an analgesic test. RGM showed the inhibition against the swelling of rat paws induced by Mycobacterium tuberculosis at a dose of 1,500 mg/kg. Determination of cytokines of the sera sampled from arthritis-induced animals indicated that RGM increased the levels of $interferon-{\gamma}$ and interleukin-6, representing the immunostimulatory effect by red ginseng. RGM treatment moderately reduced the production of NO in RAW 264.7 cells in a dose-dependent manner. Taken together, these results support that RGM can be applicable for the improvement of arthritic as a new diet-supplement.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.91-91
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• 2013

Imagine a world where we could biomanufacture hybrid nanomaterials having atomic-scale resolution over functionality and architecture. Toward this vision, a fundamental challenge in materials science is how to design and synthesize protein-like material that can be fully self-assembled and exhibit information-specific process. In an ongoing effort to extend the fundamental understanding of protein structure to non-natural systems, we have designed a class of short peptides to fold like proteins and assemble into defined nanostructures. In this talk, I will talk about new strategies to drive the self-assembled structures designing sequence of peptide. I will also discuss about the specific interaction between proteins and inorganics that can be used for the development of new hybrid solar energy devices. Splitting water into hydrogen and oxygen is one of the promising pathways for solar to energy convertsion and storage system. The oxygen evolution reaction (OER) has been regarded as a major bottleneck in the overall water splitting process due to the slow transfer rate of four electrons and the high activation energy barrier for O-O bond formation. In nature, there is a water oxidation complex (WOC) in photosystem II (PSII) comprised of the earthabundant elements Mn and Ca. The WOC in photosystem II, in the form of a cubical CaMn4O5 cluster, efficiently catalyzes water oxidation under neutral conditions with extremely low overpotential (~160 mV) and a high TOF number. The cluster is stabilized by a surrounding redox-active peptide ligand, and undergo successive changes in oxidation state by PCET (proton-coupled electron transfer) reaction with the peptide ligand. It is fundamental challenge to achieve a level of structural complexity and functionality that rivals that seen in the cubane Mn4CaO5 cluster and surrounding peptide in nature. In this presentation, I will present a new strategy to mimic the natural photosystem. The approach is based on the atomically defined assembly based on the short redox-active peptide sequences. Additionally, I will show a newly identified manganese based compound that is very close to manganese clusters in photosystem II.