• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.05a
• /
• pp.51-53
• /
• 2005

$Zn_{1-x}Cd_xO$ thin films were grown on (0001) sapphire substrates by pulsed laser deposition. The energy bandgap of $Zn_{1-x}Cd_xO$ films decreases withincreasing Cd content. An increase of Cd content also leads to the emission broadening and degraded crystallinity. The absorption edge and ultraviolet emission peak shift to lower energy from 3.357 eV to 3.295 eV and 3.338 eV to 3.157 eV, respectively, with increasing Cd content from 0.3% to 3%. The Stokes' shift between the absorption and emission indicates the increase of localization of exciton with Cd content.

• Proceedings of the KIEE Conference
• /
• 2000.07e
• /
• pp.56-59
• /
• 2000

$CdGaInS_4$ and $CdGaInS_4:Er^{3+}$ single crystals crystallized in the rhombohedral(hexagonal) structure. with lattice constants $a=3.913{\AA},\;c=37.245{\AA}$ for $CdGaInS_4$, and $a=3.899{\AA}$ and $c=36.970{\AA}$ for $CdGaInS_4:Er^{3+}$. The optical absorption measured near the fundamental band edge showed that the optical energy band structure of these compounds had a direct and indirect band gap. the direct and indirect energy gaps are found to be 2.771 and 2.503 eV for $CdGaInS_4$, and 2.665 and 2.479 eV for $CdGaInS_4:Er^{3+}$ at 10 K. The temperature dependence of the optical energy gap was well represented by the Varshni equation. In $CdGaInS_4$, the values of ${\alpha},\;{\beta}$ of the direct and the indirect energy gap were found to be $7.57{\times}10^{-4}eV/K$. $6.53{\times}10^{-4}eV/K$ and 240K. 197K. and the values of ${\alpha}$ and ${\beta}$ of the direct and the indirect energy gap in the $CdGaInS_4:Er^{3+}$ were given by $8.28{\times}10^{-4}eV/K,\;2.08{\times}10^{-4}eV/K$ and 425 K, 283 K, respectively.

• BMB Reports
• /
• v.33 no.6
• /
• pp.454-462
• /
• 2000

Interleukin-4(IL-4) is known to be a major cytokine regulating immunoglobulin E(IgE) response by the induction of IgE production and type II IgE receptor(IgER II: CD23) expression. Recently, however, the role of neuroendocrine factors has been implicated in modulating the IgE response. Among various neuroendocrine growth factors, we investigated the effects of the insulin-like growth factor-1(IGF-1) since IL-4 and IGF-1 share common intracellular signaling molecules, such as the insulin receptor substrate-1/2(IRS-1/2) to induce a specific cellular response. In the human peripheral blood mononuclear cell (PBMC) cultures, IGF-1 was capable of inducing a substantial level of IgE production in a dose-dependent manner. It also noticeably upregulated the IL-4-induced or IL-4 plus anti-CD40-induced IgE production. Similarly, the IGF-1-induced IgE production was enhanced by IL-4 or anti-CD40 in an additive manner, which became saturated at high concentrations of IGF-1. Although IGF-1 alone did not induce IgER II (CD23) expression, it augmented the IL-4-induced surface CD23 expression in a manner similar to the action of anti-CD40. These results imply that IGF-1 is likely to utilize common signaling pathways with IL-4 and anti-CD40 to induce IgE and IgER II expression. In support of this notion, we observed that IGF-1 enhanced the IL-4-induced signal transducers and activators of transcription 6(STAT6) activation and independently induced $NF-{\kappa}B$ activation. Both of these bind to the IgE(C) or IgER II (CD23) promoters. Together, our data suggest that IL-4 and IGF-1 work cooperatively to activate STAT6 and $NF-{\kappa}B$. This leads to the subsequent binding of these transcription factors to the $C{\varepsilon}$ and CD23 promoters to enhance the expression of IgE and IgER II. The observed differential ability of IGF-1 on the induction of IgE vs. IgER II is discussed based on the different structure of the two promoters.

