• YAKHAK HOEJI
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• 제48권1호
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• pp.41-46
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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, We investigated the effects of acute exposure of Mancozeb on the immune function in mice. After single oral administration of Mancozeb to female ICR mice, the immunopathological parameters (body- and organ-weight, splenic cellularity hematological parameters), mitogen (Con A, PHA+IL-2, LPS)-induced splenocyte proliferation (SP) and splenic IgM plaque forming cell (PFC). WBC and splenic cellularity were decreased, but liver-, kidney-, and spleen-weight were increased when compared with control group. Splenic IgM PFC against SRBC was slightly lowered. Mitogen-induced proliferation of spleen cells from Mancozeb-treated mice was not signifcantly changed ex vivo, however, SP in vitro were significantly lowered in concentration dependent manner. These results indicate that Mancozeb could affect the immune function in mice.

• Elastomers and Composites
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• 제47권2호
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• pp.148-155
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• 2012

EPDM, IIR, and BIIR composites were thermally aged and the crosslink density changes were investigated. Crosslink densities of the EPDM composite increased with increasing the aging time and temperature, whereas those of IIR and BIIR composites for long-term aging at high temperatures tended to decrease. Activation energies for the crosslink density changes of the EPDM composite were higher than those of the BIIR one. The experimental results were explained with the number of allylic hydrogens, activation of the zinc complex, the steric hindrance effect, and oxidation of rubber chain.

• Molecules and Cells
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• 제41권8호
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• pp.717-723
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• 2018

Chimeric antigen receptor (CAR) T-cell therapy, an emerging immunotherapy, has demonstrated promising clinical results in hematological malignancies including B-cell malignancies. However, accessibility to this transformative medicine is highly limited due to the complex process of manufacturing, limited options for target antigens, and insufficient anti-tumor responses against solid tumors. Advances in gene-editing technologies, such as the development of Zinc Finger Nucleases (ZFNs), Transcription Activator-Like Effector Nucleases (TALENs), and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR/Cas9), have provided novel engineering strategies to address these limitations. Development of next-generation CAR-T cells using gene-editing technologies would enhance the therapeutic potential of CAR-T cell treatment for both hematologic and solid tumors. Here we summarize the unmet medical needs of current CAR-T cell therapies and gene-editing strategies to resolve these challenges as well as safety concerns of gene-edited CAR-T therapies.

• Proceedings of the PSK Conference
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.107.2-107.2
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• 2003

Bisphenol A(BPA) is a monomer widely used in the manufacturing polycarbonate plastic or epoxy resin and Mancozeb (MCZ), a polymeric complex of zinc and manganese salts of ethylene bisthiocarbamate, is widely used in agriculture as fungicide, insecticide and herbcide. These chemicals have been recently known as endocrine disruptors. To investigate the effects of BPA and MCZ on LPS-induced cytokine production (TNF-${\alpha}$) in vivo, female ICR mice were administered to various concentration of these materials (BPA; 100, 500, 1000 mg/kg/day, and MCZ; 250, 500, 1000, 1500 mg/kg/day) for 30 days and serum cytokine levels were measured at 1h post LPS injection (day 32) in BPA- or MCZ-administered mice. (omitted)

• Proceedings of the PSK Conference
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.114.1-114.1
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• 2003

Mancozeb is a protective fungicide on plants and a polymeric complex of ethylene bisdithiocarbamate manganese with zinc salt. It is reported to induce teratogenic and carcinogenic effect in laboratory animals. But the immunomodulating effects of Mancozeb exposure have not been systemically evaluated. The purpose of this study was to investigate the effects of Mancozeb on cell-mediated immunity in mice. For ex vivo assessment, mice were orally exposed to Mancozeb dissolved in distilled water as concentrations of 2,500, 5,000, 10,000 mg/kg for single occasion (acute exposure) or 250, 1,000, 1,500 mg/kg/day 5 days a week for 30days(subacute). (omitted)

• Journal of the Korean Chemical Society
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• 제28권2호
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• pp.121-129
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• 1984

The adsorption characteristics of heavy metal ions $(Ni^{2+}$, $Zn^{2+}$) on domestic activated carbon which manufactured from the wood, waste rubber and coal has been studied. The following conclusions were obtained by investigating the effect of pH, halides, cyanide and temperature on the absorption of heavy metal ions and by determining absorption rate and absorption isotherms. When heavy metal ions were adsorbed on activated carbon in the pH range from 6 to 7, treated heavy metal ions were almost come to the equilibrium and recovered in the form of complex anions such as $MX_4^{2- }$and $M(CN)_4^{2-}$ in an hour. The absorption isotherms of heavy matel ions were well fitted in Freundlich's equation. Heavy metal complex anions on activated carbon were easily eluted by using 0.1N HCl solution. These results suggest that the complex anions have unexpectedly strong affinity for the surface of activated carbon.