• Journal of Nutrition and Health
• /
• v.26 no.3
• /
• pp.286-298
• /
• 1993

In order to investigate the effect of selenium (Se) on the liver damage, metallothionein synthesis and hepatic antioxidative detoxification system in cadmium(Cd) administered rats. Sprague-Dawley male rats(60\\5g) were divided into two diet groups, depending on with (CdS groups) or without (Cd groups) 0.5ppm Se supplementation and fed experimental diets ad libidum for 4 weeks. And then each group was again subdivided into five groups, depending on injection number of Cd, i.e., 0, 1, 2, 3, and 4 times of 2.5mg Cd/kg of body wt once a day. Hemoglobin concentration, hematocrit values, superoxide dismutase, glutathione peroxidase and glutathione S-transferase activite were decreased progressively with increasing number of Cd injection, but increased by the supplementation of Se. The reduced form of glutathione (GSH) contents in blood and liver and vitamin E content were decreased and oxidized form (GSSG) increased in Cd groups, but these of Se supplemented groups were not very different from controls. Cd reduced liver vitamin E content which was not restored by Se supplementation. Liver lipid peroxide values were elevated with increasing doses of Cd, but Se supplementation reduced these elevated levels. Accumulation of metallothionein in liver and kidney was increased with increasing number of Cd injection, but Se did not affect on them. Histological examination revealed that lysosomes were significantly increased and mitochondria and Golgi apparatus were enlarged by Cd, however, these changes were reduced by Se. It was concluded that Se administration promoted antioxidative detoxification and alleviated peroxidative damage in rat liver by Cd.

• The Journal of Korean Medicine
• /
• v.25 no.2
• /
• pp.51-66
• /
• 2004

Objectives : To evaluate experimentally the clinical effect of Bojeongjeongcheon-tang, we observed the cytokines ($IL-1{\beta}$/TEX>, IL-4, IL-5, IL-6, IL-10, TNF-{\alpha},{\;}TGF-{\beta},{\;}IFN-{\gamma}$) and what effect they have on IgE in B cells of a rat. Methods : First of all, we extracted the spleens of healthy Balb/c mice and separated B cells from them. These B cells were cultured with anti-CD40 mAb (500 ng/ml), rmIL-4 (500 U/ml), Bojeongjeongcheon-tang (100 ug/ml, 10 ug/ml, 1 ug/ml). We used rmiL-10 (50 ng/ml) as a control group. Furthermore, we analyzed the expression of IgE, CD23, CD69 and the coherence of HRF in B cells using a flow cytometer. We also analyzed the cytokine gene expression in B cells by reverse transcriptase-PCR. We also measured B cells proliferation using the Liquid Scintillation Counter. Results : In this study, the Bojeongjeongcheon-tang treated group showed a tendency to decrease depending on the density compared with the control group in the expression of IgE+, CD23+, CD69, HRF. All of the Bojeongjeongcheon-tang treated group showed inhibitory effects with $IL-1{\beta}$, IL-4, IL-5 and proliferating effects with IL-6, IL-10, and $IFN-{\gamma}$ on cytokines transcript expression depending on the density. Meanwhile, $TNF-{\alpha}$ increased in all density. In IgE production, there was inhibitory effect on Bojeongjeongcheon-tang (both 100 ug/ml and 10 ug/ml) of significance (p < 0.01, p < 0.05). Also in B cell proliferation, the result revealed an inhibitory effect of Bojeongjeongcheon-tang (both 100 ug/ml and 10 ug/ml), of significance (p < 0.001, p < 0.01). Conclusions : This study shows that Bojeongjeongcheon-tang has an inhibitory effect on the production and activity of B cells. Also it inhibited CD23, IL-4 activity and IgE production and activation. It is obvious that Bojeongjeongcheon-tang treats asthma by inhibiting the production of histamine and HRF, IL-5 and proliferating IL-10. Also Bojeongjeongcheon-tang has some preventive effects on bronchial change by inhibiting $TGF-{\beta}$, which stimulates the bronchial transformation.

• Nuclear Engineering and Technology
• /
• v.51 no.3
• /
• pp.731-737
• /
• 2019

In this study, a new measurement method based on voltage transients in CdZnTe detectors response to low energy photon irradiations is applied to measure the electron mobility (${\mu}_e$) and electron mobility-lifetime product $({\mu}{\tau})_e$ in a CdZnTe detector. In the proposed method, the pulse rise times are derived from low energy photon response to 59.5 keV($^{241}Am$), 88 keV($^{109}Cd$) and 122 keV($^{57}Co$) ${\gamma}-rays$ for the irradiation of the cathode surface at each detector for different bias voltages. The electron $({\mu}{\tau})_e$ product was then determined by measuring the variation in the photopeak amplitude as a function of bias voltage at a given photon energy using a pulse-height analyzer. The $({\mu}{\tau})_e$ values were found to be $(9.6{\pm}1.4){\times}10^{-3}cm^2V^{-1}$ for $1000mm^3$, $(8.4{\pm}1.6){\times}10^{-3}cm^2V^{-1}$ for $1687.5mm^3$ and $(7.6{\pm}1.1){\times}10^{-3}cm^2V^{-1}$ for $2250mm^3$ CdZnTe detectors. Those results were then compared with the literature $({\mu}{\tau})_e$ values for CdZnTe detectors. The present results indicate that, the electron mobility ${\mu}_e$ and electron $({\mu}{\tau})_e$ values in CdZnTe detectors can be measured easily by applying voltage transients response to low energy photons, utilizing a fast signal acquisition and data reduction and evaluation.

• Journal of the Korean Chemical Society
• /
• v.30 no.1
• /
• pp.51-56
• /
• 1986

Polarographic behavior of cadmium(II) and copper (II) complexes of 1,5-diphenylcarbohydrazide in dimethylsulfoxide have been investigated by the DC polarography. The reduction processes are estimated as follows; Cd(II)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.12V)}$${\to}$Cd(I)${\cdot}$DPH Complex. Cd(I)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.74V)}$${\to}$Cd(Hg) + nDPH. Cu(II)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.44V)}$${\to}$Cu(I)${\cdot}$DPH Complex. Cu(I)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.84V)}$${\to}$Cu(Hg) + nDPH. The limiting currents of all reduction wave are irreversible. The number of ligand and the dissociation constant for Cu(I)${\cdot}$1.5-diphenylcarbohydrazide complex were found to be 2 and 5.12 ${\times}10^{-8}$, respectively. All reduction waves of complexes are irreversible. Based on the experimental results, the polarographic reductions of complexes in dimethylsulfoxide solution occurred in two one-electron steps.

• The Journal of Pediatrics of Korean Medicine
• /
• v.25 no.1
• /
• pp.1-27
• /
• 2011