• Bulletin of the Korean Chemical Society
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• 제30권8호
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• pp.1738-1742
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• 2009

Nanocrystalline Zn$Fe_2O_4$ oxide-semiconductor with spinel structure was synthesized by the polymerized complex (PC) method and investigated for its photocatalytic and photoelectric properties. The observation of a highly pure phase and a lower crystallization temperature in Zn$Fe_2O_4$ made by PC method is in total contrast to that was observed in Zn$Fe_2O_4$ prepared by the conventional solid-state reaction (SSR) method. The band gap of the nanocrystalline Zn$Fe_2O_4$ determined by UV-DRS was 1.90 eV (653 nm). The photocatalytic activity of Zn$Fe_2O_4$ prepared by PC method as investigated by the photo-decomposition of isopropyl alcohol (IPA) under visible light (${\geq}$ 420 nm) was much higher than that of the Zn$Fe_2O_4$ prepared by SSR as well as Ti$O_{2-x}N_x$. High photocatalytic activity of Zn$Fe_2O_4$ prepared by PC method was mainly due to its surface area, crystallinity and the dispersity of platinum metal over Zn$Fe_2O_4$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• 제28권6호
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• pp.351-359
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• 2015

Next-generation displays should be transparent and flexible as well as having high resolution and frame number. The main factor for active matrix organic light emitting diode and next-generation displays is the development of TFTs (thin-film transistors) with high mobility and large area uniformity. The TFTs used for transparent displays are mainly oxide TFT that has oxide semiconductor as channel layer. Zinc-oxide based substances such as indium-gallium-zinc-oxide has attracted attention in the display industry. In this paper, the mobility improvement of low cost oxide TFT is studied for fast operating next-generation displays by overcoming disadvantages of amorphous silicon TFT that has low mobility and poly silicon TFT that requires expensive equipment for complex process and doping process.

• Korean Journal of Materials Research
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• 제10권1호
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• pp.7-14
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• 2000

The object of this study was to improve electrophotographic photoreceptor using metal free-phthalocyanine dye sensitized system. In here a various types of metal free-phthalocyanine and polymers and hydrazone were used as charge generation material(CGM) and binder, respectively, and also the hydrazone derivative or zinc complex was used as charge transport material(CTM). It was found that $x-H_2Pc$ showed the highest sensitivity among the ${\alpha}-$, ${\beta}-$ and x- metal free-phthalocyanine($x-H_2Pc$) as CGM. The photoreceptor made by $x-H_2Pc$ and hydrazone derivative as CGM and CTM, respectively, showed the highest ratio of dark decay having 73.1% and the good sensitivity of $1.50lux{\cdot}sec$ compared to other photoreceptors.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.3052-3058
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• 2014

In this article, we have designed and synthesized a novel donor-${\pi}$-acceptor (D-${\pi}$-A) type porphyrin-based sensitizer (denoted UI-5), in which a carboxyl anchoring group and a 9,9-dimethyl fluorene were introduced at the meso-positions of porphyrin ring via phenylethynyl and ethynyl bridging units, respectively. Long alkoxy chains in ortho-positions of the phenyls were supposed to reduce the degree of dye aggregation, which tends to affect electron injection yield in a photovoltaic cell. The cyclic voltammetry was employed to determine the band gap of UI-5 to be 1.41 eV based on the HOMO and LUMO energy levels, which were estimated by the onset oxidation and reduction potentials. The incident monochromatic photon-to-current conversion efficiency of the UI-5 DSSC assembled with double-layer (20 nm-sized $TiO_2$/400 nm-sized $TiO_2$) film electrodes appeared lower upon overall ranges of the excitation wavelengths, but exhibited a higher value over the NIR ranges (${\lambda}$ = 650-700 nm) compared to the common reference sensitizer N719. The UI-5-sensitized cell yielded a relatively poor device performance with an overall conversion efficiency of 0.74% with a short circuit photocurrent density of $3.05mA/cm^2$, an open circuit voltage of 0.54 mV and a fill factor of 0.44 under the standard global air mass (AM 1.5) solar conditions. However, our report about the synthesis and the photovoltaic characteristics of a porphyrin-based sensitizer in a D-${\pi}$-A structure demonstrated a significant complex relationship between the sensitizer structure and the cell performance.