Objectives: The purpose of this study is to investigate the effects of Yijungtang(YJT) on atopic dermatitis in an in-vitro and in-vivo experiment using a RBL-2H3 mast cells and a NC/Nga atopic dermatitis mouse. Methods: In-vitro experiment, IL-4, IL-13 mRNA expression were evaluated by a real-time PCR, IL-4, IL-13 production by ELISA and transcription factor as GATA-1, GATA-2, NF-AT1, NF-AT2, AP-1 and NF-kB by western blotting. In-vivo experiment, clinical skin score we evaluated by, hematology and Serum total IgE and IgG1 of NC/Nga atopic dermatitis mouse, cytokine level, total number of cell, Immunohistochemical staining and Histological features of auxiliary lymph node(ALN), draining lymph node(DLN), peripheral blood mononuclear cells(PBMCs) and dorsal skin tissue in NC/Nga mouse. Results: YJT decreased IL-4, IL-13 mRNA expression, IL-4, IL-13 production and prominently decreased the expression of mast cell specific transcription factors including GATA-2, NF-AT2, c-Fos and NF-kB. YJT oral administration reduced the levels of skin severity scores. It also decreased the level of inflammatory cytokines such as IL-5, IL-13, histamine and IgE in the serum. It elevated IFN-gamma level in the spleenocyte culture supernatant but decreased. $CD3e^+$, $CD19^+$, $CD4^+$, $CD8^+$, $CD3e^+CD69^+$, $CD11b^+Gr-1^+$, $CCR3^+$ in the PBMCs, $CD4^+$, $CD8^+$, $CD3e^+CD69^+$, $B220^+CD23^+$ in the ALN, $CD4^+$, $CD3e^+CD69^+$ in the ALN and $CD4^+$, $CD11b^+Gr-1^+$ in the dorsal skin. Histological examination showed that infiltration levels of immune cells in the skin of AD-induced NC/Nga mice were much improved by YJT oral administration. Conclusions: The anti-allergic activities of YJT may be mediated by down-regulation of Th2 cytokines, such as IL-4 and IL-13, through the regulation GATA-2, NF-AT2 and NF-kB transcription factors in mast cells. YJT would be regulate molecular mediators and immune cells which are functionally associated with atopic dermatitis induced in NC/Nga mice, and may play an important role in recovering AD symptoms.

• BMB Reports
• /
• v.30 no.6
• /
• pp.431-437
• /
• 1997

Since the role of CD40 on the interleukin-4(IL-4) -induced B cell activation has been strongly implicated in the agumentation of IgE production and response, we have investigated the intracelluar signaling pathways utilized by IL-4 and CD40 for type II IgE receptor (CD23) expression. IL-4 and anti-CD40 antibody treatment of human B cells, independently caused a rapid induction of CD23 gene activation within 2 h. There was a noticeable synergism between the action of the two agents inducing CD23 expression: the addition of anti-CD40 to the IL-4-treated culture significantly agumented the IL-4-induced CD23 on both mRNA and surface protein levels, and the inclusion of IL-4 in the anti-CD40-treated cells caused a further increase of CD23 expression far above the maximal level induced by anti-CD40. Protein tyrosine kinase (PTK) inhibitors effectively suppressed the both IL-4- and anti -CD40-induced CD23 expression. whereas protein kinase C (PKC) inhibitors had no effects. Electrophoretic mobility shift assays (EMSA) have shown that IL-4 and anti-CD40 induce the activation of NF-IL-4 and $NF-_{K}B$, respectively, binding to the CD23 promoter, both in a PKC-independent and PTK-dependent manner. These data suggest that the synergistic activation of CD23 gene expression by IL-4 and anti-CD40 is mediated by co-operative action of distinct nuclear factors. each of which is rapidly activated via PKC-independent and PTK-dependent process.

• Electrical & Electronic Materials
• /
• v.8 no.5
• /
• pp.619-625
• /
• 1995

Polycrystalline CdTe thin film has been studied for photovoltaic application due to the 1.45 eV band gap energy ideal for solar energy conversion and high absorption coefficient. The formation of low resistance contact to p-CdTe is difficult because of large work function(>5.5eV). Common methods for ohmic contact to p-CdTe are to form a p+ region under the contact by in-diffusion of contact material to reduce the barrier height and modify a p-CdTe surface layer using chemical treatment. In this study, the surface chemical treatment of p CdTe was carried out by H$\_$3/PO$\_$4/+HNO$\_$3/ or K$\_$2/Cr$\_$2/O$\_$7/+H$\_$2/SO$\_$4/ solution to provide a Te-rich surface. And various thin film contact materials such as Cu, Au, and Cu/Au were deposited by E-beam evaporation to form ohmic contact to p-CdTe. After the metallization, post annealing was performed by oven heat treatment at 150.deg. C or by RTA(Rapid Thermal Annealing) at 250-350.deg. C. Surface chemical treatments of p-CdTe thin film improved metal/p-CdTe interface properties and post heat treatment resulted in low contact resistivity to p-CdTe.Of the various contact metal, Cu/Au and Cu show low contact resistance after oven and RTA post-heat treatments, respectively.